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多工位夹具设计中的分层结构法
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作者 傅兴森 姜静 杨占良 《机床》 CSCD 1993年第8期14-15,共2页
关键词 多工位夹具 分层结构法 设计
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中国出口增速下降的驱动因素研究——基于全球价值链分工的分层结构分解分析 被引量:8
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作者 葛阳琴 谢建国 《数量经济技术经济研究》 CSSCI CSCD 北大核心 2018年第2期24-43,共20页
研究目标:研究2011~2014年中国出口增速下降的驱动因素。研究方法:从增加值贸易视角运用分层式结构分解法(HSDA)。研究发现:中国出口增速下降既有周期性因素,也有结构性因素;其中,国外需求下降是决定性因素,贡献度为85.9%,受需求水平下... 研究目标:研究2011~2014年中国出口增速下降的驱动因素。研究方法:从增加值贸易视角运用分层式结构分解法(HSDA)。研究发现:中国出口增速下降既有周期性因素,也有结构性因素;其中,国外需求下降是决定性因素,贡献度为85.9%,受需求水平下降和需求结构变化共同影响;生产分工变化是重要影响因素,贡献度为13.6%,主要受前向产业关联变化和国内生产分工调整影响;增加值系数变化影响较小,仅为0.5%。研究创新:基于GMRIO模型将多种因素纳入统一的分析框架,定量分析各因素对中国出口增速下降的影响。研究价值:对处于转型期的中国外贸维持出口平稳增长有重要的现实意义和实践价值。 展开更多
关键词 增加值出口 国外需求 全球生产分工 分层结构分解
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Hierarchical Semantic-Category-Tree Model for Chinese-English Machine Translation 被引量:1
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作者 Zhu Xiaojian Jin Yaohong 《China Communications》 SCIE CSCD 2012年第12期80-92,共13页
We introduce a novel Sermntic-Category- Tree (SCT) model to present the sen-antic structure of a sentence for Chinese-English Machine Translation (MT). We use the SCT model to handle the reordering in a hierarchic... We introduce a novel Sermntic-Category- Tree (SCT) model to present the sen-antic structure of a sentence for Chinese-English Machine Translation (MT). We use the SCT model to handle the reordering in a hierarchical structure in which one reordering is dependent on the others. Different from other reordering approaches, we handle the reordering at three levels: sentence level, chunk level, and word level. The chunk-level reordering is dependent on the sentence-level reordering, and the word-level reordering is dependent on the chunk-level reordering. In this paper, we formally describe the SCT model and discuss the translation strategy based on the SCT model. Further, we present an algorithm for analyzing the source language in SCT and transforming the source SCT into the target SCT. We apply the SCT model to a role-based patent text MT to evaluate the ability of the SCT model. The experimental results show that SCT is efficient in handling the hierarehical reordering operation in MT. 展开更多
关键词 REORDERING SCT MT function word
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Hierarchically skeletal multi-layered Pt-Ni nanocrystals for highly efficient oxygen reduction and methanol oxidation reactions 被引量:6
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作者 Shibo Li Zhi Qun Tian +5 位作者 Yang Liu Zheng Jang Syed Waqar Hasan Xingfa Chen Panagiotis Tsiakaras Pei Kang Shen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第4期648-657,共10页
Pt based materials are the most efficient electrocatalysts for the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR)in fuel cells.Maximizing the utilization of Pt based materials by modulating their m... Pt based materials are the most efficient electrocatalysts for the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR)in fuel cells.Maximizing the utilization of Pt based materials by modulating their morphologies to expose more active sites is a fundamental objective for the practical application of fuel cells.Herein,we report a new class of hierarchically skeletal Pt-Ni nanocrystals(HSNs)with a multi-layered structure,prepared by an inorganic acid-induced solvothermal method.The addition of H_(2)SO_(4)to the synthetic protocol provides a critical trigger for the successful growth of Pt-Ni nanocrystals with the desired structure.The Pt-Ni HSNs synthesized by this method exhibit enhanced mass activity of 1.25 A mgpt−1 at 0.9 V(versus the reversible hydrogen electrode)towards ORR in 0.1-M HClO_(4),which is superior to that of Pt-Ni multi-branched nanocrystals obtained by the same method in the absence of inorganic acid;it is additionally 8.9-fold higher than that of the commercial Pt/C catalyst.Meanwhile,it displays enhanced stability,with only 21.6%mass activity loss after 10,000 cycles(0.6–1.0 V)for ORR.Furthermore,the Pt-Ni HSNs show enhanced activity and anti-toxic ability in CO for MOR.The superb activity of the Pt-Ni HSNs for ORR and MOR is fully attributed to an extensively exposed electrochemical surface area and high intrinsic activity,induced by strain effects,provided by the unique hierarchically skeletal alloy structure.The novel open and hierarchical structure of Pt-Ni alloy provides a promising approach for significant improvements of the activity of Pt based alloy electrocatalysts. 展开更多
关键词 Hierarchically skeletal Pt-Ni NANOCRYSTALS SELF-ASSEMBLY Solvent thermal method Oxygen reduction reaction Methanol oxidation reaction Fuel cells ACTIVITY
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The mechanical response of multi-tower continuous-span suspension bridge deck pavement based on whole bridge analysis
