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An Efficient Approach for Transforming Unbalanced Transportation Problems into Balanced Problems in Order to Find Optimal Solutions
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作者 Abdur Rashid Md. Amirul Islam 《American Journal of Operations Research》 2024年第1期74-86,共13页
In operations research, the transportation problem (TP) is among the earliest and most effective applications of the linear programming problem. Unbalanced transportation problems reflect the reality of supply chain a... In operations research, the transportation problem (TP) is among the earliest and most effective applications of the linear programming problem. Unbalanced transportation problems reflect the reality of supply chain and logistics situations where the available supply of goods may not precisely match the demand at different locations. To deal with an unbalanced transportation problem (UTP), it is essential first to convert it into a balanced transportation problem (BTP) to find an initial basic feasible solution (IBFS) and hence the optimal solution. The present paper is concerned with introducing a new approach to convert an unbalanced transportation problem into a balanced one and as a consequence to obtain optimum total transportation cost. Numerical examples are provided to demonstrate the suggested method. 展开更多
关键词 unbalanced Transportation Problem (UTP) Supply DEMAND Initial Solution Optimal Solution
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Influence and determinative factors of ion-to-atom arrival ratio in unbalanced magnetron sputtering systems 被引量:8
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作者 Jun Zhou Zhe Wu Zhanhe Liu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期775-781,共7页
Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputterin... Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputtering, by producing dense secondary plasma around the substrate, provides a high ion current density. The closed-field unbalanced magnetron sputtering system (CFUBMS) has been established as a versatile technique for high-rate deposition high-quality metal, alloy, and ceramic thin films. The'key factor in the CFUBMS system is the ability to transport high ion currents to the substrate, which can enhance the formation of full dense coatings at relatively low value homologous temperature. The investigation shows that the energy of ions incidenced at the substrate and the ratio of the flux of these ions to the flux of condensing atoms are the fundamental parameters in determining the structure and properties of films produced by ion-assisted deposition processes. Increasing ion bombardment during deposition combined with increasing mobility of the condensing atoms favors the formation of a dense microstructure and a smooth surface. 展开更多
关键词 magnetron sputtering closed-field unbalanced magnetron sputtering system (CFUBMS) ion-to-atom ratio unbalancedmagnetron sputtering
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Mitigation of Unbalanced Voltage Sags and Voltage Unbalance in CIGRE Low Voltage Distribution Network
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作者 Ghullam Mustafa Bhutto Birgitte Bak-Jensen +1 位作者 Pukar Mahat Carlo Cecati 《Energy and Power Engineering》 2013年第9期551-559,共9页
Any problem with voltage in a power network is undesirable as it aggravates the quality of the power. Power electronic devices such as Voltage Source Converter (VSC) based Static Synchronous Compensator (STATCOM) etc.... Any problem with voltage in a power network is undesirable as it aggravates the quality of the power. Power electronic devices such as Voltage Source Converter (VSC) based Static Synchronous Compensator (STATCOM) etc. can be used to mitigate the voltage problems in the distribution system. The voltage problems dealt with in this paper are to show how to mitigate unbalanced voltage sags and voltage unbalance in the CIGRE Low Voltage (LV) test network and networks like this. The voltage unbalances, for the tested cases in the CIGRE LV test network are mainly due to single phase loads and due to unbalanced faults. The compensation of unbalanced voltage sags and voltage unbalance in the CIGRE distribution network is done by using the four STATCOM compensators already existing in the test grid. The simulations are carried out in DIgSILENT power factory software version 15.0. 展开更多
关键词 Power Quality unbalanced VOLTAGE Sags MITIGATION of VOLTAGE unbalancE VOLTAGE unbalancE Factor (VUF) Distributed Static COMPENSATOR (STATCOM)
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Compensation of Unbalanced Impedance of Asymmetric Wind Power PMSG Compensated by External Circuits in Series
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作者 Yashan Hu Z.Q.Zhu Milijana Odavic 《CES Transactions on Electrical Machines and Systems》 2017年第2期180-188,共9页
