Improving NOMA Multi-Carrier Systems with Intentional Frequency Offsets

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

Trellis-Coded Non-Orthogonal Multiple Access

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)

The Impact of ethical leadership on job stress and occupation turnover intention in nurses of hospitals affiliated to Shahrekord University of Medical Sciences

زمینه و هدف: رهبری اخلاقی، زمینه تعهد و وفاداری کارکنان را فراهم می سازد و زمانی که کارکنان به رهبرانشان اعتماد داشته باشند، استرس کاری در میان آنان کاهش یافته و تصمیم جدی مبنی بر ترک خدمت نخواهند داشت. این پژوهش با هدف درک آثار رهبری اخلاقی بر قصد ترک خدمت پرستاران و بررسی میزان استرس کاری به عنوان یک متغیر میانجی در میان رهبری اخلاقی و قصد ترک خدمت آنان صورت گرفته است. روش بررسی: در این مطالعه توصیفی- همبستگی، تعداد 180 نفر از پرستاران شاغل در بیمارستان های دانشگاه علوم پزشکی شهرکرد به صورت تصادفی طبقه ای متناسب با حجم جامعه انتخاب شدند. ابزار گردآوری داده ها شامل پرسشنامه استاندارد رهبری اخلاقی، استرس کاری و قصد ترک خدمت بود. یافته ها: نتایج پژوهش نشان داد که بین رهبری اخلاقی و قصد ترک خدمت رابطه منفی و معنی دار و بین استرس کاری و قصد ترک خدمت رابطه مثبت و معنی داری وجود دارد (به ترتیب 0/58- =β= 0/66 ،β و 0/05>P)؛ همچنین بین رهبری اخلاقی و استرس کاری رابطه منفی و معنی داری مشاهده شد (0/05> P و 29/0- =β). نتیجه گیری: رهبری اخلاقی می تواند باعث کاهش استرس کاری پرستاران و در نتیجه کاهش قصد ترک خدمت آن ها شود؛ لذا مدیران می توانند با گسترش فرهنگ ارزش های اخلاقی و کاهش عوامل استرس زای شغلی باعث افزایش اعتماد، وفاداری و تعهد سازمانی پرستاران و در نتیجه کاهش ترک خدمت آن ها گردند

Ferrofluid convective heat transfer under the influence of external magnetic source

AbstractFerrofluid convective heat transfer in a cavity with sinusoidal cold wall is examined under the influence of external magnetic source. The working fluid is Fe3O4-water nanofluid. Single phase model is used to estimate the behavior of nanofluid. Vorticity stream function formulation is utilized to eliminate pressure gradient source terms. New numerical method is chosen namely Control volume base finite element method. Influences of Rayleigh, Hartmann numbers, amplitude of the sinusoidal wall and volume fraction of Fe3O4 on hydrothermal characteristics are presented. Results indicate that temperature gradient enhances as space between cold and hot walls reduces at low buoyancy force. Lorentz forces cause the nanofluid velocity to reduce and augment the thermal boundary layer thickness. Nusselt number augments with rise of buoyancy forces but it decreases with augment of Lorentz forces

Application of He's variational iteration method to nonlinear Jaulent–Miodek equations and comparing it with ADM

AbstractInstead of finding a small parameter for solving nonlinear problems through perturbation method, a new analytical method called He's variational iteration method (VIM) is introduced to be applied to solve nonlinear Jaulent–Miodek, coupled KdV and coupled MKdV equations in this article. In this method, general Lagrange multipliers are introduced to construct correction functionals for the problems. The multipliers can be identified optimally via the variational theory. The results are compared with exact solutions

The Impact of Education, Based on the BASNEF Model, on Maternal Attitudes toward Child Abuse in Shahrekord Health Centers, 2012

Background As childhood is considered to be the infrastructure for growth and progress, experiencing misconduct may leave behind a heritage of imbalance and unrest which may be manifested in any situation in some form of mental disorder (neurotic attack). This problem leads to physical and mental disorder in children and inflicts heavy social and economic damages to the society. This research aims at evaluating the impact of education, based on BASNEF model, on maternal attitude towards child abuse. Methods The current research is based on an interventional study on 95 mothers referred to the Shahrekord health center. They were randomly selected and divided into two groups of test and control, and education was conducted in four sessions based on structures of BASNEF model. Finally their obtained information was analyzed using paired t-test, independent t-test, Mann-Whitney and Chi-square statistical tests. Results The mean score in beliefs was 77.73±7.27, attitudes 87.01±8.1, subjective norms 85.55±8.4 and enabling factors 82.77±10.64 in the test group. There was a significant difference in the average marks of the structures of the BASNEF model (beliefs, attitudes, subjective norms, and enabling factors) between the control and intervention groups after the training process Conclusion Model-based training has a positive effect on improving attitudes; therefore, instead of traditional methods, applying a planned training program is suggested so that its effects can be reliable

The impact of information technology on organizations maturity of public and non-public hospitals in Isfahan

