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91.
Knowledge is the currency of the current economy and a vital resource for sustaining organisational performance in today’s knowledge-based intensively competitive business environment. To avoid the detrimental consequences of knowledge loss, managers are urged to identify where knowledge stocks exist and how knowledge flows within their organisations by identifying knowledge holders among their employees. Although some studies have attempted to use different methods to measure knowledge at the organisational level, very few have addressed the individual knowledge holder. Moving from a critical literature review of the existing knowledge measurement approaches, this paper proposes a novel framework that enables organisations to measure individual knowledge in the business context using a set of metrics, which are subsequently validated via a series of in-depth interviews with senior managers. A summary of the managers’ views on individual knowledge measurement is presented, and reflections on the industry application of the proposed framework and recommendations for its improvement are also discussed. 相似文献
92.
Mohamed Ahmed Abdelmoaty M. A. Ibrahim N. S. Ahmed M. A. Abdelaziz 《Indian journal of clinical biochemistry : IJCB》2010,25(2):188-192
Quercetin (QE), one of natural flavanoid group, was widely distributed as a secondary metabolite in plant kingdom. It has
been believed that oxidative stress plays a role in the pathogenesis of diabetes mellitus (DM). The aim of the present study
was the evaluation of possible effects of QE on blood glucose and antioxidant enzymes in experimental streptozotocin (STZ)-induced
diabetes in rats. STZ was injected intraperitoneally with single dose of 50 mg/kg for diabetes induction. QE (15 mg/kg bw
day, intraperitoneal (i.p.) injection) was injected for 3 days prior to STZ administration; these injections were continued
to the end of the study (for 25 days). Glucose tolerance test and random plasma glucose were done for all animals. Cellular
antioxidant enzymes such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD) and catalase (CAT) activities were
measured in pancreatic homogenates. Quercetin had no effect on plasma glucose level of normal animals but its pre- treatment
was able to prevent diabetes induced by single intraperitoneal injection of streptozocintreated rats. Antioxidant enzyme activity
significantly decreased in STZ induced diabetic group. QE treatment significantly increased the antioxidant enzyme activities.
It could be concluded that quercetin, a flavonoid with antioxidant properties, exerting its beneficial antidiabetic effects. 相似文献
93.
This paper deals with the problem of model reference control for linear parameter varying (LPV) systems. The LPV systems under consideration depend on a set of parameters that are bounded and available online. The main contribution of this paper is to design an LPV model reference control scheme for LPV systems whose state-space matrices depend affinely on a set of time-varying parameters that are bounded and available online. The design problem is divided into two subproblems: the design of the coefficient matrices of the controller and the design of the gain of the state feedback controller for LPV systems. The singular value decomposition is used to obtain the coefficient matrices, while the linear matrix inequality methodology is used to obtain the parameter-dependent state feedback gain of the control scheme. A simple numerical example is used to illustrate the proposed design and a coupled-tank process example is used to demonstrate the usefulness and practicality of the proposed design. Simulation and experimental results indicate that the proposed scheme works well. 相似文献
94.
Thouraya Mhenni Lars Bojsen Michalsik Mohamed Arbi Mejri Narimen Yousfi Anis Chaouachi Nizar Souissi 《Journal of sports sciences》2017,35(9):912-920
This study investigated the two different time-of-day effect on team-handball-related short-term maximal physical performances. At two different time-of-day, fifteen young female team handball players performed different physical tests: HandGrip (HG) test, Ball-Throwing Velocity (BTV) test, Modified Agility T-test (MAT) and Repeated Shuttle-Sprint and Jump Ability (RSSJA) test. Rating of perceived exertion (RPE) scale was determined following the termination of the last test. Measurements were performed at two separate testing sessions (i.e., in the morning (7:00–8:30 h) and in the early evening (17:00–18:30 h)) in a randomised and counter-balanced setting on non-consecutive days. The results showed that HG (P = 0.0013), BTV (P = 0.0027) and MAT (P < 0.001) performances were better in the evening compared with the morning. During RSSJA, both best and mean sprint times were shorter in the evening compared to the morning (P < 0.001). Moreover, during the latter test, mean jump performance was higher in the evening compared to the morning (P = 0.026). However, there was no morning–evening difference in the best jump performance during RSSJA. Likewise, jump performance decrement was not affected by the time-of-day of testing. On the other hand, RPE fluctuated, with morning nadirs and afternoon/early evening highest values. The findings suggest that in female team handball players, team-handball-related short-term maximal physical performances were better in the afternoon than in the morning. 相似文献
95.
Mohamed Assaad Hamida Alain Glumineau Jesus de Leon 《Journal of The Franklin Institute》2012,349(5):1734-1757
In this paper, a sensorless speed control for interior permanent magnet synchronous motors (IPMSM) is designed by combining a robust backstepping controller with integral actions and an adaptive interconnected observer. The IPMSM control design generally requires rotor position measurement. Then, to eliminate this sensor, an adaptive interconnected observer is designed to estimate the rotor position and the speed. Moreover, a robust nonlinear control based on the backstepping algorithm is designed where an integral action is introduced in order to improve the robust properties of the controller. The stability of the closed-loop system with the observer–controller scheme is analyzed and sufficient conditions are given to prove the practical stability. Simulation results are shown to illustrate the performance of the proposed scheme under parametric uncertainties and low speed. Furthermore, the proposed integral backstepping control is compared with the classical backstepping controller. 相似文献
96.
