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How mutual funds respond to asymmetric feedback tradingin China’s stock market

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Journal of Management science and Engineering 2024年第2期9卷 143-160页

作者： Die Wan Li yang Xiaoguang yang school of Finance Zhejiang Gongshang UniversityHangzhou310018China Business school University of New South WalesSydneyAustralia Academy of Mathematics and systems science Chinese Academy of SciencesBeijingChina

Previous studies show that individual investors play a dominant role in China's stock *** behavior of chasing-rise being stronger than killing-fall leads to asymmetry of feedback *** article investigates how mutual funds react to this market *** China's stock and fund data from 2003 to 2019,we find that mutual funds tend to hold fewer shares when asymmetric feedback trading of the relevant stock gets more *** negative relationship is robust after controlling past returns,turnover rates,and firm risk factors,moreover,it attenuates when the market sentiment is bullish or when stocks are allowed *** results show that mutual funds'selling towards asymmetric feedback trading does not make excess return but leads to significant risk *** findings may be related to uncertainty associated with asymmetric feedback trading,and thus support the limit market participation theory from the second largest stock market.

关键词： Asymmetric feedback trading Mutual fund shareholdings Uncertainty Market sentiment short selling

Distributional and behavioral responses of the wintering Oriental storks to drought in China’s largest freshwater lake

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Avian Research 2024年第2期15卷 187-195页

作者： Fucheng yang Mingqin shao Jianying Wang College of Life science Jiangxi Normal UniversityNanchang330022China

Extreme droughts are increasing in frequency and severity globally as a result of climate *** understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased *** numerous studies have investigated birds’responses to drought,the emphasis has primarily been on *** can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains *** this study,we surveyed the distri-bution and behavior of Oriental storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in *** indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental storks in the ***-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental *** time,Oriental storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller ***,the duration of Oriental storks’vigilance and moving be-haviors decreased significantly compared with that observed before the *** the drought,Oriental storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging *** accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental storks to increase their foraging *** a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental ***-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the pisc

关键词： Climate change Extreme drought Foraging behavior Oriental stork Poyang lake

Application of sparse s transform network with knowledge distillation in seismic attenuation delineation

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Petroleum science 2024年第4期21卷 2345-2355页

作者： Nai-Hao Liu Yu-Xin Zhang yang yang Rong-Chang Liu Jing-Huai Gao Nan Zhang school of Information and Communications Engineering Xi'an Jiaotong University school of software Engineering Xi'an Jiaotong University PetroChina Research Institute of Petroleum Exploration and Development (RIPED) CNPC Research Institute of Exploration and Development Yumen Oilfield Company CNPC

Time-frequency analysis is a successfully used tool for analyzing the local features of seismic ***, it suffers from several inevitable limitations, such as the restricted time-frequency resolution,the difficulty in selecting parameters, and the low computational efficiency. Inspired by deep learning,we suggest a deep learning-based workflow for seismic time-frequency analysis. The sparse s transform network(ssTNet) is first built to map the relationship between synthetic traces and sparse s transform spectra, which can be easily pre-trained by using synthetic traces and training labels. Next, we introduce knowledge distillation(KD) based transfer learning to re-train ssTNet by using a field data set without training labels, which is named the sparse s transform network with knowledge distillation(KD-ssTNet).In this way, we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training labels. To test the availability of the suggested KD-ssTNet, we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods.

关键词： s transform Deep learning Knowledge distillation Transfer learning seismic attenuation delineation

Energy Management of Price-maker Community Energy storage by stochastic Dynamic Programming

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CsEE Journal of Power and Energy systems 2024年第2期10卷 492-503页

作者： Lirong Deng Xuan Zhang Tianshu yang Hongbin sun yang Fu Qinglai Guo shmuel s.Oren Department of Electrical Engineering Shanghai University of Electric PowerShanghai 200000China Tsinghua-Berkeley shenzhen Institute Tsinghua UniversityShenzhen 518055China Department of Industrial Engineering and Operations Research University of California BerkeleyBerkeleyCAUSA Risk Analytics and Optimization Chair EPFLSwitzerlandand also with Power Systems LaboratoryETH Zurich8092 ZurichSwitzerland state Key Laboratory of Power systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

In this paper,we propose an analytical stochastic dynamic programming(sDP)algorithm to address the optimal management problem of price-maker community energy *** a price-maker,energy storage smooths price differences,thus decreasing energy arbitrage ***,this price-smoothing effect can result in significant external welfare changes by reduc-ing consumer costs and producer revenues,which is not negligible for the community with energy storage *** such,we formulate community storage management as an sDP that aims to maximize both energy arbitrage and community *** incorporate market interaction into the sDP format,we propose a framework that derives partial but sufficient market information to approximate impact of storage operations on market *** we present an analytical sDP algorithm that does not require state *** from computational efficiency,another advantage of the analytical algorithm is to guide energy storage to charge/discharge by directly comparing its current marginal value with expected future marginal *** studies indicate community-owned energy storage that maximizes both arbitrage and welfare value gains more benefits than storage that maximizes only *** proposed algorithm ensures optimality and largely reduces the computational complexity of the standard *** Terms-Analytical stochastic dynamic programming,energy management,energy storage,price-maker,social welfare.

