DUCR: Distributed unequal cluster‐based routing algorithm for heterogeneous wireless sensor networks

Designing energy efficient communication protocols for wireless sensor networks (WSNs) to conserve the sensors' energy is one of the prime concerns. Clustering in WSNs significantly reduces the energy consumption in which the nodes are organized in clusters, each having a cluster head (CH). The CHs collect data from their cluster members and transmit it to the base station via a single or multihop communication. The main issue in such mechanism is how to associate the nodes to CHs and how to route the data of CHs so that the overall load on CHs are balanced. Since the sensor nodes operate autonomously, the methods designed for WSNs should be of distributed nature, i.e., each node should run it using its local information only. Considering these issues, we propose a distributed multiobjective‐based clustering method to assign a sensor node to appropriate CH so that the load is balanced. We also propose an energy‐efficient routing algorithm to balance the relay load among the CHs. In case any CH dies, we propose a recovery strategy for its cluster members. All our proposed methods are completely distributed in nature. Simulation results demonstrate the efficiency of the proposed algorithm in terms of energy consumption and hence prolonging the network lifetime. We compare the performance of the proposed algorithm with some existing algorithms in terms of number of alive nodes, network lifetime, energy efficiency, and energy population.     

热点感知的无线传感器网络数据存储策略

针对基于地理哈希表(GHT,Geographic Hash Table)的传感器网络数据中心存储(DCS,Data Centric Stora-ge)机制的热点问题,提出了能量有效的热点感知数据存储策略SASS (hotSpot-Aware data Storage Strategy),对GHT的路由策略进行改进,以减少边界模式引起的能量消耗,并利用邻居节点动态地扩展存储空间。仿真结果表明,与现有存储策略相比,SASS能有效减少因存储资源限制引起的数据丢失,并减轻热点区域节点的通信负载。     

企业信息分布式存储的热点处理策略

为解决企业信息分布式存储中因局部访问过热而导致的一系列问题，提出了新型的分布式存储热点处理策略。该策略将存储对象的热度划分为直接热度、内部热度和间接热度，并且根据该划分提出不同的热点处理子策略，建立了一个企业分布式存储系统的热点处理模型。根据该模型及策略，给出了与之对应的算法，包括信息收集、选择、协商以及扩散4个子算法。分析和应用结果表明，该策略能够减少内部通信量、缩短用户请求延迟、提高系统有效用户。最后，采用该策略的实例验证了它的有效性。     

文献计量与知识图谱视角下中外家具设计的比较研究

目的 回顾国内外关于家具设计研究的进展与热点前沿。方法 基于文献计量与知识图谱方法,运用CiteSpace和Bibexcel软件,梳理总结3 156篇知网中文文献和341篇Web of Science核心合集英文文献。结果 国内外家具设计领域在学科基础、研究力量、前沿趋势之间存在差异。结论 国外家具设计研究文献数量稳定,国内则发展迅速且在数量上有一定的优势。国内发文高产期刊集中在轻工业手工业领域,而国外则主要聚焦建筑领域。国内外研究团队均趋于分散,机构间相互联系较少。国外家具设计研究具有较强的现实导向性,体现在人的因素和仿生生态等方面。国内研究则较为注重家具设计理论,以及产业、学科专业建构的系统性。期望未来我国家具设计研究的发展能进一步突出核心期刊和高产机构的先锋作用,加强国内和国外的合作交流,继续立足国家战略,服务人民需求。     

Data-Driven Approaches for Spatio-Temporal Analysis: A Survey of the State-of-the-Arts

With the advancement of telecommunications, sensor networks, crowd sourcing, and remote sensing technology in present days, there has been a tremendous growth in the volume of data having both spatial and temporal references. This huge volume of available spatio-temporal (ST) data along with the recent development of machine learning and computational intelligence techniques has incited the current research concerns in developing various data-driven models for extracting useful and interesting patterns, relationships, and knowledge embedded in such large ST datasets. In this survey, we provide a structured and systematic overview of the research on data-driven approaches for spatio-temporal data analysis. The focus is on outlining various state-of-the-art spatio-temporal data mining techniques, and their applications in various domains. We start with a brief overview of spatio-temporal data and various challenges in analyzing such data, and conclude by listing the current trends and future scopes of research in this multi-disciplinary area. Compared with other relevant surveys, this paper provides a comprehensive coverage of the techniques from both computational/methodological and application perspectives. We anticipate that the present survey will help in better understanding various directions in which research has been conducted to explore data-driven modeling for analyzing spatio-temporal data.

     

低碳园林研究综述及研究热点分析

研究阐述低碳园林在国内外的研究方向和研究热点,探讨低碳园林的研究发展过程及知识框架,为低碳园林领域的进一步研究与应用设计方法提供建议与参考.通过检索中国知网CNKI数据库和Web of Science核心合集数据库中2011—?2021年的低碳园林领域相关文献.中文文献检索词为"低碳园林OR低碳景观",外文文献检索词为...     

新世纪大西洋两岸深水勘探总结和启示浅析

新世纪大西洋两岸深水勘探成为勘探热点和高储量发现区.通过概述该时期勘探历程和成果,总结了大西洋两岸勘探得失成败,并分析了不同类型公司成败的主要原因,认为持续地质研究积累和技术创新是石油巨头保持成功的基础,公司策略、规模、风险识别和抵御风险的能力是保证独立石油公司生存与发展的关键.未来中南大西洋盐下碳酸盐岩、中大西洋两岸...     

浅析我国纺织专利技术发展现状

本文采用IPC分类法统计了纺织各分支领域的专利申请量,分析了纺织领域专利的发展现状和趋势,判断出现阶段我国纺织技术的研发重点、热点。在此基础上,结合市场情况展望了未来纺织技术发展的热点领域。     

煤层气产业发展研究的现状与展望

运用文献计量法对中国煤层气产业发展研究的文献数量和归属学科、重要作者、权威机构进行统计分析;借助Cite Space知识可视化软件探测出煤层气产业发展研究的主题热点,包括煤层气产业,开发利用,煤层气资源,勘探开发,非常规天然气,洁净煤技术,并得到其演进历程及7个主题聚类群。研究认为煤层气勘探开发技术创新研究仍将是煤层气产业发展研究的重点,协调发展是主要方向,以资源综合利用,安全生产和保护环境为目标的绿色开放发展将成为研究新趋向。     

我国制浆造纸技术发展的知识图谱构建与分析

本课题通过分析我国制浆造纸业的发展历程,大致勾勒出我国造纸业近40年的发展脉络,总结出不同时段的研究热点和发展趋势,为该领域的后续研究提供参考。通过一定的筛选条件选择CNKI数据库中近40年发表在《中国造纸》《中国造纸学报》等5本制浆造纸期刊的18073篇有效文献,利用可视化分析软件CiteSpace绘制我国制浆造纸研究的科学知识图谱,分时段对研究热点和研究前沿进行分析。分析结果表明,卡伯值、表面施胶、漂白、结构、打浆、废纸浆、新闻纸、造纸废水等是高频关键词,代表我国制浆造纸研究的热点问题。通过突变词分析,对我国造纸业近40年的发展前沿按4个时间段依次分析,解析了我国制浆造纸技术发展的研究方向从造纸原料、设备、工艺向纸张性能、环境保护、新型材料的总体转变趋势。从整体上看,我国现代造纸工业虽起步较晚,但发展迅速,已经达到了较为成熟的阶段;环境保护已成为制浆造纸发展的必然要求;新型材料的开发和新型技术的应用逐渐展开。