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The effect of affiliated analysts on stock recommendations: Evidence from share pledges in China 认领
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作者 Chenyu Zhang Aimin Qian Xiangyan Shi 《中国会计学刊:英文版》 2020年第1期79-107,共29页
We use the share pledge context in China to examine how affiliated analysts whose securities companies are pledgees of share pledge firms issue stock recommendations on these listed firms.We find that their recommenda... We use the share pledge context in China to examine how affiliated analysts whose securities companies are pledgees of share pledge firms issue stock recommendations on these listed firms.We find that their recommendations are more optimistic than those of non-affiliated analysts,and they are more likely to issue Buy and Add recommendations,suggesting that they issue optimistic rating reports for share pledge firms due to their conflicts of interest.We also find a dynamic adjustment in the stock recommendation behavior of these analysts,and their probability after issuing optimistic stock recommendations is significantly reduced before and after the years that the affiliation relationship between them and share pledge firms both began and ended.These affiliated analysts continue to issue optimistic stock recommendations after visiting the share pledge firms if they work in the same location as the firms,or if they are star analysts among New Fortune’s‘‘top five analysts,"and when the information transparency of the share pledge firms is higher.In addition,the optimistic stock recommendation behavior of affiliated analysts is more significant in our sample of firms with high share pledge ratios and downward stock price pressure.The earnings forecast quality of affiliated analysts is also found to be lower,and they are less inclined to downgrade stock recommendations for these share pledge firms.Buy recommendations issued by both nonaffiliated and affiliated analysts can bring cumulative excess returns in the short event window,but those issued by affiliated analysts are significantly negative in the long-term event window,and significantly lower than those issued by non-affiliated analysts.Overall,our study shows that affiliated analysts issue optimistic rating reports on share pledge firms due to conflicts of interest,which leads to decision-making bias in investors and thus decreases the stock price crash risk of the firms.Our findings further reveal the economic consequences of share pledging and extend o 展开更多
关键词 Affiliated ANALYSTS Stock recommendations SHARE PLEDGE Information SUPERIORITY INTEREST CONFLICT
Precision Matrix Estimation by Inverse Principal Orthogonal Decomposition 认领
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作者 Cheng Yong Tang Yingying Fan Yinfei Kong 《数学研究通讯:英文版》 CSCD 2020年第1期68-92,共25页
We investigate the structure of a large precision matrix in Gaussian graphical models by decomposing it into a low rank component and a remainder part with sparse precision matrix.Based on the decomposition,we propose... We investigate the structure of a large precision matrix in Gaussian graphical models by decomposing it into a low rank component and a remainder part with sparse precision matrix.Based on the decomposition,we propose to estimate the large precision matrix by inverting a principal orthogonal decomposition(IPOD).The IPOD approach has appealing practical interpretations in conditional graphical models given the low rank component,and it connects to Gaussian graphical models with latent variables.Specifically,we show that the low rank component in the decomposition of the large precision matrix can be viewed as the contribution from the latent variables in a Gaussian graphical model.Compared with existing approaches for latent variable graphical models,the IPOD is conveniently feasible in practice where only inverting a low-dimensional matrix is required.To identify the number of latent variables,which is an objective of its own interest,we investigate and justify an approach by examining the ratios of adjacent eigenvalues of the sample covariance matrix・Theoretical properties,numerical examples,and a real data application demonstrate the merits of the IPOD approach in its convenience,performance,and interpretability. 展开更多
关键词 High-dimensional data analysis latent Gaussian graphical model precision matrix
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Artificial intelligence in pediatrics 认领
