Littérature scientifique sur le sujet « Heat source identification »
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Articles de revues sur le sujet "Heat source identification"
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Kriegsmann, G. A., et W. E. Olmstead. « Source identification for the heat equation ». Applied Mathematics Letters 1, no 3 (1988) : 241–45. http://dx.doi.org/10.1016/0893-9659(88)90084-5.
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Momose, Kazunari, Tetsuya Murai, Toshihiko Asami et Yoshinobu Hosokawa. « Identification of Heat-Source Using Neural Network. » Transactions of the Japan Society of Mechanical Engineers Series C 59, no 567 (1993) : 3431–36. http://dx.doi.org/10.1299/kikaic.59.3431.
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Erdem, A., D. Lesnic et A. Hasanov. « Identification of a spacewise dependent heat source ». Applied Mathematical Modelling 37, no 24 (décembre 2013) : 10231–44. http://dx.doi.org/10.1016/j.apm.2013.06.006.
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Xie, Yanmei, Caihong Ma, Yindi Zhao, Dongmei Yan, Bo Cheng, Xiaolin Hou, Hongyu Chen, Bihong Fu et Guangtong Wan. « The Potential of Using SDGSAT-1 TIS Data to Identify Industrial Heat Sources in the Beijing–Tianjin–Hebei Region ». Remote Sensing 16, no 5 (22 février 2024) : 768. http://dx.doi.org/10.3390/rs16050768.
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It is crucial to detect and classify industrial heat sources for sustainable industrial development. Sustainable Development Science Satellite 1 (SDGSAT-1) thermal infrared spectrometer (TIS) data were first introduced for detecting industrial heat source production areas to address the difficulty in identifying factories with low combustion temperatures and small scales. In this study, a new industrial heat source identification and classification model using SDGSAT-1 TIS and Landsat 8/9 Operational Land Imager (OLI) data was proposed to improve the accuracy and granularity of industrial heat source recognition. First, multiple features (thermal and optical features) were extracted using SDGSAT-1 TIS and Landsat 8/9 OLI data. Second, an industrial heat source identification model based on a support vector machine (SVM) and multiple features was constructed. Then, industrial heat sources were generated and verified based on the topological correlation between the identification results of the production areas and Google Earth images. Finally, the industrial heat sources were classified into six categories based on point-of-interest (POI) data. The new model was applied to the Beijing–Tianjin–Hebei (BTH) region of China. The results showed the following: (1) Multiple features enhance the differentiation and identification accuracy between industrial heat source production areas and the background. (2) Compared to active-fire-point (ACF) data (375 m) and Landsat 8/9 thermal infrared sensor (TIRS) data (100 m), nighttime SDGSAT-1 TIS data (30 m) facilitate the more accurate detection of industrial heat source production areas. (3) Greater than 2~6 times more industrial heat sources were detected in the BTH region using our model than were reported by Ma and Liu. Some industrial heat sources with low heat emissions and small areas (53 thermal power plants) were detected for the first time using TIS data. (4) The production areas of cement plants exhibited the highest brightness temperatures, reaching 301.78 K, while thermal power plants exhibited the lowest brightness temperatures, averaging 277.31 K. The production areas and operational statuses of factories could be more accurately identified and monitored with the proposed approach than with previous methods. A new way to estimate the thermal and air pollution emissions of industrial enterprises is presented.
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Tsai, Richard, Stanley Osher et Yingying Li. « Heat source identification based on $l_1$ constrained minimization ». Inverse Problems and Imaging 8, no 1 (mars 2014) : 199–221. http://dx.doi.org/10.3934/ipi.2014.8.199.
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Eremin, A. V., E. V. Stefanyuk et L. S. Abisheva. « HEAT SOURCE IDENTIFICATION BASED ON ANALYTICAL SOLUTIONS OF THE HEAT-CONDUCTION PROBLEM ». Izvestiya Visshikh Uchebnykh Zavedenii. Chernaya Metallurgiya = Izvestiya. Ferrous Metallurgy 59, no 5 (1 janvier 2016) : 339–46. http://dx.doi.org/10.17073/0368-0797-2016-5-339-346.
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KUBO, Shiro, Kohzaburo OHNAKA et Kiyotsugu OHJI. « Identification of heat-source and force using boundary integrals. » Transactions of the Japan Society of Mechanical Engineers Series A 54, no 503 (1988) : 1329–34. http://dx.doi.org/10.1299/kikaia.54.1329.
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Hettlich, F., et W. Rundell. « Identification of a discontinuous source in the heat equation ». Inverse Problems 17, no 5 (7 septembre 2001) : 1465–82. http://dx.doi.org/10.1088/0266-5611/17/5/315.
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Ling, Leevan, Masahiro Yamamoto, Y. C. Hon et Tomoya Takeuchi. « Identification of source locations in two-dimensional heat equations ». Inverse Problems 22, no 4 (26 juin 2006) : 1289–305. http://dx.doi.org/10.1088/0266-5611/22/4/011.
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Lu, Zhong-Rong, Tiancheng Pan et Li Wang. « A sparse regularization approach to inverse heat source identification ». International Journal of Heat and Mass Transfer 142 (octobre 2019) : 118430. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2019.07.080.
Texte intégralThèses sur le sujet "Heat source identification"
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Branscome, Ewell Caleb. « A Multidisciplinary Approach to the Identification and Evaluation of Novel Concepts for Deeply Buried Hardened Target Defeat ». Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14092.
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The objective of the work described was to identify and explore a paradigm shifting solution that could offer leap-ahead capabilities to counter current and future DBHT threats while mitigating or eliminating the self-deterrence issue. A multidisciplinary approach to the problem was formulated and implemented. Systematic evaluation of DHBT defeat alternatives lead to the selection of a thermal subterrene as a hypothetical means of providing such a capability. A number of possible implementation alternatives for a thermal subterrene were investigated, resulting in the identification of the RadioIsotope Powered Thermal Penetrator (RIPTP) concept for providing an effectively unlimited, self-contained hard rock penetration capability using near-term technologies. However, the proposed approach was novel and thus required formulation and application of a physics based multidisciplinary analysis code to enable evaluation of design alternatives and analysis of performance. The following disciplinary analyses were composed into a multidisciplinary analysis code for a RIPTP: packing of RIPTP components in available volume; close-contact melting analysis; transmutation of isotope species by neutron activation; reactor neutron economy; radioisotope power generation through decay; metamodelled radiation shielding calculations for a RIPTP; and steady state thermal analyses for a RIPTP in various scenarios. Performance analysis of the identified baseline Thulium-170 RIPTP suggested that the predicted low penetration rate of about 10 meters/day could be a significant negative factor with regards to possible viability of the concept. Consequently, a survey for potentially enabling technologies was performed using an adaptation of the Technology Impact Forecasting (TIF) approach. It was found that the greatest potential for improving performance of the baseline Thulium-170 RIPTP resulted from increasing overall power density of the penetrator. Several possible technology approaches to achieving significantly increased penetration rates are proposed.
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Mohamad, Salman. « EVALUATING THE ORGANIC RANKINE CYCLE (ORC) FOR HEAT TO POWER : Feasibility and parameter identification of the ORC cycle at different working fluid with district waste heat as a main source ». Thesis, Mälardalens högskola, Framtidens energi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-38573.
