Dissertations / Theses: 'Temperature method'

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Karadag, Rukiye. "Temperature Distribution In Power Transformers." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615162/index.pdf.

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As in all other electrical equipments it is essential to estimate the temperature distribution in transformer components in the design stage and during the operation since temperatures above thermal limits of these components might seriously damage them. Thermal models are used to predict this vital information prior to actual operations. In this study, a three dimensional model based on the Finite Element Method (FEM) is proposed to estimate the temperature distribution in the three phase, SF6 gas insulated-cooled power transformer. This model can predict the temperature distribution at the specific discredited locations in the transformer successfully.

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McAughey, Kevin. "Fabrication of high temperature piezoelectric ceramics by sol gel method." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/55918/.

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This research covers the fabrication of piezoelectric ceramics using a sol gel method. Commercial high temperature transducers are typically fabricated by a milled oxide method. The sol gel method presented here produced purer samples that can be prepared at lower temperatures than conventional milled oxide preparations. The performance of the samples as piezoelectric transducers was also investigated, with the samples produced by sol gel method exceeding the piezoelectric response of the commercial samples.

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Yu, Shuang. ""Small tip angle" method NMR studies of high temperature superconductors /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488203857251481.

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Amoah-Kusi, Christian. "Constant Interface Temperature Reliability Assessment Method: An Alternative Method for Testing Thermal Interface Material in Products." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2295.

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As electronic packages and their thermal solutions become more complex the reliability margins in the thermal solutions diminish and become less tolerant to errors in reliability predictions. The current method of thermally stress testing thermal solutions can be over or under predicting end of life thermal performance. Benefits of accurate testing and modeling are improved silicon yield in manufacturing, improved performance, lower cost thermal solutions, and shortened test times. The current method of thermally stress testing is to place the entire unit in an elevated isothermal temperature and periodically measure thermal performance. Isothermally aging is not an accurate representation of how the unit will be used by the customer and does not capture the thermal gradients and mechanical stresses due to different coefficients of thermal expansion of the materials used in the thermal solution. A new testing system, CITRAM which is an acronym for Constant Interface Temperature Reliability Method, has been developed that uses an electronic test board. The approach captures the thermal and mechanical stresses accurately and improves test time by 20-30% as a result of automation. Through this study a difference in the two methods has been identified and the new CITRAM method should be adopted as current practice.

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Huang, Huai Hui. "Simulação da formação de cavacos usando FEM (Finite Element Method) - temperatura e força." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18145/tde-11122007-162007/.

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A distribuição de temperatura, as deformações e as forças na zona de corte durante a formação de cavacos são muito importantes, pois têm grande influência nos resultados dos processos de usinagem como um todo. O desgaste das ferramentas, a precisão das operações de usinagem (dilatação térmica) e o acabamento superficial são alguns desses resultados que afetam a economia do processo. Este trabalho tem o objetivo uma avaliação das potencialidades oferecidas pela simulação da formação de cavacos usando-se FEM (Finite Element Method). Quatros modelos com princípios bastante diferentes são utilizados explorando-se as mais recentes inovações em termos de recursos oferecidos pelo software ABAQUS/Explicit. Nos modelos utilizam-se ferramentas de substrato WC recoberto com TiN usinado aços AISI 4340. As simulações proporcionam o estudo e exame detalhado da distribuição de temperatura, deformações, forças de corte, fluxo de material e uma enorme quantidade de informações que poderão ser muito úteis para a análise de novos processos, otimização de processos existentes, além de abrir novos horizontes no estudo da formação de cavacos. As simulações também demonstram que a complexidade da formação de cavacos cria muitas dificuldades para sua análise usando equações analíticas baseadas em constantes.
The distribution of temperature, the deformations and the cutting forces in the cutting zone during chip formation are very important aspects of the process. Therefore they have great influence in results of machining. Tool wear, the precision of the machining operations and the finishing superface are some of these results that affect the economy of the process. This work has the objective of an evaluation offered potentialities for simulating chip formation using FEM (Finite Element Method). Four models with sufficiently different principles are used to exploring the most recent innovations in terms of resources offered by ABAQUS/Explicit software. In the models, WC tools coated TiN was used to machine AISI 4340 steel. The simulations provide a study and detailed examination of temperature distribution, deformations, cutting forces, flow of material and an enormous amount of information that could be useful for the analysis of new processes and optimization of existing processes. Additionally, they open new horizon in the study of the chip formation. The simulations also demonstrate the complexity of the chip formation process, which creates many difficulties for its analysis using based analytical equations in constants. Some comparisons are established with experimental results found in temperature measurements.

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Yang, Weixuan. "Temperature-dependent homogenization technique and nanoscale meshfree particle methods." Diss., University of Iowa, 2007. http://ir.uiowa.edu/etd/147.

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KARKI, BHISHMA R. "SURFACE RESISTANCE OF HIGH TEMPERATURE SUPERCONDUCTOR BY THE RESONANT CAVITY METHOD." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1084380437.

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Lydiate, Joseph. "A novel method of biosensing using a temperature invariant microring resonator." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/a-novel-method-of-biosensing-using-a-temperature-invariant-microring-resonator(3e692f11-d045-4e75-a7c4-88a7df830186).html.

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In this thesis, simulations of two novel features of a serially cascaded micro-ring resonator are presented. The thesis firstly describes the simulation of a novel, silicon on insulator (SOI) method to determine the refractive index change of a covering analyte by the extraction of the refractive index change information in the time domain. Secondly a novel arrangement of the serially cascaded micro-rings has the effect of producing a null instead of a peak in the Vernier enhanced resonant spectrum. The null feature, as well as the enhanced sensitivity of the sensor, allows the sensor to be used as an intensity interrogating device. The development of these applications using ring resonator physics is achievable, out-of-lab, by the application of photonic software. Finite difference time domain (FDTD), beam propagation method (BPM), finite element(FE) and eigenmode expansion (EME) methods were all used in the simulated development of the sensor. As a result of the dual ring resonator arrangement, the temporal output undergoes a wavelength (or frequency) shift from the micrometre (or TeraHertz) to the centimeter (or GigaHertz) range of frequencies. This allows the refractive index information to become available for transmission in the cm wavelength range over a standard wireless network. The latter could be realized by integration of a photo-detector and antenna into the final design. The sensor output is invariant to any structural or temperature changes applied to both rings. Two sensors based on the same design, but having different fabrication methods, are simulated. Models of the rib and ridge structures are realized by using optical simulation software. The data obtained from these simulations are then used to plot the ring resonator outputs in MATLAB. The design can be applied for either bulk (homogeneous) or surface sensing. Only homogeneous sensing, in the form of a uniform refractive index cover change, is simulated in this thesis. The spectral sensitivity of the rib based design, without Vernier enhancement, is 87.65nmRIU-1, while the spectral sensitivity of the ridge waveguide, without Vernier enhancement, is 422nmRIU-1. The Vernier enhanced spectral sensitivity of the rib design is 6415nmRIU-1 and the limit of detection is 12.47x10-6 RIU. The temporal sensitivity of the ridge is 1.9418μsec RIU-1. The rib temporal sensitivity was not calculated but it is expected to be ~ five times less sensitive than the non Vernier enhanced ridge design. Titanium Nitride (TiN) heaters were also included over the coupling regions of the dual ring resonators. The effect of the heaters on the dual ring resonant wavelength and on the single ring spectral shift were also simulated using a multi-physics utility of the applied FEM and BPM software. With the heater at 1.28μm above the resonator coupling waveguides, a single ring spectral shift of 717pm was exhibited by this simulation. For the heater positioned at 250nm above the coupling waveguides, a single ring spectral shift of 2.89nm was exhibited. Finally the fabricated designs, which are based on the models of the simulation data, were characterized and the results compared to the predicted outputs generated by the models of the Temperature Invariant Modulated Output Sensor (TIMOS).

