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In this letter, we propose a trellis-coded non-orthogonal multiple access (NOMA) scheme. The signals for different users are produced by trellis coded modulation (TCM) and then superimposed on different power levels. By interpreting the encoding process via the tensor product of trellises, we introduce a joint detection method based on the Viterbi algorithm. Then, we determine the optimal power allocation between the two users by maximizing the free distance of the tensor product trellis. Finally, we manifest that the trellis-coded NOMA outperforms the uncoded NOMA at high signal-to-noise ratio (SNR).

Recent studies have demonstrated the superiority of non-orthogonal multiple access (NOMA) over orthogonal multiple access (OMA) in cooperative communication networks. In this paper, we propose a novel half-duplex cooperative asynchronous NOMA (C-ANOMA) framework with user relaying, where a timing mismatch is intentionally added in the broadcast signal. We derive the expressions for the throughputs of the strong user (acts as relay) which employs the block-wise successive interference cancellation (SIC) and the weak user which combines the symbol-asynchronous signal with the interference-free signal. We analytically prove that in the C-ANOMA systems with a sufficiently large block length, the strong user attains the same throughput to decode its own message while both users can achieve a higher throughput to decode the weak user's message compared with those in the cooperative NOMA (C-NOMA) systems. Besides, we obtain the optimal timing mismatch when the block length goes to infinity. Furthermore, to exploit the trade-off between the power consumption of the base station and that of the relay user, we solve a weighted sum power minimization problem under quality of services (QoS) constraints. Numerical results show that the C-ANOMA system can consume less power compared with the C-NOMA system to satisfy the same QoS requirements.

In this letter, we investigate the possible benefits of asynchrony in the frequency domain for the non-orthogonal multiple access (NOMA) schemes. Despite the common perspective that asynchrony in transmission or reception of multi-stream signals is harmful, we demonstrate the advantages of adding intentional frequency offset to the conventional power domain-NOMA (P-NOMA). We introduce two methods which add artificial frequency offsets between different sets of sub-carriers destined for different users. The first one uses the same successive interference cancellation (SIC) method as the conventional P-NOMA except that it enjoys reduced inter-user interference (IUI) between interfering sub-carriers. The second scheme adopts a precoding at the base station and a linear preprocessing scheme at the receiving user. It decomposes the broadcast channel into parallel channels circumventing the need for SIC. As a result, it fully exploits the advantages provided by the frequency asynchrony and enables the interference-free transmission to the users. The numerical results show that both methods can outperform the conventional P-NOMA.

There has been extensive research on large scale multi-user multiple-input multiple-output (MU-MIMO) systems recently. However, there are many obstacles to achieve full potential of using large number of receive antennas. One of the main issues, which will be investigated thoroughly in this paper, is timing asynchrony among signals of different users. Most of the works in the literature, assume that received signals are perfectly aligned which is not practical. We develop a mathematical model that explicitly accounts for the timing mismatch among the received signals and shows the detrimental impact of asynchrony on the MRC receiver.

Background: In the modern age, with its increasing reflexivity, death has changed to technical issue, its quality is left to the medical profession, so a new definition of death is introduced as brain death and the possibility of organ transplantation. Therefore, this article aimed to investigate death attitudes and its relationship with organ donation. Materials and Methods: This descriptive-analytical study examined 475 people over the age of 20 years in Kashan in September 2017 using a population-based random sampling method. The research instrument was a researcher-made questionnaire based on Giddens' theory of late modernity. Data analysis is based on correlation and structural equation design using SPSS and AMOS software. Results: Among the five dimensions of belief to death, natural belief, with the acceptance of death as the end of life and an inevitable reality as a result of rethinking, awareness of death, medical advances and confidence in experts of the field among the five dimensions of belief to death, had the highest average (3.77 out of 5) and were the most important explanatory variables for both religious (β=0.35, P

In this note we show that a connected, simply connected nilpotent Lie group with an integrable left-invariant complex structure on a generating and suitably complemented subbundle of the tangent bundle admits a Cauchy-Riemann (CR) embedding in complex space defined by polynomials. We also show that a similar conclusion holds on suitable quotients of nilpotent Lie groups. Our results extend the CR embeddings constructed by Naruki [Publ. Res. Inst. Math. Sci. 6 (1970), pp. 113–187] in 1970. In particular, our generalisation to quotients allows us to see a class of Levi degenerate CR manifolds as quotients of nilpotent Lie groups. [ABSTRACT FROM AUTHOR]

