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汉江流域生态综合网络构建与生态安全格局识别研究

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长江流域资源与环境 2024年第2期33卷 362-373页

作者：朱炳臣李同昇陈谢扬李炬霖西北大学城市与环境学院陕西西安710127 西北大学陕西省情研究院陕西西安710127

汉江流域生态环境优越、自然资源丰富,是“南水北调”的重要水源区,也是连接我国中西部地区社会经济发展的重要纽带,近年来水土流失加剧,洪涝灾害频发,已影响流域社会经济可持续发展,生态安全格局科学构建有利于生态系统保护和生态风险... 详细信息

汉江流域生态环境优越、自然资源丰富,是“南水北调”的重要水源区,也是连接我国中西部地区社会经济发展的重要纽带,近年来水土流失加剧,洪涝灾害频发,已影响流域社会经济可持续发展,生态安全格局科学构建有利于生态系统保护和生态风险防控。基于景观生态学“斑块—廊道—基质”理论,分别从生态系统服务和生态风险两方面构建汉江流域生态综合网络,通过分析网络要素结构识别生态安全格局。研究发现:(1)流域生态系统调节功能极重要区占流域总面积的25.71%,主要集中在秦巴山地和汉江流域下游地区;生态极敏感区占流域总面积的9.18%,零星分布在汉江谷地、南阳盆地和江汉平原。(2)通过生态网络识别出生态源19个、生态廊道34条、生态保护节点14处,呈现出“大分散、小聚集”的格局;通过生态风险网络识别出风险源22个、生态风险廊道43条、生态修复节点15处,呈现出“大分散”的格局。(3)汉江流域呈现出“西高东低、南高北低”的生态安全格局,保护斑块、保护廊道和保护节点多位于秦巴山地;修复斑块、修复廊道和修复节点多集中在汉江谷地和流域中下游地区;保护与修复节点多位于汉江流域上游地区。(4)秦巴山地承担着保障流域中下游地区生态安全的功能,需要构建山地生态安全屏障;河流水系是生态风险网络中胁迫因子扩散的主要廊道,流域生态保护与修复亟待重视。构建的生态风险网络可进一步完善流域生态安全格局识别方法,并为汉江流域生态环境改善和国土空间高效利用提供参考依据。

关键词：生态系统调节功能生态敏感性生态综合网络生态安全格局汉江流域

基于上下游市场联动的燃煤电厂两阶段决策模型

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中国电机工程学报 2024年第8期44卷 3036-3045,I0008页

作者：廖志伟郑广昱谢汛恺王博文张文锦华南理工大学电力学院广东省广州市510640

随着大宗能源价格大幅波动及新能源上网冲击,作为现阶段不可或缺的燃煤电厂经营举步艰难。对上游燃料采购及仓储成本进行优化管控的同时,对下游电力市场竞价上网进行联动决策,可在一定程度上提高双碳背景下火力发电企业的生存空间。针... 详细信息

随着大宗能源价格大幅波动及新能源上网冲击,作为现阶段不可或缺的燃煤电厂经营举步艰难。对上游燃料采购及仓储成本进行优化管控的同时,对下游电力市场竞价上网进行联动决策,可在一定程度上提高双碳背景下火力发电企业的生存空间。针对上下游市场联动决策周期不一致以及固定发电成本二次曲线无法反映发电成本变动的问题,提出一种基于上下游市场联动的购煤与竞价燃煤电厂两阶段优化决策模型。首先提出燃煤电厂上下游市场的联动模型;其次建立购煤与竞价策略两阶段决策模型,并讨论条件风险价值对决策的影响;最后以燃煤电厂A进行算例分析和两阶段决策模型的有效性验证。算例结果表明,所提两阶段决策模型可以解决上述问题,实现利润最大化。

关键词：电煤市场日前电力市场条件风险价值滚动优化两阶段决策

维普期刊数据库博看期刊

重金属污染与生态风险评价——基于自组织地图和正矩阵分解的临澧县土壤研究

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Journal of Central South University 2024年第4期31卷 1371-1382页

