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投资者非理性与中国股票异象——基于异质信念的视角

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管理科学学报 2024年第4期27卷 142-158页

作者：李林波刘维奇贺亚楠翟晓英山西财经大学会计学院太原030006 山西大学管理与决策研究所太原030031

投资者非理性是影响资产价格形成的一个重要因素,为检验投资者非理性特征对股票异象的影响,本研究利用1997年—2020年的股票交易数据,基于异质信念指标的构建思路构建了一个非理性信念指标,并实证探究了该指标对股票异象的影响.结果发现... 详细信息

投资者非理性是影响资产价格形成的一个重要因素,为检验投资者非理性特征对股票异象的影响,本研究利用1997年—2020年的股票交易数据,基于异质信念指标的构建思路构建了一个非理性信念指标,并实证探究了该指标对股票异象的影响.结果发现,非理性信念对未来收益具有负向预测能力;为了检验该指标对异象收益的解释能力,本文构建了一个包含市场因子(MKT)、规模因子(SMB)和信念因子(FMG)的信念因子模型,并复制了市场摩擦类、动量反转类、价值成长类、投资类、盈利类和无形资产类等102个股票异象,使用CAPM模型、FF-5模型、CH-3模型和信念因子模型对比发现,无论是调整的alpha值显著性还是GRS检验结果,信念因子模型都具有相对优势,说明非理性信念可能是导致股票异象形成的主要因子.

关键词：非理性信念股票异象因子定价模型异质信念

Shear behaviour of anchored jointed rock mass under different engineering conditions considering damage and joint surface morphology

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Underground Space 2023年第6期13卷 316-334页

作者： Zenghui Zhao wei Sun Shaojie Chen hao Liu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China Department of Petroleum Engineering China University of Petroleum-BeijingBeijing 102249China

According to different geological conditions and engineering disturbance,three dimensional numerical models of anchored jointed rock mass with two kinds of boundary conditions of constant normal load(CNL)and constant normal stiffness(CNS)were constructed considering the ductility damage of rockbolt,the stiffness degradation of grouting layer and the joint surface *** effects of anchorage angle,joint surface morphology,and boundary conditions on the shear performance of anchorage system were analyzed,and the failure characteristics under different working conditions were ***,the analytical solution of shear strength of anchored system was *** show that the larger the anchorage angle is,the more serious the necking phenomenon of rockbolt will *** damage degree of the bonding layer and the horizontal displacement of the bedding rock mass decrease with the increase of the joint surface *** CNL condition is to instantaneously apply high normal stress,and the CNS condition is to gradually form a high normal stress environment through the superposition of increment on the basis of the initial value,which can resist greater transverse *** is equivalent to enhancing the ductility of the *** shear strength of the system increases with the increase of normal stress and normal *** the normal stiffness will underestimate the shear strength.

关键词： Anchored jointed rock mass Normal stress Normal stiffness Progressive damage

32份早熟禾种质资源表型性状遗传多样性分析

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草业科学 2024年第6期41卷 1324-1335页

作者：金玲宋美琪鲍根生刘勇徐航何霖魏小星青海大学畜牧兽医科学院/青海省青藏高原优良牧草种质资源利用重点实验室青海西宁810016

本研究以32份早熟禾(Poa)种质资源为研究对象,利用多样性分析、相关性分析、主成分分析和聚类分析,评价其表型性状的变异水平,为青藏高原高寒地区早熟禾种质资源的品种选育提供依据。结果表明:通过多样性分析,遗传多样性指数最高的是总... 详细信息

本研究以32份早熟禾(Poa)种质资源为研究对象,利用多样性分析、相关性分析、主成分分析和聚类分析,评价其表型性状的变异水平,为青藏高原高寒地区早熟禾种质资源的品种选育提供依据。结果表明:通过多样性分析,遗传多样性指数最高的是总生物量(H′=2.21),变异系数最大的是株高(31.70%),其次是根长(22.04%)、总生物量(19.21%)和茎粗(16.38%);通过主成分分析得出第1主成分贡献率最大(30.274%),载荷量由高到低分别是花序长(0.748)、叶面积(0.746)、叶宽(0.705)、茎粗(0.704);通过聚类分析和综合得分,将资源分为Ⅲ大类,第Ⅰ类具有植株高大、茎叶比大、花序多,茎秆粗壮等特点,筛选出18-182、18-004、17-060这3份材料适合在饲草生产、混播草地等方面应用;第Ⅱ类具有植株矮小、叶片短而宽等特点,筛选出14-061这1份材料适合在生态恢复方面加以利用;第Ⅲ类具有植株矮小、叶片长而窄、生物量大等特点,筛选出17-105、17-332、18-064、18-139、15-048、17-044这6份材料可作为观赏利用型目标亲本进行品种培育。

关键词：早熟禾种质资源遗传多样性表型性状筛选优质种质表型变异性表型多样性

J-shaped association between dietary thiamine intake and the risk of cognitive decline in cognitively healthy,older Chinese individuals

