Results 81 to 90 of about 34,740 (207)
Distribution, scale, and drivers of mass mortality events in Europe's freshwater bivalves
Conservation Biology, EarlyView.Abstract Mass mortality events (MMEs) are decimating populations and compromising key ecosystem functions around the globe. One taxon particularly vulnerable to MMEs is freshwater bivalve mollusks. This group has important ecosystem engineering capacities and includes highly threatened and highly invasive taxa.
Daniel A. Cossey +39 more
wiley +1 more source
Study on Parallel Learning Algorithm of Gradient Boosting Decision Tree [PDF]
, 2016 GBDT(GradientBoostingDecisionTree)是一个应用广泛、效果好的监督式机器学习模型。它于2001年由Friedman提出，由决策树(DecisionTree)和梯度提升(GradientBoosting)组合而成。它在实践中被证明是一个很高效的模型，被广泛应用于搜索排序，广告点击率预测等，给工业界带来了巨大的效果提升和收益。随着互联网时代的到来，更多的数据可以被获取到。在机器学习中，更多的数据也意味着更好的效果，所以，用大数据来训练机器学习模型是很有必要的 ...
柯国霖
core
The collective application of shorebird tracking data to conservation
Conservation Biology, EarlyView.Abstract Addressing urgent conservation issues, such as the drastic declines of North American migratory birds, requires creative, evidence‐based, efficient, and collaborative approaches. The abundance of over 50% of monitored North American shorebird populations has declined by over 50% since 1980. To address these declines, we developed a partnership
Autumn‐Lynn Harrison +71 more
wiley +1 more source
大数据随着测量技术和数值模拟技术的发展，数据驱动的湍流研究成为该领域的新研究方法。我国已建立了多个风洞实验室和多个超算中心来模拟湍流，这些研究积累了大量的湍流数据，但是国内没有集中的湍流数据管理平台，耗资巨大的实验和仿真数据难以实现交流和共享。湍流数据具有数据量大、维度高、精度高和多源异构等特点，其存储、访问与管理存在数据集成困难、数据访问低效和存储效率低等问题。设计了一个面向航空、航天和航海典型流动问题的湍流大数据分布式存储系统TDFS。结合湍流大数据的访问特点 ...
程文迪, 张晓, 潘兆辉, 赵友军, 孙晨光, 单学强, 金雨展, 赵晓南
doaj +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2019 随着浙江省水情信息化的不断推进，水情数据种类、结构和数据量不断丰富和发展，传统的单结构化数据存储管理方式已不适合当前信息化社会的应用和服务需求。本研究采用先进的分布式数据采集、智能数据过滤、大数据存储等技术，构建基于大数据云平台技术的浙江省水情云数据中心，对各类分散的多源异构数据进行全面整合。实现了水情大数据的质量管控、深度挖掘和高效共享，丰富了水情信息的资源样本，拓展了服务深度和广度，提升了数据挖掘的服务效率和能力，为水利业务和事务的现代化发展奠定了坚实的基础。
QIUChao(邱超) +2 more
doaj +1 more source
Research of KNN Graph Algorithm Parallelization based on Spark and Its Application [PDF]
, 2016 近些年来，随着计算机科学技术的迅速发展，越来越多的海量数据信息在许多行业中随之产生，海量数据对数据处理的效率提出了极大的挑战。同时在此背景下分布式计算也得到了大力发展，Hadoop使得用户可以进行超大数据集的分析，但是其基于磁盘的MapReduce的计算严重影响了计算性能，而Spark引入RDD(ResilientDistributedDatasets)基于内存计算迎合了广大用户的需求，极大提高了分布式并行计算的效率。虽然在众多大数据工具中，Spark得到了很大的关注，但是Spark还不是十分完善 ...
汪龙宝
core
How much biotic nativeness matters across human demographic groups
Conservation Biology, EarlyView.Abstract Many central concepts of conservation biology—such as nativeness—are structured by ecological and social factors. However, the social consequences of using these concepts to make conservation decisions remain inadequately understood. Some researchers argue that nativeness, rather than acting as an objective proxy for important ecological ...
Harold N. Eyster, Rachelle K. Gould
wiley +1 more source
Design and Implementation of Public Security Intelligence Search-Platform Based on Big Data Technology [PDF]
, 2015 公安信息化的高速发展积累了丰富的业务数据，种类不断增加、结构不断异化、总量不断增长，截至2014年底，全国公安机关掌握的数据资源已达100多类上千亿条,信息数据已成为继警力资源、装备资源之后的新一类核心资源。搜索是公安信息获取和进行研判的基础手段。传统的全文搜索系统存在大量结果数据“堆积”、再次筛查工作量大、目标结果无法精准定位，使用效率低下等问题。利用分布式计算架构，融合了SolrCloud、Zookeeper、高速缓存等技术手段，以人、车、案为对象重组数据，采用智能分析、对象全景档案等手段 ...
何志昭
core
Informing spatial conservation prioritization with species’ traits
Conservation Biology, EarlyView.Abstract New Guinea, the most botanically diverse island on the planet, is the location for one of the boldest conservation initiatives. The Manokwari Declaration aims to achieve 70% conservation designation for the Bird's Head Peninsula. This is 40% higher than the 2022 Global Biodiversity Framework target.
Liam A. Trethowan +27 more
wiley +1 more source
Differences in characteristics between naturalized threatened plants and other threatened plants
Conservation Biology, EarlyView.Abstract Many non‐native plant species introduced by humans have become naturalized. At the same time many species are threatened in their native range. However, the number of plant species threatened in their native range that are naturalized elsewhere remains unknown.
Weihan Zhao +10 more
wiley +1 more source