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DECISION-MAKING OF SLICING SCHEME IN FUSED DEPOSITION MODELING PROCESS BASED ON ANALYTICAL HIERARCHICAL PROCESS 被引量:6
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作者 张剑峰 彭安华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第2期125-130,共6页
Based on analyzing the influences of a slicing scheme on stair-stepping effect, supporting structure, efficiency and deformation, etc. , analytical hierarchical process (AHP) combining with fuzzy synthetic evaluatio... Based on analyzing the influences of a slicing scheme on stair-stepping effect, supporting structure, efficiency and deformation, etc. , analytical hierarchical process (AHP) combining with fuzzy synthetic evaluation is introduced to make decision in slicing schemes for a processing part. The application in determining the slicing scheme for a computer mouse during prototyping shows that the method increases the rationality during decision- making and improves quality and efficiency for the prototyping part. 展开更多
关键词 decision-making fused deposition modeling (FDM) analytical hierarchical process (AHP) slicing scheme
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A multi-objective decision-making method for the treatment scheme of landslide hazard 被引量:7
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作者 QuanminXie YuanyouXia 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期101-105,共5页
The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making o... The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making of treatment schemes of landslide hazard is aproblem of comprehensive judgment with multi-hierarchy and multi-objective. The traditional analysishierarchy process needs identity test. The traditional analysis hierarchy process is improved bymeans of optimal transfer matrix here. An improved hierarchy decision-making model for the treatmentof landslide hazard is set up. The judgment matrix obtained by the method can naturally meet therequirement of identity, so the identity test is not necessary. At last, the method is applied tothe treatment decision-making of the dangerous rock mass at the Slate Mountain, and its applicationis discussed in detail. 展开更多
关键词 landslide hazard treatment scheme improved hierarchy decision-making model optimal transfer matrix
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The Laplacian Energy of Hesitancy Fuzzy Graphs in Decision-Making Problems
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作者 N.Rajagopal Reddy Mohammad Zubair Khan +3 位作者 S.Sharief Basha Abdulrahman Alahmadi Ahmed H.Alahmadi Chiranji Lal Chowdhary 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2637-2653,共17页
Decision-making(DM)is a process in which several persons concur-rently engage,examine the problems,evaluate potential alternatives,and select an appropriate option to the problem.Technique for determining order prefer... Decision-making(DM)is a process in which several persons concur-rently engage,examine the problems,evaluate potential alternatives,and select an appropriate option to the problem.Technique for determining order preference by similarity to the ideal solution(TOPSIS)is