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An Optimization Criterion for Generalized Marginal Fisher Analysis on Undersampled Problems
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作者 Wu-Yi Yang Sheng-Xing Liu +1 位作者 Tai-Song Jin Xiao-Mei Xu 《International Journal of Automation and computing》 EI 2011年第2期193-200,共8页
Marginal Fisher analysis (MFA) not only aims to maintain the original relations of neighboring data points of the same class but also wants to keep away neighboring data points of the different classes.MFA can effec... Marginal Fisher analysis (MFA) not only aims to maintain the original relations of neighboring data points of the same class but also wants to keep away neighboring data points of the different classes.MFA can effectively overcome the limitation of linear discriminant analysis (LDA) due to data distribution assumption and available projection directions.However,MFA confronts the undersampled problems.Generalized marginal Fisher analysis (GMFA) based on a new optimization criterion is presented,which is applicable to the undersampled problems.The solutions to the proposed criterion for GMFA are derived,which can be characterized in a closed form.Among the solutions,two specific algorithms,namely,normal MFA (NMFA) and orthogonal MFA (OMFA),are studied,and the methods to implement NMFA and OMFA are proposed.A comparative study on the undersampled problem of face recognition is conducted to evaluate NMFA and OMFA in terms of classification accuracy,which demonstrates the effectiveness of the proposed algorithms. 展开更多
关键词 Linear discriminant analysis (LDA) dimension reduction marginal Fisher analysis (MFA) normal MFA (NMFA) orthogonal MFA (OMFA).
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Analysis of Low-Frequency Vibrational Modes and Particle Rearrangements in Marginally Jammed Amorphous Solid under Quasi-Static Shear 被引量:1
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作者 董远湘 张国华 +2 位作者 孙其诚 赵雪丹 牛晓娜 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期101-104,共4页
We present the numerical simulation results of a model granular assembly formed by spherical particles with tIertzian interaction subjected to a simple shear in the athermal quasi-static limit. The stress-strain curve... We present the numerical simulation results of a model granular assembly formed by spherical particles with tIertzian interaction subjected to a simple shear in the athermal quasi-static limit. The stress-strain curve is shown to separate into smooth, elastic branches followed by a subsequent plastic event. Mode analysis shows that the lowest-frequency vibrational mode is more localized, and eigenvalues and participation ratios of low- frequency modes exhibit similar power-law behavior as the system approaches plastic instability, indicating that the nature of plastic events in the granular system is also a saddle node bifurcation. The analysis of projection and spatial structure shows that over 75% contributions to the non-affine displacement field at a plastic instability come from the lowest-frequency mode, and the lowest-frequency mode is strongly spatially correlated with local plastic rearrangements, inferring that the lowest-frequency mode could be used as a predictor for future plastic rearrangements in the disordered system jammed marginally. 展开更多
关键词 analysis of Low-Frequency Vibrational Modes and Particle Rearrangements in marginally Jammed Amorphous Solid under Quasi-Static Shear
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An Economic Analysis and Countermeasures for Domestic Wastes in China
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作者 Zhuang Yu Xu Huan Ren Gengxin 《Ecological Economy》 2005年第4期51-55,共5页
Domestic wastes have become an importer topic of environmental protection research. From the social cost of treating domestic wastes, this article analyzes present environmental pollution caused by neglected externali... Domestic wastes have become an importer topic of environmental protection research. From the social cost of treating domestic wastes, this article analyzes present environmental pollution caused by neglected externality when we discharge domestic wastes in the method of analysis on the difference between marginal personal cost and marginal social cost; It also proves the necessity and the importance of levying pollution tax and proposes the measures of eontrolling environmental potlution caused by domestic wastes. 展开更多
关键词 environmental pollution domestic wastes marginal analysis measures
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总量思维和边际思维的差异:对医药集中采购争议多发的一种解释
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作者 陶立波 王芳旭 《中国卫生资源》 北大核心 2021年第2期123-125,共3页
基于经济学理论探讨医药集中采购决策的总量思维和医药生产供应的边际思维的差异,提出决策时对总体成本收益的判断与供应中对单位产品成本收益的判断不一致是集中采购矛盾多发的潜在原因之一,管理者和医药厂商应引起重视。
关键词 医药medicine 集中采购centralized purchasing 边际分析marginal analysis 总量gross amount 边际margin 成本cost 收益benefit
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FAULT DIAGNOSIS APPROACH FOR ROLLER BEARINGS BASED ON EMPIRICAL MODE DECOMPOSITION METHOD AND HILBERT TRANSFORM 被引量:14
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作者 YuDejie ChengJunsheng YangYu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期267-270,共4页