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New technologies to converting heat into usable energy are constantly being developed for renewable use. This means that more interactions between different energy grid will be applied, such as utilizing low thermal waste heat to convert its energy to electricity. With high electricity price, such technology is quite attractive at applications that develop low waste heat. In the case of excess heat in district heating (DH) grid and the electricity price are high, the waste heat can be converted to electricity, which can bring a huge profit for DH companies. Candidate technologies are many and the focus in this degree rapport is on the so-called Organic Rankine Cycle (ORC) that belongs to the steam Rankine cycle. Instead of using water as a working fluid, organic working fluid is being used because of its ability to boil at lower temperature. Because this technique is available, it also needs to be optimized, developed, etc. to achieve the highest appropriate efficiency. This can be done, for example, by modeling different layouts, analyzing functionality, performance and / or do a simulation of various suitable working fluids. This is the purpose of this degree project and the research parts are to select working fluids suitable at low temperatures (70-120) °C, the difference analysis between the selected fluids and identification of the parameters that most affect the performance. There are many suitable methods to apply to achieve desired results. The method used in this rapport degree is commercial software such as Mini REFPROP, CoolPack, Excel but the most important part is simulation with AspenPlus. The selected and suitable working fluids between the chosen temperature interval are R236ea, R600, R245fa and n-hexane. Three common layouts were investigated, and they are The Basic ORC, ORC with an internal heat exchanger (IHE) and regenerative ORC. The results show that in comparison between 120°C and 70°C as a temperature source and without an internal heat exchanger (IHE), R600 at 70°C, has the highest efficiency about 13.55%. At 110°C n-hexane has the highest efficiency about 18.10%. R236ea has the lowest efficiency 13.16% at 70°C and 16.29% at 110°C. R236ea kept its low efficiency through all results. Without an IHE and a source range from 70 °C up to almost 90 °C, R600 has the highest efficiency and at 90°C n-hexane has the highest efficiency. With an IHE and between (70-90) °C R245fa still has the highest efficiency. With or without IHE and a heat source of 110 °C n-hexane has the highest efficiency 18.10% and 18.40%. R236ea gets the greatest increase 5.2% in efficiency but remains with the lowest efficiency. With Regenerative ORC, n-hexane had an optimal middle pressure about 0.76 bar. The optimal pressure corresponds to a thermal efficiency of 17.52%. The most important identified parameters are the fluid characteristics such as higher critical temperature, temperature source, heat sink, application placement and component performance. The current simulations have been run at some fixed data input such as isentropic efficiencies, no pressure drops, adiabatic conditions etc. It was therefore expected that the same efficiency curve would repeat itself. This efficiency pattern would differ with less or higher values depending on the layout performance. However, this pattern was up to 90 degrees Celsius and gets a very noticeable change by the change of the efficiency for n-hexane. Therefore n-hexane is chosen with Regenerative ORC because it had the highest efficiency at the highest temperature source tested. This is due definitive to the fluid properties like its high critical temperature compared to the other selected fluids. R236ea remains the worst and that’s also related to the fluid properties. It is also important to note that these efficiencies are only from a thermodynamic perspective and may differ when combining both thermal and economic perspectives as well as application placement. These high efficiencies will certainly be lower at more advanced or real processes due to various factors that affect performance. Factors such as component´s efficiency and selection, pipe type and size, etc. To maintain a constant temperature when it’s not, flow regulation is then necessary and that’s also affects the performance. The conclusion is that the basic ORC which does not have an IHE and from 70 up to 90 degrees Celsius, R600 has the highest efficiency. Higher temperature gives n-hexane the highest efficiency. With an IHE and between (70-90) °C R254fa has the highest efficiency. At higher temperature source n-hexane has the highest efficiency. ORC with an IHE has the best performance. The R236ea has the worst performance through all results. With regenerative ORC, an optimal meddle-pressure for n-hexane is 0.76 bar. Important parameters are The properties of the fluid, temperature source, heatsink, Application placement and component performance.Nej
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Dupuis, Quentin. « Identification des caractéristiques d'une carte électronique et de ses composants, et modélisation de leurs comportements thermiques ». Electronic Thesis or Diss., Paris 10, 2023. http://www.theses.fr/2023PA100131.
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Le travail développé dans cette thèse est une contribution à l’identification via des mesures expérimentales des paramètres critiques pour la modélisation thermique d’une carte électronique et de ses composants. Dans une première partie, l’étude de l’évolution temporelle de la température de jonction d’un composant électronique soumis à une puissance thermique constante est proposée, ceci à partir de l’analyse graphique de sa Cumulative Structure Function. La présentation détaillée de toutes les étapes dans la construction de cette dernière est réalisée, ainsi que l’analyse des différents paramètres sensibles. L’identification de manière absolue des paramètres thermiques des différents matériaux d’un composant électronique est irréalisable. Néanmoins une étude relative permettant le calibrage de son modèle numérique détaillé est présentée. La seconde partie de cette thèse est consacrée à l’identification par méthodes inverses des caractéristiques d’un composant encastré au sein d’une carte électronique, à savoir sa position, ses dimensions et la puissance thermique qu’il dissipe. Pour atteindre cet objectif, un modèle numérique 3D basé sur la méthode des volumes finis a été implémenté, pour calculer en régime transitoire les transferts de chaleur par conduction qui s’établisse au sein de la structure d’étude. L’algorithme des gradients conjugués avec calcul de la variable adjointe est utilisé pour estimer les puissances thermiques volumiques dissipées, tandis que son couplage avec une fonction de minimisation unidimensionnelle permet d’identifier la position des sources de chaleur dans la profondeur de la structure. L’application de cette procédure à partir de données issues de simulations numériques ainsi que des mesures expérimentales ont permis de valider la méthode d’inversionThe work presented in this thesis is a contribution to the identification via experimental measurements of critical parameters for the thermal modelling of an electronic board and its components.First, the study of the temporal evolution of the junction temperature of an electronic component stimulated by a constant thermal power is proposed, based on the graphical analysis of its Cumulative Structure Function. All the steps involved in the construction of this function are presented in detail, together with an analysis of the various sensitive parameters. Absolute identification of the thermal parameters of the different materials of an electronic component is not feasible, but a relative study is presented to enable the calibration of its detailed numerical model.The second part of this thesis is devoted to the identification, using inverse methods, of the characteristics of a component embedded in an electronic board, namely its position, its dimensions, and its dissipated thermal power. To achieve this objective, a 3D numerical model based on the finite volume method was implemented to calculate the transient conductive heat transfer within the structure of study. The conjugate gradient algorithm with adjoint variable calculation is used to estimate the dissipated heat power density, while its coupling with a one-dimensional minimisation function permits to identify the position of the heat sources according to the depth of the structure. The application of this procedure to data from numerical simulations and experimental measurements has enabled to validate the inversion method
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Bouzarour, Amina. « Auto-échauffement d'un lit ventilé de matériaux carbonés : cas du bois torréfié Experimental study of torrefied wood fixed bed : Thermal analysis and source term identification ». Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2019. http://www.theses.fr/2019EMAC0012.