作者：邹昊李武清任伯帜谢青蔡昭奇陈禄源王瑾 School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China Institute of Geological Survey of Hunan Province Changsha 410083China School of Resource Security Hunan University of Science and TechnologyXiangtan 411201China School of Earth Science and Spatial Information Hunan University of Science and TechnologyXiangtan 411201China College of Foreign Languages Hunan UniversityChangsha 410082China

土壤重金属污染一直是环境科学中备受关注的问题。本文对中国临澧县土壤中六种重金属(As、Cd、Cr、Cu、Zn和Pb)的污染水平、分布、来源及其对生态环境的影响进行了分析。样本浓度分析结果显示Cd的浓度均超过背景值,超标率达到100%,其余... 详细信息

土壤重金属污染一直是环境科学中备受关注的问题。本文对中国临澧县土壤中六种重金属(As、Cd、Cr、Cu、Zn和Pb)的污染水平、分布、来源及其对生态环境的影响进行了分析。样本浓度分析结果显示Cd的浓度均超过背景值,超标率达到100%,其余元素的平均浓度与背景值相近,超标率均在13.5%以下。地累计指数和富集因子指数均显示Cd是污染最严重的元素,其他元素则处于轻度污染级别以下。自组织地图(SOM)和正矩阵分解(PMF)的分析结果显示农业活动是土壤中重金属元素主要来源之一,而自然风化和工业污染也会导致土壤污染。Cd是临澧县土壤中污染最显著的元素,对生态环境造成的影响最大,达到较高风险等级。本研究为降低土壤重金属污染和生态环境风险提供了重要参考,同时也为相关部门制定有效的污染防治、生态环境保护政策提供了理论指导。

关键词：生态风险正矩阵分解重金属污染土壤自组织地图

Functional knowledge integration of the design process

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Science China(Technological Sciences) 2017年第2期60卷 209-218页

作者： CHEN Bin xie YouBai State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China

Functional knowledge integration is the initial and core phase of a design process. It is the key phase to ensure that the functional requirement of the design product can be appropriately complied with, and its result is also the rudiment of the subsequent detailed design work. If this important phase can be supported by an increasingly distributed resource environment, and be automated such that its completion requires less manual work, the efficiency of the design process would be largely improved and its ability to promote innovation would be enhanced. Therefore, this study involved a detailed analysis of the functional knowledge integration of the design process, as well as the proposal of a corresponding running model. Based on the model, a computational algorithm and an evaluating method were established to automate functional knowledge integration. A corresponding computer program was developed to prove the feasibility of this approach, and it was used to design a solarpowered wiper blade.

关键词： functional knowledge integration design process running model computational algorithm evaluating method

A NEW APPROACH TO MODEL FINANCIAL MARKETS

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Journal of Systems Science & Complexity 2013年第3期26卷 432-440页

作者： xie Haibin WANG Shouyang Research Center of Applied Finance University of International Business and Economics Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper deals with the problem of how to take full use of prices information to model financial markets.A range decomposition technique is proposed to decompose the returns into two *** is proved theoretically that these two components are bi-directional Granger causality,which makes it convenient to establish a vector autoregressive model(VAR).Both simulations and empirical studies are performed,and the results are consistent with the theoretical *** range decomposition approach presented in this paper is more efficient in information employment and suggests a new framework to model financial markets.

关键词： Granger causality range range decomposition VAR.

深水峡谷上游复合浊积砂岩储层类型及其展布规律——以琼东南盆地中央峡谷陵水气田为例

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石油与天然气地质 2024年第2期45卷 516-529页

作者：付超谢玉洪赵雨初王晖苑志旺徐伟陈国宁中海油研究总院有限责任公司北京100028 中海油有限责任公司北京100010 东南大学仪器科学与工程学院江苏南京211189

琼东南盆地陵水气田位于中央峡谷上游,以浊积砂岩储层为主,受沉积和成岩作用共同影响,储层类型较为多样,表征难度较大。为了预测深水甜点区分布,依据峡谷形态和埋深规律,将峡谷上游区域沿浊流流向依次划分为调整段、顺直段和弯曲段;通... 详细信息

