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有QoS保证能力分组交换网络的体系结构设计
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作者 刘文波 杨梅樾 +1 位作者 郭云飞 刘力雄 《信息工程大学学报》 2009年第3期340-343,共4页
通过对理想化分组交换网络功能的形式化描述,说明了互联网在QoS保证方面存在的不足,分析了互联网对交互式实时业务无法提供服务质量保证的原因,为支持服务质量保证功能,从体系结构角度提出并论证了理想化分组交换网络体系结构应创设的... 通过对理想化分组交换网络功能的形式化描述,说明了互联网在QoS保证方面存在的不足,分析了互联网对交互式实时业务无法提供服务质量保证的原因,为支持服务质量保证功能,从体系结构角度提出并论证了理想化分组交换网络体系结构应创设的两个新的设计原则。 展开更多
关键词 QOS保证 分组网络体系结构 设计原则
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多层重力-侧力系统可分组合结构体系力学性能分析 被引量:2
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作者 赵鹤 李子昂 陶慕轩 《建筑钢结构进展》 CSCD 北大核心 2021年第10期44-53,共10页
针对装配式组合结构的发展需求,提出了一种多层重力-侧力系统可分组合结构体系,通过梁端铰接实现了结构的竖向承重系统与水平抗侧力系统的分离,提升了装配式组合结构的标准化程度。根据该结构体系的布置方案,设计并完成了3个大比例体系... 针对装配式组合结构的发展需求,提出了一种多层重力-侧力系统可分组合结构体系,通过梁端铰接实现了结构的竖向承重系统与水平抗侧力系统的分离,提升了装配式组合结构的标准化程度。根据该结构体系的布置方案,设计并完成了3个大比例体系试验,与传统刚接组合框架对比,分析了新型结构体系在竖向楼面荷载和水平滞回荷载作用下的力学性能,对两种结构体系开展了抗震性能评价。利用通用有限元软件MSC.Marc建立了新型结构体系的有限元模型,通过与试验结果对照分析了节点建模方式对计算结果的影响。研究结果表明,新型结构体系在水平地震作用下的安全裕度高于传统刚接组合框架,新型结构体系的节点表现出显著半刚性,其对结构竖向承载刚度和侧向刚度均有明显影响。 展开更多
关键词 重力-侧力系统可分组合结构体系 抗震性能评价 节点半刚性 试验研究 数值模拟
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国民经济核算体系的政治经济学研究
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作者 刘长新 《统计研究》 1987年第5期23-28,共6页
一建立一套具有中国特色的社会主义国民经济核算体系,满足党和政府加强国民经济管理,综合评估国民经济活动成效的需要,是统计工作的一项重要课题。一般说,国民经济核算体系是指由一整套科学的核算表所组成的、对国民经济活动的资源与条... 一建立一套具有中国特色的社会主义国民经济核算体系,满足党和政府加强国民经济管理,综合评估国民经济活动成效的需要,是统计工作的一项重要课题。一般说,国民经济核算体系是指由一整套科学的核算表所组成的、对国民经济活动的资源与条件、活动过程、活动的成果与效益进行总体性、平衡性核算的分组体系与指标体系的总称。它属于上层建筑范畴,受一定经济基础所制约,是在一定的科学理论基础上形成的。因此。 展开更多
关键词 国民经济核算体系 分组体系 社会再生产 物质资料再生产 劳动力再生产 马克思主义政治经济学 再生产过程 自然条件 基本要素 自然资源
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蜂窝网络的分组业务质量
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作者 张力军 《无线电工程》 2001年第4期12-16,27,共6页
该文主要介绍了GPRS网络的分组业务、QoS的属性和实现,指出了GPRS Qos能力的局限性问题。在此基础上,简要介绍了第三代蜂窝网分组QoS的体系,为网络中端到端的分组业务提供了可靠的QoS保障机制。
关键词 分组业务质量体系 蜂窝网络 移动通信 GPRS网
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装配式板柱钢结构体系建筑产业化技术与示范 被引量:10
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作者 赵鹤 王皓 +6 位作者 支旭东 张晓峰 李子昂 郑明召 严佳川 张立林 陶慕轩 《建筑钢结构进展》 CSCD 北大核心 2021年第10期32-43,共12页
针对我国装配式钢结构建筑推广应用过程中的标准化、模块化和产业化需求,提出了一种竖向承重体系和抗侧力体系相分离的新型组合结构体系,并基于这一概念提出了一系列适用于多层和高层住宅建筑的高性能结构方案。通过大比例试验、高效数... 针对我国装配式钢结构建筑推广应用过程中的标准化、模块化和产业化需求,提出了一种竖向承重体系和抗侧力体系相分离的新型组合结构体系,并基于这一概念提出了一系列适用于多层和高层住宅建筑的高性能结构方案。通过大比例试验、高效数值模拟和性能评价等方法对该种新型体系的抗震性能开展了深入研究,充分证明了其在地震区应用的可行性。另外,开展了与该新型结构体系相配套的集成式楼盖和一体化外围护墙板的研究,分别围绕集成式楼盖及节点的力学机理和一体化外围护墙板的保温性能、隔声性能、受弯性能以及与结构的协同受力性能展开了系列研究。目前,与装配式板柱钢结构体系相配套的一个示范产业园区和两条示范生产线均已建成,相关研发成果已成功应用在两项示范工程中,取得了良好的示范效果。 展开更多
关键词 重力-侧力系统可分组合结构体系 集成式楼盖 一体化外围护墙板 工程示范
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社会经济统计学原理辅导材料专辑
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《价格月刊》 1988年第2期43-48,共6页
关键词 综合指标 调查对象 分组体系 计算公式 简单算术平均数 相对指标 调和平均数 统计资料 统计研究 加权算术平均数
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港口工作组织
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《交通建设与管理》 1998年第12期40-41,共2页
关键词 工作组织 箱务管理 港口统计 分组体系 中国港口 集装箱码头 水运管理 翻车机 煤炭出口港 系统设计
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Synthesis of Multi-component Mass-exchange Networks 被引量:5
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作者 刘琳琳 都健 +2 位作者 Mahmoud M. EI-Halwagi Jose Maria Ponce-Ortega 姚平经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期376-381,共6页