an established DM process.The objective of this report happens to broaden the approach of TOPSIS to solve the DM issues designed with Hesitancy fuzzy data,in which evaluation evidence given by the experts on possible solutions is presents as Hesitancy fuzzy decision matrices,each of which is defined by Hesitancy fuzzy numbers.Findings:we represent analytical results,such as designing a satellite communication network and assessing reservoir operation methods,to demonstrate that our suggested thoughts may be used in DM.Aim:We studied a new testing method for the arti-ficial communication system to give proof of the future construction of satellite earth stations.We aim to identify the best one from the different testing places.We are alsofinding the best operation schemes in the reservoir.In this article,we present the concepts of Laplacian energy(LE)in Hesitancy fuzzy graphs(HFGs),the weight function of LE of HFGs,and the TOPSIS method technique is used to produce the hesitancy fuzzy weighted-average(HFWA).Also,consider practical examples to illustrate the applicability of thefinest design of satellite communication systems and also evaluation of reservoir schemes. 展开更多
关键词 Hesitancy fuzzy graphs(HFGs) laplacian energy satellite communication system reservoir operation schemes decision-making
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EFFECTS OF VERTICAL WIND SHEAR ON TROPICAL CYCLONE INTENSITY CHANGE 被引量:1
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作者 白莉娜 王元 《Journal of Tropical Meteorology》 SCIE 2016年第1期11-18,共8页
The effects of vertical wind shear on tropical cyclone(TC) intensity change are examined based on the TC data from the China Meteorological Administration and the NCEP reanalysis daily data from 2001 to 2006.First,the... The effects of vertical wind shear on tropical cyclone(TC) intensity change are examined based on the TC data from the China Meteorological Administration and the NCEP reanalysis daily data from 2001 to 2006.First,the influence of wind shear between different vertical levels and averages in different horizontal areas are compared.The results indicate that the effect of wind shear between 200 and 850 hPa averaged within a 200-800 km annulus on TC intensity change is larger than any other calculated vertical wind shear.High-latitude and intense TCs tend to be less sensitive to the effects of VWS than low-latitude and weak TCs.TCs experience time lags between the imposition of the shear and the weakening in TC intensity.A vertical shear of 8-9 m/s(9-10 m/s) would weaken TC intensity within 60 h(48 h).A vertical shear greater than 10 m/s would weaken TC intensity within 6 h.Finally,a statistical TC intensity prediction scheme is developed by using partial least squares regression,which produces skillful intensity forecasts when potential predictors include factors related to the vertical wind shear.Analysis of the standardized regression coefficients further confirms the obtained statistical results. 展开更多
关键词 tropical cyclone intensity change statistical analysis environmental vertical wind shear TC intensity prediction scheme