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作者 Ya-Wen Li Fang Liu +3 位作者 Tian-Nan Zhang Fang Xu Yu-Chen Gao Tian Wu 《中华医学杂志:英文版》 SCIE CAS CSCD 2020年第3期358-360,共3页
The rapid development of information technology has involved advances in artificial intelligence(AI),big data processing,and cloud computing,with significant and farreaching effects on the structure and efficiency of ... The rapid development of information technology has involved advances in artificial intelligence(AI),big data processing,and cloud computing,with significant and farreaching effects on the structure and efficiency of the traditional healthcare industry,as well as the establishment and maintenance of modern medical management information systems.AI solutions for handling data in the medical field,such as electronic medical records,medical imaging technology,medical big data,intelligent drug design,and smart health management systems have emerged,which improve the standardization and accuracy of clinical decision making,while providing more dimensions of data accumulation for medical knowledge-based systems.These developments can also support physicians and researchers in the optimization of treatment plans,and decision making about optimal treatment options.This review aims to summarize recent advances in the research and clinical use of AI in pediatrics. 展开更多
关键词 DIMENSIONS INTELLIGENCE ADVANCES
Polarization and fundamental sensitivity of 39K(133Cs)-85Rb-21Ne co-magnetometers 认领
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作者 刘建华 靖东洋 +3 位作者 庄琳 全伟 房建成 刘伍明 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第4期272-283,共12页
The hybrid optical pumping spin exchange relaxation free(HOPSERF)atomic co-magnetometers make ultrahigh sensitivity measurement of inertia achievable.The wall relaxation rate has a big effect on the polarization and f... The hybrid optical pumping spin exchange relaxation free(HOPSERF)atomic co-magnetometers make ultrahigh sensitivity measurement of inertia achievable.The wall relaxation rate has a big effect on the polarization and fundamental sensitivity for the co-magnetometer,but it is often neglected in the experiments.However,there is almost no work about the systematic analysis of the influence factors on the polarization and the fundamental sensitivity of the HOPSERF co-magnetometers.Here we systematically study the polarization and the fundamental sensitivity of 39K-85Rb-21Ne and 133Cs-85Rb-21Ne HOPSERF co-magnetometers with low polarization limit and the wall relaxation rate.The 21Ne number density,the power density and wavelength of pump beam will affect the polarization greatly by affecting the pumping rate of the pump beam.We obtain a general formula on the fundamental sensitivity of the HOPSERF co-magnetometers due to shot-noise and the fundamental sensitivity changes with multiple systemic parameters,where the suitable number density of buffer gas and quench gas make the fundamental sensitivity highest.The fundamental sensitivity 7.5355×10^-11 rad·s^-1·Hz^-1/2 of 133Cs-85Rb-21Ne co-magnetometer is higher than the ultimate theoretical sensitivity 2×10^-10 rad·s^-1·Hz^-1/2 of K-21Ne co-magnetometer. 展开更多
关键词 hybrid optical pumping spin exchange relaxation free co-magnetometer wall relaxation rate
Simultaneous Estimation of Multiple Conditional Regression Quantiles 认领
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作者 Yan-ke WU Ya-nan HU +1 位作者 Jian ZHOU Mao-zai TIAN 《应用数学学报:英文版》 SCIE CSCD 2020年第2期448-457,共10页
In this article, we put forward a new approach to estimate multiple conditional regression quantiles simultaneously. Unlike the double summation method in most of the literatures, our proposed model allows continuous ... In this article, we put forward a new approach to estimate multiple conditional regression quantiles simultaneously. Unlike the double summation method in most of the literatures, our proposed model allows continuous variety for the quantile level over(0,1). As a result, all the quantile curves can be obtained via a 2-dimensional surface simultaneously. Most importantly, the proposed minimizing criterion can be readily transformed to a linear programming problem. We use tensor product bi-linear quantile smoothing B-splines tofit it. The asymptotic property of the estimator is derived and a real data set is analyzed to demonstrate the proposed method. 展开更多
