Rozprawy doktorskie: „IR HEATER”

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Choi, Sung In. "Smart Localized Heating Control System With Human Movement Tracking". Master's thesis, Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/407171.

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Electrical Engineering
M.S.E.E.
According to the U.S. energy consumption survey in 2012, about 25% of the commercial and 42% of the residential building energy were used for heating. Despite the development of new and more efficient Heating, Ventilation, and Air Conditioning (HVAC) systems over the years, the high energy consumption in heating is still one of the major energy efficiency issues. Studies showed that decreasing HVAC operating temperature set points by 4°F will result in energy savings of 15% or more. Thus, the smart localized heating control (SLHC) system was designed and prototyped to provide localized heat directly to a person so that HVAC can run at a lower temperature set point. SLHC detects human movement and delivers the heat based on the result of the target location estimation and temperature measurement feedback. To detect the human movement, image processing techniques were used; image segmentation, mass center detection, background subtraction using the Mixture of Gaussian model, and human feature detection. In SLHC, a near-infrared heater and a tracking function were used to provide an instant and a direct heat to the person in order to minimize wasting energy. The SLHC system is divided into the sensing and processing (SP) and the heating and regulating (HR) subsystem. The SP’s primary function is to process captured video images and measured temperature data. SP also generates and sends the heater operating signal to HR. HR purposes to control the heater’s direction and power based on the signal. The communication between SP and HR was established through Wi-Fi enabled development platform. The SLHC prototype successfully processed the sensing data and transmitted the control signal. The result shows that it detected human movement and estimated the person’s location in 3D space within 10% margin of error. Also, it delivered the focused heat to the surface of the human body and increased the temperature by 10.0°F in 3 minutes at the distance of 1.5m away from the heater. This cost-effective, wireless, and localized heating system demonstrates the potential to improve energy efficiency in buildings.
Temple University--Theses

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Bendžius, Simonas. "Dangus ir pragaras: Bažnyčios mokymas ir jaunimo subkultūros vaizdiniai". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140721_113201-51687.

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Šiame magistro darbe pateikiamos Romos Katalikų Bažnyčios ir jaunimo subkultūros sampratos apie krikščioniškojo dangaus ir pragaro dogmas. Šiam tikslui nagrinėjama oficialioji Bažnyčios pozicija (dokumentai, popiežių raštai ir kt.) bei šiandienos teologinės hipotezės; tuo metu praktinėje darbo dalyje pateikiami jaunimo (14-25 m.) apklausos apie dangų ir pragarą rezultatai. Atkreipiamas dėmesys, kad krikščioniškojo dangaus ir pragaro sampratos mažai pažįstamos ir suprantamos tiek tarp pačių tikinčiųjų, tiek ir tarp žmonių, kurie nėra Bažnyčios nariai. Šios dogmos suvokiamos perdėm supaprastintai ir neretai - sukarikatūrintai, o tam daugiausia įtakos daro masinės komunikacijos priemonės, meniniai filmai ir knygos. Todėl šiame magistro darbe siūlomas "aktyviojo" dangaus modelis - teologinė hipotezė, teigianti apie pojūčių, gyvenimiškosios patirties, meilės, meno ir kitų jaunimui aktualių dalykų svarbą, mąstant apie krikščioniškąją amžinybės perspektyvą. Manome, kad Bažnyčia, akcentuodama "aktyvųjį" dangų, gerokai sumažintų atotrūkį tarp teologijos ir jauno žmogaus, be to, toks kalbėjimas duotų naudos pačių Bažnyčios narių tikėjimo gilinimui.
This thesis presents Christian concepts of Heaven and Hell dogmas perceived by the Roman Catholic Church and the youth subculture. For this purpose it presents the official position of the Church (documents, papal writings, etc..) and today's theological hypothesis; In the practical part of the work it presents the the youth (14-25 years) survey‘s result about Heaven and Hell. Attention is drawn to the context that Christian concepts of Heaven and Hell are too little understood among the believers and between people who are not members of the Church. These perceived overly simplistic dogma and often - a parody, and this is mostly influenced by means of mass communication, movies and books. Therefore, this thesis propose the "active" Heaven model. This is a theological hypothesis, which emphasizes feelings, real-life experience, love, art and other subjects relevant to young people. This is important to reflect on the Christian perspective of eternity. We believe that the Church, emphasizing the „active“ Heaven model "active" could significantly reduce the gap between the theological claims and the young man, in addition to such talk would benefit the faith of the most members of the Church.

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Martin, James 1960. "Between Heaven and Mirth:". The Church in the 21st Century Center at Boston College, 2011. http://hdl.handle.net/2345/bc-ir:103730.

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Jonutytė, Inga. "Jūrininkų psichologinių ir socialinių darbo sąlygų ir sveikatos sutrikimų sąsajos". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070803.095813-28912.

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Darbo tikslas: įvertinti psichologinių ir socialinių darbo sąlygų ir jūrininkų fizines ir psichologine sveikatos sutrikimu sąsajas . Tyrimo metodai: duomenys buvo surinkti vienmomentinės anketinės apklausos būdu, ištyrus 370 Klaipėdos jūrininkų ligoninėje dėl privalomojo sveikatos patikrinimo besikreipiančius jūrininkus. Anoniminės anketinės apklausos būdu, naudojantis norvegų pasiūlytu Negatyvaus elgesio darbe klausimynu, buvo surinkta informacija apie jūrininkų patiriamo negatyvaus elgesio darbe formas, trukmę. Tiriamieji informavos apie diagnozuotus sveikatos sutrikimus. Tirta jūrininkų vidinė darna, potrauminio streso sutrikimo simptomai, minimalūs psichikos sveikatos sutrikimai. Tyrimo duomenys buvo analizuojami statistiškai, taikant SPSS 13,0 for Windows programą. Apskaičiuotas Spirmano koreliacijos koeficientas tikslu įvertinti jūrininkų patiriamo psichologinio teroro darbe sąsajas su gydytojo diagnozuotais fizinės sveikatos sutrikimais bei psichologinės sveikatos rodmenimis. Rezultatai: bent vieną negatyvaus elgesio aktą per 6 mėnesius patyrė 75 proc. jūrininkų savo darbe, 25 proc. jūrininkų nepatyrė nė vieno negatyvaus elgesio akto. Dažno psichologinio teroro jūrininkų darbe paplitimas siekė 3,8 proc., atsitiktinio – 10,1 proc. 2,3 proc. jūrininkų nurodė, kad labai jaučia stresą darbe. Stebėtos statistiškai reikšmingos sąsajos tarp jūrininkų patiriamo psichologinio teroro darbe ir arterinės hipertenzijos (r =0,154), kaklo/peties skausmų (r =0,138), migrenos (r =0,15... [toliau žr. visą tekstą]
Aims of the study–to evaluate the associations between psychological terror in the workplace and adverse health outcomes. Methods. totally 370 seafarers, attending the mandatory health examination in the Marine health care centre. The Lithuanian version of the Norwegian Negative Acts Questionnaire was used for the investigation of the prevalence and duration of negative acts among seafarers. The investigated seafarers were asked about diagnosed by the physician health outcomes over the last twelve months. The questionnaires on the sense of coherence, post-traumatic stress disorder and minor psychological disorders (psychological distress) were distributed as well. The statistical software SPSS 13.0 for Windows was used in the statistical analysis. The associations between psychological terror in the workplace and adverse health outcomes were evaluated by Spirman’s correlation coefficient. Results. 75.0% of the investigated seafarers were exposed to at least one negative act over the last six months, only 25.0% were not exposed. The prevealence of severe bullying was 3.8%, the prevalence of occasional bullying was 10.1%. 2.3% of the investigated seafarers perceived severe stress in the workplace. Statistically significant associations between psychological terror and arterial hypertension (r=0.154), neck/shoulder pain (r=0.138), migraine (r=0.158), diseases, prostate diseases (r=0.122), hand/arm pain (r=0.196), non allergic skin diseases (r=0.138) were observed... [to full text]

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Wolf, Jacob Charles Joseph. "Harmonizing Heaven and Earth: Democratization and Individualism in American Religion". Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:108949.

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Thesis advisor: R. Shep Melnick
Many political thinkers have suggested that religion is a necessary prerequisite for the proper functioning of American democracy. Foremost among them is Alexis de Tocqueville who argues, in particular, that religion serves as a counterbalance to individualism and crass acquisitiveness—two of the most worrisome aspects of American democracy. Yet, Tocqueville’s own analysis bids us to ask whether religion still serves this beneficial purpose nearly 200 years later, or whether democratization and individualism have not remade religion itself. The primary theme of the dissertation is therefore to investigate whether democratization and individualism have wrought changes of real significance in American religion and religious institutions. In the first part, I argue against the secularization thesis on the grounds that contemporary developments in American religion, such as the so-called rise of the “nones” and the growing distrust of organized religion, are explicable not by secularization but by democratization and individualism. To understand this phenomenon better, I return to the French liberal tradition of Benjamin Constant and Alexis de Tocqueville to articulate a theory of democratic deformalization—a process whereby American democracy breaks down the “formal” elements of religion. In the second part, I argue that individualism has caused a host of quantitative changes in American religion, including declining church membership, dwindling church participation, and a collapse in the perceived importance of organized religion itself. There are notable qualitative changes as well, including increasingly tenuous connections to churches, a proliferation of religious options within churches, and a new megachurch model that is better able to cater to individual taste and preference. In the third and most substantial part, I take up the question of whether individualism itself has changed or evolved over time, in predictable or unpredictable ways. Here, I argue that there has been a general shift from utilitarian individualism towards expressive individualism, with profound consequences for religious institutions and for society itself. The former, with its connection to the Protestant work ethic and Puritan social philosophy tends to cause an inclination in individuals to partake in community, submit to institutions, and follow moral and religious rules; the latter, with its belief in authenticity, causes a profound disdain for communal sources of authority, social institutions, and moral constraints. I conclude by arguing that the anthropology of expressive individualism, and its historical growth since the 1960s, proves to be the fundamental cause behind all these changes
Thesis (PhD) — Boston College, 2020
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Political Science

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Tamošaitis, Donatas. "Geoterminio šildymo ekonominis ir techninis įvertinimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110224_091359-85043.

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Žemės šilumos siurblių sistemos surenka žemės šilumą, dažniausiai vertikaliu U formos gręžinio šilumokaičiu. U formos gręžinio šilumokaičio našumas priklauso nuo šiluminių žemės savybių, taip pat nuo gręžinyje naudojamo skiedinio ar užpildo. Siekiant, kad Žemės šilumos siurblių sistemos pasiteisintų, projektuojant reikia atsižvelgti į geologinių struktūrų šiluminį laidumą ir gręžinio šilumokaičio šiluminę varžą. Šio darbo tikslas buvo nustatyti šilumos siurblio, naudojančio grunto šilumą, pritaikymo individualioje sodyboje siurblio techninis ir ekonominis įvertinimas. Nustatyta, kad investicijos projektui įgyvendinti, kai gyvenamajam pastatui šildyti ir buitiniam karštam vandeniui ruošti šildymo sezono metu šilumą gamina šilumos siurblys, naudojantis grunto šilumą, palyginti su tiesioginiu elektros naudojimu pastatui šildyti ir buitiniam karštam vandeniui ruošti, atsiperka per 6,3 metus. Šiluminės reakcijos testas padeda nustatyti šiluminį žemės laidumą (λ) gręžinio šilumokaičio įrengimo vietoje, bei efektyvią gręžinio šilumokaičio šiluminę varžą (Rb). Pagrindinis tikslas buvo suderinti gręžinio šilumokaitį su žemės sąlygomis, taip pat nustatyti gręžinio gylio poveikį (60 m: VB2; 90 m: VB3).
Ground source heat pump systems exchange heat with the ground, often through a vertical, U-tube, borehole heat exchanger. The performance of this U-tube borehole heat exchanger depends on the thermal properties of the ground formation, as well as grout or backfill in the borehole. The design and economic probability of ground source heat pump systems need the thermal conductivity of geological structure and thermal resistance of borehole heat exchanger. An economic and technical evaluation of the heat pump, which is using ground heat, in individual homestead. It was found that the investment for this project, when heat pump using ground heat is used to heat residential building and domestic hot water in heating season, compared with the use of direct electric heating of buildings and domestic hot water payback within 6.3 years. Thermal response test method allows the in-situ determination of the thermal conductivity (l) of the ground formation in the vicinity of a borehole heat exchanger, as well as the effective thermal resistance (Rb) of this latter. The main goal has been to determine same in-situ ground type of borehole heat exchanger, including the effect of borehole’s depths (60 m: VB2; 90 m: VB3).

