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Добірка наукової літератури з теми "Resistance measurement method"

Автор: Grafiati
Опубліковано: 30 травня 2022
Оновлено: 31 травня 2022

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Статті в журналах з теми "Resistance measurement method"

1

Rinkunas, R., and S. Kuskevicius. "Contactless method of resistance measurement." Technical Physics 54, no. 1 (January 2009): 133–37. http://dx.doi.org/10.1134/s1063784209010204.

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2

Lipol, Lefayet Sultan, Mayedul Islam, and Nazrima Sultana. "The Resistance Measurement Method of the Conducting Textiles." European Scientific Journal, ESJ 12, no. 27 (September 30, 2016): 242. http://dx.doi.org/10.19044/esj.2016.v12n27p242.

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The report describes the technique to measure the resistance of some novel conducting threads. All of the measurements were performed in the EMC lab at SP Technical Research Institute of Sweden, Boras. The conducting threads were received from Ms. Azadeh Soroudi of the University of Boras. The conducting additive used for the threads was Carbon Black. The resistance was measured using two different methods: The two-terminal measurement method and the four-terminal measurement method. A result from the comparison of the two methods was that the two terminal measurement method provided more information than the fourterminal method. There seemed to be no advantage to use the four terminal method at all, for the resistance range studied.
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3

Nguyen, V. V., A. A. Shilin, and P. M. Momot. "PLC-based lumber humidity measurement method." Proceedings of the Southwest State University 25, no. 1 (May 30, 2021): 110–21. http://dx.doi.org/10.21869/2223-1560-2021-25-1-110-121.

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Purpose or research. The paper considers the solution of the scientific and practical problem of measuring the humidity content of lumber on the basis of a programmable logic controller (PLC), which makes it possible to implement control systems for drying lumber on inexpensive controllers of wide application with the advantages of modern SCADA systems.Methods. To achieve this goal, modern methods for assessing the humidity content of lumber by electrical resistance have been investigated. We have provided a review and analysis of the known dependences of the electrical resistance of lumber on moisture. It is noted the need to measure resistance in the range of 2.5 KΩ to 25 MΩ. The schematic solution for matching a high-resistance measurement bridge with an additional voltage source with a PLC is described here. We have proposed a method for calculating the matching scheme. Expressions are obtained for calculating humidity according to the data of an analog-to-digital converter. The procedure for setting up the measurement channel according to the readings of two reference measurements is presented.Results. The estimation of the measurement error of humidity and resistance is carried out. It is shown that a resistance measurement error of up to 20% leads to a humidity measurement error of up to 1%, provided that the parameters are correctly configured. To set it up, it is enough to take two reference measurements to complete the procedure for setting the humidity measurement parameters.Conclusion. In the process of designing modern systems for drying lumber, you can use the algorithms and programs of the technological process available and well presented in the literature for implementation on the PLC. The article offers a solution to the main problem of measuring the humidity content of lumber, which is necessary for these algorithms and programs. The material can be useful for researching technological stages of the drying process and developing industrial control systems based on inexpensive controllers.
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4

Mayer, V., D. Vejchar, and L. Pastorková. "Measurement of potato tubers resistance against mechanical loading." Research in Agricultural Engineering 54, No. 1 (March 3, 2008): 22–31. http://dx.doi.org/10.17221/708-rae.

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The contribution presents a method for the determination of the potato tubers resistance against mechanical loading, the measurement results obtained with the selected potato varieties, and the comparison of the latter. For testing the potato varieties samples, the method developed in Agrartechnik (ATB) Bornim (Germany) was verified and utilised. The potato samples were exposed to vertical vibrations with adjustable amplitude in the device constructed at the Research Institute of Agricultural Engineering, (RIAE) Prague, for testing tuber samples for mechanical loading. The potato samples cutting pictures were scanned by a web camera or a scanner, and the colour changes on the cuttings were evaluated by means of a computer program. In the paper are presented the results of two different measurements. Significant differences were found between four varieties regarding their resistance against equal mechanical load, and in one variety in different degrees of mechanical load for both early and late potatoes.
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Casans Berga, Silvia, Rafael Garcia-Gil, A. Edith Navarro Anton, and Alfredo Rosado-Muñoz. "Novel Wood Resistance Measurement Method Reducing the Initial Transient Instabilities Arising in DC Methods Due to Polarization Effects." Electronics 8, no. 11 (November 1, 2019): 1253. http://dx.doi.org/10.3390/electronics8111253.

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A novel method for measuring the electrical resistance in wood is presented. It is based on applying an Alternating Current (AC) to two electrodes rammed into the wood. The method reduces the transient time for value stabilization. In case of Direct Current (DC) resistance measurement methods, typically used in wood measurement, an initial transient exists, invalidating the measured value during an initial transient period. This measurement method uses an electronic circuit based on a relaxation oscillator where the wood automatically sets the oscillation frequency depending on its electrical resistance. Compared to other AC methods, this circuit greatly simplifies the measurement process, not requiring any previous analysis for wood AC frequency estimation. Experimental results for four different wood species showed that, in all cases, the transient response of the measured wood resistance is improved when compared to the DC resistance method, reducing the stabilization time from 10–12 min in DC measurements to almost zero for the novel measurement method. The deviation between the initial wood resistance measurement and the stable value resulted in a range between 0.2% and 5% with the proposed method, while a range between 6% and 10% was obtained when using the DC method. Moreover, the proposed circuit is able to detect changes in wood resistance produced by small variations in temperature and environmental relative humidity during continuous long term measurements. For repeatability analysis, it was verified that similar ambient conditions of temperature and relative humidity (variations lower than 1 °C and 1%, respectively) in different moments provided variations lower than 1.5%. The method can also be applied to other fiber materials affectd by polarization effects when an electrical current is applied into them.
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6

Officer, Todd M., Riccardo Pellegrino, Vito Brusasco, and Joseph R. Rodarte. "Measurement of pulmonary resistance and dynamic compliance with airway obstruction." Journal of Applied Physiology 85, no. 5 (November 1, 1998): 1982–88. http://dx.doi.org/10.1152/jappl.1998.85.5.1982.

