Dissertations / Theses on the topic 'HFHC'
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Fan, Haibo. "HfC structural foams synthesized from polymer precursors." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Dissertation/FAN_HAIBO_30.pdf.
Full textWheeler, Mark R. "The adsorption of HFC-134a onto zeolite Na-13X." Thesis, Brunel University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307487.
Full textNeilson, Martin M. "The bulk and surface properties of HFC replacement refrigerants." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312801.
Full textАрсеньєв, В`ячеслав Михайлович, Вячеслав Михайлович Арсеньев, Viacheslav Mykhailovych Arseniev, Валерій Миколайович Марченко, Валерий Николаевич Марченко, Valerii Mykolaiovych Marchenko, Михайло Ігорович Проценко, Михаил Игоревич Проценко, and Mykhailo Ihorovych Protsenko. "Энергоэффективность струйного понижающего термотрансформатора на рабочих веществах HFC - типа." Thesis, Изд-во СумГУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/6713.
Full textNarasimhan, Anirudhan. "Commercialization of HFAC Electronic Nerve Block Technology to Treat Chronic Post Surgical Pain." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1290641992.
Full textYan, Yu. "Performance optimisation of HFC refrigerants by experimental and mathematical methods." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248796.
Full textBoisselier, Guilhaume. "Dépôt chimique en phase vapeur de carbures de chrome, de silicium et d'hafnium assisté par injection liquide pulsée." Thesis, Toulouse, INPT, 2013. http://www.theses.fr/2013INPT0064/document.
Full textCeramic coatings are made from metalorganic precursors by a chemical vapour deposition process assisted by pulsed liquid injection (DLICVD). Chromium carbide (CrCx) films are grown in a tubular hot wall reactor from a solution of bis(benzene)chromium in toluene under partial pressure of nitrogen at 475 °C (total pressure set at 50 Torr). Bonding layers are useful on metallic components, such as steels and alloys, with non-oxide ceramic films such as CrCx, to that purpose metallic chromium (Cr) and mixed carbides Cr-Si-C have been made by DLICVD. Furthermore, adding a chlorinated or sulfur based additive (e.g. hexachlorobenzene or thiophenol) in the BBC/toluene solution allows depositing metallic chromium (Cr) at 475 °C. Moreover, using a precursor containing Si and Cr as tetrakis(trimethylsilylmethyl)-chromium in toluene leads to the deposition of Cr-Si-C mixed carbide. Silicon carbide films are made from two precursors (1,3-disilabutane and polysilylethylene) that have been injected either pure or diluted in toluene. A temperature range of 700 to 800 °C has been used under a partial pressure of nitrogen (total pressure of 50 Torr). SiC films are amorphous and contain a small quantity of hydrogen (hydrogen comes from precursor pyrolysis mechanism): a-SiC:H. Films are stoichiometric when pure precursors are injected, and quasi stoichiometric when precursors are diluted in toluene. As deposited coatings are amorphous and become nanocristalline (cubic SiC structure) after annealing at 1000 °C under vacuum. The influences of the solvent (toluene) on the composition, morphology and growth rate are discussed as a function of the chemical system and experimental conditions, in particular reactor gradient conditions such as temperature and precursors concentration in gas phase. Hafnium carbide films are also made using a solution of bis(cyclopentadiényl)diméthyl hafnium in toluene by the same process. Temperature is set to 750 °C and hydrogen partial pressure has been shown useful (total pressure of 50 Torr, 423 sccm of N2 and 77 sccm of H2). As-deposited films are C-rich HfCx and quasi amorphous. They become nanocristalline after annealing at 1000 °C under vacuum. Finally, ceramics multilayer HfC/SiC coatings were deposited by DLICVD at 750 °C under a partial pressure of a mixture of N2/H2. The process allows a good control of the multilayer nanostructure. Thermal stability and high temperature oxidation preliminary tests on SiC and HfC/SiC films are discussed
Loan, Nguyen Kim, and n/a. "Listening comprehension tests for intermediate students at Hanoi Foreign Languages College." University of Canberra. Education, 1989. http://erl.canberra.edu.au./public/adt-AUC20060818.141820.
Full textBruna, Paez Eduardo Andrés. "Modelo preventivo de morosidad temprana de clientes HFC mediante clasificación bayesiana." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/112522.
