Adaptive output feedback neural network control of uncertain non-affine systems with unknown control direction

This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. The proposed controller is designed based on strict-positive-real (SPR) Lyapunov stability theory to ensure the asymptotic stability of the closed-loop system. Finally, two simulation studies are presented to demonstrate the effectiveness of the developed scheme.     

A new continuous action-set learning automaton for function optimization

In this paper, we study an adaptive random search method based on continuous action-set learning automaton for solving stochastic optimization problems in which only the noise-corrupted value of function at any chosen point in the parameter space is available. We first introduce a new continuous action-set learning automaton (CALA) and study its convergence properties. Then we give an algorithm for optimizing an unknown function.     

An investigation of the Gregorian chronology of early Islamic history : A Pilot Study

This pilot study presents a lunar and Gregorian chronology of the Sira, that is the biography of the prophet Muhammad. The paper discusses the problems surrounding the chronology of very early Islamic history, namely, the pre‐Hijra era. This history is not covered by the Hijra calendar, and therefore, historians dated its events using other primitive dating systems, resulting in considerable difficulties and inaccuracies when comparing Gregorian dates of this early Islamic history. In order to overcome this problem and establish an accurate chronology of the early Islamic history, the introduction of a new lunar calendar (the Muhammadi calendar) which starts with the birth month and year of the prophet Muhammad, and covers all Islamic history including the pre‐Hijra era, is suggested. The Muhammadi calendar was used to study the earliest three versions of the Sira. All dated events of the Sira were compiled from these sources and presented, for the first time, according to their historical order. The Muhammadi dates of these events were then calculated. For the first time, a computer program was designed to convert the Muliammadi dates to their Christian equivalent. The program was then used to compute the Gregorian dates of the events of the Sira.     

Linear-constant log-map,a fast accurate algorithm for map decoding

This paper proposes a new approximation to be used for the correction function in the turbo decoding algorithm, called Linear-Constant-log Map. Max-log Map, Linear-log Map and Constant-log Map are the well known simplified versions of Jacobi-log Map (Maximum a Posteriori) algorithm already in use but they cannot meet a proper performance in term of output BER and clock consumption of the CPU decoding encoded bits. The proposed algorithm first breaks the correction function domain of the Jacobi logarithm to three subsections by determining the border points between these sections and then uses a linear function and two constant values as an approximation of this function. Using an AWGN channel model, simulation results show that the new algorithm is almost more than six times faster than Jacobi-log Map algorithm with a Bit Error Rate (BER) very close to it.     

Aesthetic Modernism in the Post‐Colony: The Making of a National College of Art in Pakistan (1950–1960s)

With the formation of Pakistan as a modern Islamic republic in 1947, the institutions of art and design education were transformed under the sway of modernization theories of development. A conceptual and physical infrastructure was put in place to modify existing institutions and to create new ones for encouraging modern art and artists in the country. The 1950s saw major developments taking place in the former Mayo School of Art which was upgraded to the National College of Arts to train designers, artists and architects to meet the requirements of a new nation. The distinction between arts and crafts formed the discourse through which the changes in art education were articulated. The process of change unleashed in art education is emblematic of the changes taking place in the other sectors of economy and culture. The Bauhaus influence which formed the initial impulse to bring artists and craftsmen in the service of national industry gave way to the competing fine art movements in painting resulting in abandoning the synthesis of arts and crafts envisaged in the earlier approaches to art education.     