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9

James, Gareth Christopher. "Frequency domain temperature model : a new method in on-line temperature estimation for power modules in drives applications." Thesis, University of Newcastle upon Tyne, 2011. http://hdl.handle.net/10443/2260.

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The operating temperature of the components within an electronic device has a significant impact on the reliability of a product. In a variable speed drive the power semiconductors in the inverter stage are often operated close to their maximum temperature when the inverter is operating at a low output frequency or during an overload. The temperature of these components must be continuously monitored to prevent them from overheating, but direct measurement of the temperature is only possible if a special test configuration can be used. This is not practicable in a commercial drive and to protect the inverter the temperature of the power semiconductors must be estimated by an on-line thermal model. The work presented in this thesis describes the development of a novel thermal model that can be implemented using the existing computational resources available in a commercial variable speed drive. The thermal model is based on the transient thermal impedance measured between each device and the internal thermistor in a power module. These form a thermal impedance matrix which can be used to calculate the instantaneous temperature of every device in the inverter. However, with the existing computational resources it is not possible to implement the complete matrix without aliasing. To reduce the risk of aliasing the number of calculations performed during each sample period must be reduced. This is achieved by using a frequency domain model that has been developed to calculate the peak temperature of the hottest devices. To validate the thermal model it has been implemented in a commercial drive. The drive has been modified to allow the temperature of the power semiconductors in the inverter to be measured using a high speed thermal camera. This allows the temperature estimated by the on-line thermal model to be compared directly with the temperatures measured when the inverter is operating under typical load conditions. Comparisons of the measured and estimated temperatures in several operating conditions are presented. These conditions were chosen to highlight the advantages and disadvantages of the frequency domain model.

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10

Zhang, Hui. "Influence of High Temperature Creep upon the Structure of ß-NiAl and ß-NiAl(Fe) Single Crystals." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2002. http://nbn-resolving.de/urn:nbn:de:swb:14-1038216865812-53920.

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The principal aim of this thesis is to characterise quantitatively the influence of high temperature creep upon the structure of ß-NiAl and ß-NiAl(Fe) single crystals. A non-destructive procedure is established following the classic line of X-ray structure analysis, namely controlling the chemical composition with the electron probe microanalysis, determining the unit cell contents from the combined lattice parameter and mass density measurements, and refining the structure parameters according to the X-ray reflection intensity. Specifically, two special single crystal X-ray diffraction methods, namely the back reflection Kossel technique and the back reflection Laue method, are applied for the determination of lattice parameter and for the collection of intensity data. All experimental measurements can be performed in non-destructive manner, which allows a direct comparison to be made between the crystal structure determined prior to and after a creep test.

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Arkan, Serkan. "Assessment Of Low Temperature Geothermal Resources." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/2/1122662/index.pdf.

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One of the most applicable methods of low-temperature geothermal resource assessment is volumetric method. While applying volumetric method, the values of uncertain parameters should be determined. An add-in software program to Microsoft EXCEL, @RISK, is used as a tool to define the uncertainties of the parameters in volumetric equation. In this study, Monte Carlo simulation technique is used as the probabilistic approach for the assessment of lowtemperature Balç
ova-Narlidere geothermal field. Although Balç
ova-Narlidere geothermal field is being utilized for several direct heat applications, there exists limited data for resource assessment calculations. Assessment studies using triangular and uniform distribution type functions for each parameter gave the mean values of recoverable heat energy of the field as 25.1 MWt and 27.6 MWt, respectively. As optimistic values (90%), those values were found as 43.6 MWt and 54.3 MWt. While calculating these numbers, a project life of 25 years with a load factor of 50% is used.

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12

Javid, Shahid. "Residual effect of phosphate fertiliser measured using the Olsen method in Pakistani soils." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342535.

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Sawatdiaree, Sivinee. "Thermodynamics of the fractional quantum hall system the high-temperature expansion method /." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962738336.

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14

Chen, Yulong. "A combinatorial method for discovery of BaTiO3-based positive temperature coefficient resistors." Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/435.

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The conventional materials discovery is a kind of empirical (“trial and error”) science that of handling one sample at a time in the processes of synthesis and characterization. However, combinatorial methodologies present the possibility of a vastly increased rate of discovery of novel materials which will require a great deal of conventional laboratory work. The work presented in this thesis, involved the practice of a conceptual framework of combinatorial research on BaTiO3-based positive temperature coefficient resistor (PTCR) materials. Those including (i) fabrication of green BaTiO3 base discs via high-throughput dip-pen printing method. Preparation and formulation of BaTiO3 inks (selection of dispersant and binder/volume fraction) were studied. The shape of drying residues and the morphogenesis control of droplet drying were discussed. (ii) investigation of a fast droplet-doping method, which induced the dopant precursor solution infiltrating into the porous BT base disc. Various characterization methods were used to examine the dopant distribution in the body of disc. (iii) devising a high-throughput electrical measurement system including an integrated unit of temperature control and automatic measurement operation, and an arrayed multichannel jig. (iv) synthesis of donor-doped BaTiO3 libraries, which involved lanthanum, erbium, yttrium as donor elements and manganese as an acceptor dopant element respectively. Their temperature dependant resistivities were also explored. The work successfully developed an integrated tool including high-throughput synthesis of a large batch of libraries and high-throughput electrical property measurement for combinatorial research on BaTiO3-based PTCR ceramics. The Abstract ii combinatorial method, thus validated, has the potential to deliver dopant-doped BTbased PTCR libraries rapidly with a very wide range of dopant mixtures and concentrations for electrical property measurement and deserves to be applied to other low level dopant ceramic systems. These approaches are novel and paving the way for other new materials selection and materials research.

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15

Zhao, Xing. "CURIE TEMPERATURE MEASUREMENT OF FERROMAGNETIC NANOPARTICLES BY USING CALORIMETRY." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1421085560.