The unbalanced impedance of the asymmetric 3-phase wind power permanent magnet synchronous generator(PMSG)compensated by external circuits in series with the 3-phase windings is investigated in this paper.The asymmetr... The unbalanced impedance of the asymmetric 3-phase wind power permanent magnet synchronous generator(PMSG)compensated by external circuits in series with the 3-phase windings is investigated in this paper.The asymmetric impedance includes the unbalanced resistances,unbalanced self-inductances,and unbalanced mutual inductances.From the perspective of the second harmonic inductances in dq-frame and from the perspective of the second harmonic power,it is theoretically demonstrated that the original asymmetric 3-phase system with asymmetric impedance can be modified to a balanced system by external circuits consisting of resistances and inductances.Therefore,the second harmonic power and DC bus voltage due to the asymmetries can be suppressed naturally without any software modifications.The feasibility of this compensation method is validated by elaborate experiments at different speeds and under different load condition,although the effectiveness might be slightly affected by the non-linearity of the compensation inductance in practice. 展开更多
关键词 Asymmetry compensation in series second harmonic DC bus voltage unbalance compensation unbalanced impedance
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A Survey of Unbalanced Flow Diagnostics and Their Application 被引量:23
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作者 Fuqing Zhang Steven E. Koch Christopher A. Davis and Michael L. Kaplan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期165-183,共19页
This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equatio... This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the East Coast of the United States. Comparison of these tools in this case study shows that these various methods agree to a large extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - Rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were performed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAR Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the RIP post-processing package. 展开更多
关键词 unbalanced flow Geostrophic adjustment Gravity waves Nonlinear balance equation Potential vorticity inversion Omega equations Rossby number
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LINEAR PROVABLE SECURITY FOR A CLASS OF UNBALANCED FEISTEL NETWORK 被引量:3
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作者 Wang Nianping Jin Chenhui Yu Zhaoping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期401-406,共6页
A structure iterated by the unbalanced Feistel networks is introduced. It is showed that this structure is provable resistant against linear attack. The main result of this paper is that the upper bound of r-round (r... A structure iterated by the unbalanced Feistel networks is introduced. It is showed that this structure is provable resistant against linear attack. The main result of this paper is that the upper bound of r-round (r≥2m) linear hull probabilities are bounded by q^2 when around function F is bijective and the maximal linear hull probabilities of round function F is q. Application of this structure to block cipher designs brings out the provable security against linear attack with the upper bounds of probabilities. 展开更多
关键词 unbalanced Feistel networks provable security against linear attack linear hull probabilities upper bound.
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A Nonlinear Control Strategy for Vienna Rectifier Under Unbalanced Input Voltage 被引量:1
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作者 REN Xiaoyong CHEN Yu +2 位作者 TONG Dan ZHANG Zhiliang CHEN Qianhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第5期703-714,共12页
The Vienna rectifier with unbalanced input voltage and load transient is analyzed.A nonlinear control strategy for Vienna rectifier under unbalanced input is proposed.From the view of positive and negative sequence co... The Vienna rectifier with unbalanced input voltage and load transient is analyzed.A nonlinear control strategy for Vienna rectifier under unbalanced input is proposed.From the view of positive and negative sequence components,the proposed nonlinear control strategy suppresses the twice frequency ripple and guarantees the dynamic response characteristic at the same time.Thanks to the proposed nonlinear control strategy,the DC bus capacitor can be reduced a lot since the voltage ripple and drop can be suppressed.A 10 kW Vienna rectifier is built to verify the proposed control strategy.After applying the proposed nonlinear control strategy,the voltage ripple is only7 V and decreases over 75%over the traditional PI control when the unbalanced degree is 20%.The voltage drop can be reduced about 80%than former control strategy which is helpful to reduce the DC bus capacitor and achieve higher power density.The volume of the capacitor can be reduced by 83.3%with the new control method. 展开更多
关键词 VIENNA RECTIFIER radars unbalanced INPUT voltage NONLINEAR control strategy DC BUS CAPACITANCE
