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Trust Model Based on Structured Protection for High Level Security System 被引量:1
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作者 Liao Jianhua Zhao Yong Zhan Jing 《China Communications》 SCIE CSCD 2012年第11期70-77,共8页
In order to ensure the security of information systems, it's essential to make sure that system behaviors are trusted. By analyzing threats that exist in executing procedures, a trust model based on structured pro... In order to ensure the security of information systems, it's essential to make sure that system behaviors are trusted. By analyzing threats that exist in executing procedures, a trust model based on structured protection is proposed. We consider that functional components, system actions and message flows between components are three key factors of information systems. Structured protection requirements on components, connections and action parameters are also provided. Four trusted properties of the model are deducted through formal analysis, and trusted system behavior is defined based on these properties. Furthermore, decision theorem of trusted system behavior is proved. The developed prototype system indicates the model is practical. It is a general theory model built on logic deduction and independent on specific environment and the behaviors of the system designed and implemented following the model are trusted. 展开更多
关键词 trusted computing security assurance structured protection
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Fault detection of large-scale process control system with higher-order statistical and interpretative structural model 被引量:1
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作者 耿志强 杨科 +1 位作者 韩永明 顾祥柏 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期146-153,共8页
Nonlinear characteristic fault detection and diagnosis method based on higher-order statistical(HOS) is an effective data-driven method, but the calculation costs much for a large-scale process control system. An HOS-... Nonlinear characteristic fault detection and diagnosis method based on higher-order statistical(HOS) is an effective data-driven method, but the calculation costs much for a large-scale process control system. An HOS-ISM fault diagnosis framework combining interpretative structural model(ISM) and HOS is proposed:(1) the adjacency matrix is determined by partial correlation coefficient;(2) the modified adjacency matrix is defined by directed graph with prior knowledge of process piping and instrument diagram;(3) interpretative structural for large-scale process control system is built by this ISM method; and(4) non-Gaussianity index, nonlinearity index, and total nonlinearity index are calculated dynamically based on interpretative structural to effectively eliminate uncertainty of the nonlinear characteristic diagnostic method with reasonable sampling period and data window. The proposed HOS-ISM fault diagnosis framework is verified by the Tennessee Eastman process and presents improvement for highly non-linear characteristic for selected fault cases. 展开更多
关键词 High order statistics Nonlinear characteristics diagnosis Interpretative structural model TE process
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Involvement of XZFP36L1, an RNA-binding protein, in Xenopus neural development '
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作者 Yingjie XIA Shuhua ZHAO Bingyu MAO 《Zoological Research》 CAS CSCD 北大核心 2012年第6期I0020-I0026,共7页
Xenopus ZFP36L1 (zinc finger protein 36, C3H type-like 1) belongs to the ZFP36 family of RNA-binding proteins, which contains two characteristic tandem CCCH-type zinc-finger domains. The ZFP36 proteins can bind AU-r... Xenopus ZFP36L1 (zinc finger protein 36, C3H type-like 1) belongs to the ZFP36 family of RNA-binding proteins, which contains two characteristic tandem CCCH-type zinc-finger domains. The ZFP36 proteins can bind AU-rich elements in 3' untranslated regions of target mRNAs and promote their turnover. However, the expression and role of ZFP36 genes during neural development in Xenopus embryos remains largely unknown. The present study showed that Xenopus ZFP36L1 was expressed at the dorsal part of the forebrain, forebrain-midbrain boundary, and midbrain-hindbrain boundary from late neurula stages to tadpole stages of embryonic development. Overexpression of XZFP36L1 in Xenopus embryos inhibited neural induction and differentiation, leading to severe neural tube defects. The function of XZP36L1 requires both its zinc finger and C terminal domains, which also affect its subcellular localization. These results suggest that XZFP36L1 is likely involved in neural development in Xenopus and might play an important role in post-transcriptional regulation. 展开更多
关键词 ZFP36L1 RNA-binding protein Neural development XENOPUS Post-transcriptional regulation
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Shed Light on the Geometrical Configuration and Structural Principle of an Ancient Wooden Bridge in Qingming Shanghe Tu
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作者 Pei-Shan Chen 《Journal of Civil Engineering and Architecture》 2012年第6期665-672,共8页
In the centre of the famous Chinese painting, Qingrning Shanghe Tu, an arch-shaped timber bridge, Hongqiao, stands like a rainbow over the river Bianhe. Unfortunately, Hongqiao was damaged during floods from the Yello... In the centre of the famous Chinese painting, Qingrning Shanghe Tu, an arch-shaped timber bridge, Hongqiao, stands like a rainbow over the river Bianhe. Unfortunately, Hongqiao was damaged during floods from the Yellow River, and we can only see her beautiful form in Qingming Shanghe Tu. While, the geometrical dimensions, structural principle, as well as the construction methods of the bridge are still an interesting mystery. In the present paper, the author uncovers the structural principle and the geometric dimensions of the bridge as well as its history background. Furthermore, the author introduces two new structural systems, Lap-Beam and 1.5-Layer space frame, which are inspired by the structural principle of the Hongqiao. 展开更多
关键词 Lap-beam 1.5-layer space frame arch bridge Hongqiao Qingming Shanghe Tu wooden bridge.
