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Preliminary Studies on the Zoogeographic Divisions of Chinese Ground Spiders(Araneae:Gnaphosidae) 被引量:1
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作者 张超 《Agricultural Science & Technology》 CAS 2010年第6期7-10,共4页
This paper aims to carry out the preliminary study on the zoogeographic distributions of 166 species within Gnaphosidae by clustering method,and analyze and compare the similarities of 15 subregions in seven zoogeogra... This paper aims to carry out the preliminary study on the zoogeographic distributions of 166 species within Gnaphosidae by clustering method,and analyze and compare the similarities of 15 subregions in seven zoogeographic regions in China.The results suggested that the division of Northern China was coincident with the distribution pattern of Chinese ground spiders,but there was subregion recombination between the other regions.There was aggregation between Da Hinggan Mountains subregion in the Northeast,east plain subregion in Mengxin area and west hungriness subregion,between Tianshan mountainous subregion in Mengxin area,Qiangtang altiplano subregion and the southwest mountainous region subregion in Southwest,and between east hill plain subregion in central China,west mountainous region altiplano subregion,Min and Guang coastal subregion in south of China and south Dian mountainous region subregion.The other two subregions in the Northeast formed a region.Qinghai and south Xizang subregion in Qinghai-Xizang Region formed a branch independently. 展开更多
关键词 Gnaphosidae SPIDER Zoogeographic distributions Cluster analysis
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Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers(Ostrinia furnaealis) and Spiders(Xysticus ephippiatus) 被引量:7
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作者 YANG Dai-bin ZHANG Lin-na +2 位作者 YAN Xiao-jing WANG Zhen-ying YUAN Hui-zhu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期124-133,共10页
Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the secon... Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer (ACB) larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore, randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin's efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application. 展开更多
关键词 droplet distribution insecticide toxicity Asian corn borer SPIDER
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A Mechanical Model for the Adhesion of Spiders to Nominally Flat Surfaces 被引量:5
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作者 Alessandro Gasparetto Tobias Seidl Renato Vidoni 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第2期135-142,共8页
In dry attachment systems of spiders and geckos, van der Waals forces mediate attraction between substrate and animal tarsus. In particular, the scopula of Evarcha arcuata spiders allows for reversible attachment and ... In dry attachment systems of spiders and geckos, van der Waals forces mediate attraction between substrate and animal tarsus. In particular, the scopula of Evarcha arcuata spiders allows for reversible attachment and easy detachment to a broad range of surfaces. Hence, reproducing the scopula's roughness compatibility while maintaining anti-bunching features and dirt particle repellence behavior is a central task for a biomimetic transfer to an engineered model. In the present work we model the scopula of E. arcuata from a mechano-elastic point of view analyzing the influence of its hierarchical structure on the attachment behavior. By considering biological data of the gecko and spider, and the simulation results, the adhesive capabilities of the two animals are compared and important confirmations and new directives in order to reproduce the overall structure are found. Moreover, a possible suggestion of how the spider detaches in an easy and fast manner is proposed and supported by the results. 展开更多
关键词 BIONICS SPIDER dry adhesion mechano-elastic model hierarchical structure
