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Analysis of the Employment Situation of Non Private Enterprises in Various Regions of China
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作者 Junyi Wang 《Open Journal of Applied Sciences》 2024年第1期131-144,共14页
In the past 30 years, Chinese enterprises have been a hot topic of discussion and concern among the general public in terms of economic and social status, ownership structure, business mechanism, and management level.... In the past 30 years, Chinese enterprises have been a hot topic of discussion and concern among the general public in terms of economic and social status, ownership structure, business mechanism, and management level. Solving the problem of employment for the people is an important prerequisite for their peaceful living and work, as well as a prerequisite and foundation for building a harmonious society. The employment situation of private enterprises has always been of great concern to the outside world, and these two major jobs have always occupied an important position in the employment field of China that cannot be ignored. With the establishment of the market economy system, individual and private enterprises have become important components of the socialist economy, making significant contributions to economic development and social progress. The rapid development of China’s economy, on the one hand, is the embodiment of the superiority of China’s socialist market economic system, and on the other hand, it is the role of the tertiary industry and private enterprises in promoting the national economy. Since the 1990s, China’s private enterprises have become a new economic growth point for local and even national countries, and are one of the important ways to arrange employment and achieve social stability. This paper studies the employment of private enterprises and individuals from the perspective of statistics, extracts relevant data from China statistical Yearbook, uses the relevant knowledge of statistics to process the data, obtains the conclusion and puts forward relevant constructive suggestions. 展开更多
关键词 Correlation analysis of Employment numbers Factor analysis Principal Component analysis Cluster analysis
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COMPLEX NUMBER MODE APPROACH FOR REDUCING VIBRATION OF STRUCTURAL FLEXIBLE REDUNDANT ROBOT MANIPULATORS
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作者 Wu Licheng Sun Zengqi Sun Fuchun Department of Computer Science and Technology, Qinghua University Lu Zhen Yu Shouqian Zheng Hong Beijing University of Aeronautics and Astronautics 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期102-105,共4页
A complex number mode analysis approach is proposed for vibration reducing of structural flexible redundant manipulators by utilizing self motion. In the proposed approach, the self motion is evaluated to nullify th... A complex number mode analysis approach is proposed for vibration reducing of structural flexible redundant manipulators by utilizing self motion. In the proposed approach, the self motion is evaluated to nullify the modal exciting force of flexural motion, and the approach can be freely used when the degree of freedom of flexural motion is much greater than the available degree of reundancy. The availability and effectiveness of the proposed approach are demonstrated through numerical simulation with a four link spatial robotic manipulator possessing an end flexible link. 展开更多
关键词 Redundant manipulators SELF MOTION Vibration reducing Complex number mode analysis
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Feature Extraction of Fabric Defects Based on Complex Contourlet Transform and Principal Component Analysis 被引量:1
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作者 吴一全 万红 叶志龙 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期282-286,共5页
To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform (CCT) and principal component analysis (PC... To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform (CCT) and principal component analysis (PCA) is proposed.Firstly,training samples of fabric defect images are decomposed by CCT.Secondly,PCA is applied in the obtained low-frequency component and part of highfrequency components to get a lower dimensional feature space.Finally,components of testing samples obtained by CCT are projected onto the feature space where different types of fabric defects are distinguished by the minimum Euclidean distance method.A large number of experimental results show that,compared with PCA,the method combining wavdet low-frequency component with PCA (WLPCA),the method combining contourlet transform with PCA (CPCA),and the method combining wavelet low-frequency and highfrequency components with PCA (WPCA),the proposed method can extract features of common fabric defect types effectively.The recognition rate is greatly improved while the dimension is reduced. 展开更多
关键词 fabric defects feature extraction complex contourlet transform(CCT) principal component analysis(PCA)CLC number:TP391.4 TS103.7Document code:AArticle ID:1672-5220(2013)04-0282-05
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网络环境下信息计量应用实证分析 被引量:3
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作者 徐俊 王晓芳 《微计算机信息》 2010年第30期102-104,共3页
本文以布拉德福定律为理论基础对CNKI数据库中信息科学专辑的期刊进行Web下载总频次分布规律实证研究,采用区域分析法得到布拉德福曲线,分析后指出在网络信息计量中期刊Web下载总频次分布规律基本符合布拉德福定律。
关键词 网络信息计量 Web下载频次 布拉德福定律 图形分析
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Arc-length technique for nonlinear finite element analysis 被引量:9
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作者 MEMONBashir-Ahmed 苏小卒 《Journal of Zhejiang University Science》 EI CSCD 2004年第5期618-628,共11页
Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ... Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle, received wide acceptance in finite element analysis, and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades, with particular emphasis on nonlinear finite element analysis of reinforced concrete structures. 展开更多
关键词 Arc-length method Nonlinear analysis Finite element method Reinforced concrete Load-deflection path Document code: A CLC number: TU31 Arc-length technique for nonlinear finite element analysis* MEMON Bashir-Ahmed# SU Xiao-zu (苏小卒) (Department of Structural Engineering Tongji University Shanghai 200092 China) E-mail: bashirmemon@sohu.com xiaozub@online.sh.cn Received July 30 2003 revision accepted Sept. 11 2003 Abstract: Nonlinear solution of reinforced concrete structures particularly complete load-deflection response requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle received wide acceptance in finite element analysis and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades with particular emphasis on nonlinear finite element analysis of reinforced concrete structures. Key words: Arc-length method Nonlinear analysis Finite element method Reinforced concrete Load-deflection path
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Binary Decision Diagram Quantitative Analysis Method Based on Fuzzy Set Theory
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作者 于乐 姜梅 +2 位作者 刘征 李彦锋 黄洪钟 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第4期489-493,共5页
A binary decision diagram(BDD) is a data structure that is used to represent a Boolean function.Converting fault tree into BDD can effectively simplify counting processes and improve the accuracy and effectiveness of ... A binary decision diagram(BDD) is a data structure that is used to represent a Boolean function.Converting fault tree into BDD can effectively simplify counting processes and improve the accuracy and effectiveness of the results. However, due to various types of uncertainties in reliability data, we cannot obtain precise failure probabilities. In order to accurately quantify the certainties and obtain much more reliable results, we use BDD method based on fuzzy set theory for reliability quantitative analysis. In this regard, we take W-axis feeding system of heavy-duty computer numerical control(CNC) machine as a project example and adopt fuzzy BDD quantitative analysis method to analyze its reliability. The analysis results(aided by computer calculation)illustrate the effectiveness of the method proposed in this paper. 展开更多
关键词 binary decision diagram (BDD) quantitative analysis triangular fuzzy number computer numerical control (CNC) machine
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Pallister-Killian syndrome: meiosis Ⅱ non-disjunction may be the first step in the formation of isochromosome 12p 被引量:3
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作者 SHEN Jian-dong LIANG De-sheng ZHOU Zhong-min XIA Yan LONG Zhi-gao WU Ling-qian 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第23期3482-3485,共4页
Pallister-Killian syndrome (PKS) is a rare and sporadic genetic disorder due to tissue-limited mosaicism for supernumerary isochromosome 12p(i(12p)), which is usually absent or at low-level mosaicism in cultured... Pallister-Killian syndrome (PKS) is a rare and sporadic genetic disorder due to tissue-limited mosaicism for supernumerary isochromosome 12p(i(12p)), which is usually absent or at low-level mosaicism in cultured lymphocytes but present in fibroblasts. PKS was first described in adults by Pallister in 19771 and later in children by Killian and Teschler-Nicola in 1981.2 An accurate incidence is unknown. It is clinically characterized by profound mental retardation, seizures,hypotonia, supernumerary nipples, pigmentary dysplasia,diaphragmatic hernia, "coarse" face, including prominent forehead with sparse anterior scalp hair, hypertelorism,short nose with anteverted nares, flat nasal bridge, long philtrum, cleft palate and short neck. Here we report a patient with PKS, who is the first confirmed case with PKS in China's Mainland. Molecular analysis was performed to explore the formation mechanism of i(12p).The results suggest that the maternal meiosis Ⅱ sister chromatid non-disjunction was likely the first step in the formation of i(12p), followed by postzygotic mitotic centromeric misdivision. 展开更多
关键词 Pallister-Killian syndrome SNP oligonucleotide array copy number analysis short tandem repeat polymorphism fluorescence in situ hybridization meiotic non-disjunction
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Characterization of particulate matter from diesel passenger cars tested on chassis dynamometers 被引量:4
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作者 Sungwoon Jung Jaehyun Lim +4 位作者 Sangil Kwon Sangwoo Jeon Jeongsoo Kim Jongtae Lee Sunmoon Kim 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第4期21-32,共12页
