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极小化总完工时间批调度问题的两种蚁群算法  [PDF]
许瑞,陈华平,邵浩,王栓狮
计算机集成制造系统 , 2010,
Abstract: 针对考虑工件尺寸不同,求解目标为极小化总完工时间的批调度问题,考虑不同的编码方式,提出了基于工件序列的蚁群算法和基于批序列的蚁群算法。基于工件序列的蚁群算法算法采用传统的工件序列编码,需要启发式规则进行分批;基于批序列的蚁群算法算法利用蚁群算法构建性编码的特点,不需要启发式规则,而采取直接分批的方式编码,充分发挥蚁群算法自身的搜索能力。针对总完工时间的优化目标,基于批序列的蚁群算法算法引入批权重构建启发式信息;针对批调度特有性质,基于批序列的蚁群算法算法加入新的信息素更新变量,设置不同的信息素初始值,并采用局部优化技术等改进措施,以克服传统蚁群算法收敛速度慢,易陷入局部最优的缺点。通过对比实验验证了所提算法的有效性。
穴蚁蛉幼虫全长均一化cDNA文库的构建  [PDF]
杨展,李广宏,邱壮伟,王欢歌,苏志坚,黄亚东
生物技术通报 , 2011,
Abstract: 通过构建穴蚁蛉幼虫(俗称蚁狮)全长均一化cDNA文库,以期了解蚁狮的抗菌肽、毒素蛋白以及其它药用蛋白种类,为日后筛选、克隆表达和分离纯化这些药用蛋白奠定基础。用针刺诱导蚁狮产生抗菌物质后,分离纯化总RNA,结合SMART全长文库与DSN(duplex-specificnuclease)均一化技术,构建全长均一化cDNA文库,并通过平板计数和菌落PCR方法鉴定文库。随机挑选192个单克隆进行5′端测序,并与NCBI数据库进行比对分析。结果显示,构建出的文库平均插入片段长度为1200bp,原始文库的滴度达到7.5×105CFU/mL,而扩增文库则为1.95×1011CFU/mL。在所挑选的单克隆中,共获得190条有效序列,平均读长1340bp,文库重组率达到98.96%。与NCBI数据库比对后发现,这些序列可能是一些编码蚁狮免疫、消化及毒性蛋白的基因。
连续约束蚁群优化算法的构建及其在丁烯烷化过程中的应用  [PDF]
贺益君,陈德钊
化工学报 , 2005,
Abstract: 经典蚁群系统只适用于离散问题,缺少处理约束的专门机制.基于蚁群觅食的生物学行为,以搜索最优食物源为目标,将约束纳入食物源优劣评价的启发式规则,采用成群募集和海量募集两种方式,并辅以局部搜索,以此引导蚁群寻找可行域中的最优解,构建为适用于连续约束优化问题的蚁群系统(constrainedantcolonysystem,CACS).测试实例表明,CACS具有良好的适用性及全局优化性能,将它应用于丁烯烷化过程的约束优化,取得了令人满意的结果.
Greenbelt Systems Play an Important Role in the Prevention of Landscape Degradation Due to Urbanization  [cached]
Yong-Chan Cho,Hyun-Je Cho,Chang-Seok Lee
Journal of Ecology and Field Biology , 2009,
Abstract: Greenbelts were designated by the Korean government in 1971 in 14 large cities to preventuncontrolled urban expansion. Recently, deregulation of the greenbelt system has resulted in further development,but the ecological role of greenbelts has not been fully considered when decisions about urban managementare being made. We examined the ecological roles of the greenbelt system in the Seoul metropolitan areaand prepared sustainable management and improvement plans based on our analysis of landscape characteristicsusing satellite images covering a ~30-year period. The loss of forest cover during this period in thegreenbelt areas was lower than that in the areas outside and inside of the greenbelt. Fragmentation of forestcover was correlated with the pattern of loss of forest cover. The NDVI of the greenbelt remained steady at 90%of that in outside of the GB for three decades. This suggests that the greenbelt system has performed its primaryroles well. However, the remaining green space was not adequate to provide a sink for air pollutants even whenthe greenbelt area was included. We discuss how the negative effects of urbanization can be reduced throughsustainable management and restoration to promote ecological functioning in greenbelts and urban landscapes.
Urban Containment Policies and the Protection of Natural Areas: The Case of Seoul's Greenbelt
David N. Bengston,Yeo-Chang Youn
Ecology and Society , 2006,
Abstract: Countries around the world have responded to the problems associated with rapid urban growth and increasingly land-consumptive development patterns by creating a wide range of policy instruments designed to manage urban growth. Of the array of growth management techniques, urban containment policies are considered by some to be a promising approach. This paper focuses on greenbelts, the most restrictive form of urban containment policy. The long-standing greenbelt of Seoul, Republic of Korea is examined as a case study. Seoul's greenbelt has generated both significant social costs and benefits. Costs include higher land and housing prices in the urban area surrounded by the greenbelt, additional costs incurred by commuters who live beyond the greenbelt and work in Seoul, and increased congestion and related quality of life impacts. Benefits include the amenity value of living near the greenbelt, recreational resources, bequest and heritage values, fiscal savings due to increased efficiency in the provision of public services and infrastructure, and a wide range of life-supporting ecosystem services. After standing virtually unchanged for almost three decades, Korea's greenbelt policy is currently being revised and weakened, largely due to pressure from greenbelt landowners and developers. Although there is no definitive answer to the question of whether Seoul would be a more or less "sustainable city" today without the greenbelt, it is certain that in the absence of the greenbelt, Seoul would have lost much of its rich natural heritage and essential ecosystem services.
Ecological planning on greenbelt surrounding mega city, Beijing
北京市环城绿化隔离带生态规划

