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51.
Taxonomy of e-readiness assessment measures   总被引:1,自引:0,他引:1  
To benefit from the advantages of information society, on the one hand, and to be afraid of being left further behind by Global Society and the increase in the digital divide, on the other hand, stimulate countries to be part of Global Information Society. These issues have led policymakers to move towards such a society by identifying the objectives, goals and targets. Planning to achieve these objectives needs a real understanding of the current situation, which is obtained by e-readiness assessment measures. There has been a proliferation of e-readiness assessment measures in recent years that each one has a certain objective. This paper elaborates on and categorizes these measures that help scholars and policymakers to (1) select the measures that fit in with their objectives, (2) prevent the repetitive research, (3) identify the defects and flaws of previous measures and correct them in their own measures, and (4) use the experiences of previous measures to construct their own ones. Based on definitions, objectives, dimensions, methods and approaches, in this paper, the measures are categorized and finally, a measure for e-readiness assessment is presented. Since this measure is a convergence of e-readiness assessment measures, the experienced modelers have consensus on it and it is more suitable to measure e-readiness of countries. Also, it can be exploited as the basis and standard for internationally comparable information society statistics.  相似文献   
52.
A fast and efficient page ranking mechanism for web crawling and retrieval remains as a challenging issue. Recently, several link based ranking algorithms like PageRank, HITS and OPIC have been proposed. In this paper, we propose a novel recursive method based on reinforcement learning which considers distance between pages as punishment, called “DistanceRank” to compute ranks of web pages. The distance is defined as the number of “average clicks” between two pages. The objective is to minimize punishment or distance so that a page with less distance to have a higher rank. Experimental results indicate that DistanceRank outperforms other ranking algorithms in page ranking and crawling scheduling. Furthermore, the complexity of DistanceRank is low. We have used University of California at Berkeley’s web for our experiments.  相似文献   
53.
Free iron in serum has been found in several disease conditions including diabetes. In the present work, we studied the relationship between free iron, fasting blood glucose (FBG) and glycated haemoglobin (HbA1c). Study was carried out on 50 type 2 diabetes cases under poor glycemic control associated with complications, 53 type 2 diabetes cases under good glycemic control and 40 healthy controls. We estimated free iron, both ferrous (Fe+2) and ferric (Fe+3) form, protein thiols, lipid hydroperoxides, FBG, HbA1c and serum ferritin levels in serum. There was a significant increase in free iron in Fe+3 state (p <0.01), HbA1c (p<0.01), serum ferritin (p<0.01), lipid hydroperoxides (p<0.01) and significant decrease in protein thiols (<0.01) in diabetes cases under poor glycemic control compared to diabetes cases under good glycemic control and healthy controls. Free iron correlated positively with HbA1c (p<0.01). Poor glycemic control and increase in glycation of haemoglobin is contributing to the increase in free iron pool which is known to increase oxidant generation.  相似文献   
54.
Niaz  Mansoor 《Science & Education》2000,9(3):279-287
The main objective of this study is to establish a relationship between students' understanding of gases and its parallels in the history of science (rational reconstruction). Fifty-nine freshman students were asked to respond to a gas problem that did not require any calculations but rather conceptual understanding (due to molecular collisions, gases occupy all the available space). Before responding to the problem students were exposed to an elementary version of the kinetic theory of gases. Results obtained showed that a large proportion of the students gave explanations that approximate quite closely to an idealized form of the Lattice Theory of Gases. This theory considered molecules in gases to be arranged in the form of regular lattices, rather as if gases were highly expanded solids, and was held by most chemists until about 1860. It is concluded that some of the students' alternative conceptions about gas behavior (attractive forces between gas molecules increase as the temperature decreases) are resistant to change and recapitulate theories scientists held in the past.  相似文献   
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56.