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作者 Li Hongtao Zhang Chenchen +1 位作者 Hu Jing Qian Zhendong 《Engineering Sciences》 EI 2011年第2期88-92,共5页
The effect of multiple span suspension structure on the mechanical response of bridge deck pavement was studied, and finite element analysis (FEM) of stress and strain of pavement according to the bridge floor system ... The effect of multiple span suspension structure on the mechanical response of bridge deck pavement was studied, and finite element analysis (FEM) of stress and strain of pavement according to the bridge floor system features of super-long and high flexibility was made. Meanwhile, the FEM results were compared with those of the single span suspension structure. Three-stage analytic hierarchy process (AHP) is developed to analyze the mechanical response including whole bridge analysis, partial beams section analysis and orthotropic plate analysis. The most unfavorable load position was determined by the numerical solutions acquired from each stage to study the main mechanical index of multiple span suspension structure. The FEM results showed that the mechanical response numerical solutions by using the three-stage AHP are greater than those by simplified boundary condition, and the force condition of multiple span suspension structure is worse than that of the single span suspension structure. 展开更多
关键词 the multiple span suspension structure a three-stage analytic hierarchy process finite element analysis (FEM) the mechanical response of bridge deck pavement
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Dynamic Time Division Multiple Access Algorithm for Industrial Wireless Hierarchical Sensor Networks
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作者 杨彦红 张晓彤 +1 位作者 罗琼 李文超 《China Communications》 SCIE CSCD 2013年第5期137-145,共9页
Industrial wireless sensor networks adopt a hierarchical structure with large numbers of sensors and routers. Time Division Multiple Access (TDMA) is regarded as an efficient method to reduce the probability of confli... Industrial wireless sensor networks adopt a hierarchical structure with large numbers of sensors and routers. Time Division Multiple Access (TDMA) is regarded as an efficient method to reduce the probability of confliction. In the intra-cluster part, the random color selection method is effective in reducing the retry times in an application. In the inter-cluster part, a quick assign algorithm and a dynamic maximum link algorithm are proposed to meet the quick networking or minimum frame size requirements. In the simulation, the dynamic maximum link algorithm produces higher reductions in the frame length than the quick assign algorithm. When the number of routers is 140, the total number of time slots is reduced by 25%. However, the first algorithm needs more control messages, and the average difference in the number of control messages is 3 410. Consequently, the dynamic maximum link algorithm is utilized for adjusting the link schedule to the minimum delay with a relatively high throughput rate, and the quick assign algorithm is utilized for speeding up the networking process. 展开更多
关键词 TDMA wireless sensor network industrial wireless sensor network
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A Methodology for Bridge Condition Evaluation
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作者 Maria Rashidi Peter Gibson 《Journal of Civil Engineering and Architecture》 2012年第9期1149-1157,共9页
Due to the substantial role of bridges in transportation networks and in accordance with the limited funding for bridge management, remediation strategies have to be prioritised. A conservative bridge assessment will ... Due to the substantial role of bridges in transportation networks and in accordance with the limited funding for bridge management, remediation strategies have to be prioritised. A conservative bridge assessment will result in unnecessary actions, such as costly bridge strengthening or repairs. On the other hand, any bridge maintenance negligence and delayed actions may lead to heavy future costs or degraded assets. The accuracy of decisions developed by any manager or bridge engineer relies on the accuracy of the bridge condition assessment which emanates from visual inspection. Many bridge rating systems are based on a very subjective procedure and are associated with uncertainty and personal bias. The developing condition rating method described herein is an important step in adding more holism and objectivity to the current approaches. Structural importance and material vulnerability are the two main factors that should be considered in the evaluation of element structural index and the causal factor as the representative of age, environment, road class and inspection is implemented as a coefficient to the OSCI (overall structural condition index). The AHP (analytical hierarchy process) has been applied to evaluate the priority vector of the causal parameters. 展开更多
关键词 BRIDGE INSPECTION condition assessment structural importance material vulnerability causal factor AHP OSCI.
