In this paper, we discuss physical layer security techniques in downlink networks, including eavesdroppers. The main objective of using physical layer security is delivering a perfectly secure message from a transmitter to an intended receiver in the presence of passive or active eavesdroppers who are trying to wiretap the information or disturb the network stability. In downlink networks, based on the random feature of channels to terminals, opportunistic user scheduling can be exploited as an additional tool for enhancing physical layer security. We introduce user scheduling strategies and discuss the corresponding performances according to different levels of channel state information (CSI) at the base station (BS). We show that the avai

Authentication is the process of determining whether someone or something is, in fact, who or what it is declared to be. As the dependence upon computers and computer networks grows, the need for user authentication has increased. User’s claimed identity can be verified by one of several methods. One of the most popular of these methods is represented by (something user know), such as password or Personal Identification Number (PIN). Biometrics is the science and technology of authentication by identifying the living individual’s physiological or behavioral attributes. Keystroke authentication is a new behavioral access control system to identify legitimate users via their typing behavior. The objective of this paper is to provide user

In this work we fabrication holographic optical element diffraction grating thickness 40?m and mirror90?m by using dichromated gelatin,to perform that we have to use the Nd-yaG laser doubling frequency of wavelenght (532)nm and its powers of (80)mWatt.we have studyed the thickness and concentration dichromat effect in mirror reflaction ,effect of angle of reconstruction beam in band width and diffraction efficiency ,study effect gelatin hardener of the diffraction efficiency.

In this paper the queuing system (M/Er/1/N) has been considered in equilibrium. The method of stages introduced by Erlang has been used. The system of equations which governs the equilibrium probabilities of various stages has been given. For general N the probability of j stages of service are left in the system, has been introduced. And the probability for the empty system has been calculated in the explicit form.

Studied red beetle life on each of the yen and wheat durum wheat, barley, corn, rice, chickpeas, ground peanuts and beans in Living situation constant temperature and relative humidity of 65% for a period of 66 days was the life cycle of the insect different from one substance to another ....

The research starts from a fundamental problem about how top management team can realize the uncertainty. Strategic conversation has been introduced as a way for top management team to deal with uncertainties. Within the current research model, the strategic conversation was considered as an independent variable and uncertainty as dependent variable. The researcher used the survey method by distributed a questionnaire in the Administration and Economics College, University of Baghdad. Samples are 40 faculty participant of scientific committee members were distributed in seven scientific departments. The data were statistically analyzed by mean and the standard deviation. The hypotheses were tested through the use of correlation and regressi

Racism is a serious issue that impacts a lot of people around the world. Since slavery days, racial discrimination has been increasing to abhorrent levels in relation to black people. The aim of individual psychology by Alfred Adler is to study human behaviour by situating it in the social context which makes his writing ideal to explanation of racism. This paper aims to study racism in Roy Williams’ Fallout from the perspective of Alfred Adler’s theory. Alfred Adler's individual psychology emphasizes the importance of social factors in shaping individual behavior, including the ways in which individuals form their sense of self and identity. This makes it a valuable framework for understanding the complex social and psychological facto

Assessment of the in service behavior of asphalt stabilized subgrade soil under environmental impact has got little attention by the research workers. However, the sustainability of the roadway depends mainly on the welfare of its subgrade soil condition. In this work, Gypseous soil was stabilized with asphalt emulsion for subgrade usage, the durability of the mixture has been assessed in term of its ability to maintain the compressive strength when practicing the environmental impacts. Specimens of 38 mm in diameter , and 76 mm in height have been prepared with various water-asphalt percentages, and subjected to 30 cycles of (freezing-thawing), (heating-cooling) and (wetting-drying) processes. Specimens have been tested for unconfined comp