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Distribution,abundance,and realized niches of meroplankton by two different mesh size nets during spring 2017 in the Southern Yellow Sea,China
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作者 Shuangyan ZHANG Fang ZHANG +3 位作者 Xiaoxia SUN Dongjie GUO Jianfeng WANG Song SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1540-1556,共17页
Meroplankton play a crucial role in both benthic and pelagic ecosystems.Existing quantitative research on estimating the quantities of meroplankton groups is both underrepresented and inaccurate.To investigate and eva... Meroplankton play a crucial role in both benthic and pelagic ecosystems.Existing quantitative research on estimating the quantities of meroplankton groups is both underrepresented and inaccurate.To investigate and evaluate the influence of varying mesh sizes(505 and 160μm)on the sampling efficiency of meroplankton,we conducted an examination using two commonly used plankton nets during the spring season in the Southern Yellow Sea(SYS).Our study revealed a total of 12 meroplankton groups,with 9 groups identified in the 505-μm mesh nets and 11 groups in the 160-μm mesh nets.The results demonstrated the superior collection efficiency of the 160-μm net compared to the 505-μm net across the majority of meroplankton groups.Furthermore,we focused on exploring the abundance,distribution patterns,and realized niches of meroplankton collected by the two mesh size nets,and observed that the distribution of meroplankton closely resembled the distribution of possible benthic adults in the SYS.Correlation analysis of the six dominant groups collected in the 160-μm mesh nets revealed that seawater temperature and salinity emerged as the key environmental factors driving variations in meroplankton abundance within the SYS.This study also found that a smaller mesh size net does not necessarily capture meroplankton more comprehensively.A comprehensive understanding of the ecological characteristics of meroplankton requires the combination of two types of nets for research.Our research significantly advances our understanding of the quantification,abundance,and distribution of meroplankton,serving as a valuable contribution to the broader landscape of detailed quantitative meroplankton studies. 展开更多
关键词 meroplankton plankton net mesh size collection efficiency distribution characteristic realized niches
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Design of a Metasurface Antenna Based on Characteristic Mode Theory
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作者 HE Huan 《电讯技术》 北大核心 2024年第10期1561-1568,共8页
A novel metasurface antenna consisting of 5×5 rectangular patch elements is presented.Thestructure with and without the central element are both analyzed by the Characteristic Mode Theory(CMT).The developed mutua... A novel metasurface antenna consisting of 5×5 rectangular patch elements is presented.Thestructure with and without the central element are both analyzed by the Characteristic Mode Theory(CMT).The developed mutually orthogonal principal modes of the optimized periodic patch structure areexcited by a center-feed dipole.A differential feeding network is employed to realize impedance matching.Prototype with profile height of 0.07λ_(0)(λ_(0)is the wavelength in free space at the lowest operatingfrequency)is fabricated and assembled to verify the simulation results.The measured results show that thereflectance coefficient of proposed matesurface antenna is less than-10 dB in the whole operating bandrange from 4.2 GHz to 5.5 GHz,a relative bandwidth of 26.8%is achieved,and the maximummeasured realized gain is more than 9 dBi with a maximum radiation efficiency of 90%.The designprovides a guideline on the application of characteristic modes(CMs)to radiation problems. 展开更多
关键词 metasurface antenna characteristic mode theory dipole antenna realized gain
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Metaverse Upsurge Drives Virtual Human Industry to Upgrade
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作者 Yu Li 《China's Foreign Trade》 2024年第1期51-52,共2页
The concept of a virtual human is rapidly fermenting with the boom of the metaverse in 2020.In March 2021,Roblox,a game company focusing on the socialization of teenagers’games and the free realization of UGC,went pu... The concept of a virtual human is rapidly fermenting with the boom of the metaverse in 2020.In March 2021,Roblox,a game company focusing on the socialization of teenagers’games and the free realization of UGC,went public.In its prospectus,Roblox is defined as the concept of the metaverse.Under this background,as the direct embodiment of“virtual identity”and“virtual reality coexisting”under the concept of the metaverse,the emerging definition of virtual human and its representative virtual image has gradually caught the attention of the public. 展开更多
关键词 REALIZATION HUMAN SURGE
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Practices and Reflections of CNOOC on Building World-Class Enterprises
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作者 Wu Rihan He Xu +3 位作者 Li Shuai Yang Xueqin Wei Yujing Zhang Yuqi 《China Oil & Gas》 CAS 2024年第2期38-51,共14页