Based upon empirical mode decomposition (EMD) method and Hilbert spectrum, a method for fault diagnosis of roller bearing is proposed. The orthogonal wavelet bases are used to translate vibration signals of a roller b... Based upon empirical mode decomposition (EMD) method and Hilbert spectrum, a method for fault diagnosis of roller bearing is proposed. The orthogonal wavelet bases are used to translate vibration signals of a roller bearing into time-scale representation, then, an envelope signal can be obtained by envelope spectrum analysis of wavelet coefficients of high scales. By applying EMD method and Hilbert transform to the envelope signal, we can get the local Hilbert marginal spectrum from which the faults in a roller bearing can be diagnosed and fault patterns can be identified. Practical vibration signals measured from roller bearings with out-race faults or inner-race faults are analyzed by the proposed method. The results show that the proposed method is superior to the traditional envelope spectrum method in extracting the fault characteristics of roller bearings. 展开更多
关键词 Roller bearing Empirical mode decomposition(EMD) Hilbert spectrum Local Hilbert marginal spectrum Wavelet bases Envelope analysis
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Repairable Configuration Optimization Model under Two-Echelon Inventory 被引量:1
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作者 邓雅冲 贾云献 +1 位作者 范智滕 庞升 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期1063-1065,共3页
Spares inventory configuration optimization is an effective way to improve readiness and reduce life cycle cost of equipment.Through analyzing two-echelon spares support system,the METRIC model basic theory was used.A... Spares inventory configuration optimization is an effective way to improve readiness and reduce life cycle cost of equipment.Through analyzing two-echelon spares support system,the METRIC model basic theory was used.An inventory configuration optimization model of two-echelon spares support system was proposed which took the spares expected shortfall as the object and made the minimum repairable parts expected shortfall instead of the maximum spares supportability as the objective function.Marginal efficiency analysis algorithm was applied to optimizing the spares configuration and generating a rational spares inventory configuration.Finally,several examples are given to verify the model. 展开更多
关键词 repairable parts spares configuration optimization spares expected shortfall spares supportability marginal efficiency analysis algorithm
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Study on information utility 被引量:1
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作者 张东戈 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期579-582,644,共5页
Information has two aspects. One aspect is the objective one; another aspect is the subjective one. Shannon has discussed the objective aspect of information in information theory. But the subjective aspect of informa... Information has two aspects. One aspect is the objective one; another aspect is the subjective one. Shannon has discussed the objective aspect of information in information theory. But the subjective aspect of information has not been fully discussed. Someone use “Bayesian approaches” to evaluate the value of information. But in some cases it does not meet the information user's need. This paper is focus on the subjective aspect of objectively measurable information and gives formal definitions for information, information utility, and marginal information utility, normalized calculation of information utility. The information discussed in the paper has interdisciplinary nature. This work can be the foundation of many application areas. 展开更多
关键词 analysis definition of information analysis definition of information utility analysis definition of marginal information utility normalized calculation of information utility mic^nomics analysis expression of information utility information utility functions C^4ISR system evaluation.
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Comparative Methodical Assessment of Established MOSFET Threshold Voltage Extraction Methods at 10-nm Technology Node 被引量:1
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作者 Yashu Swami Sanjeev Rai 《Circuits and Systems》 2016年第13期4248-4279,共33页
Threshold voltage (V<sub>TH</sub>) is the most evocative aspect of MOSFET operation. It is the crucial device constraint to model on-off transition characteristics. Precise V<sub>TH</sub> value... Threshold voltage (V<sub>TH</sub>) is the most evocative aspect of MOSFET operation. It is the crucial device constraint to model on-off transition characteristics. Precise V<sub>TH</sub> value of the device is extracted and evaluated by several estimation techniques. However, these assessed values of V<sub>TH</sub> diverge from the exact values due to various short channel effects (SCEs) and non-idealities present in the device. Numerous prevalent V<sub>TH</sub> extraction methods are discussed. All the results are verified by extensive 2-D TCAD simulation and confirmed through analytical results at 10-nm technology node. Aim of this research paper is to explore and present a comparative study of largely applied threshold extraction methods for bulk driven nano-MOSFETs especially at 10-nm technology node along with various sub 45-nm technology nodes. Application of the threshold extraction methods to implement noise analysis is briefly presented to infer the most appropriate extraction method at nanometer technology nodes. 展开更多
关键词 Threshold Voltage Constant Current Source Technique Linear Extrapolation Technique Threshold Voltage Estimation Techniques Short Channel Effects Drift Diffusion Model Resistive Load Inverter Noise Margin analysis
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Nearest-neighbor classifier motivated marginal discriminant projections for face recognition 被引量:4
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作者 Pu HUANG Zhenmin TANG +1 位作者 Caikou CHEN Xintian CHENG 《Frontiers of Computer Science》 SCIE EI CSCD 2011年第4期419-428,共10页
