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云模型 2

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The investigation of pressure drop in moving-beds

CHEN Yunhua, ZHU Xuedong, WU Yongqiang, ZHU Zibin

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 184-189 doi: 10.1007/s11705-007-0034-4

摘要： The pressure drop of a cross-flow moving-bed was investigated in a two-dimensional rectangular apparatus. The effects of the particle velocity, the superficial gas velocity, the formation and development of cavity/raceway and voidage of particles on the pressure drop were investigated experimentally under the operational conditions of 0.09 1.35 m/s of the superficial gas velocity and 0.95 9.68 cm/min of the particle velocity. The experimental results show that the particle velocity has little influence on the pressure drop, while the phenomena of cavity and pinning occur when the cross-flow velocity is high enough. The development of a cavity or a raceway can result in three types of variations of pressure drop with time: stabilization, slight fluctuation and severe fluctuation. A cavity appears in a process cycle of formation-growing up-collapsing-fluidization at a high gas velocity. On the basis of experimental results, a model for calculating the pressure drop after a cavity occurs and a dimensionless relationship of cavity size is developed, which gives a good qualitative account of the experimental data.

关键词： development cross-flow velocity superficial qualitative account stabilization

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运用自组织竞争网络进行气体定性分析的研究

太惠玲,谢光忠,蒋亚东

《中国工程科学》 2006年第8卷第1期页码 81-84

摘要：

优选了分析H₂，CO气体的半导体气体传感器组成阵列，建立了实时数据采集系统，并与自组织竞争网络模式识别技术相结合，以进行气体定性分析的研究；同时为了消除气体浓度变化对传感器阵列输出的影响，提高自组织网络的识别效果，运用三种不同的数据归一化算法对传感器阵列的输出响应进行了预处理，并对各自对应的网络识别结果进行了分析与讨论。实验结果表明，采用相对算法可实现H₂，CO气体的准确识别。

关键词：气体传感器阵列自组织竞争网络定性分析

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Qualitative analysis of direction of public hospital reforms in China

null

《医学前沿（英文）》 2018年第12卷第2期页码 218-223 doi: 10.1007/s11684-017-0534-7

摘要：

Reforms in public hospitals are among the most important improvements in China’s health care system over the last two decades. However, the reforms that should be implemented in public hospitals are unclear. Thus, a feasible direction of reforms in Chinese public hospitals is suggested and reliable policy suggestions are provided for the government to reform public hospitals. The data used in this study were mainly derived from a qualitative study. Focus group discussions and in-depth interviews were conducted in Shanghai, Guangdong, and Gansu between May and December 2014. Government funding accounted for approximately eight percent of the total annual revenue of public hospitals in China, and the insufficient government subsidy considerably affects the operation mechanism of public hospitals. However, solely increasing this subsidy cannot address the inappropriate incentives of public hospitals in China. The most crucial step in setting the direction of reforms in public hospitals in China is transforming inappropriate incentives by implementing a new evaluation index system for directors and physicians in public hospitals.

关键词： public hospital government hospital public funding operation mechanism

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知识表示中的不确定性

李德毅

《中国工程科学》 2000年第2卷第10期页码 73-79

摘要：

知识表示一直是人工智能研究中的一个瓶颈，其难点在于知识中隐含有不确定性，即模糊性和随机性。文章提出用云模型3个数字特征（期望值，熵，超熵）来描述一个定性概念，用熵来关联模糊性和随机性。代表定性概念的云的某一次定量值，被称为云滴，可以用它对此概念的贡献度来衡量，许许多多云滴构成云，实现定性和定量之间的随时转换，反映了知识表示中的不确定性。论文以此对我国农历24个节气进行了新的量化解释。云方法已经用于数据开采、智能控制、跳频电台和大系统效能评估中，取得明显的效果。

关键词：知识表示定性概念不确定性云模型数宇特征

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Theoretical analysis and experimental study on the influence of electric double layer on thin film lubrication

WANG Xin-jie, BAI Shao-xian, HUANG Ping

《机械工程前沿（英文）》 2006年第1卷第3期页码 370-373 doi: 10.1007/s11465-006-0040-0

摘要： A new mathematical model for thin film lubrication is established by taking into account the effect of an electric double layer. In the present paper, experiments are carried out on a self-made tester. With a composite block and a

