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关键词： Algorithms   Applied mathematics   Behavior   Biology and life sciences   Cognition   Cognitive psychology   Cognitive science   Decision making   Engineering and technology   Game theory   Games   Mathematical and statistical techniques   Mathematical functions   Mathematics   Neuroscience   Number theory   Optimization   Physical sciences   Psychology   Real numbers   Recreation   Research and analysis methods   Research Article   Signal bandwidth   Signal processing   Simulation and modeling   Social sciences   Time domain analysis  

摘要： The increasing demand for network applications, such as teleconferencing, multimedia messaging and mobile TV, which have diverse requirements, has resulted in the introduction of Long Term Evolution (LTE) by the Third Generation Partnership Project (3GPP). LTE networks implement resource allocation algorithms to distribute radio resource to satisfy the bandwidth and delay requirements of users. However, the scheduling algorithm problem of distributing radio resources to users is not well defined in the LTE standard and thus considerably affects transmission order. Furthermore, the existing radio resource algorithm suffers from performance degradation under prioritised conditions because of the minimum data rate used to determine the transmission order. In this work, a novel downlink resource allocation algorithm that uses quality of service (QoS) requirements and channel conditions to address performance degradation is proposed. The new algorithm is formulated as an optimisation problem where network resources are allocated according to users' priority, whereas the scheduling algorithm decides on the basis of users' channel status to satisfy the demands of QoS. Simulation is used to evaluate the performance of the proposed algorithm, and results demonstrate that it performs better than do all other algorithms according to the measured metrics.

关键词： detrital fingerprint   terrane analysis   zircon   provenance   paleodrainage   New Caledonia  

摘要： Archean and Proterozoic zircon grains are commonly found in much younger clastic sedimentary rocks, but the geological significance of these ages is often overlooked. Here we demonstrate that the age spectra of early Precambrian sedimentary recycled and/or magmatic inherited zircon grains form a unique pattern (detrital fingerprint) that can be used to test connectivity or indicate sediment recycling between terranes. Using the island of New Caledonia as a case study, we compiled 212 (published and new) concordant ages that are older than 1400 Ma from samples that represent contemporary sediments (this study), an allochthonous nappe sequence, and Paleozoic-Mesozoic metasedimentary rocks. By comparing these data with an equivalent dataset of Precambrian zircon ages (n > 1400 Ma = 2636) from Paleozoic eastern Australia (Tasmanides), we test connectivity and disjunction of New Caledonia with crustal domains within the Tasmanides. Results show that the early Precambrian detrital fingerprint of New Caledonia is similar to the southern Tasmanides (and possibly East Antarctica), but is significantly different than the detrital fingerprint of the northern Tasmanides. The results thus provide an independent constraint on the origin of the late Paleozoic to early Mesozoic New Caledonian continental basement, shedding new light on the tectonic evolution of the southwestern Pacific region, and demonstrate the capabilities of the methodological approach. (C) 2018 Elsevier B.V. All rights reserved.

关键词： 中华医学会   标注   数   杂志   出版物   国际标准   条形码   信息  

摘要： 数字对象唯一标识符(digital Obiect identmer,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。

关键词： 标注   数   出版物   国际标准   条形码   信息   互联网  

摘要： 数字对象唯一标识符(digital object identifier,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。

关键词： Adult congenital heart disease   Diagnostic code   Nomenclature   Electronic medical records  

摘要： Background. - The content of electronic medical records (EMRs) encompasses both structured data, such as billing codes, and unstructured data, including free-text reports. Epidemiological and clinical research into adult congenital heart disease (ACHD) increasingly relies on administrative claim data using the International Classification of Diseases (9th revision) (ICD-9). In France, administrative databases use ICD-10, the reliability of which is largely unknown in this context. Aims. - To assess the accuracy of ICD-10 codes retrieved from administrative claim data in the identification and classification of ACHD. Methods. - We randomly included 6000 patients hospitalized at least once in 2000-2014 in a cardiology department with a dedicated specialized ACHD Unit. For each patient, the clinical diagnosis extracted from the EMR was compared with the assigned ICD-10 codes. Performance of ICD-10 codes in the identification and classification of ACHD was assessed by estimating sensitivity, specificity and positive predictive value. Results. - Among the 6000 patients included, 780 (13%) patients with ACHD were manually identified from EMRs (107,092 documents). ICD-10 codes correctly categorized 629 as having ACHD (sensitivity 0.81, 95% confidence interval 0.78-0.83), with a specificity of 0.99 (95% confidence interval 0.99-1). The performance of ICD-10 codes in correctly categorizing the ACHD defect subtype depended on the defect, with sensitivity ranging from 0 (e.g. unspecified congenital malformation of tricuspid valve) to 1 (e.g. common arterial trunk), and specificity ranging from 0.99 to 1. Conclusions. - Administrative data using ICD-10 codes is a precise tool for detecting ACHD, and may be used to establish a national cohort. Mining free-text reports in addition to coded administrative data may offset the lack of sensitivity and accuracy when describing the spectrum of congenital heart disease using ICD-10 codes. (C) 2018 Published by Elsevier Masson SAS.