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Predator perception of detritus and eggsac decorations spun by orb-web spiders Cyclosa octotuberculata:Do they function to camouflage the spiders? 被引量:2
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作者 Wenjin GAN Fengxiang LIU +1 位作者 Zengtao ZHANG Daiqin LI 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期379-387,共9页
Camouflage is one of the most widespread and powerful strategies that animals use to make detection/recognition more difficult. Many orb-web spiders of the genus Cyclosa add prey remains, plant debris, moults, and/or ... Camouflage is one of the most widespread and powerful strategies that animals use to make detection/recognition more difficult. Many orb-web spiders of the genus Cyclosa add prey remains, plant debris, moults, and/or eggsacs to their webs called web decorations. Web decorations resembling spider body colour pattern have been considered to camouflage the spider from predators. While this camouflage is obvious from a human's perspective, it has rarely been investigated from a predator's perspective. In this study, we tested the visibility of web decorations by calculating chromatic and achromatic contrasts of detritus and eggsae decorations built by Cyclosa octotubereulata, against four different backgrounds viewed by both bird (e.g., blue tits) and hymenopteran (e.g. wasps) predators. We showed that both juvenile and adult spiders on webs with detritus or egg-sac deco- rations were undetectable by both hymenopteran and bird predators over short and long distances. Our results thus suggest that decorating webs with detritus or eggsacs by C octotuberculata may camouflage the spiders from both hymenopteran and bird predators in their common habitats [Current Zoology 56 (3): 379-387, 2010]. 展开更多
关键词 SPIDER Web decorations Cyclosa octotuberculata CAMOUFLAGE Chromatic contrast Achromatic contrast
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Comparative transcriptomics highlights convergent evolution of energy metabolic pathways in group-living spiders 被引量:1
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作者 Han Yang Bin Lyu +1 位作者 Hai-Qiang Yin Shu-Qiang Li 《Zoological Research》 SCIE CAS CSCD 2021年第2期195-206,共12页
Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolutio... Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolution. Here, we conducted a comparative transcriptomic study and examined patterns of molecular evolution in two independently evolved group-living spiders and twelve solitary species. We report that positively selected genes among groupliving spider lineages are significantly enriched in nutrient metabolism and autophagy pathways. We also show that nutrient-related genes of group-living spiders convergently experience amino acid substitutions and accelerated relative evolutionary rates. These results indicate adaptive convergence of nutrient metabolism that may ensure energy supply in group-living spiders. The decelerated evolutionary rate of autophagy-related genes in group-living lineages is consistent with an increased constraint on energy homeostasis as would be required in a group-living environment. Together, the results show that energy metabolic pathways play an important role in the transition to group-living in spiders. 展开更多
关键词 AUTOPHAGY CANNIBALISM CONVERGENT Group-living NUTRIENT SPIDER
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Predatory Efficacy of Cotton Inhabiting Spiders on Bemisiatabaci, Amrascadevastans Thripstabaci and Helicoverpa armigera in Laboratory Conditions 被引量:1
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作者 Mohsin S B Li Yi-jing +7 位作者 Tang Li-jie Maqsood I Ting Ma-sun Han Le-meng Khalil U R Andleeb S Muhammad S K Saleem M A 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期48-53,共6页