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La torréfaction est l'un des procédés de prétraitement thermochimique de la biomasse lignocellulosique qui permet de faciliter le stockage et le transport du matériau, mais aussi d'augmenter la densité énergétique du produit. Néanmoins, le substrat torréfié étant plus réactif, il est plus sujet à des mécanismes exothermiques spontanés pouvant entraîner un auto-échauffement de la matière. Dans le cadre de cette thèse, cette problématique a été étudiée pour le cas du bois torréfié. En effet, il a été question de comprendre les phénomènes responsables de l'auto-échauffement d'un lit de biomasse ventilé par un gaz oxydant à basse température. Pour ce faire, des scenarii d'auto-échauffement de plaquettes de bois torréfié ont été créés sous une atmosphère oxydante. Des expérimentations ont été conduites à l'échelle pilote dans un réacteur à lit fixe de 12 L. Au cours de ces essais, nous avons démontré que l'auto-échauffement est intensifié lorsque le débit du gaz oxydant est faible et sous une fraction d'oxygène élevée. Par ailleurs, la chaleur produite au cours de l'auto-échauffement du lit de bois a été estimée sur la base d'un bilan de chaleur et des données thermiques. Des paramètres cinétiques apparents et une chaleur de réaction associés à l'auto-échauffement ont été déduits. D'autre part, dans le but d'appréhender les phénomènes exothermiques caractérisant l'auto-échauffement, des essais d'oxydation à basse température sont réalisés à petite échelle (en ATG/ATD). Des modèles cinétiques ont ensuite été mis en œuvre pour distinguer et quantifier les mécanismes repérés expérimentalement. Ces deux approches ont permis de mettre en avant trois principaux mécanismes intervenant lors de l'oxydation à basse température : l'adsorption chimique de l'oxygène sur le réactif, la décomposition des complexes oxygénés formés à l'adsorption et une réaction d'oxydation directe. Dans une approche plus orientée vers des problématiques à l'échelle industrielle de l'auto-échauffement, un modèle numérique couplant cinétique chimique et transferts de matière et de chaleur a été conçu, à l'échelle du lit de particules. Ce modèle a permis de prédire de façon raisonnable la thermique du lit de bois torréfié à fort débit de ventilation. Il a été ensuite extrapolé à l'échelle industrielle pour simuler le comportement thermique d'un silo de stockage subissant un auto-échauffementTorrefaction is one of the thermo-chemical pretreatment processes of lignocellulosic biomass that facilitates both the storage and transport of the material and increases the energy value of the product. However, as the torrefied substrate is more reactive, it is more prone to spontaneous exothermic mechanisms that can lead to self-heating of the material. This issue is not well investigated in the case of torrefied wood since its industrial application is mainly in the test phase. For this reason, this topic is further studied throughout this thesis. Indeed, the aim was to understand the phenomena responsible for the self-heating of a bed of biomass ventilated with oxidizing gas at low temperature. To do this, self-heating scenarios of torrefied wood chips were created under an oxidizing atmosphere. Pilot-scale experiments were conducted in a 12 L fixed-bed reactor. During these tests, we demonstrated that self-heating is intensified when the oxidizing gas flow rate is low and under a high oxygen fraction. In addition, the heat produced during the self-heating of the wooden bed was estimated on the basis of a heat balance and thermal data. Then, the source term was correlated to the oxygen fraction and temperature in a simplified model. The apparent kinetic parameters and heat of reaction associated with self-heating were derived from this. On the other hand, in order to understand the exothermic phenomena characterizing self-heating, low temperature oxidation tests are carried out on a small scale (ATG/ATD). On the basis of these analyses, kinetic models were developed to distinguish and quantify the mechanisms identified experimentally. These two approaches have made it possible to highlight three main mechanisms involved in low-temperature oxidation: chemical adsorption of oxygen on the reagent, decomposition of the oxygen complexes formed during adsorption and a direct oxidation reaction. In a more problem-oriented approach to industrial-scale self-heating, a numerical model coupling chemical kinetics and mass and heat transfers was designed at the scale of the particle bed. This model provided a reasonable prediction of the thermal performance of the torrefied wood bed under high ventilation flow. It was then extrapolated to an industrial scale to simulate the thermal behaviour of a storage silo undergoing self-heating
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Frisk, Malin, et Elise Ramqvist. « Identification of waste heat sources in Uppsala - with potential use in Bergsbrunna as a case study ». Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-245231.
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Reducing energy losses within the energy system is essential for a sustainable future. Waste heat usage could be a part of an increased energy efficiency and a sustainable use of resources. Uppsala Municipality aims to become a climate positive municipality in 2050, with negative net emissions of CO2. Increasing waste heat usage represent one possible measure in order to achieve this goal. Vattenfall AB is the local supplier of heat, cooling, steam and electricity in Uppsala and has a strong ambition for a sustainable future. The main objective of this work is to identify, quantify and classify low and high temperature waste heat sources within Uppsala Municipality. Also, the objective is to assess the potential contribution from low temperature waste heat sources for a low temperature district heating network in Bergsbrunna, a planned urban area in Uppsala. The contribution was evaluated based the technical and economic feasibility. To reach the objectives, a survey on the waste heat and waste heat generating processes within different businesses in Uppsala Municipality was created and sent to 374 businesses of different type within the Municipality. The selection of targeted businesses types was based on the findings of potential waste heat within these businesses in the literature and limited to available contact information. This work contributes with profiles of the waste heat transfer rate from a number of businesses on an hourly basis, which can be applied to any area to estimate the waste heat potential. Waste heat profiles were developed for grocery stores of different sizes, a restaurant, a hotel, an ice rink, and an indoor swimming pool. In addition to this, a decision-making matrix was created to facilitate comparison of the waste heat sources. The considered waste heat parameters are quantity, temperature, daily and seasonal variations and distance to the present district heating network. Calculations of the theoretical amount of low temperature waste heat sources in Uppsala Municipality have been made based on the developed waste heat profiles and the number of identified businesses. The results show that the quantified amount of low temperature waste heat within Uppsala Municipality amount to approximately 62 GWh annually, which is available at temperatures between 22°C to 55°C. From the developed waste heat profiles, it was found that a grocery store has a potential or delivering between 1,200 MWh and 3,500 MWh waste heat annually depending on its size. A restaurant could potentially deliver 90 MWh waste heat annually, whereas a hotel has the potential of 80 MWh. Additionally, an