Full textEste proyecto, formó parte del plan de mitigación de clientes morosos implementado por una empresa de telecomunicaciones en el año 2009, dónde una de las líneas de acción estaba enfocada en disminuir la morosidad de los nuevos clientes en su primera factura. Se propuso un modelo que clasifique a los nuevos clientes en pagadores y no pagadores, permitiendo con ello, reorientar recursos y realizar acciones preventivas de morosidad de manera más focalizada y efectiva, las cuales estaban siendo hasta ese momento aplicadas al universo total de nuevos clientes. El éxito de este proyecto requería el compromiso del área de cobranzas, usuaria del modelo, por esto, la elección del modelo consideró aspectos tanto teóricos como prácticos. La simpleza y la fácil ejecución del modelo, idealmente programable, eran variables deseables y decidoras del éxito de éste. Se ejecutó basado en Clasificación Bayesiana por su forma simple de utilizar y presentar una confiabilidad aceptable [17]. Los métodos de inducción bayesiana han demostrado ser una clase de algoritmos tan competitivos como los métodos árboles de decisión y redes neuronales [29], que permiten implementar algoritmos en Wolfram Mathematica 6.0 cuyas sentencias de programación son muy similares al lenguaje C++, permitiendo su programación posterior. El modelo se confeccionó con 42.087 clientes, contratantes entre el 15 de julio y el 15 de octubre del 2009, de estos, 40.087 formaron la base de aprendizaje para calibrar y realizar los cálculos de probabilidades, y 2.000 como base de testing. Los clientes a clasificar en pagadores y no pagadores correspondieron a 9.328, quienes ingresaron a la empresa entre el 16 de Octubre y el 15 de Noviembre del 2009. En base a establecer una probabilidad a priori, se plantea en valores estimados de corte probabilístico basado en la experiencia o un método de clasificación [19], por una probabilidad de corte de 0,4 para clasificar a un cliente pagador por la necesidad que enfrenta la empresa de mejorar el % de clientes morosos en su primera boleta y a la vez reducir los costos actuales involucrados en la cobranza. El modelo clasificó a 2.910 clientes como no pagadores, 2.179 de ellos efectivamente no cancelaron su boleta al vencimiento (75%). Este resultado es compatible con el esperado en el análisis teórico, debido a la eficiencia de los estimadores estimados, como también, el tamaño de los set de datos empleados que en forma teórica respalda los resultados obtenidos con un 80% de confiabilidad. Como trabajo futuro, resulta interesante evaluar el aporte del modelo en la reducción real del porcentaje de clientes morosos al permitir reorientar recursos y focalizarse en ciertos clientes, como a su vez, actualizar la base de aprendizaje de tal forma ir considerando la actualidad al modelo.
Chen, De-Kang. "Flashing flow of refrigerant HFC-134a through a diabatic capillary tube." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25924.pdf.
Full textScholz, B. [Verfasser]. "Untersuchung an TaC-HfC-Hartstoffen mit und ohne Bindemetall / B. Scholz." Karlsruhe : KIT-Bibliothek, 2010. http://d-nb.info/1187252808/34.
Full textTumbalobos, Cubas Brenda Jackeline. "Estudio del diseño de servicio IPTV con tecnología HFC y FTTH." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2016. http://tesis.pucp.edu.pe/repositorio/handle/123456789/6860.
Full textTesis
Reilly, Michael Anthony. "Characterisation of HFC-134a by gas chromatography-mass spectrometry and chemometrics." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/14268.
Full textDung, Tran BA Viet, and n/a. "Teaching listening skills to students of commerce at Hanoi Foreign Trade College." University of Canberra. Education, 1989. http://erl.canberra.edu.au./public/adt-AUC20060706.122222.
Full textAlalwan, Mahmood A. "In Vitro Evaluation oF Aerosol Drug Delivery With And Without High Flow Nasal Cannula Using Pressurized Metered Dose Inhaler And Jet Nebulizer in Pediatrics." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/rt_theses/14.
Full textGrénar, Milan. "Implementace pokročilé filtrace s klasifikací paketů pro bezdrátové sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218953.
Full textWolff, Rojas Patricio. "Diseño e Implementación de un Curso de Servicios Sobre Redes HFC de Nueva Generación." Tesis, Universidad de Chile, 2009. http://repositorio.uchile.cl/handle/2250/103626.
Full textYu, Yingzhong. "Approche générique des modes d'émissions de HFC-134a des systèmes de climatisation automobile." Phd thesis, École Nationale Supérieure des Mines de Paris, 2008. http://pastel.archives-ouvertes.fr/pastel-00004889.
Full textMoosavi, Atena, Sven Osterland, Dominik Krahl, Lutz Müller, and Jürgen Weber. "Numerical prediction and experimental investigation of cavitation erosion of hydraulic components using hfc." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71096.
Full textFouley, Aurélie. "Evaluation prédictive de la toxicité et de l'écotoxicité des principaux HCFC et HFC." Caen, 1996. http://www.theses.fr/1996CAEN4055.
Full textRemes, J. (Janne). "The development of laser chemical vapor deposition and focused ion beam methods for prototype integrated circuit modification." Doctoral thesis, University of Oulu, 2006. http://urn.fi/urn:isbn:9514281403.