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S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3)的构筑及光催化还原CO_(2)性能 被引量:1
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作者 刘平 朱成才 +1 位作者 李艳阳 要红昌 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期197-208,共12页
通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽... 通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽进行光催化反应。优化后的材料光照5 h后CO_(2)还原产物CO和CH_(4)的产量分别为7.87和4.88μmol·g^(-1)。相对于单相组分,CO和CH_(4)的产量明显提高。光催化活性的提高,归因于ZnFe_(2)O_(4)和WO_(3)异质结的形成以及光生载流子的S型电荷传输模式。 展开更多
关键词 CO_(2)还原 光催化活性 ZnFe_(2)O_(4)/WO_(3) 异质结 S型电荷传输模式
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钢筋混凝土拱桥加固施工次序方案及效果评价 被引量:1
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作者 徐略勤 杨忠友 +2 位作者 周水兴 岳克锋 沈正璇 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期8-15,共8页
为研究钢筋混凝土拱桥最优的加固施工次序,以一座在役4跨箱形拱桥的加固方案为背景,设计了3组针对性的加固方案,并对不同拆除加固施工次序下的主拱圈力学性能进行了分析;采用恒载应力变化率(αD)和荷载效应变化率(αN)评价了施工中拱圈... 为研究钢筋混凝土拱桥最优的加固施工次序,以一座在役4跨箱形拱桥的加固方案为背景,设计了3组针对性的加固方案,并对不同拆除加固施工次序下的主拱圈力学性能进行了分析;采用恒载应力变化率(αD)和荷载效应变化率(αN)评价了施工中拱圈的应力变化规律及加固后原拱圈的荷载效应。研究结果表明:拱上结构的拆建次序对加固后主拱圈的力学性能影响较小,但对加固过程中主拱圈的受力状态影响较大;拱顶对称拆除时αD<0,结构处于“卸载”状态,有利于拱桥施工中的受力;αN随着拱上结构恒载减小而增大,且增速减缓,故加固层材料利用率也随拱上结构恒载减小而增大,且增幅变缓;αN越大,则加固效果越好。 展开更多
关键词 桥梁工程 钢筋混凝土拱桥 恒载应力变化率 荷载效应变化率 加固施工次序方案 效果评价
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南宁五化灌区马兰渡槽设计方案变更分析
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作者 刘惠娟 《广西水利水电》 2024年第1期85-89,共5页
根据全国最新“三区三线”划定成果,对原南宁市五化灌区马兰渡槽设计方案进行了变更。通过将原马兰渡槽设计方案与最新“三区三线”划定成果进行比较,提出了原址倒虹吸、原址渡槽两个设计变更方案。随后,从工程占地、地质条件、结构布... 根据全国最新“三区三线”划定成果,对原南宁市五化灌区马兰渡槽设计方案进行了变更。通过将原马兰渡槽设计方案与最新“三区三线”划定成果进行比较,提出了原址倒虹吸、原址渡槽两个设计变更方案。随后,从工程占地、地质条件、结构布置、施工运维等方面分析了各设计变更方案的优缺点,综合比选确定原址倒虹吸方案为最优设计方案。 展开更多
关键词 渡槽 倒虹吸 设计变更 方案比选 五化灌区
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湖相细粒沉积岩颗粒微观力学特征及类型划分——以鄂尔多斯盆地上三叠统延长组7段页岩为例
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作者 解馨慧 邓虎成 +5 位作者 胡蓝霄 李勇 毛金昕 刘佳杰 张鑫 李柏洋 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第4期1079-1088,共10页
细粒沉积岩蕴藏着丰富的油气资源,为了研究细粒沉积岩颗粒微观结构及力学特征,以鄂尔多斯盆地上三叠统延长组7段细粒沉积岩为例,开展了扫描电镜观察和纳米压痕实验分析,据此研究细粒沉积颗粒的几何特征和微观力学性质。研究认为:用粒径... 细粒沉积岩蕴藏着丰富的油气资源,为了研究细粒沉积岩颗粒微观结构及力学特征,以鄂尔多斯盆地上三叠统延长组7段细粒沉积岩为例,开展了扫描电镜观察和纳米压痕实验分析,据此研究细粒沉积颗粒的几何特征和微观力学性质。研究认为:用粒径、扁平度、棱角性、硬度和弹性模量5个特征参数,可将细粒沉积岩划分为粒度+棱角型、扁平度+棱角型、扁平度+棱角+弹性模量+硬度型、弹性模量+硬度型、棱角+弹性模量+硬度型和粒度+棱角+弹性模量型6种主要颗粒类型;接着,根据颗粒类型的相对含量,进一步将颗粒类型划分为5种组合类型;最后,分析了细粒沉积颗粒类型与矿物类型之间的耦合关系。细粒沉积岩颗粒微观分类方案的建立,有助于理解细粒沉积岩微观结构特征,预测地质“甜点”空间分布,对细粒沉积岩的油气资源评价和效益开发具有重要的理论和科学意义。 展开更多
关键词 扫描电镜 纳米压痕 分类方案 细粒沉积岩颗粒 页岩 延长组7段 鄂尔多斯盆地
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多巴胺配色在“Z世代”群体中的流行因素及产品设计探析
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作者 周澍天 《色彩》 2024年第4期31-33,共3页
文章从近年网络流行的名词“多巴胺配色”概念入手,分析多巴胺配色的视觉特点、发展历史及其背后的社会文化心理。旨在探讨多巴胺配色产品设计策略在“Z世代”中的流行因素,并通过现实中各类商业品牌案例来进一步解析多巴胺配色在设计... 文章从近年网络流行的名词“多巴胺配色”概念入手,分析多巴胺配色的视觉特点、发展历史及其背后的社会文化心理。旨在探讨多巴胺配色产品设计策略在“Z世代”中的流行因素,并通过现实中各类商业品牌案例来进一步解析多巴胺配色在设计中的应用和影响。 展开更多
关键词 “Z世代” 多巴胺配色 审美变化
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相变蓄冷材料研究进展
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作者 仇豆豆 翟鑫钰 +2 位作者 阮春晨 彭孝天 彭浩 《新能源科技》 2024年第3期1-14,共14页
