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Em Algorithm of the Truncated Multinormal Distribution with linear Restriction on the Variables

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 155-162页

作者： Bai-suo jin jing-jing HAN Shu DING Bai-qi MIAO Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Nanjing Research Institute of Electronics Technology Nanjing 210039 China School of Economics Hefei University of Technology Hefei 230009 China

A new expectation-maximization（EM） algorithm is proposed to estimate the parameters of the truncated multinormal distribution with linear restriction on the variables. Compared with the generalized method of moments（GMM） estimation and the maximum likelihood estimation（MLE） for the truncated multivariate normal distribution, the EM algorithm features in fast calculation and high accuracy which are shown in the simulation results. For the real data of the national college entrance exams（NCEE）, we estimate the distribution of the NCEE examinees＇ scores in Anhui, 2003, who were admitted to the university of science and technology of China（USTC）. Based on our analysis, we have also given the ratio truncated by the NCEE admission line of USTC in Anhui, 2003.

关键词： EM algorithm truncated multinormal distribution linear restriction national college entrance exams

Contribution of Root Proliferation in Nutrient-Rich Soil Patches to Nutrient Uptake and Growth of Maize

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Pedosphere 2012年第6期22卷 776-784页

作者： li Hong-Bo ZHANG Fu-suo SHEN Jian-Bo Department of Plant Nutrition China Agricultural UniversityKey Laboratory of Plant-Soil InteractionsMinistry of EducationBeijing 100193(China)

Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year field experiment was conducted to examine the comparative effects of localized application of ammonium and phosphorus (P) at early or late stages on root growth, nutrient uptake, and biomass of maize (Zea mays L.) on a calcareous soil in an intensive farming system. Localized supply of ammonium and P had a more evident effect on shoot and root growth, and especially stimulated fine root development at the early seedling stage, with most of the maize roots being allocated to the nutrient-rich patch in the topsoil. Although localized ammonium and P supply at the late stage also enhanced the fine root growth, the plant roots in the patch accounted for a low proportion of the whole maize roots in the topsoil at the flowering stage. Compared with the early stage, fine root length in the short-lived nutrient patch decreased by 44%-62% and the shoot dry weight was not different between heterogeneous and homogeneous nutrient supply at the late growth stage. Localized supply of ammonium and P significantly increased N and P accumulation by maize at 35 and 47 days after sowing (DAS); however, no significant difference was found among the treatments at 82 DAS and the later growth stages. The increased nutrient uptake and plant growth was related to the higher proportion of root length in the localized nutrient-enriched patch. The results indicated that root proliferation in nutrient patches contributed more to maize growth and nutrient uptake at the early than late stages.

关键词： biomass growth stage intensive farming system localized nutrient supply root length

Low-temperature mechanical and magnetic properties of the reduced activation martensitic steel

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Frontiers of Materials Science 2015年第3期9卷 264-271页

作者： Hui-li DING Tao ZHANG Rui GAO Xian-Pincl WANG Qian-Feng FANG Chang-Song liU jin-Ping suo Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Mechanical and magnetic properties as well as their relationship in the reduced activation martensitic （RAM） steel were investigated in the temperature range from -90℃ to 20℃. Charpy impact tests show that the ductile-to-brittle transition temperature （DBTT） of the RAM steel is about -60℃. Low-temperature tensile tests show that the yield strength, ultimate tensile strength and total elongation values increase as temperature decreases, indicating that the strength and plasticity below the DBTT are higher than those above the DBTT. The coercive field （Hc） in the scale of logarithm decreases linearly with the increasing temperature and the absolute value of the slope of InHc versus temperature above the DBTT is obviously larger than that below the DBTT, also confirmed in the T91 steel. The results indicate that the non-destructive magnetic measurement is a promising candidate method for the DBTT detection of ferromagnetic steels.

关键词： reduced activation martensitic (RAM) steel ductile-to-brittle transition temperature (DBTT) mechanical property magnetic property non-destructive detection

Short-term Cooling,Heating and Electrical Load Forecasting in Business Parks Based on Improved Entropy Method 36

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Short-term Cooling,Heating and Electrical Load Forecasting i...

