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51.
Given the growing use of impact metrics in the evaluation of scholars, journals, academic institutions, and even countries, there is a critical need for means to compare scientific impact across disciplinary boundaries. Unfortunately, citation-based metrics are strongly biased by diverse field sizes and publication and citation practices. As a result, we have witnessed an explosion in the number of newly proposed metrics that claim to be “universal.” However, there is currently no way to objectively assess whether a normalized metric can actually compensate for disciplinary bias. We introduce a new method to assess the universality of any scholarly impact metric, and apply it to evaluate a number of established metrics. We also define a very simple new metric hs, which proves to be universal, thus allowing to compare the impact of scholars across scientific disciplines. These results move us closer to a formal methodology in the measure of scholarly impact.  相似文献   
52.
The article examines academics attitude towards e-journal use. A well structured questionnaire was designed to elicit the opinions of the users. Responses were gathered from 542 faculty members of five universities. The results of the study showed that the characteristics that affect the choice of e-format over print in order of preference are ‘faster access’, ‘available from desktop’, ‘convenience’, ‘remote access’, ‘timeliness’, ‘available at all times’, ‘hyperlinks’, ‘multi-user access’, ‘currency of information’, ‘inclusion of audio–video material’, ‘interactivity’ and ‘animation of graphics’. The characteristics that affect the choice of print format over electronic in order of priority are ‘physical comfort’, ‘portability’, ‘ability to underline’, ‘familiarity with format’ and ‘ability to browse’. A majority of the teachers use e-journals for ‘research’, ‘teaching’, ‘writing reports’, ‘current awareness’, ‘background research’ and ‘internal/external presentations’. The problems faced in accessing e-journals are ‘access difficulties’, ‘discomfort of reading from computer screen’, ‘lack of IT knowledge/skill’, ‘information overload’ etc. A majority of the teachers want future e-journals to have features such as ‘full text index of every article’, ‘searching capability across a wide range of journal articles’, ‘searching capability within an article, display relationship between a wide range of works’ and ‘links to multimedia files’, etc. On the basis of the findings, some suggestions are made for maximizing the use of e-journals.  相似文献   
53.
Library operation and management requires the performance of a number of repetitive, painstaking, labour- and time-intensive activities. Hence, in order to increase efficiency and effectiveness, many libraries are moving towards automation of the majority of their activities. Libraries are deploying Radio Frequency Identification (RFID) technology as a substitute for barcode systems for item identification and tracking, and this ultimately enables the automation of the majority of their processes. It is apparent from the available literature that research on RFID-related issues is largely concentrated on technical, organizational and implementation aspects, and less attention has been paid to understanding the use and user-satisfaction aspects. Therefore, this article aims to understand factors affecting the use of RFID systems and user satisfaction in a library context by empirically testing relevant constructs from DeLone and McLean's IS Success Model. A questionnaire-based survey was employed to collect data from a total of 181 respondents, who were all active users of an RFID-based library system. The findings from this study suggest that factors like system quality, use and user satisfaction positively influence consumer attitudes towards RFID-enabled services. The concluding section outlines salient points and briefly describes the associated limitations of this research, along with suggestions for future research directions.  相似文献   
54.
The possibilities of quantitative student observations during the transit of Venus, using simple equipment, are discussed. The equipment could also be used for safe observations of the Sun during eclipses, transits of Mercury as also for daily observations of sunspots. The annual variation in the angular diameter of the Sun as it passes from aphelion to perihelion and so on, could be measured with this simple equipment. School and college astronomy clubs would find it very useful to use this equipment for daytime astronomy activities and learning-oriented projects.  相似文献   
55.
While various research studies have focused on antecedents and consequences of student satisfaction, few studies have done so in the Gulf region. The objective of the present study was therefore to design and empirically examine a model of student satisfaction in a private university in the Gulf region that operates in a high-technology-enabled environment. Based on a literature review and conducted focus groups, draft measures for the study constructs were developed. Data were collected from 217 students and an exploratory factor analysis identified 6 factors that potentially influenced satisfaction. After scale development, multiple regression analysis was used to test the research questions. It was found that the two genders displayed a difference in the factors influencing their satisfaction. For female students, only reputation (beta?=?.499, p?p?p?相似文献   
56.