ice rink and an indoor swimming pool could potentially deliver 1,400 MWh and 600 MWh of waste heat, respectively. By means of the decision-making matrix, grocery stores and ice rinks were presented as the most prominent low temperature waste heat sources in Uppsala Municipality. Mostly due to the continuity of waste heat delivery, but also thanks to favorable geographic positions. When evaluating the contribution of waste heat sources to a low temperature district heating network in Bergsbrunna, it was seen that the waste heat contributed to almost 14% of the heat demand if the waste heat temperature was raised to 65°C with heat pumps. However, the economic assessment shows that the lowest cost is approximately 0.34 SEK/kWh for raising the temperature to 65°C. Additionally, it was seen that the temperature of the waste heat could be raised to 85°C to be utilized in the conventional district heating network. However, the associated production cost where higher in comparison with the cost of utilizing the waste heat in a network with a lower design temperature, where the lowest cost is approximately 0.39 SEK/kWh. It should be mentioned that a number of assumptions have been made to calculate the waste heat potential. The most important assumption is addressed to the fact that the potential is based on secondary data of an average energy use in different buildings on a national level, which was not intentionally collected for calculating waste heat potential. The urban planning used in the case-study of Bergsbrunna is based on several assumptions. Thereby, it is not certain that this represents Bergsbrunna in the future or another area of the same size. Also, the heat production cost only includes approximated investment and installation costs of the heat pump and the electricity costs, which are based on historical data.Att hushålla med jordens resurser är en av det viktigaste faktorerna för en hållbar framtid. Tillvaratagande av spillvärme kan vara ett sätt att öka energieffektiviteten och utnyttjandegraden av resurserna. Uppsala kommun har som mål att vara en klimatpositiv kommun år 2050, vilket innebär negativa utsläpp av koldioxid. Spillvärmetillvaratagande presenteras som en potentiell åtgärd för att uppnå visionen om en klimatpositiv kommun. Vattenfall AB är värme-, kyl-, ång- och eldistributör i Uppsala och har ett starkt mål inom hållbarhet. Vattenfall är en samarbetspartner till Uppsala och ser ett intresse i möjligheterna för spillvärme i ett framtida energisystem. Det här examensarbetet undersöker vilka spillvärmekällor som finns i Uppsala kommun och approximerar den teoretiska mängden lågtempererad spillvärme från typiska verksamheter med spillvärmegenererande processer. Dessutom undersöks hur stor mängd av spillvärmen som kan nyttjas i den planerade stadsdelen Bergsbrunna och hur stor del av värmebehovet i stadsdelen som spillvärmen kan täcka genom ett lågtempererat fjärrvärmenät. I syfte att undersöka hur mycket och i vilken form spillvärme samt vilka spillvärmealstrande processer som förekommer inom olika verksamheter i Uppsala kommun skapades en enkät, vilken skickades ut till totalt 374 olika verksamheter. Urvalet av de olika verksamhetstyperna baserades på den spillvärmepotential som tidigare studier visat samt begränsades av tillgänglig kontaktinformation till de identifierade verksamheterna. Timbaserade spillvärmeprofiler togs fram för ett antal verksamheter, vilka är livsmedelsbutiker, hotell och restauranger samt ishallar och simhallar. Dessa profiler kan nyttjas som bas när spillvärmepotentialen ska approximeras i ett område där en eller flera av dessa verksamheter finns. Dessutom togs en bedömningsmatris fram som förslagsvis används då spillvärmekällans olika parametrar ska summeras och potentialen jämföras med andra spillvärmekällor. Utifrån de framtagna spillvärmeprofilerna kunde en teoretisk potential av de låggradiga spillvärmekällorna i Uppsala kommun beräknas. Resultaten visar att det approximativt finns 62 GWh tillgänglig låggradig spillvärme årligen inom kommunen samt att dess temperatur varierar mellan 22°C och 55°C. Spillvärmeprofilerna visar dessutom att en livsmedelsbutik har en årlig spillvärmepotential mellan 1 200 och 3 500 MWh, beroende på butikens storlek. En restaurang och ett hotell skulle potentiellt kunna leverera 90 MWh respektive 80 MWh spillvärme årligen. En ishall har en potential att leverera 1 400 MWh spillvärme medan en simhall har en årlig spillvärmepotential på 600 MWh. I den planerade stadsdelen Bergsbrunna kan spillvärmemängden från 14 spillvärmekällor i form av livsmedelsbutiker, en ishall, en simhall, ett hotell och restauranger täcka nästan 14% av det årliga värmebehovet om spillvärmetemperaturen höjs till 65°C med värmepumpar. Dessutom höjdes temperaturen av spillvärmen till 85°C för att kunna användas i dagens fjärrvärmenät. Den ekonomiska analysen visar att den lägsta produktionskostnaden uppgår till ungefär 0.34 SEK/kWh för temperaturhöjning till 65°C, jämfört med den lägsta produktionskostnaden som uppgår till ungefär 0.39 SEK/kWh för temperaturhöjning till 85°C. Flera antaganden har gjorts för att beräkna spillvärmepotentialen i Uppsala. Det viktigaste antagandet är att andrahandsdata av medelenergiförbrukning i olika typer av verksamheter kan användas för att beräkna spillvärmepotentialen. Dessa mätvärden var inte initialt uppmätta för att beräkna spillvärmepotentialen. Stadsplaneringen av Bergsbrunna är också baserat på flera antaganden och därav är det inte säkert att den representerar den framtida stadsdelen eller ett annat område av samma storlek. Slutligen, de ekonomiska beräkningarna inkluderar endast investerings- och installationskostnaderna av värmepumpen och elkostnaden för att höja spillvärmetemperaturen, som är baserad på historisk data.
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Yu, Jianbin. « Identification of new sources and mapping of QTL for FHB resistance in Asian wheat Germplasm ». Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/258.
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Ho, Tzu-Hsin, et 何子炘. « PDE Parameters Identification of a Copper Rod Heat Conduction System with a Boundary Heat Source ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/89904218248416359208.
Texte intégralRésumé :
碩士國立中興大學
電機工程學系所
98
This thesis is on PDE parameters identification of a heat conductive copper rod with a boundary heat source. A copper rod, 400mm in length and 38mm in diameter, is heated by an electrical heater with a pulse-width-modulated (PWM) solid state relay (SSR) control module from one boundary point. The temperature distribution of the copper rod is sampled and collected into a TMS320LF 2407A digital signal processor (DSP) manufactured by Texas Instruments (TI). The data is then plotted and analyzed by using Matlab software packages. In addition, the copper heat conduction equation and the derived dynamic model in Chapter IV will be applied to the conversion process of the continuous-time boundary control into the discrete-time sampled-data representation by using the Zero-Order-Hold (Z.O.H) process. The boundary conditions of the heat conduction equation are converted into homogeneous boundary conditions before applying the Matlab pdepe.m simulation functions. Finally, the experimental data are compared against the simulation data for confirmation of the PDE system parameters identification for the copper rod heat conduction system.
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Chang, Chih-Wen, et 張致文. « Applications of Novel Approaches to Backward Heat Conduction Problems and Groundwater Pollution Source Identification Problems ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/82818224428386201487.