Extraction of coal-tar pitch using NMP/ILs mixed solvents

第36届中国控制会议

作者： ling Cheng Yu Zhang li suo Si Shen Fang Fang Lu jin China Electrical Power Research Institute State Grid Shanghai Municipal Electric Power Company Electric Power Research Institute NARI Group Corporation/State Grid Electric Power Research Institute The School of Control and Computer Engineering North China Electric Power University

ISBN: (纸本)9781538629185

Short-term cooling,heating and electrical load forecasting in business parks is the basis of safe and economical operation of the scheduling system,and its accuracy is largely influenced by the selection of similar *** order to improve the accuracy of load forecasting,a short-term load forecasting method based on improved entropy method is *** method is used in the similar day selection and the similar day weight determination *** overcomes the drawback of traditional entropy weight method that the information transferred by entropy weight and entropy value is inconsistent when all entropy values are close to *** verification example shows that this method can not only select the most suitable similar day from the historical day,but also has a faster computing speed than the conventional intelligent algorithm.

关键词： short-term cooling heating and electrical load forecasting improved entropy method similar days

来源： cnki会议评论

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cnki会议

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Science China Chemistry 2014年第12期57卷 1760-1765页

作者： HUANG jin Cheng li Chun Shan BAI Lu NIE Yi WANG Er Qiang HE Yu Jian ZHANG suo Jiang School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing Key Laboratory of Ionic liquids Clean Process State Key Laboratory of Multiphase Complex SystemsInstitute of Process Engineering Chinese Academy of Sciences

Coal-tar pitch(CP)is a promising carbon raw material for producing needle coke,carbon fiber *** processing,the H/C ratio,ash content,and quinoline insoluble(QI)in the CP are the key factors that influence the material *** this study,NMP was selected to extract CP first;then[BMIM]Cl/NMP mixed solvent was used;and finally a series of ionic liquids(ILs)mixtures with NMP were developed for the extraction of CP to obtain the refined *** extracts were analyzed via elemental analysis,TGA,FT-IR,and *** indicate that different NMP/IL mass ratios or different kinds of ILs have impact on the extraction *** relationship of the hydrogen to carbon(H/C)ratio changed with different solvents and QI extracts were *** showed that the H/C ratios changed little between NMP extracts and could be adjusted by changing the NMP/ILs mass ratio or using different *** extracts are suitable for preparation mesophase pitch because of no ash content,low QI,and appropriate H/C *** a result,NMP can be used to refine *** addition,[BMIM]Cl is good mixed with NMP for CP extraction,because it can obtain a relatively high yield under the same extraction conditions.

关键词： coal-tar pitch ionic liquid NMP extraction H/C

Binding Capacity for Aflatoxin B_1 by Different Adsorbents

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Agricultural Sciences in China 2010年第3期9卷 449-456页

作者： li Juan-juan suo De-cheng SU Xiao-ou Institute of Quality Standard and Testing Technology for Agro-Product Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

In this article, in vitro adsorption of aflatoxin B1 （AFB1） onto different adsorbents was characterized and the result was verified by comparing the growth performance and serum protein levels of broilers exposed to aflatoxin-contamination feed. Main components of adsorbents selected were yeast cell extracts （Product A）, HSCAS （Product B）, and a mixture of yeast product and HSCAS （Product C）, respectively. A total of 240 broilers were assigned to eight treatments, and the effects of three types of adsorbents on growth performance and serum protein levels were evaluated. Results indicated that Product B had the highest in vitro affinity for AFB1, followed by Product C and Product A. Product B bound 97.69% of the AFB1 in solution in 10 min, and it remained over 96.03% in 60 min at pH 8.0. The B-AFB1 complex was much stronger than the other two complexes in vitro condition （P 〈 0.05）. Feed intake （FI） and average daily gain （ADG） decreased （P 〈 0.05） and feed gain ratio increased （P 〈0.05） in the treatment fed aflatoxin-contaminated feed versus treatment on the basal feed. Serum total protein （TP）, albumin （ALB）, and globulin （GLOB） levels were significantly decreased （P〈0.05）. Product B （0.15%） increased growth performance and improved serum protein levels, Product A and Product C were not as effective as Product B. Three adsorbents tested here had sufficient potential to AFBt in some extents and Product B could bind AFB1 more effectively than Product A and Product C. These results indicated that Product B could alleviate some of the AFBt toxic effect in broilers.