相变蓄冷材料具有储能密度高、相变温度可控、循环稳定性强的优点,成为目前最有发展前景的储能方式。文章对现有的相变蓄冷材料进行了分类,总结了不同类型材料的优缺点,重点介绍了国内外学者在固-液相变方面的研究进展,罗列了各种材料... 相变蓄冷材料具有储能密度高、相变温度可控、循环稳定性强的优点,成为目前最有发展前景的储能方式。文章对现有的相变蓄冷材料进行了分类,总结了不同类型材料的优缺点,重点介绍了国内外学者在固-液相变方面的研究进展,罗列了各种材料的热物性和化学特性,对其在医疗冷链、建筑制冷、生鲜冷冻等具体应用中的研究进行了阐述。在此基础上,针对目前相变蓄冷材料存在的导热率低、腐蚀性强、易泄漏和过冷度大等问题,文章提出相应的解决方案并阐述改善机理,对相变蓄冷材料的未来发展进行了展望。 展开更多
关键词 蓄冷 相变材料 分类 应用领域 优化方案
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不同地质情况下围护结构变更方案可行性研究
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作者 朱彩云 《建筑技术开发》 2024年第7期27-29,共3页
在不同地质情况下,如何有效进行围护结构的施工变更,并分析其对工程费用的影响以确定可行性方案,实际施工中提出施工变更管理策略已成为工程管理中一项重要任务。研究结合工程实例,在不同地质情况下探讨围护结构变更方案,并研究其对工... 在不同地质情况下,如何有效进行围护结构的施工变更,并分析其对工程费用的影响以确定可行性方案,实际施工中提出施工变更管理策略已成为工程管理中一项重要任务。研究结合工程实例,在不同地质情况下探讨围护结构变更方案,并研究其对工程造价和进度的影响,从而提出了此类工程变更管理研究的方向,旨在为类似项目的施工应用提供参考价值。 展开更多
关键词 不同地质 围护结构 变更方案
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基坑分仓法施工变更及对既有近邻隧道的影响研究
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作者 米向东 《广东土木与建筑》 2024年第6期43-47,共5页
有时近邻既有结构基坑开挖过程中需要进行方案变更,施工方案往往也需要进行相应改变以确保既有近邻结构的安全服役。依托珠海市某近邻既有城轨隧道的基坑分仓开挖工程,对增加地下行车通道后的施工方案进行变更,并借助商业有限元软件模... 有时近邻既有结构基坑开挖过程中需要进行方案变更,施工方案往往也需要进行相应改变以确保既有近邻结构的安全服役。依托珠海市某近邻既有城轨隧道的基坑分仓开挖工程,对增加地下行车通道后的施工方案进行变更,并借助商业有限元软件模拟基坑分仓施工过程,对基坑开挖过程围护结构与近邻隧道进行响应评价,并结合工程实测数据进行了安全评估分析。结果表明,在改变后的分仓法施工方案下,基坑围护结构、既有隧道结构及隧道内铁轨变形均满足控制要求。同时,围护结构实际测量结果与数值模拟结果相近,且整体规律与数值模拟结果相符合。由此,近邻既有隧道的基坑分仓开挖施工变更后方案的可行性得到验证。 展开更多
关键词 近邻既有隧道 基坑开挖 分仓法 数值模拟 施工方案变更
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Defending Against Link Failure in Virtual Network Embedding Using a Hybrid Scheme 被引量:3
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作者 Jianjian Ai Hongchang Chen +1 位作者 Zehua Guo Guozhen Cheng 《China Communications》 SCIE CSCD 2019年第1期129-138,共10页
Nowadays network virtualization is utterly popular.As a result,how to protect the virtual networks from attacking on the link is increasingly important.Existing schemes are mainly backup-based,which suffer from data l... Nowadays network virtualization is utterly popular.As a result,how to protect the virtual networks from attacking on the link is increasingly important.Existing schemes are mainly backup-based,which suffer from data loss and are helpless to such attacks like data tampering.To offer high security level,in this paper,we first propose a multipath and decision-making(MD) scheme which applies multipath simultaneously delivery and decision-making for protecting the virtual network.Considering different security requirement for virtual link,we devise a hybrid scheme to protect the virtual links.For the critical links,MD scheme is adopted.For the other links,we adopt the Shared Backup Scheme.Our simulation results indicate the proposed scheme can significantly increase the security level of the critical link high in the loss of less acceptance ratio. 展开更多
关键词 network VIRTUALIZATION VIRTUAL LINK security MULTIPATH and decision-making hybrid scheme
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Inclusion of forestry offsets in emission trading schemes:insights from global experts 被引量:4
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作者 Anil Shrestha Sarah Eshpeter +3 位作者 Nuyun Li Jinliang Li John O.Nile Guangyu Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期279-287,共9页
