Massive multiple-input multiple-output (MaMi) systems have attracted much research attention during the last few years. This is because MaMi systems are able to achieve a remarkable improvement in data rate and thus meet the immensely ongoing traffic demands required by the future wireless networks. To date, the downlink training sequence (DTS) for the frequency division duplex (FDD) MaMi communications systems have been designed based on the idealistic assumption of white noise environments. However, it is essential and more practical to consider the colored noise environments when designing an efficient DTS for channel estimation. To this end, this paper proposes a new DTS design by exploring the joint use of spatial channel and noise covariance matrices, when the channel is not reciprocal but the coherence block length remains limited. We derive an analytical solution for the mean square error (MSE) based on the proposed training design with colored noise. In addition, this paper exploits the method of random matrix theory to provide an analytical solution for the downlink (DL) achievable sum rate of the regularized zero forcing beamforming (RZFBF) precoder. Numerical results demonstrate that using the proposed DTS design, the MSE of the channel estimate is significantly reduced compared with the conventional training designs with white noise. Furthermore, the results show that the proposed pilot design markedly improves the DL achievable SR over the conventional training designs, especially at relatively low signal-to-noise-ratio (SNR) levels. This enables FDD MaMi systems to operate under more practical scenarios of colored noise and limited coherence time environments.
Forecasting has become common process and reality. Since man has found multiple forms of simple predictive predictions, fruitful predictive results have emerged, such as weather forecasting or trading on stock exchange. The research was organized by defining the problem, which was manifested by the question:
(What is the prediction in global logo design methods?)
The aim of the research: (revealing design prediction in the methods of global logos). The theoretical framework was: (the concept of prediction in the design of global logos), (methods of global logos), (types of prediction) and then were attached to indicators, results and conclusions, including:
- The color value of international logos came with human needs: a
Background: Optimal root canal retreatment was required safe and efficient removal of filling material from root canal. The aim of this in vitro study was to compare the efficacy of reciprocating and continuous motion of four retreatment systems in removal of root canal filling material. Materials and Methods: Forty distal roots of the mandibular first molars teeth were used in this study, these roots were embedded in cold clear acrylic,roots were instrumented using crown down technique and rotary ProTaper systemize Sx to size F2 ,instrumentation were done with copiousirrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilledwater, roots were obturated with AH26 sealer and Prota
... Show MoreIraqi EFL college instructors, who supervise the teaching practice of EFL student teachers, commonly experience the inefficient teaching performance of prospective teachers. This inefficiency is usually due to their inability to make connections between the practical experience and the theoretical knowledge of TEFL. One of the reasons behind this inability may be the employment of traditional ways of training and instructing student teachers. Moreover, it is usually noticed that many Iraqi EFL student teachers have a negative attitude toward the teaching profession. They explicitly state that they would join the teaching force only if they fail to work in any other field.
... Show MoreS Ali…, Journal of Physical Education, 2019 - Cited by 1
ملخص البحث: تناول البحث الحالي:(أنظمة التكوين الجمالي للكتابات والنصوص في النحت العربي المعاصر)، عددا من الأفكار الأساسية التي تمثل المادة النظرية لتفسير ظاهرة الكتابة في الفن بشكل عام وفي فن النحت بشكل خاص، ولكشف أنظمة التكوين الجمالي وأنواعها المتعددة من خلال فحص بعض النصوص البصرية للفنانين العرب المعاصرين، فقد جاء هذا البحث في أربعة فصول. خصص الفصل الأول: الإطار المنهجي للبحث لبيان مشكلة البحث، وأهم
... Show MoreThis paper presents an enhancement technique for tracking and regulating the blood glucose level for diabetic patients using an intelligent auto-tuning Proportional-Integral-Derivative PID controller. The proposed controller aims to generate the best insulin control action responsible for regulating the blood glucose level precisely, accurately, and quickly. The tuning control algorithm used the Dolphin Echolocation Optimization (DEO) algorithm for obtaining the near-optimal PID controller parameters with a proposed time domain specification performance index. The MATLAB simulation results for three different patients showed that the effectiveness and the robustness of the proposed control algorithm in terms of fast gene
... Show MoreA theoretical study has been proposed to investigate the effects of different laser radiations (Nd - glass, DF and C02) as a heating source on different glass samples (Optical glass, Bk - 7 and Soda - lime glass) and different waves lengths (10.6, 3.8, 1.6) ???. The heat changes as which are resulted due irradiation with laser sources have been determined by using the one dimension mathematical relation as a function of time (t) and depth (z). The results of the study show ed that the irradiation with C02 laser had a greater effect than DF laser, while the effects of Nd - glass laser were minimal with a power density of (1.8*10?? w/m2) within atime(l^sec).(Forboth Kinds) The change in the temperatures were not exceeded than (70"K) in all sa
... Show MoreThe aim of this study is to investigate the effect of environmental management accounting information (EMAI) on the design process of environmental and sustainable products of Iraqi industrial companies. This process has five different sub-processes: research process, analysis process, conceptual design process, detailed design process and design production process. The study uses the quantitative approach as the questionnaire was designed and distributed to 87 quality managers, production managers, design managers and financial managers. The MANOVA analysis shows that EMAI has a positive and significant effect on three of these processes, namely research process, analysis process and detailed design process, while EMAI has an insi
... Show MoreTheatrical costume constitutes a peculiarity in the theatrical performance because of its ability to communicate and communicate with the rest of the visual elements of the show in highlighting the intellectual and dramatic values. Fashion developments in theatrical performance, the second: the design elements of costumes and their characteristics, the third, which includes research procedures, and the fourth, in which the research results and conclusions were presented, including:
- The play (Happening on the Farm) is considered one of the plays with educational, educational and aesthetic goals, as it carried in its formats the features of simplicity and diversity of the visual formal connotations of the child.
- The c