At present,China is facing new strategic opportunities as well as risks and challenges in its development.Faced with the challenges brought by current global major risks,China urgently needs to build a group of world-... At present,China is facing new strategic opportunities as well as risks and challenges in its development.Faced with the challenges brought by current global major risks,China urgently needs to build a group of world-class enterprises as ballast stones.Accelerating the development of a number of world-class enterprises is an important support for China to enhance its comprehensive strength and international competitiveness,and is crucial for the realization of the strategic blueprint for socialist modernization.After more than forty years of reform and opening up,Chinese enterprises have rapidly developed and grown stronger,with their position rising and their influence in the global market increasing continuously.However,Chinese enterprises are“large in size but not yet strong enough”.In this context,this paper systematically analyzes the practical significance and theoretical connotation of building world-class enterprises and the status quo of building world-class enterprises in China and takes CNOOC as an example to deeply analyze the practices of large central enterprises to build world-class enterprises at the levels of group and subsidiaries,providing a reference for Chinese enterprises to accelerate their progress towards world-class enterprises. 展开更多
关键词 ENTERPRISES REALIZATION STRATEGIC
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Pragmatist View of Human Rights:Theoretical Explanations of China’s Human Rights Practice
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作者 YU Xiqiao GUO Dong 《The Journal of Human Rights》 2024年第3期614-636,共23页
The pragmatist view of human rights represents a the-oretical condensation of the Chinese practice in human rights devel-opment.In view of the problem of circular idling between rights and claims caused by the traditi... The pragmatist view of human rights represents a the-oretical condensation of the Chinese practice in human rights devel-opment.In view of the problem of circular idling between rights and claims caused by the traditional view of human rights of focusing on contents and not valuing implementation,social segmentation caused by empty talks on interests and claims while ignoring social develop-ment,and the phenomenon of the issue of human rights completely becoming empty and useless political rhetoric,the pragmatic view of human rights,based on the fact that there is a gap between the claims and realization of human rights,emphasizes that instead of blindly ex-panding the types of rights in term of text,it is better to base on prac-tice and promote the maximum realization of existing rights through development.The pragmatist view of human rights attaches impor-tance to relevant economic,social and cultural basis to promote the realization of human rights,rather than only focusing on the claims themselves;it pays greater attention to enhancing the realization of rights,rather than the distribution of rights under the total limit;it ad-vocates more for cooperativism in the realization of rights,rather than confrontation.The pragmatic concept of human rights takes Marxism as its theoretical basis and the gene of practice and the dimension of development as its theoretical characteristics,and promotes the devel-opment of human rights through the realization of rights. 展开更多
关键词 pragmatist view of human rights rights and claims realization of rights cooperativism development
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Construction of Regional Ecological Capital Operation Mechanism System from the Perspective of Green Economy Development
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作者 Wanxuan WU Jialin LIU Xieyu XIONG 《Meteorological and Environmental Research》 2024年第4期44-48,共5页
Green development has gradually become the main theme of the current world economic development.Green transformation development and cracking the contradiction between ecology and economy need to build an effective ec... Green development has gradually become the main theme of the current world economic development.Green transformation development and cracking the contradiction between ecology and economy need to build an effective ecological capital operation system and mechanism to support,encourage the effective operation of regional ecological capital,promote the appreciation and preservation of ecological capital,and escort the operation.This paper constructs a four-in-one regional ecological capital operation mechanism system,in which the"accumulation mechanism"is the prerequisite,the"conversion mechanism"is the key link,the"compensation mechanism"is an important supplement,and the"incentive mechanism"is the safeguard measure,which aims to ensure the smooth progress of the construction of beautiful China in the new era and realize the socialist modern power. 展开更多
关键词 Green economy Value realization of ecological products Ecological capital operation
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土地耕种
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作者 《疯狂英语(新读写)》 2024年第11期61-72,78-80,共15页
第一部分语言基础(共两节,满分30分)第一节单句填空(共15小题;每小题1分,满分15分)1.We are affected by color more than we realize because color is related to all_(aspect)of our lives.
