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北京市岩溶地下水质量评价及其生态环境效应

中国地质 2024年第4期51卷 1266-1279页

作者：郭高轩代垠东许亮朱琳戚琦欧志亮沈媛媛北京市地质环境监测所北京100195 城市地下水安全防控技术创新基地北京100195 首都师范大学水资源安全北京实验室北京100048

【研究目的】岩溶地下水是北京市重要的供水水源,在城市供水安全保障中发挥着难以替代的作用,同时又具有重要的生态功能。【研究方法】本文以2021年6月在北京市系统采集的278件岩溶地下水样化验数据为基础,以岩溶水系统为单元,开展了岩... 详细信息

【研究目的】岩溶地下水是北京市重要的供水水源,在城市供水安全保障中发挥着难以替代的作用,同时又具有重要的生态功能。【研究方法】本文以2021年6月在北京市系统采集的278件岩溶地下水样化验数据为基础,以岩溶水系统为单元,开展了岩溶水单因子质量评价和综合质量评价,并首次对有机指标进行了统计和分析。【研究结果】(1)北京市岩溶水的pH、TDS和TH平均值分别为7.69、334.77 mg/L和262.01 mg/L,具有弱碱性、低盐度和低硬度的特点,地下水质量总体良好。(2)非常规指标的检出率从大到小为:苯并[a]芘(4.32%)、三溴甲烷(3.60%)和二甲苯(总量)(2.52%),应当引起足够重视。(3)北京市岩溶水水质Ⅰ~Ⅲ类总占比为82.01%,Ⅳ和Ⅴ类总占比为17.99%,超标点主要集中在山区与平原分界线处,超标指标主要有Fe、TH、NH_(3)-N、Mn、SO_(4)^(2-)、F^(-)、NO_(3)-N等。【结论】北京市生态涵养区是重要的水源补给区和生态保护区,区内岩溶水对于保障首都供水安全和保护生态环境具有重要意义,今后应通过提高植被覆盖率加强水源涵养以增加补给量,应严格控制点源和面源污染减少污染物输入,持续优化监测网络进行预警,广泛宣传增强公众生态环保意识,共同保护岩溶水的生态环境。

关键词：岩溶水系统单因子质量评价综合质量评价水化学特征生态环境水文地质调查工程北京市

Novel Ship Propulsion System

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 198-206页

作者： JI Yulong SUN Yuqing ZHANG Hongpeng ZHANG yindong CHEN Haiquan School of Marine Engineering Dalian Maritime University Dalian 116026 China

As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion （IHP）, is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion （DP） ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.

关键词： ship integrated hydraulic propulsion (IHP) ship propulsion system modeling and simulation working condition matching characteristic

Approximating probability distribution of circuit performance function for parametric yield estimation using transferable belief model

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Science China(Information Sciences) 2013年第11期56卷 106-124页

作者： XU XiaoBin ZHOU DongHua JI yindong WEN ChengLin School of Automation and Institute of Systems Science and Control Engineering Hangzhou Dianzi University Department of Automation and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Research Institute of Information Technology (RIIT) Tsinghua University

This paper applies the transferable belief model(TBM)interpretation of the Dempster-Shafer theory of evidence to approximate distribution of circuit performance function for parametric yield *** input parameters of performance function as credal variables defned on a continuous frame of real numbers,the suggested approach constructs a random set-type evidence for these *** corresponding random set of the function output is obtained by extension principle of random *** the TBM framework,the random set of the function output in the credal state can be transformed to a pignistic state where it is represented by the pignistic cumulative *** an approximation to the actual cumulative distribution,it can be used to estimate yield according to circuit response *** advantage of the proposed method over Monte Carlo(MC)methods lies in its ability to implement just once simulation process to obtain an available approximate value of yield which has a deterministic estimation *** the same error,the new method needs less number of calculations than MC methods.A track circuit of high-speed railway and a numerical eight-dimensional quadratic function examples are included to demonstrate the efciency of this technique.

关键词： Dempster-Shafer theory of evidence Monte Carlo methods parametric yield random set transferable belief model

Robust Electric Vehicle Routing Problem with Time Windows under Demand Uncertainty and Weight-Related Energy Consumption

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Complex System Modeling and Simulation 2022年第1期2卷 18-34页

作者： yindong Shen Leqin Yu Jingpeng Li Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China Division of Computer Science and Mathematics University of StirlingStirlingFK94LAUK

Vehicle routing problem with time windows(VRPTW)is a core combinatorial optimization problem in distribution *** electric vehicle routing problem with time windows under demand uncertainty and weight-related energy consumption is an extension of the *** some researchers have studied either the electric VRPTW with nonlinear energy consumption model or the impact of the uncertain customer demand on the conventional vehicles,the literature on the integration of uncertain demand and energy consumption of electric vehicles is still ***,practically,it is usually not feasible to ignore the uncertainty of customer demand and the weight-related energy consumption of electronic vehicles(EVs)in actual ***,we propose the robust optimization model based on a route-related uncertain set to tackle this ***,adaptive large neighbourhood search heuristic has been developed to solve the problem due to the NP-hard nature of the *** effectiveness of the method is verified by experiments,and the influence of uncertain demand and uncertain parameters on the solution is further explored.

