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QUALITY CONTROL OF SEMICONDUCTOR PACKAGING BASED ON PRINCIPAL COMPONENTS ANALYSIS

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 84-86页

作者： HE Shuguang qi Ershi HE Zhen NIE Bin School of Management Tianjin University Tianjin 300072 China

5 critical quality characteristics must be controlled in the surface mount and wire-bond process in semiconductor packaging. And these characteristics are correlated with each other. So the principal components analysis（PCA） is used in the analysis of the sample data firstly. And then the process is controlled with hotelling T^2 control chart for the first several principal components which contain sufficient information. Furthermore, a software tool is developed for this kind of problems. And with sample data from a surface mounting device（SMD） process, it is demonstrated that the T^2 control chart with PCA gets the same conclusion as without PCA, but the problem is transformed from high-dimensional one to a lower dimensional one, i.e., from 5 to 2 in this demonstration.

关键词： Semiconductor packaging Principal components analysis Quality control

High Photon-Number Squeezing in Strong Field Limit

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Communications in Theoretical Physics 2006年第5期45卷 929-931页

作者： qiAN Feng HUANG Hong-Bin qi Guan-Xiao Department of Physics Southeast University Nanjing 210096 China

We show that high photon-number squeezing in bright light can be generated in both lasers and optical bistabilities by the injections of a squeezed vacuum and a classical field, and the high squeezing is maintained fo... 详细信息

关键词： photon number squeezing lasers and bistabilities

Studies on the Hazardous Effects and the Maximum Allowable Concentration of Pyrophyllite Dust

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Biomedical and Environmental Sciences 1997年第4期10卷 377-386页

作者： ZHANG WEN-CHANG ZHANG qi-FEN song ZHI-FANG(Deportment of Occupotional Health, Fujian Medical University, 88 Jiaotong Road, Fuzhou 350004, China)(Division of Pneumoconiosis, Zhejiang Medical University, Yan an Road, Hangzhou 310006, China) Department of Occupational Health Fujian Medical University China.

Pyrophyllite (H2Al2,Si4 O22, ) dust (P-dust) is a mixture of silica (10-40% ), differentproportions of a luminium oxide (Al2O3 ), and various metal compounds. People with occupa-tions known to be associated with exposure to P-dust include miners, other industrial workersand persons engaged in artistic carving. Currently, little is known about pyrophyllite pneumo-coniosis from P-dust. This study was designed to investigate the hazardous effects of P-dustand to suggest a maximum allowable concentration (MAC) of the *** included four parts: (i) Occupational epidemiology surveys in 781 workersfrom 1 pyrophyllite mine (PM) and four pyrophyllite carving mills (PCM), with a registra-tion rate of 98 %. (ii) In vitro studies: Six groups of rats were expeed to different levels ofP-dust; the cytotoxicity of P-dust on rat alveolar macrophages (AM) was investigated by de-termining the potassium'content of AM and the activity levels of lactate dehydrogenase (LDH)in AM culture fluid. (iii) Mineralogical analysis of P-dust: The contents of silica (SiO2 ), alu-minium (Al), ferrum (Fe), niikel (Ni), zinc (Zn) and copper (Cu) in hath PM-dust andPCMdust were determined. (iv ) Determination of P-dust MAC: Using the life-talbemethod, an investigation of the hygiene standard of P-dust was carried out in 625 workers ex-POSed to either PM-dust or PCM-dust, uPon whom routine radiographs were *** results suggest that the risk of developing pneumoconiosis from pyrophyllite dust issignificantly higher for PM workers than for PCM workers. The prevalence rate of PCM-dustpneumoconiosis is significantly higher in men than in women. The content of SiO2 and AlO3in the mixture of P-dust is the most important factor in the etiology of pyrophyllitosis. De-pending on the different P-dust MAC values, we suggest that 2 rng/m3 and 4 mg/m' shouldbe considered as the MAC for PM-dust and PCM-dust, respectively, and 3 mg/m' fOr P-dust. We believe that establishing different hygiene standar

关键词： PCM Studies on the Hazardous Effects and the Maximum Allowable Concentration of Pyrophyllite Dust PM Zhang SiO

Assimilation of Polarimetric Radar Data Using an Ensemble Kalman Filter for the Analysis and Forecast of Tropical Storm Ewiniar(2018)

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Journal of Tropical Meteorology 2021年第2期27卷 94-108页

作者： LI Hui-qi LIU Xian-tong XIAO Hui WAN qi-lin Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China

This study explores the potential for directly assimilating polarimetric radar data(including reflectivity Z and differential reflectivity Z_(DR))using an ensemble Kalman filter(EnKF)based on the Weather Research and Forecasting model to improve analysis and forecast of Tropical Storm Ewiniar(2018).Ewiniar weakened but brought about heavy rainfall over Guangdong,China after its final *** the present study,two experiments are performed,one assimilating only Z and the other assimilating both Z and Z_(DR).Assimilation of Z_(DR)together with Z effectively modifies hydrometeor fields,and improves the forecast of the intensity,shape and position of *** of 24-hour extraordinary rainfall≥250 mm is significantly *** can also be seen in the wind fields because of cross-variable *** current study shows the possibility of applying polarimetric radar data to improve forecasting of tropical cyclones,which deserves more research in the future.