马来西亚开放大学(OUM)90%以上的学生为在职人员。这些成年学生离开学校至少已经5年,而且大多数人的数学基础不好。因此,仅是在线学习加少量面授辅导的教学模式对他们来说还不能完全解决学习困难。学校试用了“课前指导工作室”与“补充指导”的教学方法,探讨了这一方法对学员的在线参与程度及考试结果的影响,运用源于探究团体模式的34项量表对在线论坛的内容进行了分析,结果表明,学员参加工作室与否同他们的期末考试成绩有很大关系。参加指导老师工作室及补充指导的学员与那些参加指导老师常规指导的学员相比,前者的在线参与程度及期末考试的平均分都存在着很大的差异。两组学员的数学探究团体模式平均分表明,两组学员在教学存在和认知存在方面有差异,但在社会存在方面基本相同。  相似文献   
57.
Hypomagnesaemia is common finding in current medical practice mainly in critically ill, post-operative patients and patients admitted to ICU in tertiary cancer cases. Magnesium has been directly implicated in hypokalemia, hypocalcaemia and dysrrthymias. We report a case of 60 year old patient, suffering from rectal carcinoma for a period of one year with confirmed hypokalemia, hypocalcaemia and hyponatremia. Magnesium supplementation corrected the underlying multiple electrolyte disturbances in the patient thus, establishing a positive correlation of magnesium with sodium, potassium and calcium.  相似文献   
58.
Pleural tuberculosis accounts for nearly 20% of Extra pulmonary tuberculosis. Adenosine deaminase, commonly used biomarker for the diagnosis, is non specific and there is paucity of literature on its correlation with conventional or newer methods for the diagnosis of extra pulmonary forms of TB. The aim of the study was to assess diagnostic potential of T cell function markers [interferon (IFN-γ), interleukin (IL-2) and IFN-γ/IL-2 ratio]; macrophage activation marker [neopterin]; and oxidative stress markers [protein carbonyl and malondialdehyde (MDA)] in pleural tuberculosis. 26 pleural TB cases diagnosed on the basis of suggestive chest X-ray and raised serum ADA levels and healthy controls were included in the study. Pleural fluid specimens were subjected to Zeihl Neelsen staining and culture on Lowenstein Jensen medium. Serum IFN-γ, IL-2, neopterin and protein carbonyl levels detection were done by ELISA and MDA levels were determined by measuring the thiobarbituric acid reactive substances. Median serum levels of IFN-γ, IL-2, IFN-γ/IL-2 ratio, neopterin, protein carbonyl and MDA were significantly different between cases and controls. Levels of all biomarkers except IL-2 were significantly higher in cases with contact history. Mean levels of ADA and ESR were 46.27 U/L and 46.62 mm/hr in PTB cases. AUC for IFN-γ, IL-2, IFN-γ/IL-2 ratio, neopterin, protein carbonyl and MDA were significantly discriminative for cases and controls. IFN-γ/IL-2 ratio was best discriminatory biomarker with highest area under ROC curve. Though no correlation was seen between ADA and any of the six biomarkers, ESR levels correlated significantly with all biomarkers except IL-2 by spearman’s correlation coefficient. Though all the circulating biomarkers under study provide useful supportive evidence for the diagnosis of PTB, further studies involving diverse control groups particularly non-PTB effusion are needed to validate these results.  相似文献   
59.
60.
This paper proposes a novel application of Nonlinear Proportional-Integral-Derivative (NPID) controller to effectively attain Maximum Power Point Tracking (MPPT) in Photovoltaic (PV) systems. The proposed controller is based on the basic structure of the PID controller wherein, its integral term gain is varied at run time according to instantaneous error. The performance of the NPID controller is assessed in terms of undershoot, settling time and ripple which have been evaluated under varying realistic irradiation and temperature profiles. The Teaching Learning Based Optimization (TLBO) tuned NPID controller is found to be superior to TLBO tuned PID, Perturb and Observe and Incremental Conductance classical MPPT methods for all the considered environmental profiles. Therefore, based on the presented comprehensive investigations, it is concluded that the proposed NPID controller is a promising MPPT technique.  相似文献   
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