We address the throughput maximization problem for downlink transmission in DF-RELAY-assisted cognitive radio networks (CRNs) based on simultaneous wireless information and power transfer (SWIPT) capability. In this envisioned network, multiple-input multiple-output (MIMO) RELAY and secondary user (SU) equipment are designed to handle both radio frequency (RF) signal energy harvesting and SWIPT functional tasks. Additionally, the cognitive base station (CBS) communicates with the SU only via the MIMO RELAY. Based on the considered network model, several combined constraints of the main problem complicate the solution. Therefore, in this paper, we apply heuristic guidelines within the convex optimization framework to handle this complexity. First, consider the problem of maximizing throughput on both sides of the RELAY separately. Second, each side progresses to solve the complex problem optimally by adopting strategies for solving sub-problems. Finally, these optimal solutions are synthesized by proposing a heuristic iterative power allocation algorithm that satisfies the combinatorial constraints with short convergence times. The performance of the optimal proposed algorithm (OPA) is evaluated against benchmark algorithms via numerical results on optimality, convergence time, constraints’ compliance, and imperfect channel state information (CSI) on the CBS-PU link.

In this study, we introduce a new two-way RELAY channel and obtain an inner bound and an outer bound for the discrete and memoryless multiple access RELAY channels with receiver-source feedback via two-way RELAY channel in which end nodes exchange signals by a RELAY node. And we extend these results to the Gaussian case. By numerical computing, we show that our inner bound is the same with one obtained by Hou-Koetter-Kramer, for the channel with RELAY-source feedback.

Minimization of the discrimination time between the backup and main overcurrent RELAY is one of the most critical issue in RELAY coordination of power system. Determination of time setting multipliers (TSMs) using evolutionary algorithms has been studied in previous papers. In this paper, TSM, various characteristics of the overcurrent RELAYs and pickup currents are simultaneously considered to improve coordination of main and backup overcurrent RELAYs. Furthermore, the coordination problem can also be considered as an optimization problem which can be solved using artificial intelligent methods. Recently, a novel optimization algorithm, called hyper-sphere search (HSS) algorithm, has been introduced. In this paper, Improved HSS (IHSS) is introduced. Based on the problems mentioned in this paper, the IHSS algorithm is more appropriate for obtaining the characteristics of the overcurrent RELAYs, pickup currents and their TSMs. The result of IHSS is compared with HSS algorithm which has been used in previous studies. The simulation results on the test network show the efficiency of using IHSS and considering pickup currents in term of better RELAYs coordination.

Introduction: Colorectal Carcinoma is a main health problem in many countries and the third common cancer in Iran. This malignancy at present is the most curable carcinoma of gastrointestinal tract. Variation in the expression of the proteins produced by P53, P21, P16, E-cadherin, and β-catenin genes have been noted in this malignancy and may be important in the prognosis and therapeutic response rate. The aim of this study was to compare the frequency and pattern of expression of these proteins in tumoral and nontumoral colonic mucosa. The correlation with prognostic factors including tumor stage, grade, and vascular and perineural invasion was also determined. Material and Methods: The paraffin blocks from tumoral and nontumoral parts of the colon obtained from 58 patients with colorectal adenocarcinoma were studied along with 50 colectomic cases in individuals without malignancy. Cylindrical tissue fragments were obtained from appropriate parts of donor blocks by using a 2.5 mm punch biopsy instrument. Each 30 samples were manually ARRAYed in one tissue ARRAY block. Expression of above genes was investigated after sectioning the blocks and immunohistochemical staining of slides. Results: The expression of P53 in tumor cells was significantly more common than in colonic nontumor cells and colon of individuals without tumor (p<0.001); expression of this protein in tumoral tissues was directly related to vascular invasion (p=0.017). The expression frequency of P21 and P16 in tumor cells was less than nontumoral tissues of patients with cancer and patients without cancer (p<0.001). These two gene products showed no correlation with prognostic factors. The expression frequency of membranous E-cadherin and β-catenin in tumor cells was not different from controls, while the membranous expression of E-cadherin was inversely related to cell differentiation (p=0.023) and vascular invasion (p=0.025). In addition, the membranous expression of β-catenin was inversely related to vascular invasion (p=0.049). Cytoplasmic and nuclear expression of β-catenin in tumor cells were significantly higher than their expression in the controls (p<0.001). Cytoplasmic expression of this marker was inversely related to disease stage (p=0.013), while its nuclear expression was inversely related to cell differentiation (p=0.012).Conclusion: According to our data, it seems that we are able to predict aggressive capacity of the colorectal tumor by determining the frequency and pattern of expression of P53, E-cadherin and β-catenin proteins. These studies can be done simply on formalin-fixed small biopsy samples before surgery to provide valuable information for surgeons, gastroenterologists, and oncologists to choose the best therapeutic approach and predict the therapeutic response. Manual tissue ARRAY method is believed to be an economical technique for similar research projects.