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The Effect of Unbalanced Coefficient of Magnetron on the Structure and Properties of CN_x Coatings 被引量:1
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作者 文晓斌 李显 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第2期274-280,共7页
The effect of unbalanced coefficient of magnetron (UCM) on the structure and tribological properties of CrNx hard coatings was studied.The CrNx coatings were deposited on both Si wafer and hardened tool steel substr... The effect of unbalanced coefficient of magnetron (UCM) on the structure and tribological properties of CrNx hard coatings was studied.The CrNx coatings were deposited on both Si wafer and hardened tool steel substrates using a closed-field unbalanced magnetron sputtering ion plating technique in a gas mixture of Ar+N2 under different unbalanced magnetron conditions.The coatings were characterized by means of XRD,XPS,SEM,microhardness tester and pin-on-disc tribometer to study respectively their structure,chemical bonding state,microstructure,hardness and tribological properties.The experimental results show that the UCM has a profound effect on the structure,hardness and tribological properties of the CrNx coatings.With increasing the values of UCM,the dominant phases in the deposited coatings evolved from Cr+Cr2N to Cr2N+CrN,the microstructure became denser and the hardness increased;in addition,reduced coefficient of friction and improved wear resistance of CrNx coatings were also observed under a larger UCM. 展开更多
关键词 magnetron sputtering unbalanced coefficient CrNx coating structure properties
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Gyroscope Fault Diagnosis Using Fuzzy SVM to Unbalanced Samples 被引量:1
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作者 罗秋凤 张锐 +1 位作者 李勇 杨忠清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第1期16-21,共6页
A novel fuzzy support vector machine based on unbalanced samples(FSVM-US)is proposed to solve the high false positive rate problem since the gyroscope output is susceptible to unmanned aerial vehicle(UAV)airborne elec... A novel fuzzy support vector machine based on unbalanced samples(FSVM-US)is proposed to solve the high false positive rate problem since the gyroscope output is susceptible to unmanned aerial vehicle(UAV)airborne electromagnetic environment and the gyroscope abnormal signal sample is rather rare.Firstly,the standard deviation of samples projection to normal vector for SVM classifier hyper plane is analyzed.The imbalance feature expression reflecting the hyper plane shift for the number imbalance between samples and the dispersion imbalance within samples is derived.At the same time,the denoising factor is designed as the exponential decay function based on the Euclidean distance between each sample and the class center.Secondly,the imbalance feature expression and denoising factor are configured into the membership function.Each sample has its own weight denoted the importance to the classifier.Finally,the classification simulation experiments on the gyroscope fault diagnosis system are conducted and FSVM-US is compared with the standard SVM,FSVM,and the four typical class imbalance learning(CIL)methods.The results show that FSVM-US classifier accuracy is 12% higher than that of the standard SVM.Generally,FSVM-US is superior to the four CIL methods in total performance.Moreover,the FSVMUS noise tolerance is also 17% higher than that of the standard SVM. 展开更多
关键词 fault diagnosis GYROSCOPE fuzzy support vector machine(FSVM) unbalanced samples membership function
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Cu Films Deposited by Unbalanced Magnetron Sputtering Enhanced by ICP and External Magnetic Field Confinement 被引量:1
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作者 齐雪莲 任春生 +1 位作者 马腾才 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期319-322,共4页
Metallic copper(Cu) films were deposited on a Si (100) substrate by unbalanced magnetron sputtering enhanced by radio-frequency plasma and external magnetic field confinement. The morphology and structure of the f... Metallic copper(Cu) films were deposited on a Si (100) substrate by unbalanced magnetron sputtering enhanced by radio-frequency plasma and external magnetic field confinement. The morphology and structure of the films were examined by scanning electron microscopy (SEM), atomic force microscope (AFM) and X-ray diffraction (XRD). The surface average roughness of the deposited Cu films was characterized by AFM data and resistivity was measured by a four-point probe. The results show that the Cu films deposited with radio-frequency discharge enhanced ionization and external magnetic field confinement have a smooth surface, low surface roughness and low resistivity. The reasons may be that the radio-frequency discharge and external magnetic field enhance the plasma density, which further improves the ion bombardment effect under the same bias voltage conditions. Ion bombardment can obviously influence the growth features and characteristics of the deposited Cu films. 展开更多
