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Since their arrival in the 1960s, electronic databases have been an invaluable tool for informetricians. Databases and their
delivery mechanism have provided both the source of raw data, as well as the analytical tools for many informetric studies.
In particular, the citation databases produced by the Institute for Scientific Information have been the key source of data
for a whole range of citation-based research. However, there are also many problems and challenges associated with the use
of online databases. Most of the problems arise because databases are designed primarily for information retrieval purposes,
and informetric studies represent only a secondary use of the systems. The sorts of problems encountered by informetricians
include: errors or inconsistency in the data itself; problems with the coverage, overlap and changeability of the databases;
as well as problems and limitations in the tools provided by the database hosts such as DIALOG. For some informetric studies,
the only viable solution to these problems is to download the data and perform offline correction and data analysis.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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It is shown how Bradford curves, i.e. cumulative rank-frequency functions, as used in informetrics, can describe the fragment size distribution of percolation models. This interesting fact is explained by arguing that some aspects of percolation can be interpreted as a model for the success-breeds-success or cumulative advantage phenomenon. We claim, moreover, that the percolation model can be used as a model to study (generalised) bibliographies. This article shows how ideas and techniques studied and developed in informetrics and scientometrics can successfully be applied in other fields of science, and vice versa. 相似文献
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Jafar Mahmoudi 《Quality and Reliability Engineering International》2021,37(8):3297-3313
Proper performance evaluation of subsea system components is of high significance for reliable operation and remote monitoring or the replacement of the components before the occurrence of any failure. As a part of subsea systems, subsea control system (SCS) plays a key role in accomplishing a reliable performance. Hence, achieving knowledge of the components’ failure rates is highly important in the safety analysis of SCS. To the author's knowledge, limited work is done on the safety analysis of SCS using failure rates for a multitude of components. Also, the number of research papers that are based on industrial works is restricted. Hence, this paper aims to provide a noticeable contribution in fulfilling the referred gap. For this purpose, a safety integrity-level (SIL) analysis is proposed based on a typical OREDA database. In the implementation of the proposed SIL, a failure mode classification table is provided for a selection of SCS components. This is followed by the estimation of several parameters, such as the total time in service, as well as obtaining the values of critical failure rates. The analysis indicates that signal failure is the failure mode occurring more than the other ones. Also, the subsea electronic module yields the highest value of critical failure rates. Besides, a comparison of parameter values is provided for two different versions of the utilized database. 相似文献
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Patrick Georges 《Scientometrics》2017,112(1):21-53
This paper proposes a statistical analysis that captures similarities and differences between classical music composers with the eventual aim to understand why particular composers ‘sound’ different even if their ‘lineages’ (influences network) are similar or why they ‘sound’ alike if their ‘lineages’ are different. In order to do this we use statistical methods and measures of association or similarity (based on presence/absence of traits such as specific ‘ecological’ characteristics and personal musical influences) that have been developed in biosystematics, scientometrics, and bibliographic coupling. This paper also represents a first step towards a more ambitious goal of developing an evolutionary model of Western classical music. 相似文献
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音乐信号分析中常数Q变换的性能研究 总被引:1,自引:0,他引:1
由于采用指数分布的频域采样点,常数Q变换(ConstantQTransform—CQT)在音乐信号的音调分析中有着独特的优点。但是常数Q变换的性能究竟如何,还需进行多方面的研究,以便能开发其潜力、完善其不足。对于两种CQT定义下的频率估计准确性问题进行了讨论,给出了频率估计误差的计算公式和给定音节频率分辨率下CQT窗函数长度应满足的关系;通过实验研究了CQT和DFT在多音阶频率检测时的性能以及窗函数对CQT性能的影响。通过和DFT的比较,可以看到CQT在某些方面具有比DFT更好的特性。对于CQT的一些局限性文中也作了简单的评述。 相似文献