关键词 Simultaneous Estimation Conditional Regression Quantiles B-SPLINE Tensor Product
Monetary Policy and Borrowers'Loan Defaults:Research Based on Data from Ren re ndai 认领
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作者 Wenda Song Haiyang Zhang 《中国与世界经济:英文版》 SCIE 2020年第1期94-121,共28页
This paper uses Renrendai data to study the relationship between monetaryj policy and the default behavior of borrowers,and analyzes the transmission channels.The research shows that tight monetary policy will lead to... This paper uses Renrendai data to study the relationship between monetaryj policy and the default behavior of borrowers,and analyzes the transmission channels.The research shows that tight monetary policy will lead to a significant increase in a borrower s probability to default,and this effect will continue for several months.There may be two transmission channels:(i)monetary policy changes a debtor s liquidity through credit and balance sheet channels,which directly affects their current repayment behavior;and(ii)monetary policy may affect a borrower s investment,production and profitability,thus changing their long-term solvency.The paper also finds that the repayment behavior of productive borrowers is more susceptible to monetary policy than consumptive borrowers,and that the default behavior of borrowers in coastal provinces is more susceptible to monetary policy than of borrowers in inland provinces.These findings provide new evidence for understanding how monetary policy affects individual behavior and its transmission mechanisms. 展开更多
关键词 DEFAULT LIQUIDITY monetary policy online LENDING
You Are How You Behave-Spatiotemporal Representation Learning for College Student Academic Achievement 认领
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作者 Xiao-Lin Li Li Ma +1 位作者 Xiang-Dong He Hui Xiong 《计算机科学技术学报:英文版》 SCIE EI CSCD 2020年第2期353-367,共15页
Scholarships are a reflection of academic achievement for college students.The traditional scholarship assignment is strictly based on final grades and cannot recognize students whose performance trend improves or dec... Scholarships are a reflection of academic achievement for college students.The traditional scholarship assignment is strictly based on final grades and cannot recognize students whose performance trend improves or declines during the semester.This paper develops the Trajectory Mining on Clustering for Scholarship Assignment and Academic Warning(TMS)approach to identify the factors that affect the academic achievement of college students and to provide decision support to help low-performing students attain better performance.Specifically,we first conduct feature engineering to generate a set of features to characterize the lifestyles patterns,learning patterns,and Internet usage patterns of students.We then apply the objective and subjective combined weighted k-means(Wosk-means)algorithm to perform clustering analysis to identify the characteristics of different student groups.Considering the difficulty in obtaining the real global positioning system(GPS)records of students,we apply manually generated spatiotemporal trajectories data to quantify the direction of trajectory deviation with the assistance of the PrefixSpan algorithm to identify low-performing students.The experimental results show that the silhouette coefficient and Calinski-Harabasz index of the Wosk-means algorithm are both approximately 1.5 times to that of the best baseline algorithm,and the sum of the squared error of the Wosk-means algorithm is only the half of the best baseline algorithm. 展开更多
关键词 academic achievement spatiotemporal trajectory feature engineering student segmentation
A hybrid optimization approach for the heterogeneous vehicle routing problem with multiple depots cooperative operation 认领
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作者 刘建胜 Tan Wenyue +1 位作者 Jiang Hai Yu Gong 《高技术通讯:英文版》 EI CAS 2020年第1期108-117,共10页