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Andrienko, Daniil. "Non-equilibrium Models for High Temperature Gas Flows." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1405505300.

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Cai, Xiao. "An Analytical Method for Predicting Wellbore Temperature Profile During Drilling Gas Hydrates Reservoirs." Thesis, University of Louisiana at Lafayette, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10163276.

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Production of natural gas from unconventional gas-hydrate reservoirs faces kinds of challenges and uncertainties. One of the main and most common problems in gas-hydrates drilling is the dissociated gas from gas hydrates with decrease of pressure, increase of temperature, or combination of them. A reliable method that can be applied to predict the temperature profile of fluid during circulating in the drilling pipe and the annulus is needed. An analytical model was developed in this study for predicting temperature profiles in drilling gas-hydrate deposits. A case study is provided and indicates a good consistency between model-implications and field observations. According to the sensitivity analyses, the temperature profile of fluid in the drill pipe can be affected by the thickness of drill pipe, density and heat capacity of drill mud, pumping rate of drill mud, geo-thermal gradient, and the surface geo-temperature. The bottom hole temperature is dominated by the temperature and flow rate of the injected drilling fluid, thermal conductivity of cement, heat capacity and density of drill mud, geo-thermal gradient and geothermal temperature at surface, thickness of drill pipe, and cement sheath. Higher geothermal gradient and surface geothermal temperature can lead to a higher temperature profile of fluid in the annulus. The Joule-Thomason cooling effect below the drill bit nozzles will rapidly diminish in a short interval above the bottom hole by the heating effect of geo-thermal gradient. The rate of penetration of drill bit has negligible effect on the fluid temperature profile due to the low percentage of heat flow contributed by the drill cuttings.

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MacKay, James D. "Analytical method for turbine blade temperature mapping to estimate a pyrometer input signal." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45797.

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The purpose of this thesis is to develop a method to estimate local blade temperatures in a gas turbine for comparison with the output signal of an experimental pyrometer. The goal of the method is to provide a temperature measurement benchmark based on a knowledge of blade geometry and engine operating conditions. A survey of currently available methods is discussed including both experimental and analytical techniques.The purpose of this thesis is to develop a method to estimate local blade temperatures in a gas turbine for comparison with the output signal of an experimental pyrometer. The goal of the method is to provide a temperature measurement benchmark based on a knowledge of blade geometry and engine operating conditions. A survey of currently available methods is discussed including both experimental and analytical techniques.

An analytical approach is presented as an example, using the output from a cascade flow solver to estimate local blade temperatures from local flow conditions. With the local blade temperatures, a grid is constructed which maps the temperatures onto the blade. A predicted pyrometer trace path is then used to interpolate temperature values from the grid, predicting the temperature history a pyrometer would record as the blade rotates through the pyrometer line of sight. Plotting the temperature history models a pyrometer input signal. An analytical approach is presented as an example, using the output from a cascade flow solver to estimate local blade temperatures from local flow conditions. With the local blade temperatures, a grid is constructed which maps the temperatures onto the blade. A predicted pyrometer trace path is then used to interpolate temperature values from the grid, predicting the temperature history a pyrometer would record as the blade rotates through the pyrometer line of sight. Plotting the temperature history models a pyrometer input signal.

Master of Science

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19

Jarboe, Jason Neal. "A method for infrared temperature measurements of thin film materials with a low, unknown, and/or variable emissivity at low temperatures." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/84401.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Accurate non-contact temperature measurements of objects using thermal radiation is often limited by low emission of IR radiation because of low temperatures and/or emissivities, or by the unknown or changing emissivity of the material being measured. This thesis covers an effort to build a practical, inexpensive, and widely applicable non-contact system for accurately measuring the temperatures of materials of low, unknown, and/or variable emissivity. The method to be used is intended specifically for those objects at low temperatures (below 100 degrees Celsius), which are conventionally the most difficult to accurately measure.
by Jason Neal Jarboe.
S.B.

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20

Petla, Harita. "Computational design of ultra-high temperature ceramic composite materials." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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21

Salomonsson, Stefan. "Simulation of Temperature Distribution in IR Camera Chip." Thesis, Linköpings universitet, Informationskodning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-65830.

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The thesis investigates the temperature distribution in the chip of an infrared camera caused by its read out integrated circuit. The heat from the read out circuits can cause distortions to the thermal image. Knowing the temperature gradient caused by internal heating, it will later be possible to correct the image by implementing algorithms subtracting temperature contribution from the read out integrated circuit. The simulated temperature distribution shows a temperature gradient along the edges of the matrix of active bolometers. There are also three hot spots at both the left and right edge of the matrix, caused by heat from the chip temperaturesensors and I/O pads. Heat from the chip temperature sensors also causes an uneven temperature profile in the column of reference pixels, possibly causing imperfections in the image at the levels of the sensors. Simulations of bolometer row biasing are carried out to get information about how biasing affects temperatures in neighbouring rows. The simulations show some row-to-row interference, but the thermal model suffers from having biasing heat inserted directly onto the top surface of the chip, as opposed to having heat originate from the bolometers. To get better simulation results describing the row biasing, a thermal model of the bolometers needs to be included. The results indicate a very small temperature increase in the active pixel array, with temperatures not exceeding ten millikelvin. Through comparisons with another similar simulation of the chip, there is reason to believe the simulated temperature increase is a bit low. The other simulation cannot be used to draw any conclusions about the distribution of temperature.
Examensarbetet undersöker den temperaturdistribution som uppkommer i ett chip till en IR-kamera till följd av värmeutvecklingen i dess egna utläsningskretsar. Genom att ha information om temperaturdistributionen är det möjligt att längre fram i utvecklingsprocessen skapa algoritmer som subtraherar bort chippets interna värmetillskott från den termiska bilden. Den simulerade temperaturdistributionen visar att de största temperaturgradienterna uppkommer längs den aktiva pixelmatrisens sidor. Det är även möjligt att se tre varmare områden vid både den vänstra och högra sidan av matrisen skapade av värme från chippets temperatursensorer och I/O-kretsar. Värme från temperatursensorerna påverkar även temperaturen i kolumnen med referenspixlar, vilket kan ge upphov till avvikelser i den termiska bilden i höjd med dessa temperatursensorer. Simuleringar av radvis basering av bolometrar utförs för att få information om hur bolometerbiaseringen påverkar temperaturen i angränsade rader. Simuleringarna visar att det finns störningar mellan rader, men simuleringsmodellen lider av avsaknaden av en termisk bolometermodell och tvingas applicera värme direkt på chipytan istället för att låta värme utvecklas i bolometrarna. För bättre simuleringsresultat innefattande bolometerbiasering bör en termisk bolometermodell inkluderas i simuleringen. Resultaten visar på en mycket liten temperaturökning inom den värmekänsliga aktiva pixelmatrisen, med temperaturökningar inom detta område som inte överstiger tio millikelvin. Genom jämförelser med en liknande simulering av samma chip är det inte omöjligt att dra slutsatsen att temperaturökningen är något låg. Det går inte att dra några slutsatser om temperaturens distribution genom denna jämförelse av simuleringar.