关键词 unbalanced magnetron sputtering RADIO-FREQUENCY magnetic field Cu film
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Fabrication of Diamond-like Carbon Films by Ion Assisted Middle Frequency Unbalanced Magnetron Sputtering 被引量:1
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作者 ZHANG Yi-chen SUN Shao-ni +2 位作者 ZHOU Yi MA Sheng-ge BA De-chun 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期119-125,共7页
Diamond-like carbon (DLC) films are deposited by the Hall ion source assisted by the mid-frequency unbalanced magnetron sputtering technique. The effects of the substrate voltage bias, the substrate temperature, the... Diamond-like carbon (DLC) films are deposited by the Hall ion source assisted by the mid-frequency unbalanced magnetron sputtering technique. The effects of the substrate voltage bias, the substrate temperature, the Hall discharging current and the argon/nitrogen ratio on the DLC film's performance were studied. The experimental results show that the film's surface roughness, the hardness and the Young's modulus increase firstly and then decrease with the bias voltage incrementally increases. Also when the substrate temperature rises, the surface roughness of the film varies slightly, but its hardness and Young's modulus firstly increase followed by a sharp decrease when the temperature surpassing 120 ℃. With the Hall discharging current incrementally rising, the hardness and Young's modulus of the film decrease and the surface roughness of the film on 316L stainless steel firstly decreased and then remains constant. 展开更多
关键词 fluid machinery and engineering diamond-like carbon films middle frequency unbalanced magnetron sputtering hall ion source
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Experimental study of suppressing the unbalanced response vibration of rotor system with a G-type integral squeeze film damper 被引量:1
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作者 闫伟 He Lidong +2 位作者 Zhang Yufei Zhang Yipeng Jia Xingyun 《High Technology Letters》 EI CAS 2021年第1期1-9,共9页
Conventional squeeze film dampers have numerous challenges including lock up,bistable response and incoordinate precession.In order to resolve these nonlinear problems,a novel G-type integral squeeze film damper(GISFD... Conventional squeeze film dampers have numerous challenges including lock up,bistable response and incoordinate precession.In order to resolve these nonlinear problems,a novel G-type integral squeeze film damper(GISFD)is proposed in this research.The experimental test rig is provided to investigate the rotor system with an unbalanced single disk.Numerical simulation results show that the structural design of GISFD is reasonable,which can ensure its safe and stable operation.The influence of different support stiffnesses on the first-order speed of the rotor system is analyzed.Experimental results show that GISFD can effectively suppress the unbalanced response vibration of the rotor.In a certain range,it is found that the suppression effect of GISFD increases with the increase in the kinematic viscosity of the damping fluid.When the silicone oil with kinematic viscosity coefficients v=30.0 cm^(2)/s is employed,the vibration reduction of GISFD is approximately 71.51%.Furthermore,the experimental results show that with the increase of the unbalance,there is a linear relationship between the unbalance and the corresponding amplitude of the unbalanced response.It is concluded that GISFD has excellent linear damping characteristics and reduces the sensitivity of the rotor system to the unbalanced mass. 展开更多
关键词 G-type integral squeeze film damper(GISFD) unbalanced response vibration suppression rotor system dynamic characteristic
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Flexible Power Regulation and Limitation of Voltage Source Inverters under Unbalanced Grid Faults 被引量:1
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作者 Peng Cheng Kongyuan Li +2 位作者 Chao Wu Jing Ma Limin Jia 《CES Transactions on Electrical Machines and Systems》 CSCD 2022年第2期153-161,共9页
This paper develops a flexible power regulation and limitation strategy of voltage source inverters(VSIs)under unbalanced grid faults.When the classical power theory is used under unbalanced grid faults,the power osci... This paper develops a flexible power regulation and limitation strategy of voltage source inverters(VSIs)under unbalanced grid faults.When the classical power theory is used under unbalanced grid faults,the power oscillations and current distortions are inevitable.In the proposed strategy,the extended power theory is introduced to compute the power feedbacks together with the classical power theory.Based on the combination of the classical and extended power theory,the proposed strategy can achieve the sinusoidal current provision and the flexible regulation between three common targets,i.e.,constant active power,balanced current,and constant reactive power.Meanwhile,the proposed strategy is associated with a power limiter,which is capable to keep the currents under the pre-defined threshold and to compute the maximum apparent power for better utilization of the inverter capacity.With this power limiter,the rated inverter capacity is fully used for both the active and reactive power provisions under unbalanced grid faults.Using the proposed power regulation and limitation,the VSI can avoid overcurrent tripping and flexibly regulate its power under unbalanced grid faults.All the conclusions are verified by the real-time hardware-in-loop tests. 展开更多
