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101.
The article discusses the need for initiatives to be undertaken by the King Fahd University of Petroleum & Minerals Library administration to acquire archives of and perpetual access to its subscribed electronic journals. It also reports the findings of a survey conducted to ascertain the publishers' positions on archiving services and the right to permanently access licensed materials paid for during the period of a license agreement. The findings are expected to help the library to plan for securing the right over a three-year period to ongoing access to the back files of journals from fifteen commercial and society publisher platforms. 相似文献
102.
This study examined the use of electronic resources among academic scholars of The Islamia University of Bahawalpur (IUB), Punjab, Pakistan. A quantitative survey was found most convenient and useful for this study. The total population of the study was 169 research students in IUB. The response rate was 79% and 133 utilizable responses were coded and analyzed by using SPSS software. Results of the study showed that most of the researchers (61%) used electronic resources daily for many purposes and reasons. Most of them (57%) were “satisfied” with the usage of electronic resources. Learning, education, and research were the main purposes, and easy use and easy access to documents were the major reasons of using these resources. Lack of internet connection is the major problem faced by the respondents. 相似文献
103.
Nadeem Akhtar Abbasi Tariq Pervaiz Ishfaq Ahmed Hafiz Mehwish Yaseen Azhar Hussain 《Journal of Zhejiang University. Science. B》2013,14(9):774-784
In vitro cultures of loquat cultivar Mardan were established using shoot apices after treating with NaOCl (5%, 7%, 10%, 12%, 14% (v/v)) for 12 min and HgCl2 (0.01%, 0.05%, 0.10%, 0.20%, 0.25% (w/v)) for 2 min. A maximum survival rate of 70% was recorded after surface sterilization with 10% NaOCl. Caulogenic response was assessed on Murashige and Skoog (MS) medium fortified with assorted combinations of the cytokinins, benzylaminopurine (BAP), kinetin, and N6-(2-isopentyl)adenine (2iP). Treatment of BAP 1.5 mg/L combined with 2iP 9.0 mg/L and kinetin 1.5 mg/L was found to be optimum for shoot morphogenesis in terms of the number and subsequent growth of shoots, while the highest shoot length was yielded by the combination of BAP 0.5 mg/L, kinetin 0.5 mg/L, and 2iP 3 mg/L. Higher levels of cytokinins induced callogenesis, vitrification and stunted growth to some extent. For rhizogenesis, uniform sized micro-shoots were excised and transferred to half-strength MS medium containing auxins. The best rooting expression was observed with naphthaleneacetic acid (NAA) 1 mg/L combined with indole-3-butyric acid (IBA) 2 mg/L and paclobutrazol (PBZ) 1 mg/L. 相似文献
104.
Citizens as consumers: Profiling e-government services’ users in Egypt via data mining techniques 总被引:1,自引:0,他引:1
This study uses data mining techniques to examine the effect of various demographic, cognitive and psychographic factors on Egyptian citizens’ use of e-government services. Data mining uses a broad family of computationally intensive methods that include decision trees, neural networks, rule induction, machine learning and graphic visualization. Three artificial neural network models (multi-layer perceptron neural network [MLP], probabilistic neural network [PNN] and self-organizing maps neural network [SOM]) and three machine learning techniques (classification and regression trees [CART], multivariate adaptive regression splines [MARS], and support vector machines [SVM]) are compared to a standard statistical method (linear discriminant analysis [LDA]). The variable sets considered are sex, age, educational level, e-government services perceived usefulness, ease of use, compatibility, subjective norms, trust, civic mindedness, and attitudes. The study shows how it is possible to identify various dimensions of e-government services usage behavior by uncovering complex patterns in the dataset, and also shows the classification abilities of data mining techniques. 相似文献
105.
Abdul Samad Aziz Madhav Govind Kalekar Adinath Narayan Suryakar Tabita Benjamin Milsee Jaya Prakashan Bijle Mohammed Nadeem Ahmed Mehmood Sayyad 《Indian journal of clinical biochemistry : IJCB》2013,28(4):374-380
The present study aims to assess and compare the biochemical oxidative stress markers in male smokers and non-smokers with chronic periodontitis. One hundred thirty-four male chronic periodontitis patients and 64 apparently healthy male volunteers were recruited for the study. The periodontal status was evaluated by measuring gingival index, plaque index, papillary bleeding index and clinical attachment loss using UNC-15 probe. The biochemical markers estimated were total antioxidant capacity, RBC-superoxide dismutase, glutathione peroxidase, vitamin C, malondialdehyde and C-reactive protein. The obtained results indicate higher oxidative stress in chronic periodontitis. Smokers with chronic periodontitis show significantly higher periodontal clinical parameters and relatively higher systemic oxidative stress. Vitamin C estimation may be an important biochemical parameter in conjunction with clinical parameters for diagnosis of chronic periodontitis in smokers. 相似文献
106.
