Academic literature on the topic 'Coulomb efficiency'

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Journal articles on the topic "Coulomb efficiency"

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LAURITSCH, G., and P. G. REINHARD. "AN FFT SOLVER FOR THE COULOMB PROBLEM." International Journal of Modern Physics C 05, no. 01 (February 1994): 65–75. http://dx.doi.org/10.1142/s0129183194000064.

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A solution of the Coulomb problem in Fourier representation is given. The problems with the long-range parts of the Coulomb potential are circumvented by a separate handling of them. This allows the Fourier representation to develop its typical efficiency and robusteness.
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Song, P., P. Kraus, V. Kumar, and P. Dupont. "Analysis of Rigid-Body Dynamic Models for Simulation of Systems With Frictional Contacts." Journal of Applied Mechanics 68, no. 1 (June 16, 2000): 118–28. http://dx.doi.org/10.1115/1.1331060.

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The use of Coulomb’s friction law with the principles of classical rigid-body dynamics introduces mathematical inconsistencies. Specifically, the forward dynamics problem can have no solutions or multiple solutions. In these situations, compliant contact models, while increasing the dimensionality of the state vector, can resolve these problems. The simplicity and efficiency of rigid-body models, however, provide strong motivation for their use during those portions of a simulation when the rigid-body solution is unique and stable. In this paper, we use singular perturbation analysis in conjunction with linear complementarity theory to establish conditions under which the solution predicted by the rigid-body dynamic model is stable. We employ a general model of contact compliance to derive stability criteria for planar mechanical systems. In particular, we show that for cases with one sliding contact, there is always at most one stable solution. Our approach is not directly applicable to transitions between rolling and sliding where the Coulomb friction law is discontinuous. To overcome this difficulty, we introduce a smooth nonlinear friction law, which approximates Coulomb friction. Such a friction model can also increase the efficiency of both rigid-body and compliant contact simulation. Numerical simulations for the different models and comparison with experimental results are also presented.
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Qing-Yun, Chen, Shi Dong-Dong, Zhang Yuan-Jun, and Wang Yun-Hai. "Phenol degradation on novel nickel-antimony doped tin dioxide electrode." Water Science and Technology 62, no. 9 (November 1, 2010): 2090–95. http://dx.doi.org/10.2166/wst.2010.401.

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Nickel and antimony doped tin dioxide is a novel anodic material for its good performance of electrochemical ozone generation and direct electro-catalytic oxidation. Electro-catalytic oxidation of phenol on this novel nickel-antimony doped tin dioxide electrode is presented here. The morphology and composition of the electrode are characterized. The effects of applied current densities on phenol degradation rate, energy consumption and coulomb efficiency are discussed. In 0.1 M sulfuric acid, after 4 h electrolysis with current density of 25 mA cm−1, 90% phenol is removed. And with current density of 20 mA cm−1, the highest energy efficiency of 6.85 g kWh−1 and the highest coulomb efficiency of 6.87 μg C−1 are obtained. The effect of current densities on TOC removal is also discussed.
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Wen, T., G. S. Solt, and D. W. Gao. "Electrical resistance and coulomb efficiency of electrodialysis (ED) apparatus in polarization." Journal of Membrane Science 114, no. 2 (June 1996): 255–62. http://dx.doi.org/10.1016/0376-7388(96)00005-1.

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Yu, Chun Jian, Xiao Diao Huang, Cheng Gang Fang, and Ke Fang Dai. "Research on Damping and Vibration Characteristic of the Large and Precision NC Rotary Table." Advanced Materials Research 97-101 (March 2010): 1216–22. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.1216.

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According to the current situation of acicular chip and high-frequency chattering of the NC rotary table while gear milling, rigidity and damping performances of the table were analyzed and the damping program of Coulomb friction was bring up. Online test of the gear milling cutting force can be used to establish dynamic model of circumferential vibration of the table with Coulomb friction. Then mechanism of restraining gear cutting chatter by damping of Coulomb friction and acicular chip generating mechanism were exposed. Furthermore, relationship between backlash and rotary rigidity of the table was also analyzed. A kind of floating apparatus with friction damping was designed to optimize circumferential damping of the table by adjusting Coulomb friction force, which reduces the influence of high-frequency chattering on gear milling. As a result, efficiency of gear milling was increased 1.5 times and the noise was reduced from 105dB to 91dB.
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Krasny, Robert, and Lei Wang. "A treecode based on barycentric Hermite interpolation for electrostatic particle interactions." Computational and Mathematical Biophysics 7, no. 1 (December 13, 2019): 73–84. http://dx.doi.org/10.1515/cmb-2019-0006.