关键词： electric vehicle routing problem time windows uncertain demand energy consumption model robust optimization adaptive large neighbourhood search

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某型电点火具静电感度发火研究

新技术新工艺 2021年第5期401卷 42-45页

作者：李便花郝雁军潘会平郭健杨银栋周文伟陈丽娟山西北方晋东化工有限公司山西阳泉045000 驻太原地区第三军事代表室山西太原030000

国际形势瞬息万变,技术创新不断涌现,现有复杂的电磁环境对武器装备的抗干扰性要求越来越高,静电的认识及产品防静电的要求也越来越严格。电火工品是弹药中感度最高、最危险的部分,作为武器的核心首发元件,其安全性及可行性至关重要。... 详细信息

国际形势瞬息万变,技术创新不断涌现,现有复杂的电磁环境对武器装备的抗干扰性要求越来越高,静电的认识及产品防静电的要求也越来越严格。电火工品是弹药中感度最高、最危险的部分,作为武器的核心首发元件,其安全性及可行性至关重要。以案例为切入点,从产品结构设计、生产工艺等方面进行系统分析及试验验证,确定了产品防静电结构的设计改进方案,在不改变总体结构的情况下,调整绝缘套管材料及尺寸,能够满足产品设计及生产要求。研究结果可为防静电设计“堵”的模式提供参考。

关键词：电点火具静电感度发火火工品

A Discrete Artificial Bee Colony Algorithm for Stochastic Vehicle Scheduling

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Complex System Modeling and Simulation 2022年第3期2卷 238-252页

作者： Yuanyuan Li yindong Shen Jingpeng Li Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China Division of Computer Science and Mathematics University of StirlingStirlingFK94LAUK

Vehicle scheduling plays a profound role in public ***,stochastic vehicle scheduling may lead to more robust *** solve the stochastic vehicle scheduling problem(SVSP),a discrete artificial bee colony algorithm(DABC)is *** to the discreteness of SVSP,in DABC,a new encoding and decoding scheme with small dimensions is designed,whilst an initialization rule and three neighborhood search schemes(i.e.,discrete scheme,heuristic scheme,and learnable scheme)are devised individually.A series of experiments demonstrate that the proposed DABC with any neighborhood search scheme is able to produce better schedules than the benchmark results and DABC with the heuristic scheme performs the best among the three proposed search schemes.

关键词： public transportation stochastic vehicle scheduling discrete artificial bee colony search scheme

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相干喇曼诱导甲烷V-T弛豫过程

光学学报 1988年第8期 700-704页

作者：王乃光郑殷东杨石军吴存恺夏宇兴中国科学院安徽光学精密机械研究所中国科学技术大学激光光谱实验室

本文首次报道了用相干喇曼激光诱导红外荧光的方法,研究多原子分于-OH4的振动能转移过程,并测出v4振动能级到平动能转移速率常数为:KVL=（8±）×10-5.

关键词：相干喇曼诱导红外荧光振动能量转移振动能量弛豫甲烷

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车载通信终端防浪涌电路的优化设计

汽车电器 2024年第7期 63-64页

作者：常君叶丹王寅东肖剑阁大连东软智行科技有限公司辽宁大连116085

文章针对车载(尤其是新能源汽车)通信终端在使用时出现的偶发浪涌破坏问题,分析浪涌产生的不确定性,通过排查和试验复现失效过程,锁定问题,并提出三级防护的优化解决方案。试验结果表明,该方案能够提高车载通信终端抗扰能力,以达到IEC 6... 详细信息

文章针对车载(尤其是新能源汽车)通信终端在使用时出现的偶发浪涌破坏问题,分析浪涌产生的不确定性,通过排查和试验复现失效过程,锁定问题,并提出三级防护的优化解决方案。试验结果表明,该方案能够提高车载通信终端抗扰能力,以达到IEC 61000-4-5试验标准要求,同时也达到实用性目的。

关键词：新能源电磁兼容屏蔽

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Robust photocatalytic hydrogen production on metal-organic layers of Al-TCPP with ultrahigh turnover numbers

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Chinese Chemical Letters 2021年第12期32卷 3833-3836页

作者： Hui Yu Xiang Wu Qiaoqiao Mu Zhihe Wei yindong Gu Xuzhou Yuan Yongtao Lu Zhao Deng yang Peng Soochow Institute for Energy and Materials Innovations College of EnergySoochow UniversitySuzhou 215006China Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Soochow UniversitySuzhou 215006China

The development of robust photocatalytic systems is key to harvest the solar power for hydrogen production. In the current study, a series of aluminum-based porphyrinic metal organic frameworks (AlTCPP) with various morphologies of bulk, carambola-like and nanosheets are synthesized with modulated layer thickness. Morphology-dependent photocatalytic activities in hydrogen production are witnessed and inversely correlate to the thickness of the Al-TCPP micro-platelets or nanosheets. Particularly, the exfoliated metal organic layers (MOLs) of Al-TCPP demonstrated a high hydrogen yield rate of 1.32×10^(4)μmol h^(-1)g^(-1)that is 21-fold of that from the bulk catalyst, as well as an exceptional TON of6704 that seldom seen in literature. Through comprehensive photochemical characterizations, the remarkable photocatalytic performance of Al-TCPP-MOL is attributed to the great charge separation efficiency and transfer kinetics endowed by the ultrathin 2D morphology with extended active surface area.

关键词： Photocatalysis Metal organic layers Al-TCPP Hydrogen production Turnover numbers