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41.
Cost optimization continues to be a critical concern for many human resources departments. The key is to balance between costs and business value. In particular, computer science organizations prefer to hire people who are expert in only one skill area and have a slight superficial knowledge in other areas that gives them the ability to collaborate across different aspects of project. Community Question Answering networks provide good platforms for people and organizations to share knowledge and find experts. An important issue in expert finding is that an expert has to constantly update his knowledge after being saturated in his field of expertise to still be identified as expert. A person who fails to preserve his expertise is likely to lose his expertise. This work justifies this question that does take the concept of time into account improve the quality of expertise retrieval. We propose a new method for T-shaped expert finding that is based on temporal expert profiling. The proposed method takes the temporal property of expertise into account to mine the shape of expertise for each candidate expert based on his profile. To this end, for each candidate expert, we take snapshots of his expertise trees at regular time intervals and learn the relation between temporal changes in different expertise trees and candidates’ profile. Finally, we use a filtering technique that is applied on top of the profiling method, to find shape of expertise for candidate experts. Experimental results on a large test collection show the superiority of the proposed method in terms of quality of results in comparison with state-of-the-art.  相似文献   
42.
1IntroductionThePadéapproximationisatypeofrationalfractionapproximationtoafunction.Letfberepresentedbyapowerseriesf(x)=∑∞i=0c...  相似文献   
43.
The aim of this study was to examine the associations between learning support, student engagement and academic achievement among adolescents. We also examined the extent to which affective, behavioural and cognitive engagement play a mediating role in students’ perceived learning support from parents, teachers and peers, and contribute to their academic achievement. Malaysian adolescents (aged 12–17 years, N = 2359) completed a self-administered questionnaire based on an adapted version of the Student Engagement And Learning Support Scale. Item and factor analyses were performed to ensure appropriate psychometric properties of the scales. Pearson correlation analysis identified the relationship between variables and structural equation modelling was conducted to identify the role of student engagement as a mediator between learning support and academic achievement. The study provides empirical support for the hypothesis that perceptions of learning support influence adolescents’ affective, behavioural and cognitive engagement in school in different ways, which in turn influences their academic achievement. Cognitive engagement seemed to be the best predictor of academic achievement and the strongest mediator for all three types of learning support. Behavioural engagement was negatively associated with academic achievement, and affective engagement did not have a direct relationship with academic achievement, although it contributed indirectly through cognitive and behavioural engagement. The results of this study provide a basis for policy makers to initiate prevention and intervention programs for increasing the quality of parent–child, teacher–student and peer–peer relationships which ultimately could lead to improved academic competence and outcomes.  相似文献   
44.
Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude.  相似文献   
45.
Good quality deoxyribonucleic acid (DNA) is the pre-requisite for its downstream applications. The presence of high concentrations of polysaccharides, polyphenols, proteins, and other secondary me- tabolites in mango leaves poses problem in getting good quality DNA fit for polymerase chain reaction (PCR) applications. The problem is exacerbated when DNA is extracted from mature mango leaves. A reliable and modified protocol based on the cetyl- trimethylammonium bromide (CTAB) method for DNA extraction from mature mango leaves is described here. High concentrations of inert salt were used to remove polysaccharides; Polyvinylpyrrolidone (PVP) and β-mercaptoethanol were employed to manage phenolic compounds. Extended chloroform-isoamyl alcohol treatment followed by RNase treatment yielded 950?1050 μg of good quality DNA, free of protein and RNA. The problems of DNA degradation,contamination, and low yield due to irreversible binding of phenolic compounds and coprecipitation of polysaccharides with DNA were avoided by this method. The DNA isolated by the modified method showed good PCR amplification using simple se- quence repeat (SSR) primers. This modified protocol can also be used to extract DNA from other woody plants having similar problems.  相似文献   
46.
试析维吾尔族人生礼仪的文化内涵   总被引:1,自引:0,他引:1  
对维吾尔族人生礼仪作简要的介绍,进而分析其中所体现出的维吾尔人的社会伦理观、吉祥数崇拜观、生死观念,以及贯穿于各人生礼仪之中的人际馈赠关系。  相似文献   
47.
A short 33-item form of the Career Development Inventory was validated on a sample of 310 Iranian high school students. Factor analysis indicated that attitude and cognitive subscale items loaded on their respective factors, and that internal reliability coefficients at all levels were satisfactory to good. Support for validity was demonstrated by associations in the expected direction for career decidedness and career decision-making self-efficacy. This short form of the inventory shows promise as a measure of career maturity with students from a non-Western country.  相似文献   
48.
Date pits for feed preparation or oil extraction are soaked in water to soften before milling or extrusion. Knowledge of water absorption by the date pits helps in better managing the soaking duration. In this research, the process of water absorption by date pits was modeled and analyzed using Fick's second law of diffusion, finite element approach, and Peleg model. The moisture content of the pits reached to its saturation level of 41.5% (wet basis) after 10 d. The estimated coefficient of diffusion was 9.89×10-12 m2/s. The finite element model with a proposed ellipsoid geometry for a single date pit and the analytical model fitted better to the experimental data with R2 of 0.98. The former model slightly overestimated the moisture content of the pits during the initial stages of the soaking and the latter model generally underestimated this variable through the entire stages of soaking process.  相似文献   
49.
In this work, we demonstrate an integrated, single-layer, miniature flow cytometry device that is capable of multi-parametric particle analysis. The device integrates both particle focusing and detection components on-chip, including a “microfluidic drifting” based three-dimensional (3D) hydrodynamic focusing component and a series of optical fibers integrated into the microfluidic architecture to facilitate on-chip detection. With this design, multiple optical signals (i.e., forward scatter, side scatter, and fluorescence) from individual particles can be simultaneously detected. Experimental results indicate that the performance of our flow cytometry chip is comparable to its bulky, expensive desktop counterpart. The integration of on-chip 3D particle focusing with on-chip multi-parametric optical detection in a single-layer, mass-producible microfluidic device presents a major step towards low-cost flow cytometry chips for point-of-care clinical diagnostics.  相似文献   
50.
This study aimed at examining Jordanian pre-service special education teachers’ professionalism and preparation on the topic of child sexual abuse (CSA). Qualitative research data from interviews with 20 pre-service special education teachers were analysed using thematic analysis. The results showed that these participants generally hold avoiding behaviour toward speaking about CSA as it is an unspoken taboo. Participants also hold low levels of professionalism on the topic of CSA. The results also demonstrate that they felt that their preparation programme is inadequate and desired more content and pedagogy courses that relate to CSA. Implications and recommendations are presented in light of the study findings.  相似文献   
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