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We compared four algorithms by using least squares regression for determination of pulmonary resistance and dynamic elastance in subjects with emphysema, normal subjects, and subjects with asthma before and after bronchoconstriction. The four methods evaluated include 1) a single resistance and elastance, 2) separate resistances and elastances for each half breath, 3) separate inspiratory and expiratory resistances with a single elastance, and 4) separate inspiratory and expiratory resistances, an expiratory volume interaction term, and a single elastance. All methods gave comparable results in normal and asthmatic subjects. We found expiratory resistance was larger than inspiratory resistance in normal and asthmatic subjects during control conditions, but inspiratory resistance was higher than expiratory resistance in subjects who experienced severe bronchoconstriction in response to methacholine. In subjects who are flow limited, method 2 gives a higher inspiratory resistance than would be computed by assuming that the elastic pressure-volume curve passes through the zero-flow points. Methods 1 and 3 overestimate dynamic elastance and inspiratory resistance. Method 4appears to identify flow limitation and dynamic hyperinflation and gives a good measure of inspiratory resistance and dynamic elastance.
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7

Zhang, Zhanlong, Hao Wu, Qingzhou Cao, Chen Luo, and Dongping Xiao. "Novel Method for Tower Grounding Resistance Measurement." Electric Power Components and Systems 45, no. 13 (August 9, 2017): 1404–12. http://dx.doi.org/10.1080/15325008.2017.1365102.

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8

Gupta, Rahul P., Robin McCarty, Jim Bierschenk, and Jeff Sharp. "Practical electrical contact resistance measurement method for bulk thermoelectric devices." MRS Proceedings 1490 (2013): 153–59. http://dx.doi.org/10.1557/opl.2012.1730.

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ABSTRACTAs thermoelectric (TE) element length decreases, the impact of contact resistance on TE device performance grows more significant. In fact, for a TE device containing 100-μm tall Bi2Te3TE elements, the figure of merit ratio (ZTDevice/ZTMaterial) drops from 0.9 to 0.5 as the contact resistivity increases from 5 x 10-07 to 5 x 10-06 Ω-cm2. To understand the effects of contact resistance on bulk TE device performance, a reliable experimental measurement method is needed. There are many popular methods to extract contact resistance such as Transmission Line Measurements (TLM) and Kelvin Cross Bridge Resistor method (KCBR), but they are only well-suited for measuring metal contacts on thin films and do not necessarily translate to measuring contact resistance on bulk thermoelectric materials. The authors present a new measurement technique that precisely measures contact resistance (on the order of 5 x 10-07 Ω-cm2) on bulk thermoelectric materials by processing stacks of bulk, metal-coated TE wafers using TE industry standard processes. One advantage of this technique is that it exploits realistic TE device manufacturing techniques and results in an almost device-like structure, therefore representing a realistic value for electrical contact resistance in a bulk TE device. Contact resistance measurements for metal contacts to n- and p-type Bi2Te3 alloys are presented and an estimate of the accuracy of the measurements is discussed.
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9

Shen, Hua Jing. "Measurement of Impulse Grounding Resistance." Advanced Materials Research 546-547 (July 2012): 289–94. http://dx.doi.org/10.4028/www.scientific.net/amr.546-547.289.

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A kind of measurement method of impulse grounding resistance is proposed. The measurement method of impulse grounding resistance is also analyzed and discussed theoretically. The hardware and software scheme of measurement system is given. The method of simulation of thunder current and transformation calculation is better than the method of work-frequency measurement by the analysis and comparison. By using the method, the thundering course can not only be simulated , but also the impulse grounding resistance can be calculated directly in the scene. In the end, a simulation result is given. Simulation result show that the method proposed in the paper is effective and feasible.
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10

Clarke, Robin E., Bahman Shabani, and Gary Rosengarten. "A difference technique to avoid interface errors in measurement of high-conductance thermal insulation." Journal of Building Physics 40, no. 6 (May 23, 2016): 561–78. http://dx.doi.org/10.1177/1744259116637863.

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Lower limits of measurement are prescribed within all steady-state test methods for thermal insulation. The limit, typically 0.1 m2 K/W, is largely required because of the increasing significance of interface resistance. We have previously proposed the use of a difference method, in conjunction with flexible buffer materials, to minimize the effects of interface resistance and facilitate measurement of rigid materials below these limits. We have now studied this approach at higher thermal resistances and incorporated a refinement to include a known reference specimen in the difference measurement, which largely eliminates the residual resistance terms. Specimens of expanded polystyrene and cast acrylic were measured in a conventional heat flow meter apparatus using two alternative silicone buffer materials: one solid and the other a sponge. Analysis also included earlier measurements of 12 more highly conducting specimens. Across all of these, thermal resistance values obtained by the difference method were lower between 0.008 and 0.016 m2 K/W, attributable to removing the contribution of interface resistance.
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Дисертації з теми "Resistance measurement method"

1

Liang, Changnian. "A new surface resistance measurement method with ultrahigh sensitivity." Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/40299.

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A superconducting niobium triaxial cavity has been designed and fabricated to study residual surface resistance of planar superconducting materials. Unlike many other structures where the test samples are placed in strong magnetic field positions, the edge of a 25.4 mm or larger diameter sample in the triaxial cavity is located outside the strong field region. Therefore, the edge effects and possible losses between the thin film and the substrate have been minimized in this design, ensuring that the induced RF losses are intrinsic to the test material. The fundamental resonant frequency of the cavity is 1.5 GHz, the same as the working frequency of CEBAF cavities. The cavity has a compact size compared to its TE₀₁₁ counterpart, which makes it more sensitive to the sample's loss.
Ph. D.
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2

Jones, Cameron Bennion. "Development and Validation of a Vibration-Based Sound Power Measurement Method." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/9260.