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Decision Support Scheme for Lishan Landslide Prewarning System 被引量:1
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作者 Miau Bin Su I Hui Chen 《Journal of Civil Engineering and Architecture》 2011年第8期706-714,共9页
This study combines the analytical model to build a landside monitoring decision support system of the Web GIS. The landslide area of Lishan is a case study for the research. The analysis of the risk degree for the la... This study combines the analytical model to build a landside monitoring decision support system of the Web GIS. The landslide area of Lishan is a case study for the research. The analysis of the risk degree for the landslide area in Lishan is based on the three-layer architecture of Fuzzy Analytic Hierarchical Process (FAHP). There are four fuzzy model structures used in monitoring devices: rainfall, groundwater level, Time Domain Reflectometry (TDR) monitored the subsurface deformation, and Global Positioning System (GPS) monitored ground displacement. These structures are relative to four membership functions that are used to classify four states, including safety, attention, warning, and danger. The risk degree of the landslide area can be obtained through the fuzzy rules by determining management criteria. Calculating the total scores of historical monitoring record of the rainfall, groundwater level, TDR, and GPS through the fuzzy theory can determine the analytical results of risk degrees in Lishan landslide area. In this whole area, management criterion is in the state of attention when the total score is larger than 72, in the state of warning when total score is larger than 95, and in the state of danger when total score is larger than 113. The system provides real-time monitoring data, and prewarning decision support in order to announce and prevent the disaster at the earliest time. 展开更多
关键词 Slope monitoring decision support system fuzzy theory Web 3D GIS.
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RESEARCH ON DEEP COAL SEAM MINING FLOOR STARTA WATER BURSTING INFLUENCED FACTORS BASED ON ANALYTIC HIERACHY PROCESS
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作者 SUN Ming ZHENG Wenxiang DUAN Xiaobo 《International Journal of Technology Management》 2014年第4期135-138,共4页
Deep coal seam mining floor strata water bursting is a complicate nonlinear system, whose factors are coupling and influencing themselves. It built the analytic structure model for deep coal seam mining floor strata w... Deep coal seam mining floor strata water bursting is a complicate nonlinear system, whose factors are coupling and influencing themselves. It built the analytic structure model for deep coal seam mining floor strata water bursting, the judgment matrix was found by the expert scoring method, the contribution weights of the influenced factors were given out by the equation analytic process. The thirteen controlling factors and five main controlling factors were put award by analyzing weights, so the result was basically conform to the field practice. The expert scoring method and analytic process can convert the objective fact to the subjective cognition, so it is a method that can turn the qualitative into the quantitative. This can be relative objectively and precisely to study the question of many factors and grey box. 展开更多
关键词 deep coal seam mining floor strata water bursting expert scoring method equation analytic hierachy process controllingfactors main controlling factors
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Measuring the Complexity of Business Organization and Business Software Using Analytic Hierarchy Process (AHP)
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作者 Alen Jakupovie Mile Pavlie 《Computer Technology and Application》 2011年第9期736-747,共12页