关键词 Flexible power regulation Power limiter Voltage source inverter unbalanced faults
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Analysis of Variance in an Unbalanced Two-Way Mixed Effect Interactive Model 被引量:1
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作者 F. C. Eze E. U. Nwankwo 《Open Journal of Statistics》 2016年第2期310-319,共10页
The expected mean squares for unbalanced mixed effect interactive model were derived using Brute Force Method. From the expected mean squares, there are no obvious denominators for testing for the main effects when th... The expected mean squares for unbalanced mixed effect interactive model were derived using Brute Force Method. From the expected mean squares, there are no obvious denominators for testing for the main effects when the factors are mixed. An expression for F-test for testing for the main effects was derived which was proved to be unbiased. 展开更多
关键词 Mixed Model Expected Mean Squares unbalanced Data
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The Tragedy of Unbalanced Personality——The Common Personality Psychological Reasons of the Destruction of Emily and Usher
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作者 胡星 《海外英语》 2014年第16期223-224,共2页
A Rose for Emily is the masterpiece of William Faulkner, who is regarded as the founder of Southern literature. The Fall of the House of Usher is one of the most popular short stories written by the great American wri... A Rose for Emily is the masterpiece of William Faulkner, who is regarded as the founder of Southern literature. The Fall of the House of Usher is one of the most popular short stories written by the great American writer Edgar Allan Poe. They have common ends that the main characters of the two novels—Emily and Usher are all destruction of their unbalanced personality.This thesis will set a new point from a branch view of psychology—personality psychology to analyze the two characters Emily and Usher, how they change from pathological personality to abnormal personality, and finally destruct from flesh to soul. The deep meaning is to announce the human inner world will distract by the outside world. 展开更多
关键词 TRIPARTITE structural model unbalanced PERSONALITY
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Design of DSTATCOM Controller for Compensating Unbalances 被引量:1
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作者 Murugesan Kullan Ranganath Muthu +1 位作者 Jebamalai Benny Mervin Vijayenthiran Subramanian 《Circuits and Systems》 2016年第9期2362-2372,共11页
In a three phase power system, the voltages at the generation side are in sinusoidal and equal in magnitude with 120? phase difference between the phases. However, at the load side voltages may become unbalanced due t... In a three phase power system, the voltages at the generation side are in sinusoidal and equal in magnitude with 120? phase difference between the phases. However, at the load side voltages may become unbalanced due to unequal voltage magnitudes at the fundamental frequency, phase angle deviations or unequal distribution of single phase loads. The voltage unbalance is a major power quality issue, because a small unbalance in the phase voltages can cause a larger unbalance in the phase currents. A completely balanced three-phase three wire system contains only positive sequence components of voltage, current and impedance, whereas unbalanced system contains both positive and negative sequence components of voltages and currents. The negative sequence component of current in the unbalanced system increases the temperature and losses in the equipments. Hence, it is necessary to mitigate this problem by supplying the negative sequence current to the load at the load side and keep the source side balanced. This paper proposes the shunt connected, current injecting Distribution Static Synchronous Compensator (DSTATCOM) with appropriate controller to mitigate the unbalanced load current. The symmetrical components based Hysteresis Current Controller (HCC) is designed for DSTATCOM to diminish the unbalances in a three-phase three-wire system. The performance of the controller is studied by simulating the entire system in the MATLAB/Simulink environment. The DSTATCOM with HCC is found to be better than other controllers because it is suitable for compensating both balanced and unbalanced loads. 展开更多