OUYANG Zhi-Yun,
欧阳志云

生态学报 , 2005,
Abstract: Regarding the importance of greenbelt functions for urban development, this article analyzes the necessity for developing greenbelt surrounding the mega city, Beijing. Due to more serious urban problems caused by fast urbanization, the major services or functions that can be fulfilled through greenbelt implementation are analyzed. They are: (1) to control urban unlimited sprawl and reactivate the Separate Centralized-Functional Group developing pattern. (2) to optimize urban landscape pattern and set up the...
Spatiotemporal characteristics of fluoride accumulation in several greenbelt plants in Foshan City of Guangdong Province
佛山市几种绿地植物氟化物时空累积特征

LI Han-e,WANG Zhi-yun,HU Xian-cong,TAN Jia-de,LU Yao-dong,ZHAO quan,HE Li-li,
李寒娥
,王志云,胡羡聪,谭家得,陆耀东,赵权,何莉莉

生态学杂志 , 2007,
Abstract: The fluoride concentration in the leaves of Ficus virens var. sublanceolata, Ficus microcarpa, Ficus benjamina, Mangifera indica, Michelia alba and Elaeocarpus apiculatus grown in the Fushan urban greenbelt systems and that in the air above the greenbelt systems were measured, with their correlations analyzed. The results showed that the fluoride concentration in the air above test greenbelt systems ranked in the order of industrial greenbelt> traffic greenbelt>attached greenbelt in college campus>production greenbelt>park greenbelt. The air fluoride concentration above industrial greenbelt was 3.4 times as high as that above park greenbelt, and in all test greenbelt systems, the leaves of or two-year-old plants had an increasing fluoride concentration with time. There was a high correlation between the fluoride concentrations in air and plant leaves, which reflected the spatial characteristics of fluoride accumulation in greenbelt plants. The fluoride concentrations in the leaves of one- and two-year-old F. microcarpa and F. benjamina, one-year-old M. indica, and two-year-old M. alba could better indicate the air fluoride concentration in the urban greenbelt systems of Fushan City.
中国小首螨属一新种记述──(蚂螨亚纲:小首螨科)  [PDF]
昆虫分类学报 , 1994,
Abstract: 中国小首螨属一新种记述(蚂螨亚纲:小首螨科)高建荣,邹萍上海农学院园林环境科学系,上海市201101上海市农业科学院食用菌研究所,上海市201106关键词蝉螨亚纲,小首螨科,小首螨属,新种小首螨属(A。rOPhenaxNewst。dandDuvall...
基于MapReduce的蚁群算法  [PDF]
吴昊,倪志伟,王会颖,+
计算机集成制造系统 , 2012,
Abstract: 云计算环境下应用蚁群算法分布式并行对问题进行求解的研究较少,且蚁群算法存在搜索时间长和易收敛于非最优解的缺陷,当问题的规模较大时求解困难。为此应用云计算技术将蚁群算法并行化,提出基于MapReduce的蚁群算法。该算法将分治思想和模拟退火算法融入蚁群算法,改进其缺陷,并应用于求解较大规模的旅行商问题。仿真实验取得了较好的效果,且获得了测试实例gr666的新解。
GIS-based study on spatial structure of urban greenbelt landscapes: Taking Ningbo City as an example
基于GIS的城市绿地景观空间结构研究——以宁波市为例

ZHOU Ting-Gang,
周廷刚

生态学报 , 2003,
Abstract: Urban greenbelt landscapes, including park, street, road, and courtyard greenbelts, are an important component of urban ecosystems. The study of urban greenbelt landscapes is essential for quantifying and improving the quality a city's environment. In this paper, based on the spatial characteristics of urban greenbelt landscape, an index system and content were put forward for urban greenbelt landscape evaluation. The classification and distribution of urban greenbelt landscape patches, and their spatial ch...
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