Texte intégralRésumé :
博士國立臺灣海洋大學
系統工程暨造船學系
97
This dissertation investigates two inverse problems of parabolic equations using four different numerical methods. These problems are ill-posed because the solution、if it exists、does not depend continuously on the measured data. Even many researchers have proposed lots of methods to overcome these ill-posed problems; however、an effective numerical scheme to tackle these problems is still pending. The backward heat conduction problem (BHCP) and the groundwater pollution source identification problem governed by the backward advection-dispersion equation (ADE) are tackled by the backward group preserving scheme (BGPS)、the Lie-group shooting method (LGSM)、the quasi-boundary semi-analytical method、and the fictitious time integration method (FTIM)、respectively. First、these two ill-posed problems are analyzed by considering the stable semi-discretization numerical schemes and then、the resulting ordinary differential equations at the discretized spaces are numerically integrated towards the time direction by using the BGPS. Nevertheless、the LGSM is employed to find the unknown initial conditions. The key point is based on the erection of a one-step Lie group element G(T) and the formation of a generalized mid-point Lie group element G(r). Then、by imposing G(T) = G(r) we can seek the missing initial conditions through a minimum discrepancy of the target in terms of the weighting factor In addition、the Fourier series expansion technique is used to calculate the temperature field and the concentration field by using the quasi-boundary semi-analytical method. Then、we consider a direct regularization by adding an extra term or in the final time condition to obtain a second kind Fredholm integral equation for u(x、y、0) or C(x、y、0). The termwise separable property of the kernel function allows us to transform the backward problem into a two-point boundary value problem and therefore、a closed-form solution is derived. After that、by using the FTIM、we transform the original parabolic equation into another parabolic type evolution equation by introducing a fictitious time variable、and adding a fictitious viscous damping coefficient to enhance the stability of numerical integrations of the discretized equations by employing a group preserving scheme. Since four new computational algorithms are based on a concrete theoretical foundation、they offer effective approaches for solving these inverse problems. At last、several designed numerical examples especially with noisy data will be carefully discussed and validate these proposed methods.
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Al-Khalidy, Nehad A. Hussen. « Applying inverse techniques for identification of thermal effects during welding process with moving heat source ». Rozprawa doktorska, 1996. https://repolis.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=3118.
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Al-Khalidy, Nehad A. Hussen. « Applying inverse techniques for identification of thermal effects during welding process with moving heat source ». Rozprawa doktorska, 1996. https://delibra.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=3118.
Texte intégralLivres sur le sujet "Heat source identification"
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Blasi, Francesco, et Paolo Tarsia. Therapeutic approach in haemoptysis. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0127.
Texte intégralRésumé :
The aim of diagnostic studies in patients with haemoptysis is two-fold—locate the source of bleeding and identify the underlying cause. A chest X-ray may be informative regarding conditions involving the lung parenchyma, pulmonary vasculature, or the heart, but may be normal in 20–40% of cases. A chest CT scan may allow correct localization of the bleeding site in 65–100% of cases. Contrast-enhanced CT scans allow high resolution angiographic studies that may be useful prior to planning bronchial arterial embolization. Bronchoscopy may allow identification of the site of bleeding, identify the underlying cause, help clear the airways from blood clots favouring gas exchange, and be a means to stop the bleeding. Treatment of haemoptysis varies from outpatient management to intensive care unit admittance. Choice of optimal management depends on the intensity of bleeding, degree of respiratory compromise, and severity of underlying cardiorespiratory status. Important steps in the management of patients with massive haemoptysis include resuscitation, airway protection and patient stabilization as the priority, subsequent localization of the site of bleeding, and specific interventions to stop the bleeding and prevent recurrence. Bronchoscopy may be useful in stopping bleeding through use of cold saline lavage, use of topical vasoconstrictive agents, or temporary endobronchial tamponade with a balloon catheter. The procedure of choice in many cases is selective bronchial artery embolization. With this procedure immediate control of bleeding may be obtained in 70–95% of patients, although recurrence has been reported in 10–30% of cases.
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Rossi, Michael. James Herriot. Greenwood Publishing Group, Inc., 1997. http://dx.doi.org/10.5040/9798400673535.
Texte intégralRésumé :
This study examines James Herriot's five major books as carefully crafted volumes of autobiography based on the building block of the short story. In each of these works Herriot explores the fundamental choice of values underlying a happy and successful life. In his vision the bonds of affection and mutual dependence between all creatures, human and animal, form an enduring theme that lies at the heart of the choices he makes in his personal and professional life. This study will help the reader to understand the relationship between Herriot's stories and each book as a whole and to appreciate Herriot's work in the context of twentieth-century anxieties about identity and meaning. Following a biographical chapter that describes the relationship between Herriot's life and literary work, Rossi discusses the genre of autobiography, the relationship between truth and fiction in modern autobiography, and Herriot's use of the genre. A separate chapter is then devoted to each of Herriot's works in turn: All Creatures Great and Small, All Things Bright and Beautiful, All Things Wise and Wonderful, The Lord God Made Them All, and ^Every Living Thing. The discussion of each work includes sections on plot development and narrative structure, character development, thematic issues, and alternative critical approaches that may be fruitfully applied to the book. Helpful appendices contain identifications of minor characters in the works. A complete bibliography of all of James Herriot's works, critical sources, and a listing of reviews of all of his works completes the volume. Because of the popularity of Herriot's work among adults and young adults this companion will be a key purchase for school and public libraries.
Chapitres de livres sur le sujet "Heat source identification"
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Vasil’ev, V. I., V. V. Popov et A. M. Kardashevsky. « Conjugate Gradient Method for Identification of a Spacewise Heat Source ». Dans Large-Scale Scientific Computing, 600–607. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-73441-5_66.
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Beaubier, B., K. Lavernhe-Taillard, R. Billardon, C. Boucq, P. Laloue et B. Darciaux. « Identification of Welding Heat Sources from Infrared Temperature Measurements ». Dans Conference Proceedings of the Society for Experimental Mechanics Series, 199–206. Cham : Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00876-9_24.
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Charlès, S., et J.-B. Le Cam. « Hyperelastic model identification from heat source fields ». Dans Constitutive Models for Rubber XI, 183–87. CRC Press, 2019. http://dx.doi.org/10.1201/9780429324710-33.
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Lin, Feng-Tsai, et John C.-C. « Modelling of Transient Ground Surface Displacements Due to a Point Heat Source ». Dans Modelling, Simulation and Identification. Sciyo, 2010. http://dx.doi.org/10.5772/10024.
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Lin, Feng-Tsai, et John C.-C. « Closed-Form Solutions of the Cross-Anisotropic Stratum Due to a Point Heat Source ». Dans Modelling, Simulation and Identification. Sciyo, 2010. http://dx.doi.org/10.5772/10023.
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Liu, Xiaolong, Jushang Li, Ruitong Zhang, Hongjie Jiang, Xikuan Chen, Jihao Cheng et Fucheng Liu. « Transient Quantitative Identification Algorithm Based on Laser Impulse Response ». Dans Proceedings of the 2022 International Conference on Smart Manufacturing and Material Processing (SMMP2022). IOS Press, 2022. http://dx.doi.org/10.3233/atde220835.
Texte intégralRésumé :
In order to improve the measurement accuracy of transient heat flow based on laser pulse response technology, a dynamic calibration algorithm of heat flow based on pulse response of fiber semiconductor laser is proposed. The system uses a high-power fiber semiconductor laser to generate modulated excitation, and quantitatively detects the transient heat flow energy in the form of pulsed radiation. The light intensity of the light source is adjusted by the homogenization of the light spot, and the energy measurement is completed with a Gardon meter. The data acquisition card and signal analysis circuit are used to realize the high-speed calculation and acquisition of the heat flow signal. Using the transient quantitative identification algorithm, the dynamic test performance of a circular foil heat flow meter of the GD series is tested and calibrated. The simulation analysis of the system’s ability to modulate the signal verifies the feasibility of the system’s light source modulation. A transient quantitative identification system based on high-power fiber semiconductor lasers is established in the experiment. The data curve noise after passing this algorithm is smaller and the accuracy is higher, which verifies the effectiveness of the algorithm. The algorithm can be applied to the field of rapid quantitative identification and analysis of transient heat flow energy.