关键词 COMPENSATION DSTATCOM Hysteresis Current Controller Symmetrical Components unbalanced Systems Negative Sequence Current
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Case Study of Unbalanced Effort Distribution in E-C Consecutive Interpreting 被引量:1
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作者 周霞 尹小飞 《海外英语》 2017年第17期96-100,共5页
Under the guidance of Daniel Gile's Effort Model, the paper makes an illustration of unbalanced effort distribution in the first phase of E-C consecutive interpretation through case studies, which are based on fie... Under the guidance of Daniel Gile's Effort Model, the paper makes an illustration of unbalanced effort distribution in the first phase of E-C consecutive interpretation through case studies, which are based on field interpretation practices. The paper explores the causes of improper effort distribution from three perspectives, namely knowledge of the language, extra-linguistic knowledge, and note-taking method. Then it renders several strategies to address improper effort distribution problems, aiming to offer some inspirations for the future field practice. 展开更多
关键词 consecutive interpreting effort model unbalanced effort distribution
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Calculation and analysis of unbalanced magnetic pulls of different stator winding setups in static eccentric induction motor
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作者 周洋 鲍晓华 +1 位作者 马明娜 王春雨 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期619-626,共8页
In large-scale electric machines, unbalanced magnetic pull (UMP) caused by eccentricity usually results in stator-rotor rub, so it is necessary to investigate the amplitude and the influencing factors. This paper ta... In large-scale electric machines, unbalanced magnetic pull (UMP) caused by eccentricity usually results in stator-rotor rub, so it is necessary to investigate the amplitude and the influencing factors. This paper takes the squirrel-cage induction motor as an example. A magnetic loop model of an induction motor is established by an analytical method. The impact of stator winding setup (parallel branch and pole pairs) on each magnetomotive force (MMF) and unbalanced magnetic pull is analyzed. Using the finite element simulation method, the spatial and time distribution of flux density of the rotor outer circle under static eccentricity is obtained, and the unbalanced magnetic pull calculation caused by static eccentricity is completed. The conclusion of the influence of stator winding on the size of unbalanced magnetic pull provides reliable gist for motor noise and vibration analysis, and especially provides an important reference for large induction motor design. 展开更多
关键词 induction motor static eccentricity unbalanced magnetic pull stator winding
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Optimized Modeling Method for Unbalanced Data in High-Level Visual Semantic Concept Classification
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作者 谭励 曹元大 +1 位作者 杨明华 贺巧艳 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期186-191,共6页
To solve the unbalanced data problems of learning models for semantic concepts, an optimized modeling method based on the posterior probability support vector machine (PPSVM) is presented. A neighborbased posterior ... To solve the unbalanced data problems of learning models for semantic concepts, an optimized modeling method based on the posterior probability support vector machine (PPSVM) is presented. A neighborbased posterior probability estimator for visual concepts is provided. The proposed method has been applied in a high-level visual semantic concept classification system and the experiment results show that it results in enhanced performance over the baseline SVM models, as well as in improved robustness with respect to high-level visual semantic concept classification. 展开更多
关键词 visual concept modeling posterior probability support vector machine unbalanced data
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Structure and Tribology Property of Carbon Nitride Films Deposited by MW-ECR Plasma Enhanced Unbalanced Magnetron Sputtering
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作者 高鹏 徐军 +3 位作者 朴勇 丁万昱 邓新绿 董闯 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第4期425-428,共4页
Carbon nitride films were deposited by a twinned microwave electron cyclotron resonance (ECR) plasma source enhanced unbalanced magnetron sputtering system. The results indicate that the structure of the films is se... Carbon nitride films were deposited by a twinned microwave electron cyclotron resonance (ECR) plasma source enhanced unbalanced magnetron sputtering system. The results indicate that the structure of the films is sensitive to the nitrogen content. The increase in the nitrogen flow ratio leads to an increase in the sp3 content and an improvement of the tribological properties. 展开更多
关键词 carbon nitride tribological property unbalanced magnetron sputtering
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