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AbstractA particle-cluster treecode based on barycentric Hermite interpolation is presented for fast summation of electrostatic particle interactions in 3D. The interpolation nodes are Chebyshev points of the 2nd kind in each cluster. It is noted that barycentric Hermite interpolation is scale-invariant in a certain sense that promotes the treecode’s efficiency. Numerical results for the Coulomb and screened Coulomb potentials show that the treecode run time scales like O(N log N), where N is the number of particles in the system. The advantage of the barycentric Hermite treecode is demonstrated in comparison with treecodes based on Taylor approximation and barycentric Lagrange interpolation.
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Kerr, Mark J., Andres Cuevas, and Patrick Campbell. "Limiting efficiency of crystalline silicon solar cells due to Coulomb-enhanced Auger recombination." Progress in Photovoltaics: Research and Applications 11, no. 2 (2003): 97–104. http://dx.doi.org/10.1002/pip.464.

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Yang, Bin, Jin Wang, Youyu Zhu, Kemeng Ji, Chengyang Wang, Dianbo Ruan, and Yongyao Xia. "Engineering hard carbon with high initial coulomb efficiency for practical sodium-ion batteries." Journal of Power Sources 492 (April 2021): 229656. http://dx.doi.org/10.1016/j.jpowsour.2021.229656.

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Masuda, Yoshitake, Junji Akimoto, and Kazumi Kato. "Nanoarchitectonics of Acicular Nanocrystal Assembly and Nanosheet Assembly for Lithium-Ion Batteries." Journal of Nanoscience and Nanotechnology 20, no. 5 (May 1, 2020): 3004–12. http://dx.doi.org/10.1166/jnn.2020.17443.

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Nanoarchitectonics of metal oxide nanocrystal electrodes were developed for lithium-ion batteries. The electrodes included copper nanoparticles and doped fluorine. For the acicular nanocrystals, charge–discharge reactions progressed at 1.8 V over 100 cycles at 100 and 10 μA. A 15-mmdiameter battery containing acicular nanocrystals showed capacity, coulomb efficiency, and specific capacity, respectively of 20 μAh, 98%, and ~242 mAh/g at 100 μA and 40 μAh, 99%, and 484 mAh/g at 10 μA. The TiO2/SnO2 electrode consisted of a SnO2 sheet-assembled structure with surface layers of anatase TiO2. The TiO2/SnO2 battery operated at 1.3 (100 cycles) and 1.2 (50 cycles) V at 100 and 10 μA, respectively; its capacity, coulomb efficiency, and specific capacity, respectively were 50 μAh, 98%, and 161 mAh/g at 100 μA and 200 μAh, 97–98%, and 643 mAh/g at 10 μA. The characteristic microstructure, chemical composition, and crystal faces of both materials contributed to battery performance.
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Nikhamkin, M. Sh, S. V. Semenov, G. V. Mekhonoshin, I. V. Semenova, and N. A. Sazhenkov. "Twin Shaft Rotor System Vibration Damping Experimental Investigation." Applied Mechanics and Materials 752-753 (April 2015): 918–21. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.918.

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The influence of dry friction damping on twin shaft model test rig vibration experimental investigation is presented. Experimental investigation method is devised and tested at the work. Dry and Coulomb friction damper is developed. The efficiency of damping is evaluated quantitatively via rotor shaft vibration displacements amplitude determining.
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Dissertations / Theses on the topic "Coulomb efficiency"

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Šátek, Dominik. "Teplotní závislost kapacity negativní elektrody pro sodno – iontové akumulátory." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442527.

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This work focuses on sodium-ion batteries. It describes the basic principles of accumulators, focusing more on secondary cells, their electrodes, especially negative electrodes. The work is lightly based on the basics of lithium-ion batteries. The practical part of the work is the production of negative electrodes Na2Ti3O7, which are further measured at three different temperatures. These measurements are then evaluated.
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Goodman, Johanna Karolina Stark. "The morphology and coulombic efficiency of lithium metal anodes." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53398.