زمینه و هدف: یکی از مهمترین حوزه های کاربرد فناوری اطلاعات حوزه بهداشت و درمان می باشد. مطالعات نشان می دهند که فناوری اطلاعات می تواند اثرات شگرفی بر بلوغ بیمارستان ها داشته باشد. در این پژوهش سعی شده است به تاثیر فعالیت های فناوری اطلاعات بر سطوح بلوغ بیمارستان های دولتی و غیردولتی شهر اصفهان پرداخته شود. روش بررسی: این پژوهش به روش توصیفی تحلیلی در سال 1393 انجام گردید. جامعه پژوهش شامل مسئولان و کارشناسان فناوری اطلاعات بیمارستانهای دولتی وغیر دولتی شهر اصفهان به تعداد 164 نفر بود. ابزارگردآوری اطلاعات در این مطالعه پرسشنامه سنجش فعالیت های فناوری اطلاعات و سنجش بلوغ سازمانی شامل مولفه های نوآوری، بهبود دادن و پشتیبانی بود که روایی و پایایی آن تایید گردید. داده ها توسط نرم افزار های17 spss و لیزرل با استفاده از شاخص های آماری توصیفی و آزمون های فریدمن ، مدلسازی معادلات ساختاری و رگرسیون مورد تجزیه و تحلیل قرار گرفتند. یافته ها: میانگین و انحراف معیار متغیر فناوری اطلاعات66/0 ± 21/3 و مولفه های بلوغ سازمانی شامل نوآوری78/0 ± 25/3 ، بهبود دادن67/0 ± 48/3 و پشتیبانی66/0± 22/3 بود. نتایج این مطالعه نشان داد متغیر فن آوری اطلاعات به ترتیب بیشترین پیش بینی را برای متغیرهای پشتیبانی، بهبود دادن، نو آوری و بلوغ سازمانی داشت. نتیجه گیری: فعالیت های فناوری اطلاعات می تواند سازمان را به سمت سازمانی بلوغ یافته هدایت نموده و در پشتیبانی، نوآوری و بهبود سازمان نقش موثری را ایفا نماید. بنابراین به مدیران پیشنهاد می شود با اقداماتی نظیر استفاده از نیروی متخصص و دارای دانش فنی، در زمینه فناوری اطلاعات و سیستم های اطلاعاتی ،تشکیل کمیته راهبردی فناوری اطلاعات و ... تجدید نظر به عمل آورند

Mephrolithiasis as a common urinary system manifestation of inflammatory bowel diseases; a clinical review and meta-analysis

The extra-intestinal manifestations of inflammatory bowel disease (IBD) are common and involve other organs or systems for example; urinary system. Evidence Acquisitions: For this review, we used a variety of sources by searching through Web of Science, PubMed, EMBASE, Scopus and directory of open access journals (DOAJ). Results: Urinary complications may occur in up to 22% of patients and nephrolithiasis or renal/kidney stones have been suggested to be a common manifestation of disease in forms of uric acid, calcium phosphate or calcium oxalate. We performed a meta-analysis on five clinical trials and reported that correlation between IBD and formation of stone in renal system is positive and significant (Fix-effect model; CI: 95%, P <0.001, and random-effect model; CI: 95%, P = 0.03). Conclusions: Based on the reports of the clinical trials, calcium oxalate is more prevalent in Crohn’s disease (CD) than in ulcerative colitis (UC)

Protective effects of forced exercise against nicotine-induced anxiety, depression and cognition impairment in rat

Nicotine is one of the psychostimulant agents displaying parasympathomimetic activity; the chronic neurochemical and behavioral effects of nicotine remain unclear. Exercise lowers stress and anxiety and can act as a non-pharmacologic neuroprotective agent. In this study, the protective effects of exercise in nicotine withdrawal syndrome-induced anxiety, depression, and cognition impairment wereinvestigated. Methods: Seventy adult male rats were divided randomly into five groups. Group 1 served as negative control and received normal saline (0.2 mL/rat, i.p.) for 30 days, whereas group 2 (as positive control) received nicotine (6 mg/kg/day, s.c.) for the first 15 days. Groups 4, 5, and 6 were treated with nicotine (6 mg/kg/day, s.c.) for the first 15 days and then were treated with forced exercise, bupropion (20 mg/kg/day, i.p.), or a combination of the two for the following 15 days. Between day 25 and day 30, Morris water maze was used to evaluate spatial learning and memory. From days 31 to 35, the elevated plus maze (EPM), open field test (OFT), forced swim test (FST), and tail suspension test (TST) were used to investigate the level of anxiety and depression in the subjects. Results: Nicotine-dependent animals indicated a reflective depression and anxiety in a dose-dependent manner in FST, EPM, and TST, which were significantly different from the control group and also can significantly attenuate the motor activity and anxiety in OFT. Conclusions: Forced exercise, bupropion, or their combination can attenuate nicotine cessation-induced anxiety, depression, and motor activity in the mentioned behavioral assay. We conclude that forced exercise can protect the brain against nicotine withdrawal-induced anxiety, depression, and cognitive alteration. © 2016 by De Gruyter

Achieving strategic growth in microenterprises through information technology: UK micro enterprise case study

Technology is a powerful tool that aims to assist efficient and effective use of resources within businesses. The paper examines to provide an understanding on the use of Information Technology tools and its influence on a UK microenterprise. It aims to explore further understanding on the strategic growth of any microenterprise firms. Through research findings and that of the analysis, it develops reasons and factors towards achieving greater time efficient practices with the use of information technology tools to achieve strategic growth for the business in the challenging economic markets. The paper presents the preliminary case study of UK microenterprise through observational findings examining general business processes, the challenges and drawbacks within the working environments and that of the use of technological tools. The findings of this case study will further enable the researchers to develop a novel framework to assist and enable any microenterprise in achieving overall strategic growth