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基于网络Index DEA的多阶段投资组合效率评价研究

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湖南商学院学报 2016年第2期23卷 98-103页

作者：周忠宝罗咪肖和录金倩颖湖南大学工商管理学院湖南长沙410082

数据包络方法(DEA)近些年来被广泛应用于评价投资组合绩效,然而大多数已有DEA投资组合评价模型都将投入和产出设为期望的指标。本文首先对输入、输出类型进行了判定,在风险和收益两大指标的基础上,构建网络Index DEA投资可能集和投资组... 详细信息

数据包络方法(DEA)近些年来被广泛应用于评价投资组合绩效,然而大多数已有DEA投资组合评价模型都将投入和产出设为期望的指标。本文首先对输入、输出类型进行了判定,在风险和收益两大指标的基础上,构建网络Index DEA投资可能集和投资组合评价模型。最后,选取20支我国股票型基金进行实证分析,说明本文所提出的模型的合理性与可行性。

关键词：基金绩效非期望产出 Index DEA模型网络DEA模型

A Comparative Study on Emulsion Polymerization Processes of Styrene Initiated by Water-soluble and Oil-soluble Initiators

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Chinese Journal of Polymer Science 2019年第2期37卷 142-148页

作者： xiao-Jing Liu Yu-he Tian Yang-Cheng lu State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University

The solubility of initiator determines its distribution and the roles played in emulsion polymerization as well as the final products, but this is still lack of systematic investigation. The present work focuses on this issue by comparing the kinetic behaviors and product properties of styrene emulsion polymerization initiated by 2,2-azoisobutyronitrile(AIBN) and potassium persulphate(KPS).Compared to KPS-initiated emulsion polymerization, the AIBN-initiated polymerization was found to be insensitive to the type of emulsifier, and have high polymerization rate as well as narrow molecular weight distribution and particle size distribution. This result indicates the effective free radicals are generated in micelles or colloids, which could decrease the proportion of homogeneous nucleation and make the process and product more controllable. As a consequence, there is a linear relationship between molecular weight of product and AIBN concentration in lg-lg coordinate. It provided a reference for the preparation of latexes with specified molecular weight and supported the possibility of the coexistence of multiple free radicals in one micelle or colloid when using oil-soluble initiator.

关键词： Emulsion polymerization Oil-soluble initiator Water-soluble initiator Styrene Reaction mechanism

Thermodynamic modeling of Cr-Al-C and Ni-Al-C systems for low-density steels

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Journal of Iron and Steel Research International 2020年第10期27卷 1190-1199页

作者： Wei-sen Zheng Yan-lin he xiao-gang lu State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

The so-called low-density steels have generated a lot of interests with their high specific strength and ductility due to the addi-tion of the light element *** order to accelerate the low-density steel design,a thermodynamic database has been developedwithin the present author *** Al-containing systems,i.e.,Cr-Al-Cand Ni-Al-C,were modeled and optimirzed with CALPHAD approach based on the reliable binary *** Cr-Al-C,system,the Gibbs energy of Cr2AlC phasewas described by a temperature-dependent polynomial with the aid of the experimental data on the heat capacity,instead of estimating heat capacity from Ncumann-Kopp *** incongruent melting temperature of Cr2AlC is 1762 K with theinvariant reaction of liquid+Cr3C2+Al4C3→*** phase equilibria between Cr2AlC and binary phases were wellreproduced by using the present model *** Ni-Al-C system,the liquid,fec and bec phases have been optimizedto fit the carbon solubility in these three phases.A good agreement between the calculated and experimental data has beenobtained using the present description of Ni-Al-C *** reliable descriptions of the two ternary systems developedin the present work can be implemented into the thermodynamic database for low-density steels.

关键词： Cr-Al-C system Ni-Al-C system Thermodynamic model CALPHAD Low-density steel

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北京某教学医院医学生健康素养认知情况研究

中国城乡企业卫生 2021年第2期36卷 20-23页

作者：孙思伟白杨何小璐张霞北京大学第六医院北京大学精神卫生研究所国家卫生健康委员会精神卫生学重点实验室(北京大学)国家精神心理疾病临床医学研究中心(北京大学第六医院)党委院长办公室北京100191

目的了解北京某教学医院医学研究生对自身和患者健康素养认知情况。方法采用便利取样的方法,选取2015年9月在北京市某高校教学医院在读的临床医学专业研究生80名进行问卷调查。结果共收到有效问卷71份,有效回收率为88.75%。医学学习时长... 详细信息