Emissions trading schemes(ETSs)have been a central component of international climate change policies,as a carbon pricing tool to achieve emissions reduction targets.Forest carbon offset credits have been leveraged in... Emissions trading schemes(ETSs)have been a central component of international climate change policies,as a carbon pricing tool to achieve emissions reduction targets.Forest carbon offset credits have been leveraged in many ETSs to efficiently meet emission reduction targets,yet there is little knowledge about the perceptions,experiences,and challenges associated with the forest carbon offsetting in existing and pilot ETS.Given that the future inclusion of forest carbon offset in ETS management activities and policies will require strong support and acceptability among the institutions and experts involved in ETS,this study explores the experiences and lessons learned with 16 globally engaging experts representing major existing ETSs(North America,Europe,and New Zealand)and Chinese pilot ETSs towards the inclusion of forestry offsets,major concerns and challenges with existing implementation models.Findings revealed that many respondents particularly from North America,New Zealand,and Chinese pilot systems portrayed positive attitudes toward the inclusion of forestry carbon offsets and its role in contributing to a viable ETS,while European experts were not supportive.Respondents cited leakage,permanence,additionality,and monitoring design features as the major challenges and concerns that inhibit the expansion and inclusion of forest carbon offsetting.Respondents from Chinese pilot schemes referenced a unique set of challenges related to implementation,including the increasing cost of afforestation and reforestation projects,the uncertainty in the future supply and demand for their national Certified Emissions Reduction(CER)scheme and landowner engagement.Existing and future ETSs should learn from and address the challenges experienced by global experts and carbon pricing mechanisms to design,evaluate,or enhance their forest carbon offset programs for an effective and viable system that successfully contributes to GHG mitigation practices globally.We recommend inclusion of forest carbon offsets at the early stages of ETS improves the perceptions and experience of policy makers and practitioners toward the success and potential of forestry offsets in ETS ensuring familiarity and confidence in the mechanism. 展开更多
关键词 Emission trading scheme Forest carbon offsets Climate change Cap and trade Carbon
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Policy Diffusion of the Emission Trading Scheme in China:Progress and Prospects
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作者 Fang-Ting Cheng 《Chinese Business Review》 2020年第4期105-119,共15页