With the challenge of great growing of transport diversity for the automobile enterprises, the heterogeneous vehicle routing problem with multiple depots, multiple types of finished vehicles and multiple types of tran... With the challenge of great growing of transport diversity for the automobile enterprises, the heterogeneous vehicle routing problem with multiple depots, multiple types of finished vehicles and multiple types of transport vehicles in finished vehicle logistics(HVRPMD) is modelled and solved. A multi-objective optimization model for HVRPMD is presented considering loading constraints to minimize the total cost and minimize the number of transport vehicles. Then a hybrid heuristic algorithm based on genetic algorithm and particle swarm optimization(GA-PSO) is developed. Moreover, a case study is used to evaluate the effectiveness of this algorithm. By comparing the GA-PSO algorithm with the traditional GA algorithm, the simulation results demonstrate the proposed GA-PSO algorithm is able to better support the HVRPMD problem in practice. Contributions of the paper are the modelling and solving of a complex HVRPMD in logistics industry. 展开更多
关键词 finished VEHICLE logistics(FVL) VEHICLE ROUTING problem(VRP) hybrid HEURISTIC algorithm multiple factory DEPOT
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二维Ⅲ族硫化物Janus多层结构的高效光解水特性:内建电场和空位缺陷效应 认领
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作者 范英才 马西奎 +4 位作者 王君茹 宋晓涵 王爱珠 刘宏 赵明文 《科学通报:英文版》 SCIE EI CSCD 2020年第1期27-34,M0003共9页
二维范德华材料被广泛用作光分解水催化剂,但其直接的能量转化效率有待提高.因此,寻找具有高效光解水催化特性的二维材料成为理论和实验研究的热点.本文从量子力学第一性原理出发,预言了一类具有高效光解水特性的光催化剂:二维Ⅲ族硫化... 二维范德华材料被广泛用作光分解水催化剂,但其直接的能量转化效率有待提高.因此,寻找具有高效光解水催化特性的二维材料成为理论和实验研究的热点.本文从量子力学第一性原理出发,预言了一类具有高效光解水特性的光催化剂:二维Ⅲ族硫化物Janus多层结构InGaXY,M2XY和InGaX2(M=In/Ga;X,Y=S/Se/Te).理论计算表明,多层材料的内建电场不仅可以促进光生载流子的空间分离,而且可以有效地调控材料能带的位置,提高能量转化效率.Janus多层材料能量转化效率的理论上限可以达到38.5%,接近了理论极限值(47%).更重要的是,在InGaSSe双层引入Ga空位可以有效降低析氢和析氧反应的过电势,仅仅依靠光生载流子提供的电压就可以驱动光解水催化反应.该理论结果不仅预言了二维Ⅲ族硫化物Janus多层材料可以作为高效的光解水催化材料,而且为设计和寻找高效光催化材料提供了新思路. 展开更多
关键词 JANUS group-Ⅲchalcogenides Solar-to-hydrogen efficiency Photocatalytic water splitting Intrinsic electric fields FIRST-PRINCIPLE calculation
一种通过取向聚合物网络提高驱动性能的各向异性纳米复合水凝胶 认领
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作者 唐萍 严昊 +5 位作者 陈列 吴青山 赵天艺 李书宏 高海南 刘明杰 《中国科学:材料科学(英文版)》 SCIE EI CSCD 2020年第5期832-841,共10页
各向异性复合水凝胶在驱动器和传感器材料领域具有广泛的应用.本研究报道了一种通过机械应变诱导方法制备的各向异性复合水凝胶.包含聚(N-异丙基丙烯酰胺)(PNIPAM)和海藻酸钠(SA)的聚合物网络和碳纳米管(CNTs)被拉伸同时取向,然后由非... 各向异性复合水凝胶在驱动器和传感器材料领域具有广泛的应用.本研究报道了一种通过机械应变诱导方法制备的各向异性复合水凝胶.包含聚(N-异丙基丙烯酰胺)(PNIPAM)和海藻酸钠(SA)的聚合物网络和碳纳米管(CNTs)被拉伸同时取向,然后由非共价键物理交联固定这种取向结构.具有双重取向聚合物网络的复合水凝胶显示出各向异性的光学和机械性能.与各向同性复合水凝胶相比,各向异性复合水凝胶的驱动性能得到了提高,它能够以20%的收缩形变提起自身重量100倍的重物.此外,制备的双层水凝胶最大可弯曲390°,并且能够模仿植物的卷须缠绕支撑物. 展开更多
关键词 ANISOTROPIC PNIPAM-based hydrogels interpenetrating polymer network ACTUATION
MABAC method for multiple attribute group decision making under q-rung orthopair fuzzy environment 认领
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作者 Jie Wang Guiwu Wei +1 位作者 Cun Wei Yu Wei 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第1期208-216,共9页
As the generalization of intuitionistic fuzzy set(IFS) and Pythagorean fuzzy set(PFS),the q-rung orthopair fuzzy set(q-ROFS) has emerged as a more meaningful and effective tool to solve multiple attribute group decisi... As the generalization of intuitionistic fuzzy set(IFS) and Pythagorean fuzzy set(PFS),the q-rung orthopair fuzzy set(q-ROFS) has emerged as a more meaningful and effective tool to solve multiple attribute group decision making(MAGDM) problems in management and scientific domains.The MABAC(multi-attributive border approximation area comparison) model,which handles the complex and uncertain decision making issues by computing the distance between each alternative and the bored approximation area(BAA),has been investigated by an increasing number of researchers more recent years.In our article,consider the conventional MABAC model and some fundamental theories of q-rung orthopair fuzzy set(q-ROFS),we shall introduce the q-rung orthopair fuzzy MABAC model to solve MADM problems.at first,we briefly review some basic theories related to q-ROFS and conventional MABAC model.Furthermore,the q-rung orthopair fuzzy MABAC model is built and the decision making steps are described.In the end,An actual MADM application has been given to testify this new model and some comparisons between this novel MABAC modeL and two q-ROFNs aggregation operators are provided to further demonstrate the merits of the q-rung orthopair fuzzy MABAC model. 展开更多
关键词 MAGDM problems Q-rung orthopair FUZZY sets(q-ROFSs) MABAC MODEL Q-rung orthopair FUZZY WEIGHTED average(q-ROFWA)operators Q-rung orthopair FUZZY WEIGHTED geometric(q-ROFWG)operators Q-ROFNs MABAC MODEL Construction project
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Ba3LaNa(PO4)3F:Tm^3+,Dy^3+:A tunable blue-white color emitting phosphor via energy transfer for UV white LEDs 认领