关键词 LIVES more than realize
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Critical Success Factors for Citizen Development
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作者 Natalie Callinan Martin Perry 《Open Journal of Applied Sciences》 2024年第4期1121-1149,共29页
The purpose of the research was to assess the impact of Citizen Development activities on digital transformation. The research identified eight categories that contribute to the success of Low-code No-code (LCNC) proj... The purpose of the research was to assess the impact of Citizen Development activities on digital transformation. The research identified eight categories that contribute to the success of Low-code No-code (LCNC) projects: 1) Strategy;2) Infrastructure;3) Technology;4) Processes & Procedures;5) Governance;6) Culture;7) People;8) Goals & Metrics and selected six critical success factors from these categories: 1) Operational Efficiency;2) Time Savings;3) Timeframe to Realize Value;4) Employee Engagement;5) Participation;6) Number of Sponsored Ideas. End users of the digital transformation efforts through Citizen Development were asked to assess the six critical success measures in terms of performance and importance criteria. The research results identified that focus should be applied to improving “Timeframe to Realize Value”, on “Operational Efficiency”, and on “Time Savings” to deliver success. 展开更多
关键词 Citizen Development Low-Code No-Code Application Development Digital Transformation Timeframe to Realize Value Employee Engagement
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潜航器微气泡减阻数值模拟方法研究
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作者 詹杰民 陆尚平 +2 位作者 李熠华 李雨田 胡文清 《海洋工程》 CSCD 北大核心 2023年第4期1-11,共11页
近年来微气泡减阻技术应用于水面舰船的相关研究取得重要进展,许多舰船已经采用了此类技术。然而该技术在潜航器上的应用整体上仍处于理论分析和试验测试阶段。以回转体潜航器简化模型为研究对象,利用多孔介质来简化喷气小孔,并结合不... 近年来微气泡减阻技术应用于水面舰船的相关研究取得重要进展,许多舰船已经采用了此类技术。然而该技术在潜航器上的应用整体上仍处于理论分析和试验测试阶段。以回转体潜航器简化模型为研究对象,利用多孔介质来简化喷气小孔,并结合不可压缩水体和可压缩理想气体的流体体积(VOF)方法,建立了Realizableε-k湍流计算模式。通过拖曳试验验证了多孔介质等效喷气小孔的合理性和数值模式的准确性,结合试验和数值结果探究了微气泡减阻技术对潜航器航行阻力的影响。数值结果显示,气泡对潜航器尾流低速区的改变使尾部压力分布产生变化从而导致压差阻力增高。同时气泡可以显著降低其覆盖区域的黏性阻力。并且随着来流速度的提高,气泡覆盖范围扩大,黏性减阻率持续增加。进一步地,建立了加长改进模型,数值模拟结果表明,微气泡减阻技术不仅能大幅减小黏性阻力,还能有效减小模型总阻力。 展开更多
关键词 微气泡减阻 潜航器 拖曳试验 Realizableε-k湍流模式 多孔介质
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圆柱形膛口装置对膛口流场的影响研究
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作者 张文涛 杨臻 +1 位作者 徐健 王国强 《兵器装备工程学报》 CAS CSCD 北大核心 2023年第12期227-233,共7页
为避免后效期燃气对枪口周围的影响,通过改变圆柱形膛口装置的尺寸,运用CFD仿真分析,结合动网格技术和重叠网格技术,使用Realizeable k-ε湍流模型,对膛口流场进行仿真计算,通过同一位置观测点温度判断后效期燃气对周围环境影响程度。... 为避免后效期燃气对枪口周围的影响,通过改变圆柱形膛口装置的尺寸,运用CFD仿真分析,结合动网格技术和重叠网格技术,使用Realizeable k-ε湍流模型,对膛口流场进行仿真计算,通过同一位置观测点温度判断后效期燃气对周围环境影响程度。研究表明:当膛口装置的尺寸设计长径比为1时,能降低40%的膛口气流对周围环境的影响,且相同长径比下,等比例扩大的圆柱形膛口装置能更好的降低对周围环境的影响。 展开更多
关键词 膛口装置 膛口流场 CFD 动网格技术 Realizeable k-ε湍流模型
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风雨场条件下汽车乘员舱气动噪声数值模拟
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作者 宗轶琦 陶海 +2 位作者 沈辉 杨易 罗泽敏 《时代汽车》 2023年第24期18-23,33,共7页
本研究以某汽车为研究对象,基于数值模拟探讨不同降雨量工况下的汽车乘员舱气动噪声声压级水平。采用Realizable k-ε/LES湍流模型来模拟无雨时的单相流流场,再添加离散相模型(DPM)来模拟有雨时的两相流流场,以声类比(FW-H)方法获得了... 本研究以某汽车为研究对象,基于数值模拟探讨不同降雨量工况下的汽车乘员舱气动噪声声压级水平。采用Realizable k-ε/LES湍流模型来模拟无雨时的单相流流场,再添加离散相模型(DPM)来模拟有雨时的两相流流场,以声类比(FW-H)方法获得了不同降雨量下车身表面各子系统的1/3倍频程平均输入激励,采用混合有限元-统计能量分析(FE-SEA)方法获得了驾驶员耳旁气动噪声声压级水平。仿真结果表明:在20-1000Hz频段内,有雨工况下的驾驶员耳旁的声压级在各中心频率处都低于无雨工况,小雨工况和中雨工况下的驾驶员耳旁总声压级较为接近,大雨工况下的驾驶员耳旁总声压级最低。 展开更多
关键词 气液两相流 乘员舱气动噪声 Realizable k-ε/LES 离散相模型 有限元-统计能量分析法 数值模拟
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Highly Tunable Perpendicular Magnetic Anisotropy and Anisotropic Magnetoresistance in Ru-Doped La_(0.67)Sr_(0.33)MnO_(3)Epitaxial Films
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作者 华恩达 戴坤杰 +8 位作者 王庆 叶欢 刘宽 章金凤 鲁京迪 刘楷 金锋 王凌飞 吴文彬 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第7期74-79,共6页
