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Framework to Model User Request Access Patterns in the World Wide Web

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Journal of Software Engineering and Applications 2024年第2期17卷 69-88页

作者： richard Hurley Robert Sturgeon Department of Computer Science Trent University Peterborough ON Canada

In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pages. Our framework model consists of three sub-models: one for user file access, one for web pages, and one for storage servers. Web pages are assumed to consist of different types and sizes of objects, which are characterized using several categories: articles, media, and mosaics. The model is implemented with a discrete event simulation and then used to investigate the performance of our system over a variety of parameters in our model. Our performance measure of choice is mean response time and by varying the composition of web pages through our categories, we find that our framework model is able to capture a wide range of conditions that serve as a basis for generating a variety of user request patterns. In addition, we are able to establish a set of parameters that can be used as base cases. One of the goals of this research is for the framework model to be general enough that the parameters can be varied such that it can serve as input for investigating other distributed applications that require the generation of user request access patterns.

关键词： Performance Modelling World Wide Web Simulation User Request Access Patterns Framework

Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains

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Plant Diversity 2024年第3期46卷 321-332页

作者： Jieshi Tang Xiaoyan Fan richard I.Milne Heng Yang Wenjing Tao Xinran Zhang Mengyun Guo Jialiang Li Kangshan Mao Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610065PR China Institute of Molecular Plant Sciences University of EdinburghEdinburgh EH93JHUK School of Ecology and Environment Tibet UniversityLhasa 850000PR China

Biogeographical barriers to gene flow are central to plant *** East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across *** we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern *** and migration hypotheses were tested using coalescent-based *** historical gene flow was observed between the western and eastern groups of ***,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central ***-borne pollen and seeds may have facilitated the dispersal of *** following prevalent northwest winds in the *** also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of *** niche modeling suggested that *** has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 *** phylogeographic pattern of *** reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate *** study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

关键词： Chloroplast DNA Microsatellite Phylogeographic break Populus rotundifolia Quaternary history Wind direction

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雷达频率综合器综述

航空兵器 1992年第1期 43-52页

作者： Zvi Galani richard A.campbell 曹旭东 IEE IEE 高级会员高级会员

本文综述了适用于雷达系统的频率综合技术和雷达系统对频率综合器的要求——这对于选择频率综合方法和选用频综器器件有着直接的影响;讨论了直接频率综合方案和间接频率综合方案以及它们各自的优缺点,并提供了具有代表性的实例。本文还... 详细信息

本文综述了适用于雷达系统的频率综合技术和雷达系统对频率综合器的要求——这对于选择频率综合方法和选用频综器器件有着直接的影响;讨论了直接频率综合方案和间接频率综合方案以及它们各自的优缺点,并提供了具有代表性的实例。本文还对分析步骤进行了简要的讨论,并对频综器的关键器件及其发展趋势进行了评述。

关键词：雷达频率综合器

Superdirective Circular Arrays of Electric and Huygens Dipole Elements

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Electromagnetic Science 2024年第1期2卷 38-62页

作者： richard W.Ziokowski TheUniversityofArizona TucsonAZ85721USA

Uniform circular arrays(UCAs)provide both omnidirectional(360°)and directive(sector)coverage of the azimuthal *** versions with unidirectional,high front-to-back ratio(FTBR)properties could provide the radiated field char-acteristics being pursued for NextG wireless networks and their perceived *** UCA configurations–full,semi-circular,and sector–that radiate vertically-polarized(VP)fields and are composed of either omnidirectional electric dipole ele-ments or unidirectional Huygens dipole elements are analyzed first with conventional methods as reference *** omni-and uni-directional element configurations are then treated with several optimization techniques:the classic Rayleigh-quotient(RQ)method and its unidirectional-constrained version;the eigenbeam decomposition and synthesis(EBDS)technique used to design su-perdirective acoustic receiving arrays;and the Bessel-azimuthal multipole(BEAM)approach developed *** arrays are identified as being superdirective with extremely high FTBR *** performance characteristics of the arrays of unidirectional elements are demonstrated to be superior in ***,it is shown that larger radius arrays with RQ-specified excitation amplitudes are robust to changes in them whereas the outcomes of the corresponding small radius versions are *** the other hand,the BEAM-optimized densely-packed small-radius superdirective arrays are quite tolerant to those variations while generating unidirectional pseudo-needle beams.

关键词： Directivity Huygens dipole antennas Multipoles Needle radiation Optimization Superdirective arrays Uniform circular arrays.

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波普先生的企鹅（十二）

疯狂英语(初中天地) 2024年第1期 53-54页

作者： richard and Florence Atwater

最终的结果皆大欢喜，电影公司老板决定在企鹅们去北极之前拍一段短片，当然，波普先生也得到了一笔报酬。时间也来到了企鹅们离开的日子。But at last everything was ready, and the day came when the Poppers were to go down and s...

