Citizens as consumers: Profiling e-government services’ users in Egypt via data mining techniques   总被引：1，自引：0，他引：1  

Mohamed M. Mostafa  Ahmed A. El-Masry 《International Journal of Information Management》2013

This study uses data mining techniques to examine the effect of various demographic, cognitive and psychographic factors on Egyptian citizens’ use of e-government services. Data mining uses a broad family of computationally intensive methods that include decision trees, neural networks, rule induction, machine learning and graphic visualization. Three artificial neural network models (multi-layer perceptron neural network [MLP], probabilistic neural network [PNN] and self-organizing maps neural network [SOM]) and three machine learning techniques (classification and regression trees [CART], multivariate adaptive regression splines [MARS], and support vector machines [SVM]) are compared to a standard statistical method (linear discriminant analysis [LDA]). The variable sets considered are sex, age, educational level, e-government services perceived usefulness, ease of use, compatibility, subjective norms, trust, civic mindedness, and attitudes. The study shows how it is possible to identify various dimensions of e-government services usage behavior by uncovering complex patterns in the dataset, and also shows the classification abilities of data mining techniques.  相似文献   

Assessment of Some Biochemical Oxidative Stress Markers in Male Smokers with Chronic Periodontitis     

Abdul Samad Aziz  Madhav Govind Kalekar  Adinath Narayan Suryakar  Tabita Benjamin  Milsee Jaya Prakashan  Bijle Mohammed Nadeem Ahmed  Mehmood Sayyad 《Indian journal of clinical biochemistry : IJCB》2013,28(4):374-380

The present study aims to assess and compare the biochemical oxidative stress markers in male smokers and non-smokers with chronic periodontitis. One hundred thirty-four male chronic periodontitis patients and 64 apparently healthy male volunteers were recruited for the study. The periodontal status was evaluated by measuring gingival index, plaque index, papillary bleeding index and clinical attachment loss using UNC-15 probe. The biochemical markers estimated were total antioxidant capacity, RBC-superoxide dismutase, glutathione peroxidase, vitamin C, malondialdehyde and C-reactive protein. The obtained results indicate higher oxidative stress in chronic periodontitis. Smokers with chronic periodontitis show significantly higher periodontal clinical parameters and relatively higher systemic oxidative stress. Vitamin C estimation may be an important biochemical parameter in conjunction with clinical parameters for diagnosis of chronic periodontitis in smokers.  相似文献   

Pre-service teachers’ perceptions of effective inquiry instruction: are effective instruction and effective inquiry instruction essentially the same?     

Mark W. Aulls  Ahmed Ibrahim 《Instructional Science》2012,40(1):119-139

This multiple case study examined pre-service teachers perceptions of effective post-secondary instruction. Pre-service teachers were asked to write essays describing an effective teacher of their choice. Twenty-one essays were randomly selected. Data analysis involved open coding of each essay, content analysis of each essay using Anderson and Burns’ (Research in classrooms: The study of teachers, teaching, and instruction (1st ed.). Oxford, England; New York: Pergamon Press, 1989) empirically derived dimensions of instruction, and effect size analysis of student and teacher roles. Instructional components were identified that differentiate between effective inquiry instruction and effective instruction. Effective inquiry instruction was associated with more and different teacher and student roles, more activities as part of instruction, and more student small group discussion than was effective instruction.  相似文献   

How many equivalent resistances?     

Sameen Ahmed Khan 《Resonance》2012,17(5):468-475

It is straightforward to construct the set of equivalent resistance for circuits constructed from a bunch of four or five equal resistors. But as the bunch size increases it becomes difficult to find the order of the set of equivalent resistances. Even the computer programs runs out of memory. Here we present an analytical result using simple mathematical machinery. The size of the set is shown to be less than 2.618 ⁿ .  相似文献   

On Cocoons,Consciousness, and Courage: Preparing Justice-Oriented Teacher Educators Through Critical Pedagogies     

Jamy Stillman  Kathryn Struthers Ahmed  Erika Castañeda-Flores 《The Educational forum》2013,77(4):432-452

In this article, we share findings from a 3-year project in which novice teacher educators participated in Freirean culture circles and Boalian Theatre of the Oppressed (teatro) in order to critically explore the work of justice-oriented teacher education. Anchored in one of the project’s most resonant scenarios, the article illustrates how teatro cultivated among participants courage to confront injustice, while also shedding light on the complexities teacher educators may face when attempting to facilitate teacher learning, particularly when such learning is centered on equity and justice.  相似文献   