Marginal Fisher analysis (MFA) is a repre- sentative margin-based learning algorithm for face recognition. A major problem in MFA is how to select appropriate parameters, k1 and k2, to construct the respective intri... Marginal Fisher analysis (MFA) is a repre- sentative margin-based learning algorithm for face recognition. A major problem in MFA is how to select appropriate parameters, k1 and k2, to construct the respective intrinsic and penalty graphs. In this paper, we propose a novel method called nearest-neighbor (NN) classifier motivated marginal discriminant projections (NN-MDP). Motivated by the NN classifier, NN-MDP seeks a few projection vectors to prevent data samples from being wrongly categorized. Like MFA, NN-MDP can characterize the compactness and separability of samples simultaneously. Moreover, in contrast to MFA, NN-MDP can actively construct the intrinsic graph and penalty graph without unknown parameters. Experimental results on the 0RL, Yale, and FERET face databases show that NN-MDP not only avoids the intractability, and high expense of neighborhood parameter selection, but is also more applicable to face recognition with NN classifier than other methods. 展开更多
关键词 dimensionality reduction (DR) face recogni-tion marginal Fisher analysis (MFA) locality preservingprojections (LPP) graph construction margin-based nearest-neighbor (NN) classifier
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Pedestrian risk analysis at uncontrolled midblock and unsignalised intersections
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作者 Kodavanti Venkata Raghavendra Ravishankar Parvathy Maheswari Nair 《Journal of Traffic and Transportation Engineering(English Edition)》 2018年第2期137-147,共11页
Transportation is defined as port to port transfer of person or goods by a medium which can be a vehicle or a person. Pedestrians being the most neglected mode of transportation in terms of safety and facility, face d... Transportation is defined as port to port transfer of person or goods by a medium which can be a vehicle or a person. Pedestrians being the most neglected mode of transportation in terms of safety and facility, face difficult situations while crossing near intersections and midblock crossings. It becomes more of a risk when the place of crossing is uncontrolled.But if behaviour of pedestrians while crossing is analysed in such conditions, it might be possible to create suitable solution to lessen the risk and ensure safety. In most of the cities, accepting suitable gaps between vehicles in uncontrolled midblock and intersection crossings pose threat to pedestrians' safety. The present study examines the safety of pedestrian crossing behaviour at midblock and unsignalised intersection crossings.Crossing time, speed, stages of crossing, number of interruptions while crossing, and the type of vehicles for which pedestrians accept the gap were extracted from the video. The tendency to show rolling gap behavior was observed and examined for different age and gender groups to analyse the risk involved in such type of crossings. The risks analysed from the study in correlation with the pedestrian demand in such uncontrolled crossings will help in design of safer pedestrian facilities. It was observed that the size of the vehicle has a significant influence on gap acceptance and crossing behaviour of pedestrians. Male pedestrians take more risks than female pedestrians in crossing unsignalized intersections. Middle aged pedestrian category poses 60.1% more chances of interrupted crossing than the other elder and young age categories of pedestrians. Male pedestrian category and the middle aged pedestrian category are more tended to accept the smallest gap between the vehicles showing a risky nature of crossing. 展开更多
关键词 Pedestrian risk analysis Risk factors Rolling gap Safety margin Stages of crossing
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Blade containment evaluation of civil aircraft engines 被引量:20
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作者 Yang Bin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期9-16,共8页
The potential hazard resulting from uncontained turbine engine rotor blade failure has always been the long-term concern of each aero engine manufacturer, and to fully contain the failed blades under critical operatin... The potential hazard resulting from uncontained turbine engine rotor blade failure has always been the long-term concern of each aero engine manufacturer, and to fully contain the failed blades under critical operating conditions is also one of the most important considerations to meet the rotor integrity requirements. Usually, there are many factors involving the engine containment capability which need to be reviewed during the engine design phases, such as case thickness, rotor support structure, blade weight and shape, etc. However, the premier method to demonstrate the engine containment capability is the fan blade-off test and margin of safety (MS) analysis. Based on a concrete engine model, this paper aims to explain the key points of aero engine containment requirements in FAR Part 33, and introduces the implementation of MS analysis and fan blade-off test in the engine airworthiness certification. Through the introduction, it would be greatly helpful to the industrial community to evaluate the engine containment capability and prepare the final test demonstration in engine certification procedure. 展开更多
关键词 AIRWORTHINESS Engine containment Fan blade-off Margin of safety analysis Method of compliance
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General moving objects recognition method based on graph embedding dimension reduction algorithm 被引量:1