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An agent-based service-oriented integration architecture for chemical process automation
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作者 罗娜 钟伟民 +2 位作者 万锋 叶贞成 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期173-180,共8页
In reality, traditional process control system built upon centralized and hierarchical structures presents a weak response to change and is easy to shut down by single failure. Aiming at these problems, a new agent-ba... In reality, traditional process control system built upon centralized and hierarchical structures presents a weak response to change and is easy to shut down by single failure. Aiming at these problems, a new agent-based service-oriented integration architecture was proposed for chemical process automation system. Web services were dynamically orchestrated on the internet and agent behaviors were built in them. Data analysis, model, optimization, control, fault diagnosis and so on were capsuled into different web services. Agents were used for service compositions by negotiation. A prototype system of poly(ethylene terephthalate) process automation was used as the case study to demonstrate the validation of the integration. 展开更多
关键词 Automation system Integration Web services Service-oriented architecture AGENT
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Reconfiguration in the Transmission System of the Slovak Republic
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作者 Juraj Altus Martin Jedinak +1 位作者 Stanislav Prielozny Rastislav Smidovic 《Journal of Energy and Power Engineering》 2013年第3期577-582,共6页
Topology changes (reconfigurations) in the transmission system are effective remedial actions to restore fulfilling N-I security principle. In the transmission system, Slovak Republic prepares several scenarios of p... Topology changes (reconfigurations) in the transmission system are effective remedial actions to restore fulfilling N-I security principle. In the transmission system, Slovak Republic prepares several scenarios of possible reconfigurations, especially in the substation Varin and substation Lemesany. The paper describes reasons of reconfiguration necessity, preparation process, testing process, test results and comparison with expected results from simulation calculations. The conclusion summarizes advantages and disadvantages of the reconfiguration implementation in the transmission system, recommendations for real-time operation, including coordination with neighbouring transmission system operators and affected distribution system operators. 展开更多
关键词 Real-time operation operational limits N-1 security principle remedial actions topology change.
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工程项目组织变迁框架研究
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作者 林基础 成虎 《建筑经济》 2010年第4期80-83,共4页
随着工程项目建设的开展,各种参与组织加入或退出工程项目组织系统,因而在工程项目全寿命期内存在工程项目组织的变迁。工程项目组织变迁的研究须结合工程项目及其组织的特殊性。以工程项目组织及其变迁的特性为立足点,给出工程项目组... 随着工程项目建设的开展,各种参与组织加入或退出工程项目组织系统,因而在工程项目全寿命期内存在工程项目组织的变迁。工程项目组织变迁的研究须结合工程项目及其组织的特殊性。以工程项目组织及其变迁的特性为立足点,给出工程项目组织变迁的定义,并阐述其系统结构过程、变迁形式、一般机理、内外环境分析及特点。 展开更多
关键词 工程项目组织 组织变迁 系统结构过程 变迁机理 内外环境分析
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Structure for energy cycle: a unique status of the second law of thermodynamics for living systems 被引量:1
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作者 Shunong Bai Hao Ge Hong Qian 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第10期1266-1273,共8页
Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the... Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the earliest "live" process is embedded essentially in a special interaction between a pair of specific components under a particular, corresponding environmental conditions. The interaction exists as an inter-molecular-force-bond complex(IMFBC) that couples two separate chemical processes: one is the spontaneous formation of the IMFBC driven by a decrease of Gibbs free energy as a dissipative process; while the other is the disassembly of the IMFBC driven thermodynamically by free energy input from the environment. The two chemical processes coupled by the IMFBC originated independently and were considered non-living on Earth, but the IMFBC coupling of the two can be considered as the earliest form of metabolism: the first landmark on the path from things to a being. The dynamic formation and disassembly of the IMFBC, as a composite individual, follows a principle designated as "… structure for energy for structure for energy…", the cycle continues; and for short it will be referred to as "structure for energy cycle". With additional features derived from this starting point, the IMFBC-centered "live" process spontaneously evolved into more complex living organisms with the characteristics currently known. 展开更多
关键词 structure energy living systems IMFBC CYCLE
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Application of Ordinary Kriging in Mapping Soil Organic Carbon in Zambia 被引量:7
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作者 Lydia Mumbi CHABALA Augustine MULOLWA Obed LUNGU 《Pedosphere》 SCIE CAS CSCD 2017年第2期338-343,共6页