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The International Organization for Standardization (ISO) provides no vibration-based sound power measurement standard that provides Precision (Grade 1) results. Current standards that provide Precision (Grade 1) results require known acoustic environments or complex setups. This thesis details the Vibration Based Radiation Mode (VBRM) method as one approach that could potentially be used to develop a Precision (Grade 1) standard. The VBRM method uses measured surface velocities of a structure and combines them with the radiation resistance matrix to calculate sound power. In this thesis the VBRM method is used to measure the sound power of a single-plate and multiple plate system. The results are compared to sound power measurements using ISO 3741 and good alignment between the 200 Hz and 4 kHz one-third octave band is shown. It also shows that in the case of two plates separated by a distance and driven with uncorrelated sources, the contribution to sound power of each individual plate can be calculated while they are simultaneously excited. The VBRM method is then extended to account for acoustically radiating cylindrical geometries. The mathematical formulations of the radiation resistance matrix and the accompanying acoustic radiation modes of a baffled cylinder are developed. Numberical sound power calculations using the VBRM method and a boundary element method (BEM) are compared and show good alignment. Experimental surface velocity measurements of a cylinder are taken using a scanning laser Doppler vibrometer (SLDV) and the VBRM method is used to calculate the sound power of a cylinder experimentally. The results are compared to sound power measurements taken using ISO 3741.
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3

Bourouga, Brahim. "Etude d'une methode de mesure instationnaire de resistance thermique de contact entre parois cylindriques concentriques minces." Nantes, 1986. http://www.theses.fr/1986NANT2063.

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Developpement d'dune methode de mesure de resistance thermique de contact dans des doubles tubes metalliques minces destines a la fabrication de condenseurs pour des installations nucleaire. La methode, qui fonctionne en regime instationnaire, est basee sur l'analyse de la reponse de l'echantillon a une sollicitation thermique du type echelon temperature
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4

Burešová, Eliška. "Analýza metod měření vlhkosti ve stavebních materiálech." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2021. http://www.nusl.cz/ntk/nusl-433576.

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The diploma thesis is focused on the issue of measuring the moisture content in building materials using indirect methods that allow its long-term measurement. The theoretical part of the thesis provides an overview of the forms of moisture in porous building materials and provide an overview of the principles of measuring moisture content. In the experimental part of the thesis, the aim is to verify the available methods for long-term monitoring of moisture in building materials built into building structures. Proven methods of measuring humidity include resistance, capacitive and microwave methods and their comparison with the results of gravimetric measurements. At the end of the work is an evaluation of knowledge and recommendations for further research in this area.
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Dirbák, Štefan. "Návrh a realizace plošného měření rezistivity půdy." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-413053.

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This diploma thesis deals with research and study of soil impedance measurement and soil resistivity. Currently, the issue of measuring and determining soil resistance is ensured through the gradual measurement of certain soil parameters at individual points of the surface (or depth of the ground). This thesis focuses on the idea of measuring soil resistance on a certain area using a network of electrodes through a suitably designed test, measurement and evaluation system. Such an approach may find application in the need to determine soil parameters (such as resistivity) on a specific demarcated area (or depth). The prospect of such an application can be seen in saving time, energy and money needed to measure the soil resistivity of a certain area (as opposed to gradual point measurements). The configuration possibilities of OMICRON CPC 100 measuring instrument were used for the design and implementation of the measuring system for the mentioned purpose. The work is completed by verification of the proposed solution by real measurement with evaluation of the results.
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Coelho, Rooney Ribeiro Albuquerque. "Application of the finite element method as assistance to the project and commissioning of electrical grounding systems." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14461.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
The main aim of this work is to apply the finite element method (FEM), modeled in short circuit current conduction problems at industrial frequency, calculating grounding resistance and verifying whether a particular project is within the safety specifications. The work optimization techniques for soil modeling are used and the FEM is applied as a way to aid substation commissioning, simulating the Fall of Potential method (FOP) as well as step and touch potential experimenting. The research presents the optimal model of soil found by the minimization of the error between the apparent resistivity curve extracted from electrical soil resistivity measurements. The method of Wenner and a theoretical curve of apparent resistivity for a model of "N" horizontal layers is used as well as the algorithm Particle Swarm Optimization (PSO); a fairly consolidated optimization, a metaheuristic, which recorded an excellent performance when applied to a solution of this problem. Various soil stratification were performed using optimization techniques, and the results of case studies that use graph method, extracted from literature were confronted with this method. The model of grounding problems using the FEM was presented as an alternative solution to the project using the IEEE Std 80, being possible to determine the spatial distribution of the electric potential at all points of the soil, which was modeled as heterogeneous, so getting to know the regions of the project which have the highest potential levels of step and touch. The FEM was also applied to determine the exact location of potential probe in the ground resistance measurement test which was validated through field experiments and through results extracted from literature. The method was also applied to the determination of the potential levels of step and touch existing in a substation, being the testing simulated and proven through field experiments.
Este trabalho tem como objetivo principal, aplicar o mÃtodo dos elementos finitos (FEM), modelados em problemas de conduÃÃo de corrente de curto-circuito à frequÃncia industrial, calculando a resistÃncia de aterramento e verificando se um determinado projeto està dentro das especificaÃÃes de seguranÃa. SÃo utilizadas tÃcnicas de otimizaÃÃo para a modelagem do solo e aplicado o FEM como forma de auxÃlio ao comissionamento de subestaÃÃes, simulando o mÃtodo da queda de potencial e ensaios de potenciais de passo e de toque. à apresentado o modelo Ãtimo do solo, encontrado atravÃs da minimizaÃÃo do erro entre a curva de resistividade aparente extraÃda de mediÃÃes de resistividade elÃtrica do solo atravÃs do mÃtodo de Wenner e uma curva de resistividade aparente teÃrica para um modelo de âNâ camadas horizontais. O referido modelo utiliza o algoritmo Particle Swarm Optimization (PSO), uma metaheurÃstica de otimizaÃÃo bastante consolidada e que apresenta uma excelente performance quando aplicada à resoluÃÃo deste problema. Foram realizadas diversas estratificaÃÃes do solo utilizando tÃcnicas de otimizaÃÃo. Quanto ao resultado de estudos de caso foram utilizados mÃtodos grÃficos extraÃdos da literatura e confrontados com este mÃtodo. O modelo de problemas de aterramento utilizando o FEM foi apresentado como soluÃÃo alternativa ao projeto utilizando a norma IEEE Std 80, sendo possÃvel determinar a distribuiÃÃo espacial do potencial elÃtrico em todos os pontos do solo, que foi modelado como heterogÃneo, conhecendo-se assim as regiÃes do projeto que possuem os maiores nÃveis de potenciais de passo e de toque. O FEM tambÃm foi aplicado na determinaÃÃo da localizaÃÃo exata da sonda de potencial no ensaio de mediÃÃo de resistÃncia de aterramento, sendo validado atravÃs de ensaios de campo e atravÃs de resultados extraÃdos da literatura. O referido mÃtodo tambÃm foi aplicado na determinaÃÃo dos nÃveis de potencias de passo e de toque existentes em uma subestaÃÃo, sendo os ensaios simulados e comprovados atravÃs de experimentos de campo.
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7

