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1.
Fadi Aloul Imran Zualkernan Ghaleb Husseini Ayman El-Hag Yousef Al-Assaf 《European Journal of Engineering Education》2015,40(1):32-51
Introductory engineering courses are either programme specific or expose students to engineering as a broad discipline by including materials from various engineering programmes. A common introductory engineering course that spans different engineering programmes raises challenges, including the high cost of resources as well as the lack of background courses of first-year students. This paper presents the design, implementation and evaluation of a first-year common engineering course that uses low-cost materials to expose students to a structured engineering design process. The course is explicitly designed to satisfy the Accreditation Board for Engineering and Technology criteria for engineering programmes. Our experience with the course shows that not only students are able to follow a structured design process successfully but we also believe that most of the ABET criteria are being delivered through the course. 相似文献
2.
Mathematical models are an approximate of physical systems and design procedures are only complete when modeling errors have been quantified. Uncertainties are incorporated in design procedure to compensate such discrepancies and to add robustness. This paper investigates the design problem of parameter-dependent switched observers for polytopic uncertain switched systems. State-space model is considered subject to time-varying uncertainties, and designated observer gains ensuring stability of overall system are also parameter-dependent. Synthesis procedure is demonstrated by employing ?∞ performance criteria which has become a standard for robust system design against external disturbances. This investigation is carried out in the framework of finite-time stability (FTS) and finite-time boundedness (FTB) which is the focus of researchers recently because of its apparent practical significance, especially after the emergent utilization of linear matrix inequalities. 相似文献
3.
Khalid M Yang WJ Kishwar N Rajput ZI Arijo AG 《Journal of Zhejiang University. Science. B》2006,7(6):459-466
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency （45% and 36% respectively）, as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium. 相似文献
4.
Imran Ghous Zhaoxia Duan Jahanzeb Akhtar Muhammad Jawad 《Journal of The Franklin Institute》2019,356(16):9407-9431
This paper aims to solve the problem of sliding mode control for an uncertain two-dimensional (2-D) systems with states having time-varying delays. The uncertainties in the system dynamics are constituted of mismatched uncertain parameters and the unknown nonlinear bounded function. The proposed problem utilizes the model transformation approach. By segregating the proper Lyapunov–Krasovskii functional in concert with the improved version of Wirtinger-based summation inequality, sufficient solvability conditions for the existence of linear switching surfaces have been put forward, which ensure the asymptotical stability of the reduced-order equivalent sliding mode dynamics. Then, we solve the controller synthesis problem by extending the recently proposed reaching law to 2-D systems, whose proportional part is appropriately scaled by the factor that does not depend on some constant terms but rather on current switching surface’s value, which in turn ensures the faster convergence and better robustness against uncertainties. Finally, the proposed results have been validated through an implementation to a suitable physical system. 相似文献
5.
Muhammad Zubair Iqbal 《广播与电子媒介杂志》2017,61(2):449-466
The media-terrorism nexus needs further exploration. This article is a qualitative analysis of the coverage of London Attacks, 2005 by the British TV news channels. It aims to investigate and to empirically ascertain the veracity of the media-terrorism-symbiotic-relationship notion. The research draws a comparison with a similar study of the coverage of Mumbai attacks, 2008 and maintains that when the terrorist event happens on British soil, the symbiotic relationship theory is not verified completely. It concludes that British TV news channels, while reporting the home event of terrorism, do not overly focus on the theme of awe and terror. Instead, they are more responsible, careful, and nationalistic while covering the events of terrorism. 相似文献
6.
We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards. 相似文献
7.
Learning materials recommendation using good learners’ ratings and content-based filtering 总被引：1，自引：0，他引：1
Khairil Imran Ghauth Nor Aniza Abdullah 《Educational technology research and development : ETR & D》2010,58(6):711-727
The enormity of the amount of learning materials in e-learning has led to the difficulty of locating suitable learning materials
for a particular learning topic, creating the need for recommendation tools within a learning context. In this paper, we aim
to address this need by proposing a novel e-learning recommender system framework that is based on two conceptual foundations—peer
learning and social learning theories that encourage students to cooperate and learn among themselves. Our proposed framework
works on the idea of recommending learning materials with a similar content and indicating the quality of learning materials
based on good learners’ ratings. A comprehensive set of experiments were conducted to measure the system accuracy and its
impact on learner’s performance. The obtained results show that the proposed e-learning recommender system has a significant
improvement in the post-test of about 12.16% with the effect size of 0.6 and 13.11% with the effect size of 0.53 when compared
to the e-learning with a content-based recommender system and the e-learning without a recommender system, respectively. Furthermore,
the proposed recommender system performed better in terms of having a small rating deviation and a higher precision as compared
to e-learning with a content-based recommender system. 相似文献
8.
Hamdi Echeikh Ramzi Trabelsi Atif Iqbal Med Faouzi Mimouni 《Journal of The Franklin Institute》2018,355(5):2112-2141
High performance multiphase motor drive requires precise knowledge of the state quantities and the machine parameters. Access to these state quantities is through measurement using sensors whose accuracy is paramount to achieve the performance level required by industrial applications. However, the problems of the parameters variations, inaccessibility to the measurement of some states, no-observability of the machine in some regions, the cost of the sensors and their lack of precision, make this very difficult task. To address these problems, it is necessary to resort to soft sensors through the design of observers and estimators. In multiphase induction motor drive, the observation problem arises especially for rotor flux that is not accessible for measurement. About the parameters variations, the rotor resistance and the stator resistance are the most critical parameters of the machine because their influence is crucial for the control and observation. The change in the resistances can be as large as 40–50% of the rated value, which may affect the control adversely. This paper develops a new structure of an adaptive sliding mode observer based on an online estimation of the rotor resistance value in order to avoid the effect of its variation in the rotor flux oriented control. The results show convergent (the errors in the transient and steady states are 5% and 1%, respectively) behavior of the drive using the proposed control scheme for large rotor resistance variation under loaded condition. The stability of the drive is proved using Lyapunov criteria. The simulation results are validated using real time implementation. 相似文献
9.
Amer M. Magableh Osamah S. Badarneh Imran Shafique Ansari Taimour Aldalgamouni 《Journal of The Franklin Institute》2018,355(14):6877-6888
Transmit antenna selection with maximal ratio combining at the receiver (TAS/MRC) is a promising technique that can be used to avoid the hardware complexity of multiple input multiple output (MIMO) system without jeopardizing the diversity gain. The generalized Gaussian distribution (GGD) is used to model different kinds of additive noise including Gaussian, Laplacian, uniform, and impulsive. In this paper, we study the bit error performance of TAS/MRC system assuming flat Rayleigh fading channels perturbed by additive white generalized Gaussian noise (AWGGN). To this end, we provide a closed form expression for the average bit error rate of coherent modulation techniques in terms of Mejier’s G function that is readily available in many commercial mathematical software packages like MATLAB and Mathematica. Moreover, we study the asymptotic behavior of the BER at high signal to noise ratio (SNR). Analytical results are verified by simulation. 相似文献
10.