In this work, we regard f(R, T) gravity as an effective description of the acceleration of the universe and reconstruct the functionf(R, T) from the holographic Ricci dark energy by considering a Bianchi type I universe. So the connection gives us an opportunity to redefine the Hubble parameter, the pressure, the equations of state parameter, and the energy density parameter representation by considering Bianchi type I models for holographic Ricci dark energy. We wrap up the evolution of the accelerated expansion of the anisotropic universe, which is faster than the evolution of the FRW and ACDM models. Key words: anisotropic universe, modified gravity, holographic Ricci dark energy, Hubble parameter, Bianchi type I. Nous considerons ici la gravitef(T, R) comme une description efficace pour l'acceleration de l'univers et reconstruisons la fonction f(T, R) a partir de l'energie sombre holographique de Ricci en considerant un univers de type I de Bianchi. Cette connexion nous donne alors une opportunite pour redefinir le parametre de Hubble, la pression, l'equation du parametre d'etat et la representation du parametre de densite d'energie en considerant des modeles de type I de Bianchi pour l'energie sombre holographique de Ricci. Nous concluons avec une evolution de l'expansion acceleree de l'univers anisotrope qui est plus rapide que l'evolution des modeles FRW et ECMD. [Traduit par la Redaction] Mots-cles : univers anisotrope, gravite modifiee, energie sombre holographique de Ricci, parametre de Hubble, type I de Bianchi., 1. Introduction Type Ia supernovae observational data show that the universe is dominated by two dark components: dark matter (DM) and dark energy (DE) [1, 2]. DM, matter without pressure, [...]

A new distribution, the Weibull-Rayleigh distribution, is introduced, and various properties of the distribution are provided. Two real data sets are used to illustrate the applicability of the Weibull-Rayleigh distribution., 1. Introduction The Weibull distribution has been widely used in lifetime studying, reliability, and fitting a best model to data. To add flexibility to the Weibull distribution, various generalizations of [...]

In this paper, we consider the generalized ghost dark energy in a Bianchi type-I metric (which is a spatially homogeneous and anisotropic) in the framework of Brans-Dicke theory. For this purpose, we use the squared sound speed [v.sup.2.sub.s] the sign of which determines the stability of the model. At first, we obtain the equation of state parameter, [ω.sub.Λ] = [[p.sub.Λ/[ρ.sub.Λ, the deceleration parameter q and the evolution equation of the generalized ghost dark energy. We find that, in this case, [ω.sub.Λ] cannot cross the phantom line ([ω.sub.Λ] > -1) and eventually the universe approaches a de-Sitter phase of expansion ([ω.sub.Λ] [right arrow] -1). Then, we extend our study to the case of generalized ghost dark energy in a non-isotropic and Brans-Dicke framework and find out that the transition of [ω.sub.Λ] to the phantom regime can be more easily accounted for than when it is restored into the Einstein field equations. In conclusion, we find evidence that the generalized ghost dark energy in BD theory can lead to a stable universe favored by observations at the present time. Key words: anisotropic universe, generalized ghost dark energy, Brans-Dicke theory, Bianchi type I, phantom phase. Nous etudions ici l'energie sombre fantome generalisee (CGDE) dans une metrique de type I de Bianchi (qui est spatialement homogene et anisotrope) dans le cadre de la theorie de Brans-Dicke. A cette fin nous utilisons le carre de la vitesse du son [v.sup.2.sub.s] dont le signe determine la stabilite du modele. Nous obtenons d'abord l'equation d'evolution du parametre d'etat [ω.sub.Λ] = [p.sub.Λ]/[ρ.sub.Λ], le parametre de deceleration q et l'equation d'evolution de l'energie sombre fantome generalisee. Nous trouvons ici que [ω.sub.Λ] ne peut traverser la ligne du fantome([ω.sub.Λ] > -1) et eventuellement, l'univers approche une phase d'expansion de de-Sitter ([ω.sub.Λ] → -1). Nous etendons alors notre etude au cas de l'energie sombre fantome generalisee a un cadre de Brans-Dicke non isotrope et trouvons que la transition de [ω.sub.Λ] au regime fantome peut se faire plus facilement lorsque inseree dans l'equation de champ d'Einstein. En conclusion, nos resultats indiquent que l'energie sombre fantome generalisee peut mener a un univers stable, en accord avec les observations actuelles. [Traduit par la Redaction] Mots-cles: univers anisotrope, energie sombre fantome generalisee, theorie de Brans-Dicke, Bianchi de type I, phase fantome. PACS Nos.: 95.36.+X, 95.35.+d, 98.80.-k., 1. Introduction Accelerating expansion of the universe [1, 2] can be explained either by a missing energy component usually called 'dark energy' (DE) with an exotic equation of state (EoS), [...]