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Liaudanskaitė, Neringa. "65 metų ir vyresnių Vilniaus gyventojų gyvensena ir subjektyvus sveikatos vertinimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2012~D_20140627_185234-92989.

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Visuomenės senėjimas rodo gerėjančias gyvenimo sąlygas, sveikatos priežiūros kokybės gerėjimą, tačiau visuomenės senėjimas turi ir neigiamų pasekmių. Visuomenei senstant daugėja lėtinių ligų, specifinių, seniems žmonėms būdingų būklių, todėl didėja poreikis pagyvenusių žmonių socialinei ir medicininei priežiūrai, atsiranda naujų ekonominių iššūkių šaliai. Pakeisti ar sureguliuoti gyventojų senėjimo procesus ir jų padarinius yra sunku, tačiau žinant sveikatą įtakojančius veiksnius ir jų padarinius galima geriau pasirengti šių problemų sprendimui. Tyrimo tikslas: įvertinti 65 m. ir vyresnių Vilniaus gyventojų gyvenseną ir subjektyvų sveikatos vertinimą Uždaviniai: 1. Nustatyti 65 m. ir vyresnių žmonių gyvensenos veiksnių (rūkymo, alkoholio vartojimo, mitybos ir fizinio aktyvumo) paplitimą. 2. Įvertinti 65 m. ir vyresnių žmonių sveikatos būklę 3. Nustatyti 65 m. ir vyresnių žmonių subjektyvų savo sveikatos būklės vertinimą. 4. Įvertinti 65 m. ir vyresnių žmonių subjektyvios sveikatos būklės sąsajas su gyvensenos veiksnių paplitimu. 5.Įvertinti 65 m. ir vyresnių žmonių gyvensenos sąsajas su bendra fizine sveikata. Metodika. Darbo uždaviniams įgyvendinti ir tikslui pasiekti buvo panaudotas interviu apklausos metodas, naudojant šiam tyrimui sukurtas anketas (1 priedas). Anketos buvo anonimiškos. Apklausa vykdyta Antavilių pensionate, Vilniaus Gerontologijos ir reabilitacijos centre bei Vilniaus pirminėse sveikatos priežiūros įstaigose. Į tyrimą buvo įtraukti asmenys 65 metų amžiaus... [toliau žr. visą tekstą]
Aging of the public population shows the improvement in living conditions and health care quality, still this process has its negative consequences as well. Because of aging, both the chronic diseases and specific conditions for the elderly are increasing, thus making bigger demands of older people for social and medical care and creating new economic challenges for the country. It is very difficult to replace or adjust the aging processes and their effects; however, if we take into account the factors that have an impact on health and their consequences the better preparation to solve these problems can be done. The aim of the research: to assess the residents of Vilnius city at the age of 65 and older living and their own subjective heath assessment. Objectives : 1. To define the living factors ( smoking, alcohol consumption, nutrition and physical activity) distribution of the people at the age of 65 and older. 2. To assess the people’s health condition at the age of 65 and older. 3. To ascertain people's at the age of 65 and older subjective assessment of their own health. 4. To ascertain people's at the age of 65 and older subjective health condition links with the living factors distribution. 5. To ascertain people's at the age of 65 and older subjective health condition links with their common physical health. Methodology. In order to achieve the objectives and the aim of the study the interview method have been carried out, using the questionnaires developed for this... [to full text]

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Polcyn, Adam D. (Adam Daniel) 1970. "Specific heat of Sr₃CuPt₀₅Ir₀.₅O₆ below 1K". Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85335.

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Gataveckas, Kipras. "Integruotas grunto ir mažaenergio pastato atliekinės šilumos panaudojimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140610_141426-25126.

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Baigiamajame magistro darbe nagrinėjamos grunto ir atliekinės pastato šilumos panaudojimo galimybės mažaenergiame pastate, Vilniaus mieste, Lietuvoje. Suskaičiuoti keturi pastato energijos balansų variantai, naudojant ”CASAnova” kompiuterinę skaičiavimo programą, su skirtingais atitvarų šilumos perdavimo koeficientais. Pastate taikomos dvi energijos taupymo priemonės. Pirmoji yra gruntinis šilumokaitis naudojamas šviežio oro pirminiam pašildymui mechaninio vėdinimo sistemoje, kurio skaičiavimai atliekami ”GAEA” programa. Antroji yra nuotekų šilumos atgavimo šilumokaitis, naudojamas į pastatą tiekiamo šalto vandens pirminiam pašildymui, atgaunant dalį šilumos iš duše susidariusių nuotekų. Pastatui reikiamas metinis šilumos ir vėsos energijos kiekis gaminamas šilumos siurbliu su vertikaliu gręžiniu grunte, kurio skaičiavimams naudojama ”EED” programa. Gręžinių gyliai yra suskaičiuoti kiekvienam pastato energijos balansų variantui. Atlikti ekonominiai skaičiavimai rodo gruntinio ir nuotekų šilumos atgavimo šilumokaičių įdiegimo pastate ekonominę naudą. Pateikti rezultatai rodo kiekvieno varianto energijos poreikius ir gręžinio grunte gylį priklausomai nuo pastato varianto atitvarų šiluminių savybių bei taikomų energijos taupymo sprendimų. Darbą sudaro 9 dalys: įvadas, 6 skyriai, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis – 64 psl. teksto, 41 paveikslai, 14 lentelės, 31 bibliografinis šaltinis.
The final master thesis presents technical analysis of low-energy residential building in Vilnius, Lithuania. Building has low temperature floor heating, mechanical ventilation with heat recovery unit and hot water preparation with buffer tank systems. Using “CASAnova” software is calculated fourth energy balances of building according fourth different heat transfer coefficients of the walls. All heating and cooling energy demand of a building is generated from the ground. It is made by using a heat pump with single borehole. A calculation of borehole sizing is made with “EED” software. Two energy saving technologies are analysed for a building. The first idea is to reduce heat energy consumption of hot water preparation. There is calculated benefit of waste water heat recovery heat exchanger which function is to pre-heat hot water using waste water from the shower. Second idea is to reduce heat energy consumption for fresh air heating in air handling unit. There is calculated benefit of earth-to-air heat exchanger using “GAEA” software. Final result of all calculations shows influence of heat transfer coefficient and energy saving technologies to building annual energy balance and depth of borehole. Economic benefit of using energy saving technologies is calculated. Structure: introduction, 6 chapters, conclusions and suggestions, references. Thesis consists of 64 p. of text, 41 figures, 14 tables and 31 bibliographical entries.

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Kovzan, Daiva. "Kurčiųjų ir neprigirdinčiųjų savarankiškumo ugdymas technologijų pamokose". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060605_174559-74926.

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Each live organism is made to adapt to the constantly changing environment. The success of child’s integration into society, his conduct in society depends on the family and school. Frequently, excessive care by their parents prevents a disabled child from developing independency skills. One of the most important tasks for the school is to prepare an individual for independent life and seek his integration into society. The issue of developing independency of a disabled individual has not been studied in detailed yet. The object of this study is independency of the pupils with hearing impairments. The paper contains an analysis of the reference sources and findings of the study, which disclose the peculiarities of developing independency of the deaf and hard of hearing pupils during technology classes. The respondents were surveyed by test-interview methods and the data obtained were processed with the help of SPSS software. When summarizing the academic, professional and methodical literature, a model of the pupils’ independency was drafted by dividing independency into three groups of its manifestation (inquisitiveness, initiative and organization skills) and by defining technological skills by three types of skills ( planning, information collection and use, technology activities). Analysis of individual programs revealed that the teachers of technologies devote attention to the development of the pupils’ independency at the schools for deaf and heard to hear students... [to full text]

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Smith, Bruce W. "Optically transparent IR reflective heat mirror films of ZNS-AG-ZNS /". Online version of thesis, 1989. http://hdl.handle.net/1850/11360.

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Beniušis, Mantas. "Kelto „Victoria Seaways“ šilumokaičio ir aušinimo vamzdyno virpesių tyrimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140616_155131-41138.

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M. Beniušis „Kelto „Victoria Seaways“ šilumokaičio ir aušinimo vamzdyno virpesių tyrimas“. Laivų projektavimo ir statybos magistratūros studijų programos baigiamasis darbas. Darbo vadovas dr. P. Mažeika, Klaipėdos universitetas: Klaipėda, 2014. Raktažodžiai: virpesiai, laivas, keltas, virpesių tyrimai, šilumokaitis. Baigiamojo darbo teorinėje dalyje aprašoma virpesių klasifikacija, pagrindiniai virpesių žadintojai ir analizuojami įvairūs virpesių lygio mažinimo laive, virpesių skaičiavimo būdai. Eksperimentinėje dalyje pateikiama keltų „Victoria Seaways“ ir „Athena Seaways“ aušinimo sistemos dalies virpesių matavimo metodika. Nagrinėjami reiso Klaipėda-Kylis-Klaipėda metu atliktų matavimų rezultatai, bei nustatomos tiriamos aušinimo sistemos dalies padidintų virpesių lygio priežastys. Paskutinėje darbo dalyje pateikiamos išvados ir rekomendacijos.
M. Beniušis “Vibration research of heat exchanger and cooling piping in Victoria Seaways ferry”. Final work of the master studies of ship design and building program. Academic supervisor Dr. P. Mažeika, Klaipeda University: Klaipėda, 2014. Keywords: vibrations, ship, ferry, vibration research, heat exchanger. The theoretical part of the final work describes the classification of vibration, main excitations of vibration and analyses various methods for reduction of the vibration level on board and vibration calculation. The experimental part presents the vibration measurement methodology in the cooling systems of Victoria Seaways and Athena Seaways ferries. It examines the results of measurements carried out during Klaipėda-Kiel-Klaipėda trip and identifies the reasons for the recent level of vibration in the analysed cooling system. The final part of the work contains the conclusions and recommendations.

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Fraatz, Charles Thomas. "Blessed Is the One Who Reads and Those Who Hear the Words of Prophecy: Rome and Revelation’s Use of Scripture". Thesis, Boston College, 2017. http://hdl.handle.net/2345/bc-ir:107708.

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Thesis advisor: Pheme Perkins
The recognition of Rome in the ciphered images of Revelation 13 and 17–18 is a hallmark of historical criticism on the Revelation to John (John’s Apocalypse). This dissertation examines Revelation’s use of scripture to characterize the Roman Empire like the nations God has already defeated. The prophet-seer John spurred his audience, the churches of Asia Minor, to abandon pagan practices of eating meat sacrificed to idols and participation in emperor worship, practices seemingly tolerated by John’s opponents, Jezebel and the Nicolaitans. Unlike the majority of contemporary Jewish and Christian apocalypses, Revelation uses neither ex eventu prophecy nor pseudepigraphic narration to authorize its message to “come out” of Rome. Instead, Revelation alludes to scripture hundreds, if not a thousand, times. When describing Rome in Revelation 13 and 17–18, John alludes some six dozen times to the defeated Seleucid king Antiochus IV Epiphanes, the nations of Babylon, Tyre, Nineveh, and Edom, and the justly punished Judah and Samaria. God showed his servants the prophets the downfall of these powers, and they all fell. Likewise, he has shown John the vision of Rome’s desolation and the things which will happen to it soon
Thesis (PhD) — Boston College, 2017
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Theology

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Šimkutė, Ingrida, i Gabrielė Lukštaitė. "Daugiabučių namų šilumos kainų kitimo priežastys ir jų mažinimo galimybės Šiaulių mieste". Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140716_083710-32553.