As a prototypical half-metallic ferromagnet,La_(0.67)Sr_(0.33)MnO_(3)(LSMO)has been extensively studied due to its versatile physical properties and great potential in spintronic applications.However,the weak perpendi... As a prototypical half-metallic ferromagnet,La_(0.67)Sr_(0.33)MnO_(3)(LSMO)has been extensively studied due to its versatile physical properties and great potential in spintronic applications.However,the weak perpendicular magnetic anisotropy(PMA)limits the controllability and detection of magnetism in LSMO,thus hindering the realization of oxide-based spintronic devices with low energy consumption and high integration level.Motivated by this challenge,we develop an experimental approach to enhance the PMA of LSMO epitaxial films.By cooperatively introducing 4d Ru doping and a moderate compressive strain,the maximum uniaxial magnetic anisotropy in Ru-doped LSMO can reach 3.0×10^(5)J/m^(3)at 10 K.Furthermore,we find a significant anisotropic magnetoresistance effect in these Ru-doped LSMO films,which is dominated by the strong PMA.Our findings offer an effective pathway to harness and detect the orientations of magnetic moments in LSMO films,thus promoting the feasibility of oxide-based spintronic devices,such as spin valves and magnetic tunnel junctions. 展开更多
关键词 ANISOTROPY HIGHLY REALIZATION
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Deep Underground Energy Storage:Aiming for Carbon Neutrality and Its Challenges
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作者 Chunhe Yang Tongtao Wang 《Engineering》 SCIE EI CAS CSCD 2023年第10期11-14,共4页
1.Definition of deep underground energy storage Deep underground energy storage(DUES)is an important strategic practice for ensuring China’s energy supply,its national defense,and the realization of China’s strategi... 1.Definition of deep underground energy storage Deep underground energy storage(DUES)is an important strategic practice for ensuring China’s energy supply,its national defense,and the realization of China’s strategic goals of achieving a carbon peak and carbon neutrality(CPCN).In 2021,China’s oil and natural gas consumption reached 712 million tonnes and 372.6 billion cubic meters,respectively,while its external dependence reached about 72%and 45%.China’s reserves only met about 30%of the requirements for a safe supply and peak shaving. 展开更多
关键词 UNDERGROUND REALIZATION STRATEGIC
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Intensity-Dependent Dipole Phase in High-Order Harmonic Interferometry
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作者 王力 肖凡 +7 位作者 宋盼 陶文凯 孙旭 王家灿 郑志刚 赵晶 王小伟 赵增秀 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第11期57-61,共5页
High-order harmonics are ideal probes to resolve the attosecond dynamics of strong-field recollision processes.An easy-to-implement phase mask is utilized to covert the Gaussian beam to TEM01 transverse electromagneti... High-order harmonics are ideal probes to resolve the attosecond dynamics of strong-field recollision processes.An easy-to-implement phase mask is utilized to covert the Gaussian beam to TEM01 transverse electromagnetic mode,allowing the realization of two-source interferometry of high-order harmonics.We experimentally measure the intensity dependence of dipole phase directly with high-order harmonic interferometry,in which the driving laser intensity can be precisely adjusted.The classical electron excursion simulations reproduce the experimental findings quite well,demonstrating that Coulomb potential plays subtle roles on movement of electrons for harmonics near the ionization threshold.This work is of great importance for precision measurements of ultrafast dynamics in strong-field physics. 展开更多
关键词 HARMONICS INTERFEROMETRY REALIZATION
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An Improved Whale Optimization Algorithm for Global Optimization and Realized Volatility Prediction
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作者 Xiang Wang Liangsa Wang +1 位作者 Han Li Yibin Guo 《Computers, Materials & Continua》 SCIE EI 2023年第12期2935-2969,共35页
The original whale optimization algorithm(WOA)has a low initial population quality and tends to converge to local optimal solutions.To address these challenges,this paper introduces an improved whale optimization algo... The original whale optimization algorithm(WOA)has a low initial population quality and tends to converge to local optimal solutions.To address these challenges,this paper introduces an improved whale optimization algorithm called OLCHWOA,incorporating a chaos mechanism and an opposition-based learning strategy.This algorithm introduces chaotic initialization and opposition-based initialization operators during the population initialization phase,thereby enhancing the quality of the initial whale population.Additionally,including an elite opposition-based learning operator significantly improves the algorithm’s global search capabilities during iterations.The work and contributions of this paper are