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作者 Dingdian Xu Wei Zhou +1 位作者 Shujing Li Dongsheng Bai 《中国化学快报:英文版》 SCIE CAS CSCD 2020年第2期575-578,共4页
A series of Tm^3+/Dy^3+co-doped Ba3 LaNa(PO4)3 F(BLNPF) phosphors were synthesized successfully via a high-temperature solid-reaction,and luminescence properties were investigated.Upon near violet excitation,BLNPF:Tm^... A series of Tm^3+/Dy^3+co-doped Ba3 LaNa(PO4)3 F(BLNPF) phosphors were synthesized successfully via a high-temperature solid-reaction,and luminescence properties were investigated.Upon near violet excitation,BLNPF:Tm^3+,Dy^3+ phosphors exhibit Tm^3+:^1D2-^3 F4 and Dy^3+:^4 F(9/2)-^6 HJ(J=15/2,13/2,11/2)transitions with diffe rent luminescence intensity.The emitting color of the obtained products was found to shift from blue to white as a result of efficient energy transfer(ET) from Tm^3+to Dy^3+ions.According to photoluminescence emission intensity,the positive effect of activator on ET efficiency was calculated and the maximum ET efficiency was found around 72.6% with Dy^3+ concentration was 0.04.By means of Dexter's theoretical model,furthermore,dipole-dipole interaction was confirmed as the mechanism of energy transfer from Tm^3+ to Dy^3+ ions.The results suggested that BLNPF:Tm^3+,Dy^3+ phosphor might be a promising single-phased white-light-emitting phosphor for UV white-light LED. 展开更多
关键词 PHOSPHORS Ba3LaNa(PO4)3F Luminescence Energy transfer White light
Novel methylation gene panel in adjacent normal tissues predicts poor prognosis of colorectal cancer in Taiwan 认领
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作者 Chih-Hsiung Hsu Cheng-Wen Hsiao +8 位作者 Chien-An Sun Wen-Chih Wu Tsan Yang Je-Ming Hu Chi-Hua Huang Yu-Chan Liao Chao-Yang Chen Fu-Huang Lin Yu-Ching Chou 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第2期154-167,共14页
BACKGROUND It is evident that current clinical criteria are suboptimal to accurately estimate patient prognosis.Studies have identified epigenetic aberrant changes as novel prognostic factors for colorectal cancer(CRC... BACKGROUND It is evident that current clinical criteria are suboptimal to accurately estimate patient prognosis.Studies have identified epigenetic aberrant changes as novel prognostic factors for colorectal cancer(CRC).AIM To estimate whether a methylation gene panel in different clinical stages can reflect a different prognosis.METHODS We enrolled 120 CRC patients from Tri-Service General Hospital in Taiwan and used the candidate gene approach to select six genes involved in carcinogenesis pathways.Patients were divided into two groups based on the methylation status of the six evaluated genes,namely,the<3 aberrancy group and≥3 aberrancy group.Various tumor stages were divided into two subgroups(local and advanced stages)on the basis of the pathological type of the following tissues:Tumor and adjacent normal tissues(matched normal).We assessed DNA methylation in tumors and adjacent normal tissues from CRC patients and analyzed the association between DNA methylation with different cancer stages and the prognostic outcome including time to progression(TTP)and overall survival.RESULTS We observed a significantly increasing trend of hazard ratio as the number of hypermethylated genes increased both in normal tissue and tumor tissue.The 5-year TTP survival curves showed a significant difference between the≥3 aberrancy group and the<3 aberrancy group.Compared with the<3 aberrancy group,a significantly shorter TTP was observed in the≥3 aberrancy group.We further analyzed the interaction between CRC prognosis and different cancer stages(local and advanced)according to the methylation status of the selected genes in both types of tissues.There was a significantly shorter 5-year TTP for tumors at advanced stages with the promoter methylation status of selected genes than for those with local stages.We found an interaction between cancer stages and the promoter methylation status of selected genes in both types of tissues.CONCLUSION Our data provide a significant association between the methylation markers in normal 展开更多
关键词 DNA METHYLATION PANEL genes Clinical stage Prognosis outcome ADJACENT normal TISSUES COLORECTAL cancer
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共享经济对旅游经济人本因素的影响及信息技术的作用 认领
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作者 Marianna SIGALA 丁于思(译) 向征(校) 《旅游学刊》 CSSCI 北大核心 2020年第1期5-7,共3页
