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A machine learning approach to query generation in plagiarism source retrieval

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1556-1572页

作者： Lei-lei KONG zhi-mao LU Hao-liang QI zhong-yuan HAN College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China School of Computer Science and Technology Heilongjiang Institute of Technology Harbin 150050 China State Key Laboratory of Digital Publishing Technology Beijing 100871 China

Plagiarism source retrieval is the core task of plagiarism detection. It has become the standard for plagiarism detection to use the queries extracted from suspicious documents to retrieve the plagiarism sources. Generating queries from a suspicious document is one of the most important steps in plagiarism source retrieval. Heuristic-based query generation methods are widely used in the current research. Each heuristic-based method has its own advantages, and no one statistically outperforms the others on all suspicious document segments when generating queries for source retrieval. Further improvements on heuristic methods for source retrieval rely mainly on the experience of experts. This leads to difficulties in putting forward new heuristic methods that can overcome the shortcomings of the existing ones. This paper paves the way for a new statistical machine learning approach to select the best queries from the candidates. The statistical machine learning approach to query generation for source retrieval is formulated as a ranking framework. Specifically, it aims to achieve the optimal source retrieval performance for each suspicious document segment. The proposed method exploits learning to rank to generate queries from the candidates. To our knowledge, our work is the first research to apply machine learning methods to resolve the problem of query generation for source retrieval. To solve the essential problem of an absence of training data for learning to rank, the building of training samples for source retrieval is also conducted. We rigorously evaluate various aspects of the proposed method on the publicly available PAN source retrieval corpus. With respect to the established baselines, the experimental results show that applying our proposed query generation method based on machine learning yields statistically significant improvements over baselines in source retrieval effectiveness.

关键词： Plagiarism detection Source retrieval Query generation Machine learning Learning to rank

Emergency Supply Chain Management Based on Rough Set-House of Quality

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International Journal of Automation and computing 2019年第3期16卷 297-309页

作者： yuan He Xue-Dong liang Fu-min Deng zhi Li Business School Sichuan University

Due to the frequent occurrence of various emergencies in recent years,people have put forward higher requirements on the emergency supply chain *** is of great significance to explore the key management indicators of emergency supply chain for its management and efficient *** order to reveal the essence of emergency supply chain management,production,procurement,distribution,storage,use,recycling and other emergencies,supply chain links are considered to establish an emergency supply chain management index system to identify the key influencing factors in the emergency supply *** emergency supply chain involves many management elements and the traditional qualitative analysis and comprehensive evaluation methods have their shortcomings in *** order to get a more suitable method,a novel evaluation model is proposed,based on Rough set—house of quality *** this paper,Rough set is used to filter the indexes,eliminate redundant indicators,and simplify many management indicators of the emergency supply chain system to a few core ***,the house of quality is used to analyze and sort the core index to get the key management index of emergency supply *** effectiveness of the proposed evaluation model is validated through a series of numerical *** experimental results also show that the proposed evaluation model can assist decision makers in optimizing the emergency supply chain procedure and improving the efficiency of accident rescue.

关键词： Emergency supply chain Rough set House of quality management indicators attribute reduction

ESTIMATION OF DIRECTIONAL SPECTRUM AND REFLECTED COEFFICIENT OF INCIDENT AND REFLECTED WAVE IN PHASE-LOCKED WAVE FIELD

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Journal of Hydrodynamics 2005年第6期17卷 713-723页

作者： SHAO Li-min YU zhi-liang yuan Qun-zhe YU Yu-xiu Department of Ocean and Mapping Science Dalian Naval Academy Dalian 116018 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China

This paper analyses and compares the property of the Modified Bayesian Directional spectrum analysis Method （MBDM） and the Modified Maximum Lkelihood Method （MMLM） that can he used to estimate directional spectrum and reflected coefficient of phase-locked wave field overlapped by multi directional irregular incident and reflected waves. The numerical test verifies the results under different wave conditions, different measurement systems, and different reflection features. The computation speed and stability of the two methods is also compared. The analysis addresses that the MBDM is better than the MMLM for directional spectrum estimating, while the MMLM is better than the MBDM for reflected coefficient estimation and calculating speed and stability.