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数据库是软件的重要部分,甚至可以说是整个系统的核心,对于一些系统来说,数据库作为储存所有重要数据的地方,如果这个部分出了问题,导致储存的数据丢失,无论是企业还是政府部门等,都是非常重大的损失,如果要想避免这种现象出现,就应该最大程度的保证数据库软件的安全性和稳定性,本文根据数据库软件的特点,对数据库软件的测试和调试进行深入的分析。 相似文献
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Fragmentation at the Xxx-Pro bond was analyzed for a group of peptide mass spectra that were acquired in a Finnigan ion trap mass spectrometer and were generated from proteins digested by enzymes and identified by the Sequest algorithm. Cleavage with formation of a + b + y ions occurred more readily at the Xxx-Pro bond than at other locations in these peptides, and the importance of this cleavage varied by the identity of Xxx. The most abundant Xxx-Pro relative bond cleavage ratios were observed when Xxx was Val, His, Asp, Ile, and Leu, whereas the least abundant cleavage ratios occurred when Xxx was Gly or Pro. Rationalization for these cleavage ratios at Xxx-Pro may include contribution of the Asp or His side chain to enhanced cleavage or the conformation of Pro, Gly, and the aliphatic residues Val, Ile, and Leu at the Xxx location in the Xxx-Pro bond. Although unusual fragmentation behavior has been noted for Pro-containing peptides, this analysis suggests that fragmentation at the Xxx-Pro bond is predictable and that this information may be used to improve the identification of proteins if it is incorporated into peptide sequencing algorithms. 相似文献
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We present a statistical analysis of a large set of absorption spectra of phytoplankton, measured in natural samples collected from ocean water, in conjunction with detailed pigment concentrations. We processed the absorption spectra with a sophisticated neural network method suitable for classifying complex phenomena, the so-called self-organizing maps (SOM) proposed by Kohonen [Kohonen, Self Organizing Maps (Springer-Verlag, 1984)]. The aim was to compress the information embedded in the data set into a reduced number of classes characterizing the data set, which facilitates the analysis. By processing the absorption spectra, we were able to retrieve well-known relationships among pigment concentrations and to display them on maps to facilitate their interpretation. We then showed that the SOM enabled us to extract pertinent information about pigment concentrations normalized to chlorophyll a. We were able to propose new relationships between the fucoxanthin/Tchl-a ratio and the derivative of the absorption spectrum at 510 nm and between the Tchl-b/Tchl-a ratio and the derivative at 640 nm. Finally, we demonstrate the possibility of inverting the absorption spectrum to retrieve the pigment concentrations with better accuracy than a regression analysis using the Tchl-a concentration derived from the absorption at 440 nm. We also discuss the data coding used to build the self-organizing map. This methodology is very general and can be used to analyze a large class of complex data. 相似文献
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Anna M. Ferrante Diana L. Rosman Matthew W. Knuiman 《Accident; analysis and prevention》1993,25(6):659-665
In order to effectively examine possible causes and determinants of road trauma, reliable informa- tion on the participants, circumstances, and resultant injuries and deaths must be available. Characteristics of participants (persons and vehicles) and the circumstances of road accidents are routinely collected by police and road authorities, whereas details of the injuries and medical care provided to casualties are collected by hospital and ambulance services. A road injury database, linking data collected by the Health, Police, and Main Roads Departments of the Government of Western Australia with records of the St. John Ambulance Association and the Death Register, has been established. This paper describes the procedures used to link the various sources of data and discusses the design, construction, and quality of the resultant relational database. 相似文献
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汽车发动机远程故障诊断数据库系统设计分析 总被引:2,自引:0,他引:2
利用数据库技术建立汽车发动机远程故障诊断系统,重点分析了远程故障诊断中心发动机诊断数据库和标准数据库等的设计思路,介绍了系统的结构模型、数据库访问、数据库实现、数据库安全等技术,对汽车发动机故障远程诊断系统的建立和开发具有指导意义. 相似文献
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Scientometrics - This paper applies clustering techniques and multi-dimensional scaling (MDS) analysis to a 500?×?500 composers’ similarity/distance matrix. The objective is... 相似文献
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The development is described of a novel Probabilistic Fracture Mechanics (PFM) code based on the three-dimensional J-integral database, giving so-called fully plastic solutions. An efficient technique for the evaluation of leak and break probabilities is also utilized, based on the Stratified sampling Monte Carlo simulation (SMC).