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Baigiamajame bakalauro darbe nagrinėjamos Šiaulių miesto daugiabučių namų šilumos kainų kitimo priežastys ir galimi būdai kaip jas sumažinti. Šilumos tiekimas yra viešąjį interesą atitinkanti paslauga, kuria naudojasi daugelis miesto gyventojų. Kylančios centralizuotai tiekiamos šilumos sektoriaus paslaugų kainos kelia nepasitenkinimą tarp šilumos vartotojų, kurie tų kainų svyravimus pajaučia gaudami didesnes sąskaitas už šildymą. Aptarus šilumos energijos sektoriaus ypatumus, šilumos kainą lemiančius veiksnius, nustatymo metodiką bei institucijas, reguliuojančias šilumos ūkį, buvo išnagrinėti pagrindiniai veiksniai, turintys įtakos šilumos kainų pokyčiams. Atlikta šilumos kainos struktūrinė analizė. Įvertinta Šiaulių termofikacinės elektrinės teikiama nauda gyventojams. Atliktas šilumos kainos tarifo ir alternatyvaus kuro šildymui vidutinių kainų tyrimas. Pateikta mokėjimų už šilumą analizė, nagrinėjant atskiras pastatų grupes, daugiabučių pasiskirstymą pagal bendrijas ir renovuotus bei nerenovuotus namus. Vertinant šilumos kainą lemiančius veiksnius atlikta daugialypė regresinė analizė. Išnagrinėjus teorinius ir praktinius daugiabučių namų šilumos kainų aspektus, pateikiamos baigiamojos darbo išvados ir siūlymai kaip sumažinti šilumos kainas. Darbą sudaro 6 dalys: įvadas, du skyriai, išvados ir rekomendacijos, literatūros sąrašas. Darbo apimtis – 69 p. teksto be priedų, 7 lent., 16 pav., 43 šaltiniai.
The final bachelor‘s paper deals with reasons of the heat price changes and the posibilities of reducing them in Siauliai city. The heat supply is a service of the public interest, which is used by many population of the city. The rising prices of district heating sector services, raises the dissatisfaction among users of the heat fluctuations in the consciousness of those receiving the higher heating bills. After dealing with the thermal energy sector, the heat price determinants, detection methods and institutions to regulate the heating system, the major factors affecting the heat price changes were explored. Structural analysis of the rates of heat was accomplished. The benefit for people of the thermal power plant in Siauliai was assessed. Also the heat price tariff and alternative fuel for heating medium-price test was accomplished. Presented payments for heat analysis, examining the separate groups of buildings, multi-distribution of communities and renovated houses. In assessing the determinants of the price of heat conducted multiple regression analysis. The examination of the theoretical and practical aspects of the apartment home prices, the conclusions of the work and proposals on how to reduce the heat are presented in the final work. The paper consist of the followings 6 parts: introduction, two sections, conclusions and recommendations, list of references. Amount of paper – 69 pages of text without annexes, 7 tables, 16 illustrations, 43 sources.

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Paškauskas, Artūras. "Šilumos atgavimo funkcijos galimybių šalčio mašinose įvertinimas ir pritaikomumas Lietuvos klimatinėmis sąlygomis". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130129_192437-23743.

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Baigiamajame magistro darbe nagrinėjama tiesioginė šilumos atgavimo funkcija iš šilumos siurblio darbo ciklo ir jos pritaikomumas Lietuvos klimatinėmis sąlygomis. Apžvelgiami naudojamų šalčio mašinų tipai, technologiniai tiesioginio šilumos atgavimo inžineriniai sprendmiai. Taip pat detaliai paaiškinamas šilumos siurblio darbo ciklas ir tiesioginio šilumos atgavimo funkcijos veikimo principas. Taip pat šilumos atgavimo founkcija nagrinėjama konkrečiame jau egzistuojančiame administracinės paskirties pastate, kuriame sumontuota vandeninė šalčio mašina. Nustatomas šalčio mašinos darbo režimų grafikas skaičiuojamąjį Liepos mėnesį. Dviejomis nepriklausomomis kompiuterinėmis programomis sumodeliuojami šalčio mašinos freono konturų darbo ciklai. Pagal gautus rezultatus parenkami ir sumodeliuojami šilumos atgavimo šilumokaičiai ir randamos įmanomos atgauti šilumos galios ir šilumos kiekiai, kurie palyginami su pastato karšto vandens poreikiais ir atliekamas ekonominis šilumos atgavimo funkcijos vertinimas. Gauti rezultatai patvirtina, kad tokio tipo šilumos atgavimas didina pastato energijos vartojimo efektyvumą ir padeda taupyti pinigus. Taip pat nustatyta, kad Lietuvos klimatinėmis sąlygomis šilumos atgavimas įmanomas tik šiltuoju metų sezonu, kai pastate yra vėsos poreikis, tačiau nepaisant to, metiniai sutaupymai yra pakankamai dideli, todėl tiesioginis šilumos atgavimas yra efektyvi mikroklimato sistemų optimizavimo priemonė.
In this Master thesis a direct heat recovery option on the air cooled chiller and its availability in Lithuanian climate has been investigated. Also the review of chiller range, direct heat recovery technological issues and direct refrigerant vapor compression cycle has been explained in detail. Also the heat recovery option has been investigated in the specific administrative building with the chiller already installed. Chiller cooling chart has been calculated for the selected time period – a month of July. Chiller refrigerant circuits were modeled by using two independent computer applications. In accordance with the calcultated results, plate heat exchangers were designed. Possible amount of recovered heat was found and compared with building‘s heat demand for hot domectic water supply. The economical evaluation of heat recovery option was carried out. The results confirmed that the heat recovery option discussed in the thesis can increase energy consumption efficiency. Despite the fact that heat recovery in Lithuanina climate is only possible during the warm season, annual savings on energy consumption are sufficiently high to make the heat recovery measure an attractive option.

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Vaičikauskaitė, Aiva. "Oro taršos tyrimai centralizuoto ir individualaus šilumos tiekimo rajonuose Šiaulių mieste". Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100903_001300-94852.

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Oro tarša viena iš aktualių šių laikų problemų. Didelį poveikį oro taršai daro šildymo sezono metu neracionaliai naudojama šilumos energija namų šildymui. Dėl to daromas poveikis net tik žmonių sveikatai, bet ir aplinkai. Oro taršos tyrimai buvo atliekami centralizuoto ir individualaus šilumos tiekimo rajonuose Šiaulių mieste. Tyrimų rezultatai lyginami su aplinkos oro užterštumo normomis, kurios leidžia pateikti išvadas bei pasiūlymus racionaliam šiluminės energijos panaudojimui. Mažinant oro taršą Šiaulių mieste būtina skatinti visuomenę kuo daugiau naudoti atsinaujinančius energijos išteklius šilumos gamybai.
Air pollution is one of the big problem this time. Significant impact on air pollution has improperly used during the heating season, heat energy for heating homes. So impact human health and the environment. Air pollution studies was carried out in central and individual heating zones in the city of Siauliai. Test results are compared to ambient air pollution rules, which allow for conclusions and suggestions for the rational use of thermal energy. It is necessary to encourage the public to use the heat produced from renewable energy sources to reduce air pollution in the city of Siauliai.

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Bareika, Paulius. "Vėdinimo įrenginių su integruotais šilumos siurbliais projektavimas, tyrimas ir analizė". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130620_153425-09930.

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Magistro baigiamajame darbe nagrinėjami vėdinimo įrenginiai su integruotais šilumos siurbliais. Darbe atliekama tokios rūšies įrenginių literatūros apžvalga. Apžvelgiami šilumos siurblio komponentai, darantys didžiausią įtaką jo darbui. Darbo metu atlikti įrenginių projektavimo ir konstravimo darbai. Pateikiamos projektavimo rekomendacijos. Lyginami skirtingi kompresorių galios moduliacijos principai. Nagrinėjami įrenginių darbo režimai, kylančios problemos eksploatacijos metu, ieškomi problemų sprendimų būdai. Pateikiamos kintamo sukimosi greičio kompresorių galių moduliacijos ribos. Atliekamos energinė ir ekserginė analizės pagal eksperimentinio bandymo duomenis. Nustatomi realūs termodinaminio efektyvumo ir naudingumo koeficientai. Jautrumo analizės metu atliekami elektrinio šildytuvo efektyvumo ir naudingumo skaičiavimai. Pateikiami rezultatai, išvados ir rekomendacijos tokios rūšies įrenginių tobulinimui ir tolimesniam vystymui. Darbo apimtis – 94 psl. teksto be priedų, 66 iliustr., 7 lent., 43 bibliografiniai šaltiniai.
Master's thesis examines air handling units with integrated air source heat pumps. Literature review about this type of units was carried out. An overview of mostly important heat pump‘s components are given. Thesis was an opportunity to design, construct and analyze these units. Different heat pump‘s operation modes examined and main issues turned out. Based on experimental data variable speed compressor's capacity modulation results defined. Moist air thermodynamic calculations have been made and air handling unit with integrated air source heat pump experimental energy and exergy efficiency was defined. Sensitivity evaluation changing heat pump with electric heater carried out. The main recommendation provided for units designing and further development. Thesis consist of 94 p. text without appendixes, 66 pictures, 7 tables, 43 bibliographical entries.

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Brack, Stefan [Verfasser]. "Time-resolved Transient Convective and Conjugate Heat Transfer Experiments Using IR Thermography / Stefan Brack". München : Verlag Dr. Hut, 2020. http://d-nb.info/1219476323/34.

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Poškus, Vytautas. "Plėšriųjų žvėrių ir tetervinų populiacijos būklė Praviršulio tyrelio valstybiniame botaniniame – zoologiniame draustinyje 2008 - 2009 metais". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090615_115055-29971.

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Magistro darbe tiriama plėšriųjų žvėrių ir tetervinų populiacijos būklė. Tyrimo objektas – Radviliškio rajone esančiame Praviršulio tyrelio valstybinio botaninio - zoologinio draustinyje sutinkami plėšrieji žvėrys ir tetervinai. Darbo tikslas - nustatyti plėšriųjų žvėrių ir tetervinų populiacijos būklę Praviršulio tyrelio valstybiniame botaniniame – zoologiniame draustinyje. Siekiant darbo tikslo buvo iškelti tokie uždaviniai: 1) ištirti draustinio plėšriųjų žvėrių rūšinę sudėtį, atskirų rūšių gausą bei tankį; 2) apskaičiuoti tetervinų gausą bei tankį; 3) apskaičiuoti plėšrūnų ir aukų santykį bei jo atitikimą ekologiniam santykiui; 4) ištirti plėšriųjų žvėrių ir tetervinų populiacijos dinamiką. Tyrimo metodai - Lietuvos ir užsienio autorių mokslinės literatūros analizė bei sintezė, duomenų grupavimas, statistiniai metodai, grafinis vaizdavimas. Tyrimo laikotarpis apima 2008 -2009 metus. Darbo rezultatai: buvo išstudijuota lietuvių ir užsienio autorių moksliniais darbai bei periodinė literatūra apie medžiojamosios faunos elgseną įtakojančius veiksnius, buvo ištirta draustinio plėšriųjų žvėrių rūšinė sudėtis, apskaičiuota žvėrių gausa, bendras tankis, ištirta žvėrių populiacijos dinamika. Gauti tokie rezultatai: 2008-2009 metais plėšriųjų žvėrių gausa didėjo. Apskaičiuoti plėšriųjų žvėrių ir aukų santykiai gana labai neatitiko ekologinių. Tetervinų gausa 2008-2009 metais sumažėjo.
Master's work examined prey animals, and heath-cock population of the state. Object of research – Carnivora and heath-cocks met in the territory of Praviršulis tyrelis public botanical - zoological reservation in Radviliškis district. Purpose of the Paper – estimate the state of Carnivora and heath-cocks in the Praviršulis tyrelis public botanical - zoological reservation. Achieving the purpose the following goals were raised: 1) to determine the varietal composition, abundance and density of certain species of the Carnivora in the reservation; 2) to determine the abundance and density of heath-cocks in the reservation. 3) to determine the ratio between predators and preys, and its conformity with ecological ratio; 4) to explore the dynamics of Carnivora and the heath-cock populations. Methods of research - analysis and synthesis of Lithuanian and foreign scientific literature, data grouping, statistical methods, graphical presentation. The research period is the years 2008 - 2009. The results: there was studying scientific works of Lithuanian and foreign authors and periodic literature about the factors influencing the behaviours of fair game, there was determined the abundance of animals, general density, determined the dynamics of animals population. Obtain the following results: 2008-2009, increased the abundance of prey animals. Calculate prey animals and the relationship between the victims is quite inconsistent with the ecological. Hheath-cocks abundance declined in 20... [to full text]

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Boztepe, Sinan. "Understanding of infrared heating for thermoforming of semi-crystalline thermoplastics". Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2018. http://www.theses.fr/2018EMAC0017.