Distinction of predator's diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems... Distinction of predator's diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems. In the current study, predatory efficacy of five spiders (Pardosa birmanica, Cyclosa insulana, Thomisus projectus, Plexippus paykulli and Lycosa terrestris) inhabiting the cotton fieldevaluated in the laboratory conditions maintained at (27+2)℃ temperature, 65%-5% relative humidity and 12 : 12 h of light and dark photoperiod. Four key cotton pests' viz. Bemisiatabaci, Amrascaderastans Thripstabaci and Helicoverpa armigera were utilized in the choice and no-choice predatory studies. The findings of current investigation revealed that each predatory spider utilized at least one pest species. Predation rate was found higher in the no-choice predation because of unavailability of substitutes feeding source. The investigation also indicated each predatory spider killed more pests than consumed. The findings of this study support the predatory role of spiders in controlling the cotton major pests. 展开更多
关键词 PREDATORY SPIDER EFFICACY cotton pest LABORATORY CONDITION
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Mitochondrial phylogenomics provides insights into the phylogeny and evolution of spiders(Arthropoda:Araneae)
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作者 Min Li Wen-Ting Chen +5 位作者 Qi-Lin Zhang Min Liu Cheng-Wei Xing Ya Cao Fang-Zhen Luo Ming-Long Yuan 《Zoological Research》 SCIE CAS CSCD 2022年第4期566-584,共19页
Spiders are among the most varied terrestrial predators,with highly diverse morphology,ecology,and behavior.Morphological and molecular data have greatly contributed to advances in the phylogeny and evolutionary dynam... Spiders are among the most varied terrestrial predators,with highly diverse morphology,ecology,and behavior.Morphological and molecular data have greatly contributed to advances in the phylogeny and evolutionary dynamics of spiders.Here,we performed comprehensive mitochondrial phylogenomics analysis on 78 mitochondrial genomes(mitogenomes)representing 29 families;of these,23 species from eight families were newly generated.Mesothelae retained the same gene arrangement as the arthropod ancestor(Limulus polyphemus),while Opisthothelae showed extensive rearrangement,with 12 rearrangement types in transfer RNAs(tRNAs)and control region.Most spider tRNAs were extremely truncated and lacked typical dihydrouridine or TΨC arms,showing high tRNA structural diversity;in particular,trnS1 exhibited anticodon diversity across the phylogeny.The evolutionary rates of mitochondrial genes were potentially associated with gene rearrangement or truncated tRNAs.Both mitogenomic sequences and rearrangements possessed phylogenetic characteristics,providing a robust backbone for spider phylogeny,as previously reported.The monophyly of suborder,infraorder,retrolateral tibial apophysis clade,and families(except for Pisauridae)was separately supported,and high-level relationships were resolved as(Mesothelae,(Mygalomorphae,(Entelegynae,(Synspermiata,Hypochilidae)))).The phylogenetic positions of several families were also resolved(e.g.,Eresidae,Oecobiidae and Titanoecidae).Two reconstructions of ancestral web type obtained almost identical results,indicating that the common ancestor of spiders likely foraged using a silk-lined burrow.This study,the largest mitochondrial phylogenomics analysis of spiders to date,highlights the usefulness of mitogenomic data not only for providing efficient phylogenetic signals for spider phylogeny,but also for characterizing trait diversification in spider evolution. 展开更多
关键词 spiders Mitochondrial genome Gene rearrangement Truncated tRNAs Trait evolution PHYLOGENOMICS
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The Predatory Function of Three Spiders to Two Insect Pests in Rice Within a Multi-species Co-existence System
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作者 LI Jian-quan, SHEN Zuo-rui and ZHAO Zhi-mo( College of Plant Protection , China Agricultural University, Beijing 100094 , P.R. China Department of Plant Protection , South-west Agricultural University, Chongqing 400716 , P.R. China) 《Agricultural Sciences in China》 CAS CSCD 2002年第4期391-396,共6页