Chinese national emissions trading scheme(ETS)of greenhouse gas(GHG)was scheduled to start simulation trading in the power sector in 2020.Now it is good timing to review its progress and prospect.This study first exam... Chinese national emissions trading scheme(ETS)of greenhouse gas(GHG)was scheduled to start simulation trading in the power sector in 2020.Now it is good timing to review its progress and prospect.This study first examines policy diffusion in relation ETSs in China and particularly those for CO2 emissions,including the causes,determinants,process,and impacts.It argues in a centralized political system with highly and widely differentiated local circumstances,policy diffusion is progressed through a more complicated process,presented as a three-tier process in the paper,illustrating how international arrangement,national jurisdiction,and local administration interact and influence policy-making in a follower’s jurisdiction.China,which is now the biggest GHG emitter,has been preparing to establish a national ETS since 2017.So far,eight sub-national governments have introduced ETS pilot programs to feedback their experiences and to determine best practice for the national scheme.These eight pilots,especially the relatively successful ones,are found to be motivated by a competitive relationship that aims to stabilize its carbon market,which may eventually contribute to the progress of policy diffusion of the ETS in China. 展开更多
关键词 emissions trading scheme(ETS) greenhouse gas climate change EUETS pilot ETS Kyoto Protocol Paris Agreement
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基于生态系统服务价值和景观生态风险的生态分区识别与优化策略——以祁连山国家公园青海片区为例 被引量:24
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作者 乔斌 曹晓云 +9 位作者 孙玮婕 高雅月 陈奇 于红妍 王喆 王乃昂 程弘毅 王义鹏 李甫 周秉荣 《生态学报》 CAS CSCD 北大核心 2023年第3期986-1004,共19页
生态空间分区识别是支撑自然保护地生态资产管理的前提性和基础性工作。以祁连山国家公园青海片区(以下简称为“园区”)为例,集成遥感技术、地理信息模型方法、景观生态学方法、GIS格网法,分析了园区1998—2018年土地利用、生态系统服... 生态空间分区识别是支撑自然保护地生态资产管理的前提性和基础性工作。以祁连山国家公园青海片区(以下简称为“园区”)为例,集成遥感技术、地理信息模型方法、景观生态学方法、GIS格网法,分析了园区1998—2018年土地利用、生态系统服务价值、景观生态风险的时空演变特征,选用Z-score标准化构建了四类生态分区。结果表明:(1)草地占园区面积的55.00%以上,30年间(1998—2018年)园区土地利用之间转移总面积为102.49 km^(2)。(2)3个时期(1998年、2008年、2018年)园区生态系统服务价值(ESV)约为274亿元/a,单位面积ESV为172.94万元/km^(2)。不同ESV等级呈现“大分散、小集聚”的镶嵌交错分布格局,高寒河源湿地区和寒温带针叶林区为ESV的高值区。(3)3个时期园区景观生态风险指数(ERI)分别为0.2287、0.2286和0.2310,生态安全状态整体较好,景观生态风险以低生态风险等级和较低生态风险等级占主导地位,占园区面积的90.00%左右。人工牧草地、旱地、建设用地的景观生态风险等级较高。(4)结合生态系统服务价值和景观生态风险两个维度将园区划分为生态保障型生境修复区(I)、生态脆弱型特别保护区(II)、生态改良型发展利用区(III)和生态预防型保育涵养区(IV)四类生态分区,并提出差异化管控方案。 展开更多
关键词 土地利用变化 生态系统服务 生态风险 生态分区 管控方案
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基于产品多域信息关联约束网络模型的设计变更方案决策方法 被引量:1
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作者 张元戎 郭伟 +1 位作者 王磊 孙江 《包装工程》 CAS 北大核心 2023年第8期61-71,共11页
目的 随着客户需求向个性化、多样化转变,市场对企业设计需求响应能力提出了更高的要求。方法 为实现快速精准的产品变更,提出了一种基于产品多域关联约束网络模型的变更设计方案决策方法。构建了基于产品功能域-参数域-结构域多域关联... 目的 随着客户需求向个性化、多样化转变,市场对企业设计需求响应能力提出了更高的要求。方法 为实现快速精准的产品变更,提出了一种基于产品多域关联约束网络模型的变更设计方案决策方法。构建了基于产品功能域-参数域-结构域多域关联约束的网络模型,提出了基于该模型的变更影响传播模式,提出了以网络节点代价与连边代价指标为基础的产品变更方案决策方法,以土压平衡盾构机螺旋输送机的变更为例验证了该方法的有效性。结果 结果表明,该决策方法可以快速获得产品多域设计信息变更方案,同时有效减小变更影响的传播范围。结论 对企业提高需求响应速度、提高变更设计效率、降低产品变更成本来说具有重要意义。 展开更多
关键词 变更设计 多层网络模型 变更传播代价计算 变更方案决策
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海岸分类的回顾与展望 被引量:1
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作者 贾建军 于谦 高抒 《海洋通报》 CAS CSCD 北大核心 2023年第6期601-616,共16页