"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: During recent three decades, parallel to the improvement of arthroscopic techniques, intra-articular block by direct injection of anesthetics into the joint has been used in knee arthroscopy. In this study the efficacy of intra- articular block by complex of bupivacaine, lidocaine and adrenaline in knee arthroscopy has been assessed. "n"nMethods: Forty one healthy adults (age range: 18-55 years) with knee problems selected for diagnostic arthroscopy. Anesthesia was induced by direct injection of 10ml 2% bupivacaine, 10ml 0.5% lidocaine plus 1/100000 adrenaline into the knee joint. Duration of operation and volume of serum used for irrigation during the procedure; pain and analgesics requirement, during and after arthroscopy; VAS (Visual Analogue Scale) score, at time of discharge from recovery and also patient's and surgeon's satisfaction were assessed. "n"n Results: Sixty eight percent and 29% of cases reported mild and moderate degree of pain perception during arthroscopy, respectively, and only one case for which general anesthesia was performed, reported severe pain. VAS mean was 2.78. Seventy eight percent of cases and the surgeon in 80% of procedures had excellent or good satisfaction with intra-articular block."n"nConclusions: Considering high level of satisfaction in both patients and surgeon and mean of VAS, complications of other modalities of anesthesisa and simplicity of the technique, intra-articular block can be used as an easy, safe and efficient method for knee arthroscopy.

Background: Skin lesions - benign and malignant - occur frequently in organ transplant recipients receiving long-term immunosuppressive therapy. These patients are at greater risk of skin cancers. Aims: To study dermatologic problems in renal transplant recipients (RTRs). Methods: One hundred patients (53 men and 47 women) were consecutively examined for benign and malignant skin complications since transplantation in Razi Hospital in Tehran Medical University. The main immunosuppressive therapy regimen in these patients was a combination of prednisolone, azathioprine, and cyclosporine. Results: The early and most common complication was cosmetic side effects that occurred in 98% patients. Skin infections occurred in 83% of the patients and most of them were viral infections (65%), especially of human papilloma viruses (HPVs) in 40% of the patients. We found six cases of malignancy in these patients in that four cases were skin cancers, including one case of SCC, one BCC, and two cases of Kaposi′s sarcoma. Dermatologic problems occur most frequently in RTRs, especially skin cancers which have higher frequency in these patients than general population, particularly, Kaposi sarcoma. Sun exposure has an important role in developing epithelial skin cancers following transplantation. The age of developing skin cancer in these patients was early than normal population. Conclusion: Our results emphasize the importance of dermatologic examinations and monitoring RTRs to obtain an early diagnosis and treatment of cutaneous manifestations.

"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Infertility influences various aspects of a woman's personality and psyche, and affects her functions within her family and occupation, as well as her ability to communicate. Studies have shown that infertility is associated with depression, stress, anxiety, dissatisfaction with life and other psychological problems. The purpose of the present study was to compare the dimensions of neuroticism and androgyny in fertile, infertile and postmenopausal women."n"n Methods: This study included of 180 fertile, infertile and postmenopausal women (60 in each group) selected from inpatients at Imam Khomeini and Mirza Koochak Khan Hospitals, Tehran, Iran, during 2004. Data were collected using the NEO Personality Inventory Neuroticism Scale and Bem Sex-Role Inventory and analyzed using the one-way ANOVA technique."n"n Results: LSD test results show that mean neuroticism scores were significantly different between the three groups, with scores following the trend: infertile women > postmenopausal women > fertile women. The mean androgyny scores were also significantly different between the three groups, following the trend: infertile women < postmenopausal women < fertile women (p