The quantification of the pattern and spatial distribution of soil organic carbon (SOC) is fundamental to understand many ecosystem processes. This study aimed to apply ordinary kriging (OK) to model the spatial d... The quantification of the pattern and spatial distribution of soil organic carbon (SOC) is fundamental to understand many ecosystem processes. This study aimed to apply ordinary kriging (OK) to model the spatial distribution of SOC in a selected part of Zambia. A total of 100 soil samples were collected from the study area and analyzed for SOC by determining soil oxidizable carbon using the Walkley-Black method. An automated fitting procedure was followed when modeling the spatial structure of the SOC data with the exponential semivariogram. The results indicated that the short range spatial dependence of SOC was strong with a nugget close to zero. The spatial autocorrelation was high to medium with a nugget to sill ratio of 0.25. The root mean square error of the predictions was 0.64, which represented 58.18% of the mean observed data for SOC. It can be concluded that the generated map could serve as a proxy for SOC in the region where evidence of spatial structure and quantitative estimates of uncertainty are reported. Therefore, the maps produced can be used as guides for various uses including optimization of soil sarapling. 展开更多
关键词 exponential semivariogram geographical distribution geostatistical procedure oxidizable carbon spatial autocorrela-tion
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Comparison of the topologies for a hybrid energy-storage system of electric vehicles via a novel optimization method 被引量:1
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作者 ZHANG Shuo XIONG Rui ZHOU Xuan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第7期1173-1185,共13页
The combination of batteries and ultracapacitors has become an effective solution to satisfy the requirements of high power density and high energy density for the energy-storage system of electric vehicles.Three aspe... The combination of batteries and ultracapacitors has become an effective solution to satisfy the requirements of high power density and high energy density for the energy-storage system of electric vehicles.Three aspects of such combination efforts were considered for evaluating the four types of hybrid energy-storage system(HESS)topologies.First,a novel optimization framework was proposed and implemented to optimize the voltage level of a battery pack and an ultracapacitor pack for the four types of HESS topologies.During the optimization process,the dynamic programming(DP)algorithm was iteratively applied to determine the optimal control actions.The simulation results with DP were used to evaluate the energy efficiency of different HESS topologies at different voltage levels.Second,the optimized voltage level of the battery and ultracapacitor in each topology indicates that a higher voltage level usually results in a better system performance.The simulation results also illustrate that the optimized rated voltage level of the battery pack is approximately 499.5 V,while for the ultracapacitor pack,the optimized voltage level is at its maximum allowed value.Note that the constraint of the battery voltage is initialized at200–600 V.Third,the control rules for different HESS topologies were obtained through the systematic analysis of the simulation results.In addition,advantages and disadvantages of the four topologies were summarized through evaluation of the efficiency and operating currents of the batteries and the ultracapacitor. 展开更多
关键词 electric vehicles lithium-ion battery ULTRACAPACITOR hybrid energy-storage system TOPOLOGY dynamic programming
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Thick SU8 microstructures prepared by broadband UV lithography and the applications in MEMS devices
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作者 李东玲 温志渝 +1 位作者 尚正国 佘引 《Optoelectronics Letters》 EI 2016年第3期182-187,共6页
Thick SU8 microstructures with high aspect ratio and good side wall quality were fabricated by ultraviolet (UV) lithography, and the processing parameters were comprehensively studied. It proves that the adhesion of... Thick SU8 microstructures with high aspect ratio and good side wall quality were fabricated by ultraviolet (UV) lithography, and the processing parameters were comprehensively studied. It proves that the adhesion of SU8 on silicon (Si) substrates is influenced by Si-OH on the surface, and can be improved by the HF treatment. Cracks and de- lamination are caused by large internal stress during fabrication process, and are significantly influenced by soft bake and post-exposure bake processes. The internal stress is reduced by a low post-exposure bake exposure tem- perature of 85 ℃ for 40 rain. A three-step soft bake enhances the reflowing ofSU8 photoresist, and results in uni- form surface and less air bubbles. The vertical side wall is obtained with the optimized exposure dose of 800 mJ/cm2 for the thickness of 160 μm. Using the optimized fabrication process combined with a proper structure design, dense SU8 micro pillars are achieved with the aspect ratio of 10 and the taper angle of 89.86°. Finally, some possible ap- plications of SU8 in micro-electromechanical system (MEMS) device are developed and demonstrated. 展开更多
关键词 MEMS器件 紫外光刻 结构 应用 微机电系统 烘烤过程 编写 宽带
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