Observer design for constrained nonlinear systems with application to secure communication     

Mohamed F. Hassan 《Journal of The Franklin Institute》2014

In this paper, a constrained regularized least square (RLS) state estimator is developed for deterministic discrete-time nonlinear dynamical systems subject to a set of equality and/or inequality constraints. The stability of the estimation error is rigorously analyzed. The proposed estimator is then used to handle the important problem of secure communication. At the transmitting end, the output of the constrained unified chaotic system is used as a chaotic mask to achieve a satisfactory and typical secure communication scheme. The encrypted data signal is injected into the transmitter and simultaneously transmitted to the receiver through a public channel. At the receiving end, the constrained RLS estimator is used to reconstruct the states of the constrained unified chaotic system. Simulation results are presented to show the impact of the imposed constraints on the waveform and the pattern of the generated chaotic signal as well as the ability of the proposed estimator to synchronize the actual and estimated states of the constrained unified chaotic system. Moreover, the proposed estimator is applied to recover discrete signals such as digital images where computer simulation results are provided to show the effectiveness of the proposed estimation scheme.  相似文献   

Team learning in IT implementation projects: Antecedents and consequences     

Ali E. Akgün  Gary S. Lynn  Halit Keskin  Derya Dogan 《International Journal of Information Management》2014

This study investigates the antecedents and consequences of team learning, which is composed of information acquisition, dissemination, and implementation, in information technology (IT) implementation projects. By investigating 129 IT implementation project teams, we found that (1) information acquisition and information dissemination have a positive impact on project outcomes, such as speed-to-users, lower implementation cost, and operational effectiveness, and (2) team behavior and enabler variables, such as teamwork, team communication, interpersonal trust between team members, team commitment, and senior manager support, positively influence team learning. We also found that team anxiety moderates the relationship between team learning and project outcomes.  相似文献   

Abstracts of 41st National Conference of Association of Clinical Biochemists of India (ACBICON 2014)     

Abbas Ali Mahdi  Ghizal Fatima 《Indian journal of clinical biochemistry : IJCB》2014,29(1):1-2

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Perception of spiritual health: A qualitative content analysis in Iranian older adults     

Hosein Ajam Zibad  Farahnaz Mohammadi Shahboulaghi  Hassan Rafiey  Maryam Rassouli 《Educational gerontology》2017,43(1):21-32

The present study was performed with the aim to explain older people’s perceptions of spiritual health. It was conducted using the conventional content analysis method. Twelve individuals aged 60 years or older with normal cognition participated in the study using purposive sampling. Data were collected by in-depth interviews. Data analysis performed using standard method of thematic analysis.The average age of the study participants was 71.25 ± 9.48. The data analysis resulted in three main categories of spiritual insight, spiritual function, and spiritual affection. The spiritual insight included cognition of God and belief in Him, understanding of the divine religions and belief in them, self-cognition, cognition of the creation, and belief in the hereafter. This category included the two subcategories of spiritual cognition and spiritual belief. Spiritual function represented the interactions that the older people experienced in relations with God, themselves, and others. This category consisted of the subcategories of relationship with God, relationship with others, and self-cultivation. The spiritual affection included loving God and other humans and consisted of the three subcategories of spiritual affections to God, others, and oneself. This study presents in-depth data on the concept of spiritual health from older people’s viewpoints. These findings would help healthcare teams in designing appropriate interventions for older people’s health promotion. Also, by using the results of this research, health researchers design more appropriate tools for measuring spiritual health based on older people’s perception of the concept of spiritual health.  相似文献   

Examining the moderating effect of individual-level cultural values on users’ acceptance of E-learning in developing countries: a structural equation modeling of an extended technology acceptance model     

Ali Tarhini  Kate Hone  Xiaohui Liu  Takwa Tarhini 《Interactive Learning Environments》2017,25(3):306-328

In this study, we examine the effects of individual-level culture on the adoption and acceptance of e-learning tools by students in Lebanon using a theoretical framework based on the Technology Acceptance Model (TAM). To overcome possible limitations of using TAM in developing countries, we extend TAM to include subjective norms (SN) and quality of work life constructs as additional constructs and a number of cultural variables as moderators. The four cultural dimensions of masculinity/femininity (MF), individualism/collectivism, power distance and uncertainty avoidance were measured at the individual level to enable them to be integrated into the extended TAM as moderators and a research model was developed based on previous literature. To test the hypothesised model, data were collected from 569 undergraduate and postgraduate students using e-learning tools in Lebanon via questionnaire. The collected data were analysed using the structural equation modelling technique in conjunction with multi-group analysis. As hypothesised, the results of the study revealed perceived usefulness (PU), perceived ease of use (PEOU), SN and quality of work life to be significant determinants of students’ behavioural intention (BI) towards e-learning. The empirical results also demonstrated that the relationship between SN and BI was particularly sensitive to differences in individual-cultural values, with significant moderating effects observed for all four of the cultural dimensions studied. Some moderating effects of culture were also found for both PU and PEOU, however, contrary to expectations the effect of quality of work life was not found to be moderated by MF as some previous authors have predicted. The implications of these results to both theory and practice are explored in the paper.  相似文献   

Shaping global teacher identity in a short-term mobility programme     

Donna Tangen  Deborah Henderson  Jennifer Alford  Erika Hepple  Amyzar Alwi  Zaira Abu Hassan Shaari 《Asia-Pacific Journal of Teacher Education》2017,45(1):23-38