This paper presents a superstructure-based formulation for the synthesis of mass-exchange networks (MENs) considering multiple components. The superstructure is simplified by directly using the mass separation agents ... This paper presents a superstructure-based formulation for the synthesis of mass-exchange networks (MENs) considering multiple components. The superstructure is simplified by directly using the mass separation agents (MSA) from their sources, and therefore the automatic synthesis of the multi-component system involved in the MENs can be achieved without choosing a 'key-component' either for the whole process or the mass exchangers. A mathematical model is proposed to carry out the optimization process. The concentrations, flow rates, matches and unit operation displayed in the obtained network constitute the exact representation of the mass exchange process in terms of all species in the system. An example is used to illustrate and demonstrate the application of the proposed method. 展开更多
关键词 multiple components mass exchange network SUPERSTRUCTURE OPTIMIZATION
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Layout problem of multi-component systems arising for improving maintainability 被引量:5
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作者 罗旭 杨拥民 +2 位作者 葛哲学 温熙森 官凤娇 《Journal of Central South University》 SCIE EI CAS 2014年第5期1833-1841,共9页
To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainabili... To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainability was analyzed, and the layout problem for maintainability was presented. It was formulated as an optimization problem, where maintainability, layout space and distance requirement were formulated as objective functions. A multi-objective particle swarm optimization algorithm, in which the constrained-domination relationship and the update strategy of the global best were simply modified, was then used to obtain Pareto optimal solutions for the maintainability layout design problem. Finally, application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method. The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability. 展开更多
关键词 MAINTAINABILITY layout problem OPTIMIZATION multi-component system multi-objective particle swarm optimization
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Operation of a Batch Stripping Distillation Column 被引量:7
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作者 许松林 JoseEspinosa +1 位作者 HectorE.Salomone OscarA.Iribarren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期141-144,共4页
A stripping batch distillation column is preferred when the amount of the light component in the feed is small and the products are to be recovered at high purity. The operation modes of a batch stripping are believed... A stripping batch distillation column is preferred when the amount of the light component in the feed is small and the products are to be recovered at high purity. The operation modes of a batch stripping are believed to be the same as those of a rectifier. However, the control system of a stripper is different. In this paper, we explore three different control methods with Hysys (Hyprotech Ltd. 1997) for a batch stripper. The main difference is the control scheme for reboiler liquid level: (a) controlled by reflux flow; (b) controlled by reboiler heat duty; (c) controlled by bottom product flow. The main characteristics of operating a batch stripper with different control scheme are presented in this paper. Guidelines are provided for the startup of a batch stripper, the effects of somecontrol tuning parameters on the column performance are discussed. 展开更多
关键词 batch stripper CONTROL operation
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The Applicability of the Density Rule of Pathwardhan and Kumer and the Rule Based on Linear Isopiestic Relation 被引量:1
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作者 胡玉峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期319-321,共3页