The outline of the present PFM code is described, and the J-integral database and the numerical technique are presented. Nonlinear effects of materials on failure probabilities are discussed through the analysis of a surface cracked structure subjected to cyclic tension. 相似文献
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van Dijk JW 《Radiation protection dosimetry》2007,123(3):318-322
Maintaining the integrity of the databases is one of the important aspects of quality assurance at individual monitoring services and national dose registers. This paper presents a method for finding and preventing the occurrence of duplicate entries in the databases that can occur, e.g. because of a variable spelling or misspelling of the name. The method is based on bi-gram text analysis techniques. The methods can also be used for retrieving dose data in historical databases in the framework of dose reconstruction efforts of persons of whom the spelling of the name as originally entered, possibly decades ago, is uncertain. 相似文献
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To the best of our knowledge, there is no work that has focused on analysing the development of the scientific production on women, peace and security. The main objective of this paper is to cover this research gap through a bibliometric analysis, that covers 95 years (1918–2013), of articles published in peer-reviewed journals extracted from the SCOPUS database. Bibliometric indicators and laws have been applied to better understand the patterns that govern the scientific literature on this realm. A gender perspective has also been implemented in the analysis. The analysis provides quantitative results based on 321 articles published by 478 authors in 210 scientific journals. The data showed the high dispersion of the literature, both in terms of authors and journals focused on the topic, and a low level of collaboration among both authors and institutions. Regarding the research topic, half of the papers were related to the impact of conflict on civilians and civil society. The implementation of a gender perspective shows that most of the first, second and third authors of the papers are women. In terms of methodologies, qualitative methodologies are the most relevant and women are more prolific applying these methodology. In terms of geographical region of the research, most of the studies have been performed by authors from institutions in Anglo-Saxon countries, and most of the fieldwork has been focused on the United States and the main areas of conflict in the world throughout history. Finally, important research opportunities are identified. 相似文献
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The development and demise of a cataract surgery database 总被引:2,自引:0,他引:2
BACKGROUND: The American Academy of Ophthalmology (AAO; San Francisco) launched a national eye care outcomes initiative in 1996, in response to strong interest by third-party payers and managed care in performance measurement and outcomes. The AAO's outcomes initiative NEON (National Eyecare Outcomes Network) began with the design and launch of a prospective observational registry of patients undergoing cataract surgery. METHODS: Participants submitted a common set of data regarding patients' demographics, preoperative ophthalmologic history, physical exam, test results, functional status and symptoms, intraoperative procedures and events, and postoperative outcomes for all patients undergoing first or second eye cataract surgery. RESULTS: Between January 1, 1996, and March 30, 2001, a total of 249 ophthalmologists submitted data on 17,876 patients undergoing first or second eye surgery. All preoperative, intraoperative, and postoperative clinical data forms were submitted for 9,937 patients (55.7%). After surgery, 93% of patients achieved a best corrected visual acuity of 20/40, 89% improved their visual functioning, and 92% experienced fewer cataract-related symptoms. DISCUSSION: At the end of March 2001, NEON was discontinued because of a lack of participation and demand by members or third parties for this information. The momentum for accountability and performance measures never quite materialized into advantages for contracting for physicians or requirements by payers. In the future, more scientific evidence regarding the validity and meaning of outcome measures and differences in measurements, investment in health information technology infrastructure, use of technology to collect information at the point of care, and incentives favoring data collection and analysis will be needed to pave the way for renewed interest in outcomes. 相似文献