primarily reflected in two aspects.Firstly,an improved whale algorithm with enhanced development capabilities and a wide range of application scenarios is proposed.Secondly,the proposed OLCHWOA is used to optimize the hyperparameters of the Long Short-Term Memory(LSTM)networks.Subsequently,a prediction model for Realized Volatility(RV)based on OLCHWOA-LSTM is proposed to optimize hyperparameters automatically.To evaluate the performance of OLCHWOA,a series of comparative experiments were conducted using a variety of advanced algorithms.These experiments included 38 standard test functions from CEC2013 and CEC2019 and three constrained engineering design problems.The experimental results show that OLCHWOA ranks first in accuracy and stability under the same maximum fitness function calls budget.Additionally,the China Securities Index 300(CSI 300)dataset is used to evaluate the effectiveness of the proposed OLCHWOA-LSTM model in predicting RV.The comparison results with the other eight models show that the proposed model has the highest accuracy and goodness of fit in predicting RV.This further confirms that OLCHWOA effectively addresses real-world optimization problems. 展开更多
关键词 Whale optimization algorithm chaos mechanism opposition-based learning long short-term memory realized volatility
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Do U.S.economic conditions at the state level predict the realized volatility of oil‑price returns?A quantile machine‑learning approach
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作者 Rangan Gupta Christian Pierdzioch 《Financial Innovation》 2023年第1期645-666,共22页
Because the U.S.is a major player in the international oil market,it is interesting to study whether aggregate and state-level economic conditions can predict the subse-quent realized volatility of oil price returns.T... Because the U.S.is a major player in the international oil market,it is interesting to study whether aggregate and state-level economic conditions can predict the subse-quent realized volatility of oil price returns.To address this research question,we frame our analysis in terms of variants of the popular heterogeneous autoregressive realized volatility(HAR-RV)model.To estimate the models,we use quantile-regression and quantile machine learning(Lasso)estimators.Our estimation results highlights the dif-ferential effects of economic conditions on the quantiles of the conditional distribution of realized volatility.Using weekly data for the period April 1987 to December 2021,we document evidence of predictability at a biweekly and monthly horizon. 展开更多
关键词 Oil price Realized volatility Economic conditions indexes Quantile Lasso Prediction models
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Moderate scale and realization potential of new citrus-planting business entities in hilly and mountainous areas in China
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作者 ZHANG Xuan-yun ZHANG Shi-chao +3 位作者 LIU Jing-yu RAN Na ZHANG Xiang NING Qi-wen 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2315-2343,共29页
The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale ... The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale operations cannot be fully achieved in a short period of time,and the centralized and continuous scale of operations cannot be realized in China.In addition,with increasingly strict farmland protection and agricultural land use control systems,the issues of nongrain production and nonagricultural cultivated land use have become increasingly restricted.Thus,it is quite necessary to determine the appropriate scale of operations and the means to achieve moderately scaled operations for the new business entities.On the basis of microsurvey data for 108 new citrus-planting business entities in the modern agricultural park in the Chongqing's Jiangjin District,an area with long citrus-planting history,we measured the moderate scale of new citrus-planting business entities to maximize profit using a translog growth model.According to the projection pursuit model,we evaluated the suitability conditions of citrus planting in garden land,woodland,grassland,and general cultivated land in the study area.We then explored the potential for new moderate-scale business entities within different farming radii.The results showed that large-scale planting conditions of citrus in garden land,forest land,grassland,and general