The paper shows a proposition of metrics for measuring the complexity of the business organization and business software. The metrics is based on a subjective estimation of complexity of the elements from a part of th... The paper shows a proposition of metrics for measuring the complexity of the business organization and business software. The metrics is based on a subjective estimation of complexity of the elements from a part of the structure of business organization or business software in relation to other elements from the observed part. Estimation is performed based on the measuring scale for comparison of complexity of elements, and reaching a final conclusion on the complexity of elements in relation to other elements, through the Analytic Hierarchy Process (AHP). Defined in this manner, the metrics represents a unique metrics for measuring the complexity of elements of business organization and business software, which enables their comparison. The paper also presents a short overview of existing metrics for measuring the complexity of business organization and business software. 展开更多
关键词 Analytic hierarchy process (AHP) business organization business software COMPLEXITY metrics
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本土市场需求对全球价值链功能升级的贡献——基于多区域投入产出视角 被引量:1
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作者 张亚斌 曾灿 王振国 《国际贸易问题》 CSSCI 北大核心 2023年第2期39-56,共18页
促进价值链迈向中高端已成为中国经济高质量发展的必然要求。本文基于全球多区域投入产出模型测算和比较分析了1999—2014年国家和行业层面最终需求对功能活动增加值拉动效应的演变趋势,并采用分层式结构分解法重点考察了国内需求变动... 促进价值链迈向中高端已成为中国经济高质量发展的必然要求。本文基于全球多区域投入产出模型测算和比较分析了1999—2014年国家和行业层面最终需求对功能活动增加值拉动效应的演变趋势,并采用分层式结构分解法重点考察了国内需求变动对价值链功能升级的影响。测算结果显示:研究样本期间,最终需求功能活动增加值拉动效应呈持续增长态势,但仍存在制造活动增加值占比过高而导致升级情况有限。初步分解结果表明:功能增加值系数变动抑制了功能升级,投入产出结构有利于功能升级,最终需求尤其是国内需求变动极大地促进了功能升级。分层式分解结果显示:需求规模扩张是价值链功能升级的第一大驱动因素,且消费和投资需求规模影响效应趋于收敛;需求构成结构中消费需求尤其是家庭消费需求不足是制约价值链功能升级的主要因素;需求产品结构中对资本和知识密集型服务业产品的需求有效助推了功能升级。基于本土需求视角分析全球价值链功能升级,可以为中国打破“低端锁定”困境,避免落入“功能分工陷阱”,顺利实现价值链攀升提供新的思路。 展开更多
关键词 需求规模 需求结构 全球价值链功能升级 分层结构分解
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A versatile solution-phase, precursor route to surface-mazelike hierarchical structures
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作者 Ji Ma Lianchao Han Kezheng Chen 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第4期620-626,共7页
In this work, surface-mazelike Zn O, Cu, and Ni hierarchical structures were synthesized via a versatile ethylene glycol- mediated solvothermal method. The structure evolution of these materials bore striking similari... In this work, surface-mazelike Zn O, Cu, and Ni hierarchical structures were synthesized via a versatile ethylene glycol- mediated solvothermal method. The structure evolution of these materials bore striking similarities, including(1) initial formation of metal alkoxides precursors and(2) subsequent structural evolution of products from tiered plates to jigsaw puzzles; then to extrusion ridges, nests and spindles; and thereafter to final mazelike structures driven by persistent thermal decomposition of preformed precursors. Based on their unique surface morphologies in sinuous asymmetry, it is anticipated that such mazelike hierarchical structures may shed new light on the development of morphology-controlled adsorption and heterogeneous catalysts. 展开更多
关键词 hierarchical structure versatile precursor route mazelike SOLVOTHERMAL ADSORPTION
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OPTIMAL HIERARCHY STRUCTURES FOR MULTI-ATTRIBUTE-CRITERIA DECISIONS 被引量:2
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作者 Stan LIPOVETSKY 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第2期228-242,共15页
A problem of a hierarchy structure optimization is considered.Hierarchical structures arewidely used in the Analytic Hierarchy Process,conjoint analysis,and various other methods of multiplecriteria decision making.Th... A problem of a hierarchy structure optimization is considered.Hierarchical structures arewidely used in the Analytic Hierarchy Process,conjoint analysis,and various other methods of multiplecriteria decision making.The problem consists in finding a structure that needs a minimum number ofpair comparisons for a given total number of the alternatives.For an optimal hierarchy,the minimumefforts are needed for eliciting data and synthesizing the local preferences across the hierarchy to getthe global priorities or utilities.Special estimation techniques are developed and numerical simulationsperformed.Analytical and numerical results suggest optimal ways of priority evaluations for practicalmanagerial decisions in a complex environment. 展开更多
关键词 Analytic Hierarchy Process conjoint analysis hierarchy optimization pair comparisons.
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