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Competency-based approaches using information and communication technologies have been the main solution of the organization’s expectations in all fields (public and private) to increase the products’ quality and employees’ capacity. Furthermore, the concept of competency can have several different definitions, which may make it difficult to model. As a result, without a good representation of the knowledge and competency and reusable definitions of competence, an e- Learning system will be unable to adapt to its users, to personalize learning activities. In this paper, we present a view of some important competency definitions and the main competency specifications, like the HR-XML specification (Human Resources XML), and the IMS Reusable Definition of Competency or Educational Objective (IMS RDCEO). Moreover, we suggest a competency model for training and education based on these specifications. 相似文献
23.
Izatus Shima Taib Siti Balkis Budin Seri Maseran Siti Nor Ain Jamaludin Mohamed Santhana Raj Louis Srijit Das Sulaiman Sallehudin Nor Fadilah Rajab Othman Hidayatulfathi 《Journal of Zhejiang University. Science. B》2009,10(11):813-819
Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, che-mopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinoeyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage. 相似文献
24.
Mohammed A. El-Magd Ayman A. Saleh Abeer A. Nafeaa Shymaa M. El-Komy Mohamed A. Afifi 《Journal of Zhejiang University. Science. B》2017,18(12):1064-1074
The insulin-like growth factor 1 (IGF1) gene is a member of the group of somatotropin axis genes that play a significant role in cell proliferation and growth of muscles. Here, we searched for polymorphisms in buffalo IGF1 and found two novel single nucleotide polymorphisms (SNPs), G64A and G280A, in the noncoding sequences of exon 1 and exon 4, respectively. Statistical analysis of different genotypes showed that the individuals with GG genotypes had significantly (P<0.05) higher body weight (BW) and average daily gain (ADG) than those with other genotypes at ages of 3–6 months in G64A SNP and 6–9 months in G280A SNP. The combined genotypes of these two SNPs produced three haplotypes, GG/GG, AG/AG, and AA/AA, which were significantly associated (P<0.0001) with BW and ADG at an age from 3 to 12 months. Buffaloes with the homozygous GG/GG haplotype showed higher growth performance than other buffaloes. The two SNPs were correlated with mRNA levels of IGF1 and IGF1 receptor (IGF1R) in semitendinosus muscle as well as with the serum concentration level of IGF1. Also, buffaloes with GG/GG haplotype showed higher mRNA and serum concentration levels. The data revealed that these two SNPs could be valuable genetic markers for selection of Egyptian buffaloes for better performance in the population. 相似文献
25.
Mohamed Ibrahim Carmen M. Greenwood Denna Wheeler 《Learning, Media and Technology》2012,37(3):220-235
Informed by the cognitive theory of multimedia learning, this study examined the effects of three multimedia design principles on undergraduate students' learning outcomes and perceived learning difficulty in the context of learning entomology from an educational video. These principles included segmenting the video into smaller units, signalling to direct students' attention to relevant information, and weeding to remove any non-essential content (SSW). It was hypothesized that the SSW treatment would decrease perceived learning difficulty and facilitate the transfer of knowledge and the structural knowledge acquisition. Results of the study demonstrate that participants in the SSW group outperformed the non-SSW group on the tests of knowledge transfer and structural knowledge acquisition and reported lower levels of learning difficulty. These findings support the use of SSW to help novice learners organize and integrate knowledge from complex, dynamic audio-visual media like video. 相似文献
26.
Mohamed Taher Amin Ahmed Khan Muhammed Burhanuddin 《International Information and Library Review》2013,45(4):337-345
This paper relates to the difficulty in retrieving precise information from big repositories of magazine articles in full text, and proposes an Extended Markup Language (XML) vocabulary for improving retrieval rates. The hypothesis tested was as follows: Magazine articles marked up with an XML vocabulary, indexed only by selected parts, give more precise search results than the same search using full text index.The study was exploratory with the following characteristics: 29 magazine articles were tested for results, 8 scholars were interviewed for defining 23 search strategies and evaluating results. The data showed that precision improved from 40.72% with full text search to 62.84% using XML markup and searching only in specific labels.Revision of the vocabulary and more testing has to be done by the library and information science community in order to obtain a valid vocabulary and provide more research results. Cultural characteristics and politics of librarians and information managers’ community are as important as technical issues in order to consider any technical proposal to be implemented successfully to achieve interoperability. 相似文献
27.
Mohamed El-Shahat Ebeid Kadry Abdel-Kader El-Bakry 《Indian journal of clinical biochemistry : IJCB》2009,24(3):234-240
The present study aimed to estimate the cellular immune response to infection by different HCV genotypes in some Egyptian
patients with chronic liver disease. HCV-RNA and HCV genotypes were conducted using type-specific primers to amplify the core
region of HCV genome. The levels of IFN-gamma and TNF-alpha, PIIINP, SOD enzyme were also determined. The results showed that
genotype 4 was the prevalent one (88.57%).Genotype 3 was found mixed with genotype 2 and 4 (11.42% and 34.28% respectively).
Genotype 1 was absent from patients under study. No significant differences were observed in the level of IFN-gamma interferon,
SOD enzyme and ALT enzyme between those genotypes. On the other hand the level of TNF-alpha was greatly increased in patients
infected with mixed HCV genotypes 3, 4 compared with patients with genotype 4 and those infected with mixed genotypes 2, 3.
Otherwise PIIINP was decreased significantly of the same group compared with other groups. 相似文献
28.
The aim of this paper is to provide a comparative analysis of higher education and the graduate labour markets in selected European countries (France, Germany, Spain and United Kingdom) in the context of the expectations of graduates and prospective employers, and respective recruitment and selection practices. Expectations of graduating students from a number of European collaborating universities are sought and analysed in order to find out about a match between the knowledge and skills of graduates and the needs of European employers. The study examines the process of graduate recruitment, employee and employer expectations, and the role of higher education institutions in meeting such expectations. Primary data was gathered from 252 employers and 485 final year (graduating) students through the use of questionnaires. The analysis of the data collected has revealed different approaches to but similar methods of graduate recruitment between the four countries. Despite the current differences in higher education systems and labour market trends, the expectations of employers and graduating students are more similar than different. It is concluded that EU graduates will have good employment prospects in an integrated labour market. 相似文献
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30.
In this paper, a novel approach for the design of an indirect adaptive fuzzy output tracking excitation control of power system generators is proposed. The method is developed based on the concept of differentially flat systems through which the nonlinear system can be written in canonical form. The flatness-based adaptive fuzzy control methodology is used to design the excitation control signal of a single machine power system in order to track a reference trajectory for the generator angle. The considered power system can be written in the canonical form and the resulting excitation control signal is shown to be nonlinear. In case of unknown power system parameters due to abnormalities, the nonlinear functions appearing in the control signal are approximated using adaptive fuzzy systems. Simulation results show that the proposed controller can enhance the transient stability of the power system under a three-phase to ground fault occurring near the generator terminals. 相似文献