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Journal of Hydrodynamics 2007年第5期19卷 613-622页

作者： hu zhi-gen FAN Xi-e huAI Wen-xin LIU Quan Zhu Ming-xing State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan University Wuhan 430072 China China Gezhouba （Group） Corporation Yichang 443002 China

The protection of downstream concrete slab is a key issue for the stability of overflow earth-rock cofferdam. The coupling effect between bedding layer and concrete slab was taken into account when the stability of downstream concrete slab was researched. The characteristics of overflow and seepage over the downstream concrete slab were investigated when floodwater passes over the cofferdam. Firstly a limit equation of seepage failure for the bedding layer was derived with the consideration of geometric and mechanical factors, and a reliability model was established and numerically simulated. Then based on the reliability calculation for the bedding layer, the coupling effect between bedding layer and downstream concrete slab was analyzed. Under the most unfavorable pressure condition for the concrete slab, its instability criterion was put forward, which offers a structural design tool of downstream concrete slab for overflow earth-rock cofferdam. Compared with model tests, it shows that the model of reliability calculation of bedding layer and the stability analysis of downstream concrete slab are effective.

关键词： overflow earth-rock cofferdam couplingeffect reliability calculation stability analysis Monte Carlomethod

土石过水围堰条件下的水电工程施工进度风险研究

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系统工程理论与实践 2013年第6期33卷 1622-1627页

作者：陈述胡志根武汉大学水资源与水电工程科学国家重点实验室武汉430072

土石过水围堰条件下的水电工程施工,受基坑淹没和基坑恢复时间的随机性影响,工序历时估计、有效施工天数和规定完工日期等因素具有不确定性、使其施工进度延误无法预知.基于施工进度风险的这种占线特性,分析水电工程施工进度风险因素,... 详细信息

土石过水围堰条件下的水电工程施工,受基坑淹没和基坑恢复时间的随机性影响,工序历时估计、有效施工天数和规定完工日期等因素具有不确定性、使其施工进度延误无法预知.基于施工进度风险的这种占线特性,分析水电工程施工进度风险因素,建立占线进度风险模型,计算占线策略的竞争比.依据一般占线策略与离线最优策略的关系,引入风险补偿模型,根据决策人不同的风险容忍度和未来预期,优化风险补偿策略,为水电工程的施工进度决策提供了理论支持.

关键词：土石过水围堰施工进度占线特征风险补偿

Robotic versus laparoscopic surgery for sporadic benign insulinoma:Short-and long-term outcomes

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 399-405页

作者： Zhu-Zeng Yin Yuan-Xing Gao zhi-Ming Zhao Ming-gen hu Wen-Bo Tang Rong Liu Faculty of Hepato-Pancreato-Biliary Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China Institute of Hepatobiliary Surgery of Chinese PLA Beijing 100853China Key Laboratory of Digital Hepatobiliary Surgery of Chinese PLA Beijing 100853China

Background:Minimally invasive surgery is the optimal treatment for *** present study aimed to compare short-and long-term outcomes of laparoscopic and robotic surgery for sporadic benign ***:A retrospective analysis of patients who underwent laparoscopic or robotic surgery for insulinoma at our center between September 2007 and December 2019 was *** demographic,perioperative and postoperative follow-up results were compared between the laparoscopic and robotic ***:A total of 85 patients were enrolled,including 36 with laparoscopic approach and 49 with robotic *** was the preferred surgical ***-nine patients(69.4%)underwent enucleation;among them,26 and 33 patients underwent laparoscopic and robotic surgery,*** enucleation had a lower conversion rate to laparotomy(0 vs.19.2%,P=0.013),shorter operative time(102.0 vs.145.5 min,P=0.008)and shorter postoperative hospital stay(6.0 vs.8.5 d,P=0.002)than laparoscopic *** were no differences between the groups in terms of intraoperative blood loss,the rates of postoperative pancreatic fistula and *** a median follow-up of 65 months,two patients in the laparoscopic group developed a functional recurrence and none of the patients in the robotic group had a ***:Robotic enucleation can reduce the conversion rate to laparotomy and shorten operative time,which might lead to a reduction in postoperative hospital stay.