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Böjeryd, Jesper. "Long Time Integration of Molecular Dynamics at Constant Temperature with the Symplectic Euler Method." Thesis, KTH, Numerisk analys, NA, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-165324.

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Simulations of particle systems at constant temperature may be used to estimate several of the system’s physical properties, and some require integration over very long time to be accurate. To achieve sufficient accuracy in finite time the choice of numerical scheme is important and we suggest to use the symplectic Euler method combined with a step in an Ornstein-Uhlenbeck process. This scheme is computationally very cheap and is often used in applications of molecular dynamics. This thesis strives to motivate the usage of the scheme due to the lack of theoretical results and comparisons to alternative methods. We conduct three numerical experiments to evaluate the scheme. The design of each experiment aims to expose weaknesses or strengths of the method. For both model problems and more realistic experiments are the results positive in favor of the method; the symplectic Euler method combined with an Ornstein- Uhlenbeck step does perform well over long times.
Simuleringar av partikelsystem vid konstant temperatur kan användas för att uppskatta flera av systemets fysiska egenskaper. Vissa klasser av egenskaper kräver integration över väldigt lång tid för att uppnå hög noggrannhet och för att uppnå detta i ändlig tid är valet av numerisk metod viktigt. Vi föreslår att använda den symplektiska Euler-metoden i kombination med ett implicit steg i en Ornstein-Uhlenbeck-process. Detta stegschema kräver låg beräkning jämfört med andra scheman och används redan i olika applikationer av molekyldynamik. Detta examensarbete eftersträvar att än mer motivera användandet av schemat, eftersom teoretiska resultat som stödjer metoder är få, och avsaknaden av tidigare liknande studier är betydlig. Vi genomför tre numeriska experiment för att pröva schemat. Under utformningen av experimenten har vi försökt att inkorporera olika fenomen som kan orsaka svårigheter för metoden för att exponera svagheter eller styrkor hos den. För båda modellproblem och för ett mer realistiskt experiment är resultaten positiva till schemats fördel; metoden att kombinera ett symplektisk Euler-steg med ett steg i Ornstein-Uhlenbeck-processen presterar bra över lång tid.

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23

Strapko, Jaroslav. "Měření teplotních profilů SMD pouzder." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218369.

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Diploma thesis mainly deals with temperature management and calculation of temperature profile in oven by using SMD packages (PLCC, 1206) of different thermal capacitance on testing PCB. Above all shows theoretical consecution of temperature profile calculation in oven by using known mathematical method like the lumped capacitance method or finite difference method. Theoretical solution and measured values are compared. Diploma thesis also deals with fixation methods of thermocouples K type on assembly, comparison methods based on known and subexperiment, determines the deficiencies of methods. This thesis can perform as theoretical as well as experimental resource to prediction of temperature profiles of PCB´s with different assembly density.

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Lasley, Mark Jason. "A finite element simulation of temperature and material flow in fricton stir welding /." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd642.pdf.

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Bezuidenhout, Johannes Jurie. "Convective heat flux determination using surface temperature history measurements and an inverse calculation method." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/35706.

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Effective gages to measure skin friction and heat transfer have been established over decades. One of the most important criteria in designing such a gage is the physical size of the gage to minimise the interference of the flow, as well as the mass of these devices. The combined measurement of skin friction and heat flux using one single gage on the other hand, present unique opportunities and with it, unique technical problems.

The objective of this study is therefore to develop a cost-effective single gage that can be used to measure both skin friction and heat flux. The method proposed in this study is to install a coaxial thermocouple into an existing skin friction gage to measure the unsteady temperature on the surface of the gage. By using the temperature history and a computer program the heat flux through the surface can be obtained through an iterative guessing method. To ensure that the heat flux through the gage is similar to the heat flux through the rest of the surface, the gage is manufactured of a material very similar to the rest of the surface.

Walker developed a computer program capable of predicting the heat flux through a surface from the measured surface temperature history. The program is based on an inverse approach to calculate the heat flux through the surface. The biggest advantages of this method are its stability and the small amount of noise induced into the system. The drawback of the method is that it is limited to semi-infinite objects. For surfaces with a finite thickness, a second thermocouple was installed into the system some distance below the first thermocouple. By modifying the computer program these two unsteady temperatures can be used to predict the heat flux through a surface of finite thickness.

As part of this study, the effect of noise induced by the Cook-Felderman technique, found in the literature were investigated in detail and it was concluded that the method proposed in this study is superior to this Cook-Felderman method. Heat flux measurements compared well with measurements recorded with heat flux gages. In all cases evaluated the difference was less than 20%. It can therefore be concluded that heat flux gages on their own can measure surface heat flux very accurately. These gages are however too large to install in a skin-friction gage. The method introduced in this study is noisier than the heat flux gages on their own, but the size which is very important, is magnitudes smaller when using a coaxial thermocouple, to measure the surface temperature history.
Master of Science

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Gozcu, Ferhat Can. "Estimation Of Steady-state Temperature Distribution In Power Transformer By Using Finite Difference Method." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611592/index.pdf.

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Estimating the temperature distribution in transformer components in the design stage and during the operation is crucial since temperatures above the thermal limits of these components might seriously damage them. Thermal models are used to predict this vital information prior to actual operations. In this study, a two-dimensional, steady-state model based on the Finite Difference Method (FDM) is proposed to estimate the temperature distribution in the three-phase, SF6 gas insulatedcooled power transformer. The model can predict the temperature distribution at the specific discredited locations in the transformer successfully. This study also compares predicted temperatures of the model proposed in this study with the results of the previous study which is based on Finite Element Method (FEM) and the results of the research performed by the designers of the transformer. The results show that FDM model proposed in this study can be used to estimate the temperature distribution in the transformer with an acceptable accuracy and can be an alternative of the previous study which is based on FEM.

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Mih, Thomas Attia. "A novel low-temperature growth method of silicon structures and application in flash memory." Thesis, De Montfort University, 2011. http://hdl.handle.net/2086/5183.

