The growing interest in the use of chaotic techniques for enabling secure communication in recent years has been motivated by the emergence of a number of wireless services which require the service provider to provide low bit error rates (BER) along with information security. This paper investigates the feasibility of using chaotic communications over Multiple-Input-Multiple-Output (MIMO) channels. While the use of Chaotic maps can enhance security, it is seen that the overall BER performance gets degraded when compared to conventional communication schemes. In order to overcome this limitation, we have proposed the use of a combination of Chaotic modulation and Alamouti Space Time Block Code. The performance of Chaos Shift Keying (CSK) wi

The choice of binary Pseudonoise (PN) sequences with specific properties, having long period high complexity, randomness, minimum cross and auto- correlation which are essential for some communication systems. In this research a nonlinear PN generator is introduced . It consists of a combination of basic components like Linear Feedback Shift Register (LFSR), ?-element which is a type of RxR crossbar switches. The period and complexity of a sequence which are generated by the proposed generator are computed and the randomness properties of these sequences are measured by well-known randomness tests.

The goal of this work is demonstrating, through the gradient observation of a   of type linear ( -systems), the possibility for reducing the effect of any disturbances (pollution, radiation, infection, etc.) asymptotically, by a suitable choice of related actuators of these systems. Thus, a class of  ( -system) was developed based on finite time  ( -system). Furthermore, definitions and some properties of this concept -system and asymptotically gradient controllable system ( -controllable) were stated and studied. More precisely, asymptotically gradient efficient actuators ensuring the weak asymptotically gradient compensation system ( -system) of known or unknown disturbances are examined. Consequently, under convenient hypo

This paper proposes a novel finite-time generalized proportional integral observer (FTGPIO) based a sliding mode control (SMC) scheme for the tracking control problem of high order uncertain systems subject to fast time-varying disturbances. For this purpose, the construction of the controller consists of two consecutive steps. First, the novel FTGPIO is designed to observe unmeasurable plant dynamics states and disturbance with its higher time derivatives in finite time rather than infinite time as in the standard GPIO. In the FTGPO estimator, the finite time convergence rate of estimations is well achieved, whereas the convergence rate of estimations by classical GPIO is asymptotic and slow. Secondly, on the basis of the finite and fast e

Abstract\

The developed financial infrastructure is one of the most important elements for achieving stable financial system in a country. The importance of developed financial infrastructure comes from its role in create economic and financial context attractive for foreign investments. Thus, this paper aims first to measure an index of financial infrastructure, and secondly, to gauge the nexus between the developed financial infrastructure and foreign investments inflow in Malaysia and Indonesia. We estimate the index of financial infrastructure by using different indicators such as (the institutional environment, access to finance, legal environment, and others).

By using the G

This study aims at recognizing the levels of comprehension of the students of basic schools to the concepts of mathematical geometric and discovering the existing of the differences among students in the level of understanding of the concepts of mathematical geometrical which is due to the change of gender.

The sample of the study is the students of Basic schools, eight level in the basic school of Erbil city, particularly 7-8-and 9 levels in the academic year 2013-2014. The sample consists of 444 students in both genders238 males and 206 females.

The tool of the study is test sheet included 20 items of multiple choice.  The items are valid since are given to a jury of expert

Abstract

In light of the great technological development and the emergence of globalization has increased global competition, where it became competitive exercise pressure on all sectors. In light of this companies mast enviorment depend on the means that keeps them on the competitive position through access to information about competitors in order to help them to draw a strategy that will achieve a competitive edge either through excellence or reduce the costs of their products and this means intelligence competitive and reverse engineering that help to gain information on competitors analyze and put of the decision-maker From this point formed the idea of ​​research in the statement of the role of

Recently, there has been a major trend towards environmental issues and concern for the green product because traditional products cause serious environmental impacts such as reduced resources, global warming, energy consumption, emissions and other environmental damage. Under these developments, economic units are looking for cost-effective technologies that reduce the cost of a green product that has four main dimensions: reducing energy, reducing resource consumption, preventing pollution, and using renewable energy while not compromising quality and satisfying customers in order to enhance competitive advantage.

This research will address one of the most important cost-effective green technologies, Gr