关键词： Robotic surgical procedures Laparoscopy Insulinoma Enucleation Pancreatectomy

基于上-下游水电站协商定权的施工导流方案决策模型

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四川大学学报（工程科学版） 2014年第1期46卷 68-74页

作者：张超胡志根中国水电顾问集团成都勘测设计研究院四川成都610072 武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

基于上游水电站控泄的施工导流方案决策具有多目标性和双边冲突性特点,提出了将上游水电站汛限水位和下游水电工程施工导流标准的组合作为施工导流方案可行集,在建立方案综合评价指标体系的基础上,考虑水文、水力不确定性,利用Monte-Ca... 详细信息

基于上游水电站控泄的施工导流方案决策具有多目标性和双边冲突性特点,提出了将上游水电站汛限水位和下游水电工程施工导流标准的组合作为施工导流方案可行集,在建立方案综合评价指标体系的基础上,考虑水文、水力不确定性,利用Monte-Carlo方法估算各风险效益指标值。基于协商定权理论,将指标权重的分配作为决策过程中上-下游水电站之间冲突和争议的焦点,构筑冲突双方的协商定权局势,并将熵权引入到损失函数计算模型的构建中。工程实例分析表明,模型和方法是可行的、有效的,协商后的指标权重分配更加均衡与全面,反映了双方冲突的协调与解决,决策结果可靠,为上游水电站控泄条件下施工导流方案优选与风险调控提供了新的思路和方法。

关键词：施工导流方案协商定权控泄汛限水位冲突熵权

时变条件下高堆石坝施工度汛协商决策的演化分析模型

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水利学报 2013年第11期44卷 1359-1365页

作者：刘潋胡志根武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

大坝施工度汛方案的选择与坝体填筑进度的计划及控制密切相关。本文针对高堆石坝填筑施工过程的挡水和过水的特点,以坝前水位的随机性和坝体挡水高程的时变性描述施工度汛风险。结合协商者的风险偏好和利益导向,引入承包商与业主在不同... 详细信息

大坝施工度汛方案的选择与坝体填筑进度的计划及控制密切相关。本文针对高堆石坝填筑施工过程的挡水和过水的特点,以坝前水位的随机性和坝体挡水高程的时变性描述施工度汛风险。结合协商者的风险偏好和利益导向,引入承包商与业主在不同度汛方案下的效益函数,运用微分对策建立时变条件下高堆石坝施工度汛协商决策演化模型,给出了协商机制下度汛决策行为的动态演化过程及其决策路径和坝体填筑高程的变化特征。实例计算结果表明决策演化模型下的坝体填筑上升高度与实际工程接近,工期与实际工程相符,验证了该模型的可行性与有效性,对高堆石坝度汛风险决策与控制具有理论意义和参考价值。

关键词：高堆石坝施工度汛协商决策演化微分对策

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

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Rare Metals 2024年第4期43卷 1828-1835页

作者： gen Jin Fang-Fang Xu Xun-Xun hu Yue Xu School of Chemistry Beihang UniversityBeijing100191China Guobiao(Beijing)Testing and Certification Co. LtdBeijing100088China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt *** this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically *** results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound *** mechanism for the formation of compound layer as well as the growth kinetics of the layer was also *** the duplex treatment,the wear and corrosion resistances of steel surface were significantly *** was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·moL^(-1).

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

Tetraethylenepentamine-functionalized magnetic mesoporous composites as a novel adsorbent for the removal Cr(Ⅲ)-ethylenediaminetetraacetic acid in complex solution

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Chinese Journal of Chemical Engineering 2024年第4期68卷 16-26页

作者： zhi hu Jiahong Wang Tongtong Sun School of Environmental Science and Engineering Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Green Preparation and Functionalization of Inorganic Materials Xi'an 710021China

A novel tetraethylenepentamine(TEPA) functionalized magnetic mesoporous silica adsorbent(FNMs/TEPA) was prepared for the adsorption of Cr(Ⅲ)-ethylenediaminetetraacetic acid(EDTA)from wastewater. The characterization of the prepared adsorbent certified that TEPA was modified onto the magnetic mesoporous silicon(FNMs), while FNMs/TEPA maintained the ordered mesoporous and pristine magnetic properties. The batch adsorption experiments demonstrated that TEPA significantly enhanced the removal capacity of the adsorbent for Cr(Ⅲ)-EDTA. FNMs/TEPA exhibited an excellent adsorption property(13.84 mg·g-1) at p H 4.0. Even in the presence of high concentrations of coexisting ions and organic acids, the adsorption performance of FNMs/TEPA was stable. Experimental characterization and DFT demonstrated that the adsorption of Cr(Ⅲ)-EDTA was ascribed to the electrostatic interaction, hydrogen bonding, and complexation between Cr(Ⅲ)-EDTA and amino groups on the adsorbent surface. The analysis of the independent gradient model(IGM) shows that electrostatic interaction is the main mode of action in the adsorption process. Moreover, FNMs/TEPA demonstrated remarkable reusability in three regeneration cycles. These findings indicated that FNMs/TEPA possessed excellent application prospects in the disposal of wastewater containing Cr(Ⅲ)-EDTA.