最终的结果皆大欢喜，电影公司老板决定在企鹅们去北极之前拍一段短片，当然，波普先生也得到了一笔报酬。时间也来到了企鹅们离开的日子。But at last everything was ready, and the day came when the Poppers were to go down and say good-by. Bill and Janie ran all over the ship, and did not want to leave when it was time to draw up the 1)gangplank. The Admiral shook hands with them and Mrs. Popper, and thanked them for having helped to train the 2)extraordinary penguins that were to be a real contribution to science.

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Is there hybridization between 2 species of the same genus in sympatry?——The genetic relationships between Anoplophora glabripennis,Anoplophora chinensis,and putative hybrids

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Insect Science 2024年第2期31卷 633-645页

作者： Haiwen Qin Huachao Xu Arnaud Capron Ilga Porth Mingming Cui Melody A.Keena Xiaofang Deng Juan Shi richard C.Hamelin Sino-French Joint Laboratory for Invasive Forest Pests in Eurasia Department of ForestBejing Forestry UniversityBejingChina Department of Forest and Conservation Sciences The University of British ColumbiaVancouverCanada College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhouChina Department of Wood and Forest Sciences Laval UniversityQuebecCanada 5 Department of AgricultureNorthern Research StationUSDA Forest ServiceHamdenConnecticutUSA Changchun Landscape Plant Conservation Station Bureau of Forestry and Landscaping of ChangchunChangchunChina

Anoplophora glabripennis(Asian longhorn beetle,ALB)and Anoplophora chinensis(Citrus longhorn beetle,CLB)are native forest pests in China;they have become important international quarantine *** are found using the same Salix aureopendula host tree of Cixi,Zhejiang province,*** this host tree,we collected additional beetles that appeared to be morphologically intermediate between ALB and *** using a stereoscope,we observed that there were several bumps on the base of the elytra,which was inconsistent with ALB,which typically has a smooth elytral base,but was more like CLB,which has numerous short tubercles on the elytral *** their sympatry and intermediate morphology,we hypothesized that these may represent ALB×CLB *** studied the genomic profiles for 46 samples(ALB,CLB,and putative hybrids)using genotyping-by-sequencing(GBS)providing a reduced representation of the entire *** principal component analyses on the 163 GBS-derived single nucleotide polymorphism data,we found putative hybrids tightly clustered with ALB,but genetically distinct from the CLB ***,our initial hybrid hypothesis was not supported by genomic ***,while mating experiments between adult ALB and CLB were successful in 4 separate years(2017,2018,2020,and 2021),and oviposition behavior was observed,no progeny was *** employed population genomic analysis and biological hybridization experiments,we conclude that the putative hybrids represent newly discovered morphological variants within *** approach further confirmed the advantage of genome-wide information for Anoplophora species assignment in certain ambiguous classification cases.

关键词： Anoplophora chinensis Anoplophora glabripenni sg enotyping-bysequencing invasive pest mating putative hybrid

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西北太平洋鲐的资源养护和管理研究

中国水产科学 2024年第4期31卷 439-453页

作者：蔡锴周雨霏麻秋云 KINDONG richard 上海海洋大学海洋科学学院浙江大学海洋学院国家远洋渔业工程技术研究中心大洋渔业资源可持续开发教育部重点实验室

鲐(Scomberjaponicus)是西北太平洋海域重要的渔业种类,该渔业涉及多个国家的多种作业方式,渔业形势较复杂,但目前西北太平洋海域尚无基于资源评估的、完善的鲐养护管理措施。本研究使用传统渔业管理方法(资源预测)和较新颖的方法[数据... 详细信息

鲐(Scomberjaponicus)是西北太平洋海域重要的渔业种类,该渔业涉及多个国家的多种作业方式,渔业形势较复杂,但目前西北太平洋海域尚无基于资源评估的、完善的鲐养护管理措施。本研究使用传统渔业管理方法(资源预测)和较新颖的方法[数据有限的渔业管理规程评价(managementstrategyevaluation,MSE)]对鲐的渔业管理进行了研究。在资源预测方法中,通过JABBA和JABBA-Select两个资源评估模型对种群未来的资源动态进行模拟,探讨不同捕捞控制规则(harvest control rules, HCR)下种群的变化。本研究设置了4个HCR,分别以2020年渔获量的0.8～1.4倍,最大可持续产量MSY、B×FMSY和SB×HMSY (分别用于JABBA和JABBA-Select)、历史最高渔获量为总可捕量(totalallowablecatch,TAC),预测2023—2032年间的鲐种群变化。结果显示基于亲体资源量进行研究的JABBA-Select模型,其预测结果相比于JABBA模型略悲观,但都是基于生物学参考点设定的HCR养护和管理效果最好(TAC分别为50～80万t和50～66万t)。MSE则根据设定筛选出12种养护管理效果较好的策略,其中DAAC(消耗率修正后的平均捕获量)与SBT2 (基于资源量和渔获量水平的总可捕量递增矫正法)养护管理效果最好。SBT2求得的TAC (520387 t),与近些年产量及上述HCR的结果较为接近。此外,敏感性分析表明,可捕系数,自然死亡系数和渔获量相关的参数(平均渔获量、渔获量、渔获量参考点)对于养护管理效果的影响最为明显,需要额外关注两者的准确性和精确性。现阶段为确保西北太平洋鲐资源的养护和最佳利用,建议根据B×FMSY或SB×HMSY设定年可捕量,同时基于资源量和渔获量水平进行调整,综合制定管理措施。

