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Climate instability during the last glaciation recorded in the Yuanbu loess section

Progress in Natural Science:Materials International 2009年第4期19卷 453-459页

作者： Yimeng Chen Department of economics & management, huizhou {3.,{4., china [a]Department of economics & management Huizhou University Huizhou 516007 China

Abrupt events within the Linxia Yuanbu loess section in the western Loess Plateau in china were investigated. The climatic proxy index of the content of mean grain-size and >4.lm grain-size fraction of the section was used as a climatic indicator, and a moving average method was applied in the statistical analysis to extract the abrupt events recorded in the section. It was found that the loess of the last glaciation recorded not only the abrupt events teleconnected with the high-latitude North Atlantic and Greenland regions but also as many as 15 abrupt events in addition to the Heinrich (H) and Younger Dryas (YD) events. This indicates that abrupt climate changes were typical of the climate changes occurring in the Loess Plateau during the last glaciation. The widely recognized mechanisms of the abrupt climate changes, including the heat transfer theory of the North Atlantic Ocean, the atmospheric circulation theory, and the theory of the interac- tion between low-latitude ocean and the atmosphere remains to be discussed. Perhaps this problem could be resolved by revealing the rela- tion between the evolution of the features of the East Asian monsoon climate and the climate in the surrounding areas. Through a detailed study of the features of the Heinrich and YD events, criteria on which the abrupt events recorded in the loess could be distinguished were tentatively defined. The events were associated with a large grain size, high carbonate content, high lightness, low susceptibility, low redness and low yellowness. In addition, the variation amplitude of the adjacent peak and valley on the curve of the content of the mean grain-size and >4. lm grain-size fraction was larger than 3.4.lm and the content of >4. lm grain-size fraction was larger than 2.0 lm. Lastly, the length of the variation time was less than 500 years. If all these criteria were met, the event was viewed as an abrupt event.

关键词： Climate instability Moving average Abrupt event Last glaciation Loess section

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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4.and Gong Huili1,2(1. MOE and Key Laboratory of Resources Environment and GIS of Beijing, Beijing 10003., china 2. Key Laboratory of 3. information Acquisition and Application, The Capital Normal {4., Beijing 10003., china 3. Department of {3. & management of huizhou {4., huizhou 516007, china 4. Key Laboratory of Western china’s Environmental Systems, Ministry of Education, Lanzhou {4., Lanzhou 73.000, china) MOE and Key Laboratory of Resources Environment and GIS of Beijing Beijing 100037 China Key Laboratory of 3. information Acquisition and Application The Capital Normal University Beijing 100037 China Department of economics & management of huizhou {3. Huizhou 516007 China Key Laboratory of Western china’s Environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4.of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4.are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4.is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14. age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

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A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU School of economics and management,Wuhan university,Wuhan 4.3}072,{3. School of economics and management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

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The Establishment of Cultivation Mode of Applied Talents in Local Universities

The Establishment of Cultivation Mode of Applied Talents in ...

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第十一届全国经济管理院校工业技术学研究会

作者： Min ZHANG 1,Yingping WU 2,Jing LUO 3.1 economics and management Department,huizhou {3.,huizhou,china 2 Music Department,huizhou {3.,huizhou,china 3.economics and management Department,huizhou {3.,huizhou,china

Applied talents are those inter-disciplinary talents,which fall between academic talents and vocational *** management in local universities should aim at cultivating advanced professionals,who not only have creative minds and practical skills but also can apply themselves to local economic and social development *** pursuance of this aim universities should reform and innovate their training plans,curriculum setting methodology,teaching methods and medium as well as practice *** outcome should be to establish a talent cultivation mode that meets local economic and social development needs,and fosters high-quality applied logistics management talents.

关键词： Local university Logistics management Cultivation

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ORDERED WEIGHTED DISTANCE MEASURE

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 432-445页

作者： Zeshui XU~1 Jian CHEN~2 1 School of economics and management,Southeast university,Nanjing,Jiangsu 210096,{3. 2 School of economics and management,Tsinghua university,Beijing,100084.{3. School of economics and management Southeast University Nanjing Jiangsu 210096 China School of economics and management Tsinghua University Beijing 100084 China

The aim of this paper is to develop an ordered weighted distance(OWD) measure,which is the generalization of some widely used distance measures,including the normalized Hamming distance, the normalized Euclidean distance,the normalized geometric distance,the max distance,the median distance and the min distance,***,the ordered weighted averaging operator,the generalized ordered weighted aggregation operator,the ordered weighted geometric operator,the averaging operator,the geometric mean operator,the ordered weighted square root operator,the square root operator,the max operator,the median operator and the min operator are also the special cases of the OWD *** methods depending on the input arguments are given to determine the weights associated with the OWD *** prominent characteristic of the OWD measure is that it can relieve(or intensify) the influence of unduly large or unduly small deviations on the aggregation results by assigning them low(or high) *** desirable characteristic makes the OWD measure very suitable to be used in many actual fields,including group decision making,medical diagnosis, data mining,and pattern recognition,***,based on the OWD measure,we develop a group decision making approach,and illustrate it with a numerical example.

关键词： Group decision making ordered weighted distance(OWD) measure aggregation operator

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Research on Retailer’s Financial and Operation Decisions Based on Strategic Customer

Research on Retailer’s Financial and Operation Decisions Ba...

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2012 National Conference on Information Technology and Computer Science

作者： LIU Heng Department of economics and management huizhou {3. huizhou,china

This paper studies retailer’s decision and financial institution’s decision based on the strategic customer when retailer accepts financial service from financial *** shows that financing rate increases with the wholesale price and the average rate of return on investment increasing and decreases with the retailer’s own funds increasing,and retailer’s ordering quantity with finance service is higher than that of without finance service,and retailer and financial institution both get more the expected profit,and strategic customers get more ***,a numerical example is validated.