This article explores the shaping of Australian and Malaysian pre-service teachers’ possible selves in a short-term mobility programme. With the theory of possible selves, individuals imagine who they will become based on their past and current selves. The focus of the research was on pre-service teachers’ possible selves as global and culturally responsive teachers. The experiential learning through participation in the programme allowed participants to consider their future possible selves as teachers with a deeper understanding of diverse learners’ needs and how they might strive to address these needs in their own classrooms. The scaffolding of reflections in the programme encouraged the pre-service teachers to take on multiple perspectives, to step outside their comfort zones and in many ways to see the world from different eyes. The research found that through experiential learning in the short-term mobility programme both the Australian and Malaysian pre-service teachers gained in positioning their cultural selves currently and as future teachers, suggesting that there is merit in utilising the theory of possible selves in future research in the area of shaping teacher identity.  相似文献   

Exploring the use of the ICT in supporting dyslexic students’ preferred learning styles : A preliminary evaluation     

FatimaEzzahra Benmarrakchi  Jamal El Kafi  Ali Elhore  Sara Haie 《Education and Information Technologies》2017,22(6):2939-2957

Dyslexia is one of the most common learning disabilities. It is described as a disorder manifested by difficulty in learning to read despite conventional instruction, adequate intelligence, and sociocultural opportunity. It affects relatively about 7–10 % of the population across most languages and cultures. In this study, we explore the potential benefits offered by the use of Information and Communication Technology (ICT) to support dyslexic students by considering their preferred learning styles. In the current paper we administered the VAK and Honey & Mumford questionnaires to 28 Arabic students with ages between 8 and 10 years old. 8 students from dyslexic group and 20 students from control group were selected to assess and compare their preferred learning style. The implemented system focuses on dyslexia in Arabic language, especially in Arabic countries such as Morocco. Based on the results of the analysis of learning styles differences, we introduced an adaptive mobile learning to support and promote learning for dyslexic students. The aim of the study is to consider the relationship between dyslexia and learning style and to suggest a different learning way. Preliminary results show that the ICT has a valuable role in providing opportunities for learners with dyslexia to participate more fully in education.  相似文献   

Preparing a Data Scientist: A Pedagogic Experience in Designing a Big Data Analytics Course          下载免费PDF全文

Daniel Adomako Asamoah  Ramesh Sharda  Amir Hassan Zadeh  Pankush Kalgotra 《Decision Sciences Journal of Innovative Education》2017,15(2):161-190

In this article, we present an experiential perspective on how a big data analytics course was designed and delivered to students at a major Midwestern university. In reference to the MSIS 2006 Model Curriculum, we designed this course as a level 2 course, with prerequisites in databases, computer programming, statistics, and data mining. Students in the class were mostly seniors or at the graduate level, and had a strong technical and quantitative background. We include details of concepts covered in the course, as well as summaries of four major sample course assignments used. Some of the concepts covered include large‐scale data collection and management using the Hadoop ecosystem, stream mining, visual analytics, and social network analytics. Besides Hadoop, the course also introduced various IBM and Teradata big data tools. We show how the course modules align with the intended learning goals and course objectives. A post‐course survey indicated that the structure and organization of the course helped students clearly and concisely assimilate the course content.  相似文献   

H∞ dynamic observer-based fuzzy integral sliding mode control with input magnitude and rate constraints     

Zeinab Echreshavi  Mokhtar Shasadeghi  Mohammad Hassan Asemani 《Journal of The Franklin Institute》2021,358(1):575-605

This paper focuses on a systematic constrained fuzzy integral sliding mode controller design for a class of uncertain discrete-time nonlinear systems which can be represented as Takagi-Sugeno (T-S) fuzzy models. The contributions are to consider constraints on the control input amplitude and control input amplitude rate and to extend the existing pole-placement design technique for designing gain matrices of the fuzzy sliding surface. Moreover, a dynamic-gain observer along with ${\mathit{H}}_{\infty }$ performance is proposed for attenuating disturbance, which generalizes the existing results on the Proportional Observer (PO), the Proportional Integral Observer (PIO) and the dynamic observer (DO). Finally, the dynamic-observer-based constrained fuzzy integral sliding mode controller is designed. All the proposed design conditions are represented in terms of LMIs-based ones. The methods are studied for not only single-input single-output (SISO) but also multi-input multi-output (MIMO) systems. In the end, the proposed approaches are evaluated on practical and numerical systems to illustrate the superiority of the proposed control scheme.  相似文献   

The extent of concentration in journal publishing     

Fereshteh DIDEGAH  Ali GAZNI 《Learned Publishing》2011,24(4):303-310

This study examines the extent of concentration in the journal publishing industry. A number of aspects are considered: publishers, journal impacts, countries, and languages. For journals indexed in JCR from 1997 to 2009, just 0.2% of publishers produce 50% of journals and articles, and 0.3% of publishers account for the top 50% of citations, impact factors and immediacy indices. More than a half of publishers in JCR are from four countries: USA, UK, Germany and Japan. In addition, more than a half of journals come from the USA and UK. Examining the publishers' interactions in terms of buying and selling journals shows the extent of change by acquisition, and the acquisition links between publishers. The findings confirm that the international market of journal publishing is essentially dominated by a few publishers.  相似文献