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Since their commercialization in 1990, the electrodes of the lithium-ion battery have remained fundamentally the same. While energy density improvements have come from reducing the cell packaging, higher capacity electrodes are needed to continue this trend. A lithium metal anode, where the negative electrode half reaction is the plating and stripping of metallic lithium, is explored as an alternative to current graphite anodes. The specific capacity of the lithium metal anode is over ten times that of the graphite anode, making it a serious candidate to further improve the energy density of lithium batteries. Electrodeposited lithium metal forms dendrites, sharp needles that can grow across the separator and short circuit the battery. Thus, a chief goal is to alter lithium’s plating morphology. This was achieved in two separate ionic liquid electrolytes by co-depositing lithium with sodium. The co-deposited sodium is thought to block dendritic sites, leading to a granular deposit. A nucleation study confirmed that metal deposits from the ionic liquid electrolyte containing sodium, prevented dendritic growth from nucleation on, and not after dendrites had already grown. A model based on the geometry of the nuclei was used to gain insight into the effect of the solid electrolyte interface (SEI) that forms on freshly deposited lithium metal. In addition to sodium, the effect of alkaline earth metals on the lithium deposit morphology was also explored. While these metals did not deposit from the ionic liquid electrolyte, their addition also resulted in granular, dendrite free, deposits. The alkaline earth additives generally increased the overpotential for nucleating on the substrate and lowered the current density achievable. Strontium and barium showed the least of these negative effects while still providing a dendrite free deposit. A second hurdle for lithium metal anodes is the instability between the electrolyte and lithium metal. A protective SEI layer that prevents undesired side reactions is difficult to form because of the large volume change associated with cycling. Formation of a better SEI on lithium metal was attempted through the addition vinylene carbonate, which greatly improved the coulombic efficiency of lithium metal plating and stripping. The effect of gases, such as oxygen, nitrogen and carbon dioxide, on the SEI layer was also investigated. It was found that the presence of nitrogen and oxygen improved the coulombic efficiency by facilitating a thinner SEI layer. This work presents attempts at improving the lithium metal anode both by increasing the coulombic efficiency of the redox process and by eliminating dendrite growth. The coulombic efficiency was improved through the bubbling of gases and addition of organic additives but work remains to increase this value further. Dendritic growth, which poses a safety hazard, was completely eliminated by two methods: 1) co-deposition and 2) adsorption of a foreign metal. Both methods could potentially be applied to different electrolytes, making them promising methods for preventing dendritic growth in future lithium metal anodes.
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Pickering, Jason C. Pickering. "Understanding Coulombic Efficiency Limitations in an Acid-Base Energy Storage System: Mass Transport Through Nafion." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1528397906336044.

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Chakravorty, Utshab. "STUDY OF CHARACTERIZATION OF SUBMICRON COAL PARTICLES DISPERSED IN AIR AND CAPTURE OF COAL PARTICLES BY WATER DROPS IN A SCRUBBING COLUMN." UKnowledge, 2012. http://uknowledge.uky.edu/cme_etds/16.

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Present day water spray based dust removal technologies do not effectively remove respirable submicron coal and silica dust particles in the underground coal mines causing Coal worker’s pneumoconiosis (CWP). The objective of this research was to study the electrostatic charges present in the airborne coal dust in order to develop efficient water spraying based dust removal technology where water drops charged using ionic compounds and surfactants would be used to capture the oppositely charged coal particles. In an experimental scrubbing column, coal particles dispersed in an air stream by a Fluidized Bed Aerosol Generator were captured by water drops sprayed by an atomizer. Characterization studies performed using an Aerodynamic Particle Sizer and Aerosol Electrometer showed that airborne coal particles have a significant amount of positive charge with an average of 140 elementary units of charge. The capture efficiencies of the water drops evaluated were found to be higher than those predicted by previously determined mathematical models. It was predicted that apart from the effects of Brownian diffusion, interception and impaction, the effect of Coulombic attraction was present and the charge of the water drops was predicted to be between - 2 x 10-6 C and -2 x 10-4 C.
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Stefánsdóttir, Lára Kristín. "Microbial fuel cells for organic dye degradation." Thesis, KTH, Skolan för bioteknologi (BIO), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215020.