In today's changing world, the idea of internationalization of higher education especially in developing countries has been deduced from globalization of education process. The international aspect of higher education is becoming increasingly important, composite, and confusing. The higher education has an effect on the society through policy-making, funding, and planning. The purpose of this paper is to analyze the meaning, definition, importance, necessity, and pre-requisites of internationalization of higher education. This paper also studies the programs and strategies of internationalization of higher education. Key challenges for the future direction of internationalization are identified in this paper.  相似文献   
57.
This paper describes the fabrication of a waveguide and the analysis of its polarization characteristics by applying light-emitting diode (LED) pumping lights to its surface. By using double tubed coaxial line (DTCL) microwave plasma chemical vapor deposition (MPCVD) equipment, an a-Si:H/SiN multilayer waveguide was fabricated whose thickness could be controlled at nanometer order. The main structural material of the waveguide sample consisted of a combination of layers of amorphous silicon hydrogen and silicon nitrate. Once the sample was ready, another major objective of the experiment was to analyze the polarization characteristics of the fabricated waveguide. The idea of the experiment was to analyze how the waveguide reacts when three types of LED (blue, yellow, and red) are radiated onto its surface. The results showed that the fabrication of the a-Si:H/SiN sample is successful. Most effective transmission results, which accord with the polarization characteristics analysis, were obtained.  相似文献   
58.
This study used a sequential set-up to investigate the consecutive effects of timing of supportive information presentation (information before vs. information during the learning task clusters) in interactive digital learning materials (IDLMs) and type of collaboration (personal discussion vs. online discussion) in computer-supported collaborative learning (CSCL) on student knowledge construction. Students (N = 87) were first randomly assigned to the two information presentation conditions to work individually on a case-based assignment in IDLM. Students who received information during learning task clusters tended to show better results on knowledge construction than those who received information only before each cluster. The students within the two separate information presentation conditions were then randomly assigned to pairs to discuss the outcomes of their assignments under either the personal discussion or online discussion condition in CSCL. When supportive information had been presented before each learning task cluster, online discussion led to better results than personal discussion. When supportive information had been presented during the learning task clusters, however, the online and personal discussion conditions had no differential effect on knowledge construction. Online discussion in CSCL appeared to compensate for suboptimal timing of presentation of supportive information before the learning task clusters in IDLM.  相似文献   
59.
The majority of today's students in online higher education are millennials and have grown up using technology. Therefore, there is a need to determine if their expectations from online learning are different from previous contextual studies and whether or not these vary across gender. This study used a mixed method approach, using focus groups, followed by online surveys of 834 undergraduate students from the University of Mauritius enrolled in an online course. Using factor analysis and structural equation modelling, the study found no significant differences based on gender for millennials, but identified three significant antecedents of student satisfaction for both males and females: university reputation; physical facilities; and instructor empathy.  相似文献   
60.
Cardiovascular diseases (CVD) are recognized as major mortality causes and imposes tremendously heavy socio-economic burden worldwide. A vast variety of risk factors have been introduced in the literature known to enhance the incidence of CVD, such as hyperlipidemia. Therefore in order to make an accurate clinical decision it is essential to have appropriate reference ranges for lipids and lipoprotein particles in a particular population. Healthy female (n = 601) and male (n = 617) cases were randomly selected according to certain exclusion criteria from individuals visiting the major University hospital clinics situated in different part of Ahvaz city, Iran, from June 2010 to December 2010. Fasting blood samples (10 ml) were collected and analyzed for total cholesterol, total triglyceride and HDL-C employing enzymatic assays of CHOD-PAP, GPO-PAP and homogenous methods respectively. The samples were obtained such to include the ethnic populations of Persian, Arab. Lore leaving in this city. The data were analyzed statistically by SPSS-18 software. The obtained results were analyzed then age ethnic-wise and reference ranges (mean ± 1SD) were calculated. Remarkable differences between the obtained results for our population with other nations were seen. Also ethnic difference for HDL-C among our cases was noted. The observed significant differences among different nations and ethnicities emphasizes the need for nation-specific, local reference ranges for lipids and lipoproteins particles, to be established.  相似文献   
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