关键词： Analytical stochastic dynamic programming energy management energy storage price-maker social welfare

用于无润滑加工、冷成形及其他工业应用的Mos2基镀层的性能

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用于无润滑加工、冷成形及其他工业应用的MoS2基镀层的性能

Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

第一届国际机械工程学术会议

作者： N.M Renevier s.yang W.southall V.CFox D.G Teer Teer Coatings Ltd. United.Kingdom

可以通过少量钛的复合沉积来改善Mos镀层的性能。这些MosTi复合镀层由闭合非平衡磁控溅镀产生的。它具有较高的硬度(1000～2000HV,Mos只有400HV),大得多的耐磨性(到100倍),并且在摩擦试验中对周边气氛水蒸汽有很少的敏感性(与Mos比较提... 详细信息

可以通过少量钛的复合沉积来改善Mos镀层的性能。这些MosTi复合镀层由闭合非平衡磁控溅镀产生的。它具有较高的硬度(1000～2000HV,Mos只有400HV),大得多的耐磨性(到100倍),并且在摩擦试验中对周边气氛水蒸汽有很少的敏感性(与Mos比较提高了2800倍)。它们能保持很低的特定磨损率4×10m/(m·N),0.02～0.1的低摩擦因数及高达5GPa的承载能力,这些镀层在广泛的切削,成形应用中获得了极好的工业成果。本文展示了当今应用在大规模的生产中的这些与MosT自动润滑镀层有关的性能数据。

关键词： Mos2 低摩擦坚硬耐磨层

来源： cnki会议评论

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Journal of systems Engineering and Electronics 2024年第2期35卷 495-508页

作者： yang Luyi LI Haiyang ZHANG Jin ZHU Yuehe College of Aerospace science and Engineering National University of Defense TechnologyChangsha 410073China China Astronauts Research and Training Center Beijing 100094China Hunan Key Laboratory of Intelligent Planning and simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency

On Leray's problem in an infinitely long pipe with the Navier-slip boundary condition

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science China Mathematics 2024年第4期67卷 819-854页

作者： Zijin Li Xinghong Pan Jiaqi yang school of Mathematics and statistics Nanjing University of Information Science and TechnologyNanjing 210044China school of Mathematics and Key Laboratory of Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China school of Mathematics and statistics Northwestern Polytechnical UniversityXi'an 710129China

The original Leray’s problem concerns the well-posedness of weak solutions to the steady incompressible Navier-stokes equations in a distorted pipe,which approach the Poiseuille flow subject to the no-slip boundary condition at spatial *** this paper,the same problem with the Navier-slip boundary condition instead of the no-slip boundary condition,is *** to the complexity of the boundary condition,some new ideas,presented as follows,are introduced to handle the extra difficulties caused by boundary ***,the Poiseuille flow in the semi-infinite straight pipe with the Navier-slip boundary condition will be introduced,which will serve as the asymptotic profile of the solution to the generalized Leray’s problem at spatial ***,a solenoidal vector function defined in the whole pipe,satisfying the Navierslip boundary condition,having the designated flux and equalling the Poiseuille flow at a large distance,will be carefully *** plays an important role in reformulating our ***,the energy estimates depend on a combined L2-estimate of the gradient and the stress tensor of the velocity.

关键词： stationary Navier-stokes system Navier-slip boundary condition Leray's problem

伴有大量视网膜下出血的原发性血小板减少性紫癜

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美国医学会眼科杂志（中文版） 2006年第4期18卷 242-243页

作者： Pulin A.shah sam s.yang Wayne E.Fung 李炳震（译）赵光喜（校）

原发性血小板减少性紫癜（ITP）是一种自身免疫性疾病，其抗体直接抗自身血小板引起末梢循环破环和脾性隔离症，从而导致血小板计数减少，偶尔还会有出血性并发症。ITP是一种相对少见的疾病，在一般人群中，它的发病率接近万分之一。普... 详细信息

原发性血小板减少性紫癜（ITP）是一种自身免疫性疾病，其抗体直接抗自身血小板引起末梢循环破环和脾性隔离症，从而导致血小板计数减少，偶尔还会有出血性并发症。ITP是一种相对少见的疾病，在一般人群中，它的发病率接近万分之一。普遍认为它是一种良性疾病，大部分患有ITP的成年患者在其它方面都很健康。

关键词：血小板减少性紫癜视网膜下出血原发性自身免疫性疾病出血性并发症自身血小板血小板计数 ITP

Conceptual design and configurations selection of s/H-UAVs based on Q-rung dual hesitant double layer FQFD

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Chinese Journal of Aeronautics 2024年第9期37卷 193-205页

作者： Dun yang Li LIU Wencan BAI Weiyong TIAN school of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

For the conceptual design phase of Unmanned Aerial Vehicles(UAVs),a process for conceptual design and configuration selection of solar/Hydrogen powered UAVs(s/H-UAVs)is *** design requirements of s/H-UAVs were analyzed *** proposed process used Fuzzy Quality Function Deployment(FQFD)to establish logical and quantitative ***,in order to appropriately describe the hesitancy of experts while making decision,it used Q-Rung Dual Hesitant Fuzzy sets(QRDHFs)to score the *** addition,a decision-making framework is proposed to perform a logical selection of typical layouts based on defuzzi-fication method and Technique for Order Preference by similarity to the Ideal solution(TOPsIs).The present process has been applied for s/*** resulting set of design requirements con-sists of three categories:Mission Requirements(MRs),Engineering Characteristics(ECs)and Tech-nical Indicators(TIs).Four typical layouts of s/H-UAVs were sorted and *** performance of four typical layouts were evaluated and the strut-Braced Wing(sBW)with external hydrogen storage was selected as the best layout for s/H-UAVs.

关键词： Hybrid powered UAV Conceptual design Q-Rung Dual Hesitant Fuzzy set(QRDHFs) Quality function deployment strut-braced wing