The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) ... The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) was investigated, as well as how interference between and within species occurred, by using a quadratic regression rotational composite design. Six predation models derived from the analysis of interactions among and within predators and preys were developed. The total predatory capacity of spiders on rice insect pests after coexistence for one day can be expressed as follows: Y3 = 32.795 + 2.25X1 + 1.083X2 + 0.5X3 + 10.167X4 + 3.167X5 - 1.67X12 - 2.42X22 - 3.295X32 - 0.045X42 + 0.455X52 - 3.125X1X2 + 0.375X1X3 -0.625X1X4 - 0.375X1X5 + 0.375X2X3 - 0.875X2X4 + 0.125X2X5 + 0.375X3X4 - 0.375X3X5 + 0.125X4X5. The principal efficiency analysis using this model indicated that increases in insect pest density significantly increased predation by predators; this was much greater than the effect of any single predator. X4 had a greater effect than X5; however, X4 and X5 demonstrated little interspecific interference and even promoted each other and increased predation rates as the densities of the two pests increased. Among the three predators, an increase in the density of X, had the greatest effect on the increase in predation, X3 had the second, X2 the third greatest effect. As predator density increased inter- and intra-species interference occurred, which were largely related to the size, activity, niche breadth, niche overlap and searching efficiency of the predators. X2 produced the greatest interference between different individuals and between any other predator species. X3 had the second greatest, which reduced predation levels at high predator densities. Because of these factors, the highest predation rate was obtained at a prey density of 120 per 4 rice-hills. The optimal proportion of the three predators in the multi-predator prey system was X1: X2: X3 = 5.6:1.3:4.1. 展开更多
关键词 spiders Predation BIO-CONTROL Intra-species relationships Co-existence system Interaction Intraspecific competition Interspecific competition Animal behavior Natural enemies Rice insect pest
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Investigation on Species of Spiders in Tea Plantations in Enshi Region of China
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作者 Cui Qingmei Zhang Qiang +3 位作者 Hou Weihua Li Weidong Dai Juhui Yuan Chengxiao 《Plant Diseases and Pests》 CAS 2013年第1期15-17,共3页
The spider resources in tea plantations in Enshi region have been investigated and 51 species of spiders belonging to 22 families have been identified in the paper. The dominant species are clarified and their directo... The spider resources in tea plantations in Enshi region have been investigated and 51 species of spiders belonging to 22 families have been identified in the paper. The dominant species are clarified and their directory and distribution status are also listed in the paper. 展开更多
关键词 Enshi Tea plantation SPIDER INVESTIGATION
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Species Investigation and Population Dynamic of Spiders in Tea Gardens in Northern Guangxi
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作者 Zhao Yingjie Wen Zhaoming +1 位作者 Bai Xianli Liu Shishi 《Plant Diseases and Pests》 CAS 2015年第6期38-40,共3页
A systematic investigation on spiders in a tea garden of Guilin Institute of Tea Sciences was conducted. The results showed that totally 687 specimens were collected, belonging to 34 species, 27genera, 14 families, 2 ... A systematic investigation on spiders in a tea garden of Guilin Institute of Tea Sciences was conducted. The results showed that totally 687 specimens were collected, belonging to 34 species, 27genera, 14 families, 2 suborders, and a new record species Trochosa suiningensis in Guangxi was found. Spider is a ma- jor developing natural enemy group of insect pests in tea garden, with features of wide distribution, large quantity, long duration, strong predatory and stress resist- ance, which has strong predation on adults and nymphs of Empoasca vitis and young larvae of Ectropis oblique. The population of spiders in tea garden significantly increases after middle June, and reaches the peak in July and August every year. 展开更多