关键词： mathematical account electric composite lubrication

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三级倒立摆的云控制方法及动平衡模式

李德毅

《中国工程科学》 1999年第1卷第2期页码 41-46

摘要：

文章提出了定性和定量之间转换的云模型的形式化表示方法，用来反映语言值中蕴涵的模糊性和随机性，给出云发生器的生成算法，解释多条定性推理规则同时被激活时的不确定性推理机制。利用这种智能控制方法有效地实现了单电机控制的一、二、三级倒立摆的多种不同动平衡姿态，显示其鲁棒性，并给出了详细试验结果。研究成果不仅可用于对太空飞行器以及机器人控制，而且对揭示定性定量转换规律和策略具有普遍意义。

关键词：智能控制云模型定性推理倒立摆

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区域水资源可持续利用评价理论模型与方法

陈守煜

《中国工程科学》 2001年第3卷第2期页码 33-38

摘要：

文章在论述区域水资源可持续利用与水资源承载能力关系的前提下，提出了区域水资源可持续利用评价的模糊模式识别理论、模型和方法。应用所建立的模型对汉中盆地水资源可持续利用的程度进行了评价，应用实例表明，理论模型严谨，方法简洁，评价结果合理可行。此方法也可用于区域社会经济可持续发展等的评价。

关键词：水资源可持续利用评价模式识别模糊性

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我国生态文明统计核算方法研究

石庆焱,周晶

《中国工程科学》 2017年第19卷第4期页码 67-73 doi: 10.15302/J-SSCAE-2017.04.011

摘要：

构建生态文明统计核算体系是生态文明建设的基础性工作，可为生态文明建设进程的监测、评估和决策提供可靠的数据支撑。虽然我国目前已有一定的资源环境统计基础，但由于缺少生态文明统计核算的顶层设计，因此无法将这些数据有效整合于统一框架。本文从生态文明建设的实际需求出发，分析了我国在生态文明统计核算中存在的问题，在结合SEEA2012–CF的基础上构建了我国生态文明统计指标体系和核算框架，并就进一步完善我国生态文明统计核算体系提出建议。

关键词：生态文明 SEEA2012–CF 统计体系核算框架自然资源资产负债表环境资产账户

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Post-evaluation of a water pollution control plan: methodology and case study

Lin ZENG,Xin DONG,Siyu ZENG,Tianzhu ZHANG,Jing LI,Jining CHEN

《环境科学与工程前沿（英文）》 2015年第9卷第4期页码 712-724 doi: 10.1007/s11783-015-0773-2

摘要： China has developed more than 20 water pollution control plans for river basins (RBWPs) since 1996. However, the implementation has generally lagged. This paper proposes a three-step, post-evaluation methodology to analyze the implementation result of a RBWP and its influential factors. First, a multi-attribute evaluation method based on an index system is established to score the enforcement results of a RBWP. Indicators measure how well a RBWP has achieved its objectives, which include water quality compliance, pollution load control, project construction, financial inputs, and related management requirements. Second, an interpretive structural model is used to detect the significant factors that affect RBWP implementation. This model can effectively analyze the cause-effect chain and hierarchical relationship among variables. Five groups of factors were identified, namely, plan preparation, water resource endowment, policy, institution, and management. Both qualitative and quantitative methods are employed in the third step to evaluate the extent to which these factors have influenced the execution result of a RBWP, including pre-post contrast, scenario analysis, and correlation analysis. This research then post-evaluated the implementation of the Huai River Basin water pollution control plans (H-RBWPs) over a period of 10 years as a case study. Results showed that the implementation of the H-RBWPs was unsatisfactory during 2001–2005, although it improved during 2006–2010. The poor execution of these plans was partially caused by the underestimation of regional economic development in combination with ineffective industrial structure adjustment policies. Therefore, this case study demonstrates the feasibility and flexibility of the proposed post-evaluation methodology.

关键词： river basin water pollution control plan post plan evaluation multi-attribute comprehensive evaluation interpretive structural model combined qualitative/quantitative method