Khoury, Antonio. "Parametres caracteristiques d'une photopile : etude experimentale, influence de la temperature." Perpignan, 1987. http://www.theses.fr/1987PERP0026.

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Etude de la determination des parametres caracterisant une photopile afin de proposer des methodes pratiques de mesure et d'en fixer les limites d'utilisation. Toutes les methodes connues pour mesurer la resistance serie d'une cellule ont ete utilisees et on montre que les ecarts importants observes proviennent de l'absence d'un controle precis de la temperature. On montre la necessite de determiner, ensemble le facteur de qualite et le courant inverse des cellules. Determination de la variation des parametres avec la temperature les mecanismes de transport des changes sont alors consideres
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8

Gottwald, Michal. "Dynamický model stejnosměrného motoru s využitím metody konečných prvků." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219003.

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My diploma thesis deals with a specific dynamic model of DC motor with the parameters obtained from the calculation and from the program using the finite element method. It shows how much accurate results can be achieved in the model, if you use only the values which can be measured, recorded and calculated on the engine. This thesis contens three parts. First part describes the structure and function of DC motor and the basic principle and the use of FEM. Next is calculation analytical and numerical parameters. The search parameters include torque, resistance and inductance of armature winding, resistance and inductance of excitation windings. The last part is dedicated to creating a dynamic model. Results from the dynamic model and measured values are compared in the conclusion of my thesis.
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9

Wisung, Grete. "Method evaluation : Electrical surface resistance measurements on coated conductive textiles." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-14769.

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This thesis has evaluated how electrical surface resistance can be measured on conductive coated textiles using two different probes. The electrical surface resistance is a measurement for how difficult it is for current to flow through a material. For textiles, the surface resistance can be measured using four metallic plates, that measure the difference between current supply and voltage drop, this method is called a linear four-point probe.   There is no standard method for measuring the electrical surface resistance on conductive textiles. Therefore, it is not possible to compare textiles made by different producers. It is also not possible to decide what the true resistance is and as conductive textiles are becoming more popular to use, this has started to become a problem in the industry.   Two probes with electrodes of different dimensions were used to evaluate how different electrodes would affect the measured resistance. Measurements were conducted on conductive coated textiles with varying parameters, like coating thickness, sample size and textile construction, to show how the electrical resistance properties differ depending on what probe was used.   It was found that in contrast to other research on conductive textiles and collinear four-point probes, the probes used in this study could detect electrical anisotropic properties. The resistance was different depending on what angle it was measured in. This was found for both a thicker coating and a thinner one. It was also found that the probes could detect a correlation between the angular resistance and the textile construction used.   By measuring the resistance on small samples with the same dimension as the probes electrodes, the resistance was increased compared to when measurements were conducted on samples with dimensions significantly larger than the probes.   Furthermore, the results showed that increasing the distance between the inner electrodes of the probe decreased the measured resistance for both large and small samples. Additionally, it was found that by increasing the width of the outer electrodes the resistance was decreased, an increase in outer electrode width also made it easier to detect electrical anisotropic properties.
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Vítek, Jiří. "Optimalizace tenkých oxidových vrstev kovových materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220969.

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This thesis is focused on the description of the method of reactive sputtering of thin films. Currently, there are many ways how to create thin films and there are many applications of thin films in various industrial sectors. In this paper at the first are listed the issue of thin films, followed by an overview of the deposition techniques and of the chemical analysis of deposited thin films. It also describes the four-point measurement method of sheet resistance, mechanical test of adhesion and optical properties. At the end of the theoretical part are described the material composition of the deposited films. The goal of the practical part is to optimize the deposition process of the mixed layer of indium tin oxide (In2O3: SnO2) and contribute to the overall understanding of the influence of annealing on the layer. There were created six series of samples with that applied layers. First, the work focused on examining of the influence of annealing on the throughput in the whole measuring range, and then comparing the series due to the transmittance in the visible light spectrum. Furthermore were compared the value of sheet resistance of unannealed and subsequently annealed samples.
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Книги з теми "Resistance measurement method"

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Institute, American National Standards. ESD Association standard test method for electrostatic discharge sensitivity testing: Human body model (HBM) component level. Rome, NY: Electrostatic Discharge Association, 2007.