Mohamed Taha Mohamed 《Teacher Development》2014,18(1):46-64
This research investigates aspects of epistemic beliefs of pre-service and in-service teachers in the United Arab Emirates, and how these beliefs might be related to factors such as teachers’ gender, location (where they live), and the subject they teach (humanities vs. science). A standardized Arabic version of the Epistemic Belief Inventory was administered to a group of 35 pre-service teachers and 52 in-service teachers. The results indicated that in-service teachers had more sophisticated beliefs than pre-service teachers on Certainty of Knowledge, Omniscient Authority, and Innate Ability dimensions. Also, male teachers were found to be less sophisticated than female teachers and teachers from rural areas tended to think in a simpler way than teachers from urban areas. Although there was no main effect of subject, it significantly modified the effects of gender and location. The data showed the multidimensional nature of epistemic beliefs, and were discussed in the context of Arab/Emirati culture. 相似文献
97.
Moussa Labbadi Yassine Boukal Mohamed Cherkaoui Mohamed Djemai 《Journal of The Franklin Institute》2021,358(9):4822-4847
In the present paper, the problem of designing a global sliding mode control scheme based on fractional operators for tracking a quadrotor trajectory is investigated. The model of the quadrotor system is given with disturbances and uncertainties. To converge in short finite time of the sliding manifold, a classical quadratic Lyapunov function was used and also a global stabilization of the quadrotor system is ensured. The proposed controller can be ensured the robustness against external disturbances and model uncertainties. Some scenarios are illustrated in this paper. Finally, a comparative study to three other controllers is provided to show the validity and feasibility of the proposed method. 相似文献
98.
Recent statistics on the use of mobile technology proclaim that the world is becoming mobile. People use their phones to socialize, to conduct business, to search for information, and more. For the first time in history, people around the world have the potential to learn from any location at their own convenience. But first, education systems must change, to facilitate mobile access to education. As this article describes, the most important change will be training teachers, both in pre-service programmes and through professional development, to use the technology to design and deliver education and to create bridges to informal learning. The article also describes some projects around the world that are helping to prepare teachers for the mobile world, and some pilot projects using the technology. Most such research, however, is limited to short-term studies focusing on learners’ satisfaction with mobile learning. Future studies must consider its long-term benefits and its impacts on performance and retention. As mobile technologies emerge, teachers have to keep up with the changes so that they can take advantage of the power of the technology to design and deliver education. 相似文献
99.
Maha A. Almuneef Mohamed Qayad Ismail K. Noor Majid A. Al-Eissa Fadia S. AlBuhairan Sarah Inam Christopher Mikton 《Child abuse & neglect》2014
There has been increased awareness of child maltreatment in Saudi Arabia recently. This study assessed the readiness for implementing large-scale evidence-based child maltreatment prevention programs in Saudi Arabia. Key informants, who were key decision makers and senior managers in the field of child maltreatment, were invited to participate in the study. A multidimensional tool, developed by WHO and collaborators from several middle and low income countries, was used to assess 10 dimensions of readiness. A group of experts also gave an objective assessment of the 10 dimensions and key informants’ and experts’ scores were compared. On a scale of 100, the key informants gave a readiness score of 43% for Saudi Arabia to implement large-scale, evidence-based CM prevention programs, and experts gave an overall readiness score of 40%. Both the key informants and experts agreed that 4 of the dimensions (attitudes toward child maltreatment prevention, institutional links and resources, material resources, and human and technical resources) had low readiness scores (<5) each and three dimensions (knowledge of child maltreatment prevention, scientific data on child maltreatment prevention, and will to address child maltreatment problem) had high readiness scores (≥5) each. There was significant disagreement between key informants and experts on the remaining 3 dimensions. Overall, Saudi Arabia has a moderate/fair readiness to implement large-scale child maltreatment prevention programs. Capacity building; strengthening of material resources; and improving institutional links, collaborations, and attitudes toward the child maltreatment problem are required to improve the country's readiness to implement such programs. 相似文献
100.
提出一种在车辆自组织网络(VANET)中应用的无线多跳视频传输实验系统的设计和实现方案及其对应的传输控制和路由选择协议.该系统将嵌入式Linux与IEEE 802.11n传输协议集成到ARM内核,由S3C6410主控模块、无线局域网网卡及LCD屏等构成.针对VANET的无线多跳视频传输场景,对视频编译码分别采用H.264和JPEG两种标准实现并对它们的压缩比、时延、传输丢包率等性能进行了理论分析和实验比较,进行了室内室外多种不同场景的实际测试.结果表明:所设计的多跳视频传输实验系统方案能够适应VANET等多种场景的应用,所提出的传输控制和路由选择协议能够保证视频传输的多跳和实时性要求. 相似文献