共享经济的规模和范围的快速增长影响了旅游体验的方方面面。当今任何人都可以通过交换、分享、商业化和货币化其拥有的、但未充分利用的资源,成为一名旅游业微型企业家,在全球市场上出售其专业服务。事实上,共享经济已经成为存在于从... 共享经济的规模和范围的快速增长影响了旅游体验的方方面面。当今任何人都可以通过交换、分享、商业化和货币化其拥有的、但未充分利用的资源,成为一名旅游业微型企业家,在全球市场上出售其专业服务。事实上,共享经济已经成为存在于从美国、欧洲到中国、印度和澳大利亚的众多国家和文化中的全球化的现实。它是超级消费社会和竞争激烈的市场经济的替代解决方案,因为它号称支持可持续发展,促进人与人之间的社会联系、理解和团结,为那些无法进入传统全职劳动力市场的人提供就业机会。 展开更多
关键词 共享经济平台 饮食习惯 企业家 微型企业 零工经济 旅游业 重新定义 信息技术
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Grey information coverage interaction relational decision making and its application 认领
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作者 XIAO Qinzi SHAN Miyuan +1 位作者 GAO Mingyun XIAO Xinping 《系统工程与电子技术:英文版》 SCIE EI CSCD 2020年第2期359-369,共11页
This study aims to reflect the information coverage grey number and the interaction between attributes in grey relational decision making. Therefore, a multi-attribute decision method based on the grey information cov... This study aims to reflect the information coverage grey number and the interaction between attributes in grey relational decision making. Therefore, a multi-attribute decision method based on the grey information coverage interaction relational degree(GIRD) is proposed. Firstly, this paper defines the information coverage grey number, and establishes the GIRD model by using the Choquet fuzzy integral and grey relational principle. It proves that the proposed model not only is the general and unified form of the point relational degree, interval relational degree, mixed relational degree and grey fuzzy integral relational degree, but also can effectively deal with the interaction between attributes. Further,a decision making example of evaluating the industrial operation quality for 14 cities in Hunan province of China is provided to highlight the implementation, availability, and feasibility of the proposed decision model. 展开更多
关键词 grey information coverage interaction effect fuzzy integral grey relational degree industrial quality evaluation
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Rare Earth Permanent Magnets and Their Place in the Future Economy 认领
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作者 Allan Trench John P.Sykes 《工程(英文)》 SCIE EI 2020年第2期115-118,共4页
Due to their rising economic importance as an enabling technology for the energy transition from fossil fuels to renewables[1-3]and to their ubiquitous use in the miniaturization of electronic devices[2,4],permanent m... Due to their rising economic importance as an enabling technology for the energy transition from fossil fuels to renewables[1-3]and to their ubiquitous use in the miniaturization of electronic devices[2,4],permanent magnets are one of the key frontiers of technological development in the modern world. 展开更多
关键词 EARTH FRONTIER RARE
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Making Sense of Reconstruction Models for Human Intention Detection 认领
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作者 Wei Liang Dalin Zhang +1 位作者 Xigang Yuan Kaixuan Chen 《中国通信:英文版》 SCIE CSCD 2020年第4期180-192,共13页
Movement intention recognition paves the path to developing Brain-Computer Interface(BCI)applications.Current research mostly focuses on questions like“which hand is intended to move”.While answering questions like... Movement intention recognition paves the path to developing Brain-Computer Interface(BCI)applications.Current research mostly focuses on questions like“which hand is intended to move”.While answering questions like“whether a hand is intended to move”is more desirable for widely real-world applications,because we cannot continuously perform intention tasks during usage,and the gap periods may cause unintended operation resulting in system failures.However,this kind of intention detection task is more difficult,since for a“whether”problem,it is hard to know what the“not”situation is and consequently to acquire training samples for the“not”situation.Furthermore,the occurrence of genuine intentions is comparatively scarce and unexpected,making the intention detection task hard and computation-consuming.To tackle this problem,we propose a Reconstruction-based Intention Detection(RID)framework,which utilises a reconstruction model to represent a high-level abstraction of EEG signals and leverages the reconstruction errors to determine“whether”there is a movement intention.Our framework is not only theoretically flexible and robust to any sophisticated real-world scenarios but also hand-crafted feature and domain knowledge free.Comprehensive experiments on detecting movement intention tasks with different reconstruction models demonstrate the promising performance of the proposed reconstruction intention detection framework. 展开更多