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2

Evtushenko, Sergej, and Viktor Logvinov. Resistance of materials. Laboratory works. 4th edition. 4th ed. ru: Publishing Center RIOR, 2016. http://dx.doi.org/10.12737/16966.

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Data on laboratory works on resistance of materials are provided, the assessment of errors of results of measurements and experiments is given, statistical processing of experimental data is in detail stated. The book contains information on nondestructive methods and control devices of characteristics and diagnostics of materials and designs. In a grant the International system of units (SI) (tab. 1 of the Appendix) is used, designations of sizes are accepted according to the international recommendations of ISO. Data on physicomechanical characteristics of steel, cast iron, non-ferrous metals, wood and polymers and the allowed tension for them are provided in tab. 2-8 of the Appendix. The grant is intended for the students studying courses of resistance of materials, mechanics of materials and designs, applied mechanics, construction mechanics and construction designs.
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3

Kajaste-Rudnitski, Juri. Numerical model of thermoelastic-plastic concrete material. Espoo: Technical Research Centre of Finland, 1993.

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4

Matasovic, Neven. Practices and procedures for site-specific evaluations of earthquake ground motions. Washington, D.C: Transportation Research Board, 2012.

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5

V, Collura Joseph, and Dryden Flight Research Facility, eds. A limited in-flight evaluation of the constant current loop strain measurement method. Edwards, Calif: National Aeronautics and Space Administration, Dryden Flight Research Center, 1997.

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V, Collura Joseph, and Dryden Flight Research Facility, eds. A limited in-flight evaluation of the constant current loop strain measurement method. Edwards, Calif: National Aeronautics and Space Administration, Dryden Flight Research Center, 1997.

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V, Collura Joseph, and Dryden Flight Research Facility, eds. A limited in-flight evaluation of the constant current loop strain measurement method. Edwards, Calif: National Aeronautics and Space Administration, Dryden Flight Research Center, 1997.

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8

Herrmann, Konrad, ed. Hardness Testing. ASM International, 2011. http://dx.doi.org/10.31399/asm.tb.htpa.9781627083461.

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Hardness Testing: Principles and Applications is an in-depth study of one of the most fundamental properties of materials and the tools and techniques that have been developed to measure it. Hardness, as defined in the first chapter, is a type of resistance to deformation, the roots of which lie in the packing density of atoms and the bonding forces that keep them in place. As subsequent chapters explain, the hardness of metals, plastics, rubber, and ceramics can be measured as a response to an applied stress (whether static or dynamic), via noncontact sensing, or through an instrumented indenter. Most of the hardness tests used in industry, including Rockwell, Vickers, Brinell, and Knoop methods, are based on static measurements that have become standardized over the years. The practices and procedures associated with these methods are described in detail along with relevant theory and practical considerations such as calibration requirements and uncertainty concerns. Other chapters provide similar information on dynamic tests, including Shore and Leeb methods, nondestructive tests, including electromagnetic, photothermal, and ultrasonic sensing, and indentation measurement techniques. The chapters also include application examples as well as guidelines and recommendations for selecting and implementing hardness tests. For information on the print version, ISBN 978-1-61503-832-9, follow this link.
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9

K, Banerjee P., and United States. National Aeronautics and Space Administration., eds. 3-D inelastic analysis methods for hot section components.: Third annual status report. [Washington, DC]: National Aeronautics and Space Administration, 1987.

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K, Banerjee P., and United States. National Aeronautics and Space Administration., eds. 3-D inelastic analysis methods for hot section components.: Third annual status report. [Washington, DC]: National Aeronautics and Space Administration, 1987.

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Частини книг з теми "Resistance measurement method"

1

Huang, Songran, and Liwei Song. "Wireless Passive Measurement Method for Resistance Strain Sensor." In Lecture Notes in Electrical Engineering, 736–48. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-32-9441-7_76.

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Chollier-Brym, M. J., D. Laroche, A. Alexandre, M. Landry, C. Simard, L. Simard, and D. Ringuette. "New Method for Representative Measurement of Anode Electrical Resistance." In Light Metals 2012, 1299–302. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-319-48179-1_224.

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J. Chollier-Brym, M., D. Laroche, A. Alexandre, M. Landry, C. Simard, L. Simard, and D. Ringuette. "New Method for Representative Measurement of Anode Electrical Resistance." In Light Metals 2012, 1299–302. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118359259.ch224.

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Murase, Satoru, Rikuo Ogawa, Takashi Saitoh, Hidezumi Moriai, Teruo Matsushita, and Kozo Osamura. "Residual Resistance Ratio Measurement Method of Cu/Nb3Sn Composite Conductors." In Advances in Superconductivity XII, 700–702. Tokyo: Springer Japan, 2000. http://dx.doi.org/10.1007/978-4-431-66877-0_209.

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Goszczyński, Tadeusz. "New Method for Calculation the Error of Temperature Difference Measurement with Platinum Resistance Thermometers (PRT)." In Recent Advances in Systems, Control and Information Technology, 427–34. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-48923-0_45.

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Okai, Daisuke, Masanobu Kusunoki, Masashi Mukaida, and Shigetoshi Ohshima. "Effect of Cavity’s Loss on the Measurement Accuracy of the Surface Resistance by Microstripline Resonator Method." In Advances in Superconductivity XII, 1063–65. Tokyo: Springer Japan, 2000. http://dx.doi.org/10.1007/978-4-431-66877-0_316.

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Olszowiec, Piotr. "Insulation Resistance Measurement Methods." In Lecture Notes in Electrical Engineering, 83–91. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-07010-0_6.

