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Kanwal Ameen S. Jalal Haider 《Library Collections, Acquisitions, and Technical Services》2007,31(3-4):208-219
University libraries in Pakistan spend a large portion of their funds on buying books and these are still the most important part of libraries' collections. Selection policies and practices play fundamental role in developing a strong book collection. This study aims to explore the policies, methods and procedures of selecting books in the university libraries of Pakistan. Data for the study were collected following multi-method approach, through questionnaires and unstructured interviews with the university librarians and faculty members for the doctoral research by the present author during 2003 to 2004. The analysis of data shows that the factors affecting successful execution of the practice of effective selection include: overly dependence on the faculty for selection, constraints of faculty members as selectors, non-availability of selection aids, lack of awareness regarding online resources available for selection, etc. The study suggests some feasible ways to improve the situation. The findings and suggestions may be of value to the countries with similar situations in the developing world. 相似文献
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Mohammad Sadegh Cheri Hamidreza Shahraki Jalal Sadeghi Mohammadreza Salehi Moghaddam Hamid Latifi 《Biomicrofluidics》2014,8(5)
Measurement and control of pressure-driven flow (PDF) has a great potential to enhance the performance of chemical and biological experiments in Lab on a Chip technology. In this paper, we present an optofluidic flow sensor for real-time measurement and control of PDF. The optofluidic flow sensor consists of an on-chip micro Venturi and two optical Fabry-Pérot (FP) interferometers. Flow rate was measured from the fringe shift of FP interferometers resulted from movement fluid in the on-chip micro Venturi. The experimental results show that the optofluidic flow sensor has a minimum detectable flow change of 5 nl/min that is suitable for real time monitoring and control of fluids in many chemical and biological experiments. A Finite Element Method is used to solve the three dimensional (3D) Navier–Stokes and continuity equations to validate the experimental results. 相似文献
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Statistical theories of goodness-of-fit tests in structural equation modeling are based on asymptotic distributions of test statistics. When the model includes a large number of variables or the population is not from a multivariate normal distribution, the asymptotic distributions do not approximate the distribution of the test statistics very well at small sample sizes. A variety of methods have been developed to improve the accuracy of hypothesis testing at small sample sizes. However, all these methods have their limitations, specially for nonnormal distributed data. We propose a Monte Carlo test that is able to control Type I error with more accuracy compared to existing approaches in both normal and nonnormally distributed data at small sample sizes. Extensive simulation studies show that the suggested Monte Carlo test has a more accurate observed significance level as compared to other tests with a reasonable power to reject misspecified models. 相似文献
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Monotonic triaxial experiments to evaluate steady-state and liquefaction susceptibility of Babolsar sand 总被引：1，自引：0，他引：1
In this study, drained and undrained triaxial tests under isotropic and anisotropic consolidations were conducted on reconstituted samples of Babolsar sand, which underlies a densely populated, seismic region of the southern coast of the Caspian Sea, Mazandaran, Iran. It was demonstrated that the sand experienced all possible states of liquefiable soil： flow failure, limited flow, and dilation. The steady-state and flow liquefaction lines of this sand were presented and compared with previously tested sands. It is shown that the initial stress anisotropy can affect the potential of volume change and pore pressure generation. The steady-state line （SSL）, however, remains identical for the isotropically and anisotropically consolidated specimens under drained and undrained conditions. The tests data were then analyzed in order to investigate the liquefaction susceptibility of this sand in terms of parameters such as the state parameter, relative state parameter index, and lateral earth pressure ratio at failure. 相似文献
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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
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Abstract Cross‐border informal trade is one of the most important issues between India and Bangladesh. It takes place between people who live a short distance apart, but who find themselves separated by an international boundary. The people of international border areas believe that cross‐border informal trade is a process to maintain a sustainable livelihood because it provides a livelihood to the unemployed. This research has analysed the nature and impact of informal border trade between India and Bangladesh. It has highlighted the sources of security and insecurity through the process of informal border trade. It also analyses the different socio‐economic conditions of informal border trade in border trade prone areas. This research argues that although informal border trade is considered illegal, it is necessary for the maintenance of the livelihood for the poor in the bordering areas. The state failures in fulfilling the needs of the poor force them to involve themselves in informal border trade. 相似文献
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INTRODUCTIONTopologicalsolitonshavebeenthesubjectofmuchresearchforthepastseveraldecades.Theyarestaticsolutionstogeometricevolutionequationswithcertaintopologicalproperties.To pologicalsolitonsariseinavarietyofphysicalproblemssuchasdomainwallsandmagneticbu… 相似文献
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Jalal Ismaili El Houcine Ouazzani Ibrahimi 《Education and Information Technologies》2017,22(3):883-899
Assistive Technology (AT) revolutionized the process of learning for special needs students during the past three decades. Thanks to this technology, accessibility and educational inclusion became attainable more than any time in the history of special education. Meanwhile, assistive technology devices remain unreachable for a large number of students with disabilities, especially in under-developed and developing countries like Morocco due to a number of factors, especially, availability and affordability. Mobile learning, using smartphones and tablets in particular, may provide alternative solutions as special education tools in such countries. Additionally, open source platforms, particularly Google play store with all the applications it accommodates for disabled people, may obviate the need for monofunctional, sometimes expensive, AT devices. The present paper sets out to investigate potentials of using smartphones and tablets as alternative learning tools for assistive technology devices within formal and informal learning environments. It compares seven free Google Play medical apps with seven assistive technology devices at the level of functionality and affordability. The apps are of relevance to cases of physical as well as mental disabilities, namely hearing impairment, visual impairment, autism and speech articulation disorders. 相似文献
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Yevgen Borodin Valentin Polishchuk Jalal Mahmud I.V. Ramakrishnan Amanda Stent 《Information processing & management》2013
We present a Life-Long Learning from Mistakes (3LM) algorithm for document classification, which could be used in various scenarios such as spam filtering, blog classification, and web resource categorization. We extend the ideas of online clustering and batch-mode centroid-based classification to online learning with negative feedback. The 3LM is a competitive learning algorithm, which avoids over-smoothing, characteristic of the centroid-based classifiers, by using a different class representative, which we call clusterhead. The clusterheads competing for vector-space dominance are drawn toward misclassified documents, eventually bringing the model to a “balanced state” for a fixed distribution of documents. Subsequently, the clusterheads oscillate between the misclassified documents, heuristically minimizing the rate of misclassifications, an NP-complete problem. Further, the 3LM algorithm prevents over-fitting by “leashing” the clusterheads to their respective centroids. A clusterhead provably converges if its class can be separated by a hyper-plane from all other classes. Lifelong learning with fixed learning rate allows 3LM to adapt to possibly changing distribution of the data and continually learn and unlearn document classes. We report on our experiments, which demonstrate high accuracy of document classification on Reuters21578, OHSUMED, and TREC07p-spam datasets. The 3LM algorithm did not show over-fitting, while consistently outperforming centroid-based, Naïve Bayes, C4.5, AdaBoost, kNN, and SVM whose accuracy had been reported on the same three corpora. 相似文献