目的了解北京某教学医院医学研究生对自身和患者健康素养认知情况。方法采用便利取样的方法,选取2015年9月在北京市某高校教学医院在读的临床医学专业研究生80名进行问卷调查。结果共收到有效问卷71份,有效回收率为88.75%。医学学习时长为(4.68±2.55)年,调查对象研究素养平均得分为(72.14±13.86)分。调查发现医学研究生在基本知识和理念、健康生活方式与行为和健康技能三个方面健康素养的平均得分分别为(37.82±7.10)、(20.24±3.88)和(17.77±4.46)分;科学健康观、传染病防治素养、慢性病防治素养、安全与急救素养、基本医疗素养和健康信息素养六类健康问题素养的得分分别为(14.86±2.64)、(9.00±2.23)、(15.35±3.26)、(15.56±3.35)、(11.72±3.01)和(9.46±2.70)分。对于健康素养水平,只有19名、占26.76%,实际得分和估计的得分一致,有52名,占73.24%的研究生对自身的健康素养水平认知与实际不符。具有健康素养(健康素养得分≥80分)的医学研究生占比为29.58%,有95.77%的调查对象对研究生群体的健康素养水平认知与研究生实际的健康素养水平不一致,有81.69%的调查对象对患者群体的健康素养水平评估不准确。结论医学研究生的健康素水平相对较高,但对自身和患者的健康素养水平认知有误,应加强医学研究生健康素养知识的培训和教育。

关键词：医学研究生患者健康素养认知

公立医院开展医学科普的必要性和运营思路探索

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中国城乡企业卫生 2024年第5期39卷 11-14页

作者：李怡雪何小璐孙思伟北京大学第六医院/北京大学精神卫生研究所党委院长办公室北京100191

目的公立医院作为医疗卫生行业系统的主力军,应充分承担医学科普工作的职责,本文拟探索公立医院开展医学科普的必要性,为公立医院开展医学科普工作提供科学、合理的运营策略。方法通过查阅国家政策文件和近些年相关领域文献,结合当前新... 详细信息

目的公立医院作为医疗卫生行业系统的主力军,应充分承担医学科普工作的职责,本文拟探索公立医院开展医学科普的必要性,为公立医院开展医学科普工作提供科学、合理的运营策略。方法通过查阅国家政策文件和近些年相关领域文献,结合当前新媒体日益发展和新一轮医改大潮兴起的背景,探索分析公立医院开展医学科普工作的必要性,并提出相应的运营建议。结果公立医院开展医学科普工作将进一步全面推进健康中国战略实施,满足人民群众健康需求,有助于构建和谐医患关系、打造医院金字招牌,同时是识别“伪科普”的重要一环。公立医院可通过聚焦时事热点、完善人才培养、开展精准科普、善用媒体、完善激励措施、创新科普形式等措施助推医学科普工作的开展。结论公立医院开展医学科普势在必行,在政策助推下应进一步完善团队建设,创造生动科普,打造健康科普品牌,多措并举,从而提高公立医院开展医学科普的能力。

关键词：医学科普必要性运营思路

Investors’ Social Network and Return

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Journal of Social Computing 2022年第3期3卷 231-249页

作者： Yu he Rong lu xiao Han Department of Finance Shanghai University of Finance and EconomicsShanghai 200433China Department of Investment Zhejiang University of Finance and EconomicsHangzhou 310018China School of Information Management&Engineering Shanghai University of Finance and EconomicsShanghai 200433China.

Restricted by the availability of investors’account data,existing studies know little about the reasons for differences in investors’return in financial *** this,this paper,based on the unique account data,reveals that the differences in investors’return are correlated to their locations in the social *** are as follows.(1)Investors’social network constructed based on the submission time of completed orders describes the information diffusion process of financial *** diffuses from the center of the network to the edge,and investors’return depends on their position in the network.(2)Investors’social network affects their return through the positive spillover mechanism of their *** investors are in the center of the social network,the stronger the information sharing,the higher the status in the network,the higher the return;while retail investors are on the edge of the social network,and when their network centrality is certain,they even suffer return penalty for information sharing.(3)The speed of information diffusion in investors’social network has an important impact on asset ***’volatility,return,and liquidity are high in financial markets with an intermediate level of information diffusion *** paper puts forward new reasons for differences in investors’return from the perspective of investors’social network,and holds that big data in the capital market deserve further exploration with the social network method.