关键词： directional spectrum reflected coefficient,Modified Maximum Likelihood Method (MMLM) Modified Bayesian Directional spectrum analysis Method (MBDM)

Synthesis and biological evaluation of ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylates against Eimeria tenella

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Chinese Chemical Letters 2010年第4期21卷 426-428页

作者： Zhang, yuan yuan Zeng, Xing Yan Nie, Kui zhong, zhi Cheng Wang, Yu liang Wang, Yu zhong Sichuan Univ Dept Chem Chengdu 610064 Peoples R China Sichuan Univ Dept Chem Engn Chengdu 610065 Peoples R China Southwest Univ Coll Anim Sci & Technol Chongqing 400715 Peoples R China

A series of ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylates were designed and *** structures were confirmed by ~1H NMR,^(13)C NMR,IR and *** biological activities were primarily evaluated against Eimeria tenella according to Anticoccidial Index(ACI) method in *** results showed that compounds 5e,5f and 5i exhibited anticoccidial activities against *** at 27 mg kg^(-1).

关键词： Ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylate Synthesis Anticoccidial activity Eimeria tenella

Relationship between Crystal Structure of Inclusions and Formation of Acicular Ferrites

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Journal of Iron and Steel Research International 2016年第6期23卷 586-592页

作者： zhi-min CUI Li-guang ZHU yuan-liang LI Qing-jun ZHANG Chun-liang YAN Wen-ling MO School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Analysis and Testing Center North China University of Science and Technology College of Metallurgy and Energy North China University of Science and Technology Hebei Provincial Key Laboratory of Inorganic Nonmetallic Materials North China University of Science and Technology Yi Sheng College North China University of Science and Technology

The formation mechanism of intragranular ferrites with acicular morphology was *** ferrites were characterized by scanning electron *** results showed that the ferrites had an acicular structure with radial,symmetrical,and acicular laths,and that the inclusions were the nucleation sites of the intragranular acicular *** electron microscopy（TEM）was used to characterize the *** results of TEM with energy dispersive spectroscopy and TEM-selected area electron diffraction indicated that the complex inclusions consisted of Ti-Al complex oxides and *** jagged edges of the complex inclusions can be ascribed to the effects of the crystal *** stabilization energy U of the coordination polyhedron growth units varies with the type of connection according to the calculation results.A larger Ucorresponds to more stable growth units,which induces the preferentially oriented growth of inclusions,at which point acicular ferrites are formed.

关键词： nucleation dispersive preferentially stabilization characterize rutile ferrite anatase grains symmetrical

Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen electrochemistry

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1550-1560页

作者： Rui-Qi Zhang Ang Ma Xiang liang Li-min Zhao Hui Zhao zhong-Yong yuan School of Materials Science and Engineering Liaocheng UniversityLiaocheng252000China Key Laboratory of Advanced Energy Materials Chemistry(ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin3000350China

The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy *** this work,cobalt nanoparticle decorated N-doped carbons(Co@NC)are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert *** Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles,indicating the important role of *** well-dispersed active sites(Co-Nx)and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction *** addition,the Co content has a significant effect on the catalytic *** resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential(0.90 V),half-wave potential(0.80 V)and the limiting current density(4.84 mA·cm^(−2)),and a high selectivity,as well as a strong methanol tolerance and superior durability,these results are comparable to those of the Pt/C ***,the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built Zn-air battery,signifying the possibility for application in electrode materials and in current energy conversion and storage devices.

关键词： cobalt embedment N-doped carbons covalent organic framework oxygen reduction Zn-air battery

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铁基氧化物团簇催化CO还原NO反应模拟

原子与分子物理学报 2025年第6期42卷 22-30页

作者：刘众元孔繁宇陈琳梁五洲刘志兵高义斌国网山西省电力公司电力科学研究院太原030001 太原理工大学太原030024

固定床实验表明,在深度欠氧的条件下,铁基氧化物对CO还原NO的反应具有催化作用.为进一步理解脱销催化反应机理,本文利用量化软件Gaussian模拟了铁及其三种不同价态氧化物团簇:Fe_(2)团簇、Fe_(2)O_(2)团簇、Fe_(2)O_(3)团簇催化CO还原N... 详细信息

固定床实验表明,在深度欠氧的条件下,铁基氧化物对CO还原NO的反应具有催化作用.为进一步理解脱销催化反应机理,本文利用量化软件Gaussian模拟了铁及其三种不同价态氧化物团簇:Fe_(2)团簇、Fe_(2)O_(2)团簇、Fe_(2)O_(3)团簇催化CO还原NO的反应路径,为进一步改进脱硝反应提供理论基础.本文分析了反应过程的各阶段能量壁垒,三种团簇中最容易发生催化反应的团簇为Fe_(2),整个反应过程中的决速步为NO在Fe_(2)团簇上的解离吸附过程.

