排序方式: 共有80条查询结果,搜索用时 294 毫秒
41.
42.
Ismail Sengor Altingovde Özlem Nurcan Subakan Özgür Ulusoy 《Information processing & management》2013
In-memory nearest neighbor computation is a typical collaborative filtering approach for high recommendation accuracy. However, this approach is not scalable given the huge number of customers and items in typical commercial applications. Cluster-based collaborative filtering techniques can be a remedy for the efficiency problem, but they usually provide relatively lower accuracy figures, since they may become over-generalized and produce less-personalized recommendations. Our research explores an individualistic strategy which initially clusters the users and then exploits the members within clusters, but not just the cluster representatives, during the recommendation generation stage. We provide an efficient implementation of this strategy by adapting a specifically tailored cluster-skipping inverted index structure. Experimental results reveal that the individualistic strategy with the cluster-skipping index is a good compromise that yields high accuracy and reasonable scalability figures. 相似文献
43.
本研究的目的在于构建一个电子环境中的可信任文件管理框架.通过文献研究和最佳实践,对可信任电子文件管理的有关标准进行整理,并将这些标准进行专家测试,建立了构建电子文件可信任管理所需的因素,即监管、文件保管系统、档案、技术、人员技能和素质.这个框架为良好的文件管理实践奠定了基础. 相似文献
44.
45.
Objectives
The Convention on the Rights of the Child (CRC) was ratified by Saudi Arabia 15 years ago; yet addressing the issue of child maltreatment only began in more recent years. School professionals play a significant role in children's lives, as they spend a great deal of time with them and are hence essential to protecting and identifying those in danger or at risk. The objective of this study is to identify school professional's awareness of child maltreatment and the existing national policies and procedures to examine the extent of efforts made in Saudi Arabia and to activate the roles of schools and school professionals in protecting children from violence and implementation of Article 19 of the CRC.Methods
This was a cross-sectional study, where school professionals from randomly selected schools throughout the country were invited to participate in a self-administered questionnaire.Results
A total of 3,777 school professionals participated in the study. Fifty-five percent of professionals had at least 10 years of work experience. A low-level of awareness of child maltreatment was found in about 1/3 of school professionals. Only 1.9% of school professionals had ever attended any sort of specific training on child maltreatment, though 69.3% of those who had not, were willing to attend future training. With regards to awareness of CRC Article 19 or policies and procedures addressing child maltreatment, only 22% reported being aware of it.Conclusion
The majority of school professionals in Saudi Arabia have a low-intermediate level of awareness of child maltreatment, ratification of CRC, and related national policies and procedures, yet most are willing to attend training programs on this subject matter. Efforts need to be made in the country to fill this gap. 相似文献46.
47.
The paper deals with the optimal control of a distributed host structure consisting of two elastically connected complex continuous double-string system and subjected to certain excitation load. Investigation of the behavior of such system is of great theoretical and practical importance. A technique is proposed to actively damp out the undesired vibrations in the structures by a combination of applied actuators and displacement feedback gains. Two performance measures, involving energies at the terminal time as well as applied and feedback control efforts, are introduced. The optimality conditions of the applied actuators are derived by using the method of eigenfunction expansion and calculus of variations. The feedback parameters are numerically determined from the solution of a minimization problem. The proposed approach is illustrated by a numerical example involving a system which consists of two strings subjected to a continuous load. 相似文献
48.
Zhi Chao Ong Hong Cheet Lim Shin Yee Khoo Zubaidah Ismail Keen Kuan Kong Abdul Ghaffar Abdul Rahman 《浙江大学学报(A卷英文版)》2017,18(2):92-105
The impact-synchronous modal analysis (ISMA), which uses impact-synchronous time averaging (ISTA), allows modal testing to be performed during operation. ISTA is effective in filtering out the non-synchronous cyclic load component, its harmonics, and noises. However, it was found that at operating speeds that coincide with the natural modes, ISMA would require a high number of impacts to determine the dynamic characteristics of the system. This finding has subsequently reduced the effectiveness and practicality of ISMA. Preservation of signatures during ISTA depends on the consistency of their phase angles on every time block but not necessarily on their frequencies. Thus, the effect of phase angles with respect to impact is seen to be a very important parameter when performing ISMA on structures with dominant periodic responses due to cyclic load and ambient excitation. The responses from unaccounted forces that contain even the same frequency as that contained in the response due to impact are diminished with the least number of impacts when the phase of the periodic responses is not consistent with the impact signature for every impact applied. The assessment showed that a small number of averages are sufficient to eliminate the non-synchronous components with 98.48% improvement on simulation and 95.22% improvement on experimental modal testing when the phase angles with respect to impact are not consistent for every impact applied. 相似文献
49.
Rajes Qvist Ikram Shah Ismail Karuthan Chinna Sekaran Muniandy 《Indian journal of clinical biochemistry : IJCB》2008,23(3):246-249
Although HbA1C is widely accepted as a useful index of mean blood glucose in type 2 diabetic patients its usefulness as screening test for
diabetes has been controversial. The present study was undertaken to determine whether the level of HbA1C predicted diabetes in a prediabetic group of subjects. Plasma lipids, oral glucose tolerance, HbA1C was determined in 90 normal control subjects, 57 offspring of one type 2 diabetes mellitus parent and 11 diagnosed type 2
diabetes mellitus individuals. The mean age of participants was 44.5 yrs (not significantly different amongst the three groups)
and the mean body mass index was 26.8 (not significantly different amongst the three groups). Two hours after a 75 g glucose
challenge, the offspring had a significantly higher plasma glucose level (mean = 7.1 mmol/L, p value = 0.002) than the normals. Similarly the HbA1C values were higher in the offspring than in the normals (mean = 5.78%, p value = 0.016). Besides the significantly higher values for oral glucose tolerance test and HbA1C, the diabetics also were significantly higher for triglycerides (mean = 2.25mmol/L), total cholesterol (mean = 6.24mmol/L)
and systolic blood pressure (mean = 138.45mm Hg) than the offspring (P value = 0.031, 0.006, 0.010) and the normals (P value = 0.026, 0.018, 0.002) respectively. The mean values of diastolic blood pressure, LDL cholesterol and HDL cholesterol
were not significantly different amongst the three groups. 相似文献
50.
To ensure the success of the e-learning initiatives, OUM has developed its own e-learning management system, known as myLMS. Since its introduction, many modifications and improvements have been introduced to increase its effectiveness. It is now timely that OUM take stock of its students' attitudes towards e-learning. Thus, a survey was conducted on about 1,000 students at one of OUM's own learning centres, that is, the Kelantan Regional Centrel. The study indicated that generally the teacher cohort had a somewhat neutral attitude towards e-learning. The use of e-learning was more specifically aimed at achieving short term goals of obtaining good coursework and examination grades by capitalizing on the use of the Discassion Board and Courseware. A closer examination reveals that the females prefer the Discussion Board while the males prefer the Courseware. Learners in the Engineering and English programmes had more positive attitudes towards e-learning compared to learners in the Mathematics and Science programmes. Learners with CGPA 〉 3.0 who are categorized as high achievers are more positive towards e-learning as compared to the low achievers ( CGPA 〈 3.0). Age difference, learners' income per month, learners' Internet and e-learning habits were also found to be predictors of attitude towards e-learning. 相似文献