关键词： adsorbent AFB 1 absorption efficacy

Shoot Apex Demand Determines Assimilate and Nutrients Partitioning and Nutrient-uptake Rate in Tobacco Plants

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Journal of Integrative Plant Biology 2007年第11期49卷 1654-1661页

作者： Huai-Yu Yang Chun-Jian li Fu-suo Zhang The Key Laboratory of Plant Nutrition Ministry of Agriculture Key Laboratory of Plant-Soil Interactions Ministry of Education Department of Plant Nutrition China Agricultural University Beijing 100094 China

Our previous experiment revealed that apex-removed plants have larger root systems but a lower K＋-uptake rates than intact tobacco plants. Since the apex is not only a center of growth and metabolism, but also an important place of auxin synthesis and export, the aims of this study were to distinguish whether the apex demand or auxin synthesized in the apex regulates assimilate and nutrients partitioning within plant, and to explain the reason for the lower K＋-uptake rate of the apex-removed plant. In comparison with the control plant, covering the shoot apex with a black transparent plastic bag reduced net increases in dry matter and nutrients; however, the distribution of the dry matter and nutrients between shoot and roots and nutrient-uptake rates were not changed. Removal of the shoot apex shifted the dry mass and nutrients distributions to roots, and reduced the rate of nutrient uptake. Application of 1-naphthylacetic acid （NAA） could partly replace the role of the removed apex, stimulated assimilate and nutrient deposition into the treated tissue, and enhanced the reduced plasma membrane ATPase activity of roots to the control level. However, treatment of the apex-removed plants with NAA could not rescue the reduced nutrient uptake rate and the shifted assimilates and nutrients partitioning caused by excision of the apex. Higher nutrient uptake rate of the intact plants could not be explained by root growth parameters, such as total root surface area and number of root tips. The results from the present study indicate that strong apex demand determined assimilates and nutrients partitioning and nutrient-uptake rate in tobacco （Nicotiana tabacum） plants.

关键词： assimilate and nutrient partitioning auxin nutrient uptake removal of the shoot apex shoot apex demand tobacco (Nicotiana tabacum).

Phase of Two-Component Bose-Einstein Condensates with a Coupling Drive

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Communications in Theoretical Physics 2007年第5期47卷 801-804页

作者： YU Zhao-Xian jin Shuo JIAO Zhi-Yong WANG Ji-suo Department of Physics Beijing Information Science and Technology University Beijing 100101 China Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100083 China Department of Applied Physics China University of Petroleum （East China） Dongying 257061 China Department of Physics Liaocheng University Liaocheng 252059 China

By using the invariant theory, we study the phases of two-component Bose-Einstein condensates with a coupling drive under the case that the strength of the interatomic interaction in each condensate equals the interspecies interaction. The dynamical and geometric phases are presented respectively. The Aharonov-Anandan phase is also obtained under the cyclical evolution.

关键词： Bose-Einstein condensation

Microstructure and grain boundary morphology evolution of a novel Co-9Al-9W-2Ta-0.02B alloy doped with yttrium

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Rare Metals 2017年第12期36卷 951-961页

作者： Jian-Qiang Ma Fei Zhong Shu-suo li Jiang-Bo Sha School of Materials Science and Engineering Beihang University Beijing 100191 China

The microstructures and grain boundary morphologies of a novel Co-9 Al-9 W-2 Ta-0.02 B alloy doped with yttrium(Y)(0.01,0.05,0.10,and 0.20; at%) were investigated as functions of aging temperatures(900 and1000 ℃) and time(50 and 150 h). The aged alloys all exhibit a γ/γ’-Co(Al,W) coherent microstructure in grain interiors, whereas an intermetallic κ-Co(W) phase precipitates at grain boundaries. Y is found to fully segregate at grain boundaries and changes grain boundary precipitate morphologies. For 0.01 Y alloy, bright κ-Co(W) stripes precipitate along grain boundaries, where a needlelike κ-Co(W) phase grows from grain boundaries or κ-Co(W) stripes toward grain interior. As the nominal Y content increases, the stripe and needlelike κ-Co(W) precipitates at grain boundaries are strongly restrained and disappear in 0.20 Y alloy, leaving fine κ-Co(W) particles scattered at grain boundaries. It is noted that more Y segregation may increase the number of low-angle grain boundaries(LABS, with misorientations of liminates O impurities from grain boundaries. Finally,the effect of Y segregation on tensile behavior of Co-AlW-Ta-B alloy was discussed from the viewpoints of grain boundary precipitate morphologies, grain boundary character distribution(GBCD), and impurity segregation.

关键词： Intermetallics Alloy design Grain boundary segregation Casting Microstructure