关键词：铁团簇脱硝模拟反应机理

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Mesenchymal stem cells from human umbilical cord ameliorate testicular dysfunction in a male rat hypogonadism model

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Asian Journal of Andrology 2017年第5期19卷 543-547页

作者： zhi-yuan Zhang Xiao-Yu Xing Guan-Qun Ju liang zhong Jie Sun Department of Urology Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200127 China.

Androgen deficiency is a physical disorder that not only affects adults but can also jeopardize children＇s health. Because there are many disadvantages to using traditional androgen replacement therapy, we have herein attempted to explore the use of human umbilical cord mesenchymal stem cells for the treatment of androgen deficiency. We transplanted CM-Dil-labeled human umbilical cord mesenchymal stem cells into the testes of an ethane dimethanesulfonate （EDS）-induced male rat hypogonadism model. Twenty-one days after transplantation, we found that blood testosterone levels in the therapy group were higher than that of the control group （P= 0.037）, and using immunohistochemistry and flow cytometry, we observed that some of the CM-Dil-labeled cells expressed Leydig cell markers for cytochrome P450, family 11, subfamily A, polypeptide 1, and 3-β-hydroxysteroid dehydrogenase. We then recovered these cells and observed that they were still able to proliferate in vitro. The present study shows that mesenchymal stem cells from human umbilical cord may constitute a promising therapeutic modality for the treatment of male hypogonadism patients.

关键词： Leydig cells stem cells testicular dysfunction

Serum HIF-1α and VEGF Levels Pre-and Post-TACE in Patients with Primary Liver Cancer

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Chinese Medical Sciences Journal 2011年第3期26卷 158-162页

作者： zhong-zhi Jia Guo-min Jiang Yao-liang Feng Department of Interventional Radiography Changzhou Second People＇s Hospital Affiliated to Nanjing Medical UniversityChangzhou 213003China Department of Interventional Radiography First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

Objective To investigate the expression levels of serum hypoxia inducible factor 1 alpha(HIF-1α) and vascular endothelial growth factor(VEGF) pre-and post-transcatheter arterial chemoembolization(TACE) in patients with primary liver cancer(PLC),and correlations between prognosis factors and serum HIF-1α as well as VEGF *** Forty consecutive patients fulfilling diagnostic criteria for PLC undergoing TACE from March 2008 to May 2009 were enrolled into the *** serum HIF-1α and VEGF levels of PLC patients pre-and 1 day,1 week,1 month post-TACE were analyzed using ELISA,and compared with that of 20 healthy *** were divided into complete response(CR) and partial response(PR),stable disease(SD),progressive disease(PD) groups according to the therapeutic *** correlation was used to analyze the correlation between different clinical variables and serum HIF-1α and VEGF levels before TACE,and correlation between serum HIF-1α and VEGF levels was also *** The expression levels of serum HIF-1α and VEGF in PLC patients were 154.94±83.29 and 264.00±148.10 pg/mL pre-TACE,and both of them were significantly higher than those in control group(23.84±8.15 and 69.78±21.42 pg/mL,all P<0.01).One day after TACE,both serum HIF-1α(570.64± 230.87 pg/mL) and VEGF levels(362.07±102.25 pg/mL) reached the peak values(all P<0.01).One week post-TACE,expression levels of them were decreased(198.62±92.11 and 283.52±145.46 pg/mL respectively),but still significantly higher than those before TACE(all P<0.01).The levels of both HIF-1α(133.96±57.02 vs.255.74±123.44 pg/mL) and VEGF(150.96±84.89 vs.368.95±161.90 pg/mL) in CR group 1 month post-TACE were significantly lower than those in PR+SD+PD group(all P<0.01).The level of serum HIF-1α was positively correlated with serum VEGF level(r=0.42,P<0.001).Both serum HIF-1α and VEGF levels were observed to be correlated with portal vein tumor thrombi(P<0.05) and metastasis(P<0.05).

关键词： liver neoplasms transcatheter arterial chemoembolization hypoxia induciblefactor 1 alpha vascular endothelial growth factor