cultivated land in the study area were suitable,and the proportion of high-suitable and mediumsuitable land was 73.42%.Under the existing social and economic conditions,the moderate scale of new citrus-planting business entities in the study area was 1.8–2.7 hm^(2).In particular,its rankings from large to small were agricultural enterprises(17.19–25.78 hm^(2)),farmer cooperatives(16.88–25.33 hm^(2)),big growers and breeders(6.39–9.59 hm^(2)),and family farms(5.02–7.53 hm^(2)).In the sample of 108 households,only 47.22%of the entities achieved moderate-scale operation,of which 25%of the entities achieved a scale greater than moderate operation.However,52.78%of the entities achieved a scale of less than moderate operation.These entities would have to transfer the surrounding adjacent garden land,forest land,grassland,or general cultivated land to achieve largescale land management.The land area of the adjacent gardens in a 1000 m farming radius could meet the moderate-scale operation demand of the vast majority of new business entities.For the vast majority of new business entities,the land area of the adjacent woodland,grassland,and general cultivated land could supplement the garden land to achieve moderate-scale operation in a 500 m farming radius.If the land area with moderate suitability and high suitability is prioritized,the land area in the adjacent gardens in the 1000 m farming radius could meet the moderate-scale operation demand for the vast majority of new business entities.Within the 500 m farming radius,the vast majority of new business entities have achieved moderate-scale operations if the land area adjacent to forest land,grassland,and general arable land was supplemented by gardens;however,a few entities could not achieve moderate-scale operations.From the village perspective,gardens were prioritized.Sixteen villages had planting areas and planting suitability that exceeded the average level of the study area,accounting for 23.53%.If combined with the reserve potential of the garden land,eight villages could improve their potential,accounting for 11.76%.Therefore,the conditions of large-scale citrus planting in the study area should be further improved,and the scale expansion of new citrus-planting business entities should receive additional scientific guidance. 展开更多
关键词 Land management Hilly and mountainous areas Agricultural business entities Moderate operation scale Agricultural land resources Realizing potential
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The predictive power of Bitcoin prices for the realized volatility of US stock sector returns
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作者 Elie Bouri Afees A.Salisu Rangan Gupta 《Financial Innovation》 2023年第1期1717-1738,共22页
This paper is motivated by Bitcoin’s rapid ascension into mainstream finance and recent evidence of a strong relationship between Bitcoin and US stock markets.It is also motivated by a lack of empirical studies on wh... This paper is motivated by Bitcoin’s rapid ascension into mainstream finance and recent evidence of a strong relationship between Bitcoin and US stock markets.It is also motivated by a lack of empirical studies on whether Bitcoin prices contain useful information for the volatility of US stock returns,particularly at the sectoral level of data.We specifically assess Bitcoin prices’ability to predict the volatility of US composite and sectoral stock indices using both in-sample and out-of-sample analyses over multiple forecast horizons,based on daily data from November 22,2017,to December,30,2021.The findings show that Bitcoin prices have significant predictive power for US stock volatility,with an inverse relationship between Bitcoin prices and stock sector volatility.Regardless of the stock sectors or number of forecast horizons,the model that includes Bitcoin prices consistently outperforms the benchmark historical average model.These findings are independent of the volatility measure used.Using Bitcoin prices as a predictor yields higher economic gains.These findings emphasize the importance and utility of tracking Bitcoin prices when forecasting the volatility of US stock sectors,which is important for practitioners and policymakers. 展开更多
关键词 Bitcoin prices S&P 500 index US sectoral indices Realized volatility prediction Economic gains
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Research on How to Strengthen Women’s Right to Employment in MNEs
