Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less numb

Suffer most of the facilities of the high cost of inventory , which affects the high cost of the product and thus affects many administrative decisions , as well as suffer the facilities of the systems developed by the provisions of inventory control , and this problem is exacerbated in the construction sector where the inventory in the form of Construction spin of the Year for another it becomes difficult to control the cost effectively , and is the research problem in question follows: What are the implications of the use of the system in time inventory accounting system for the contracting company does kills Alrkaah to the provisions of the cost of inventory and what is the optimal approach to inventory control ? Find assumed

The last four decades have witnessed a number of rapid and successive international changes in terms of future impacts and orientations. International economy has transformed into a competitive small village due to the information technology revolution and the liberation processes and the economic openness that the market witnesses, there became one market and the activists in this international market are not governments only but rather international organizations and huge multinational corporations where each spares no effort to take every opportunity and face challenges within the frame of  removing all impediments and release transactions under the auspices of  these global developments, the idea of creating Islamic

The research goes to clarifying the system of values ​​in dialogue with the violator through an inspection of our cultural heritage, and our inherent religious values. Al-Rashidah, and this position is represented in their various and varied dialogues with the Kharijites, whether that was at the beginning of their appearance - as is the case in the dialogue of Ali and Ibn Abbas, may God be pleased with them - or after the formation of their teams and the strength of their thorns, as in the dialogue of Ibn al-Zubayr and Jabir bin Abdullah, may God be pleased with them.

In these dialogues, I found important values ​​in the dialogue, which it is good to draw upon and work on, especially with the extremist currents in our tim

Abstract

One of the most suitable materials to be used in latent heat thermal energy storage system (LHTES) are Phase change materials, but a problem of slow melting and solidification processes made many researchers focusing on how to improve their thermal properties. This experimental work concerned with the enhancing of thermal conductivity of phase change material. The enhancing method was by the addition of copper Lessing rings in phase change material (paraffin wax). The effect of diameter for the used rings was studied by using two different diameters (0.5 cm and 1cm). Also, three volumetric percentages of rings addition (3%, 6% and 10%) were tested for each diameter. The discharging process was done with

A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.

Designing women clothes is one of the application arts has rules and fundamentals and also laws connected the individual , and it is the whole thought and the decorative element for the cloth, in this way it highlighted the aesthetic and functional aspects which achieving the basic objective of existing the design, and the design has motives of designer chisel of the ability to deduct and device new systems and relations of his self sense of the components from which one could sustain the designing thought.Besides, the cultural and philosophy level to him which considered elements and motives , the researcher depending on them in designing women clothes, and the research problem is limited on the imposing the following question: Could th

يُعد موضوع الذكاء الاصطناعي اليوم أحد أبرز القضايا التي تشغل الباحثين في التكنولوجيا العالية والدقيقة ، وكذلك في باقي الحقول الأخرى نظراًّ لربطها بالمنتجات والخدمات البشرية من أجل تقديم عدة مساهمات الغرض منها تبسيط وتسهيل الحياة الانسانية في مختلف المجالات في حالة إذا ما تم استخدامها وفق نهج أخلاقي مستدام يتضمن مجموعة من المبادئ كالعدالة والموضوعية والشفافية والمساءلة والمساواة ، وهي مبادئ تهدف بشكل عام

The research concern about the conceptual framework of crisis in the strategic view has become to mean opportunity to change not threat only. The research explains the multi stages of crisis & its characteristics that are difference from catastrophe and disaster. We rely on two criteria of classification of crisis (predictability & influence possibilities). Also there are sub crises with the main crisis; the important one is the Maida Crisis which is related with the informational dimension & the Psychological Crisis which is related with the Human dimension or the victim management. The current research aimed to develop crises management strategy according to Islamic perspective based on model of ( Augustine, 1995).&

The Frequency-hopping Spread Spectrum (FHSS) systems and techniques are using in military and civilianradar recently and in the communication system for securing the information on wireless communications link channels, for example in the Wi-Fi 8.02.X IEEE using multiple number bandwidth and frequencies in the wireless channel in order to hopping on them for increasing the security level during the broadcast, but nowadays FHSS problem, which is, any Smart Software Defined Radio (S-SDR) can easily detect a wireless signal at the transmitter and the receiver for the hopping sequence in both of these, then duplicate this sequence in order to hack the signal on both transmitter and receiver messages using the order of the se