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The Highest Dam in the World under Construction： The Shuangjiangkou Core-Wall Rockfill Dam

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Engineering 2016年第3期2卷 274-275页

作者： shanping li Bin Duan Professorate Senior Engineer of China Guodian Dadu River Hydropower Development Co. Ltd. Senior Engineer of China Guodian Dadu River Hydropower Development Co. Ltd.

沙漠化是指土地的退化[1–4]。作为一个严重的全球性环境问题,沙漠化已经引起了国际社会的广泛关注。1994年,联合国通过了《联合国防治荒漠化公约》[4]。从那时起,世界各国在防治沙漠化方面做出了不懈的努力[5–12]。然而,沙漠化的蔓延... 详细信息

沙漠化是指土地的退化[1–4]。作为一个严重的全球性环境问题,沙漠化已经引起了国际社会的广泛关注。1994年,联合国通过了《联合国防治荒漠化公约》[4]。从那时起,世界各国在防治沙漠化方面做出了不懈的努力[5–12]。然而,沙漠化的蔓延并没有得到有效的控制,情况甚至变得更糟:它正在以每年50 000~70 000

关键词：心墙堆石坝大坝施工世界江口水电站水库上游大渡河扬子江四川省

Removal of phosphate by Fe-coordinated amino-functionalized 3D mesoporous silicates hybrid materials

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Journal of Environmental Sciences 2011年第2期23卷 199-205页

作者： Jianda Zhang Zhemin Shen Zhijian Mei shanping li Wenhua Wang School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China School of Environmental Science and Engineering Shandong University Jinan 250100 China

Phosphate removal from aqueous waste streams is an important approach to control the eutrophication downstream bodies of water. A Fe（Ⅲ） coordinated amino-functionalized silicate adsorbent for phosphate adsorption was synthesized by a post-grafting and metal cation incorporation process. The surface structure of the adsorbent was characterized by X-ray diffraction, N2 adsoropion/desoprotion technique, and Fourier transform infrared spectroscopy. The experimental results showed that the adsorption equilibrium data were well fitted to the Langmuir equation. The maximum adsorption capacity of the modified silicate material was 51.8 mg/g. The kinetic data from the adsorption of phosphate were fitted to pseudo second-order model. The phosphate adsorption was highly pH dependent and the relatively high removal of phosphate fell within the pH range 3.0-6.0. The coexistence of other anions in solutions has an adverse effect on phosphate adsorption; a decrease in adsorption capacity followed the order of exogenous anions： F^- 〉 SO4^2- 〉 NO3^- 〉 Cl^-. In addition, the adsorbed phosphate could be desorbed by NaOH solutions. This silicate adsorbent with a large adsorption capacity and relatively high selectivity could be utilized for the removal of phosphate from aqueous waste streams or in aquatic environment.

关键词： phosphate mesoporous material Fe coordinated adsorption

Automated Android application permission recommendation

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Science China(Information Sciences) 2017年第9期60卷 132-148页

作者： lingfeng BAO David LO Xin XIA shanping li College of Computer Science and Technology Zhejiang University School of Information Systems Singapore Management University Department of Computer Science University of British Columbia

The number of Android applications has increased rapidly as Android is becoming the dominant platform in the smartphone market. Security and privacy are key factors for an Android application to be successful. Android provides a permission mechanism to ensure security and privacy. This permission mechanism requires that developers declare the sensitive resources required by their applications. On installation or during runtime, users are required to agree with the permission request. However, in practice, there are numerous popular permission misuses, despite Android introducing official documents stating how to use these permissions properly. Some data mining techniques(e.g., association rule mining) have been proposed to help better recommend permissions required by an API. In this paper, based on popular techniques used to build recommendation systems, we propose two novel approaches to improve the effectiveness of the prior work. The first approach utilizes a collaborative filtering technique, which is inspired by the intuition that apps that have similar features — inferred from their APIs — usually share similar permissions. The second approach recommends permissions based on a text mining technique that uses a naive Bayes multinomial classification algorithm to build a prediction model by analyzing descriptions of apps. To evaluate these two approaches, we use 936 Android apps from F-Droid, which is a repository of free and open source Android applications. We find that our proposed approaches yield a significant improvement in terms of precision, recall, F1-score, and MAP of the top-k results over the baseline approach.