The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured val... The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured values for 18 electrolyte mixtures are compared. The two rules are good for mixtures with and without common ions, including those containing associating ions. The deviations of the rule based on the linear isopiestic relation are slightly higher for the mixtures involving very strong ion complexes, but the predictions are still quite satisfactory.The density rule of Pathwardhan and Kumer is more accurate for these mixtures. However, it is not applicable for mixtures containing non-electrolytes. The rule based on the linear isopiestic relation is extended to mixtures involving non-electrolytes. The predictions for the mixtures containing both electrolytes and non-electrolytes and the non-electrolyte mixtures are accurate. All these results indicate that this rule is a widely applicable approach. 展开更多
关键词 binary density rules DENSITY apparent molar volume multicomponent system binary sub-system
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Paleogeomorphy,provenance system and sedimentary system of the Dongying formation in the Qikou sag 被引量:5
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作者 WANG Hua HUANG Chuan-yan +6 位作者 ZHAO Shu-e YAN De-tian BAI Yun-feng XIANG Xue-mei CHEN Si XIA Cun-yin LIAO Ji-hua 《Mining Science and Technology》 EI CAS 2009年第6期800-806,共7页
Reconstructed synsedimentary paleogeomorpholgy is an effective method in predicting the distribution of sandbodies and can provide valid evidence in the search for reservoirs. Based on a synsedimentary paleogeomorphol... Reconstructed synsedimentary paleogeomorpholgy is an effective method in predicting the distribution of sandbodies and can provide valid evidence in the search for reservoirs. Based on a synsedimentary paleogeomorpholgy reconstruction of the third member of the Dongying formation (Ed3) in the Qikou sag,the basic paleogeomorphic characteristics of Ed3 are described and the spatial distributions of denudation and subsidence areas are discussed. Key boundary faults controlling the deposition of important sediment bodies are proposed and the interrelations among faulted slope-break belts or flexure belts,intra-depression uplifts and sags,sediment sources and sediments input points have been investigated. 展开更多
关键词 paleogeomorphology provenance system sedimentary system Dongying formation Qikou sag
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Sleeping of a Complex Brain Networks with Hierarchical Organization
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作者 ZHANG Ying-Yue YANG Qiu-Ying CHEN Tian-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期97-100,共4页
The dynamical behavior in the cortical brain network of macaque is studied by modeling each cortical area with a subnetwork of interacting excitable neurons. We characterize the system by studying how to perform the t... The dynamical behavior in the cortical brain network of macaque is studied by modeling each cortical area with a subnetwork of interacting excitable neurons. We characterize the system by studying how to perform the transition, which is now topology-dependent, from the active state to that with no activity. This could be a naive model for the wakening and sleeping of a brain-like system, i.e., a multi-component system with two different dynamical behavior. 展开更多
关键词 self-organized criticality hierarchical organization EEG-like wave cortical network SLEEPING
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A hybrid neural network system for prediction and recognition of promoter regions in human genome 被引量:1
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作者 陈传波 李滔 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第5期401-407,共7页