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V. Ioganson, Elena, Marat I. Timerzianov, Marina V. Perelman et Olga A. Kravtsova. « Reliability and Reproducibility of DNA Profiling from Degraded Samples in Forensic Genetics ». Dans Forensic Analysis [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98300.
Texte intégralRésumé :
Forensic DNA analysis is widely used to determine kinship and the identity of evidence from the crime scene and it is especially important in the identification of human remains after different types of exposure (water, heat, etc.). Currently, there are no official recommendations for forensic scientists as to which bones and tissues are the most reliable among degraded DNA samples. Since 2014 more than 350 fragments of unidentified corpses have been examined in the Forensic Biological Department (Republic Bureau of Forensic Medicine, Kazan, Russia). Based on our experience, the most reliable and reproducible DNA profiles are obtained from lower limber bones (in 90% cases), muscles (in 85% cases) and ribs (in 80% cases). However, we discovered a new source of DNA – the odontoid process of the 2nd cervical vertebra, which contains a high amount of DNA with a better state of preservation than many other bones. According to our results, when a complete skeleton or unidentified corpse is found, it is advisable to provide bones with soft tissue remnants in the absence of deeply embedded putrefactive changes. When working at the crime scene, special attention should be paid to separating small bones and fragments from skeletal remains.
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Bawa, Vanya, et Sunil Kumar Rai. « Nature of Importance of Various Parameters for Ideal Biofuel Crops : Special Reference to Rapeseed Mustard ». Dans Oilseed Crops - Biology, Production and Processing [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.107102.
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To increase the performance of diesel engine and environment, the utilization of biofuel as a major source of renewable energy is justified. It is well understood that agri-based biofuel is always also the choice in case of utilization as biofuel because of requirement of processing and threat to food security. Therefore, scope of improvement increases as it is yet to efficiently exploit as major full in the world. There are numerous factors that influence the efficiency of a fuel and its combustion. The physiochemical properties, namely viscosity, surface tension, flash point, latent heat of vaporization, oxidation, etc., allow the fuel to work efficiently during combustion. Thus, interests in biofuels have been increased, and various experimental studies have been developed for diesel engines consisting of methanol and methyl ester of rapeseed oil. In a relevant study, to achieve ideal biofuel, various biotechnological advances at the frontiers of plant science to dissect the underlying traits for identification of fatty acid profile useful for oil production and quality are essential, thereby ensuring food security. The plant-based fuel and its efficient utilization depend upon its oil quality and quantity, which thereby can be evaluated and enhanced by various conventional and nonconventional approaches of engineering and plant sciences.
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Momose, K., et H. Kimoto. « Identification of phase change interface using imaginary heat sources ». Dans Inverse Problems in Engineering Mechanics, 17–26. Elsevier, 1998. http://dx.doi.org/10.1016/b978-008043319-6/50006-6.
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Mee, Nicholas. « The Gorgon’s Head ! » Dans The Cosmic Mystery Tour, 161–66. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198831860.003.0021.
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The astronomer John Goodricke was first to realize the star Algol in the constellation Perseus regularly fades for several hours because it is periodically eclipsed by a fainter companion star. In antiquity the strange behaviour of Algol led to its mythological identification with the head of the gorgon Medusa, and this is the source of its name. Goodicke’s explanation of the variability of Algol was published in 1783. He also discovered other eclipsing binaries as well as the first Cepheid variable. Tragically, Goodricke died at the age of just 21.
Actes de conférences sur le sujet "Heat source identification"
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Lu, J. C. C., M. Q. Chen et F. T. Lin. « Modelling of Cross-Anisotropic Thermoelastic Stratum due to a Point Heat Source ». Dans Modelling, Identification, and Control. Calgary,AB,Canada : ACTAPRESS, 2010. http://dx.doi.org/10.2316/p.2010.702-084.
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Vaddi, Jyani S., et Stephen D. Holland. « Identification of heat source distribution in vibrothermography ». Dans 40TH ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION : Incorporating the 10th International Conference on Barkhausen Noise and Micromagnetic Testing. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4865020.
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Azimi, Aziz, et Ehsan Daneshgar. « Identification of Indoor Contaminant Source by Inverse Zonal Method ». Dans International Conference of Fluid Flow, Heat and Mass Transfer. Avestia Publishing, 2016. http://dx.doi.org/10.11159/ffhmt16.125.
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Chakraborty, Shubhankar, et P. K. Das. « IDENTIFICATION OF TRANSIENT INTERNAL HEAT SOURCE USING MODIFIED LEVENBERG-MARQUARDT ALGORITHM ». Dans Proceedings of the 24th National and 2nd International ISHMT-ASTFE Heat and Mass Transfer Conference (IHMTC-2017). Connecticut : Begellhouse, 2018. http://dx.doi.org/10.1615/ihmtc-2017.1390.
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ribeiro, sidney, Gabriela Oliveira et Gilmar Guimaraes. « ANALITYCAL IMPULSE RESPONSE IDENTIFICATION FOR A MOVING HEAT SOURCE PROBLEM USING GREEN’S FUNCTIONS ». Dans 25th International Congress of Mechanical Engineering. ABCM, 2019. http://dx.doi.org/10.26678/abcm.cobem2019.cob2019-1388.
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Kose, Ahmet, et Eduard Petlenkov. « Identification, implementation and simulation of Ground Source Heat Pump with ground temperature modeling ». Dans 2016 15th Biennial Baltic Electronics Conference (BEC). IEEE, 2016. http://dx.doi.org/10.1109/bec.2016.7743754.
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Yaparova, N. M., et A. D. Drozin. « Method for internal heat source identification in a rod based on indirect temperature measurements ». Dans 2017 2nd International Ural Conference on Measurements (UralCon). IEEE, 2017. http://dx.doi.org/10.1109/uralcon.2017.8120693.
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Zakaria, M. F. « Identification of Heat Source and Alteration Zone of Parangwedang Geothermal System using Magnetic Method ». Dans EAGE-HAGI 1st Asia Pacific Meeting on Near Surface Geoscience and Engineering. Netherlands : EAGE Publications BV, 2018. http://dx.doi.org/10.3997/2214-4609.201800342.
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Benard, Christine, Beatrice Guerrier et Marie-Minerve Rosset. « IDENTIFICATION OR CONTROL OF THE BOUNDARY INPUT OF A LINEAR THERMAL SYSTEM WITH NO INTRUSIVE MEASUREMENTS, IN THE PRESENCE OF INTERNAL HEAT SOURCE DISTURBANCES. » Dans International Heat Transfer Conference 8. Connecticut : Begellhouse, 1986. http://dx.doi.org/10.1615/ihtc8.330.
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Kose, Ahmet, et Eduard Petlenkov. « System identification models and using neural networks for Ground Source Heat Pump with Ground Temperature Modeling ». Dans 2016 International Joint Conference on Neural Networks (IJCNN). IEEE, 2016. http://dx.doi.org/10.1109/ijcnn.2016.7727559.