Effect of deposition parameters on mechanical properties of TiN films coated on 2A12 aluminum alloys by arc ion plating (AIP)

1 Introduction Weight saving materials such as aluminum and its alloys are becoming increasingly important and have been attracting increasing attention over the past decade, specially in the automotive, aerospace and chemical industries, and electrical devices because of their high strength-to-weight ratio, high electrical and thermal conductivities, processability and recyclability and good resistance to degradation in some corrosive environments [1,2]. In the automotive industry, there is d…     

Policies of global English tests: test-takers’ perspectives on the IELTS retake policy

Globalized English proficiency tests such as the International English Language Testing System (IELTS) are increasingly playing the role of gatekeepers in a globalizing world. Although the use of the IELTS as a ‘policy tool’ for making decisions in the areas of study, work and migration impacts on test-takers' lives and life chances, not much is known about its own policy and policy logic. With the growing call for listening to test-takers' voices, specific policy aspects of the test have recently been scrutinized. This article seeks to contribute to this area by drawing on test-takers' perspectives on the IELTS retake policy and developing an understanding of how policies of global English tests are perceived, interpreted and given new meanings by its key stakeholders. Although the truth-value of the emic views of test-takers may be debated, their experiences and perceptions problematize the reliability claims of the testing agency by locating commercial motives at the center of their policy and thereby raising theoretical, professional and ethical questions.     

The spread of private tutoring in English in developing societies: exploring students’ perceptions

ABSTRACT

Although research on private tutoring has gained visibility in recent years, private tutoring in English (PT-E) has not received notable attention. This paper examines students’ perceptions of PT-E in Bangladesh in terms of its necessity and helpfulness, peer pressure in PT-E participation and ethicality of PT-E practice and government intervention. Our analysis of survey data (N?=?572) leads to characterising PT-E and explaining the reasons for its popularity. As a popular learning space beyond formal schooling, PT-E is available in various forms and quality catering to the purchasing power of different social groups. We argue that students may resort to PT-E not because of its proven effectiveness but because of their declining faith in school English teaching. The paper contributes to our understanding of the complex interactions between the curricular (school) and non-curricular (PT-E) settings and family socioeconomic resources in the teaching of English as a globally desired language.     

Data-based modeling and estimation of vehicle crash processes in frontal fixed-barrier crashes

As a complex process, vehicle crash is challenging to be described and estimated mathematically. Although different mathematical models are developed, it is still difficult to balance the complexity of models and the performance of estimation. The aim of this work is to propose a novel scheme to model and estimate the processes of vehicle-barrier frontal crashes. In this work, a piecewise model structure is predefined to represent the accelerations of vehicle in frontal crashes. Each segment in the model is corresponding to the energy absorbing component in the crashworthiness structure. With the help of Ensemble Empirical Mode Decomposition (EEMD), a robust scheme is proposed for parameter identification. By adjusting the model structure and parameters according to the initial velocity, crash processes in different conditions are estimated effectively. The estimation results exhibit good agreement with finite element (FE) simulations in three different cases. It is shown that, the proposed model keeps low complexity. Furthermore, the structure information of vehicle is involved in improving the accuracy and ability of crash estimation.     

Florida public hurricane loss model: Research in multi-disciplinary system integration assisting government policy making

Homeowner insurance rate making is an important public policy issue in the State of Florida. The State of Florida has over 2 trillion dollars of residential properties exposed to hurricane risk. The State has declared that it shall adopt public policy to encourage the use of sophisticated actuarial methods to assure that consumers are charged lawful insurance rates (Section 627.0628(1)(a)). To that effect, the State's insurance regulatory agency, the Florida Office of Insurance Regulation (OIR), sponsored the development of a Florida Public Hurricane Loss Model (FPHLM) to assess the risk and project insured residential losses. The FPHLM is an open and public model that has been developed primarily by university experts without influence from either the insurance industry or the state regulators. It is open to public scrutiny and provides an understandable baseline to check the assumptions as well as the outputs of the proprietary models. The FPHLM thus makes the rate evaluation process more objective and less political. It enables the state to justify rejecting or accepting rate increases based on an independent and transparent model, rather than a process that can be influenced politically. As a multi-disciplinary large scale research project with an iterative and incremental development cycle, the FPHLM system development and integration faced numerous challenges varying from technical factors to project management aspects. This paper will discuss the research experiences accumulated during the development of the FPHLM and the impact it has had on the homeowner insurance rate filing process in the State of Florida.