Full textPadilla, Gomez Miguel David. "Experimental study of third (HFC) and fourth generation (HFO) refrigerants during flow boiling in singularities." Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00715788.
Full textMattarredona, Edgar Antonio Costa. "Dos parametros de degradação do canal de retorno em redes hibridas fibra/coaxial (HFC) interativas." [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261905.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-07-28T20:05:53Z (GMT). No. of bitstreams: 1 Mattarredona_EdgarAntonioCosta_M.pdf: 1277176 bytes, checksum: 86ae5ea6da667f07e5225456194a3d3e (MD5) Previous issue date: 2001
Mestrado
Yaddanapudi, Satvik Janardhan. "Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc822762/.
Full textGebru, Sofia. "Performance of uncooled 1.3 [mu]m FP and DFB lasers in hybrid fiber-coax (HFC) networks." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/45494.
Full textIn title, on t.p. of thesis and in exercises program, "[mu]" appears as the Greek lower-case letter.
Includes bibliographical references (leaf 95).
by Sofia Gebru.
M.Eng.
Palma, Ricardo Jorge da Silva. "Relatório de atividade profissional." Master's thesis, Escola Superior de Tecnologia do Instituto Politécnico de Setúbal, 2013. http://hdl.handle.net/10400.26/5389.
Full textNo âmbito da adequação dos ciclos de estudo da Escola Superior de Tecnologia de Setúbal ao designado Processo de Bolonha, pretendo com este ralatório, enquanto licenciado "pré-Bolonha", obter o grau de Mestre em Engenharia Eletrotécnica e de Computadores, com base nas competências adquiridas no decorrer do meu percurso profissional e aqui descritas. Concluo que as funções desempenhadas permitiram-me consolidar e expandir os conhecimentos adquiridos na Licenciatura em Engenharia Eletrotécnica e Computadores
Vall, Palomar Mònica. "Estudi dels mecanismes genètics i moleculars associats a les diferències fenotípiques observades en pacients amb hipomagnesèmia familiar amb hipercalciúria i nefrocalcinosi (HFHNC)." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/671335.
Full textLa hipomagnesemia familiar con hipercalciuria y nefrocalcinosis (HFHNC) es una tubulopatía minoritaria autosómica recesiva causada por mutaciones en los genes CLDN16 o CLDN19, que codifican para la claudina-16 y -19, respectivamente, expresadas en la porción gruesa del asa ascendente de Henle, e implicadas en el transporte iónico paracelular. Esta enfermedad se caracteriza por la pérdida urinaria de calcio y magnesio, nefrocalcinosis bilateral y progresión inexorable de la enfermedad renal crónica, que desencadena en fallo renal. Adicionalmente, la mayoría de pacientes con mutaciones en CLDN19 también desarrollan alteraciones oculares, ya que este se expresa en las células epiteliales de la retina. Existe una gran variabilidad fenotípica entre pacientes, incluso entre aquellos que comparten la mutación c.59G>A; p.G20D en CLDN19 (mutación Hispánica), y entre miembros de una misma familia. Este fenómeno sugiere que, más allá de la mutación causante de la enfermedad, posiblemente existen otros procesos moleculares que determinan la progresión clínica de los pacientes. Bajo esta hipótesis, este trabajo se ha focalizado en el estudio de los factores genéticos y epigenéticos que podrían modular la progresión de la enfermedad renal. Para ello, se han obtenido los datos clínicos, orina y sangre de 30 pacientes afectos de HFHNC y 6 individuos control de diferentes lugares de España, siendo estos la mayoría de pacientes diagnosticados de HFHNC en este territorio. El análisis de los datos clínicos permitió evaluar las diferencias en la evolución de la enfermedad renal en función del sexo y del genotipo, clasificar los pacientes según la pérdida anual de función renal (progresión renal rápida, moderada y lenta), identificar biomarcadores clínicos de pronóstico, y evidenciar la alta variabilidad fenotípica intrafamiliar. El estudio para la identificación de variantes génicas en homocigosis asociadas a los fenotipos más extremos (progresión renal rápida y lenta) se realizó con los datos obtenidos de la secuenciación masiva del exoma de los 30 pacientes de la cohorte. Con esta estrategia, se identificaron 45 variantes génicas. De entre estas, por la función fisiológica de los genes donde se localizan, destacan la rs11207827 (en el gen PATJ) y la rs1050171 (en el gen EGFR). Para determinar los factores epigenéticos implicados en la fisiopatología de la HFHNC y en su progresión, se utilizaron los urinary exosome-like vesicles (uEVs) como fuente no invasiva de información de procesos celulares renales. Mediante microarrays, se analizó el perfil de expresión de los miRNAs contenidos en los uEVs de los 20 pacientes que mantenían los riñones nativos funcionales, identificándose 24 miRNAs diferencialmente expresados en el total de pacientes respecto al grupo control, y 43 en el subconjunto de pacientes homocigotos para la mutación p.G20D en CLDN19. La comparación de pacientes de ambos sexos mostro únicamente la infraexpresión del miR-1915-5p en aquellos de sexo masculino. Finalmente, se identificaron 4 miRNAs diferencialmente expresados en los pacientes con progresión renal moderada, en comparación con el de progresión lenta, y 8 en el subgrupo de pacientes homocigotos para la mutación p.G20D en CLDN19. La biología de sistemas y el uso de redes neuronales de inteligencia artificial han permitido asociar los resultados obtenidos con procesos biológicos cruciales en la fisiopatología de la HFHNC, como la fibrosis renal y el transporte de calcio y magnesio, entre otros. Este trabajo ha permitido incrementar el conocimiento de la fisiopatología de la HFHNC y determinar factores clínicos, genéticos y epigenéticos implicados en la disfunción renal. Desde el punto de vista traslacional, se han identificado nuevos posibles biomarcadores pronósticos de la HFHNC, y dianas terapéuticas que podrían permitir modular la severidad de la enfermedad y, en el mejor de los casos, curarla.
Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a rare autosomal recessive tubulopathy caused by mutations in either CLDN16 or CLDN19 genes, which encode for claudin-16 and -19, respectively, expressed in the thick ascending loop of Henle, and involved in paracellular ion transport. This disease is characterized by urinary loss of calcium and magnesium, bilateral nephrocalcinosis, and inexorable progression of chronic renal disease leading to renal failure. Besides, most patients with CLDN19 mutations also develop ocular anomalies, as it is expressed in the retinal epithelial cells. There is great phenotypic variability among patients, even in those who share the c.59G>A; p.G20D mutation in CLDN19 (Hispanic mutation), and also among members of the same family. This phenomenon suggests that, beyond the mutation causing the disease, other molecular processes could determine the clinical progression of patients. Under this hypothesis, this work has focused on the study of genetic and epigenetic factors that could modulate renal disease progression. For this purpose, clinical data, urine and blood from 30 patients affected by FHHNC and 6 control individuals were collected from around Spain, being them the majority of patients diagnosed of FHHNC in this territory. The analysis of the clinical data allowed evaluating the differences in the evolution of the renal disease according to sex and genotype, classifying patients according to the annual decline of renal function (fast, moderate and slow renal progression), identifying clinical biomarkers of prognosis, and evidencing the high intrafamilial phenotypic variability. The study for the identification of gene variants in homozygosis associated with both extreme phenotypes (fast and slow renal progression) was carried out with data obtained from exome sequencing of the 30 patients included in the cohort. With this strategy, 45 gene variants were identified. Among these, due to the physiological function of the genes where they are located, the rs11207827 (in the PATJ gene) and the rs1050171 (in the EGFR gene) were highlighted. To determine the epigenetic factors involved in FHHNC physiopathology and disease progression, the urinary exosome-like vesicles (uEVs) were used as a non-invasive source of information on renal cellular processes. Microarray technique was used to analyze the expression pattern of miRNAs contained in uEVs of the 20 patients who maintained functional native kidneys. Twenty-four miRNAs were identified differentially expressed in all patients when compared with the control group, and 43 in the subset of patients homozygous for the p.G20D mutation in CLDN19. The comparison of patients of both sexes showed only the under-expression of the miR-1915-5p in males. Finally, 4 miRNAs were differentially expressed in patients with moderate to slow progression of renal disease, and 8 within the subgroup of patients homozygous for the p.G20D mutation in CLDN19. Systems biology and the use of artificial neuronal networks have allowed to associate the results obtained with crucial biological processes in FHHNC physiopathology such as renal fibrosis and calcium and magnesium transport, among others. This work, through two complementary strategies, has allowed increasing the knowledge of the physiopathology of FHHNC and, for the first time, determining clinical, genetic and epigenetic factors involved in renal disease progression. From a translational perspective, this thesis has identified new possible prognostic biomarkers of FHHNC as well as novel therapeutic targets that could allow modulating the severity of the disease and, in the best case, to cure it.
Loc, Ton That Tung, and n/a. "Assessing the spoken English of Vietnamese EFL teacher-trainees." University of Canberra. Education, 1989. http://erl.canberra.edu.au./public/adt-AUC20060818.142405.
Full textKwon, Jong-Won. "Formation and growth of Ir?Hf layers at Ir/HfC interfaces between 1900?C and 2200?C /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487598748018913.
Full textWang, Wei-Wen William. "Condensation and single-phase heat transfer coefficient and flow regime visualization in microchannel tubes for HFC-134A /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488192119266647.
Full textSigne, Jean-Christian. "Condensation de mélanges non azéotropes de fluides frigorigènes à l'extérieur d'un faisceau de tubes horizontaux." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10064.