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Wales, Benjamin. "Improvements to detection efficiency and measurement accuracy in Coulomb Explosion Imaging experiments." Thesis, 2011. http://hdl.handle.net/10012/6354.

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An algorithm for extracting event information from a Coulomb Explosion Imaging (CEI) position sensitive detector (PSD) is developed and compared with previously employed schemes. The PSD is calibrated using a newly designed grid overlay and validates the quality of the described algorithm. Precision calculations are performed to determine how best the CEI apparatus at The University of Waterloo can be improved. An algorithm for optimizing coincidence measurements of polyatomic molecules in CEI experiments is developed. Predictions of improved efficiency based on this algorithm are performed and compared with experiments using a triatomic molecule. Analysis of an OCS targeted CEI experiment using highly charged Argon ions to initiate ionization is performed. The resulting measurements are presented using a variety of visualization tools to reveal asynchronous and sequential fragmentation channels of OCS3+.
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Liu, Yu-Ting, and 劉宇庭. "Device of Rapid Battery Efficiency Check by Coulomb''s Law and Voltage Measurement." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/drqf47.

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碩士
國立虎尾科技大學
光電與材料科技研究所
103
Currently battery market applications require high energy, high power and small size of the battery. The battery is driving one of the main core of high energy-consuming products. Battery development is very important. At present, the Battery Management System(BMS) battery applications has become quite important core technology. BMS is responsible for the battery pack for security monitoring, effective control and management. BMS can improve the efficiency and reliability of the battery when the vehicle is running. BMS can improve the life of the battery pack and slows cell aging rate. Characteristics and the age of the battery cell inconsistencies between. It will lead to the occurrence of battery cells connected in series overcharge or over-discharge and reduce the capacity of the battery resulting in reduced battery performance. The detection device using the Coulomb integral measurement method computing capacity of the battery. Coulomb integral method can be implemented on a variety of battery and the current average measurement error of 1%. Usually detection device to go through the complete process of charge, through the integration of voltage measurement method can effectively reduce the testing. With 3000mAh battery is detected. Normally need to spend 155 minutes to judge the effectiveness . This paper takes only 45 minutes, the user can know the battery is suitable for further use.
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Hsu, Chung-Jye, and 許仲傑. "A PWM-based DC-DC Buck Converter with High-efficiency Light Load Mode Operation and SOC Estimation Circuit Using Coulomb Counting Method with Dynamic Voltage Calibration." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/rhu4gh.

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碩士
國立中山大學
電機工程學系研究所
106
The research topics of this thesis are related to two sub-circuits in a Battery Management System of the AUV research project, which are a PWM-based DC-DC buck converter with high-efficiency light load mode operation and SOC estimated circuit using Coulomb counting method with dynamic voltage calibration. They are realized using TSMC 0.50 um CMOS High Voltage and TSMC 0.18 um CMOS processes, respectively. The first topic is meant to resolve the poor efficiency in the light load operation of PWM-based DC/DC converters. By turning off an optimal number of power MOSFETs, the switching loss is reduced such that the efficiency is enhanced effectively. Most importantly, the optimal light load efficiency is found by the derivation of analytic equations, and then justified by post-layout simulations to prove the best efficiency theoretically. The light load mode efficiency is proved to be improved by 36%, while the peak efficiency is 91.68%. Since AUV (autonomous underwater vehicle) is only operated by battery power, the correct information of SOC (state of charge) is a must for safety. Although coulomb counting method has been widely used for SOC estimation, it is suffered from the accumulative error. The consequence is that the actual battery’s capacity is far from the estimated capacity. To reduce the error therein between, the function between the battery voltage and the capacity is used to calibrate the estimated capacity. Namely, by taking the battery voltage variation into the estimation, the reliability of the SOC estimation circuit can be effectively enhanced.
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Bond, Toby Mishkin. "Improving Precision and Accuracy in Coulombic Efficiency Measurements of Lithium Ion Batteries." 2012. http://hdl.handle.net/10222/15867.