This paper proposes a high specificity and sensitivity algorithm called PromPredictor for recognizing promoter regions in the human genome. PromPredictor extracts compositional features and CpG islands information fro... This paper proposes a high specificity and sensitivity algorithm called PromPredictor for recognizing promoter regions in the human genome. PromPredictor extracts compositional features and CpG islands information from genomic sequence,feeding these features as input for a hybrid neural network system (HNN) and then applies the HNN for prediction. It combines a novel promoter recognition model, coding theory, feature selection and dimensionality reduction with machine learning algorithm.Evaluation on Human chromosome 22 was ~66% in sensitivity and ~48% in specificity. Comparison with two other systems revealed that our method had superior sensitivity and specificity in predicting promoter regions. PromPredictor is written in MATLAB and requires Matlab to run. PromPredictor is freely available at http://www.whtelecom.com/Prompredictor.htm. 展开更多
关键词 Hybrid neural network Promoter prediction Compositional features CpG islands
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The first complete mitogenome of Cyclommatus stag beetles(Coleoptera: Lucanidae) with the phylogenetic implications
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作者 刘静 李成功 +1 位作者 游硕 万霞 《Entomotaxonomia》 CSCD 2017年第4期294-299,共6页
The first complete mitogenome of Cyclommatus stag beetles, Cyclommatus vitalisi(Coleoptera: Lucanidae) is sequenced using the next generation sequening. The genomic structure is a closed circular molecule with 17,8... The first complete mitogenome of Cyclommatus stag beetles, Cyclommatus vitalisi(Coleoptera: Lucanidae) is sequenced using the next generation sequening. The genomic structure is a closed circular molecule with 17,853 bp in length, comprising 13 protein-coding genes, 22 transfer RNA genes(t RNAs), 2 ribosomal RNAs(r RNAs) and a control region. The sequence has neither a gene rearrangement nor a non-coding region. The nucleotide composition is A(36. 31%), C(21. 48%), T(31. 20%) and G(11. 01%), with overall AT content of 73. 61%. The phylogenetic analysis of 13 stag beetles and another three scarab beetles show that Cyclommatus vitalisi shares a close ancestry with Lucanus mazama and Lucanus fortunei. 展开更多
关键词 Cyclommatus vitalisi MITOGENOME phylogenomic analysis
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网络处理器的研讨
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作者 李甜娇 《神州》 2013年第23期49-49,共1页
网络处理器的应用研究被认为是推动下一代网络向高性能、灵活性方向发展的核心技术。本文从网络设备研制角度,对网络协议处理基本操作、网络处理器产生技术需求、基本功能、体系结构特点、产品现状、应用前景、未来发展进行研究。
关键词 关键词 网络处理器体系结构网络设备数据分组网络 协议网络高速发展
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The study of basic medical insurance system for urban residents in China
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作者 GU Yanfang ZHANG Yushuai 《International English Education Research》 2017年第4期60-62,共3页
The basic medical insurance system for urban residents is an important part of China's social security system.This article analyzes the problems which existing in the basic medical insurance system for urban resident... The basic medical insurance system for urban residents is an important part of China's social security system.This article analyzes the problems which existing in the basic medical insurance system for urban residents and puts forward the corresponding countermeasures. 展开更多
关键词 Social security system RESIDENTS Medical insurance
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Electrical conductivities for four ternary electrolyte aqueous solutions with one or two ionic liquid components at ambient temperatures and pressure