Full text陳志瑋. "Study on fault rcover for HFC networks." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/63197608496986589388.
Full textGuo, Xin-Feng, and 郭欣峰. "Timestamp Media Access Control for HFC Network." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/69237624756684255531.
Full text義守大學
資訊工程學系
90
Providing QoS guarantees in Hybrid Fiber Coaxial (HFC) networks is a very important and challenging problem. Medium Access Control (MAC) protocol and upstream channel scheduling algorithm are two key mechanisms that will affect the degree of QoS guarantees of HFC networks. Due to the long round-trip propagation delay, uncertain request access delay, and resource reservation without time information, the upstream channel scheduler in the headend cannot obtain the real cell arrival time at the stations. Thus, with the same input traffic, the cell transmission order in HFC networks would be different to the order in traditional switching networks. Therefore, this thesis proposes a new MAC protocol, called Time-stamp General-Contention Resolution Algorithm (TG-CRA), to provide the cell arrival time information to the upstream scheduler in the headend. In order to reduce the overhead of the time information, a linear offset scheme is used to stamp the arrival time information of new arrival cells on the request. Compare to the G-CRA algorithm, simulation result shows that the TG-CRA algorithm can yield better performance in reducing the uncertain request delay and cell access delay. The variance of cell access delay is also reduced, thus the TG-CRA algorithm can provide better mean delay jitter.
lee, Chun-Hong, and 李俊弘. "MAC Protocols over HFC in Interactive CATV Network." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/52059938727494676679.
Full text國立交通大學
資訊科學學系
86
To provide residential users with multimedia interactive services, ahigh bandwidth access network solution is required. In this work, we focus on using existing CATV networks to provide high bandwidth interactive services. We first introduce the HFC(Hybrid FiberCoax) architecture of CATV network adnd idscuss the problems in providingtwo way communication over HFC. Second, we discuss the important issues in upstream channel protcol design: 1) overlapping the collision resolution anddata transmission to archive best usage of bandwidth, in which we examine how to arrange the request mini-slots and data transmission; 2) resolving collision, in which we discuss several traditional collision algorithms; 3)resolving the synchronization problem, in which we propose our solution to getthe RTC(Round Trip Correction) parameter. Third, we introduce several proposed IEEE 802.14 protocols for upstream channel and compar these protocols.
Wu, Hui-Chun, and 吳慧君. "Best Selection of Refrigerant Compressor with HFC-245fa." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/ub4vrn.
Full text國立臺北科技大學
能源與冷凍空調工程系碩士班
101
The study intends to select from the market a compressor that meets the operation specifications of HFC-245fa refrigerant, and use the compressor to achieve effectiveness of HFC-245fa. After experiments are conducted, the study employs theoretical analysis and actual compression system to compare the difference among refrigerating and heating capacities, COPL and COPH under different evaporation temperatures and condensing temperatures. Research results show that HFC-134a refrigerant is most similar to HFC-245fa refrigerant. The study conducts actual simulation tests and measurement of these 2 refrigerants under 9 conditions (TYPE 1 ~ TYPE 9) that use 3 different condensing temperatures 7.2oC, 12.2oC, 17.2oC (HFC-134a) and 49oC, 55oC, 60oC (HFC-245fa) and 3 different evaporator temperatures 35oC, 45oC, 55oC (HFC-134a) and 80oC, 92oC, 103oC (HFC-245fa). Test results show that CAPH, CAPL, COPH and COPL of HFC-245fa are 74%~85% of those of HFC-134a. As to compressor, compressor power loss actually produced by HFC-245fa is 110~112% of that of HFC-134a. These results show that overall efficiency in terms of COP can reach as high as 80%; power loss of compressor increases by 10%; and its operating state was close to that of HFC-134a. Therefore, the compressor can be selected to load HFC-245fa.
Wu, Chia-Jen, and 吳加任. "A HFC MAC Protocol for Interactive CATV Networks." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/48903837986033878154.
Full text國立交通大學
資訊科學學系
84
While ATM (Asynchronous Transfer Mode) serves as the backbone of our NII (National Information Infrastructure), the prevailing cable TV networks may serve as the NII community networks that span the infrastructure into the homes. However, in order to support these services to the residential users, the community cable TV networks have to be redesigned to support 2-way interactive communication. In this work, we propose PCUP (Pipelined Cyclic Upstream Protocol) as the upstream MAC (Medium Access Control) protocol for HFC (Hybrid Fiber Coax) community access network. PCUP is designed with the intention of pipelining the upstream channel. This is achieved by proper station positioning, which measures the station propagation offset from the headend, and transmission scheduling, which assigns each station the transmission starting time and duration in a cycle. By taking into account the propagation offsets and the transmission times, transmitted cells can appear back-to-back, i.e. pipelined, at the headend. Since only the active stations are scheduled to transmit in a cycle, a membership control mechanism, which runs a contention-based tree walk algorithm, is executed periodically to allow the stations to join or leave. We evaluate the behavior of our protocol through simulations to show the effectiveness with respect to loss ratio, throughput, delay, and setup latency. Comparisons with R-ALOHA (Reservation Slotted ALOHA) and CSMA/CD are also made. The results confirm PCUP's excellent performance.