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Lithium-ion batteries have been used extensively over the past two decades in the portable consumer electronics industry. More recently, Li-ion batteries have become candidates for much larger-scale applications such as electric vehicles and energy grid storage, which impose much more stringent requirements on batteries, especially in terms of cell lifetime. In order to develop batteries with improved lifetimes, a means of quickly and accurately evaluating battery life is required. The use of coulombic efficiency (CE) is an important tool in this regard, which provides a way to quantify parasitic reactions occurring within the cell. As more stable battery chemistries are developed, the rates of parasitic reactions occurring in the cell become reduced, and differences in CE among cells become increasingly smaller. In order to resolve these differences, charger systems must be developed which can measure CE with increased precision and accuracy. This thesis investigates various ways to improve the precision and accuracy of CE measurements. Using the high-precision charger (HPC) at Dalhousie University (built in 2009) as a starting point, a new prototype charger was built with several modifications to the design of the existing HPC. The effect of each of these modifications is investigated in detail to provide a blueprint for the development of next-generation charger systems. This prototype charger shows greatly improved precision and accuracy, with CE results that are approximately four times more precise than those of the existing HPC and over an order of magnitude more precise than high-end commercially available charger systems
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Smith, Aaron. "A HIGH PRECISION STUDY OF LI-ION BATTERIES." 2012. http://hdl.handle.net/10222/14608.

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Undesired reactions in Li-ion batteries, which lead to capacity loss, can consume or produce charge at either the positive or negative electrode. For example, the formation and repair of the solid electrolyte interphase consumes Li+ and e- at the negative electrode. Electrolyte oxidation at the positive electrode allows extra electrons (with corresponding electrolyte decomposition products) to be extracted at the electrode compared to the number which could be extracted in the absence of electrolyte oxidation. High purity electrolytes, various electrolyte additives, electrode coatings and special electrode materials are known to improve cycle life and therefore must impact coulombic efficiency. Careful measurements of coulombic efficiency are needed to quantify the impact of different battery materials on cell life time in only a few charge-discharge cycles and in a relatively short time. In order to make an impact on Li-ion cells for automotive and energy storage applications, where thousands of charge-discharge cycles are required, coulombic efficiency must be measured to an accuracy and precision of at least 0.01%. An instrument designed to make high-precision coulombic efficiency measurements on Li ion batteries is described in this thesis. Such measurements can be used to detect the influence of different electrode materials, voltage ranges, cell temperature, etc. on the performance of a cell. The effects of cycle induced and time-related capacity loss can be probed using experiments carried out at different C-rates. Precision differential voltage and capacity measurements can also be used to identify the different failure mechanisms that occur in full cells.
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Book chapters on the topic "Coulomb efficiency"

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Djellali, Meriem, Mostefa Kameche, Hakima Kebaili, Abdallah Benhamou, Mustapha Bouhent, and Christophe Innocent. "Utilization of Double-Layered Hydroxides for Enhancement of Dissolved Oxygen Reduction in Microbial Fuel Cell: An Approach for the Evaluation of Coulomb Efficiency." In ICREEC 2019, 239–44. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5444-5_30.

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Zhang, Ji-Guang, Wu Xu, and Wesley A. Henderson. "High Coulombic Efficiency of Lithium Plating/Stripping and Lithium Dendrite Prevention." In Lithium Metal Anodes and Rechargeable Lithium Metal Batteries, 45–152. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-44054-5_3.

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Kumar, Yugal, and Gadadhar Sahoo. "Application of Charge System Search Algorithm for Data Clustering." In Handbook of Research on Emerging Perspectives in Intelligent Pattern Recognition, Analysis, and Image Processing, 383–99. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-8654-0.ch018.

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This chapter presents a charged system search (CSS) optimization method for finding the optimal cluster centers for a given dataset. In CSS algorithm, while the Coulomb and Gauss laws from electrostatics are applied to initiate the local search, global search is performed using Newton second law of motion from mechanics. The efficiency and capability of the proposed algorithm is tested on seven datasets and compared with existing algorithms like K-Means, GA, PSO and ACO. From the experimental results, it is found that the proposed algorithm provides more accurate and effective results in comparison to other existing algorithms.
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Fanizzi, Nicola, Claudia d’Amato, and Floriana Esposito. "Inductive Classification of Semantically Annotated Resources through Reduced Coulomb Energy Networks." In Semantic Services, Interoperability and Web Applications, 322–42. IGI Global, 2011. http://dx.doi.org/10.4018/978-1-60960-593-3.ch013.