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作者 Yi ZHANG Jie YANG Kun LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第7期976-984,共9页
Effective and robust recognition and tracking of objects are the key problems in visual surveillance systems. Most existing object recognition methods were designed with particular objects in mind. This study presents... Effective and robust recognition and tracking of objects are the key problems in visual surveillance systems. Most existing object recognition methods were designed with particular objects in mind. This study presents a general moving objects recognition method using global features of targets. Targets are extracted with an adaptive Gaussian mixture model and their silhouette images are captured and unified. A new objects silhouette database is built to provide abundant samples to train the subspace feature. This database is more convincing than the previous ones. A more effective dimension reduction method based on graph embedding is used to obtain the projection eigenvector. In our experiments, we show the effective performance of our method in addressing the moving objects recognition problem and its superiority compared with the previous methods. 展开更多
关键词 Moving objects recognition Adaptive Gaussian mixture model Principal component analysis Linear discriminant analysis marginal Fisher analysis
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An approach to calculating allowable watershed pollutant loads 被引量:3
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作者 Yu GUO Haifeng JIA 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第5期658-671,共14页
To improve the management of discharge pollutants loads in the reservoirs' watershed, an approach of the allowable pollutants loads calculation and its allocation, based on the water environment model, was proposed. ... To improve the management of discharge pollutants loads in the reservoirs' watershed, an approach of the allowable pollutants loads calculation and its allocation, based on the water environment model, was proposed. Establishment of the approach framework was described at first. Under the guidance of this framework, two major steps were as follows: modeling and scenario analysis were involved and should be applied to support the decision of discharge loads management; Environ- mental Fluid Dynamic Code (EFDC) model was selected as the kernel model in this framework. In modeling step, spatial discretization for establishing cell map in model, data preprocessing, parameter calibration and uncertainty analysis (which is considered as the significantly relevant factor of the margin of safety (MOS)), were conducted. As a result of the research, the model-based approach presented as a combination of estimation and precise calculation, which contributed to scenario analysis step. Some integrated modules, such as scenario simulation, result analysis and plan optimization were implemented as cycles in the scenario analysis. Finally, allowable pollutant loads under various conditions were calculated. The Chaihe Reservoir in Liaoning Province, China was used as a case study for an application of the approach described above. Results of the Chaihe reservoir water quality simulation, show good agreement with field data and demonstrated that the approach used in the present study provide an efficient and appropriate methodology for pollutant load allocation. 展开更多
关键词 Source water protection watershed manage-ment pollutants load allocation Environmental FluidDynamic Code (EFDC) modeling margin of safety statistical analysis
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Effect of atmospheric parameters on fine particulate concentration in suburban Shanghai 被引量:1
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作者 Jian Yao Wei Liu +4 位作者 Wangkun Chen Guanghua Wang Youshi Zeng Yu Huang Jun Lin 《Particuology》 SCIE EI CAS CSCD 2013年第1期48-54,共7页
A study was conducted on the effect of atmospheric parameters, including temperature, wind speed, and relative humidity, on fine particulate mass concentrations measured in Jiading District of Shanghai, China, during ... A study was conducted on the effect of atmospheric parameters, including temperature, wind speed, and relative humidity, on fine particulate mass concentrations measured in Jiading District of Shanghai, China, during the period from January 2009 to January 2010. A sensitivity analysis was applied to investigate the interaction between atmospheric parameters and particulate mass concentration. The experiment revealed that the concentration of particulates increased with particle size from 0.1 to 1.0 μm, and decreased with the increase of particle size from 1.0 to 2.5 μm. The effects of atmospheric parameters on fine mass concentrations were significantly particle size-dependent. The PM1.0-2.5 may come from the size increase of smaller particulates after moisture absorption, And the variation of concentrations of PM0.1-l.0 was mainly attributed to the accumulation of PM0.1. The ventilation index and dilution index were calcu- lated on the basis of data collected in December 2009. A correlation analysis indicated that there was a significant relation between these two indexes and the particulate concentration by examining the three particle size ranges, 0.0-0.1, 0.1-1.0, and 1,0-2.5 μm. The Spearman correlation coefficients that related the ventilation index to the concentration for the three particle size ranges were -0.45, -0.56 and -0.47, respectively, while the coefficients that related the dilution index to the concentration were -0.36, -0.42 and -0.45, respectively. 展开更多
关键词 Sensitivity analysis Correlation analysis Size distribution marginal variable
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