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Flash memories are solid-state non-volatile memories. They play a vital role especially in information storage in a wide range of consumer electronic devices and applications including smart phones, digital cameras, laptop computers, and satellite navigators. The demand for high density flash has surged as a result of the proliferation of these consumer electronic portable gadgets and the more features they offer – wireless internet, touch screen, video capabilities. The increase in the density of flash memory devices over the years has come as a result of continuous memory cell-size reduction. This size scaling is however approaching a dead end and it is widely agreed that further reduction beyond the 20 nm technological node is going to be very difficult, as it would result to challenges such as cross-talk or cell-to-cell interference, a high statistical variation in the number of stored electrons in the floating gate and high leakage currents due to thinner tunnel oxides. Because of these challenges a wide range of solutions in form of materials and device architectures are being investigated. Among them is three-dimensional (3-D) flash, which is widely acclaimed as the ideal solution, as they promise the integration of long-time retention and ultra-high density cells without compromising device reliability. However, current high temperature (>600 °C) growth techniques of the Polycrystalline silicon floating gate material are incompatible with 3-D flash memory; with vertically stacked memory layers, which require process temperatures to be ≤ 400 °C. There already exist some low temperature techniques for producing polycrystalline silicon such as laser annealing, solid-phase crystallization of amorphous silicon and metal-induced crystallization. However, these have some short-comings which make them not suitable for use in 3-D flash memory, e.g. the high furnace annealing temperatures (700 °C) in solid-phase crystallization of amorphous silicon which could potentially damage underlying memory layers in 3-D flash, and the metal contaminants in metal-induced crystallization which is a potential source of high leakage currents. There is therefore a need for alternative low temperature techniques that would be most suitable for flash memory purposes. With reference to the above, the main objective of this research was to develop a novel low temperature method for growing silicon structures at ≤ 400 °C. This thesis thus describes the development of a low-temperature method for polycrystalline silicon growth and the application of the technique in a capacitor-like flash memory device. It has been demonstrated that silicon structures with polycrystalline silicon-like properties can be grown at ≤ 400 °C in a 13.56 MHz radio frequency (RF) plasma-enhanced chemical vapour deposition (PECVD) reactor with the aid of Nickel Formate Dihydrate (NFD). It is also shown that the NFD coated on the substrates, thermally decomposes in-situ during the deposition process forming Ni particles that act as nucleation and growth sites of polycrystalline silicon. Silicon films grown by this technique and without annealing, have exhibited optical band gaps of ~ 1.2 eV compared to 1.78 eV for films grown under identical conditions but without the substrate being coated. These values were determined from UV-Vis spectroscopy and Tauc plots. These optical band gaps correspond to polycrystalline silicon and amorphous silicon respectively, meaning that the films grown on NFD-coated substrates are polycrystalline silicon while those grown on uncoated substrates remain amorphous. Moreover, this novel technique has been used to fabricate a capacitor-like flash memory that has exhibited hysteresis width corresponding to charge storage density in the order of 1012 cm-2 with a retention time well above 20 days for a device with silicon films grown at 300 °C. Films grown on uncoated films have not exhibit any significant hysteresis, and thus no flash memory-like behaviour. Given that all process temperatures throughout the fabrication of the devices are less than 400 °C and that no annealing of any sort was done on the material and devices, this growth method is thermal budget efficient and meets the crucial process temperature requirements of 3-D flash memory. Furthermore, the technique is glass compatible, which could prove a major step towards the acquisition of flash memory-integrated systems on glass, as well as other applications requiring low temperature polycrystalline silicon.

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HOU, AN-SANG, and 侯安桑. "Computer temperature control by adaptive method." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/75745933194872293966.

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Fu, Ching-Yuan, and 傅慶源. "An accurate method for calculating color temperature." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/7z3fqz.

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碩士
中華大學
電機工程學系碩士在職專班
101
This thesis studies the accurate method to calculate the color temperature of a CIE1931 color coordinates. From (1) the relation of blackbody radiation color coordinates and color temperature and (2) the relation of the slope of isotemperature line and color temperature, we can accurate solve the color temperature for a given color coordinates.

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30

Tsai, Ming-Hong, and 蔡明宏. "A Temperature Compensation Method to Infrared Microbolometer." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/98384226075272842430.

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碩士
國立交通大學
光電工程所
88
The purpose of this research is to study the method of ambient compensation of infrared microbolometer. All thermal-conductivity-type sensors are strongly affected by the ambient temperature variation, which results in thermal drift at sensor output. Hence it is always necessary to provide a way of compensating the drift, when a microbolometer is used for radiation measurement. A special dummy compensation method is used. Using silicon micromachining technique, a sensor and a dummy are made on the silicon die with identical very linearly dependent Pt material. Therefore the temperature variation results in a common-mode noise in both devices and can be easily reduced. The sensor and dummy are drived by two constant current sources forming a bridge. The drift can be reduced by adjusting the dummy current to a specific value related to the sensor current. The results of the experiment shows that the drift can be reduced to an extent of 0.14V/°C. In the study an electronic thermal model created by Spice language is also built to simulate our circuit and to verify correctly of compensation theory.

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31

Lin, Li-An, and 林立桉. "A self-learning method to determine comfortable temperature for temperature control appliance." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/21685077388042520309.

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碩士
國立臺灣科技大學
電機工程系
103
In recent years , people gradually pay attention to the quality of home life,Smart Home have been frequently discussed in the last decade , the universality and using rate of the mobile devices have been increased , which leads many commercial investing in it. The intelligent control of home appliance is one of the most popular tepies in relative fields. Because people will feel the temperature all the time, so the air-conditioning control becomes very important. For users, in different seasons, different time to start air-conditioned, the desired temperature are different. But when users start air conditioning, they must enter the temperature manually, it is too cumbersome. And sometimes users does not know what the temperature is comfortable for them. In order to improve this problem, this thesis proposed a self-learning method to determine comfortable temperature for temperature control appliance by recording and analysing the value set by user. The method by learning and correcting again and again, temperature control appliance could recognize the user's habits more and more precisely as the time goes by. The simulation results in the end of this thesis has shown the effect of method is according with our expectation.

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32

Jung, Ying-Rong, and 鍾穎榮. "Temperature Compensated Method of 3D Printing Laminate Layer." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9utzw5.

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碩士
正修科技大學
電子工程研究所
105
Temperature Compensated Method of 3D Printng Laminate Layer Student：Ying-Rong Jung Advisor：Jyh-Haw Wang Department of Electronic Engineering Cheng Shiu University Kaohsiung City, Taiwan, Republic of China Abstract Layered manufacturing, also known as 3-dimensional printing (3D printing), is the use of stacking manufacturing methods layer by layer. Recently, the three-dimensional printing technology developed rapidly, together with the three-dimensional printing technology patent unlocked.has caused this technology greatly to simplify the process of producing complex parts and personalized productions people have pursued,especially the simplest, easiest processing technology of melting extrusion molding.However,When we use the melt extrusion molding processing technology for the three-dimensional printing, an adhesive layer often does not completely come into contact with the laminated cooling because of its waiting for the stack. Then, it will be easy to make a layer with the adhesive layer interface, won’t attach completely.So, the three-dimensional printing will be caused by the uncompleted product stacking. Therefore, the formation of print will fail, the success rate of three-dimensional printing will not be high, and those manufactured products will be flawed and damaged easy. This paper presents a new solution which is the stacking area temperature compensation method. Before printing, this method, consisting of the temperature sensor, heating bar, fan, controller, motherboard, will first input materials (PLA) melting point temperature (175℃) and set the detection temperature (upper limit +3℃ lower limit -5℃). Then, during printing, the chang of the temperature will be detected back and forth.When the detection temperature is too low, then it will start heating rods. On the other hand, when the temperature is too high, it will start the cooling fan to cool down to reach the appropriate temperature. By the comparison of thetemperature compensation and no temperature compensation, the stacking area temperature compensation will effectively improve the previous print quality resuling from uncomplete stacking and no temperature compensation. Besides, it also can increase the success rate of finished printing products. Keywords: Laminated manufacturing, three-dimensional printing, stacking area, temperature compensation, constant temperature

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33

Wu, Hsin Hsien, and 吳信賢. "Thermal Analysis of Induction Motors Using Finite Element Method Coupling with Temperature-time Method." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/35351311462730533935.