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The tasks of resource classification and retrieval from knowledge bases in the Semantic Web are the basis for a lot of important applications. In order to overcome the limitations of purely deductive approaches to deal with these tasks, inductive (instance-based) methods have been introduced as efficient and noise-tolerant alternatives. In this paper we propose an original method based on a non-parametric learning scheme: the Reduced Coulomb Energy (RCE) Network. The method requires a limited training effort but it turns out to be very effective during the classification phase. Casting retrieval as the problem of assessing the class-membership of individuals w.r.t. the query concepts, we propose an extension of a classification algorithm using RCE networks based on an entropic similarity measure for OWL. Experimentally we show that the performance of the resulting inductive classifier is comparable with the one of a standard reasoner and often more efficient than with other inductive approaches. Moreover, we show that new knowledge (not logically derivable) is induced and the likelihood of the answers may be provided.
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Mamaghani, Iraj H. P. "Application of Discrete Finite Element Method for Analysis of Unreinforced Masonry Structures." In Computational Modeling of Masonry Structures Using the Discrete Element Method, 440–58. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-5225-0231-9.ch017.

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In this chapter, through some illustrative examples, the applicability of the Discrete Finite Element Method (DFEM) to analysis of unreinforced masonry structures such as rock pillars, open rock slopes, underground openings, tunnels, fault propagations, and fault-structure interactions is examined and discussed. In the numerical study, the behavior of contacts and blocks is assumed to be elasto-plastic or elastic. The Mohr-Coulomb yield criterion, representing material behavior of contacts, is implemented in the developed codes for DFEM used in the analysis. The secant stiffness method with the updated Lagrangian scheme is employed to deal with non-linear behavior. The constant strain triangular element with two degrees of freedoms at each node, formed by properly joining the corners and contact nodes of an individual block, is adopted for finite element meshing of the blocks. The DFEM provides an efficient and promising tool for designing, analyzing, and studying the behavior of unreinforced masonry structures.
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Gautam, Budhayash. "Energy Minimization." In Homology Molecular Modeling - Perspectives and Applications [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94809.

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The energetic state of a protein is one of the most important representative parameters of its stability. The energy of a protein can be defined as a function of its atomic coordinates. This energy function consists of several components: 1. Bond energy and angle energy, representative of the covalent bonds, bond angles. 2. Dihedral energy, due to the dihedral angles. 3. A van der Waals term (also called Leonard-Jones potential) to ensure that atoms do not have steric clashes. 4. Electrostatic energy accounting for the Coulomb’s Law m protein structure, i.e. the long-range forces between charged and partially charged atoms. All these quantitative terms have been parameterized and are collectively referred to as the ‘force-field’, for e.g. CHARMM, AMBER, AMBERJOPLS and GROMOS. The goal of energy Minimization is to find a set of coordinates representing the minimum energy conformation for the given structure. Various algorithms have been formulated by varying the use of derivatives. Three common algorithms used for this optimization are steepest descent, conjugate gradient and Newton–Raphson. Although energy Minimization is a tool to achieve the nearest local minima, it is also an indispensable tool in correcting structural anomalies, viz. bad stereo-chemistry and short contacts. An efficient optimization protocol could be devised from these methods in conjunction with a larger space exploration algorithm, e.g. molecular dynamics.
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Conference papers on the topic "Coulomb efficiency"

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Kramer, Ronny, and Gudula Runger. "Performance and efficiency investigations of SIMD programs of Coulomb solvers on multi-and many-core systems with vector units." In 2020 28th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (PDP). IEEE, 2020. http://dx.doi.org/10.1109/pdp50117.2020.00044.

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Ferri, Aldo A., and Bonnie S. Heck. "Analysis of Stick-Slip Motion in Coulomb Damped Systems Using Variable Structure System Theory." In ASME 1997 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/detc97/vib-3915.