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Olszowiec, Piotr. "Insulation Resistance Measurement Methods." In Lecture Notes in Electrical Engineering, 79–87. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-29755-7_6.

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Kato, Masahiko, Jinhua Zheng, Seiji Takezoe, and Keijiro Nakasa. "Evaluation of Wear Resistance of Sputtered Amorphous Sicn Film and Measurement of Delamination Strength of Film by Micro Edge-Indent Method." In Experimental Analysis of Nano and Engineering Materials and Structures, 57–58. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-6239-1_27.

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10

Huang, Yuan-Ti, Tian-Fei Wang, and Yin Mei. "A Study of Internal Friction, Electric Resistance and Shape Change in Cu-Zn and Cu-Zn-Al Alloys During Phase Transformation Use Simultaneous Measurement Method." In Review of Progress in Quantitative Nondestructive Evaluation, 1611–16. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4684-5772-8_207.

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Тези доповідей конференцій з теми "Resistance measurement method"

1

Zorzano, R. "Application of the DVM method for transference of resistance values." In IEE Seminar on Measurement Dissemination by Transfer Methods. IEE, 1999. http://dx.doi.org/10.1049/ic:19990247.

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2

Sima, Karel, David Kalas, Silvan Pretl, and Ales Hamacek. "Resistance Measurement Method for IoT and Low Power Application." In 2020 43rd International Spring Seminar on Electronics Technology (ISSE). IEEE, 2020. http://dx.doi.org/10.1109/isse49702.2020.9120987.

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3

Seungje, Moon, D. Nagalingam, A. C. T. Quah, G. B. Ang, H. P. Ng, Angela Teo, N. Y. Xu, Z. H. Mai, and J. Lam. "Detection of solder bump marginal contact resistance degradation using 4-point resistance measurement method." In 2016 IEEE 23rd International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA). IEEE, 2016. http://dx.doi.org/10.1109/ipfa.2016.7564237.

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4

Eberhardt, M. "Optical Method for Sheet Resistance Measurement of Transparent Thin Films." In Society of Vacuum Coaters Annual Technical Conference. Society of Vacuum Coaters, 2014. http://dx.doi.org/10.14332/svc14.proc.1882.

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Ellis, John, and Gethn Pickard. "A method of characterising the thermal resistance of high power LEDs." In 2017 33rd Thermal Measurement, Modeling & Management Symposium (SEMI-THERM). IEEE, 2017. http://dx.doi.org/10.1109/semi-therm.2017.7896943.

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Yu, Hongyun, Rui Li, Weijian Pan, Libin Cui, Cheng Ye, Miao Qian, and Wenxian Li. "Discussion on the Measuring Method of the Electric Resistance of Screen Clothes-Shoes." In 2015 International Conference on Test, Measurement and Computational Methods. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/tmcm-15.2015.27.

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Zhang, Lingling, Huaxiang Wang, and Yanbin Xu. "A shrinkage-thresholding method for the inverse problem of Electrical Resistance Tomography." In 2012 IEEE International Instrumentation and Measurement Technology Conference (I2MTC). IEEE, 2012. http://dx.doi.org/10.1109/i2mtc.2012.6229564.

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Sir, Michal, and Ivan Feno. "Measurement Method for the Dynamic On-State Resistance of GaN Semiconductors." In 2018 2nd European Conference on Electrical Engineering and Computer Science (EECS). IEEE, 2018. http://dx.doi.org/10.1109/eecs.2018.00106.

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9

Kim, Hyeun-Su, Hyun Oh Song, and Thomas W. Kenny. "An Improved Method of Thermal Resistance Measurement for Variable Thermal Resistors." In ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33879.

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As part of the study and development of a variable thermal resistor (VTR), we present an improved thermal resistance measurement method for the VTR in the presence of unwanted signal drifting. To measure the change of thermal resistance, instead of waiting for the steady state value of the temperature signal, we repeatedly measure only the early transient part of the thermal response signal and then fit to get thermal resistance estimation. The required lengths of measurement were studied for the tests with various thermal time constants. Using this method, we performed thermal switching tests with various material pairs in contact in order to find the material pair that minimizes thermal contact resistance.
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10

Cheruparambil, Kumar R., Bakhtier Farouk, Joseph E. Yehoda, and Nelson A. Macken. "Thermal Conductivity Measurement of CVD Diamond Films Using a Modified Thermal Comparator Method." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-1109.

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Abstract Results from an experimental study on the rapid measurement of thermal conductivity of chemical-vapor-deposited (CVD) diamond films are presented. The classical thermal comparator method has been used successfully for the measurement of thermal conductivity of bulk materials having high values of thermal resistance. Using samples of known thermal conductivity, a calibration curve is prepared. With this calibration curve, the comparator can be used to determine thermal conductivity of unknown samples. We have significantly modified and extended this technique for the measurement of materials with very low thermal resistance, i.e., CVD films with high thermal conductivity. In addition to the heated probe, the modified comparator employs a thermo-electric cooling element to increase conductive heat transfer through the film. The thermal conductivity measurements are sensitive to many other factors such as the thermal contact resistances, anisotropic material properties, surrounding air currents and temperature, and ambient humidity. A comprehensive numerical model was also developed to simulate the heat transfer process for the modified comparator. The simulations were used to develop a ‘numerical’ calibration curve that agreed well with the calibration curve obtained from our measurements. The modified method has been found to successfully measure the thermal conductivity of CVD diamond films.
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Звіти організацій з теми "Resistance measurement method"

1

Cohen, Shabtai, Melvin Tyree, Amos Naor, Alan N. Lakso, Terence L. Robinson, and Yehezkiel Cohen. Influence of hydraulic properties of rootstocks and the rootstock-scion graft on water use and productivity of apple trees. United States Department of Agriculture, 2001. http://dx.doi.org/10.32747/2001.7587219.bard.