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碩士
逢甲大學
電機工程研究所
85
Reliable design of electrical machines requires a knowledge of likely temperature distribution within the machine. The ability to predict an accurate temperature distribution in turn needs a knowledge of the iron loss distribution, which is the requirement input data for finite element analysis.In this thesis, the finite element method is used for predicting the temperature distribution in the stator of an induction motor under steady-state conditions. Due to the complicated physical geometry of many of the components, the anisotropic nature of the iron laminations, and windings used in the motor, a two- dimensional thermal model can not represent the problem accurately, especially when one considers the core ends of the motor. Hence, a three-dimensional model is used for the analysis. IFurthermore, an accurate information of the local losses in electrical machines is very important for thermal analysis using the finite element method. In this thesis the local losses are initially estimated from electromagnetic field analysis, then, a temperature-time method is employed to evaluate the distribution of loss in various parts of the machine. More accurate temperature distributions within the machine are then computed from the resulting loss density distribution. This analysis gives

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34

Lei, Jann-Hwan, and 雷震寰. "The Study on Dual-Temperature Drying Method of Peanut." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/82724042692782770452.

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35

Lin, Keng-hung, and 林根宏. "Investigation on emulsion characteristics using phase-inversion temperature method." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/16756465072050117222.

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碩士
國立臺灣海洋大學
輪機工程系
100
The effects of type and concentration of surfactants on emulsification properties and diesel engine emission characteristics of an emulsion prepared by a phase-inversion temperature method were investigated in this study. Non-ionic surfactants were used for the emulsion formation of silicon oil with de-ionic water at the first experimental stage. The engine performance and emission characteristics of soybean biodiesel, and emulsions prepared by mechanical stirring and phase-inversion temperature methods, respectively under constant engine torque and varied engine speeds were studied at the second experimental stage. The experimental results show that the emulsion prepared by the method of phase-inversion temperature had higher O2 emission, NOx emission and exhaust gas temperature while lower CO emission than the emulsion by mechanical stirring. The soybean biodiesel was found to have the lowest fuel consumption rate, brake specific fuel consumption, and CO emission while the highest exhaust gas temperature, NOx emission, and O2 emission among those three fuels.

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36

LIU, CHENG-TSO, and 劉政佐. "Assessment Junction Temperature Measurement Method for Light Emitting Diode." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/37198580486039770142.

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碩士
中華大學
電機工程學系碩士班
103
Recently LED (Light Emitting Diode) under rapidly development changes the requirement and selectivity of light source. LED improves the green technologies and energy savings. LED possessing the characteristics of energy saving, long life, small size, high speed response applies in wide area. Now the LED becomes the main light source of lighting equipment and instruments. Colors of LED depend on different semiconductor materials and the high power LED can be a light source. The main problem of high power LED is the junction temperature that causes the heat accumulation. According to product design, reliability analysis, the junction temperature should be measured accurately. In this thesis, the potential drop method is proposed to estimate the junction temperature. The design of tasting platform consisting of inside devices and LED measures the junction temperatures under two different environment temperatures: 25 ℃ and 85 ℃.

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37

Haarhoff, Lukas Johannes. "A Monte Carlo method for thermal building simulation." Diss., 2001. http://hdl.handle.net/2263/27401.

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Please read the abstract in the section 00front of this document
Dissertation (MEng (Mechanical Engineering))--University of Pretoria, 2007.
Mechanical and Aeronautical Engineering
MEng
unrestricted

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38

HUANG, CHAO-JEN, and 黃昭仁. "Preparation of Copper Nanoparticles by ChemicalReduction Method at Room-Temperature." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/29986937119969173348.

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碩士
中原大學
化學工程研究所
96
A number of different ways have been developed to prepare metal nano-particles. Some of these methods include photoreduction and reduction using various reducing agents in association with protective polymers or surfactants. However, it has been argued that the stabilizer or protective polymer used for stabilization of metal nanoparticles covers its surface and hence can reduce the catalytic properties of the metal particles. In this paper, we report a novel solution phase reduction method for preparing copper nanoparticles, which does not require steric stabilizing agents. Copper metal nanoparticles was formed with a novel reducing agent, and were characterized using x-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, XPS and EDS analyses. The average diameter of copper nanoparticles was measured to be < 20 nm. The crystal structure of copper nanoparticles was determined to be a face centered cubic single crystal structure, which is the same as the bulk copper.

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39

Yang, ChuaHao, and 楊家豪. "Grown of carbon nanostructures by low-temperature aqueous solution method." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/96419061886904564060.

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碩士
明志科技大學
材料工程研究所
100
This study present a simple method to produce a lot of carbon as micro and nanostructure in aqueous solution at low temperature (85 °C). The structures have been observed two basic units by transmission electron microscopy (TEM): thin carbon nanoribbons, monolayer graphene. This method addition to obtain two basic units and found that synthesize multi-wall carbon nanotube (MWCNTs) without catalyst and carbon basin-shape structure. We further found that the carbon nanoribbons can self-assembly to form ribbon type of graphite nanofibers, carbon nanorings and MWCNTs without catalyst. The basin-shape structure where constitute came from the graphene and nanoribbons edge of fracture. The MWCNTs can become thicker by sticking nanoribbons on the wall, and growth to the micrometers for future.

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40

Wang, Chen-Yun, and 王貞雲. "Zinc Oxide Nanowires Synthesized by Low-temperature Aqueous Solution Method." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/8bm48k.

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碩士
國立臺北科技大學
材料科學與工程研究所
95
In this study, zinc oxide nanowires was successfully grown on ZnO/Si substrate using low-temperature aqueous solution method. We firstly study the influences of the ZnO buffer layer on the Si substrate on the crystal direction of zinc oxide nanowires. Then the effects of solution concentration, growth time, and the ratio of Zn(NO3)2 and C6H12N4 in the solution on the morphology and size of zinc oxide nanowires were also investigated. Our experimental results indicate that the zinc oxide nanowires have uniform C-axis preferred orientation when the zinc oxide buffer layer grows along [0001] direction. The surface roughness of zinc oxide buffer layer would affect the nucleus sites of zinc oxide nanowires, the higher the surface roughness is, the larger number of the nucleus sites is, which leads to high number density of nanowires grown. If the solution is stirred incessantly, the growth rate of the nanowires increases. The diameter of zinc oxide nanowires is determined by the concentration of solution. In our experiment, we can obtain the high quality columnar grain with hexagonal structure when the concentration of solution is 0.05 M. If the content of Zn(NO3)2 is more than C6H12N4, the length of zinc oxide nanowires is almost equal and is increased with an increase of reaction time. We also can obtain other geometries of zinc oxide such as ZnO thin film or ZnO nanotube, by suitably controlling the processing parameters of reaction time and concentration.