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Les thermoplastiques et les composites thermoplastiques sont généralement mis en œuvre par thermoformage et sont alors le plus souvent préchauffés en utilisant un chauffage IR. L’avantage du chauffage radiatif est qu'il permet de chauffer les polymères à cœur grâce au caractère semi-transparent des polymères. Néanmoins, dans le cas des polymères semi-cristallins, le chauffage radiatif est affecté par la structure cristalline et cette thèse a donc eu pour objectif d’améliorer la compréhension de l'interaction entre la structure cristalline et les propriétés optiques dans le but de proposer un modèle prédictif de chauffage de thermoplastiques semi-cristallins.Cette étude répond à une problématique industrielle relative au contrôle de la température des thermoplastiques semi-cristallins dans les procédés recourant au chauffage radiatif. L’optimisation de ces procédés requiert un code de calcul suffisamment robuste pour permettre une bonne prédiction du champ de température tout en conservant des temps de calcul acceptables. Une approche combinée expérimentale et numérique a ainsi été proposée dans le but de modéliser la capacité d’absorption du rayonnement thermique de milieux polymères semi-cristallins et le transfert de chaleur par rayonnement avec changement des phases de cristaux/amorphe. Ces travaux se concentrent sur le PEHD, qui présente un intérêt particulier pour l’entreprise Procter&Gamble.Dans cette thèse, après avoir établi une revue bibliographique mettant en avant les couplages existants entre les phénomènes de diffusion optique, la microstructure des polymères semi-cristallins et la température, une caractérisation et une analyse poussées des propriétés radiatives de deux polyéthylènes sont proposées. Les analyses morphologiques et optiques ont été réalisées à température ambiante et dans des conditions de chauffage afin d’identifier les formations cristallines à l’origine de la diffusion optique dans des polymères semi-cristallins et l’évolution de ce couplage au cours du chauffage. A travers ce travail de recherche, un coefficient d’extinction spectral thermo-dépendant a été proposé afin de décrire le caractère optiquement hétérogène du milieu semi-cristallin par un milieu homogène équivalent. Sur la base de la caractérisation de la capacité d'absorption du rayonnement thermique, un modèle thermique conducto-radiatif thermo-dépendant a été développé. Afin d’évaluer la précision de la modélisation, une méthodologie expérimentale spécifique a été proposée pour mesurer la température de surface par thermographie IR dans le cas du PEHD semi-transparent. L’étape finale a consisté à confronter les résultats issus des simulations numériques basées sur cette modélisation à plusieurs campagnes de mesures expérimentales. Les résultats de ces travaux démontrent la forte influence de la structure morphologique des polymères semi-cristallins sur les transferts de chaleur radiatifs
Thermoplastics and thermoplastic composites are promising candidates for manufacturing highly cost- effective and environmental-friendly components in terms of rapid forming and recyclability. Thermoforming is extensively used for the processing of thermoplastics where IR heating is widely applied. The major advantage of radiative heating is that the significant portion of radiation penetrates into the semi-transparent polymer media.This thesis focuses on understanding of IR heating of semi-crystalline thermoplastics which aims to analyze the driven mechanisms for radiation transport in optically heterogeneous unfilled semi-crystalline polymer media. Considering the relatively narrow thermoforming window of semi-crystalline thermoplastics, accurate temperature control and close monitoring of temperature field is crucially important for successful forming process. It is thus required to build a numerical model robust enough to allow a good prediction of the temperature field while maintaining acceptable calculation times. In this research work, a combined experimental-numerical approach has been proposed which enables both to characterize the radiation absorption capacity of semi-crystalline polymer media and, to model the radiation heat transfer considering the crystalline/amorphous phases change under heating. This research focuses on a particular polymer - highly crystalline HDPE- which is supported by Procter & Gamble.In this thesis, the literature was reviewed at first for highlighting the existing coupled relation between the optical properties and the crystalline structure of semi-crystalline polymers. The role of crystalline morphology on the optical properties and optical scattering of two type of polyethylene, namely HDPE and LLDPE, were addressed. More specifically, the morphological and optical analyses were performed at room temperature and under heating to determine: which crystalline formations are responsible for optical scattering in semi-crystalline polymer media and, how does their coupled relationship evolve under heating conditions? Hence, one of the key contributions of this research is on establishing a temperature-dependent spectral extinction coefficient of HDPE allowing to describe temperature- dependent radiation absorption capacity of its semi-crystalline medium and, to model radiative transfer considering an equivalent homogeneous medium. Based on the characterization of radiation absorption capacity of semi-crystalline media, a temperature-dependent conduction-radiation model was developed. In order to assess the modeling accuracy, an experimental methodology was proposed for non-invasive surface temperature measurements via IR thermography on semi-transparent polymer media. The final step was to compare the results of numerical simulations with the several IR heating experiments to prove the strong influence of the crystalline morphology on heat transfer

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Sanches, José Afonso. "Understanding the dynamics of a tunnel oven : Use of infrared sensors to measure the temperature of the conveyor belt in a tunnel oven used in bread production". Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70363.

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During the continuous production of bread sometimes there are problems that lead to interruptions in the production and consequently to quality problems. One such problem is the bread burning in the contact area between the bread and the conveyor belt. In order to understand the problem and to know how to quantify it, it is necessary to understand what a thermodynamic system is and what types of systems exist, how the various types of heat transfer are processed, how to measure the temperature of an object by infrared radiation and some mathematical methods such as the least square root method. Temperature measurements were planned and carried out. The goal with the first experiment was to understand how the temperature of the conveyor belt varies during an interruption. All the other tests were done to investigate the effects of different solutions in the temperature variation of the belt. According to the results, the best solution is to turn off the oven during an interruption and the worst to spray the belt with water. To spray the belt with water may be a better solution than these results shows, but it is very affected by other problems, like depositions of limestone on the nozzles. A lot more solutions could be found but due to the time available, it was not possible to investigate all the variables/solutions in the process. A long-term study would help understand much more within the regulation of the industrial baking process.
Under kontinuerlig produktion av bröd finns det ibland problem som leder till avbrott i produktionen och kvalitetsproblem. Ett sådant problem är att brödet blir bränt i kontaktytan mellan brödet och transportbandet. För att förstå problemet och veta hur man kvantifierar detta, är det nödvändigt att förstå vad ett termodynamiskt system är och vilka typer av system finns, hur olika typer av värmeöverföring sker, hur man mäter temperatur med hjälp av infraröd strålning och några matematiska metoder som minst kvadratrotsmetoden. Temperaturmätningar planerades och genomfördes. Målet med det första experimentet var att förstå hur transportbandets temperatur varierar under ett huppehåll. Alla andra tester utförades för att undersöka effekterna av de olika lösningarna i bandets temperaturvariation. Enligt resultaten är den bästa lösningen att stänga av ugnen under ett uppehåll och det värsta att spreya bältet med vatten. Att spreya bältet med vatten kan vara en bättre lösning än vad resultaten visar, men det påverkas mycket av andra problem, som avsättningar av kalksten på munstyckena. Många fler lösningar kunde hittas men det var inte möjligt att undersöka alla variabler / lösningar i processen på grund av tillgänglig tid. En långsiktig studie skulle hjälpa till att förstå mycket mer inom regleringen av industriell bakning.

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Pulicani, Emeline. "Voir et entendre en egypte ancienne : les dieux Ir et Sedjem". Thesis, Lille 3, 2015. http://www.theses.fr/2015LIL30056.

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Ir et Sedjem forment un couple divin complémentaire et indissociable qui apparaît au Nouvel Empire et qui perdure jusqu'à l'époque romaine. Le premier volume regroupe toute la documentation nécessaire à cette étude. Quatre-vingt-neuf documents mentionnant Ir et Sedjem ont été recensés et classés par type puis par ordre décroissant du nombre d'attestations : les temples (rangés chronologiquement et du Sud au Nord), les papyrus et les bandelettes de momies (ordonnés par musées puis par numéro d'inventaire) et enfin les objets divers (classés par époque). Chaque fiche créée au sein de notre corpus est composée de cinq entrées : l'emplacement de l'attestation d'Ir et Sedjem dans le temple, le papyrus, la bandelette ou l'objet, la datation, la description détaillée suivant la nature et l'état de conservation du document ; la bibliographie et le contexte d'apparition qui indique si Ir et Sedjem sont représentés, simplement cités et/ou s'ils tiennent un discours. Enfin, sur la page paire sont regroupées la ou les différentes illustrations. Le deuxième volume est consacré à la synthèse de notre étude sur Ir et Sedjem divisée en quatre chapitres. Le premier traite des noms de nos deux divinités notamment de leurs graphies respectives afin d'établir une translittération définitive et une traduction de leurs noms. Leur iconographie a été étudiée ensuite (attitudes, perruques, signes-emblèmes, vêtements, éléments de parure, barbe postiche) ainsi que les quelques cas particuliers relevés (zoomorphie totale ou partielle, possible aspect féminin, symbiose éventuelle) et enfin ,leurs attributs ont été traités. La troisième partie de notre développement est consacrée à l'analyse des liens qui unissent Ir et Sedjem aux autres divinités du panthéon égyptien. Avant de procéder à l'étude des différentes fonctions de nos deux divinités, un inventaire de leurs épithètes, de leurs discours et des offrandes qu'ils reçoivent a été établi. Nous avons également examiné les divers emplacements sur lesquels ils sont mentionnés dans les temples. Enfin, nous avons terminé notre recherche en proposant un bref examen sur les liens indirects qui existent entre Ir et Sedjem et le Ka royal, les deux vautours In-nout et Sedjemet dans le Mythe de l'Oeil du Soleil et les 14 Kaou de Rê
Ir and Sedjem form a complementary and inseparable divine couple that appears in the New Kingdom, which lasted until the Roman period. The first volume includes all necessary documentation in this study. Eighty-nine documents mentioning Ir and Sedjem were listed and classified by type then in decreasing order of the number of certificates : temples (tidied up chronologically and from South to North), papyri and strips of mommies (ordered by museums then by number of inventory) and finally the diverse objects (classified by time). Each file created within our corpus consists of five entries : the location of the certificate of Ir and Sedjem in the temple, papyrus, the strip or object ; the dating ; the detailed description following the nature and the state of preservation of the document ; the bibliography and the context of appearance which indicates if Ir and Sedjem are represented, even-numbered page are grouped one or several various illustrations. The second volume is devoted to the synthesis of our study on Ir and Sedjem divided into four chapters. The first deals with names of our two deities includong their respective written form in order to establish a definitive transliteration and translation of their names. Their iconography was then studied (attitudes, wigs, signs-emblems, clothes, elements of finery, false beard) as well as the few particular cases found (total or partial zoomorphic shape, possible feminine aspect, prospective symbiosis) and finally, their attributes were handled. The third part of our development is dedicated to the analysis of the links between Ir and Sedjem and the other divinities of the Egyptian pantheon. Before proceeding to the study of the various functions of our two divinities, an inventory of their epithets, their discourse and the offering which they receive was established. We also examined the diverse locations on which they are mentioned in temples. Finally, we completed our research by proposing a brief review of the indirect links which exist between Ir and Sedjem and royal Ka, the both vultures In-nout and Sedjemet in the Myth of th Eye of the Sun and the 14 Kaou of Rê

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Pedotto, Cristina. "Using IR thermography to determine the heat flux removed by spray cooling a high-temperature metallic surface". Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1044.

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Bougeard, Daniel. "Etude expérimentale du transfert thermique couplé au sein de géométries complexes : application aux échangeurs de chaleur". Valenciennes, 1997. https://ged.uphf.fr/nuxeo/site/esupversions/32ad393b-fdf6-43c3-803f-5411e53c570f.