Wong, J. K., and 翁佳愷. "DWDM EDFA Design and Implementation for HFC Systems." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/83976018519519490964.
Full text國立交通大學
電信工程系
87
In this thesis, we have designed and implemented EDFAs for HFC networks applications. We first studied the properties of EDFA, especially the gain model and gain dynamics. Finally, we designed and implemented two kind of EDFAs, one for power amplifiers in the head end and another one is suitably used with DWDM techniques.
Břenek, Roman. "Automatické rozpoznávání zpěvu ptáků." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-178596.
Full textLin, Chin Feng, and 林晉鋒. "Dynamic Two-Way Data Communications Study over HFC Networks." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/73513168651531686339.
Full textLai, Hung-Chang, and 賴宏昌. "Adaptive contention period for performance improvement in HFC networks." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/82134790061873933830.
Full textChien, Chih-Ching, and 簡誌慶. "Study of hflC and related genes in tellurite reduction in Pseudomonas sp. TeU." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/22618206184562580129.
Full text元智大學
生物科技與工程研究所
99
A Pseudomonas strain TeU resistant to tellurite (TeO32-) and cadmium (Cd2+) ions was isolated from heavy-metal contaminated sediments by enrichment. Transposon mutagenesis of strain TeU resulted in mutants exhibiting Cd2+ sensitivity (Strain BU21) and one with decreased ability to reduce tellurite (strain AU08). Genes encoding an HflKC complex and an putative metallopeptidase were identified to be associated with the bacterium’s ability for tellurite reduction and cadmium resistance, respectively. We have cloned and sequenced the hflC and metallopeptidase gene of strain TeU. Metallopeptidase gene of strain TeU was cloned and expressed in E. coli in order to investigate if the protein could improve the bacterium’s ability to resist cadmium.Transmission electron microcopy was also employed for to observe metal precipoitation when strain TeU grown in the medium containing tellurite.
Tseng, Chih-Yuan, and 曾志遠. "Two-Step Growth of MOCVD Copper Using Cu(hfac)2 as the Precursor." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/67277989140551696758.
Full text國立臺灣科技大學
化學工程系
90
The purpose of this paper is to investigate the two-step growth of MOCVD copper using Cu(hfac)2 as the precursor. In the first step, we pre-deposit Cu2O films with water as the additive because precursor’s partial pressure is unstable during deposition without water additive. In contrast to H2, H atoms which are produced due to dehydrogenation reaction of ethanol alcohol can be used to reduce Cu2O films at lower temperatures and enhance the reaction rate .The Cu atom in Cu2O films(24%) is the catalyst. The mixture of ethanol alcohol and water can be used to increase Cu atoms in Cu2O films (50%). More Cu atoms in the Cu2O films can cause the increase of nucleation sites, decrease of grain size, and then increase of grain density.
Nitinkumar, D. Banker. "Development Of An Activated Carbon+ HFC 134a Adsorption Refrigeration System." Thesis, 2006. http://hdl.handle.net/2005/443.
Full textWu, Chia-Jen, and 吳佳任. "Two-phase Minislots Assignment Algorithm for HFC QoS Service Provisioning." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/75413132228267039101.
Full text國立交通大學
資訊科學系
88
Data-Over-Cable Service Interface Specifications v1.1 (DOCSIS1.1), developed for data transmission over the Hybrid Fiber Coaxial (HFC) networks, defines five upstream services to support per-flow Quality of Services (QoS). The cable modem termination system (CMTS) has to periodically grant, based on the QoS parameters, upstream transmission opportunities to the QoS flows. However, packets may be dropped while several flows demand the same interval for transmission. In this paper, we propose the two-phase, the scheduling sequence determination phase and the minislot assignment phase, minislots scheduling algorithm to reduce the QoS violation rate. In the scheduling sequence determination phase, the flow whose packets are with the highest probability of being dropped is scheduled first. Then, in the minislot assignment phase, the scheduler allocates the interval with minimal probability of QoS violation. The simulation results demonstrate that our scheduling algorithm can reduce QoS violation rate up to 70% compared with first-come-first-serve-random-selection algorithm. The two-phase minislots scheduling algorithm can work within the framework of DOCSIS1.1 standard.
Sun, Chung-Kang, and 孫仲康. "Performance Analysis of HFC-152a Applied to Refrigerator and Dehumidifier." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/35dje4.