关键词： Android permission recommendation association rule collaborative filtering text mining

Exploration and practice of intelligent engineering in Dadu River hydropower construction

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Clean Energy 2020年第3期4卷 288-299页

作者： Bin Duan Yangju Tu shanping li Qinzhi Yan Dadu River Hydropower Development Co. LtdChengdu Sichuan610041China

In view of the difficulties in promoting intelligent management in the field of engineering construction,based on the concept of intelligent enterprise and the actual situation of hydropower project-construction management,this paper puts forward the basic concept,main features and general idea of intelligent engineering.Based on a review of the exploration,pilot construction and comprehensive practice of intelligent engineering in the hydropower construction of Dadu River,the practical results of the intelligent engineering of Dagangshan,Houziyan,Shaping-II and Shuangjiangkou hydropower stations are summarized.The technical system and management model of engineering an early-warning decision centre,intelligent dam project,intelligent underground project,intelligent electromechanical project,intelligent security control,intelligent service guarantee,intelligent environmental and water protection,and intelligent resource control in Shuangjiangkou hydropower station are introduced.It is proposed that intelligent engineering is a high integration of information technology,industrial technology and management technology.And it is pointed out that intelligent engineering will lead in the new development of water conservancy and the hydropower industry,and even the engineering-construction field,throughout the world.

关键词： intelligent engineering Dadu River hydropower construction practice

Software quality assessment model: a systematic mapping study

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Science China(Information Sciences) 2019年第9期62卷 5-22页

作者： Meng YAN Xin XIA Xiaohong ZHANG ling XU Dan YANG shanping li College of Computer Science and Technology Zhejiang University School of Software Engineering Chongqing University Faculty of Information Technology Monash University

Quality model is regarded as a well-accepted approach for assessing, managing and improving software product quality. There are three categories of quality models for software products, i.e., definition model, assessment model, and prediction model. Quality assessment model(QAM) is a metric-based approach to assess the software quality. It is typically regarded as of high importance for its clear method on how to assess a system. However, the current state-of-the-art in QAM research is under limited investigation.To address this gap, the paper provides an organized and synthesized summary of the current QAMs. In detail, we conduct a systematic mapping study(SMS) for structuring the relevant articles. We obtain a total of 716 papers from the five databases, and 31 papers are selected as relevant studies at last. In summary, our work focuses on QAMs from the following aspects: software metrics, quality factors, aggregation methods,evaluation methods and tool support. According to the analysis results, our work discovers five needs that researchers in this area should continue to address:(1) new method and criteria to tailor a quality framework(i.e., structure of software metrics and quality factors) according to different specifics,(2) systematic investigations on the effectiveness, strength and weakness of different aggregation methods to guide the method selection in different context,(3) more investigations on evaluating QAMs in the context of industrial cases,(4) further investigations or real-world case studies on the QAMs related tools, and(5) building a public and diverse software benchmark which can be adopted in different application context.

关键词： software quality systematic mapping study quality assessment model aggregation method

Microstructural evolution and stress relaxation cracking mechanism for Super304H austenitic stainless steel weld metal

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Journal of Materials Science & Technology 2022年第5期100卷 82-90页

作者： Xiaopeng Xiao Dianzhong li Yiyi li shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Insititute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The pre-compressed CT technique was used to quantitatively investigate the formation of stress relaxation cracks under different tensile residual stresses and aging time in Super304H austenitic stainless steel weld metal.The statistical results revealed that intergranular cracks could occur within 2000 h under 650℃ when the residual stress was applied with greater than 18 KN pre-compression force.Detailed grain interior and boundary analyses showed that the growth of intragranular Cu-rich particles could induce a strong grain interior,and the intergranular Nb(C,N)carbides were one of the causes to crack under short-term aging time.For long-term aging time conditions,the intergranular M_(23)C_(6)carbides were more susceptible to crack than intergranular Nb(C,N)carbides.Finally,the mechanism responsible for stress relaxation cracking formation was carefully illustrated for the weld metals after short-term aging and long-term aging,respectively.

关键词： Stress relaxation cracking Super304H steel Weld metal Aging treatment Residual stress Precipitates

安宁疗护分级转诊服务体系的构建及应用效果评价

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中国护理管理 2024年第5期24卷 675-680页

作者：周玉洁袁玲武丽桂李善萍董珊南京中医药大学护理学院南京市210000 南京中医药大学鼓楼临床医学院南京大学医学院附属鼓楼医院

目的:构建安宁疗护分级转诊服务体系并评价其应用效果,为临床进行系统、规范的安宁疗护患者分级转诊提供参考。方法:通过文献研究、主题分析、德尔菲专家函询法形成安宁疗护分级转诊服务体系。采用类实验研究法,随机抽取南京市参与安宁... 详细信息

