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用于有限元分析的一种新的等级基多重网格法 被引量:2
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作者 程军峰 徐善驾 《电子学报》 EI CAS CSCD 北大核心 2003年第9期1303-1306,共4页
本文利用自适应有限元剖分和等级基技术 ,提出了一种新的等级基多重网格的分析方法 .由于该方法的限制算子R具有十分简单的表达形式 ,使得新方法的算法非常简单 。
关键词 多重网格 自适应加密 等级基
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完全安全的等级身份基在线/离线加密 被引量:2
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作者 王占君 马海英 王金华 《计算机应用》 CSCD 北大核心 2015年第9期2522-2526,2534,共6页
针对现有等级身份基加密(HIBE)中的加密算法很难适用于轻量级设备的问题,提出一种完全安全的等级身份基在线/离线加密机制。该机制将在线/离线密码技术引入到等级身份基加密中,其加密算法被分解成离线和在线两个加密算法。离线加密算法... 针对现有等级身份基加密(HIBE)中的加密算法很难适用于轻量级设备的问题,提出一种完全安全的等级身份基在线/离线加密机制。该机制将在线/离线密码技术引入到等级身份基加密中,其加密算法被分解成离线和在线两个加密算法。离线加密算法在不知道明文和接收者身份的前提下,对加密所需的幂乘等复杂计算进行预处理,使得在线加密算法一旦获知消息和接收者身份,仅需执行少量简单计算即可生成密文。实验结果表明,该机制极大地提高了HIBE的加密效率,非常适用于轻量级设备,并证明其具有完全安全性。 展开更多
关键词 在线/离线加密 等级身份加密 完全安全性 轻量级设备
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土工合成材料在公路软基处理中的应用与设计 被引量:26
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作者 郭大华 《土木工程学报》 EI CSCD 北大核心 2001年第3期84-89,共6页
结合《公路软土地基路堤设计与施工技术规范》和《公路土工合成材料应用技术规范》的规定 ,对土工合成材料在高等级公路软基处理中的应用设计中应注意的几个问题进行了初步探讨 ,同时对相关规范的理解和执行提出了建议。
关键词 土工合成材料 等级公路软 设计方法
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非防洪功能泡沼蓄洪风险识别与评估 被引量:3
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作者 许士国 王雪妮 刘建卫 《水电能源科学》 北大核心 2010年第9期44-47,共4页
针对洪水具有资源和灾害双重属性且洪水资源利用过程中的风险研究必不可少,在分析平原地区泡沼蓄洪利用过程的基础上,对泡沼蓄洪的主要风险因子进行了识别,建立了二维泡沼蓄洪风险估算模型,并以白城市茨勒泡在7、8月间的蓄洪为例,计算... 针对洪水具有资源和灾害双重属性且洪水资源利用过程中的风险研究必不可少,在分析平原地区泡沼蓄洪利用过程的基础上,对泡沼蓄洪的主要风险因子进行了识别,建立了二维泡沼蓄洪风险估算模型,并以白城市茨勒泡在7、8月间的蓄洪为例,计算了不同蓄洪量所对应的风险率。结果表明,茨勒泡在7、8月间蓄洪风险的等级基本上为轻险。为制定泡沼在适宜时机引蓄适当洪量提供了理论依据。 展开更多
关键词 防洪功能 蓄洪量 风险识别 水资源利用过程 双重属性 平原地区 理论依据 估算模型 风险因子 风险研究 风险率 等级基 白城市 灾害 水具 结果 计算 分析 二维
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IFC implementation in lifecycle costing 被引量:7
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作者 Charlie Fu Ghassan Aouad +2 位作者 Amanda Marshall Ponting Angela Lee Song Wu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期437-441,共5页
Life Cycle Costing (LCC) is always a major concern in the Architecture, Engineering and Construction (AEC) industry. This paper presents the implementation of Building Information Modeling (BIM) technology in the deve... Life Cycle Costing (LCC) is always a major concern in the Architecture, Engineering and Construction (AEC) industry. This paper presents the implementation of Building Information Modeling (BIM) technology in the development of a lifecycle cost-estimating tool. The IFC (Industry Foundation Classes) model as an interoperable building information model has been adopted as the central data repository to deliver the integrated information of building designs from CAD design systems into the lifecycle-costing database. In this paper, the conceptions and relevant factors, which could affect the LCC estimation, have been introduced. The problems of current LCC applications have been identified as the lack of LCC data and the complexity of LCC exercises. The software application of IFC models and relevant auxiliary are depicted as a solution of the problem identified. The lifecycle costing tool is a part of the nD Modeling tool and as such is based on its integrated interface prototype toolkit and is able to holistically present an IFC model into a 3D virtual reality view, a tree-view and a list of element properties. The functions and some technical points are also detailed in the paper. Through the research, it demonstrates the potential and possibility of implementing BIM methods and techniques, particularly IFCs to enhance the computer applications in the processes of building construction and facility management. 展开更多
关键词 AEC industry life cycle costing building information modeling industry foundation classes
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Calculation of Maximum Allowable Free Span Length and Safety Assessment of the DF1-1 Submarine Pipeline 被引量:4
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作者 XU Jishang LI Guangxue +2 位作者 Juan J. Horrillo YANG Rongmin CAO Lihua 《Journal of Ocean University of China》 SCIE CAS 2010年第1期1-10,共10页
The DFI-1 submarine pipeline was investigated using a dual-frequency side-scan sonar and a swath sounder system. More than a hundred scour pits under the pipeline were found, most of which have caused the span of the ... The DFI-1 submarine pipeline was investigated using a dual-frequency side-scan sonar and a swath sounder system. More than a hundred scour pits under the pipeline were found, most of which have caused the span of the pipeline to increase and threatened its safety. The maximum allowable free span length (MAFSL) of the pipeline was determined through the limitations re- garding maximum allowable stress under static or quasi-static loads and the onset of Vortex Induced Vibrations (VIV) under different hydrodynamic actions. The results show that the MAFSL under static conditions is 56m. However, the MAFSLs are 30m and 20m under ordinary weather conditions and hurricane-induced currents for the 100-year return period, respectively, to avoid VIV as cal- culated by using the highest safety class factor. It is suggested that spanning pipelines longer than 20 m should be supported. Addi- tionally, eight successive spans which may also threaten the pipeline were proposed. The most hazardous scour pits are along the pipeline section from KP42 to KP51. 展开更多
关键词 submarine pipeline SCOUR SPAN safety assessment Vortex Induced Vibrations (VIV) maximum allowable span length
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Discriminant Analysis on Land Grading