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41

Lin, Chen-Han, and 林辰翰. "LOW-TEMPERATURE FABRICATION METHOD OF CARBON NANOTUBES-BASED GAS SENSOR." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/yc74n7.

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碩士
國立臺北科技大學
機電整合研究所
96
Low temperature processes are the better way to integrate CNTs with CMOS chips into array-type gas sensors. The metal used in CMOS is almost Al-Si-Cu alloy, which make the sustainable temperature of CMOS structures be in the range of 400-500℃. For this goal, developing a fabrication method of CNT electronic devices at low temperature is needed. To fabricate CNTs-based gas sensors at low temperature, here, we offer a new fabrication method of CNTs-based gas sensors. The oxidized silicon substrate was modified with 3-aminopropyltriethoxysilane (APTS) to form aminoterminated (–NH2) self-assembled monolayer (SAM) on the surface. The chemical adhesion of CNTs to surface treated is due to the presence of positive charges or amine groups on the surface. After CNTs adhered to SiO2 surface, we deposited interdigitated electrode (IDE) on the SiO2 surface. We experimentally found that the resistances of CNT electronic devices at room temperature typically ranged from several hundreds Ω to several of kΩ, depending on the density of the MWCNTs across the IDE fingers. An array-type CNTs-based gas sensor was made up of many CNTs-based gas sensors. The initial resistance values of these sensors were not the same, we tuned the resistance value of gas sensor equally by trimming. A lateral cut in the IDE narrows the current flow path and increases the resistance value. The trim changes the initial resistance values of these gas sensors until they have acceptable tolerance. At room temperature, our CNTs-based gas sensors were able to detect CO and NH3 in 10 ppm.

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42

Wu, Jun-Sheng, and 吳俊昇. "ZnO nanorods and nanoneedles grown by low-temperature solution method." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/v83824.

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碩士
國立虎尾科技大學
光電與材料科技研究所
95
In this study, we have made efforts to develop a novel chemical-liquid deposition technique for the low-temperature growth of highly oriented and densely packed ZnO nanorods on substrates through homogeneous nucleation of the zinc oxide seed layer for growing well-aligned ZnO nanorod arrays on the substrate. The results exhibite that the size of nanorod strongly depends on [Zn2+] concentration. Furthermore, the as-grown vertical ZnO nanowires were characterized by XRD, FE-SEM, Micro-Ranman and Micro-PL. Where the morphology of ZnO seed layers, pH, growth temperature and concentration of zinc salt in aqueous solution were important parameters to determine the nanorod growth.

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43

Lu, Yi-Sheng, and 盧益陞. "Study of the Taguchi method with PID Temperature Control System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/33295537341545609316.

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碩士
桃園創新技術學院
機械工程系機械與機電工程碩士班
103
Traditionally, when factory design the air-conditioner system they usually get vehicle indoor information by quick and efficient energy-saving heating and cooling ventilation machine" system, adding double-tube heat exchanger device, and then this study re-use of heat supplied to the heat pump water heater, integrate and become a "window-type air-conditioning unit variable throttle the development of combined heat pump system", which the machine structure element extends from the small air conditioning unit, the condenser, evaporator individual retrofitting cross-flow fan placed in a parallel surface, and the installation of the double-pipe heat exchanger, refrigerant is performed using heat conduction, the performance of the excess energy by the double-pipe heat exchanger, the heat transferred to the water bucket which, through the ventilation machine function, so that the cold water heat pump water heater tank circulating within the sustainable increase water performance, research and development to achieve a variable throttle window-type air-conditioning unit combines heat pump system is designed, developed this innovative productions, an increase of more energy-saving and facilitate more features, but also to enhance this type of aircraft and the competitiveness of the market demand., then they can regulate air-conditioner system according the results. But actually the experimental method takes a lot of resources. With MATLAB numerical technology great developing, many analyzer use numerical method to improve the passenger’s thermal comfort and understand the thermal behavior within vehicle. However, the indoor vehicles analysis correlated closely with the air conditioner and the outdoor environmental condition. In this study, the finite element analysis, software, MATLAB, is used to PID analyze the Unknown Uncertainty of the control theory. Analysis transfer functions model，to find transfer functions With MATLAB numerical technology Kp、Ki、Kd get the optimal design parameter sand into actual control system and adjust PID parameter to achieve the Energy saving and Efficiency. The air temperature relation between inlet and outlet vents calculated b control theoretical equations for heat exchanger, transfer functions model and variable throttle heat transfer at the wall were regard as boundary conditions. Under those boundary conditions, we used numerical analysis software MATLAB to calculate the air temperature and velocity distributions within vehicle. According the analysis results and PID thermal comfort model, we can measure the passenger’s thermal comfort, and develop. This research optimize the control factors of Temperature Control system, utilizes Taguchi-method L9(33) Orthogonal Array table to do experimental design. It also utilizes The Nominal-the-Better quality characteristics produce the SN ratio, discovered that these factors change can affect the Temperature Control system’s performance. As to Taguchi Method, which truly provides both time-saving and the effective experiment principle, reduces simulation frequency as far as possible. Through the（Nominal-is-best） quantity analysis to discover the influence simulate result the principle factor. The research analyzes system according to the automobile body quantity and the Temperature and time Control system reaction time as the datum statistical table, discovers each parameter the best hypothesis. Through PID simulation analysis, the parameter was chosen to be able to reduce fluctuation truly, enhances vehicle’s comfortableness.

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44

CHEN, MING-LIANG, and 陳明亮. "An analysis of drill temperature distributions by finite element method." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/79747200661655516413.

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45

Chuang, Yung-Chun, and 莊永淳. "Synthesis of Tin Nanoparticles by Chemical Reduction Method in Room Temperature." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/51693174607278408675.

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碩士
中原大學
化學工程研究所
95
Owing to advances in nanotechnology, metallic nanoparticles have been applied to several fields, including optics, semiconductors and optoelectronics, etc. Applications of tin nanoparticles are in the preparation of metal films, as lithium alloy anodes for rechargeable batteries, as precursors to tin oxides nanoparticles for use as gas sensors, and as solder materials for ball grid array. In this study, we report a novel room-temperature solution phase reduction of SnCl2 with a novel reduction agent, which can afford colloidal tin nanoparticles with a diameter less than 20 nm. The particles are analyzed by using x-ray powder diffraction, transimission electron microscopy, scanning electron microscopy, electron spectroscopy for chemical analysis, energy dispersion spectroscopy, and differential scanning calorimetry.