MUSIC (Multiple Signal Classification) algorithm as a base of Sub-Space algorithms is applied in ARRAY processing systems. The error of the algorithm in detection & resolution depends on several parameters, such as snapshots, signal-to-noise ratio and sensor locations. In this paper, the previous dependency is investigated. So, all the scenarios of ARRAY shapes are defended and then i analytic formulas are derived in two bearings of θ and φ We will show which parameters have ithe most effect on the desired error (the error threshold).

The In-Band Full-Duplex (IBFD) technique is attracting a great deal of attention thanks to its ability to simultaneously transmit and receive the information over the same frequency band. IBFD has the potential to double the spectral efficiency and system capacity, compared to conventional Half-Duplex (HD) schemes. However, strong self-interference caused by simultaneous transmission and receiption over the same frequency band, renders the feasibility of IBFD in practice. Recently, advanced self-interference cancellation techniques are proposed to address this issue. In this paper, an IBFD RELAY network with Simultaneous Wireless Information and Power Transmission (SWIPT) is introduced that applies multiple RELAYs. We propose a joint antenna-and-RELAY selection scheme that decreases the complexity and increases the ergodic capacity. We provide simulation results for the outage probability and the ergodic capacity. The results show that the IBFD system outperforms the HD system, for a certain range of self-interference power.

Spatial diversity is one of the most effective techniques to combat fading in wireless channels that can be implemented through antenna ARRAYs. In this paper the hybrid decode-amplify-forward protocol with best RELAY selection (HDAF-S)in a cooperative system with multiple parallel RELAYs with independent non-identically channels is considered and tight upper and lower bounds on bit error rate (BER) of this protocol is derived. It is shown that the BER of this protocol outperforms the BER of amplify and forward (AF) protocol but cannot exceeds the performance of decode and forward (DF) protocol. Then through asymptotic analysis for high SNR regime, it is shown that the HDAF-S protocol achieves full diversity order. Then the BER performance of HDAF protocol with n-th best RELAY selection (HDAF-nS) in independent and identically distributed channels is analyzed and tight upper and lower bounds on the BER are derived. Asymptotic analysis shows that this protocol cannot achieve full diversity order and it is shown that the diversity order decreases as n increases. The analytical results are validated through simulations.

The Polar coding is a method which have been proposed by Arikan and it is one of the first codes that achieve the capacity for vast numerous channels. This paper discusses RELAY channel polarization in order to achieve the capacity and it has been shown that polarization of two RELAY channels can be given a more achievable rate region in the general form. This method is compatible with the original vision of polarization based on the combining, splitting and polarizing of channels and it has been shown that the complexity of encoding and decoding for these codes in mentioned method are O(N log N), and also error probability for them is O(2-(N)b). Choose the best sub-channels in polarized RELAY channels for sending data is a big trouble in this structure. In this paper, we have been presented a new scheme for choosing a good index for sending the information bits in RELAY channels polarized in order to have the best performance by using sending information bits over FIF sets.

The present study on politeness is an attempt to examine (dis)agreeing strategies utilized by EFL learners while chatting on the internet. Subjects of the study were forty male and thirty-three female Iranian natives whose internet RELAY chat (IRC) interactions, composed of 400 excerpts, were collected between December 2007 and September 2008. Data analysis was based on the general taxonomy of politeness strategies suggested by Brown and Levinson (1987) which is the baseline of many politeness studies today. The results indicate that IRC is a mode of communication whose characteristics are typically different from face-to-face and real-life conversational settings. Some common face threatening acts (FTAs) like ‘direct disagreements’ are performed widely in chat channels. Furthermore, gender-oriented differences were found not to be statistically significant on the internet.