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Ce travail consiste à analyser les échanges thermiques couplés au sein des échangeurs de chaleur à ailettes planes munies de promoteurs de turbulence. Une étude bibliographique permet de bien appréhender les phénomènes physiques responsables de l'augmentation du transfert convectif à l'aide de promoteurs de turbulence. Une méthodologie d'étude est ensuite proposée afin de déterminer les performances thermiques et aérauliques des échangeurs. Une méthode utilisant une efficacité de tube permet de déterminer la puissance thermique dissipée dans les échangeurs réels à partir d'essais effectués sur des maquettes. La perte de charge est également mesurée sur un banc expérimental spécifique. Un dispositif de thermographie infrarouge est utilisé pour une étude locale de la densité de flux surfacique au niveau des ailettes, en tenant compte du couplage conducto-convectif. Afin d'améliorer les résolutions spatiale et thermique du dispositif de thermographie, des techniques spécifiques de traitement du signal sont développées. Enfin les résultats obtenus sont validés par la comparaison des performances globales de l'échangeur, déterminées par la méthode proposée, avec des essais effectués sur des échangeurs réels et des corrélations de la bibliographie. Les densités de flux surfaciques mesurées localement sont comparées à des résultats issus de simulations numériques.

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Torstensson, Anton. "Värmekamera i fysikundervisning : En undersökning av hur värmekameran kan stimulera inlärningen av värmerelaterade fenomen". Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-322206.

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Värmelära upplevs ofta som ett abstrakt område i gymnasiefysiken och elever tenderar att tolka känseln som en termometer. Värmelära kan därmed bli en tuff utmaning för många elever. Genom att introducera värmekameror i undervisningen ges elever möjligheten att se annars osynliga värmefenomen. Eftersom värmekameran inte ännu blivit etablerad i undervisningen finns det ett intresse att studera elevernas interaktion med värmekameran. Syftet med studien är att undersöka hur interaktionen ser ut och hur värmekameran kan hjälpa elever i begreppsbildandet av värmerelaterade fenomen. Denna studie har gjorts på ca 140 elever som går sitt första år på det naturvetenskapliga programmet på en gymnasieskola i Mellansverige. Eleverna fick utföra en laboration designad enligt prediction-observation-explanation-metoden. Laborationen innehöll tre stationer där de centrala begreppen var värmeledning, stöt och friktion. Eleverna använde en värmekamera som hjälpmedel för att förklara de olika fenomenen. Elevernas interaktioner vid laborationen dokumenterades med video- och ljudupptagning i syfte att ge grund för en kvalitativ analys. Analysen av materialet kom att handla om tre delar: hur eleverna resonerar kring värmeledning, respektive friktion och stöt, och hur värmekameran kan stimulera det kreativa tänkandet hos eleverna. Det visade sig att många elevgrupper kom långt i det makroskopiska och en bra bit i det mikroskopiska resonemanget kring värmeledning genom att tillämpa en modell av fria elektroner i metall de hade lärt sig från kemin. De flesta grupperna hade svårt att resonera kring energiomvandlingar vid stöt både på en makroskopisk och mikroskopisk nivå. Det kreativa undersökandet resulterade i en röra. Värmekameran lockar elevernas nyfikenhet, ger ”disciplinary affordance” och stimulerar dem till ”instant inquiry”. När eleverna gick utanför instruktionerna och bedrev egna undersökningar resulterade det i en röra då de prioriterade bort sina nykonstruerade hypoteser.
Thermodynamics is often perceived as an abstract field in secondary school physics. Thermodynamics can thus be a tough challenge for many students. By including thermal imaging cameras in teaching, students are given the opportunity to see otherwise invisible thermal phenomena. Since the infrared camera has not yet been established in teaching, there is an interest in studying the interaction between students and the thermal imaging camera. The purpose of this study is to investigate the interaction between student and the infrared camera and to see how the infrared camera can help students in the conceptual formation of heat-related phenomena. The study included about 140 students attending their first year on the science program at an upper secondary school in central Sweden. The students had to perform laboratory experiments designed according to the prediction-observation-explanation method. The laboratory experiments consisted of three stations where the key concepts were heat conduction, collision and friction. Students took help of an infrared camera to explain the various phenomena. The students' interactions at the lab were documented with video and audio recording in order to set the basis of a qualitative analysis. The analysis of the material consisted of three parts: how students reason concerning heat conduction, their reasoning concerning dissipative processes as friction and collision, and how the infrared camera can stimulate the students' creative thinking. Many student groups were successful in the macroscopic and quite successful in the microscopic reasoning regarding heat conduction by applying a model of free electrons in the metal which they had learned in chemistry class. Other studies have shown that students find it hard explaining heat conduction and that they tend to interpret the physical touch as a thermometer. The group that examined friction and collision found it difficult explaining the transformation from kinetic energy into thermal energy in collision at both the macroscopic and microscopic level. The creative investigation resulted in a mess. The infrared camera attracts students' curiosity, gives ”disciplinary affordance” and stimulates them to ”instant inquiry”. When the students went beyond their instructions and conducted own investigations it resulted in a mess when they prioritized away the recently created hypotheses.

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Chettaf, Aïssa. "Contribution à l'étude du séchage par rayonnement infrarouge : Application au séchage en couche mince d'une enduction". Valenciennes, 1994. https://ged.uphf.fr/nuxeo/site/esupversions/9a259158-201e-4807-bac7-56fdaf6a482b.

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Dans cette étude, nous nous intéressons particulièrement au séchage d'une enduction (colle à eau) soumise à des contraintes radiatives et convectives. L'apport d'énergie nécessaire à la vaporisation du solvant provient essentiellement d'un émetteur de rayonnement infrarouge. Dans un premier temps, nous avons procédé à la caractérisation physico-chimique du produit, en l'occurrence une colle à papier. Quelques propriétés intrinsèques ont été déterminées au laboratoire pour être utilisées dans une modélisation des transferts de matière et de chaleur et enfin le choix de l'émetteur infrarouge utilisé dans toutes nos opérations de séchage. Dans une deuxième partie, l'émetteur infrarouge a fait l'objet d'une caractérisation thermique. La technique utilisée est la thermographie infrarouge pour déterminer le champ de température de la plaque. A partir du champ de température, nous avons résolu numériquement l'équation inverse du bilan énergétique pour déterminer les densités de flux. L'analyse des résultats expérimentaux de séchage nous a permis de vérifier la validité du modèle, purement diffusif, décrivant d'une manière satisfaisante le comportement de la colle. Les résultats de caractérisation de l'émetteur nous ont permis de déterminer la disposition géométrique de plusieurs émetteurs afin d'avoir un séchage relativement homogène sur tout le produit. L'ensemble des résultats est utilisé pour concevoir une installation de séchage par rayonnement infrarouge qui sera expérimentée sur site industriel.

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Douellou, Corentin. "Fatigue des aciers élaborés par fabrication additive L-PBF : approche thermomécanique et comparaison de stratégies de fabrication". Thesis, Université Clermont Auvergne‎ (2017-2020), 2020. http://www.theses.fr/2020CLFAC019.

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La thèse de doctorat porte sur les performances en fatigue des aciers fabriqués par fusion laser sur lit de poudre (L-PBF). L'objectif de l'étude est de développer une méthode pour la caractérisation rapide et fiable de la limite de fatigue d’un matériau en utilisant la thermographie infrarouge (IR). Des essais préliminaires de fatigue conventionnelle ont été effectués, révélant deux populations distinctes parmi les éprouvettes fabriquées selon leur emplacement sur le plateau de fabrication. Ensuite, des tests de fatigue instrumentés par caméra IR ont été traités en utilisant la technique de reconstruction de la source de chaleur pour mesurer la dissipation mécanique due aux dommages causés par la fatigue. Un modèle statistique a ensuite été proposé pour identifier la limite de fatigue du matériau. Enfin, une application pratique a été réalisée pour comparer différentes stratégies de fabrication utilisant la même poudre d'acier maraging, ainsi que différents aciers (maraging, L40 et W360). Les résultats ouvrent des perspectives pour l'optimisation rapide du processus d'impression vis-à-vis des performances de fatigue des pièces produites
The PhD thesis deals with the fatigue performance of steels manufactured by Powder Bed Fusion using a laser beam (L-PBF). The objective of the study is to develop a method for the rapid and reliable characterization of the produced material’s fatigue limit using infrared (IR) thermography. Preliminary conventional fatigue tests were performed, revealing two distinct populations among the printed specimens depending on their locations on the building plate. Next, fatigue tests instrumented by IR camera were processed using heat source reconstruction to measure the mechanical dissipation due to fatigue damage. A statistical model was then proposed to identify the fatigue limit of the material. Finally, a practical application was performed to compare different manufacturing strategies using the same powder of maraging steel, as well different steels (maraging, L40 and W360). The results open perspectives for the rapid optimization of the printing process with respect to the fatigue performance of the parts produced

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Benevides, Ferreira José Flavio. "La mise au point de méthodes thermiques et spectrométriques pour la caractérisation des catalyseurs pour le stockage de CO2". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00858419.

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La capture de CO2 par adsorption sur des solides poreux (adsorbants) est une alternative prometteuse en raison de sa sélectivité et de sa faible consommation d'énergie. Nous avons étudié l'adsorption in-situ de CO2 sur des adsorbants solides en combinant la spectroscopie infrarouge par réflexion diffuse (DRIFT) avec la thermographie infrarouge afin de mieux comprendre les mécanismes d'interaction CO2-adsorbant et ainsi optimiser sa captation dans des procédés de capture en post-combustion. La thermographie IR est utilisée pour détecter la source de chaleur transitoire provenant de la surface de l'adsorbant au cours de l'adsorption de CO2. Un modèle de transfert de chaleur a été développé afin d'estimer les chaleurs d'adsorption. Un mini réacteur conçu pour la DRIFT nous a permis d'identifier les espèces adsorbées et d'étudier leur évolution sur la surface de l'adsorbant selon la température et l'atmosphère environnante. Enfin, le couplage d'informations provenant des deux approches nous a permis l'investigation haut-débit des paramètres clefs pour le choix des adsorbants les plus performants.

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Zeman, Martin. "Pracoviště termovize". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219060.

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This thesis contains an overview of physical principles concerning thermography and infra-red sensing, and a specification of a measuring instrument in a measurement system. Next, there are some particular examples of IR sensing applications. In the second part there is a thermal camera market research including individual manufacturers and models with their attributes and prices. There is a closer view of the thermal camera used for this thesis (Guide EasIR-4). In the end of the thesis there are some drafts of computer vision subject tasks (or practices), including workplace designs and solutions, and three task suggestions for bachelor or diploma theses including solution verifications.

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Lahbabi, Khalid. "Etude et realisation d'un dispositif de mesure, dans le spectre infrarouge, de l'emissivite des materiaux opaques". Paris 6, 1986. http://www.theses.fr/1986PA066115.

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Mesure directe de l'emissivite spectrale directionnelle d'echantillons dans le domaine spectral 3 microns a 11 microns en fonction de l'angle d'observation, de la longueur d'onde du rayonnement et de la temperature. Possibilite de mesure indirecte par l'intermediaire de la brdf

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Žvingilaitė, Erika. "Kogeneracijos diegimo galimybės mažuose Lietuvos šilumos ūkiuose". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2004. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2004~D_20040625_005600-43599.

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After closure of Ignalina nuclear power plant its capacity is going to be replaced by large-scale Lithuania’s power plants burning imported fossil fuel. This can lead to high energy system dependency from foreign countries, supplying mostly gas, and to the increase of environmental pollution. Meanwhile, some of small Lithuanian district heating companies suffer from high heat prices and consumers debts. Heat prices for consumers in small districts are by approximately 30 % higher, than for consumers in large cities. Needed electricity capacity could be partially replaced and district heating prices could be reduced by introducing small-scale cogeneration. This report is dealing with cogeneration technologies, their advantages and drawbacks. The possibilities and obstacles for implementation of these technologies in Lithuania are examined. The benefits from introduction of these technologies versus condensing power plants are analyzed. These issues have been assessed by simulating combined heat and power production in selected district heating company. There is evaluated the impact of electricity prices on the economy of different scenarios and heat prices. Finally, the conclusions about the feasibility of cogeneration implementation and the sufficiency of support schemes are made.