关键词： financial services strategic customer financing rate

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计算领域的论文数据共享与可重复性问题分析

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图书情报工作 2024年第17期68卷 3-15页

作者：于倩倩孟银涛钱力刘会洲中国科学院文献情报中心北京100190 中国科学院大学经济与管理学院信息资源管理系北京100190 国家新闻出版署学术期刊新型出版与知识服务重点实验室北京100090 国际关系学院图书馆北京100091 中国科学院过程工程研究所北京100190

[目的/意义]计算可重复是可靠和可信研究的基石,对计算领域的论文数据共享政策、数据可用性和可重复性方法进行调查分析,为促进数据共享及解决计算可重复问题提供参考。[方法/过程]采用网站调研法和内容分析法,分析期刊、会议的数据共... 详细信息

[目的/意义]计算可重复是可靠和可信研究的基石,对计算领域的论文数据共享政策、数据可用性和可重复性方法进行调查分析,为促进数据共享及解决计算可重复问题提供参考。[方法/过程]采用网站调研法和内容分析法,分析期刊、会议的数据共享政策;采用网络爬虫法,获取期刊论文数据的可用性声明,对数据可用性进行分析;并梳理和总结计算可重复的方法。[结果/结论]计算领域大多数期刊、超半数会议有数据共享政策,但数据共享态度的强度还有待提升。越是高水平的期刊或会议,越可能有数据共享政策。相较于期刊关注数据共享问题,会议更关注计算可重复问题。数据可用性声明促进了数据共享,但数据共享实践与数据共享政策要求还存在差距。计算可重复方法包括鼓励或要求数据共享、专家审查、设置奖励、设置论文提交清单、征集可重复性论文等。

关键词：期刊论文会议论文数据共享计算可重复

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融合ChatGPT数据增强的学术论文语步识别方法研究

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图书情报工作 2024年第17期68卷 84-94页

作者：许钦亚薛秋红钱力刘会洲刘鲁静中国科学院文献情报中心北京100190 中国科学院大学经济与管理学院信息资源管理系北京100190 中国电子科技集团公司信息科学研究院北京100086 国家新闻出版署学术期刊新型出版与知识服务重点实验室北京100190 中国科学院过程工程研究所北京100190 中国科学院深圳先进技术研究院碳中和技术研究所深圳518055

[目的/意义]学术论文的语步结构对读者深入理解内容和快速定位关键信息具有重要作用,本文旨在研究全文语步识别方法,以快速获取学术论文的核心内容,推动智能化的语义检索。[方法/过程]在当前语步识别方法方面的相关研究的基础上,提出一... 详细信息

[目的/意义]学术论文的语步结构对读者深入理解内容和快速定位关键信息具有重要作用,本文旨在研究全文语步识别方法,以快速获取学术论文的核心内容,推动智能化的语义检索。[方法/过程]在当前语步识别方法方面的相关研究的基础上,提出一种融合ChatGPT数据增强和预训练语言模型的细粒度语步识别模型SciBERT-HAMI模型。该模型利用原始文本,通过ChatGPT大模型进行语料扩充,以增加训练数据的多样性和数量;使用分层神经网络模型学习论文的“词—句—章节”语义特征表示,以捕捉不同层次的语义信息;将SciBERT的词嵌入表示作为输入,并使用分层神经网络模型与FocalLoss损失函数进行细粒度语步识别模型训练。[结果/结论]结合ChatGPT数据增强策略,SciBERT-HAMI-DA模型在CoreSC和AZ数据集的F1值分别为0.73.和0.74.,对比实验表明,所提模型在论文全文细粒度语步识别任务上性能得到有效提升,并通过消融实验验证数据增强和模型组件的有效性。融合预训练语言模型与ChatGPT数据增强,全文语步识别模型的预测效果得到有效提升,有助于推动学术研究的自动化与智能化。

关键词：语步识别 ChatGPT 数据增强 SciBERT

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Adaptive neuro fuzzy inference system for classification of water quality status

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Journal of Environmental Sciences 2010年第12期22卷 1891-1896页

作者： Han Yan,Zhihong Zou,Huiwen Wang School of economics and management,Beihang university,Beijing 100191,{3. [a] School of economics management Beihang University Beijing 100191 China

An adaptive neuro fuzzy inference system was used for classifying water quality status of river. It applied several physical and inorganic chemical indicators including dissolved oxygen, chemical oxygen demand, and ammonia-nitrogen. A data set （nine weeks, total 84. observations） was collected from 100 monitoring stations in all major river basins in china and used for training and validating the model. Up to 89.59% of the data could be correctly classified using this model. Such performance was more competitive when compared with artificial neural networks. It is applicable in evaluation and classification of water quality status.

关键词： adaptive neuro fuzzy inference system artificial neural networks water quality status classification

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ENTROPY,INFORMATION,NOISE-STUDIES ON SYSTEM EVOLUTION

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Systems Science and Systems Engineering 2003年第1期12卷 2-12页

作者： Weimin ZHENGSchool of economics and management Tsinghua university. Beijing 100084.{3. School of economics and management Tsinghua University

Universe, ecosystem, social system, etc. are evolving systems. The evolving processes of these systems have gradual small changes and rapid drastic changes with uncertainties under the constraints of environment. Systems, as a whole, are evolving toward complexity, diversity and variety with fluctuations and jumps. New order emerges from 'mutations'. The evolution is both chance-dependent and path-dependent. In this paper three basics: entropy, information and noise are emphasized with regard to system evolution which is a field that can give people wisdom to solve system problems with domain knowledge.

关键词： Entropy information noise

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