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This one year exploratory project investigated hydraulic architecture of apple dwarfing rootstocks. The hypothesis was that hydraulic conductance is correlated with rootstock vigor. A previous study of trees on three rootstocks in Israel showed that dwarfed trees used less water than un-dwarfed trees. Analysis showed that if the tree maintains leaf water potentials above minimum values, then this implies that the dwarfed trees have lower leaf conductance, which may also be the cause of dwarfing. The current project studied small 2-year old unworked rootstock trees, and full sized trees bearing commercial yields. In both cases hydraulic conductance was determined with two methods - the non-destructive evaporative flux (EF)-leaf water potential (L WP) method, and a destructive method in which water was forced through the plant at known pressure using the "high pressure flow meter" (HPFM). Detailed work allowed measurement of conductance of the rootstock-scion union. This was achieved both with the HPFM and with the EF-LWP methods, the former in the US and the latter in Israel. Direct measurements of leaf conductance were made, and carbon isotope ratios ( d ¹³ C) were determined for leaves sampled at the end of the season. The latter can indicate sustained differences in leaf conductance behavior. HPFM and EF-LWP methods did not give the same results. In the small plants results were similar in magnitude, but not significantly correlated. In large trees, EF- L WP measurements were a fraction of those obtained with the HPFM. The latter indicates that some of the xylem is not normally functional but transports water when pressurized. Additional experimental work targeted this result. Xylem was stained before and after perfusion with water at high pressure. This showed that at least for one rootstock a significant amount of xylem was blocked before perfusion. The "air method" for determining xylem vessel properties was improved and employed. Length, radius and density of xylem vessels of different rootstocks were found to be similar, and significant differences found were not clearly related to rootstock vigor. Measurements in the commercial orchard in Israel showed that the graft union in a dwarfing rootstock was a large obstacle for water transport (i.e. had a high resistance). This apparently led to low leaf conductance to water vapor, as indicated by lower d ¹³ C, which implies low internal CO ₂ concentrations. In the US orchard, d ¹³ C in 2001 was correlated with rootstock vigor, and significant differences were found in leaf conductance. However, the d ¹³ C differences were not observed in 2002, were opposite to those found in the Israeli orchard, and measurements of the graft union with the HPFM did not find large resistances. We speculate that the graft union is not necessarily a large impediment to water transport unless the scion starts to separate from the rootstock. It was concluded that significant differences in hydraulic conductance exist between different dwarfing rootstocks. These differences may be caused by differences in xylem properties and in the degree of cavitation, as well as resistance in the graft union. However, no general relationship to rootstock vigor was found. Therefore, hydraulic conductance alone cannot explain dwarfing, but may be one of two or more factors that lead to dwarfing. Future work should integrate more factors with hydraulic relations, e.g. nutrient and solute transport and production of hormones.
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2

Shmulevich, Itzhak, Shrini Upadhyaya, Dror Rubinstein, Zvika Asaf, and Jeffrey P. Mitchell. Developing Simulation Tool for the Prediction of Cohesive Behavior Agricultural Materials Using Discrete Element Modeling. United States Department of Agriculture, October 2011. http://dx.doi.org/10.32747/2011.7697108.bard.

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The underlying similarity between soils, grains, fertilizers, concentrated animal feed, pellets, and mixtures is that they are all granular materials used in agriculture. Modeling such materials is a complex process due to the spatial variability of such media, the origin of the material (natural or biological), the nonlinearity of these materials, the contact phenomenon and flow that occur at the interface zone and between these granular materials, as well as the dynamic effect of the interaction process. The lack of a tool for studying such materials has limited the understanding of the phenomena relevant to them, which in turn has led to energy loss and poor quality products. The objective of this study was to develop a reliable prediction simulation tool for cohesive agricultural particle materials using Discrete Element Modeling (DEM). The specific objectives of this study were (1) to develop and verify a 3D cohesionless agricultural soil-tillage tool interaction model that enables the prediction of displacement and flow in the soil media, as well as forces acting on various tillage tools, using the discrete element method; (2) to develop a micro model for the DEM formulation by creating a cohesive contact model based on liquid bridge forces for various agriculture materials; (3) to extend the model to include both plastic and cohesive behavior of various materials, such as grain and soil structures (e.g., compaction level), textures (e.g., clay, loam, several grains), and moisture contents; (4) to develop a method to obtain the parameters for the cohesion contact model to represent specific materials. A DEM model was developed that can represent both plastic and cohesive behavior of soil. Soil cohesive behavior was achieved by considering tensile force between elements. The developed DEM model well represented the effect of wedge shape on soil behavior and reaction force. Laboratory test results showed that wedge penetration resistance in highly compacted soil was two times greater than that in low compacted soil, whereas DEM simulation with parameters obtained from the test of low compacted soil could not simply be extended to that of high compacted soil. The modified model took into account soil failure strength that could be changed with soil compaction. A three dimensional representation composed of normal displacement, shear failure strength and tensile failure strength was proposed to design mechanical properties between elements. The model based on the liquid bridge theory. An inter particle tension force measurement tool was developed and calibrated A comprehensive study of the parameters of the contact model for the DEM taking into account the cohesive/water-bridge was performed on various agricultural grains using this measurement tool. The modified DEM model was compared and validated against the test results. With the newly developed model and procedure for determination of DEM parameters, we could reproduce the high compacted soil behavior and reaction forces both qualitatively and quantitatively for the soil conditions and wedge shapes used in this study. Moreover, the effect of wedge shape on soil behavior and reaction force was well represented with the same parameters. During the research we made use of the commercial PFC3D to analyze soil tillage implements. An investigation was made of three different head drillers. A comparison of three commonly used soil tillage systems was completed, such as moldboard plow, disc plow and chisel plow. It can be concluded that the soil condition after plowing by the specific implement can be predicted by the DEM model. The chisel plow is the most economic tool for increasing soil porosity. The moldboard is the best tool for soil manipulation. It can be concluded that the discrete element simulation can be used as a reliable engineering tool for soil-implement interaction quantitatively and qualitatively.
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Wei, Fulu, Ce Wang, Xiangxi Tian, Shuo Li, and Jie Shan. Investigation of Durability and Performance of High Friction Surface Treatment. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317281.