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Abstract The numerical simulation and control design of many systems is hampered by the presence of dry (Coulombic) friction. In particular, the discontinuous nature of the friction law leads to computational difficulties whenever sticking occurs across the frictional interfaces. This paper uses results from Variable Structure System (VSS) theory to develop a model useful for simulating stick-slip motion in a generic system with multiple frictional interfaces. The Variable Structure framework is also used to analyze the errors incurred in the new simulation model. A second approach, motivated by the alleviation of chatter in VSS systems, uses a saturation-type nonlinearity to represent the frictional interface. The accuracy of this approach is analyzed using VSS and singular perturbation theory. The accuracy and numerical efficiency of each method is demonstrated in two numerical examples.
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Guoliang Wu, Rengui Lu, Chunbo Zhu, and C. C. Chan. "An improved Ampere-hour method for battery state of charge estimation based on temperature, coulomb efficiency model and capacity loss model." In 2010 IEEE Vehicle Power and Propulsion Conference (VPPC). IEEE, 2010. http://dx.doi.org/10.1109/vppc.2010.5729017.

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Rincon, Liz K., and Joa˜o M. Rosario. "Influence of Nonlinear Friction and Disturbance in the Control of a Mechatronic System: CNC Machine Tool Application." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-48553.

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The CNC (Computer Numerical Control) machine tools are complex mechatronic systems applied to the manufacture with high precision and high speeds. To achieve high accuracy and operational efficiency, the disturbance and friction, which occur during machining process, should be reduced as low as possible. This paper develops an analysis of influence by cutting force and friction effect in the control of machine tool based on the CNC dynamic model and parameters identification. For this purpose, the study focuses on Coulomb and Viscous nonlinear friction and the external disturbances. The analysis uses control position error, contour error, and stability to determine the influence of friction and disturbance. The results show that Viscous friction has more critical influence on system than the Cutting force and Coulomb. The work contributes in recognizing which parameters have greater influence on the machine behavior through dynamic analysis with the identification strategy, in order to design and improve the control structure for a real CNC system.
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Wang, Gou-Jen, Ying-Hsu Lin, His-Harng Yang, and Cheng-Tang Pan. "Design and Fabrication of a High Efficiency Piezoelectric Vibration-Induced Micro Power Generator." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-42682.

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To fulfill the increasing self-power demanding of the embedded and remote microsystems, theoretical and experimental study of a piezoelectric vibration-induced micro power generator that can convert mechanical vibration energy into electrical energy is presented. A complete energy conversion model regarding the piezoelectric transducer is discussed first. To verify the theoretical analysis, two clusters of transducer structures are fabricated. The piezoelectric lead zirconate titanate (PZT) material that has better energy conversion efficiency among the piezoelectric materials is chosen to make of the energy conversion transducer. The desired shape of the piezoelectric generator with its resonance frequency in accordance with the ambient vibration source is designed by finite element analysis (FEA) approach. Conducting wires and load resistor are soldered on the electrodes to output and measure the vibration induced electrical power. Experimental results shows that the maximum output voltages are generated at the first mode resonance frequencies of the structure. It is also found from the experimental results that the induced voltage is irrelevant to the width of the structure but is inverse proportion to the length of the structure. It takes 7 minutes to charge a 10,000 μF capacitors array to a 7 V level. The total amount of electricity and energy stored in the capacitors are 0.7 Coulomb and 0.245 J, respectively. The experimental results are coincidence with the theoretical analysis.
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6

Kim, Sung-Jae, Weoncheol Koo, and Chul H. Jo. "Assessment of Latching Control for the Hemispheric Heaving Buoy Type Point Absorber With and Without Nonlinear Froude-Krylov Force Acting on the Buoy." In ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-96055.

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Abstract In this study, a latching control strategy was utilized to increase the efficiency of a heaving buoy-type point absorber with a hydraulic Power take-off (PTO) system. For this purpose, the hydrodynamic performance of a floating buoy was analyzed based on the potential flow theory and Cummins equation. Nonlinear Froude-Krylov (FK) force according to instantaneous wetted surface of a buoy was calculated by a theoretical solution. The effect of the latching control on a point absorber was evaluated by considering PTO performance with hydrodynamic coefficients including nonlinear FK force. The hydraulic PTO system was modeled as an approximate coulomb damping force.
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7

Quinn, D. Dane. "A New Regularization of Coulomb Friction." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32402.