琼东南盆地陵水气田位于中央峡谷上游,以浊积砂岩储层为主,受沉积和成岩作用共同影响,储层类型较为多样,表征难度较大。为了预测深水甜点区分布,依据峡谷形态和埋深规律,将峡谷上游区域沿浊流流向依次划分为调整段、顺直段和弯曲段;通过综合井筒中粒度、孔喉结构和填隙物类型对储层进行分类;基于岩石组构和物性参数间定量关系,分析对应沉积储层的沉积成因。研究认为,峡谷调整段以粗粒重力流沉积为主,随着颗粒间杂基含量降低,储层物性向下游逐渐变好;顺直段以细-粉砂浊流沉积为主,储层质量较为稳定,仅在局部因Ca^(2+)离子富集致使胶结作用增强;弯曲段以粉砂质浊流堆积为主,较细的沉积粒度致使储层质量向下游方向随着埋深的增加而逐渐变差。调整段沉积过程控制储层质量,顺直段-弯曲段成岩作用控制储层质量。

关键词：中央峡谷汇聚区构型级次物性展布浊积砂体琼东南盆地

Effect of seismic super-shear rupture on the directivity of ground motion acceleration

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 519-527页

作者： Hu Jinjun xie Lili Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration School of Civil Engineering and Architecture Harbin Institute of Technology

The effect of seismic super-shear rupture on the directivity of ground motions using simulated accelerations of a vertical strike-slip fault model is the topic of this study. The discrete wave number/finite element method was adopted to calculate the ground motion in the horizontal layered half space. An analysis of peak ground acceleration （PGA） indicates that similar to the sub-shear situation, directivity also exists in the super-shear situation. However, there are some differences as tbllows：（1） The PGA of the fault-normal component decreases with super-shear velocity, and the areas that were significantly affected by directivity in the PGA field changed from a cone-shaped region in the forward direction in a sub-shear situation to a limited near-fault region in a super-shear situation. （2） The PGA of the fault-parallel and vertical component is not as sensitive as the fault-normal component to the increasing super-shear velocity. （3） The PGA of the fault-normal component is not always greater than the fault-parallel component when the rupture velocity exceeds the shear wave velocity.

关键词： ground motion directivity rupture velocity super-shear rupture peak ground acceleration

Performance of DDA time integration

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Science China(Technological Sciences) 2015年第9期58卷 1558-1566页

作者： LIN ShaoZhong xie ZhiQiang Changjiang River Scientific Research Institute Research Center on Water Engineering Safety and Disaster Prevention of MWR DDA Center of Changjiang River Scientific Research Institute

Discontinuous deformation analysis(DDA) is a numerical method for analyzing the deformation of block system. It employs unified dynamic formulation for both static and dynamic analysis, in which the so-called kinetic damping is adopted for absorbing dynamic energy. The DDA dynamic equations are integrated directly by the constant acceleration algorithm of Newmark family integrators. In order to have an insight into the DDA time integration scheme, the performance of Newmark time integration scheme for dynamic equations with kinetic damping is systematically investigated, formulae of stability, bifurcation, spectral radius, critical kinetic damping and algorithmic damping are presented. Combining with numerical examples, recognition and suggestions of Newmark integration scheme application in the DDA static and dynamic analysis are proposed.

关键词： DDA time integration scheme performance analysis critical kinetic damping

RELATION BETWEEN WIENER NUMBERS OF QUASI-HEXAGONAL CHAINS AND QUASI-POLYOMINO CHAINS

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Journal of Systems Science & Complexity 2010年第4期23卷 873-882页

作者： Mingfang xie Fuji ZHANG College of Jinshan Fujian Agriculture and Forestry University Fuzhou 350002 China Fuji ZHANG Institute of Mathematics Xiamen University Xiamen 361005 China

Let Q_n and B_n denote a quasi-polyomino chain with n squares and a quasi-hexagonalchain with n hexagons,*** this paper,the authors establish a relation between the Wienernumbers of Q_n and B_n:W(Q_n)=1/4[W(B_n)-8/3n^3+(14)/3n+3].And the extremal quasi-polyominochains with respect to the Wiener number are ***,several classes of polyominochains with large Wiener numbers are ordered.

关键词： Hexagonal chain polyomino chain quasi-hexagonal chains quasi-polyomino chain Wiener number.