目的:构建安宁疗护分级转诊服务体系并评价其应用效果,为临床进行系统、规范的安宁疗护患者分级转诊提供参考。方法:通过文献研究、主题分析、德尔菲专家函询法形成安宁疗护分级转诊服务体系。采用类实验研究法,随机抽取南京市参与安宁疗护分级转诊服务的医疗机构中的80名患者,进行体系运行前后的向上转诊率、向下转诊率、患者家属对转诊服务满意度及患者死亡质量的调查与统计分析。结果:2轮专家函询的专家积极系数均为100.0%;专家权威系数为0.800和0.825;肯德尔协调系数分别为0.141和0.632(P<0.01);最终确定安宁疗护分级转诊服务体系包括一级指标4项(各级医疗机构开展安宁疗护标准、患者转诊标准、信息共享机制、质量控制指标)、二级指标14项、三级指标70项。且安宁疗护分级转诊服务体系提高了向下转诊率、降低了向上转诊率、提高了死亡质量(P<0.05)。结论:安宁疗护分级转诊服务体系具有科学性、可靠性、专科性和实用性,能为临床更好地开展安宁疗护患者分级转诊提供参考。

关键词：安宁疗护分级转诊服务体系德尔菲专家函询法

Precipitation Behavior and Mechanical Properties of a 16Cr-25Ni Superaustenitic Stainless Steel Weld Metal During Post-weld Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 577-590页

作者： Wenbin Tian Dong Wu Yiyi li shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

A 16Cr-25Ni superaustenitic stainless steel weld metal for austenitic stainless steel/ferrite heat-resistance steel dissimilar metal weld was designed and prepared through tungsten inert-gas welding.The precipitate evolution and its correlation with mechanical properties were investigated during post-weld heat treatment(PWHT)at 690℃ for up to 12 h.The primary precipitates in the as-welded weld metal were identified as Mo-rich M6C carbides in the interdendritic region and semicontinuous fine-sized M23C6 carbides along grain boundary.After PWHT,three types of precipitates coexisted in the interdendritic region:primary M6C carbides,newly precipitated Mo-rich M2X carbonitrides and some of the secondary M23C6 carbides.Additionally,mass secondary M23C6 carbides formed and coarsened along grain boundary.No undesirable intermetallic phases formed during the whole period.The M2X and interdendritic M23C6 improved the strength of the weld metal after PWHT,but the elongation and impact toughness degraded,which were mainly owing to the intergranular M23C6 carbides that changed the fracture mode from ductile transgranular mode to mixed mode of transgranular and intergranular fracture.Meanwhile,the coarsening of M2X carbonitrides may lead to the elongation loss during 8 h to 12 h.Evolution of impact toughness was also related to the M2X carbonitrides,which made the crack easier to propagate compared with austenitic matrix and contributed to the decline of impact toughness.However,due to the sluggish precipitation of M2X carbonitrides with longer holding time,the decreasing trend became slow from 4 to 12 h.The results showed that PWHT should be controlled within 8 h to obtain better combination of strength and ductility.

关键词： Superaustenitic stainless steel Weld metal Post-weld heat treatment Precipitate evolution Mechanical properties

Effects of Stabilization Heat Treatment on Microstructure and Mechanical Properties of Si‑Bearing 15Cr–9Ni–Nb Austenitic Stainless Steel Weld Metal

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 637-649页

作者： Yakui Chen Dong Wu Dianzhong li Yiyi li shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Two 15Cr–9Ni–Nb austenitic stainless steel weld metals with 2.5%Si and 3.5%Si(namely 2.5Si and 3.5Si samples,respectively)were designed and prepared through tungsten inert gas(TIG)welding and then hold at 800℃ or 900℃ for 3 h for stabilization.The microstructure and mechanical properties were investigated both for the as-welded and after-stabilization heat treatment(SHT)weld metals.There are 3.0–4.0%martensite and 2.5–3.5%δferrite in the 2.5Si as-welded weld metal and 6.0–7.0%δferrite in the 3.5Si as-welded weld metal.After SHT,a large amount of martensite formed in the 2.5Si weld metal,andδ→γtransition occurred during the SHT process both for the 2.5Si and 3.5Si weld metals.There were a large amount of coarse NbC and few nanoscale NbC in the as-welded weld metal.During the SHT,a large amount of nanoscale NbC formed in the matrix,while a large number of G phases formed at the austenite grain boundaries and theδ/γinterfaces.The decrease in solid solution C andδferrite content led to the decline of the yield strength of the weld metal after SHT.The martensite formed in 2.5Si weld metal after SHT had less effect on strength because of its low carbon content.The G phases formed during the SHT reduced the impact energy of the weld metal because it promoted the intergranular fracture,while theδ→γtransition reduced the amount of theδ/γinterfaces and avoided the intergranular fracture,which was beneficial for the impact toughness of the weld metals.

关键词： Austenitic stainless steel Weld metal Stabilization heat treatment Martensite NbC δ→γtransition