Full text國立臺北科技大學
能源與冷凍空調工程系碩士班
102
The main purpose of this study is to analyze and discuss the effectiveness of the green refrigerant HFC-152a as a replacement for the refrigerant HFC-134a. Two experiments were conducted, involving one refrigerator and one dehumidifier, respectively, both of which are commercially available and vapor compression cycle system based. In the experiments, these appliances were initially tested for refrigerant performance with their original HFC-134 refrigerant systems and then tested with the alternative refrigerant HFC-152a. Subsequently, analysis was performed to compare the differences in performance between the two types of refrigerant systems. Experiment results show that in the experiment where 30g HFC-152a replaced the originally used 50g HFC-134a in one 95L household refrigerator without changing system components and replacing the refrigeration oil, HFC-152a exhibits overall performance close to that of the refrigerant R134a and superior performance with about 11% less in average power consumption and a significant decrease of about 40% in refrigerant filling amount relative to the refrigerant HFC-134 originally used in the vapor compression cycle system. In the other experiment where 100g HFC-152a replaced the originally used 125g HFC-134a in one household dehumidifier with 6L dehumidification capacity, the system exhibits optimal overall performance exhibits optimal performance across parameters with about 20% less in refrigerant filling amount, an increase of about 7% in dehumidification capacity and about 5% less in average power consumption. All of these results prove that HFC-152a is able to replace HFC-134a.
Ju, Huei-Jiun, and 朱蕙君. "The Effects of HFC MAC Control Mechanism on TCP Performance." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/12820040409842047159.
Full text國立臺灣大學
電機工程學研究所
89
Hybrid-Fiber Coaxial networks have emerged as one of the premier technologies to deliver broadband access to the homes, and the lots of applications on it using TCP as transport layer protocol. In this thesis, we investigate the effects of HFC MAC control protocol on TCP performance and propose a new adaptive FCFS MAC scheduling and allocation algorithm which comprising "Fast Request Transmission" and "Long Packet Deferring" mechanisms, which can help improve the TCP performance substantially in terms of downstream throughput, upstream channel access delay and give good balance on downstream and upstream traffic. In addition, we also introduced an analytical model for TCP Reno on DOCSIS HFC networks, which can analyze and quantify the TCP performance characteristics on DOCSIS, and we developed a DOCSIS v1.1 MAC layer module for ns2, which can be further used to conduct simulation using different traffic sources on DOCSIS HFC networks. The mechanism "Fast Request Transmission" mainly designed to degrade the asymmetric characteristics in HFC networks for improving the downstream throughput and shorten the upstream access delay, while "Long Packet Deferring" mechanism is mainly designed to balance the downstream TCP traffic and upstream TCP traffic for achieving good and fair TCP performance in both direction.
Vašourková, Zuzana. "Ekologické hodnocení a ekonomický význam lesnické farmy HFC v Nikaragui." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-168802.
Full textChen, Gene, and 陳昭慶. "A Study on the MOCVD Copper Films using (hfac)CuI(COD) as the Precursor." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/27326631557598785316.
Full text國立臺灣科技大學
化學工程系
97
The feasibility of using a metal-organic chemical vapor deposition (MOCVD) technique with hexafluoroacetylacetonate-copper(I)- cycloocta-1,5-diene (hfac)CuI(COD) as a precursor to achieve the deposition of a thin and conformal copper film was examined. Self-synthesis of [(hfac)CuI(COD)] and characterization with H1-Nuclear Magnetic Resonance Spectrometer (H1-NMR) and Fourier-Transform Infrared Absorption Spectrophotometer (FTIR)、differential scanning calorimetry (DSC) where performed and (hfac)CuI(COD) was confirmed to be the product. The kinetics of disproportionation reaction of (hfac)CuI(COD) was investigated by the use of DSC with different heating rates in dynamic nitrogen atmosphere. First, the activation energies (Eas) of the disproportionation reaction were estimated with model-free isoconversional methods respectively. The Eas were found to fall within the range between 17.6 and 18.7 kJmol-1, with no temperature and heating rate effects observed. Then, when the Ea was ascertained, the model-fitting methods with least square fitting procedure were adopted to determine the kinetic model for the disproportionation reaction. As a result, the disproportionation reaction follows second-order reaction kinetics. Second, the deposition of thin films on TaN0.46 (-Ta(N)(bcc))、TaN0.82(f.c.c-TaN) and TaN1.12 (amorphous+f.c.c-TaN) substrates was achieved in a cold-wall CVD reactor. On TaN0.46 substrate, the surface morphology of the Cu growth at deposition temperature 140, 190 and 230℃ were followed Volmer-Weber type to form a smooth and continuous film in 5minute of deposition time. On TaN0.82 substrate, the surface morphology of the Cu growth at deposition temperature 190℃ were followed Frank-Van der Merwethe type. It was found that the flatter and denser copper films, and stronger preferred orientation of Cu(111) were obtained after 