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General Psychiatry 2024年第1期37卷 44-52页

作者： Chengzhang Liu Qiguo Meng Yuanxiu wei Xinyue Su Yuanyuan Zhang Panpan He Chun Zhou Mengyi Liu Ziliang Ye Xianhui Qin Department of Epidemiology and Biostatistics School of Public HealthAnhui Medical UniversityHefeiAnhuiChina institute of Biomedicine Anhui Medical UniversityHefeiAnhuiChina Division of Nephrology Nanfang HospitalSouthern Medical UniversityNational Clinical Research Center for Kidney DiseaseState Key Laboratory of Organ Failure ResearchGuangdong Provincial Institute of NephrologyGuangdong Provincial Key Laboratory of Renal Failure ResearchGuangzhou Regenerative Medicine and Health Guangdong LaboratoryGuangzhouGuangdongChina

Background The prospective association of dietary thiamine intake with the risk of cognitive decline among the general older adults remains *** To investigate the association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese *** The study included a total of 3106 participants capable of completing repeated cognitive function *** nutrient intake information was collected through 3-day dietary recalls and using a 3-day food-weighed method to assess cooking oil and condiment *** decline was defined as the 5-year decline rate in global or composite cognitive scores based on a subset of items from the Telephone Interview for Cognitive *** The median follow-up duration was 5.9 *** was a J-shaped relationship between dietary thiamine intake and the 5-year decline rate in global and composite cognitive scores,with an inflection point of 0.68 mg/day(95%confidence interval(Cl):0.56 to 0.80)and a minimal risk at 0.60-1.00 mg/day of dietary thiamine *** the inflection point,thiamine intake was not significantly associated with cognitive *** the inflection point,each unit increase in thiamine intake(mg/day)was associated with a significant decrease of 4.24(95%Cl:2.22 to 6.27)points in the global score and 0.49(95%Cl:0.23 to 0.76)standard units in the composite score within 5 years.A stronger positive association between thiamine intake and cognitive decline was observed in those with hypertension,obesity and those who were non-smokers(all pline in cognitively healthy,older Chinese individuals,with an inflection point at 0.68 mg/day and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake.

关键词： intake shaped cognitive

8个紫花苜蓿品种在柴达木旱区的生产性能综合评价

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干旱地区农业研究 2024年第2期42卷 33-40页

作者：徐航何霖宋美琪金玲鲍根生刘勇魏小星青海大学畜牧兽医科学院青海省青藏高原优良牧草种质资源利用重点实验室青海西宁810016

为筛选出适宜青海省柴达木旱区种植的紫花苜蓿品种,于2020—2022年对引进的8个紫花苜蓿品种进行生产性能评比试验,并采用隶属函数法综合评价适合柴达木旱区种植的优质紫花苜蓿品种。两年试验结果表明:(1)在2021年,东苜2号的干草产量最高... 详细信息

为筛选出适宜青海省柴达木旱区种植的紫花苜蓿品种,于2020—2022年对引进的8个紫花苜蓿品种进行生产性能评比试验,并采用隶属函数法综合评价适合柴达木旱区种植的优质紫花苜蓿品种。两年试验结果表明:(1)在2021年,东苜2号的干草产量最高,为11373.44 kg·hm^(-2);在2022年,龙牧803的干草产量最高,为13485.54 kg·hm^(-2);(2)5909在两年的粗蛋白含量和相对饲喂价值均最高,分别为14.71%和126.01、14.07%和128.01,而酸性洗涤纤维含量均最低,分别为38.67%和36.90%;东苜2号两年的中性洗涤纤维含量均最低,分别为53.68%和51.35%;(3)基于隶属函数法对各紫花苜蓿品种生产性能的综合评价,东苜2号、龙牧803和5909综合性状表现较好,在柴达木干旱区适应性强、饲草产量及品质最优,建议在本地优先推广种植。

关键词：紫花苜蓿生产性能隶属函数综合评价柴达木旱区

Deep-learning-based cryptanalysis of two types of nonlinear optical cryptosystems

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Chinese Physics B 2022年第9期31卷 293-300页

作者： Xiao-Gang Wang hao-Yu wei Department of Applied Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Optical Engineering Zhejiang A&F UniversityHangzhou 311300China

The two types of nonlinear optical cryptosystems(NOCs)that are respectively based on amplitude-phase retrieval algorithm(APRA)and phase retrieval algorithm(PRA)have attracted a lot of attention due to their unique mechanism of encryption process and remarkable ability to resist common *** this paper,the securities of the two types of NOCs are evaluated by using a deep-learning(DL)method,where an end-to-end densely connected convolutional network(DenseNet)model for cryptanalysis is *** proposed DL-based method is able to retrieve unknown plaintexts from the given ciphertexts by using the trained DenseNet model without prior knowledge of any public or private *** results of numerical experiments with the DenseNet model clearly demonstrate the validity and good performance of the proposed the DL-based attack on NOCs.