Texte intégralRapports d'organisations sur le sujet "Heat source identification"
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Cohen, Yuval, Christopher A. Cullis et Uri Lavi. Molecular Analyses of Soma-clonal Variation in Date Palm and Banana for Early Identification and Control of Off-types Generation. United States Department of Agriculture, octobre 2010. http://dx.doi.org/10.32747/2010.7592124.bard.
Texte intégralRésumé :
Date palm (Phoenix dactylifera L.) is the major fruit tree grown in arid areas in the Middle East and North Africa. In the last century, dates were introduced to new regions including the USA. Date palms are traditionally propagated through offshoots. Expansion of modern date palm groves led to the development of Tissue Culture propagation methods that generate a large number of homogenous plants, have no seasonal effect on plant source and provide tools to fight the expansion of date pests and diseases. The disadvantage of this procedure is the occurrence of off-type trees which differ from the original cultivar. In the present project we focused on two of the most common date palm off-types: (1) trees with reduced fruit setting, in which most of the flowers turn into three-carpel parthenocarpic fruits. In a severe form, multi-carpel flowers and fruitlets (with up to six or eight carpels instead of the normal three-carpel flowers) are also formed. (2) dwarf trees, having fewer and shorter leaves, very short trunk and are not bearing fruits at their expected age, compared to the normal trees. Similar off-types occur in other crop species propagated by tissue culture, like banana (mainly dwarf plants) or oil palm (with a common 'Mantled' phenotype with reduced fruit setting and occurrence of supernumerary carpels). Some off-types can only be detected several years after planting in the fields. Therefore, efficient methods for prevention of the generation of off-types, as well as methods for their detection and early removal, are required for date palms, as well as for other tissue culture propagated crops. This research is aimed at the understanding of the mechanisms by which off-types are generated, and developing markers for their early identification. Several molecular and genomic approaches were applied. Using Methylation Sensitive AFLP and bisulfite sequencing, we detected changes in DNA methylation patterns occurring in off-types. We isolated and compared the sequence and expression of candidate genes, genes related to vegetative growth and dwarfism and genes related to flower development. While no sequence variation were detected, changes in gene expression, associated with the severity of the "fruit set" phenotype were detected in two genes - PdDEF (Ortholog of rice SPW1, and AP3 B type MADS box gene), and PdDIF (a defensin gene, highly homologous to the oil palm gene EGAD). We applied transcriptomic analyses, using high throughput sequencing, to identify genes differentially expressed in the "palm heart" (the apical meristem and the region of embryonic leaves) of dwarf vs. normal trees. Among the differentially expressed genes we identified genes related to hormonal biosynthesis, perception and regulation, genes related to cell expansion, and genes related to DNA methylation. Using Representation Difference Analyses, we detected changes in the genomes of off-type trees, mainly chloroplast-derived sequences that were incorporated in the nuclear genome and sequences of transposable elements. Sequences previously identified as differing between normal and off-type trees of oil palms or banana, successfully identified variation among date palm off-types, suggesting that these represent highly labile regions of monocot genomes. The data indicate that the date palm genome, similarly to genomes of other monocot crops as oil palm and banana, is quite unstable when cells pass through a cycle of tissue culture and regeneration. Changes in DNA sequences, translocation of DNA fragments and alteration of methylation patterns occur. Consequently, patterns of gene expression are changed, resulting in abnormal phenotypes. The data can be useful for future development of tools for early identification of off-type as well as for better understanding the phenomenon of somaclonal variation during propagation in vitro.
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Kingston, A. W., O. H. Ardakani et R A Stern. Tracing the subsurface sulfur cycle using isotopic and elemental fingerprinting : from the micro to the macro scale. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329789.
Texte intégralRésumé :
Hydrogen sulfide (H2S) is a toxic and corrosive gas that commonly occurs in deeply buried sedimentary systems. Understanding its distribution is paramount to creating safe and effective models of H2S occurrence aiding in the identification of high-risk areas. Characterizing subsurface sulfur sources and H2S formation pathways would enhance these models leading to more accurate predictions of potential high H2S regions. However, gaps remain in our understanding of the dominant formation processes and migration pathways of key ingredients for H2S production in the Lower Triassic Montney Formation of the Western Canada Sedimentary Basin (WCSB). Essential to this is assessing the reactants necessary for H2S production, potential pathways for fluid migration, diagenetic history, and changes in redox conditions through time. The Montney Formation has undergone several phases of diagenesis related to post-depositional alteration and multiple cycles of tectonic burial and uplift. Early chemical alteration includes dolomitization and, in some cases, microbial reduction of porewater sulfate to sulfide that occurred prior to significant burial (Davies et al., 1997; Vaisblat et al., 2021; Liseroudi et al., 2020, 2021). The most recent tectonic-related burial during the Laramide Orogeny resulted in burial depths in excess of 3-5 km (Ness, 2001; Ducros et al., 2017) leading to significant thermal and barometric alteration. Associated with this orogenic activity was the reactivation of underlying faults (O'Connell et al., 1990) and development of fractures especially near the deformation front. These fractures provide conduits for fluid migration into the Montney that combined with heat and pressure resulting in hydrocarbon generation, migration, and development of overpressure, notably in the western margin of the basin. In addition, high temperatures resulted in thermochemical sulfate reduction (TSR) leading to the formation of H2S and subsequently pyrite. We present an interpretation of the Montney subsurface sulfur cycle through the use of petrography, micro- and macro-scale geochemical analysis (isotopic and elemental) to illustrate the complexity of this system. This work relies heavily on previous studies within and outside our research group and incorporates new analytical techniques to expand the toolbox. We aim to guide future research directions and activities by addressing issues related to sampling and data quality issues, analytical approaches, and highlight knowledge gaps.
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O'Connell, Kelly, David Burdick, Melissa Vaccarino, Colin Lock, Greg Zimmerman et Yakuta Bhagat. Coral species inventory at War in the Pacific National Historical Park : Final report. National Park Service, 2024. http://dx.doi.org/10.36967/2302040.