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作者 梁倩卿 胡玉峰 岳文佳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第6期873-879,共7页
This work provides a method to explore the transport property of the electrolyte aqueous solutions with one or two ionic liquids, especially focus on their electrical conductivity. The conductivities were measured for... This work provides a method to explore the transport property of the electrolyte aqueous solutions with one or two ionic liquids, especially focus on their electrical conductivity. The conductivities were measured for the ternary systems Na Cl–[C6mim][Cl](1-hexyl-3-methylimidazolium chloride)–H2O, [C6mim][BF4]–[C6mim][Cl]–H2O,Na NO3–[C6mim][BF4](1-hexyl-3-methylimidazolium tetrafluoroborate)–H2O, and [C4mim][BF4](1-butyl-3-methylimidazolium tetrafluoroborate)–[C6mim][BF4]–H2O, and their binary subsystems NaN O3–H2O, NaC l–H2O,[C6mim][BF4]–H2O, [C6mim][Cl]–H2O, and [C4mim][BF4]–H2O, respectively. The conductivities of the ternary systems were also determined using generalized Young's rule and semi-ideal solution theory in terms of the data of their binary solutions. The comparison showed that the two simple equations provide good predictions for conductivity of mixed electrolyte solutions and the mixed ionic liquid solutions based on the conductivity of their binary subsystems. 展开更多
关键词 CONDUCTIVITY Young's rule Semi-ideal solution theory Binary system Ternary system
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Management of University Intellectual Property Problems and Countermeasures
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作者 Fujing HUANG 《International Journal of Technology Management》 2015年第1期53-55,共3页
university intellectual property management mechanism is a planned university intellectual property organization, coordination, planning and use of standardized management system. Sound intellectual property managemen... university intellectual property management mechanism is a planned university intellectual property organization, coordination, planning and use of standardized management system. Sound intellectual property management mechanism is the key to the implementation of university intellectual property strategy, and working intellectual property smoothly, also it is a vital part to establish a modem university management system. This article discussed and analyzed about intellectual property rights managements mechanism universities setting the organization, regulations, incentives and policies to protect five aspects of education which combined with domestic and foreign universities intellectual property management practices. 展开更多
关键词 UNIVERSITY intellectual property management mechanism
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竖向承重与水平抗侧相分离的组合框架-剪力墙结构体系抗震性能研究 被引量:9
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作者 李子昂 许立言 陶慕轩 《建筑结构学报》 EI CAS CSCD 北大核心 2021年第2期15-26,共12页
为提高传统钢结构体系在住宅产业化应用中的标准化程度、装配化效率以及安全性能,提出了竖向承重与水平抗侧相分离的组合框架-剪力墙结构体系,并对其抗震性能进行了分析与评价。以某高层住宅楼工程为结构方案原型,基于多遇地震作用下弹... 为提高传统钢结构体系在住宅产业化应用中的标准化程度、装配化效率以及安全性能,提出了竖向承重与水平抗侧相分离的组合框架-剪力墙结构体系,并对其抗震性能进行了分析与评价。以某高层住宅楼工程为结构方案原型,基于多遇地震作用下弹性层间位移角相同的控制标准,分别按传统组合框架-剪力墙结构体系和按竖向承重与水平抗侧相分离的组合框架-剪力墙结构体系设计了两种结构方案,并建立了相应的有限元模型。采用静力弹塑性推覆方法,对两种体系在设防地震和罕遇地震作用下的变形和受力特征进行了对比分析,通过结构层间变形、关键构件损伤状态以及安全系数等指标对体系抗震性能进行了综合评估。分析结果表明:竖向承重与水平抗侧相分离的组合框架-剪力墙结构体系在地震作用下的侧移模式呈弯曲型,推覆过程中结构塑性铰主要出现在底层柱端,而传统组合框架-剪力墙结构体系侧移模式呈弯剪型,塑性铰主要出现在梁端;选取的两种剪力墙损伤判断标准均可用于准确判断两种结构方案的极限状态;在相同弹性层间位移角控制标准下,竖向承重与水平抗侧相分离的组合结构体系设计方案安全系数指标值更高,在地震作用下具备更高安全储备。 展开更多
关键词 分组合结构体系 静力推覆分析 结构损伤评估 安全系数 抗震性能评价
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