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作者 LIUYaolin HOUYajuan 《Geo-Spatial Information Science》 2004年第2期104-107,共4页
This paper proposes the discriminant analysis on land grading after analyzing the common methods and discussing the Fisher’s discriminant in detail. Actually this method deduces the dimension from multi to single, th... This paper proposes the discriminant analysis on land grading after analyzing the common methods and discussing the Fisher’s discriminant in detail. Actually this method deduces the dimension from multi to single, thus it makes the feature vectors in n \|dimension change to a scalar, and use this scalar to classify samples. This paper illustrates the result by giving an example of the residential land grading by the discriminant analysis. 展开更多
关键词 land grading discriminant analysis fisher's discriminant
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Studies of Differentially-Expressed Genes in Human Endometrial Cancer of Various Differentiated Grades
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作者 Bin Cai David Hogg +6 位作者 Guangzhong Lu Ling Liu Xiaowei Xi Wei Xu Huifang Lu Yongbin Yang Xiaoping Wan 《Chinese Journal of Clinical Oncology》 CSCD 2007年第2期77-82,共6页
OBJECTIVE To study the gene expression profiles of human endometrial cancers at various differentia0ted grade levels and to identify the genes related to differentiation of the endometrial cancers. METHODS cDNA microa... OBJECTIVE To study the gene expression profiles of human endometrial cancers at various differentia0ted grade levels and to identify the genes related to differentiation of the endometrial cancers. METHODS cDNA microarray technology was used to analyze the differentially-expressed genes among different differentiated grades of 32 cases of endometrial cancer. Hierarchical cluster analysis (HCA) for the gene expression profiles of the cases was employed. RESULTS The tissue samples were grouped based on the various differentiated tumor grades with 33 differentiation-related genes identified out (P〈0.001). Based on the results from the HCA, the conformity rate was 91% among the 33 differentially-expressed genes, and the analysis of pathological classification.CONCLUSION Genes related to the differentiation of endometrial cancer can be identified by using gene chips to analyze the expression profiles of endometrial cancers at various differentiated grades; HCA of the gene expression profiles can be helpful for distinguishing high-risk endometrial cancers before surgery. 展开更多
关键词 cDNA microarray endometrial tumor gene expression profile hierarchical cluster analysis.
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Recovery and grade prediction of pilot plant flotation column concentrate by a hybrid neural genetic algorithm 被引量:6
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作者 F. Nakhaei M.R. Mosavi A. Sam 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期69-77,共9页
Today flotation column has become an acceptable means of froth flotation for a fairly broad range of applications, in particular the cleaning of sulfides. Even after having been used for several years in mineral proce... Today flotation column has become an acceptable means of froth flotation for a fairly broad range of applications, in particular the cleaning of sulfides. Even after having been used for several years in mineral processing plants, the full potential of the flotation column process is still not fully exploited. There is no prediction of process performance for the complete use of available control capabilities. The on-line estimation of grade usually requires a significant amount of work in maintenance and calibration of on-stream analyzers, in order to maintain good accuracy and high availability. These difficulties and the high cost of investment and maintenance of these devices have encouraged the approach of prediction of metal grade and recovery. In this paper, a new approach has been proposed for metallurgical performance prediction in flotation columns using Artificial Neural Network (ANN). Despite of the wide range of applications and flexibility of NNs, there is still no general framework or procedure through which the appropriate network for a specific task can be designed. Design and structural optimization of NNs is still strongly dependent upon the designer's experience. To mitigate this problem, a new method for the auto-design of NNs was used, based on Genetic Algorithm (GA). The new proposed method was evaluated by a case study in pilot plant flotation column at Sarcheshmeh copper plant. The chemical reagents dosage, froth height, air, wash water flow rates, gas holdup, Cu grade in the rougher feed, flotation column feed, column tail and final concentrate streams were used to the simulation by GANN. In this work, multi-layer NNs with Back Propagation (BP) algorithm with 8-17-10-2 and 8- 13-6-2 arrangements have been applied to predict the Cu and Mo grades and recoveries, respectively. The correlation coefficient (R) values for the testing sets for Cu and Mo grades were 0.93, 0.94 and for their recoveries were 0.93, 0.92, respectively. The results discussed in this paper indicate that the proposed model can be used to predict the Cu and Mo grades and recoveries with a reasonable error. 展开更多
关键词 Artificial neural network Genetic algorithm Flotation column Grade Recovery Prediction
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建筑与建材
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《中国.城乡桥》 2000年第10期27-28,共2页
【正】 离子镀彩色镜面不锈钢生产技术 随着我国城市建设的日新月异和社会消费水平的日益提高,作为新一代建筑装潢材料——彩色镜面不锈钢正逐渐受到社会的广泛青睐。由于它具有绚丽多彩的色泽,易于营造豪华高雅的气氛。
关键词 色镜 管材 管件 铝塑复合管 系单位 离子镀 等级公路软 PEX管 镜面不锈钢 热熔连接
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