关键词 spiders in tea garden Field investigation Population dynamics
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Diversity and Distribution of Spiders in Southwestern Nigeria
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作者 Oyeniyi Abiola Oyewole Oyeseyi Joshua Oyelade 《Natural Resources》 2014年第15期926-935,共10页
The study of diversity and distribution of spiders was carried out at Obafemi Awolowo University, Southwestern Nigeria, in wet and dry seasons between October 2012 and April 2014. Spiders were collected from five diff... The study of diversity and distribution of spiders was carried out at Obafemi Awolowo University, Southwestern Nigeria, in wet and dry seasons between October 2012 and April 2014. Spiders were collected from five different sampling sites in the study area: cultivated land, open field, hill area, house dwelling and aquatic habitat. We found 1824 individuals belonging to 19 different spider families in the study area. 9 families of spiders were present in the hill habitat;12 families of spiders were present in the open field habitat;6 families of spiders were present in house habitat;9 families of spider were present in aquatic habitat. All the 19 families of spiders were present in cultivated habitat. Therefore, cultivated habitat hosted the largest number of spider families in the area of study while house dwellers hosted the least number of spider families. Spiders are evenly distributed among the five habitats in this study and the fifth habitat, teaching and research farm representing cultivated area has the highest distribution of spider species. All the species recorded in Southwestern Nigeria were found in this habitat. In conclusion, 19 different spider families are recorded in Obafemi Awolowo University, Nigeria, during this study. These have enriched the collection of spider in Natural History Museum, Obafemi Awolowo University, Southwestern Nigeria. 展开更多
关键词 SPIDER Families HABITATS SOUTHWESTERN NIGERIA
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Structural analysis of silk using solid-state NMR
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作者 Tetsuo Asakura 《Magnetic Resonance Letters》 2024年第3期19-34,共16页
Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric press... Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric pressure.The dragline silk fiber,which is essentially a spider's lifeline,surpasses the strength of a steel wire of equivalent thickness.Regrettably,humans have yet to replicate this process to produce fibers with similar high strength and elasticity in an eco-friendly manner.Therefore,it is of utmost importance to thoroughly comprehend the extraordinary structure and fibrillation mechanism of silk,and leverage this understanding in the manufacturing of high-strength,high-elasticity fibers.This review will delve into the recent progress in comprehending the structure of silks derived from silkworms and spiders,emphasizing the distinctive attributes of solidstate NMR. 展开更多
关键词 SILK Bombyx mori SPIDER Solid-state NMR STRUCTURE
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完美音浪——法拉利12CILINDRI SPIDER
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作者 王迪 《世界汽车》 2024年第7期16-23,共8页
近日,法拉利12Cilindri Spider在迈阿密海滩上的一场独家活动上亮相。作为一款设计理念承袭自20世纪50与60年代法拉利Gran Turismo敞篷车的新款车型,该车将公路赛车无与伦比的性能、12缸发动机声浪以及长途驾驶舒适性结合在一起,并在设... 近日,法拉利12Cilindri Spider在迈阿密海滩上的一场独家活动上亮相。作为一款设计理念承袭自20世纪50与60年代法拉利Gran Turismo敞篷车的新款车型,该车将公路赛车无与伦比的性能、12缸发动机声浪以及长途驾驶舒适性结合在一起,并在设计上打破了法拉利双座berlinetta Spider跑车一贯的肌肉感,采用了一种更加未来主义、建立在纯粹形式基础上的设计语言。 展开更多