关键词： optical encryption nonlinear optical cryptosystem deep learning phase retrieval algorithm

Nonlinear dynamics of a flapping rotary wing:Modeling and optimal wing kinematic analysis

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Chinese Journal of Aeronautics 2018年第5期31卷 1041-1052页

作者： Qiuqiu WEN Shijun GUO hao LI wei DONG School of Aerospace Beijing Institute of Technology Centre for Aeronautics SATM Cranfield University

The analysis of the passive rotation feature of a micro Flapping Rotary Wing（FRW）applicable for Micro Air Vehicle（MAV） design is presented in this paper. The dynamics of the wing and its influence on aerodynamic performance of FRW is studied at low Reynolds number（~10~3）.The FRW is modeled as a simplified system of three rigid bodies： a rotary base with two flapping wings. The multibody dynamic theory is employed to derive the motion equations for FRW. A quasi-steady aerodynamic model is utilized for the calculation of the aerodynamic forces and moments. The dynamic motion process and the effects of the kinematics of wings on the dynamic rotational equilibrium of FWR and the aerodynamic performances are studied. The results show that the passive rotation motion of the wings is a continuous dynamic process which converges into an equilibrium rotary velocity due to the interaction between aerodynamic thrust, drag force and wing inertia. This causes a unique dynamic time-lag phenomena of lift generation for FRW, unlike the normal flapping wing flight vehicle driven by its own motor to actively rotate its wings. The analysis also shows that in order to acquire a high positive lift generation with high power efficiency and small dynamic time-lag, a relative high mid-up stroke angle within 7–15° and low mid-down stroke angle within -40° to -35° are necessary. The results provide a quantified guidance for design option of FRW together with the optimal kinematics of motion according to flight performance requirement.

关键词： Dynamic model Dynamic time-lag Flapping rotary wing Kinematics of wings Passive rotation Strike angle

Mechanisms for the link between onset and duration of open water in the Kara Sea

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Acta Oceanologica Sinica 2021年第11期40卷 119-128页

作者： Chunming Dong Hongtao Nie Xiaofan Luo hao wei wei Zhao School of Marine Science and Technology Tianjin UniversityTianjin 300072China

The sea ice conditions in the Kara Sea have important impacts on Arctic shipping,oil and gas production,and marine environmental *** this study,sea ice coverage(C_(R))less than 30%is considered as open water,its onset and end dates are defined as T_(open)and T_(close),*** sea ice melt onset(T_(melt))is defined as the date when ice-sea freshwater flux initially changes from ice into the ***-based sea ice concentration(SIC)from 1989 to 2019 shows a negative correlation between T_(open)and T_(close)(r=-0.77,p<0.01)in the Kara *** phenomenon is also obtained through analyzing the hindcast simulation from 1994 to 2015 by a coupled ocean and sea-ice model(NAPA1/4).The model results reveal that thermodynamics dominate the sea ice variations,and ice basal melt is greater than the ice surface *** budget estimation suggests that the heat flux is significant correlated with T_(open)(r=-0.95,p<0.01)during the melt period(the duration of multi-year averaged T_(melt)to T_(open))influenced by the sea ice ***,this heat flux is also suggested to dominate the interannual variation of the heat input during the whole heat absorption process(r=0.81,p<0.01).The more heat input during this process leads to later T_(close)(r=0.77,p<0.01).This is the physical basis of the negative correlation between T_(open)and T_(close).Therefore,the duration of open water can be predicted by T_(open)and thence support earlier planning of marine activities.

关键词： sea ice open water onset duration of open water heat budget Kara Sea

FBCRI Based Real-time Path Planning for Unmanned Aerial Vehicles in Unknown Environments with Uncertainty

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机器人 2013年第6期35卷 641-650页

作者： LIU wei hao Peng ZHENG Zheng CAI Kaiyuan School of Automation Science and Electrical Engineering Beihang University Science and Technology on Aircraft Control Laboratory High-Tech Institute of Xi'an

This paper presents an FBCRI(feedback based compositional rule of inference)based novel path planning method to satisfy the requirements of real-time navigation,smoothness optimization and probabilistic obstacle *** local path-searching behaviors in regional ranges and global goal-seeking behaviors in holistic ranges,the method infers behavior weights using fuzzy reasoning embedded with feedback,and then coordinates the behaviors to generate new reference *** view of the deterministic decisions and the uncertain states of a UAV(unmanned air vehicle),chance constraints are adopted to probabilistically guarantee the UAV’s safety at a required *** results in representative scenes prove that the method is able to rapidly generate convergent paths in obstacle-rich environments,as well as highly improve the path quality with respect to smoothness and probabilistic safety.

关键词： unmanned aerial vehicle path planning fuzzy reasoning FBCRI(feedback based compositional rule of inference) uncertainty