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基于matlab和小波分析“一体化”法在医学图像处理中应用 被引量:1
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作者 王永飞 《安徽广播电视大学学报》 2018年第2期125-128,共4页
在随机选用了互联网脑部CT图像和医学教育网基础医学理论部分的肝硬化CT图像的基础上,分析了图像数据信息,提出"一体化"法医学图像数据分析方法,对医学图像数据降噪、增强、融合和边缘检测进行了实验论证,与传统医学图像数据... 在随机选用了互联网脑部CT图像和医学教育网基础医学理论部分的肝硬化CT图像的基础上,分析了图像数据信息,提出"一体化"法医学图像数据分析方法,对医学图像数据降噪、增强、融合和边缘检测进行了实验论证,与传统医学图像数据分析方法进行降噪实验比较,论证了"一体化"法处理医学图像的有效性。 展开更多
关键词 医学图像处理 “一体化”法 降噪 边缘检测
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Multiple vehicle routing problem integrated reverse logistics with fuzzy reverse demands
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作者 李建 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期222-227,共6页
A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in t... A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in the demands of the clients. The deliveries of every client as uncertain parameters are expressed as triangular fuzzy numbers. In order to describe MVRPRL, a multi-objective fuzzy programming model with credibility measure theory is constructed. Then the simulationbased tabu search algorithm combining inter-route and intra-route neighborhoods and embedded restarts are designed to solve it. Computational results show that the tabu search algorithm developed is superior to sweep algorithms and that compared with handling each on separate routes, the transportation costs can be reduced by 43% through combining pickups with deliveries. 展开更多
关键词 reverse logistics pickup and delivery credibility measure theory tabu search algorithm fuzzy simulation
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One Step Preparation of Sulfonated Solid Catalyst and Its Effect in Esterification Reaction 被引量:2
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作者 康世民 常杰 范娟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期392-397,共6页
A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonate... A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g^-1, 0.78 mmol·g^-1, 2.18 mmol·g^-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong^-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively. 展开更多
关键词 red liquor solids sulfonated solid catalyst CARBONIZATION ESTERIFICATION
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Comprehensive assessment method for environmental impact of railway based on geographic information system 被引量:1
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作者 吴小萍 陈秀方 +3 位作者 马超群 杨晓宇 冉茂平 孟祥定 《Journal of Central South University of Technology》 2004年第3期340-342,共3页
By integrating the merits of the map overlay method and the geographic information system (GIS), a GIS based map overlay method was developed to analyze comprehensively the environmental vulnerability around railway a... By integrating the merits of the map overlay method and the geographic information system (GIS), a GIS based map overlay method was developed to analyze comprehensively the environmental vulnerability around railway and its impact on the environment, which is adapted for the comprehensive assessment of railway environmental impact and the optimization of railway alignments. The assessment process of the GIS based map overlay method was presented, which includes deciding the system structure and weights of assessment factors, making environmental vulnerability grade maps, and evaluating the alternative alignments comprehensively to obtain the best one. With the GIS functions of spatial analysis, such as overlay analysis and buffer analysis, and functions of handling attribute data, the GIS based map overlay method overcomes the shortcomings of the existing map overlay method and the conclusion is more reasonable. In the end, a detailed case study was illustrated to verify the efficiency of the method. 展开更多
关键词 railway planning environmental impact assessment geographic information system graph overlay method
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Feasibility study on the integration of urban and rural minimum living security system based on SWOT model 被引量:1
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作者 CHEN Likaag 《International English Education Research》 2017年第2期14-16,共3页
This paper uses SWOT analysis, feasibility analysis of integration of urban and rural residents in China, including the overall analysis of the urban and rural integration China internal conditions, mainly for its ove... This paper uses SWOT analysis, feasibility analysis of integration of urban and rural residents in China, including the overall analysis of the urban and rural integration China internal conditions, mainly for its overall advantages and disadvantages are analyzed; and the external environment, the system is mainly to raise the opportunities and threats were analyzed; in these. The external conditions are analyzed based on the construction of SWOT strategic matrix, found the advantages and disadvantages of the reform process of the integration of urban and rural subsistence allowances system in coexist, opportunities outweigh the challenges, so China's overall urban and rural integration construction is feasible. 展开更多
关键词 Minimum living security: SWOT analysis FEASIBILITY
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Synthesis of 2-Methyl-4-methoxyaniline from o-Nitrotoluene Using Pt/C and Acidic Ionic Liquid as Catalyst System
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作者 LIU Yingxin LI Xiying FANG Yanyan ZHANG Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期701-704,共4页