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Benzerrouk, Souheil. "Feasibility study of infrared detection of defects in green-state and sintered PM compacts". Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0427104-165155.

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Thesis (M.S.)--Worcester Polytechnic Institute.
Keywords: powder metallurgy; material evaluation; thermal imaging; NDE; IR radiation and detection; nondestructive testing; thermography; infrared imaging. Includes bibliographical references (p. 86-88).

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Harajli, Zeinab. "Synthesis, characterisation and thermal evaluation of a new generation of metalised ceramic materials". Thesis, Lyon, 2022. http://www.theses.fr/2022LYSEI016.

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Une gestion thermique efficace est souvent considérée comme une étape clé vers un système technologique réussi. L'élimination rapide de l'excès de chaleur, des systèmes électroniques exposés à des températures extrêmes, améliore la fiabilité et empêche la défaillance prématurée de ces systèmes. De nos jours, les approches habituelles, pour évacuer la chaleur et maintenir le système à une température souhaitée, consistent à utiliser un dissipateur thermique à semi-conducteur ou un système complexe de contrôle de vitesse de ventilateur qui repose sur une mesure continue de la température. Cependant, l'optimisation d'un dissipateur thermique à semi-conducteur très efficace nécessite le contrôle de diverses propriétés intrinsèques et extrinsèques à différentes échelles, car le flux thermique macroscopique et le transport de chaleur dépendent des propriétés vibrationnelles microscopiques. En outre, l'utilisation généralisée de dissipateurs thermiques à semi-conducteurs hautement efficaces nécessite la capacité de les métalliser et de former des structures multicouches. En raison de ses vitesses de groupe de phonons élevées, le nitrure d'aluminium (AlN) semble être l'un des meilleurs candidats pour la fabrication de dissipateurs thermiques à semi-conducteurs efficaces. Dans cette thèse, nous avons comme objectif de développer une nouvelle technologie d’un substrat à base de la structure Métal/AlN/Métal à haute diffusivité thermique pour des applications à haute température (>300°C). Cette thèse vise à développer des technologies d'électronique de puissance hautement efficaces, intégrées et fiables fonctionnant à haute température pour l'automobile, l'aéronautique et l'énergie. Dans un premier temps, nous avons élaboré des films minces de molybdène pour métalliser le nitrure d'aluminium et synthétiser nos nouveaux substrats de dissipateur thermique pour les modules de puissance. Ensuite, nous avons optimisé les dispositifs établis en étudiant leurs propriétés physico-chimiques et en mettant l'accent sur leurs performances thermiques. Enfin, nous avons étudié les performances des échantillons en utilisant une imagerie souterraine et tout en augmentant la température afin de surveiller la formation de défauts. La caractérisation thermique et l'imagerie souterraine des échantillons ont été effectuées à l'aide de notre nouvelle configuration de déviation de faisceau photo-thermique, dans laquelle nous installons un laser IR pour chauffer les échantillons et qui génère des bosses thermiques qui sont mesurées par des faisceaux de sonde déviant à différents endroits de l'échantillon
Efficient thermal management is often considered a key step towards a successful technological system. The fast removal of excess heat from electronic systems exposed to temperature extremes improves the reliability and prevents the premature failure of these systems. Nowadays, the usual approaches to evacuate heat and maintain the system at the desired temperature consist in using a semiconductor heat sink or a complex fan speed control system that relies on continuous temperature measurement. However, the optimization of a highly efficient semiconductor heat sink requires the control of diverse intrinsic and extrinsic properties at different scales because the macroscopic thermal flow and heat transport depend on microscopic vibrational properties. Besides, widespread use of highly efficient semiconductor heat sinks requires the ability to metalize them and form multilayer structures. Due to its high phonon group velocities, Aluminium Nitride (AlN) appears to be one of the best candidates for the manufacturing of efficient semiconductor heat sinks. In this PhD. thesis work, we intend to develop a new substrate technology Metal/AlN/Metal structures with high thermal diffusivity for integrated power systems for high-temperature applications (>300°C). This PhD. Aims at developing highly efficient, integrated and reliable power electronics technologies operating at high temperatures for automotive, aeronautic, and energy applications

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Bakri, Zohra. "Contribution a l'etude du sechage par rayonnement infrarouge d'un film de peinture sur un substrat plat en verre". Paris, ENMP, 1988. http://www.theses.fr/1988ENMP0081.

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On determine la composition, la densite, les proprietes thermodynamiques (pression de saturation en fonction de la temperature, coefficient de diffusion, chaleur latente de vaporisation) et les proprietes radiatives de la peinture (spectre d'absorption, spectre de reflexion diffuse, coefficient d'emissivite globale). On etablit une correlation donnant la quantite de solvant a evaporer en fonction de la temperature du substrat. Par ailleurs, l'evolution des profils experimentaux de temperature a ete obtenue par resolution numerique des equations de transfert de chaleur, sous l'hypothese que, pour ce produit quasi homogene, la puissance d'evaporation est infime. Enfin, dans une approche simplifiee, on propose une equation permettant de decrire les profils de perte de masse en fonction de la temperature du substrat

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Chater, Rabah. "Etude des antimonites MeSb 2 O 4 à basse température : évolution structurale, thermodynamique, propriétés élastiques et magnétiques anisotropes ; modélisation". Paris 6, 1986. http://www.theses.fr/1986PA066219.

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Etude par diffraction des RX et de neutrons, spectroscopie Raman et IR, chaleur massique, susceptibilité magnétique des antimonites (MNNifezn)sb2o4. Interprétation quantitative des anomalies de dilatation liées à Tltn dans le cas des composés de Ma et Fe. Définition d'un champ de force cohérent avec un potentiel de paires simplifié.

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Barj, Mohamed. "Etude de la structure statique et dynamique de quelques matériaux à mobilité ionique par spectroscopie de vibration et par diffusion de neutrons". Paris 13, 1987. http://www.theses.fr/1987PA132024.

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Etude des composés de la famille nasicon et de composés d'insertion type MPS(3), caracterisés par ir et raman. Les barrières de potentiel locales ont été calculées à partir des modes de phonons des ions conducteurs. Les amplitudes quadratiques spéctroscopiques ont été calculées dans les composés MPS(3) purs. Dans le cas des composés nasicon, on a relié la conductivité élèctrique et le désordre statique. Présentation de résultats de chaleur massique et de calculs d'énergie réticulaire à partir de potentiels atome-atomes. Mise en evidence d'une importante diffusion magnétique des ions Cr(3+) dans Na(3)Cr(2)P(2)O(12)

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Kumar, Navneet. "Evaporation of Water from Soil-like, Leaf-like Surfaces and Unconventional Porous Media". Thesis, 2016. http://etd.iisc.ac.in/handle/2005/4201.

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Evaporation is one of the inherent processes of our planet earth as an ecosystem. Water bodies, earth’s surface and vegetation all contribute significantly towards the total evaporation which eventually leads to the formation of clouds. The physical processes governing the evaporation from these surfaces differ significantly and thus needs to be studied individually. The factors which affect the total evaporation (evaporation & transpiration) are the surface temperature, ambient temperature, relative humidity, external wind speed, pressure, surface area and geometry. The present investigation deals with evaporation from three different surfaces: open water bodies, soil-like surfaces, and leaf-like surfaces. A ceramic infrared heater (2kW, 230V) has been used as the heater, in order to mimic the natural process, in all the experiments which were conducted in quiescent atmosphere i.e. without any external wind. The present work has been broadly categorized into two parts: - (a) evaporation from bare water surface, and (b) evaporation from a porous media. In part (a), we present experimental results on the evaporation from a bare water surface heated either from above using the infrared radiations or from below using heater immersed in the water. Heating from below leads to unstable stratification while infrared heating from above leads to stable stratification. The effect of water-side convection on the evaporation from a bare water surface has been investigated and all the experimental results have been combined to obtain a power law relation between Sherwood number (Sh) and Rayleigh number (Ra). Part (b) of the thesis has been further split into three major categories: - (1) evaporation from spheres based conventional porous media; (2) evaporation from novel porous media; and (3) evaporation from leaf-like surfaces. Mono-disperse spheres-based (non-hygroscopic) conventional porous media are used to mimic the natural soils. Glass beads (0.10-0.16 mm to 2.5-3.0 mm diameter), Stainless steel balls (1 mm diameter), sieved natural sand (0.3-0.5 mm diameter) and hydrophobic Ball Grid Array balls (0.30; 0.50; 0.76 mm diameter) have been used to create the conventional porous media. The range of Bond number (Bo) spanned in the present investigation is 2.2 ∗ 10−4 − 1.2 ∗ 10−1 based on the spheres dimensions. The experiments were conducted either in a cylindrical vessel (63 mm diameter and 90 mm height) or in rectangular acrylic boxes having dimensions similar to that of the cylindrical vessel. The heat flux received by the top surface of the porous media in majority of the experiments was 1000W/m2 which is close to the average annual solar insolation on the earths’ surface. The evaporation from these soil-type surfaces was found to undergo different and distinct stages. In the 1st stage of evaporation, commonly known as the constant rate period (CRP) regime, where the water in a confined 3D porous media remains on the surface and a high evaporation rate is observed. Surface tension-driven formations of capillary film(s) which rise to the surface are seen during CRP. The strength of the capillary has been defined in terms of a characteristic length called the capillary break-up length. In the 2nd stage of evaporation often called a falling rate period (FRP) regime, the capillary film which was supplying water to the top surface of the porous media breaks-up. The break-up, also termed as the transition regime, leads to receding liquid-vapour menisci and heat is conducted through the top dried layer to the water below where evaporation takes place the evaporation rate drops. Along with the wetting properties, the spheres size has been found to effect capillary break-up length and hence the duration of the stages of evaporation drastically. Surface images captured using a thermal camera clearly showed the presence of water till the capillary break-up length. The capillary break-up length was also found to be affected significantly by the heat flux or in other sense we can say that the evaporation rate in CRP regime is critical in deciding its duration in a spheres-based conventional porous media. In the present investigation heat flux ranged from 250-2000W/m2. Visualization has been carried out using a solution of de-ionized water and fluorescein dye. The colour contrast property (orange if dry and green in the solution form) of the fluorescein particles has been used to observe the evaporation sites in the porous media and to differentiate between the 1st and 2nd stage of evaporation. Apart from the experimental findings of single stack of mono-disperse spheres, multiple layering have also been investigated. The presence of complicated network of textural layering in the earth’s surface is a well-known fact. Along with the preferential evaporation, evaporation enhancement & suppression are reported in the experiments with texturally layered porous media independent of the orientation viz. vertical or horizontal layering. The stacking positions are also found to be critical in determining the overall evaporation characteristics. The geometry of a pore between three spheres in mutual contact is complicated. A simpler geometry for a pore could be that between two rods/plates in contact or three rods in mutual contact or stacks of either of these two. We call these types of porous media as “Novel porous media” as they possess many unique features not seen in a conventional porous media consisting of spheres. For this class of experiments the materials used to create the novel porous media were: Glass rods (2 & 3 mm diameter and 75 mm length), Glass capillaries (1.1/1.5 mm and 75 mm length), Faber-Castell pencil leads (0.7 mm diameter and 75 mm length), Glass plates (cross sectional dimension of 42 mm x 102 mm and thickness of 1.85 mm) and Cover slips (cross sectional dimension of 22 mm x 60 mm and thickness of 0.130.16 mm). The evaporation characteristics of vertically stacked rod-based novel porous media was found to be dominated by the corner films present in the near-zero radii contacts. Unlike the conventional porous media, the capillary break-up in the vertically stacked rod-based novel porous media was found to be limited by the vertical extent of the rods and not on the rod diameter. Due to the same reason, capillary break-up of vertically stacked rod-based novel porous media was also found to be independent of the heat flux range investigated in the present work. The 2nd stage of evaporation in these types of novel porous media therefore does not hold the true meaning as it is not forced by the porous media. The effect of orientation has also been investigated and the surface roughness was found to affect the evaporation dynamics drastically in horizontally stacked rod-based novel porous media. However, it is the surface roughness which was found to be dominant in case of vertically stacked plate-based novel porous media. The average size of a stoma, tiny holes present on the leaves, is nearly 20μm and the population density in majority of the plants is close to 5% of the leaf area. However the higher transpiration rates (60-70 % compared to a bare water source) sustained by a plant has remained a mystery for the phytologists. To study this we mimic the leaf-type surfaces by manufacturing silicon wafers having through holes. The leaf-mimics had different hole-diameter but same open area. The leaf-mimic with the smallest hole-size was found to evaporate the most while with increasing the hole-size the evaporation was found to decrease. In all the types of the leaf-mimic the evaporation ratio (ratio of the evaporation rate from the leaf mimic to that of the evaporation rate of a bare water surface at the same surface temperature) was found to increase with decreasing heat fluxes. The 3D nature of diffusion near these tiny holes enhances the evaporative flux, owing to increase in the concentration gradient of water vapour, which explains the high evaporation rates observed in the present work.