关键词 法拉利 驾驶舒适性 公路赛车 新款车型 纯粹形式 SPIDER 敞篷车 未来主义
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浙江省蜘蛛名录(续) 被引量:1
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作者 陈樟福 张贞华 《杭州师范学院学报》 1991年第3期74-81,共8页
狼蛛科 Lycosidae Sundevall, 1833 豹蛛属 Pardosa Latreilles, 1804 拟环纹豹蛛 Pardosa pseudoannulata (Bosenberg et Strand, 1906 Tarentula pseudoanulata Bosenberg et Strand,1906:319-320, figs. 323, 326, 334, 338. Lycosa ... 狼蛛科 Lycosidae Sundevall, 1833 豹蛛属 Pardosa Latreilles, 1804 拟环纹豹蛛 Pardosa pseudoannulata (Bosenberg et Strand, 1906 Tarentula pseudoanulata Bosenberg et Strand,1906:319-320, figs. 323, 326, 334, 338. Lycosa pseudoterricola Schenkel, 1938:199-201 fig, 66a. Lycosa pseudoannulata 宋大祥, 1978:1-2, fig 2. Lycosa cinnameovittata Schenkel, 1963 全省。安徽、台湾。K.J 星豹蛛 Pardosa astrigera Koch, 1878 Pardosa T-insignita Bosenberg et Strand, 1906: 324-325, figs.109, 334, 337 Pardosa astrigera Koch, 1878 全省。安徽、台湾。 展开更多
关键词 ZHEJIANG spiders.
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抢先式多线程Spider在智能搜索引擎中的实现 被引量:3
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作者 董瑞洪 张秋余 +1 位作者 唐静兵 张涛 《计算机工程》 EI CAS CSCD 北大核心 2005年第18期90-92,共3页
互联网的迅速发展,导致了网上信息的爆炸性增长。智能搜索引擎技术已经成为计算机工业界和学术界争相研究、开发的对象。文章在分析网络蜘蛛的工作原理的基础上,结合多线程、类的设计等技术,设计了一种抢先式多线程的Spider程序,并给出... 互联网的迅速发展,导致了网上信息的爆炸性增长。智能搜索引擎技术已经成为计算机工业界和学术界争相研究、开发的对象。文章在分析网络蜘蛛的工作原理的基础上,结合多线程、类的设计等技术,设计了一种抢先式多线程的Spider程序,并给出了该系统运行的结果。 展开更多
关键词 搜索引擎 抢先式 SPIDER 多线程 类的设计
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实时嵌入式系统总线的容错技术 被引量:6
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作者 任秀丽 张翠华 《仪器仪表学报》 EI CAS CSCD 北大核心 2005年第z2期578-581,共4页
飞机或汽车上使用的电子设备和控制系统都是分布式的、容错的计算机系统,它们是由各种功能模块组合构成的。模块化结构提供的基本服务就是在不同的组件之间进行信息通信,相对于安全至上的应用来说,把这种结构统称为总线或数据总线。针... 飞机或汽车上使用的电子设备和控制系统都是分布式的、容错的计算机系统,它们是由各种功能模块组合构成的。模块化结构提供的基本服务就是在不同的组件之间进行信息通信,相对于安全至上的应用来说,把这种结构统称为总线或数据总线。针对实时嵌入式系统的4种总线SAFEbus、TTA、SPIDER和FlexRay的拓扑结构、性能和实现技术进行了详细地介绍。 展开更多
关键词 总线 SAFEbus TTA SPIDER FLEXRAY
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基于Rabin指纹方法的URL去重算法 被引量:8
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作者 梁正友 张林才 《计算机应用》 CSCD 北大核心 2008年第S2期185-186,203,共3页
针对现有URL检索算法占用存储空间较大,对重复率高的URL集合检索速度较慢,使Web Spider的效率降低的问题,提出了一种改进的URL去重算法。此算法基于Rabin指纹方法,以URL的指纹为地址,仅用一位数据标识一条URL,每次检索仅需对相应的一位... 针对现有URL检索算法占用存储空间较大,对重复率高的URL集合检索速度较慢,使Web Spider的效率降低的问题,提出了一种改进的URL去重算法。此算法基于Rabin指纹方法,以URL的指纹为地址,仅用一位数据标识一条URL,每次检索仅需对相应的一位数据的值做一次判断。实验表明,该算法能有效去除URL集合中重复的URL,提高检索速度。 展开更多
关键词 URL去重 Rabin指纹方法 WEB SPIDER
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关于搜索引擎的研究综述 被引量:17
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作者 沈贺丹 潘亚楠 邵良杉 《计算机技术与发展》 2006年第4期147-149,152,共4页
由于目前搜索服务被越来越多的用户所认识和青睐,各样的搜索引擎也应运而生。文中阐述了搜索引擎的工作原理,并对搜索引擎按照不同的依据对其进行分类。介绍并比较目前较为有名气同时其发展历史也推进了搜索引擎的发展的几个搜索引擎,... 由于目前搜索服务被越来越多的用户所认识和青睐,各样的搜索引擎也应运而生。文中阐述了搜索引擎的工作原理,并对搜索引擎按照不同的依据对其进行分类。介绍并比较目前较为有名气同时其发展历史也推进了搜索引擎的发展的几个搜索引擎,最后提出目前搜索引擎所存在的问题。 展开更多
关键词 SPIDER 超链分析 元搜索引擎
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DNA条形码专用R包及其主要功能简介 被引量:2
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作者 金倩 阮倩倩 +2 位作者 陈芬 罗桂杰 张爱兵 《环境昆虫学报》 CSCD 北大核心 2017年第3期485-492,共8页
S_(PIDER)和BarcodingR软件包作为DNA条形码研究的专用R软件包,整合了基于DNA条形码的物种识别算法和数据分析策略,避免了各种非商业用途软件的局限性,为DNA条形码的研究提供了便捷性和可操作性。本文对SPIDER和BarcodingR软件包的主要... S_(PIDER)和BarcodingR软件包作为DNA条形码研究的专用R软件包,整合了基于DNA条形码的物种识别算法和数据分析策略,避免了各种非商业用途软件的局限性,为DNA条形码的研究提供了便捷性和可操作性。本文对SPIDER和BarcodingR软件包的主要功能进行整体介绍,并以西藏夜蛾科COI、松毛虫属ITS等数据为例,进行主要函数的演示分析,希望为昆虫DNA条码的应用分析提供帮助。 展开更多
关键词 DNA条形码 R语言 SPIDER BarcodingR
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通用互联网信息采集系统的设计与初步实现 被引量:9
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作者 杜义华 及俊川 《计算机应用研究》 CSCD 北大核心 2005年第1期187-189,210,共4页
通过建立网页资源库,结合Spider技术、内容分析技术、引入用户数据项和替换抽取指令编辑器等,提供和定制可视化通用性较强的互联网信息采集系统,能定期自动跟踪相关网站或网页,进行比较分析、抽取、规整入库、分类等,从互联网上获取所... 通过建立网页资源库,结合Spider技术、内容分析技术、引入用户数据项和替换抽取指令编辑器等,提供和定制可视化通用性较强的互联网信息采集系统,能定期自动跟踪相关网站或网页,进行比较分析、抽取、规整入库、分类等,从互联网上获取所需信息。 展开更多
关键词 互联网信息采集系统 网络信息挖掘 SPIDER
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