5minute of deposition time. On TaN1.12 substrate, the surface morphology of the Cu growth at deposition temperature 190℃ were also followed Frank-Van der Merwethe type and formed the flatter and denser copper films, and stronger preferred orientation of Cu(111) after 7min. Then, the deposition of Cu thin films on TaN0.46、TaN0.82 and TaN1.12 trenches were investigated. On TaN0.46 substrate, a continuous and good step coverage Cu film was obtained at ambient deposition temperature. On TaN0.82 and TaN1.12 trenches, the deposition temperature were decreased down to 140℃. Because the growth rate of copper at 140℃ was followed the surface reaction limited regime, that could be formed smooth and continuous thin copper films. Third, growth kinetics of copper films with MOCVD reaction system using (hfac)CuI(COD) as the precursor was studied. In this research, the kinetic data of MOCVD Cu thin films as a function of deposition temperature and partial pressure of precursor were investigated. It was found that the growth rate of copper between 140~190℃ was written surface reaction limited regime with the value of activation energy as 14.82kJ/mol. Through the analysis on the growth kinetics, the kinetic model and mechanism of chemical vapor deposition as follows: Step1: Adsorption of Step2: Disproportionation reaction to form copper and Cu(hfac)2 And the reaction model: Finally, a novel electro-enhanced metalorganic chemical vapor deposition (EEMOCVD) technique for producing copper (Cu) thin films on TaN1.03/Si substrates with (hfac)CuI(COD) as a precursor was investigated in this research. This novel technique features supplying a direct current (DC) to TaN1.03/Si substrates while the deposition of Cu thin films is in progress. Experiments on EEMOCVD yielded fortuitously positive results: (1) the deposited Cu films were superior in quality; and (2) the growth rate of Cu film deposition increased. The above results are more desirable than those achieved through the conventional MOCVD (CMOCVD) technique. The proposed EEMOCVD technique hence proves to be more effective in forming smooth and continuous thin copper films.
Lin, Jung-tsan, and 林榮燦. "The Research of Bandwidth Allocation Mechanism on DOCSIS-Compliant HFC Networks." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/nn6bww.
Full text逢甲大學
資訊工程所
90
With the development of Internet, the demand of bandwidth from user is more and more. To evaluate these resolving plans and the current environment of Taiwan, CATV network is a good resolving plan indeed. In recent standards of CATV, DOCSIS 1.1 is a generally acknowledge standard. There are many mechanisms of standard ensuring QoS (Quality of Service) and the idea of priority. We can promise that those higher priority users could get the higher transmitting performance through giving the different priority to different Cable Modem (CM). We can achieve some level of QoS to protect the base transmitting demand of QoS to users with different level. Data Over Cable Service Interface Specifications v1.1 (DOCSIS 1.1), developed for data transmission over the HFC networks, defines five upstream services to support per-flow QoS. However, it doesn’t define how to schedule these upstream services. In this paper, we study the relationship between DOCSIS 1.1 and QoS, and proposed some advanced methods. In our scheme, the five upstream services are classified into two services — periodic services and aperiodic services. The periodic services are time-sensitive services, and they must provide bandwidth and access delay guarantee. Then the proposed admission control mechanism can handle them. Finally, using EDF、AWFQ algorithm to schedule all services in system effectively and fairly. The analysis and simulation results confirm that the throughput and delay are better than several proposed scheme.
Liu, Chun-Hung, and 劉俊宏. "A Novel Contention Resolution Algorithm for IEEE 802.14 in HFC Networks." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/20941638394152759787.
Full text國立成功大學
資訊工程研究所
88
Hybrid Fiber Coaxial (HFC) system provides a bi-directional cable TV network. HFC network has several characteristics:long propagation delay, indirect collision detection, asymmetric bandwidth, and non-uniform user distribution. Hence a good contention resolution algorithm is important and necessary in HFC networks. For obtaining a better performance, the contention resolution of HFC networks is usually divided into first transmission rule (FTR), which determines when to transmit for new requests, and collision resolution algorithm (CRA), which determines how to resolve the collisions. In IEEE 802.14 Draft, Admission Time Boundary (ATB) is used as the standard of FTR and Q-ary tree algorithm is used as the standard of CRA. In this thesis, a novel contention resolution algorithm, queue-based algorithm, is proposed. By using a queue, collided queue, all collisions in the pervious period are all recorded. The headend then schedule the consequent transmissions according on this collided queue. A measurement-based ATB setting is proposed. It can estimate a more correct number of new requests and set a more proper ATB. From simulation results, its performance is the closest to the ideal among all ATB setting algorithms. Finally, the effect of Q in the Q-ary tree algorithm is also investigated. A dynamic Q setting is necessary when a poor ATB setting algorithm is used.