关键词 INTENTION consuming RECONSTRUCTION
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Kernel semi-supervised graph embedding model for multimodal and mixmodal data 认领
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作者 Qi ZHANG Rui LI Tianguang CHU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2020年第1期243-245,共3页
Dear editor,Semi-supervised learning has obtained increasing interests in machine learning,because making use of both labeled and unlabeled training samples helps extracting discriminative features and meanwhile reduc... Dear editor,Semi-supervised learning has obtained increasing interests in machine learning,because making use of both labeled and unlabeled training samples helps extracting discriminative features and meanwhile reduces the time-consuming and labor-intensive labeling burden.For extracting features upon multimodal(i.e.,data of the same class exhibits separate clustering)and mixmodal(i.e.,data from different classes has mixed modality)data[1],we have presented a semi-supervised graph embedding(SGE)model in[2]to incorporate the soft label information with hierarchical locality of data.Through the maximizing process upon the weighted between-class separability as well as the minimizing processes upon the localitypreserved within-class and scaled overall-class data distances respectively,the intrinsic characters of data with multimodal or mixmodal distributing properties can be well captured. 展开更多
关键词 MODAL EMBEDDING EXTRACTING
Study on the Present Situation and Influencing Factors of Farmers'Agricultural Insurance Demand in Poverty-Stricken Mountainous Areas 认领
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作者 Liu YANG Liwen XIANG Jing ZENG 《亚洲农业研究:英文版》 2020年第4期24-27,共4页
Agricultural insurance can avoid the risks of agricultural production and operation to a large extent,promote agricultural development and increase farmers'income,and lay a solid foundation for rural revitalizatio... Agricultural insurance can avoid the risks of agricultural production and operation to a large extent,promote agricultural development and increase farmers'income,and lay a solid foundation for rural revitalization.At present,China's agricultural insurance is in the stage of all-round development,and there are still many problems,especially the farmers'mistrust of agricultural insurance and their weak willingness to participate in agricultural insurance.Based on the data and information obtained from the field visit and questionnaire survey in Enshi Prefecture,this paper makes an empirical analysis on the factors affecting farmers'agricultural insurance demand by using binary Logistic regression model.According to the conclusion of the analysis,this paper puts forward the corresponding measures and suggestions from the three dimensions of the government,insurance companies and farmers. 展开更多
关键词 AGRICULTURAL INSURANCE DEMAND WILLINGNESS Data analysis Influencing factors
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The Evolution Dynamic and Long-Run Equilibrium in a Stock Market with Heterogeneous Traders 认领
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作者 Pengju Zhao Wei Zhang Yumin Liu 《Journal of Systems Science and Systems Engineering(系统科学与系统工程学报:英文版)》 SCIE EI CSCD 2020年第1期55-67,共13页
This paper uses ideas from biological evolution to analyze the evolution of the securities market in which rational and irrational traders coexist.A market evolutionary model is developed to describe the dynamic traje... This paper uses ideas from biological evolution to analyze the evolution of the securities market in which rational and irrational traders coexist.A market evolutionary model is developed to describe the dynamic trajectories of rational and irrational traders'wealth.The main question is,are irrational traders eliminated as the securities market evolves.The paper considers the impact of new entrants on the security market long-term equilibrium.In addition,it discusses the existence and uniqueness of the long-term equilibrium The paper finds that,under some market conditions,irrational traders could survive in the long run. 展开更多
关键词 Behavioral Finance IRRATIONAL TRADERS financial EVOLUTION theory random DYNAMIC system
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