Texte intégralRésumé :
The War in the Pacific National Historical Park (WAPA), a protected area managed by the National Park Service (NPS), was established "to commemorate the bravery and sacrifice of those participating in the campaigns of the Pacific Theater of World War II and to conserve and interpret outstanding natural, scenic, and historic values on the island of Guam." Coral reef systems present in the park represent a vital element of Guam?s cultural, traditional, and economical heritage, and as such, are precious and in need of conservation. To facilitate the management of these resources, NPS determined that a scleractinian (stony coral) species survey was necessary to establish a baseline for existing coral communities and other important factors for conservation. EnviroScience, Inc. performed a survey of stony coral species, coral habitat, and current evidence of stressors at WAPA?s H?gat and Asan Units in 2022. This report summarizes these findings from a management perspective and compares its findings to previous survey data from 1977 and 1999 (Eldridge et al. 1977; Amesbury et al. 1999). WAPA is located on the tropical island of Guam, located on the west-central coast of the island, and encompasses 2,037 acres. Underwater resources are a significant component of the park, as 1,002 acres consists of water acres. The park is comprised of seven units, of which two of these, the H?gat and Asan Beach Units, include all the oceanic water acres for the park. The H?gat Beach Unit (local spelling, formerly known as ?Agat?) is located at the south-west portion of the park and consists of 38 land acres and 557 water acres (NPS 2003). The Asan Beach Unit consists of 109 acres of land and 445 water acres (NPS 2003). A current baseline for existing coral communities and other important factors for conservation necessitates the need for up-to-date data on the location, presence, relative abundance, and present health of corals. Park managers need this updated data to determine where and how to best focus conservation priorities and identify restoration opportunities. Management actions in park reef areas informed by this inventory included identifying locations where there were: high rates of sedimentation; high coral biomass; rare or threatened species, with a priority given to species endemic to Guam and listed as ?threatened? under the U.S. Endangered Species Act (ESA; Acropora globiceps, A. retusa, A. speciosa, and Seriatopora aculeata); coral persistence and decline, disease and/or nuisance species, including the crown-of-thorns starfish (Acanthaster cf. solaris, ?COTS?) and the sponge Terpios hoshinota; and bleached areas. All work carried out was in accordance with the NPS statement of work (SOW) requirements, which involved a quantitative inventory using both new and pre-existing transects. The resulting transects totaled 61 (including the four from the 1999 study), each measuring 50 meters in length and distributed across depths of up to 50 feet. Divers took photo-quadrat samples covering an area of approximately 9 m?, encompassing 50 photo-quadrats of dimensions 0.50 m x 0.36 m (n=50). The collective area surveyed across all 61 transects amounted to ~549 m?. Additionally, a qualitative search was conducted to enhance documentation of coral species that have limited distribution and might not be captured by transects, along with identifying harmful species and stressors. Timed roving diver coral diversity surveys were carried out at a total of 20 sites occurring within the waters of WAPA, including eight sites at the H?gat unit and 12 sites at the Asan unit. The findings from this report reveal significant disparities in benthic cover compositions between H?gat and Asan units. The H?gat unit exhibits high abundances of turf algae and unconsolidated sediment while the Asan beach unit presents a different scenario, with hard coral as the dominant benthic cover, followed closely by crustose coralline algae (CCA). The Asan unit is also more difficult to access from shore or boat relative to H?gat which provides that unit some protection from human influences. The Asan beach unit's prevalence of hard coral, CCA, and colonizable substrate suggests a more favorable environment for reef growth and the potential benefits of maintaining robust coral cover in the area. These distinct differences in benthic communities highlight the contrasting ecological dynamics and habitats of the two study areas. Across both H?gat and Asan beach unit transects, a total of 56 hard coral species were recorded from 27 genera, with 44 species recorded from the H?gat unit and 48 species recorded from the Asan unit. Of the four historical transects surveyed in the Asan unit from 1999, three experienced declines in percent coral cover (17.38-78.72%), while the fourth had an increase (10.98%). During the timed roving diver coral diversity surveys, a total of 245 hard coral species, including 241 scleractinian coral species representing 49 genera and 4 non-scleractinian coral species representing 4 genera were recorded. Uncertainties related to coral identification, unresolved boundaries between morphospecies, differences in taxonomists' perspectives, and the rapidly evolving state of coral taxonomy have significant implications for species determinations during coral diversity surveys. While the recent surveys have provided valuable insights into coral diversity in WAPA waters, ongoing taxonomic research and collaboration among experts will be essential to obtain a more comprehensive and accurate understanding of coral biodiversity in the region. Of the several ESA coral species that were searched for among the H?gat and Asan beach units, Acropora retusa was the only coral species found among quantitative transects (n=2) and A. globiceps was observed during coral diversity surveys. Acropora speciosa, which was dominant in the upper seaward slopes in 1977, is now conspicuously absent from all the surveys conducted in 2022 (Eldredge et al., 1977). The disappearance and reduction of these once-dominant species underscores the urgency of implementing conservation measures to safeguard the delicate balance of Guam's coral reefs and preserve the diversity and ecological integrity of these invaluable marine ecosystems. Other formerly common or locally abundant species were infrequently encountered during the diversity surveys, including Acropora monticulosa, A. sp. ?obtusicaulis?, A. palmerae, Stylophora sp. ?mordax?, Montipora sp. ?pagoensis?, and Millepora dichotoma. Significant bleaching-associated mortality was recorded for these species, most of which are restricted to reef front/margin zones exposed to moderate-to-high levels of wave energy. Sedimentation was present in both H?gat and the Asan units, though it was more commonly encountered in H?gat transects. While significant portions of the reef area within the WAPA H?gat unit are in poor condition due to a variety of stressors, some areas still hosted notable coral communities, which should be a potential focus for park management to prevent further degradation. There is a need for more effective management of point source pollution concerns, particularly when subpar wastewater treatment or runoff from areas with potential pollution or sediment-laden water is flowing from nearby terrestrial environments. Future monitoring efforts should aim to establish a framework that facilitates a deeper understanding of potential point source pollution incidents. This would empower park managers to collaborate with adjacent communities, both within and outside of park boundaries, to mitigate the localized impacts of pollution (McCutcheon and McKenna, 2021). COTS were encountered during transect surveys as well as in coral diversity surveys. including along the upper reef front/reef margin at site Agat-CS-2. The frequency of these observations, particularly in the WAPA H?gat unit and where stress-susceptible corals are already uncommonly encountered, raise concern about the ability of the populations of these coral species to recover following acute disturbance events, and calls in to question the ability of some of these species to persist in WAPA waters, and in Guam?s waters more broadly. More frequent crown-of-thorns control efforts, even if only a handful of sea stars are removed during a single effort, may be required to prevent further loss to vulnerable species. There were several documented incidents of Terpios hoshinota covering large sections of branching coral in the reef flat along transects, but it is still unclear how detrimental this sponge is to the overall reef system. There is a concern that elevated levels of organic matter and nutrients in the water, such as those resulting from sewage discharge or stormwater runoff, could lead to increased Terpios populations (De Voogd et al. 2013). Consequently, it is important to track populations in known areas of sedimentation and poor water quality. The presence of unique species at single survey sites within the study areas underscores the ecological importance of certain locations. Some species are known to occur in other locations in Guam, while a few may be limited to specific sites within WAPA waters. These differences are likely influenced by environmental and biological factors such as poor water quality, severe heat stress events, chronic predation by crown-of-thorns sea stars, disease, and reduced herbivore populations. These factors collectively shape the condition of the benthic community, leading to variations in species distribution and abundance across the study sites. Documenting coral stress and identifying potentially harmful species allows for proactive management strategies to prevent the establishment of nuisance or detrimental species while populations are still manageable. Updated data on the location, presence, relative abundance, and health of corals is essential for park managers to prioritize conservation efforts and identify restoration opportunities effectively. Observations from this report raise concerns about the health and resilience of coral ecosystems in the H?gat unit and emphasize the need for knowledge of local factors that shape benthic community structure. Understanding the drivers responsible for these variations is crucial for effective conservation and management strategies to preserve the ecological balance and overall health of coral reefs in both units. Continued monitoring efforts will be critical in assessing long-term trends and changes in benthic cover and enabling adaptive management approaches to safeguard these valuable marine ecosystems in the face of ongoing environmental challenges.