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46

Li, Chia-Ming, and 李佳旻. "Preparing Electrochromic Nickel Oxide Thin Film by Low Temperature Oxidizing Method." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/17965900713745874342.

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碩士
逢甲大學
化學工程學所
91
Electrochromism is currently attracting much interest in academia and industries. Electrochromic materials are classified two types that including of inorganic and organic ones. Inorganic of electrochromic materials have advantage that can suffer serious environments change. They are used for a variety of commercial applications. These include electrochromic display devices, smart windows in order to balance lighting, sun roof in car and safety glasses…etc. The nickel oxide smart window is one of them and has excellent performance. In this investigation we use electroless method and low temperature oxidation to prepare the nickel oxide thin film. The substrate is indium tin-dioxide (ITO) glass. Low temperature oxidation can treat curve surfaces. The most advantages of low temperature oxidation is less energy consumptive and good performance comparing with the conventional heat treatments. Preliminary results on the X-ray diffraction (XRD) and the scanning electron microscope (SEM) are reported. The deposited nickel change to nickel oxide with properly low temperature oxidizing time. The electrochromic properties are also analyzed by ultra violate (UV) and cyclic voltammetry (CV).

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47

Chiang, Yu-Hsin, and 蔣育欣. "ZnO nanorods thin film transistors by the low-temperature solution method." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/30524680601974200737.

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碩士
國立中正大學
光機電整合工程所
98
In this thesis, ZnO nanorods were fabricated by two-step process. In the first instance, the substrate was pre-coated seed layer by sol-gel spin-coating method before growing nanorods . Secondly, ZnO nanorods thin film were synthesized by Chemical bath deposition (CBD). ZnO nanorods thin films were measured by SEM, XRD and photo- luminescence spectra to get there physical characteristic. We fabricated the field effective transistor by using these ZnO nanorods thin films and measured I-V curve of these transistors. We obtained the ZnO nanorods thin film with field effect by 0.075 M of solution concentration, 75 ℃ of growth temperature and 90 minutes of growth time. The characteristic of devices were that Ion/Ioff ratio was 1.78 and channel mobility was 1.247 cm2/Vs has been determined. As we demonstrate here, the technique is easily controlled, low temperature, and low cost, and can be used to produce ZnO nanorods thin films with field effect.

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48

Liu, Pei-chieh, and 劉沛潔. "Feasibility Study on Domestic Sludge Drying by Low- Temperature Heating Method." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/07881749078655381099.

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碩士
國立中央大學
環境工程研究所在職專班
101
In Taiwan, the dewatered sludge of sewage treatment plant is mostly contracted out for transportation. Not only its cost is expensive, but also its exact destination is hard to efficiently control. Although sewage sludge is processed by thickening and dewatering in the treatment plant, the water content of the dewatered sludge is still high, ranging from 75% to 85%. Therefore, it will directly cause the increase of the transportation cost of the sludge, and is liable to pollute the environment. This study is based on a real case to dry the dewatered sludge of a secondary treatment plant in the northern Taiwan. To prevent from the high-temperature deterioration of the reusable material, the highest drying temperature was set at 105℃ and the water content of the dry sludge was reduced to about 30%. The relevant operational parameters were recorded on energy consumption and cost, followed by the benefit assessment of sludge-drying deduction. In addition, the examinations of constituents and heavy metals of the dried sludge were outsourced to the qualified laboratories. According to the examination results, the adaptable reuse method was recommended. Furthermore, to evaluate the adaptability of the localization model of the combined treatment of the sludge in Taiwan, the approach of Yokohama City in Japan was referred. Based on the prevailing regulations and limitations on the sludge reuse in Taiwan, it is found that the heavy metal contents, such as Cd, Hg, Cr, Ni, and Zn, are higher than those of the hazardous constituents limited in the ancillary compost fertilizer or the ancillary organic plantation media of the Fertilizer Management Law. In the case study of drying deduction of 53%, the sludge drying cost per metric ton ranges from NTD2,005 to NTD3,600. Compared with the directly outsourcing hauling and transportation cost of NTD4,500 per metric ton, it has potential economic benefit from drying deduction, in addition to reducing the sludge weight on a large scale, facilitating to clearance in plant, and promoting subsequent multipurpose reuse. Recovery energy from sludge is the application of biomass energy. Because there is no sludge-exclusive incinerator in Taiwan, the incineration of the dry sludge is usually mixed with the municipal waste. This study was based on the practical cases in Taipei City and New Taipei City to use the existing municipal waste incinerators in the regions to burn the sewage sludge in the regions concerned. Through the reuse of the recovery energy from sludge in the sewage treatment plant, and the power generation of the co-generation and the reuse of the materialized ash of the incinerators, the re-usage rate of the sludge will be increased and the complete zero waste will be reached. It is expected to associate with the sludge deduction, treatment, and reuse technologies in Taiwan to initiate the market of the multipurpose reuse, to well use the existing treatment facilities to fill up the rated garbage delivery amount guaranteed by the government, to increase the incineration rate of the garbage incinerator, to reduce the loading of the landfill, to achieve a triple benefit of pollution reduction, energy saving and carbon reduction, and resource recycle, and to comply with the international trend toward the energy recycle for exact solving the problem with the final treatment and disposal of sludge.

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Esieh, Ping-En, and 謝秉恩. "Routing Method for Ad Hoc Networks – Considering Temperature and Remaining Power." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/63899406355323827740.

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Abstract:

碩士
國立宜蘭大學
電子工程學系碩士班
96
Ad-hoc wireless network consist of all wireless mobile nodes, without any access point or fixed infrastructure. Because the life time of a node is limited by the battery power, many routing algorithms, such as MBCR、PSR and MPLR, take the condition of power consumption into considering, so as to extend the life time of the nodes or the networks. However, by observing the discharge curve of a battery, the total capacity of a battery depends on the surround temperature. Besides, the remaining power of a battery is not decides only by its voltage, but also by the surround temperature. As a result, by considering the battery temperature, the usage of a battery can be calculated more accurately and so does the route decision. In this thesis, we propose a method in order to correctly determine the battery usage ratio of each node in any temperature. By curve fitting method, a discharge curve is transformed into a polynomial equation which represents the usage ratio. In order to reduce the computation complexity, the equations are further simplified to lower order. We apply the method into MBCR、PSR and MPLR algorithm and compare the performance “with considering temperature” and “without considering temperature”. The simulation result reveals that our method can find a path which has better performance in any temperature.

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Chen, Jr-Yi, and 陳智一. "Simultaneous strain/temperature measurement with fiber Bragg grating using power method." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/762akg.

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Dissertations / Theses on the topic 'Temperature method'

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