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作者 YAN Yuxin 《Psychology Research》 2023年第3期123-130,共8页
Women’s equal employment encounters challenges such as gender-blindness in legal protection,a cultural environment where traditional conservative views are at odds with women’s equal employment,the absence of intern... Women’s equal employment encounters challenges such as gender-blindness in legal protection,a cultural environment where traditional conservative views are at odds with women’s equal employment,the absence of international and domestic gender discrimination intervention links,and invisible gender discrimination.Unequal or inequitable treatment can marginalize women and make it impossible for them to contribute to social and economic development as active members of society.Invisible gender bias in the employment process is increasingly prominent.This paper examines the current situation of women’s equal employment and the inadequacy of relevant laws and regulations from both international and Chinese perspectives.The problem of the composition of social structures and the cultural environment which is contrary to the equality of employment of women is the main reason for the current situation and the inadequacy of laws.The solution to the above problems can be found in three perspectives which are legislative improvements,legal and regulatory level improvement,and perfection of multinational enterprise responsibility.Research from the perspective of legal interpretation tends to focus on formal equality in women’s employment.‘‘MNEs’’means multinational enterprise.This makes it difficult to achieve the transition to substantive equality.Research from a public policy perspective often invites criticism of government overreach and the injustice of proposing policies that favor women’s interests.In order to better guarantee an equal employment environment for women,this paper proposes creating a gender-disaggregated employment statistics and monitoring system based on firm type and size,thereby improving the intervention mechanism of gender discrimination in employment linked by the government,social organizations,and the media. 展开更多
关键词 GENDER DISCRIMINATION in EMPLOYMENT market COMPETITION realization mechanism
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Landscape Aesthetic Characteristics of Wulingyuan World Natural Heritage Property and Realization Path of Aesthetic Education Value
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作者 LUO Shui XIAO Hua XIAO Shizhen 《Journal of Landscape Research》 2023年第5期79-84,88,共7页
Wulingyuan is a world natural heritage property mainly dominated by rare quartz sandstone peak forest landscape at home and abroad and supplemented by karst landscapes,with a large number of geological and historical ... Wulingyuan is a world natural heritage property mainly dominated by rare quartz sandstone peak forest landscape at home and abroad and supplemented by karst landscapes,with a large number of geological and historical sites,biological and ecological landscape and unique cultural landscapes.Preserving the secluded and beautiful scenery environment,biological environment and ecosystem of subtropical zone,Wulingyuan presents a splendid and magnificent landscape,with high aesthetic value,and becomes an important practice base of aesthetic education.The aesthetic education value of Wulingyuan World Natural Heritage Property can be realized by systematically studying and presenting the aesthetic education value of Wulingyuan World Natural Heritage Property,developing a series of aesthetic education courses to lead tourists into the world of Wulingyuan aesthetic education,carrying out a series of popular science activities of“Wulingyuan World Natural Heritage Property Entering Campus”,and incorporating into the aesthetic education curriculum system of schools,etc.This paper analyzes the landscape aesthetic characteristics of Wulingyuan World Natural Heritage Property thoroughly,which indicates the direction for realizing the aesthetic education value of the property,and also provides a reference for realizing the aesthetic education value of similar world natural heritage property. 展开更多
关键词 World natural heritage property Landscape aesthetic characteristics Aesthetic education value Realization path Wulingyuan
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