关键词： social networks investor networks investors’return asset pricing information diffusion

CO as a therapeutic agent: discovery and delivery forms

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Chinese Journal of Natural Medicines 2020年第4期18卷 284-295页

作者： YANG xiao-xiao KE Bo-Wen lu Wen WANG Bing-he Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State UniversityAtlanta GA 30303USA Department of Anesthesiology West China HospitalChengdu 610000China

Carbon monoxide(CO) as one of the three important endogenously produced signaling molecules, termed as "gasotransmitter," has emerged as a promising therapeutic agent for treating various inflammation and cellular-stress related diseases. In this review, we discussed CO’s evolution from a well-recognized toxic gas to a signaling molecule, and the effort to develop different approaches to deliver it for therapeutic application. We also summarize recently reported chemistry towards different CO delivery forms.

关键词： Carbon monoxide Gasotransmitter CO delivery CO-RMs Organic CO prodrug

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婴幼儿眼性斜颈的临床特征与早期手术效果

国际眼科杂志 2011年第5期11卷 885-887页

作者：项道满陆晓和毛娅妮王建勋周红梅郭峥南方医科大学附属珠江医院眼科中国广东省广州市510280 中国广东省广州市妇女儿童医疗中心眼科 510623

目的:探讨婴幼儿眼性斜颈的临床特征,评估眼性斜颈早期手术效果。方法:对70例患儿进行回顾性分析。通过获取歪头试验、九方位眼球运动检查及眼底照相的结果,分析眼球肌肉异常的类型,对眼性斜颈做出定性诊断。采用计算机辅助斜视诊断技术... 详细信息

目的:探讨婴幼儿眼性斜颈的临床特征,评估眼性斜颈早期手术效果。方法:对70例患儿进行回顾性分析。通过获取歪头试验、九方位眼球运动检查及眼底照相的结果,分析眼球肌肉异常的类型,对眼性斜颈做出定性诊断。采用计算机辅助斜视诊断技术,精确测量出水平斜视度数。对眼性斜颈患者中,上斜肌麻痹、下斜肌功能亢进者,行下斜肌部分切除术。其它原因引起的眼性斜颈,根据眼球肌肉异常类型的不同,设计不同的手术方法。对合并水平斜视者以计算机辅助下斜视测量软件测量出的水平斜视角度为根据,定量设计手术。随访时间6～12mo。结果:本组病例中,均找到眼部病因,以单纯性单眼上斜肌麻痹最常见,54例(77%)。全部患儿均接受手术治疗。一次手术后,单纯性单眼上斜肌麻痹患儿,6mo内治愈或改善者53例(占所有单纯性单眼上斜肌麻痹患儿的98%)。所有患儿6mo内治愈或改善者64例(91%),手术失败者6例。其中3例接受第二次手术,术后3例均治愈或改善。合并水平斜视者11例(16%),一次手术后水平斜视全部矫正。结论:婴幼儿眼性斜颈是一组包含不同类型病因的斜视。明确病因后尽早手术可获得满意头位矫正效果。

关键词：眼性斜颈临床特征婴幼儿计算机辅助斜视

Landslide Damming Threats Along the Jinsha River,China

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Engineering 2024年第11期42卷 326-339页

作者： Shihao xiao Limin Zhang Te xiao Ruochen Jiang Dalei Peng Wenjun lu Xin he Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China The Hong Kong University of Science and Technology Shenzhen–Hong Kong Collaborative Innovation Research Institute Shenzhen 518000China State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection Chengdu University of TechnologyChengdu 610000China

The 2280 km long Jinsha River has been blocked at least four times in the past 30 years.A landslide dam-ming hazard chain can endanger communities and infrastructures hundreds of kilometers downstream from the damming site in alpine *** damming events have resulted in severe consequences,demanding a thorough assessment of damming threats along the entire Jinsha *** study digitizes the Jinsha River and visualizes its topographic,tectonic,hydrologic,and climate characteristics in detail.A two-stage full-probability method is proposed for assessing the damming threats along this river,mak-ing it possible to identify potential damming hotspots and high-priority zones for hazard *** is found that the upper reach of the Jinsha River poses the greatest damming threat,and the threat level gradually decreases *** 33.4%,36.7%,20.5%,and 9.4%of the entire length of the Jinsha River are classified as low,moderate,high,and very high threat levels,*** with existing hydropower projects,future projects in the upper reach are more likely to be exposed to landslide *** highlight the value of basin-scale spatial threat analysis and envisage that our findings will promote more targeted local-scale risk assessments for potential damming *** outcomes provide the basis for managing the risks of river damming and hydropower infras-tructure along the Jinsha River.

关键词： Landslide dam Landslides Jinsha River Risk analysis Hydropower