关键词：渔业管理有限数据方法种群预测总可捕量

Biofabrication of nanocomposite-based scaffolds containing human bone extracellularmatrix for the differentiation of skeletal stem and progenitor cells

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Bio-Design and Manufacturing 2024年第2期7卷 121-136页

作者： Yang-Hee Kim Janos M.Kanczler Stuart Lanham Andrew Rawlings Marta Roldo Gianluca Tozzi Jonathan I.Dawson Gianluca Cidonio richard O.C.Oreffo Faculty of Medicine Bone and Joint Research GroupCentre for Human DevelopmentStem Cells and RegenerationInstitute of Developmental SciencesUniversity of SouthamptonSouthampton SO166YDUK School of Pharmacy and Biomedical Science University of PortsmouthPortsmouth PO12DTUK School of Engineering Faculty of Engineering and ScienceUniversity of GreenwichGreenwich ME44TBUK Center for Life Nano-and Neuro-Science(CLN2S) Italian Institute of Technology00161 RomeItaly

Autograft or metal implants are routinely used in skeletal ***,they fail to provide long-term clinical resolution,necessitating a functional biomimetic tissue engineering *** use of native human bone tissue for synthesizing a biomimeticmaterial inkfor three-dimensional(3D)bioprintingof skeletal tissueis anattractivestrategyfor ***,human bone extracellular matrix(bone-ECM)offers an exciting potential for the development of an appropriate microenvironment for human bone marrow stromal cells(HBMSCs)to proliferate and differentiate along the osteogenic *** this study,we engineered a novel material ink(LAB)by blending human bone-ECM(B)with nanoclay(L,Laponite®)and alginate(A)polymers using extrusion-based *** inclusion of the nanoﬁller and polymeric material increased the rheology,printability,and drug retention properties and,critically,the preservation of HBMSCs viability upon *** composite of human bone-ECM-based 3D constructs containing vascular endothelial growth factor(VEGF)enhanced vascularization after implantation in an ex vivo chick chorioallantoic membrane(CAM)*** inclusion of bone morphogenetic protein-2(BMP-2)with the HBMSCs further enhanced vascularization and mineralization after only seven *** study demonstrates the synergistic combination of nanoclay with biomimetic materials(alginate and bone-ECM)to support the formation of osteogenic tissue both in vitro and ex vivo and offers a promising novel 3D bioprinting approach to personalized skeletal tissue repair.

关键词： Extracellular matrix Nanoclay Bone 3D bioprinting

In Vivo Improvements in Facial Appearance and in Vitro Changes in Gene Expression Using a Topical Formulation Designed to Repair Environmentally Induced DNA Damage

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Journal of Cosmetics, Dermatological Sciences and Applications 2024年第2期14卷 141-173页

作者： Amaryllis Aganahi richard Parker Yohei Tanaka RATIONALE Kyneton Australia Clinica Tanaka Plastic Reconstructive Surgery and Anti-aging Center Matsumoto Japan

Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept of protecting the skin during the day and repairing cellular damage at night is intuitive, yet specific strategies revolving around combinations of proven reparative active ingredients remain unelucidated. Purpose: To investigate the efficacy of a solar repair Formulation following ultraviolet and environmental exposure in order to improve overall skin health and appearance through three hypotheses: The Formulation increases expression of DNA repair mechanisms markers;The Formulation enhances overall skin appearance through reducing signs of inflammation, elevating hydration, reinforcing skin firmness and amplifying radiance;In-Vivo efficacy test results are aligned with measured gene expression changes. Methods: The Formulation (#6NIC1.V1.1-1) was tested for: In-vitro LDH cytotoxicity activity, In-vitro qPCR gene expression with and without ultraviolet exposure on a reconstructed 3-dimensional skin model, and In-Vivo efficacy study on a panel of 22 participants objectively and subjectively. Results: Skin radiance, firmness, hydration, redness, and inflammation are significantly improved after In-Vivo skin exposure to the Formulation and environmental challenges such as ultraviolet radiation. These outcomes were confirmed by in-vitro genetic testing on a reconstructed human skin model. Conclusion: The studies allowed us to identify and group results in four main skin functions that were significantly enhanced following the application of the Formulation: firmness, hydration, radiance and soothing.

关键词： Photoprotection Photorepair DNA Repair Anti-Photoaging Gene Expression Antioxidant Rejuvenation