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The Indiana Department of Transportation (INDOT) completed a total of 25 high friction surface treatment (HFST) projects across the state in 2018. This research study attempted to investigate the durability and performance of HFST in terms of its HFST-pavement system integrity and surface friction performance. Laboratory tests were conducted to determine the physical and mechanical properties of epoxy-bauxite mortar. Field inspections were carried out to identify site conditions and common early HFST distresses. Cyclic loading test and finite element method (FEM) analysis were performed to evaluate the bonding strength between HFST and existing pavement, in particular chip seal with different pretreatments such as vacuum sweeping, shotblasting, and scarification milling. Both surface friction and texture tests were undertaken periodically (generally once every 6 months) to evaluate the surface friction performance of HFST. Crash records over a 5-year period, i.e., 3 years before installation and 2 years after installation, were examined to determine the safety performance of HFST, crash modification factor (CMF) in particular. It was found that HFST epoxy-bauxite mortar has a coefficient of thermal expansion (CTE) significantly higher than those of hot mix asphalt (HMA) mixtures and Portland cement concrete (PCC), and good cracking resistance. The most common early HFST distresses in Indiana are reflective cracking, surface wrinkling, aggregate loss, and delamination. Vacuum sweeping is the optimal method for pretreating existing pavements, chip seal in particular. Chip seal in good condition is structurally capable of providing a sound base for HFST. On two-lane highway curves, HFST is capable of reducing the total vehicle crash by 30%, injury crash by 50%, and wet weather crash by 44%, and providing a CMF of 0.584 in Indiana. Great variability may arise in the results of friction tests on horizontal curves by the use of locked wheel skid tester (LWST) due both to the nature of vehicle dynamics and to the operation of test vehicle. Texture testing, however, is capable of providing continuous texture measurements that can be used to calculate a texture height parameter, i.e., mean profile depth (MPD), not only for evaluating friction performance but also implementing quality control (QC) and quality assurance (QA) plans for HFST.
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Hansen, Peter J., and Amir Arav. Embryo transfer as a tool for improving fertility of heat-stressed dairy cattle. United States Department of Agriculture, September 2007. http://dx.doi.org/10.32747/2007.7587730.bard.

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The overall objective of the current proposal is to develop procedures to improve the pregnancy rate achieved following transfer of fresh or cryopreserved embryos produced in the laboratory into heat-stress recipients. The overall hypothesis is that pregnancy rate in heat-stressed lactating cows can be improved by use of embryo transfer and that additional gains in pregnancy rate can be achieved through development of procedures to cryopreserve embryos, select embryos most likely to establish and maintain pregnancy after transfer, and to enhance embryo competence for post-transfer survival through manipulation of culture conditions. The original specific objectives were to 1) optimize procedures for cryopreservation (Israel/US), 2) develop procedures for identifying embryos with the greatest potential for development and survival using the remote monitoring system called EmbryoGuard (Israel), 3) perform field trials to test the efficacy of cryopreservation and the EmbryoGuard selection system for improving pregnancy rates in heat-stressed, lactating cows (US/Israel), 4) test whether selection of fresh or frozen-thawed blastocysts based on measurement of group II caspase activity is an effective means of increasing survival after cryopreservation and post-transfer pregnancy rate (US), and 5) identify genes in blastocysts induced by insulin-like growth factor-1 (IGF-1) (US). In addition to these objectives, additional work was carried out to determine additional cellular determinants of embryonic resistance to heat shock. There were several major achievements. Results of one experiment indicated that survival of embryos to freezing could be improved by treating embryos with cytochalasin B to disrupt the cytoskeleton. An additional improvement in the efficacy of embryo transfer for achieving pregnancy in heat-stressed cows follows from the finding that IGF-1 can improve post-transfer survival of in vitro produced embryos in the summer but not winter. Expression of several genes in the blastocyst was regulated by IGF-1 including IGF binding protein-3, desmocollin II, Na/K ATPase, Bax, heat shock protein 70 and IGF-1 receptor. These genes are likely candidates 1) for developing assays for selection of embryos for transfer and 2) as marker genes for improving culture conditions for embryo production. The fact that IGF-1 improved survival of embryos in heat-stressed recipients only is consistent with the hypothesis that IGF-1 confers cellular thermotolerance to bovine embryos. Other experiments confirmed this action of IGF-1. One action of IGF-1, the ability to block heat-shock induced apoptosis, was shown to be mediated through activation of the phosphatidylinositol 3-kinase pathway. Other cellular determinants of resistance of embryos to elevated temperature were identified including redox status of the embryo and the ceramide signaling pathway. Developmental changes in embryonic apoptosis responses in response to heat shock were described and found to include alterations in the capacity of the embryo to undergo caspase-9 and caspase-3 activation as well as events downstream from caspase-3 activation. With the exception of IGF-1, other possible treatments to improve pregnancy rate to embryo transfer were not effective including selection of embryos for caspase activity, treatment of recipients with GnRH.and bilateral transfer of twin embryos. In conclusion, accomplishments achieved during the grant period have resulted in methods for improving post-transfer survival of in vitro produced embryos transferred into heat-stressed cows and have lead to additional avenues for research to increase embryo resistance to elevated temperature and improve survival to cryopreservation. In addition, embryo transfer of vitrified IVF embryos increased significantly the pregnancy rate in repeated breeder cows.
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