Dynamic voltage regulation and power export in a distribution system using distributed generation     

Aamir Hanif  Muhammad Ahmed Choudhry 《浙江大学学报(A卷英文版)》2009,10(10):1523-1531

The major aim of power quality （PQ） enhancing techniques is to maintain a specified voltage magnitude at a desired frequency for sensitive loads irrespective of faults on the power distribution network. The dynamic voltage restorer （DVR） is a device used to mitigate voltage sags to regulate load voltage. This paper presents a mathematical model for leading series voltage injection to mitigate sags thereby achieving the improvement of the utility power factor as well as power sharing between the DVR and utility. The power sharing will be as per requirement to compensate the sags considering the available distributed generation （DG）. The approach of mitigating voltage sags using the concept of leading series voltage injection is suitable for those locations where phase shift in the voltage will not cause any problem. The MATLAB/SIMULINK SimPowerSystem toolbox has been used to obtain simulation results to verify the proposed mathematical model.  相似文献   

The major players in adaptive immunity     

Asma Ahmed  Banishree Saha  Anand Patwardhan  Shwetha Shivaprasad  Dipankar Nandi 《Resonance》2009,14(6):610-621

Our immune system, by and large, does a fine job in protecting us from opportunistic and infectious microbes, potential carcinogens and allergens. It is therefore crucial to understand the organization of the immune network. This article focuses on some important features and key players involved in adaptive immune response. The first part of the article dealt with the humoral immune response mediated mainly by immunoglobulins produced by the B cells. The second part deals with T cells, the Major Histocompatibility Complex (MHC)-encoded molecules, and Recombination Activating Genes (RAG) responsible for generating diverse B-cell receptors (BCR) and T-cell receptors (TCR). With the advent of newer and smarter infectious agents, it is important to understand the working of the immune network as more research in this area may facilitate the development of better protective strategies.  相似文献   

Threshold behavior in a stochastic delayed SIS epidemic model with vaccination and double diseases     

Qun Liu  Daqing Jiang  Tasawar Hayat  Ahmed Alsaedi 《Journal of The Franklin Institute》2019,356(13):7466-7485

In this paper, we investigate the threshold dynamics of a stochastic delayed SIS epidemic model with vaccination and double diseases which make the research more difficult. We establish sufficient conditions for extinction and persistence in the mean of the two diseases. We also obtain the threshold between persistence in the mean and extinction of the stochastic system. It is shown that: (i) time delay and environmental white noise have important effects on the persistence and extinction of the two diseases; (ii) the two diseases can coexist under certain conditions. Finally, some numerical simulations are provided to demonstrate the analytical results.  相似文献   

Graph theory-based finite-time synchronization of fractional-order complex dynamical networks     

Hong-Li Li  Jinde Cao  Haijun Jiang  Ahmed Alsaedi 《Journal of The Franklin Institute》2018,355(13):5771-5789

This paper considers the finite-time synchronization problem for a class of fractional-order complex dynamical networks (FOCDNs). By utilizing the properties of fractional calculus and fractional-order comparison principle, we propose a new lemma. Base on the new lemma, some analysis techniques and algebraic graph theory method, some novel criteria are given to ensure finite-time synchronization of FOCDNs, and the upper bound of the setting time for synchronization is estimated. At last, numerical simulations are given to verify the effectiveness of the obtained results.  相似文献   

An optimization methodology of susceptance variation using lead-lag controller for grid connected FSIG based wind generator system     

Ashik Ahmed  Md. Mehedi Hassan Galib  Shafi Md. Kawsar Zaman  Golam Sarowar 《Journal of The Franklin Institute》2018,355(1):197-217

In wind power system, low frequency oscillations are observed due to imbalance between mechanical input and electrical output. Hence, variable susceptance controllers are being adopted to mitigate these oscillations. However, improper modulation of control parameters also leads to system instability. Therefore, we propose an optimization methodology for mitigating low frequency oscillations in wind power generation system. To visualize our methodology, we use a lead-lag type variable susceptance controller for fixed speed induction generator (FSIG) based wind generation system. Then, we optimize gain and time constants of lead-lag controller using three optimization algorithms: particle swarm optimization (PSO), genetic algorithm (GA), and flower pollination algorithm (FPA). Later, we perform non-linear time domain simulation and quantitative analysis to find average fitness, standard deviation, run time, and iteration number for these optimization algorithms. Moreover, non-parametric statistical analysis, such as Kolmogorov–Smirnov and Wilcoxon signed-rank tests are employed for identifying statistically significant differences among these algorithms.  相似文献