Emission characterization of particle number as well as particle mass from three diesel passenger cars equipped with diesel particulate filter(DPF), diesel oxidation catalyst(DOC)and exhaust gas recirculation(EGR... Emission characterization of particle number as well as particle mass from three diesel passenger cars equipped with diesel particulate filter(DPF), diesel oxidation catalyst(DOC)and exhaust gas recirculation(EGR) under the vehicle driving cycles and regulatory cycle.Total particle number emissions(PNEs) decreased gradually during speed-up of vehicle from 17.3 to 97.3 km/hr. As the average vehicle speed increases, the size-segregated peak of particle number concentration shifts to smaller size ranges of particles. The correlation analysis with various particulate components such as particle number concentration(PNC),ultrafine particle number concentration(UFPNC) and particulate matter(PM) mass was conducted to compare gaseous compounds(CO, CO2, HC and NOx). The UFPNC and PM were not only emitted highly in Seoul during severe traffic jam conditions, but also have good correlation with hydrocarbons and NOxinfluencing high potential on secondary aerosol generation. The effect of the dilution temperature on total PNC under the New European Driving Cycle(NEDC), was slightly higher than the dilution ratio. In addition, the nuclei mode(DP: ≤ 13 nm) was confirmed to be more sensitive to the dilution temperature rather than other particle size ranges. Comparison with particle composition between vehicle speed cycles and regulatory cycle showed that sulfate was slightly increased at regulatory cycle, while other components were relatively similar. During cold start test, semivolatile nucleation particles were increased due to effect of cold environment. Research on particle formation dependent on dilution conditions of diesel passenger cars under the NEDC is important to verify impact on vehicular traffic and secondary aerosol formation in Seoul. 展开更多
关键词 Diesel passenger cars Particle number emissions Correlation analysis Particle number concentration Ultrafine particle number concentration
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Magnetically assisted gas-solid fluidization in a tapered vessel:Part II Dimensionless bed expansion scaling 被引量:2
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作者 Jordan Hristov 《Particuology》 SCIE EI CAS CSCD 2009年第3期183-192,共10页
The article presents an effort to create dimensionless scaling correlations of the overall bed porosity in the case of magnetically assisted fluidization in a tapered vessel with external transverse magnetic field. Th... The article presents an effort to create dimensionless scaling correlations of the overall bed porosity in the case of magnetically assisted fluidization in a tapered vessel with external transverse magnetic field. This is a stand of portion of new branch in the magnetically assisted fluidization recently created concerning employment of tapered vessels. Dimensional analysis based on "pressure transform" of the initial set of variables and involving the magnetic granular Bond number has been applied to develop scaling relationships of dimensionless groups representing ratios of pressures created by the fluid flow, gravity and the magnetic field over an elementary volume of the fluidized bed. Special attention has been paid on the existing data correlations developed for non-magnetic beds and the links to the new ones especially developed for tapered magnetic counterparts. A special dimensionless variable Xp = (Ar△Dbt)1/3√RgMQ combining Archimedes and Rosensweig numbers has been conceived for porosity correlation. Data correlations have been performed by power-law, exponential decay and asymptotic functions with analysis of their adequacies and accuracies of approximation. 展开更多
关键词 Fluidization Magnetization FIRST Tapered bed Dimensional analysis Pressure transform of variables Magnetic granular Bond number Rosensweig number Porosity correlations
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Evaluation of alternative surface runoff accounting procedures using SWAT model
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作者 Haw Yen Michael J.White +2 位作者 Jaehak Jeong Mazdak Arabi Jeffrey G.Arnold 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2015年第3期54-68,共15页
For surface runoff estimation in the Soil and Water Assessment Tool(SWAT)model,the curve number(CN)procedure is commonly adopted to calculate surface runoff by dynamically updating CN values based on antecedent soil m... For surface runoff estimation in the Soil and Water Assessment Tool(SWAT)model,the curve number(CN)procedure is commonly adopted to calculate surface runoff by dynamically updating CN values based on antecedent soil moisture condition(SCSI)in field.From SWAT2005 and onward,an alternative approach has become available to apply the CN method by relating the runoff potential to daily evapotranspiration(SCSII).While improved runoff prediction with SCSII has been reported in several case studies,few investigations have been made on its influence to water quality output or on the model uncertainty associated with the SCSII method.The objectives of the research were:(1)to quantify the improvements in hydrologic and water quality predictions obtained through different surface runoff estimation techniques;and(2)to examine how model uncertainty is affected by combining different surface runoff estimation techniques within SWAT using Bayesian model averaging(BMA).Applications of BMA provide an alternative approach to investigate the nature of structural uncertainty associated with both CN methods.Results showed that SCSII and BMA associated approaches exhibit improved performance in both discharge and total NO3 predictions compared to SCSI.In addition,the application of BMA has a positive effect on finding well performed solutions in the multi-dimensional parameter space,but the predictive uncertainty is not evidently reduced or enhanced.Therefore,we recommend additional future SWAT calibration/validation research with an emphasis on the impact of SCSII on the prediction of other pollutants. 展开更多
关键词 Soil and Water Assessment Tool(SWAT) curve number method Bayesian model averaging uncertainty analysis hydrology water quality
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