关键词： data assimilation polarimetric radar EnKF tropical cyclone heavy rainfall

The　Molecular　Shape　Effect　in　the　Separation　of　Ionic　Isomers　by　Capillary　Zone　Electrophoresis

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Chinese Chemical Letters 1996年第12期7卷 1105-1108页

作者： qi, SZ Fang, XH Huang, AJ Sun, YL BEIJING UNIV DEPT CHEMBEIJING 100871PEOPLES R CHINA

The present understanding of electrophoretic mobility cannot satisfactorily be used to explain the separation capebility of capillary zone electrophoresis for isomeric anions. A molecular shape effect concept was proposed to describe the separation mechanism for isomeric anoins with om. p-hydroxybenzoates and two food colorants. amaranth and ponceau 4R as examples.

关键词： Isomers Capillary Effect the

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论裁判员的“执法”地位与法律责任

体育学刊 2010年第2期17卷 18-22页

作者：付朝琦江西科技师范学院军体部江西南昌330038

裁判员"执法"是裁判员依据规则规定和规则精神,在体育竞赛中实施体育竞赛规则的行为和活动。裁判员在这一行为和过程中形成的社会关系和社会角色重要而独特。关于裁判员的"执法"地位有公职说、委托说、雇佣说等观点,研究较为赞同委托说... 详细信息

裁判员"执法"是裁判员依据规则规定和规则精神,在体育竞赛中实施体育竞赛规则的行为和活动。裁判员在这一行为和过程中形成的社会关系和社会角色重要而独特。关于裁判员的"执法"地位有公职说、委托说、雇佣说等观点,研究较为赞同委托说。裁判员若接受贿赂、参与赌博,在"执法"时故意歪曲规则或违背规则操纵比赛,侵犯各方利益的应追究其法律责任。

关键词：体育法学裁判员 “执法”地位法律责任

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春大豆合理播期确定动态知识模型构建

农机化研究 2025年第1期47卷 1-6页

作者：关丛鑫张伟亓立强石文强李金阳黑龙江八一农垦大学工程学院黑龙江大庆163319 黑龙江省保护性耕作工程技术研究中心黑龙江大庆163319 农业农村部大豆机械化生产重点实验室黑龙江大庆163319

为提高春大豆播种期确定的时效性和准确性,利用农田信息采集系统获取土壤墒情及环境信息,并根据大豆播种进程与适宜环境、土壤墒情同步原理,采用隶属函数方法,将播种农艺要求与播种影响因素间的关系函数化,建立春大豆合理播期确定知识模... 详细信息

为提高春大豆播种期确定的时效性和准确性,利用农田信息采集系统获取土壤墒情及环境信息,并根据大豆播种进程与适宜环境、土壤墒情同步原理,采用隶属函数方法,将播种农艺要求与播种影响因素间的关系函数化,建立春大豆合理播期确定知识模型;并利用2个不同生态点的气象与土壤温湿度等参数,结合模型决策日期与2年中各地实际播期及出苗情况,对春大豆合理播期确定模型进行了实例验证。结果表明:2021年北15、2022年北14两块试验地播期确定模型输出结果与农田实际播期分别为4月23日、4月24日与5月7日、5月10日,月度误差分别为3.33%和9.68%,模型结果准确率分别为96.67%和90.32%。模型设计结果与当前高产春大豆实际农作制度体现较好的一致性和适用性,可以为农业生产者应用信息化手段确定春大豆播种期提供技术参考。

关键词：春大豆播期知识模型农田信息决策

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Can the temperature of Ellerman Bombs be more than 10 000 K？

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Research in Astronomy and Astrophysics 2017年第4期17卷 1-6页

作者： Cheng Fang qi Hao Ming-De Ding Zhen Li School of Astronomy and Space Science Nanjing UniversityNanjing 210093China key laboratory of modern astronomy and astrophysics(nanjing university) ministry of education collaborative innovation center of modern astronomy and space exploration

Ellerman bombs （EBs） are small brightening events in the solar lower atmosphere. By their original definition, the main characteristic of EBs is the two emission bumps in both wings of chro- mospheric lines, such as Hα and Ca II 8542A lines. Up to now, most authors have found that the temperature increase of EBs around the temperature minimum region is in the range of 600-3000 K. However, with recent IRIS observations, some authors proposed that the temperature increase of EBs could be more than 10 000 K. Using non-LTE semi-empirical modeling, we investigate the line profiles, continuum emission and radiative losses for EB models with different temperature increases, and com- pare them with observations. Our result indicates that if the EB maximum temperature reaches more than 10000K around the temperature minimum region, then the resulting Hα and Call 8542A line profiles and the continuum emission would be much stronger than those of EB observations. Moreover, due to the high radiative losses, a high temperature EB compatible with observations. Thus, our study does not higher than 10 000 K. would have a very short lifetime, which is not support the proposal that EB temperatures are higher than 10 000 K.

关键词： line profiles -- Sun: photosphere -- Sun: chromosphere

DESIGN AND DEVELOPMENT OF A HIGH PERFORMANCE ANODE FOR CHLORINE-EVOLUTION

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Transactions of Nonferrous Metals Society of China 1996年第1期6卷 85-88页

作者： Tang Dian Lin Xuan Cui Xiong Yan qi Institute for Materials Research of Fuzhou University Fuzhou 350002 Fujian Research Institute of Metallurgical Industry Fuzhou 350011

The literatures were analyzed,ingredients were designed»the mono/double layered structures were *** was found that the excellent titanium anodes could be obtained by adding cobalt into the intermediate *** an anode ma... 详细信息

关键词： titanium anode cobit chlorine-evolution