标准号: BS ISO 15511-2019

摘要： This document specifies the International Standard identifier for libraries and related organizations (ISIL), which comprises a set of standard identifiers used for the unique identification of libraries and related organizations such as museums and archives with a minimum impact on already existing *** ISIL identifies an organization, i.e. a library or a related organization, or one of its subordinate units, which is responsible for an action or service in an informational environment (e.g. creation of machine-readable information). It can be used to identify the originator or holder of a resource (e.g. library material or a collection in an archive). The ISIL is intended for use by libraries and related organizations such as museums and archives and agencies doing business or interacting with these organizations (e.g. suppliers, publishers, and government institutions). An ISIL identifies an organization or one of its subordinate units throughout its life. In some cases, such as when an organization has undergone a significant administrative change (e.g. a merger with another organization), particularly one that results in a name change, a new ISIL can be *** this document allows the use of existing codes to be incorporated into the ISIL, it is possible that a given organization can have more than one ISIL. However, it is the intention of this document to minimize the number of *** library or related organization, administrative unit or subordinate unit, acting autonomously, can be allocated an *** ISIL is not intended to be used to classify organizations or their services and holdings.

关键词： DOI   标识符   基金会   《机电产品开发与创新》   万方数据  

摘要： 由北京万方数据股份有限公司运行的中文DOI■注册机构是IDF(国际DOI基金会)正式授权的DOI注册机构,负责开展各种中文数字资源的DOI注册及服务。为了促进中国期刊的全球标准化推广工作,促进中文学术信息的网络传播与利用、提高中国期刊的全球影响力。我刊于2009年5月与万方数据签约注册DOI。1 DOI介绍1.1 DOI是一种标识DOI为数字信息提供了全球唯一的身份标识,就如同出版物贴上了条形码一样,无论走到哪里都有踪迹可寻。因而DOI被形象地称为数字资源的条形码或身份证。方便了计算机的互操作,并可以实现永久指向、动态维护。DOI标识符由两部分组

关键词： DOI   标识符   期刊论文   万方数据  

摘要： 由北京万方数据股份有限公司运行的中文DOI;注册机构是IDF（国际DOI基金会）正式授权的DOI注册机构,负责开展各种中文数字资源的DOI注册及服务。为了促进中国期刊的全球标准化推广工作,促进中文学术信息的网络传播与利用、提高中国期刊的全球影响力。我刊于2009年5月与万方数据签约注册DOI。

关键词： academic identities   authority records   discoverability   identity management   scholarly profiles   search engine indexing   search engine optimization   social media  

摘要： Information about faculty and their publications can be found in library databases such as the Library of Congress Name Authority File, VIAF, WorldCat, and institutional repositories;in identifier registries such as ORCID and ISNI;and on academic social networking sites such as Academia, Google Scholar, and ResearchGate, but the way search engines use such identifiers and profiles is unclear. Therefore, researchers at a large comprehensive university conducted several rounds of web searching before and after the creation and modification of faculty authority records. The sample consisted of 24 faculty and the 35 publications associated with their authorities. The researchers searched for the faculty and their publications on the social networking and identity websites directly, and then used Google, Bing, and Google Scholar to record which of the faculty members' profiles and publications were found within the top 50 results. Faculty with more profiles were more visible in search engine results, and faculty with authority records ranked more highly in Google. Results related to publication discovery and ranking were more inconclusive, but revealed clear differences between search tools. The implications of this exploratory research can support educational efforts about academic identities and scholarly profiles, begin a research agenda, and inform methodological development surrounding the influence of identity records and academic social networking profiles on web visibility.

关键词： Hu矩   标识符识别   路径跟踪   模糊控制  

摘要： 在工业4.0和中国制造2025政策的推动下,国内外高校和企业逐渐加大对机器人的研究力度。随着计算机和传感器等软硬件性能的提升,移动机器人的功能逐步趋向全方位化和全自动化。视觉导航技术作为引导机器人工作的“眼睛”一直是机器人导引研究的热点,其关键核心为路径识别技术。提高移动机器人的路径识别技术水平和路径跟踪控制技术水平有利于机器人实现更高精度的运动,为移动机器人跟踪更复杂的工作路线以及完成更高难度系数的任务建立基础。本文以视觉导引移动机器人作为研究对象,设计并搭建出视觉导引移动机器人系统。建立相机标定模型并对相机进行标定,完成失真图像的矫正过程。对导航带图像和标识符图像的预处理算法进行研究,包括灰度化、滤波、分割、形态学增强、边缘检测和感兴趣区域选取等,提出轮廓边缘扫描法提取边缘线,并通过最小二乘法拟合中心线;使用改进后的Hu矩算法提取标识符特征,并用机器学习算法进行标识符识别。建立视觉导引移动机器人的运动学模型,分析两驱动轮位置偏差和角度偏差与控制电压之间的数学关系,获得路径跟踪控制系统方程。基于模糊控制方法,对运动学模型设计出一种模糊控制器,并与经典PID控制器进行比较。本文对视觉导引移动机器人进行测试,验证视觉图像处理算法精度和实时性以及路径跟踪控制器的纠偏性能。测试结果表明:(1)与传统算法相比,本文提出的轮廓边缘扫描法结合最小二乘法拟合中心线耗时22ms,改进后的Hu矩算法处理时间为2.49ms,比原Hu算法的4.81ms短,且精度更高。改进的算法性能满足视觉导引移动机器人系统的实时性要求和精度要求。(2)本文基于模糊原理设计的路径跟踪控制器可以准确快速地跟踪直线型、圆弧型和混合型线路,可以用于不同速度移动的机器人系统,角度偏差控制在±4°,位置偏差控制在±6mm。表明控制器的控制性能好,鲁棒性强,具有较高的实际工程应用价值。