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SINGH, AJENDRA. "SOME STUDIES ON ARTIFICIAL INTELLIGENCE BASED FRACTIONAL ORDER PID CONTROLLER". Thesis, 2023. http://dspace.dtu.ac.in:8080/jspui/handle/repository/20133.

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Process control in industry is improving gradually with the innovations and implementation of new technology. Different control techniques are being used for process control. Proportional Integral and Derivative (PID) controller is employed in every facet of industrial automation. In any of control application, controller design is the most important part. There are different types of controller architectures available in control literature. The applications of PID controller span from small industries to high technology industries. Designing a PID controller to meet gain and phase margin specifications is a well-known design technique. If the gain and phase margin are not specified carefully, then the design may not be optimum in the sense that a large phase margin (more robust) that could give better performance. This research outlines the development and design of an infrared radiation heating profile controller. An attempt has been made to theoretically analyze the system, design of the Controller, their simulation, and real-time implementation of an infrared ceramic heating profile controller. The Controller has been subjected to comparative testing with a proportional control model to observe its performance and validate its effectiveness. PID controllers of this nature that are commercially available either lack the functionality of this unit or are too expensive to implement for research purposes. This unit has been designed with cost-effectiveness in mind but still meets the standards required for an industrial controller. Heating profiles are necessary and useful tools for the proper processing of a host of materials. The Controller developed in this research is able to meet a level of a fair degree of accuracy and track a heating profile. The results confirm that this programmable control model will be advantageous and a valuable tool in temperature regulation. This means that intensive studies into the effects of infrared radiation on materials are now feasible. Research of this nature could possibly expand the application of infrared as a heating mechanism. Although tests were conducted on this Controller, they are not meant to serve as an exhaustive analysis. The conclusions of these simulations do reveal the benefit of such a v controller. More rigorous investigation is suggested as a subject for further study. System identification of this nonlinear process is done using black box model, which is identified to be nonlinear and approximated to be a First Order plus Dead Time (FOPDT) model. In order to obtain an accurate mathematical expression of the IR heater used in this research, a step response test of the IR heater has been completed. This method of testing has been done in accordance with the Ziegler-Nichols, Astrom Hügglund, and Cohen-Coon methods. Simulation of the obtained transfer function, using Mat Lab software, showed good agreement. Although the transfer function represented a first-order model with transportation lag, the simulated results reflected an acceptable accuracy. An exhaustive study has been done on different PID controller tuning techniques. The PID controller of the model has been designed using the classical method, and the results have been analyzed. A compromise has been made between robustness and tracking performance of the system in the presence of time delay. The results of the simulation indicate the validity of the study. Integer order PID controller (IOPID) based on Bode plot and Nyquist plot has been designed. The results illustrate that the IOPID controllers have the capability of minimizing the control objectives better than the previously designed controllers (Ziegler-Nichols, Astrom-Hügglund, and Cohen-Coon method-based Controller).With the change in temperature occurs, the oscillations of the controlled system outputs are eliminated and the output steady state errors become very small. The results demonstrate that the IOPID controller is stable and it suppresses the cost function (Maximum overshoot, Rise Time, Settling time and Peak time) even in case of significant disturbances. IOPID controller has also been designed using Bode plot and Nyquist plot for high gain system. The results have shown that the responses of Ceramic IR heater temperature profile have been reduced to very small value and prove that the IOPID controller is still stable and it suppresses the cost function even if significant disturbances have occurred. Fuzzy Logic controller-based model reference has been designed. Its implementation indicates that the proposed Controller suppresses the output of the controlled system. The results illustrate that the proposed Controller only slightly vi improves the performance of the cost function. The various AI techniques (GA) and Soft Computing (bio inspired) based algorithm (BFO, ACO) for PID controller offers several advantages. These methods can be used for higher order process models in complex problems. Approximations that are typical to classical tuning rules are not needed. Compared to conventionally tuned system, GA, PSO, BFO and ACO tuned system provides good steady state response and performance indices. The genetic approaches can achieve better temperature control with smaller settling time, overshoot and undershoot, and zero steady error. The control signal changes more frequently and with larger magnitude as the genetic algorithms are stochastic in nature. The PSO has an additional unique advantage that it adapts any change in system conditions, and obtains different system dynamics accurately in a short time period. It is a random search method but if combined with an artificial intelligence features, it tracks required system dynamics accurately in short time (small number of iterations). The BFO based Controller has the advantage of a better closed loop time constant, which enables the Controller to act faster with a balanced overshoot and settling time. The response of the conventional Controller is more sluggish than the BFO based Controller. Compared to conventionally tuned system, BFO tuned system has better steady state response and performance indices. Ant- Colony algorithm (ACO) has no special requirements on the characteristics of optimal designing problems, which has a fairly good universal adaptability and a reliable operation of program with ability of global convergence. Simulation results show the controlled system has satisfactory response and the proposed method has an effective tuning strategy. ACO shows better performance for PID controller parameter tuning of the considered control system. The simulation results show that the proposed method achieve minimum tracking error and estimate the parameter values with high accuracy. The work presents tuning method for fractional order proportional Integral and derivative controllers (FOPID) for the first order plus time delay (FOPTD) class of systems based on gain and phase margin. Techniques such as fractional order PID controller design and the results of their application to real-world system vii have been presented. A comparative study has been done using different control techniques to analyze the performance of different controllers. First, the conventional PID controller is implemented as primary Controller. The performance of PID, IOPID, Fuzzy Logic Controller, and Artificial Intelligence based PID, Bio inspired based PID controller and FOPID controllers have been examined. It has been concluded that the overall performance of the FOPID-based Controller is better than other controllers. In real-time implementation, the performance of the process control includes the time required by the heater to be settled on the initial set-up temperature. The rising of temperature is slow due to the resistance heating element used in ceramic infrared heaters. So the settling time is very high. The results obtained by simulation and real-time implementation with fractional order PID controller show overall better performance( rise time , settling time, peak time and peak overshoot) in comparison with other designed and implemented Controllers embedded with ceramic infrared systems. Further stability problems of fractional order system with leakage delay and distributed delay with hybrid feedback controller have been solved (with examples) using the Mittag-Leffler function and Lyapunov direct method and proved Global Mittag-Leffler stability of fractional order system of the proposed model which implies faster convergence rate of the network model which represents the stability of the system. This work performs a small-scale test measuring controller performance so that it serves as a platform for future research efforts leading to the real-life implementation of a Ceramic Infrared Heater Temperature control system.

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Huang, Jun Jie, i 黃俊傑. "IR heated roller embossing of dual-sided microstructures onto plastic plates". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/94587121466370820132.

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碩士
長庚大學
機械工程學系
98
This paper reports a novel infrared assisted roller embossing technique for the rapid fabrication of polymeric diffusion films with dual-sided microstructures. A roll-to-roll embossing facility with infrared heating has been designed, constructed and tested in our laboratory. Metallic rollers bearing microstructures are fabricated using a tungsten carbide turning machine. They were then used to replicate the microstructure onto 0.5 mm thick PC and PET films in the experiments. During roller embossing, the rollers are heated by the infrared energy to melt the thermoplastic at the roller/film interface and thereby to replicate the microstructure. Under the proper processing conditions, plastic films with 90 degree cross-angle dual-sided microstructures can be successfully fabricated. The experimental results in this study suggest that infrared assisted roller embossing provides an effective way of fabricating microstructures onto plastic substrates. This would provide significant advantages in terms of a shorter cycle time as well as improved product quality.

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40

"Nutritional and Microstructural Responses in Cereal Grains to Heat-Related Processing Methods". Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-10-2285.

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Cereal grains share many common traits, but they also have different internal structures, nutrient values, degradation kinetics and digestion features. Heat treatments are commonly used in the feed industry. It is known that heat is able to change the nutrient values of the feed but the effect could be equivocal. In order to understand the effects of heat processing on internal structure and nutrient availability of cereal grains, two batches of wheat, triticale and corn were divided into three groups (control/raw (unheated), dry heating and moist heating) and processed at 121 °C for 80 min. Basic chemical analysis and in situ, in vitro assays were conducted and CNCPS, DVE/OEB and NRC-2001 models were used to determine the nutrient availability of the grains. In addition, two mid-IR molecular spectroscopy techniques (Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and Synchrotron Radiation Infrared Microspectroscopy (SR-IMS)) were used to gain an insight into the heat-induced changes in the functional groups. Significant (P<0.05) differences were found between the cereal grains in their nutritional availabilities, including their chemical characteristics, protein and carbohydrate fractions, energy values, the ruminal degradation kinetics, hourly effective rumen degradation ratios, potential N-to-energy synchronization, and intestinal digestion of cereal grains. Compared to dry heating, moist heating had more impact on altering the nutrient profiles and showed the potential to increase the nutrient availability of wheat and triticale for dairy cattle. Significant differences (P<0.01) were detected between different feeds and heat treatment groups by using the ATR-FTIR technique. Results were found in consistency with the conventional chemical and animal studies mentioned above despite when using the SR-IMS technique. Significant (P<0.05) correlations were detected between some structure spectral characteristics and nutrient digestion traits. In conclusion, the moist heating had more profound impact than the dry heating in increasing nutrient supplies to ruminants in wheat and triticale. The heat-induced effects found in corn were less positive. The ATR-FTIR technique could detect the internal structural changes in cereal grains, while the sensitivity and accuracy of the SR-IMS technique were not proved in this study.

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周志豪. "Thermo-dynamic diagnostics in three-intersection flow network heat sink using IR thermometry". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/51552059475629481389.

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碩士
南台科技大學
機械工程系
91
A multiple-intersection flow network is common in biological and industrial systems such as the human vascular system, the internal coolant passage of turbine blade inside gas turbine engine, the liquid cooling channel inside electronic modules. The present study investigates experimentally thermal-hydraulic performance of single-phase water flow in a multiple-intersection heat sink. The effects of different geometrical parameters are investigated at various air inlet frontal velocities. This main focus is to find the criteria of generating the Coanda effect due to vary the geometrical parameters and Reynolds number. Results will also express in terms of the heat transfer and friction factors and their ratio, call the goodness factor. In addition, an infrared thermovision system is used to map the transient temperature change on the base of the multiple-intersection heat sink under constant heat flux. The local heat transfer coefficient can be determined by using the temperature map. The main effort of the present study is attempting to understand the detailed heat transfer characteristics caused by the complex flow patterns measured by Particle Image Velocimetry.

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Freund, Sebastian [Verfasser]. "Local heat transfer coefficients measured with temperature oscillation IR thermography / vorgelegt von Sebastian Freund". 2008. http://d-nb.info/988042142/34.

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"Numerical Modeling and Experimental Studies on the Hydrodynamics and Heat Transfer of Silica Glass Particles". Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.57399.