Saleh A. Al-Abood Keith Davids Simon J. Bennett Derek Ashford Manuel Martinez Marin 《Journal of sports sciences》2013,31(7):507-520
In the visual perception perspective of observational learning, the manipulation of relative and absolute motion information in visual demonstrations optimally directs learners’ search towards appropriate task solutions. We assessed the effect of emphasizing transformational information and removal of structural information using point-light kinematic displays in approximating the model’s relative motion patterns. Participants viewed computer-simulated point-light demonstrations or normal video demonstrations before and intermittently throughout 100 acquisition trials with knowledge of results on an underarm modified-dart aiming task. On the next day, all participants performed 20 retention trials without demonstrations. The kinematics of spatial and temporal coordination and control variables were examined relative to the model’s action, as well as performance scores. The results indicated that approximation of the model’s spatial and temporal coordination and control patterns was achieved after observation of either type of demonstrations. No differences were found in movement outcomes. In a second experiment, the effects of manipulating absolute motion information by slowmotion demonstrations were examined relative to real-time demonstrations. Real-time demonstrations led to a closer approximation to the model’s spatial and temporal coordination patterns and better outcome scores, contradicting predictions that slow-motion displays convey intact relative motion information. We speculate that the effect of visual demonstration speed on action perception and reproduction is a function of task constraints ‐ that is, novelty or familiarity of relative motion of demonstrated activities. 相似文献
107.
This multiple case study examined pre-service teachers perceptions of effective post-secondary instruction. Pre-service teachers
were asked to write essays describing an effective teacher of their choice. Twenty-one essays were randomly selected. Data
analysis involved open coding of each essay, content analysis of each essay using Anderson and Burns’ (Research in classrooms:
The study of teachers, teaching, and instruction (1st ed.). Oxford, England; New York: Pergamon Press, 1989) empirically derived
dimensions of instruction, and effect size analysis of student and teacher roles. Instructional components were identified
that differentiate between effective inquiry instruction and effective instruction. Effective inquiry instruction was associated
with more and different teacher and student roles, more activities as part of instruction, and more student small group discussion
than was effective instruction. 相似文献
108.
Sameen Ahmed Khan 《Resonance》2012,17(5):468-475
It is straightforward to construct the set of equivalent resistance for circuits constructed from a bunch of four or five equal resistors. But as the bunch size increases it becomes difficult to find the order of the set of equivalent resistances. Even the computer programs runs out of memory. Here we present an analytical result using simple mathematical machinery. The size of the set is shown to be less than 2.618 n . 相似文献
109.
Jamy Stillman Kathryn Struthers Ahmed Erika Castañeda-Flores 《The Educational forum》2013,77(4):432-452
In this article, we share findings from a 3-year project in which novice teacher educators participated in Freirean culture circles and Boalian Theatre of the Oppressed (teatro) in order to critically explore the work of justice-oriented teacher education. Anchored in one of the project’s most resonant scenarios, the article illustrates how teatro cultivated among participants courage to confront injustice, while also shedding light on the complexities teacher educators may face when attempting to facilitate teacher learning, particularly when such learning is centered on equity and justice. 相似文献
110.
The major aim of power quality (PQ) enhancing techniques is to maintain a specified voltage magnitude at a desired frequency for sensitive loads irrespective of faults on the power distribution network. The dynamic voltage restorer (DVR) is a device used to mitigate voltage sags to regulate load voltage. This paper presents a mathematical model for leading series voltage injection to mitigate sags thereby achieving the improvement of the utility power factor as well as power sharing between the DVR and utility. The power sharing will be as per requirement to compensate the sags considering the available distributed generation (DG). The approach of mitigating voltage sags using the concept of leading series voltage injection is suitable for those locations where phase shift in the voltage will not cause any problem. The MATLAB/SIMULINK SimPowerSystem toolbox has been used to obtain simulation results to verify the proposed mathematical model. 相似文献