2-Methyl-4-methoxyaniline (MMA) was synthesized by one-pot method through the hydrogenation and Bamberger rearrangement of o-nitrotoluene in methanol using acidic ionic liquid and 3% Pt/C as catalyst system. The eff... 2-Methyl-4-methoxyaniline (MMA) was synthesized by one-pot method through the hydrogenation and Bamberger rearrangement of o-nitrotoluene in methanol using acidic ionic liquid and 3% Pt/C as catalyst system. The effects of ionic liquid type, dosage of ionic liquid and 3% Pt/C, reaction temperature and reaction pressure on o-nitrotoluene conversion and MMA selectivity were investigated. The results indicated that the imidazolium-based acidic ionic liquid which contains SO3H-functionalized cation showed higher selectivity to MMA than other acidic ionic liquids used in this work. Using 1-(propyl-3-sulfonate)-3-methylimidazolium hydrosulfate ([HSO3-pmim][HSO4]) as the acid catalyst, the selectivity to MMA was as high as 67.6% at 97.8% of o-nitrotoluene conversion. As 3% Pt/C increased from 0.01 g to 0.025 g, the selectivity to MMA decreased from 73.4% to 62.5%, because of the hydrogenation of intermediate o-methyl-phenylhydroxylamine to o-toluidine becoming more dominant. An increase in hydrogen pressure also had obviously dramatic effect in lowering the MMA selectivity. After easy separation from the products, the catalyst system could be reused at least 3 times. 展开更多
关键词 acidic ionic liquid Bamberger rearrangement 2-methyl-4-methoxyaniline O-NITROTOLUENE hydrogenation
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Experimental validation of an integrated optimization design of a radial turbine for micro gas turbines 被引量:1
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作者 Lei FU Zhen-ping FENG +3 位作者 Guo-jun LI Qing-hua DENG Yan SHI Tie-yu GAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2015年第3期241-249,共9页
The aerodynamic performance, structural strength, and wheel weight are three important factors in the design process of the radial turbine for micro gas turbines. This study presents the experimental validation proces... The aerodynamic performance, structural strength, and wheel weight are three important factors in the design process of the radial turbine for micro gas turbines. This study presents the experimental validation process of this integrated optimization design method by using the similarity theory. Cold modeling tests and investigations into the aerodynamic characteristics were performed. Experimental results showed that the aerodynamic efficiency of the micro radial turbine is 84.3% at the design point while also satisfying the aerodynamic and strength requirements. Meanwhile, the total weight of the turbine wheel is 3.8 kg which has only a 52.8% mass of the original design. This indicates that the radial turbine designed through this technique has a high aerodynamic performance, and thus can be applied to micro gas turbines. The results validated that this integrated optimization design method is reliable. 展开更多
关键词 Micro radial turbine Integrated optimization design Bearing and shafting Performance test
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Ultrathin ZnO membranes a few atomic layers in thickness
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作者 YIN JianBo XIA HuaRong +1 位作者 LIANG Jia ZHANG GengMin 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第2期315-321,共7页
For the first time we fabricated ZnO membranes with thicknesses of 2.4 nm by a facile one-pot synthesis in aqueous solution.The crystal analysis revealed that the hexagonal ZnO membranes were about 10 atomic layers in... For the first time we fabricated ZnO membranes with thicknesses of 2.4 nm by a facile one-pot synthesis in aqueous solution.The crystal analysis revealed that the hexagonal ZnO membranes were about 10 atomic layers in thickness.The ZnO membranes bent,scrolled,intersected with each other,and self-assembled to particles in micrometre size.The hierarchical assemblies showed sponge-like structures with room inside.In the growth process,a cationic polyelectrolyte was utilized to modulate growth behavior of the ZnO crystals.As a result,the preferred growth direction of ZnO membranes is along 0110,which was perpendicular to[0001]growth direction in a typical hydrothermal synthesis.The growth mechanism of the membranes was also discussed. 展开更多
关键词 ZNO 2D materials NANOSHEETS hierarchical structures
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Multi-band design for one-dimensional phononic crystals
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作者 ZHANG Pei WANG ZhenYu +1 位作者 ZHANG YongQiang LIANG Xu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第7期1253-1262,共10页
Periodic composites with band gaps that prevent the propagation of elastic waves in certain frequency ranges can be used to control waves for a variety of engineering applications. Although studies on the characterist... Periodic composites with band gaps that prevent the propagation of elastic waves in certain frequency ranges can be used to control waves for a variety of engineering applications. Although studies on the characteristics of these materials, which are called phononic crystals (PCs), have yielded a large number of positive results in recent years, there is still a lack of effective design methods. In this work, a multi-objective optimization approach based on the band gap mechanism and an intelligent algorithm is used to design a one-dimensional (1D) slab construction of PCs. The design aims to fit pre-determined bands by arranging the available materials properly. Obtained by analyzing the wave transmission in periodic layers, the objective functions are linked to the optimization program to obtain a proper solution set. The results of the numerical simulations demonstrate that without constructing complicated structures, the design method is able to produce PCs that overcome the limitations of two-component PCs and hence can feasibly and effectively achieve the design targets. The design approach presented in this paper can be extended to two-or three-dimensional systems and has great potential for the development of sound/ultrasound isolation structures, multiple band frequency filters, and other applications. 展开更多
关键词 phononic crystals multi-band design multi-objective optimization
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