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abstract: Granular material can be found in many industries and undergo process steps like drying, transportation, coating, chemical, and physical conversions. Understanding and optimizing such processes can save energy as well as material costs, leading to improved products. Silica beads are one such granular material encountered in many industries as a catalyst support material. The present research aims to obtain a fundamental understanding of the hydrodynamics and heat transfer mechanisms in silica beads. Studies are carried out using a hopper discharge bin and a rotary drum, which are some of the most common process equipment found in various industries. Two types of micro-glass beads with distinct size distributions are used to fill the hopper in two possible packing arrangements with varying mass ratios. For the well-mixed configuration, the fine particles clustered at the hopper bottom towards the end of the discharge. For the layered configuration, the coarse particles packed at the hopper bottom discharge first, opening a channel for the fine particles on the top. Also, parameters such as wall roughness (WR) and particle roughness (PR) are studied by etching the particles. The discharge rate is found to increase with WR, and found to be proportional to (Root mean square of PR)^(-0.58). Furthermore, the drum is used to study the conduction and convection heat transfer behavior of the particle bed with varying process conditions. A new non-invasive temperature measurement technique is developed using infrared thermography, which replaced the traditional thermocouples, to record the temperatures of the particles and the drum wall. This setup is used to understand the flow regimes of the particle bed inside the drum and the heat transfer mechanisms with varying process conditions. The conduction heat transfer rate is found to increase with decreasing particle size, decreasing fill level, and increasing rotation speed. The convection heat transfer rate increased with increasing fill level and decreasing particle size, and rotation speed had no significant effect. Due to the complexities in these systems, it is not always possible to conduct experiments, therefore, heat transfer models in Discrete Element Method codes (MFIX-DEM: open-source code, and EDEM: commercial code) are adopted, validated, and the effects of model parameters are studied using these codes.
Dissertation/Thesis
Doctoral Dissertation Chemical Engineering 2020

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44

Yen, Liang-I., i 顏良益. "Experimental Investigation of Thermal Performance for Plate-Fin Heat Sink with Piezoelectric Fan by Using IR Thermovision". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/48827583662237137272.

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碩士
國立高雄應用科技大學
模具工程系
99
The features of electronic component are “light”, “thin”, “short”, and “small” is the global trend. That is, electronic components are designed toward miniaturization such as laptop, smart phones. Due to the characteristics of piezoelectric fan are small size, ultralight, simple structure, and sensitive response. It is suitable for cooling application in miniaturization electronic components. The purpose of this study is to explore the heat dissipation efficiency of piezoelectric fan with different type heat sinks by changing the piezoelectric fan height which is relative to four different heat sinks. This study use flow visualization technique (Middle wave infrared), driven by 110V, 60Hz and fix the amplitude range of piezoelectric fan and distance (0.5 mm,1mm,2mm,3mm,4mm,5mm and 7mm) between blade tip and fin side. To examine the piezoelectric fan flow phenomena with single fin, end-slotting plate-fin heat sink, middle-end slotting plate-fin heat sink and center-slotting and end-slotting plate-fin heat sink. From the fin temperature gradient of infrared image, the empirical results showed the change of slope on the isothermal under the free convection and jet-like flow forced convection. The distance between blade tip and heat sink is getting closer, and the thermal resistance is less. Oppositely, with the distance increased, the thermal resistance is getting upward. Compare to the thermal resistance of non-piezoelectric fan and piezoelectric fan with single fin, it had been found the piezoelectric fan which used in this research can increases the thermal resistance up to four times, and it can be three to five times when using multi-fin. Besides, as piezoelectric fan works with multi-fin and set at the middle, the amplitude covers the most part of heat sink. That could push the air into the heat sink effectively for cooling. Moreover, comparing to the thermal resistances, it found the middle-end slotting plate-fin heat sink acquire the lower thermal resistance.

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(9760715), Nicholas Toan-Nang Vu. "High-Speed Flow Visualization and IR Imaging of Pool Boiling on Surfaces Having Differing Dynamic Wettabilities". Thesis, 2020.

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Boiling is used in a wide variety of industries, including electronics cooling, distillation, and power generation. Fundamental studies on the boiling process are needed for effective implementation. Key performance characteristics of boiling are the heat transfer coefficient, which determines the amount of heat flux that can be dissipated for a given superheat, and critical heat flux(CHF), the failure point that occurs when vapor blankets the surface. The wettability of a surface is one of the key parameters that affects boiling behavior. Wetting surfaces(e.g., hydrophilic surfaces), typically characterized by a static contact angle below 90°,have better critical heat flux due to effective rewetting, but compromised heat transfer coefficients due to increased waiting times between nucleation of each bubble. Meanwhile, nonwetting surfaces (e.g., hydrophobic surfaces), characterized by static contact angles greater than 90°, have better heat transfer coefficients due to improved nucleation characteristic, but reach critical heat flux early due to surface dry out. However, recent studies have shown that the static contact angle alone offers and incomplete, and sometimes inaccurate, description of this behavior, which is instead governed entirely by the dynamic wettability. Specifically, the receding contact angle impacts the size and contact area of bubbles forming on a surface during boiling, while the advancing contact angle determines how the bubble departs. With this more complete set of wettability descriptors, three characteristic wetting regimes define the boiling behavior: hygrophilic surfaces having advancing and receding contact angles both under 90°; hygrophobic surfaces having both these dynamic contact angles over 90°;and ambiphilic surfaces having a receding contact angle less than 90°, but an advancing contact angle greater than 90°.The goal of this thesis is to experimentally characterize and compare the behavior of boiling surfaces in each of these regimes, observe the contact line behavior, and explain the mechanisms for their differences in performance.

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Mani, Preeti. "Local heat transfer rate and bubble dynamics during jet impingement boiling". Thesis, 2012. http://hdl.handle.net/1957/35039.

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Characterization of local boiling trends, in addition to the typically reported area-averaged trends, is essential for the robust design and implementation of phase change technologies to sensitive heat transfer applications such as electronics cooling. Obtaining the values of heat fluxes corresponding to locally varying surface temperatures has been a challenge limiting most investigations to area-averaged results. This thesis illustrates the importance of a spatially local heat transfer analysis during boiling. Pool and submerged jet impingement boiling scenarios on a silicon surface are considered at the macroscale (27.5 mm heater with multiple nucleation sites) and microscale (1000 ��m heater for isolated bubble generation), by the use of two thin film serpentine heater geometries. The macroscale heater highlights the effect of spatial variations in imposed heat flux on boiling heat transfer with a circumferentially uniform but radially non-uniform heat flux distribution. The microscale heater simulates a local hot-spot for spot cooling on an electronic device. Spatial variation in boiling heat transfer and bubble dynamics with and without a jet flow are documented using thin film voltage sensors along with qualitative and quantitative high speed imaging and infra-red thermography. Unique to this study is the documentation of local boiling curves for different radial locations on the heat transfer surface and their comparison with the corresponding area-averaged representations. It is shown here that sectionally averaged representations of boiling curves over regions of like-imposed heat flux can substantially simplify the interpretation of data while retaining important information of the local variations in heat transfer. The radial influence of the convective jet flow on the bubble dynamics and boiling heat transfer is assessed for a single circular submerged jet configuration. Varied parameters include jet exit Reynolds numbers, nozzle geometry, test fluid (deionized water and FC-72), fluid subcooling and the supplied heat flux. Distinct modifications of the surface temperature distribution imposed by the impinging jet flow are highlighted by comparing radial temperature profiles during pool and jet impingement boiling. It is demonstrated that in contrast with pool boiling, thermal overshoots during jet impingement boiling for a highly wetting fluid like FC-72 are highest in regions farthest from the impingement point. The effect of jet inertia on bubble departure characteristics are compared with pool boiling under subcooled conditions for FC-72. Qualitative high speed visualization indicates the presence of two modes of bubble generation during jet impingement boiling (a) bubble departure from the surface and (b) bubble separation from the source resulting in sliding bubbles over the surface. The effect of jet flow on bubble entrainment is depicted. Quantitative results indicate that in general departure diameters for pool and jet impingement boiling increase and plateau at a maximum value with increasing power input while no notable trends were observed in the corresponding departure frequencies. The largest departure diameters for jet impingement boiling at fixed fluid subcoolings of 10��C and 20��C were found to be smaller than that for the corresponding pool boiling test by a factor of 1.6 and 2.3, respectively.
Graduation date: 2013

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Menezes, Dânia Catarina Costa Alpoim. "Desenvolvimento de métodos expeditos para a caraterização das propriedades finais de diferentes substratos". Master's thesis, 2017. http://hdl.handle.net/1822/50039.

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Dissertação de mestrado em Técnicas de Caraterização e Análise Química
As propriedades finais e o desempenho dos materiais são caraterísticas apreciadas por uma sociedade cada vez mais preocupada com o conforto e com fatores de segurança dos materiais com os quais contactam no seu dia-a-dia. Assim, este estudo teve como objetivo o desenvolvimento de métodos expeditos que permitissem avaliar o desempenho de diferentes materiais em termos de sensação térmico ao toque e de retardância à chama. No que respeita à perceção térmica ao toque, à temperatura ambiente, foram efetuados estudos qualitativos com recurso a voluntários. Com o objetivo de desenvolver uma escala de avaliação da perceção térmica, tomou-se como ponto de partida a validação de uma ferramenta de análise sensorial. Foram identificados pontos de melhoria e o quadro desenvolvido assumiu novos valores de intensidade de perceção térmica para um conjunto mais alargado de materiais de referência. A efusividade térmica é a propriedade que mais contribui para a diferenciação dos materiais ao nível da perceção térmica. Neste estudo, estabeleceu-se uma relação logarítmica entre os valores de intensidade térmica da escala de perceção e os valores de efusividade térmica dos materiais. Através desta relação, foram calculados os valores teóricos de intensidade térmica para amostras de ABS e PP, a partir dos seus valores de efusividade térmica. Os valores calculados foram semelhantes aos obtidos na avaliação com base no quadro desenvolvido, evidenciando a relação logarítmica entre a efusividade térmica e a perceção da temperatura ao toque dos materiais. Os estudos de desempenho térmico de amostras poliméricas e cerâmicas com propriedades de reflexão no IV revelaram que estas transmitem uma sensação menos quente ao toque e sofrem um aumento menor de temperatura do que os respetivos controlos, em situação de exposição IV e solar. Estes resultados estão relacionados com os valores elevados de refletância no IV e de baixa emissividade observados para estas amostras. Por fim, na avaliação do desempenho da cortiça em termos de retardância à chama, não se conseguiu distinguir o comportamento ao fogo entre as amostras aditivadas e os seus controlos, uma vez que o método implementado permite apenas atribuir classe E. Para classificações superiores, teria que se efetuar ensaios que requerem equipamento específico, tendo sido a principal limitação para a implementação de outros métodos de ensaio.
The final properties and performance of the materials are characteristics appreciated by a society increasingly concerned with comfort and adequate safety factors of the materials with which they contact in their daily life. The aim of this study was the development of expeditious methods to evaluate the performance of materials in terms of thermal comfort and flame retardancy. Regarding the temperature perception, at room temperature, qualitative studies were carried out with the use of volunteers. With the objective of developing a scale of evaluation of the thermal perception to the touch, the validation of a sensorial analysis tool was taken as starting point. Improvement points were identified and the developed framework assumed new values of thermal perception intensities for a broader set of reference materials. The thermal effusivity is the property that contributes most to the differentiation of the materials with respect to thermal perception. In this study, a logarithmic relation was established between the thermal intensity values of the perception scale and the thermal effusivity values of the materials. Through this logarithmic relation, the theoretical values of thermal perception intensity for the ABS and PP samples were calculated from their thermal effusivity values. The calculated values were similar to those obtained when the evaluation was performed with the developed framework, evidencing the logarithmic relation between the thermal effusivity and the temperature perception to the touch of the materials. The thermal performance studies of polymeric and ceramic samples with IR reflective properties revealed that the samples transmit a milder sensation to the touch and suffer a lower temperature increase than the respective controls, in situation of IR and solar exposure. These results are related to the high values of reflectance in the IR and low emissivity observed for these samples. Finally, in the evaluation of the cork performance in terms of flame retardancy, it was not possible to distinguish the fire behavior between the additivated samples and their controls, since the implemented method only allows to assign the class E. For higher classifications, another tests, which require specific equipment, would have to be carried out, and this has been the main limitation for the implementation of other testing methods.

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