关键词： TEPA functionalized magnetic mesoporous silicon Adsorption Cr(III)-EDTA Density functional theory calculations

基于决策者风险偏好的混凝土坝浇筑方案灰靶评价模型

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四川大学学报（工程科学版） 2013年第4期45卷 21-26页

作者：卞小草胡志根武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

混凝土坝浇筑方案优选是一个在不确定环境下的多属性决策问题,评价指标具有模糊性和灰色关联的特点。为了增强指标权重的客观性和可信度,引入前景价值函数来描述决策者的风险态度,构建改进后的灰靶评价模型。分别以理想解最优方案点和... 详细信息

混凝土坝浇筑方案优选是一个在不确定环境下的多属性决策问题,评价指标具有模糊性和灰色关联的特点。为了增强指标权重的客观性和可信度,引入前景价值函数来描述决策者的风险态度,构建改进后的灰靶评价模型。分别以理想解最优方案点和理想解最劣方案点代表正、负靶心作为参考点,构造正、负标准模式对指标特征值进行灰靶变换,计算靶心系数和价值矩阵,根据综合前景价值最大化求解指标权重。最后结合工程实例,按照综合前景价值实现对各浇筑方案的排序,验证了方法的可行性和有效性。

关键词：混凝土施工方案优选前景理论灰靶理论多属性决策

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梯级施工导流系统整体风险分析

水科学进展 2012年第3期23卷 396-402页

作者：张超胡志根刘全武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

进行流域梯级水电站开发,对相邻两座同期建设的水电工程组成的梯级施工导流系统进行整体风险分析意义重大。基于风险分析理论,考虑梯级施工导流系统水文和水力的不确定性,建立了系统整体风险数学模型。在此基础上构建了不同洪水组合情... 详细信息

进行流域梯级水电站开发,对相邻两座同期建设的水电工程组成的梯级施工导流系统进行整体风险分析意义重大。基于风险分析理论,考虑梯级施工导流系统水文和水力的不确定性,建立了系统整体风险数学模型。在此基础上构建了不同洪水组合情况下的风险计算模型,并利用Monte-Carlo方法耦合主要风险因素进行模型求解。同时,针对洪水过程遭遇情况下的风险模型,通过引入起始时间差随机因素来计算下游导流系统施工洪水过程。工程实例分析证明,风险分析模型和方法是可靠、有效的,为流域梯级开发条件下施工导流标准选取及导流方案优选提供重要依据。

关键词：梯级施工导流系统风险分析 Monte—Carlo方法洪水组合

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施工导流方案多属性群协商决策

系统工程理论与实践 2014年第5期34卷 1324-1329页

作者：薛进平胡志根刘全武汉大学水资源与水电工程科学国家重点实验室武汉430072

针对异质群体参与的施工导流方案风险型多属性决策问题,分析导流方案决策主体面临不同属性时所对应的偏好尺度和评价效用的差异性,引入群体协商集结理论,提出基于可能度矩阵表征的导流方案群决策策略.通过对各属性下导流方案决策主体的... 详细信息

针对异质群体参与的施工导流方案风险型多属性决策问题,分析导流方案决策主体面临不同属性时所对应的偏好尺度和评价效用的差异性,引入群体协商集结理论,提出基于可能度矩阵表征的导流方案群决策策略.通过对各属性下导流方案决策主体的非一致性、模糊性意见进行协商集结,计算属性权重的协商区间.基于蒙特卡罗模拟仿真技术,计算随机权重向量下导流方案两两间的优胜概率,得到描述导流方案优胜程度的模糊互补判断矩阵,据此进行备选方案的优先排序,并给出了排序的可信度.实例验证了该方法的可行性和有效性.研究为多属性群决策视角下导流方案的优选提供了理论基础和决策支持.

关键词：施工导流群决策协商异质群体蒙特卡罗属性