Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at

The work in this paper focuses on the system quality of direct and coherent communication system for two computers. A system quality is represented by Signal to Noise ratio (SNR) and Bit Error Rate (BER). First part of the work includes implementation of direct optical fiber communication system and measure the system quality .The second part of the work include implementation both the( homodyne and heterodyne)coherent optical fiber communication system and measure the system quality . Laser diode 1310 nm wavelength with its drive circuit used in the transmitter circuit . A single mode of 62.11 km optical fiber is selected as transmission medium . A PIN photo detector is used in the receiver circuit. The optical D-coupler was u

Abstract
An optoelectronic system for fog detection and visibility technique is presented .The idea of this research is based on the measurement of the atmospheric visibility by using an infrared beam emitter from LED diode. The optical scattering is used as a method to calculate the visibility. This method is applied at forward scattering within a foggy atmosphere, which is modern and has great importance for measuring visibility in seaports, airports, public roads and highways. In this paper we focus on the description of the system, principles of its operation and some results of field tests.
Keywords: fog sensor, visibility sensor, backscattering, forward scattering.

هدفت الدراسة الحالية التعرف على البلادة العاطفية لطلبة الجامعة وكذلك التعرف على معنوية الفروق في البلادة العاطفية تبعاً لمتغيري: النوع (ذكور-اناث) والتخصص الدراسي (علمي –انساني) ، تآلفت عينة الدراسة من (400) طالب وطالبة موزعين بالتساوي حسب النوع والتخصص الدراسي تم اختيارهم عشوائيا من طلبة الجامعة، استخدمت الباحثة مقياس البلادة العاطفية من (اعداد الباحثة) وبعد تطبيق المقياس على عينة البحث واستخراج البيانات با

       The present research aims to know :

 The level of Cognitive failures, information processing styles, and the problem-solving among the university students ,so it is aims to know the contribution of cognitive failures on the information processing styles and problem-solving, the research sample was (400) males and females student  from the University of Wasit chosen randomly from both gender and for the study of the morning and evening .So  these scales had been used as a research tool (failures cognitive scale ,the scale of information processing styles , and the scale of problem solving) , and by using the statistical m

Current research strives to achieve the following aims:

1. Develop a scale for dominant values of Tikrit university students.
2. Measuring the dominant of Tikrit university students.
3. Identifying the significant differences among dominant values of Tikrit university students according to(sex, specialty, time).
4. Measuring the dominant values of each one of the six fields of the scale.
5. Identifying the differences in dominant values of each field according to the sex variables.

The current research has limi

أولاً: مشكلة البحث:

للتربية دوراً أساسياً في تكوين الإنسان ليصبح قادراً على الإسهام الحضاري، ودفع عجلة التنمية إلى الأمام. وينظر للتربية حالياً بأنها عملية توثيق الصلة بين الناشئ والبيئة في ظروف معينة تعينه على النمو في الاتجاه المرغوب فيه. ويأتي الجانب المعرفي في مقدمة جوانب النمو، فهو المسؤول عن بناء شخصية الفرد وأسلوب تفكيره (سعيد، 1989، ص28). فضلاً عن كونه الخاصية الراقية عند الإنسان التي

Suffering of modern man in all societies of psychological problems, social, economic and professional as a result of the evolution of massive technological and rapid disable individual from pursuing it as well as changes caused to human values​​, and these problems psychological problem of loneliness, the loneliness psychological state unique to the human from other organisms because of having social system, affected by and affects it, any defect may occur in the ties that bind man to other children of sex or any change occurs in the social system, reflected on the individual, and the resulting disruption in the social nature syndrome among individuals, what breeds they have the feeling of is

The current search aims to identify First: To measure the level of authoritarian personality among the students of the sample as a whole. Second: Measurement of differences in the level of authoritarian personality among students in the middle school according to the following variables 0.Science (literary, scientific) 8. Sex (male - female) Third: the level of control site level among the students of the sample as a whole. Ra'aa: Measurement of differences in the level of the control site among junior students according to the following variables 0.Science (literary, scientific) 8. Sex (male - female) Fifth: Explain the relationship between the authoritarian personality and the locus of control among the students of the research sample.