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We present a new regularization for Coulomb’s law of friction for single point contacts. This modification permits a straightforward application of friction within existing numerical simulations. Similar to existing regularizations, the proposed modification to Coulomb frictions leads to continuous representation of friction and does not require the separate identification of transitions between slip and stick. However, unlike more common regularizations, the current reformulation maintains an equilibrium structure identical to the classical, discontinuous form of Coulomb friction. The implementation and performance of this regularization is illustrated by a simple one degree-of-freedom system in which stick-slip motion induced by sliding friction is of primary importance. The simulations illustrate the existence of non-trivial equilibrium states and the ability of the current regularization toprovide a computationally efficient scheme for simulating the dissipation arising from sliding friction.
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8

Yildiz, Cagkan, Tamer M. Wasfy, Hatem M. Wasfy, and Jeanne M. Peters. "Effect of Material and Geometric Parameters on the Steady-State Belt Stresses and Belt Slip for Flat Belt-Drives." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47147.

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In order to accurately predict the fatigue life and wear life of a belt, the various stresses that the belt is subjected to and the belt slip over the pulleys must be accurately calculated. In this paper, the effect of material and geometric parameters on the steady-state stresses (including normal, tangential and axial stresses), average belt slip for a flat belt, and belt-drive energy efficiency is studied using a high-fidelity flexible multibody dynamics model of the belt-drive. The belt’s rubber matrix is modeled using three-dimensional brick elements and the belt’s reinforcements are modeled using one dimensional truss elements. Friction between the belt and the pulleys is modeled using an asperity-based Coulomb friction model. The pulleys are modeled as cylindrical rigid bodies. The equations of motion are integrated using a time-accurate explicit solution procedure. The material parameters studied are the belt-pulley friction coefficient and the belt axial stiffness and damping. The geometric parameters studied are the belt thickness and the pulleys’ centers distance.
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Wasfy, Tamer M., and Hatem M. Wasfy. "Effect of Rubber Material Properties on Steady-State Flat Belt Response." In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-98166.

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Abstract Belt-drives are used to transmit power between rotational machine elements in many mechanical systems such as industrial machines, home appliances, and internal combustion engines. The belt cross-section typically consists of axially stiff tension cords (made of steel or polyester strands) embedded in a rubber matrix. The rubber matrix provides the friction interface between the belt and the pulleys through which mechanical torque is transmitted. In this paper, the effect of the rubber’s Young’s modulus and Poisson’s ratio on the steady-state belt normal, tangential and axial stresses, average belt slip, and belt-drive energy efficiency is studied using a high-fidelity flexible multibody dynamics model of a flat belt-drive. The belt’s rubber matrix is modeled using three-dimensional brick elements and the belt’s cords are modeled using one dimensional truss elements. Friction between the belt and the pulleys is modeled using an asperity-based Coulomb friction model. The pulleys are modeled as rigid bodies with a cylindrical contact surface. The equations of motion are integrated using a time-accurate explicit solution procedure.
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10

Jiang, Jing, Hong-Yue Zhao, Jin-Cheng Ding, Hong-Hao Yue, and Xu-Yan Hou. "Study on a Photovoltaic Lunar Dust Removal System Based on the Photovoltaic Effect of PLZT." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70706.

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The deposition of lunar dust on the surface of solar panels and optical elements is one of the most important problems need to be solved in lunar exploration. This paper will propose an initiative lunar dust removal system based on the photovoltaic effect of PbLaZrTi (PLZT), which is activated by the ultraviolet light extracted from sun light at the lunar surface. When ultraviolet light with a wavelength near 365nm illuminates on polarized PLZT materials, high voltages of several kilovolt per centimeter can be generated between two electrodes of PLZT. When two electrodes of PLZT are connected to a lunar dust collector (LDC) and the ITO film of protected surface respectively, an electrostatic field forms between LDC and the protected surface. Coulomb forces over particles will overcome gravitational force and surface forces, so the particles can be absorbed to LDC and removed by LDC finally. Based on the equivalent electrical model, mathematical model of electrostatic force is derived when the lunar removal electric field is acted either by single piece PLZT or by multi-pieces PLZT which are connected in parallel. Experimental platform is set up to prove the feasibility of this lunar dust removal system. In order to improve the removal efficiency, a novel configuration design of LDC based on multi-PLZT patched is proposed and its removal efficiency is evaluated by experiments.
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