海岸带是陆地与海洋相交的区域,受到多种自然和人为因素的影响,进行合理的海岸分类对于科学认识、合理开发、有效管理和保护海岸带资源至关重要。本文回顾海岸带分类的研究历程,探讨不同分类方案的划分依据,并强调海岸带的多维性和复杂... 海岸带是陆地与海洋相交的区域,受到多种自然和人为因素的影响,进行合理的海岸分类对于科学认识、合理开发、有效管理和保护海岸带资源至关重要。本文回顾海岸带分类的研究历程,探讨不同分类方案的划分依据,并强调海岸带的多维性和复杂性。从早期的地理地貌特征划分到现代的综合性海岸分类体系,海岸带分类方案不断演变,并受到各个时代的资料积累、知识体系、观测技术及制图展示效果等方面的深刻影响。不同国家和地区的学者在分类方案上存在一定的差异,体现了各地的地理地质背景、研究重点、开发利用方式等方面的特点,也隐含着研究人员的观察视角。主要源于陆地的物质属性和主要源于海洋的能量条件,越来越成为海岸分类的重要指标。人类活动对海岸带的影响不容忽视,人工海岸的比例已经迅速上升,但在海岸带分类体系中的研究仍有所欠缺,原因包括世界观、方法论和价值观等多个层面。建议从海岸动力作用环境和沉积物供应条件两方面考虑人类活动如何影响海岸带系统状态,而海岸带类别体系里可以增加人工建造和人工改造两个新的大类。通过深化分类方法和细化分类层次,同时向综合与细化两个方向推动海岸分类体系研究,可以更好地实现海岸带资源的保护与可持续利用,促进人与自然的和谐共存。 展开更多
关键词 海岸带 分类方案 沉积物 环境变化 人工岸线 人类活动
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Dynamic-statistics combined forecast scheme based on the abrupt decadal change component of summer precipitation in East Asia 被引量:8
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作者 GONG ZhiQiang ZHAO JunHu +1 位作者 FENG GuoLin CHOU JiFan 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第3期404-419,共16页
Based on the 1983~2011 CMAP data,the precipitation anomaly in East Asia and its nearby sea regions(hereafter called East Asia for short) demonstrates the "+-+" pattern before 1999 and the "-+-" pattern afterw... Based on the 1983~2011 CMAP data,the precipitation anomaly in East Asia and its nearby sea regions(hereafter called East Asia for short) demonstrates the "+-+" pattern before 1999 and the "-+-" pattern afterwards; this decadal change is contained principally in the corresponding EOF3 component.However,the NCC_CGCM forecast results are quite different,which reveal the "+-+-" pattern before 1999 and the "-+-+" pattern afterwards.Meanwhile,the probability of improving NCC_CGCM's forecast accuracy based on these key SST areas is discussed,and the dynamic-statistics combined forecast scheme is constructed for increasing the information of decadal change contained in the summer precipitation in East Asia.The independent sample forecast results indicate that this forecasting scheme can effectively modify the NCC_CGCM's decadal change information contained in the summer precipitation in East Asia(especially in the area of 30°N–55°N).The ACC is 0.25 and ACR is 61% for the forecasting result based on the V SST area,and the mean ACC is 0.03 and ACR is 51% for the seven key areas,which are better than NCC_CGCM's system error correction results(ACC is -0.01 and ACR is 49%).Besides,the modified forecast results also provide the information that the precipitation anomaly in East Asia mainly shows the "+-+" pattern before 1999 and the "-+-" pattern afterwards. 展开更多
关键词 abrupt decadal change dynamic-statistics combined forecast scheme summer precipitation East Asia sea surface temperature
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新形势下对减少高速公路水土保持方案变更的思考——以四川省为例 被引量:1
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作者 王章文 肖莉 +2 位作者 彭志忠 宋炜 贺曦 《山西水土保持科技》 2023年第1期14-16,50,共4页
四川省位于我国地势第一、二级阶梯的过渡带,分布了山地、丘陵、台地和平原等四种地貌,地形地貌组成多样。近年来,四川省高速公路建设逐布向高寒高海拔区和深切峡谷区推进,工程地质条件、工程结构极其复杂,土石方量极其巨大。基于工程... 四川省位于我国地势第一、二级阶梯的过渡带,分布了山地、丘陵、台地和平原等四种地貌,地形地貌组成多样。近年来,四川省高速公路建设逐布向高寒高海拔区和深切峡谷区推进,工程地质条件、工程结构极其复杂,土石方量极其巨大。基于工程可行性研究深度的水土保持方案,在后续设计和施工过程中,频繁出现水土保持方案变更问题,如何减少水土保持方案变更,是值得探索的问题。本文以四川艰险山区高速公路水土保持方案变更为例,分析导致高速公路水土保持方案变更的主要原因是以主体可行性研究阶段作为水土保持方案编制依据,提出了将高速公路水土保持方案编制阶段推迟至初步设计阶段或施工图设计阶段,是减少高速公路水土保持方案变更的主要对策之一,可为今后减少高速公路水土保持方案变更提供参考。 展开更多
关键词 高速公路 水土保持方案变更 新形势
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