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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Communication Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Capacity,Relay channel,Polar code,Channel polarization,Relay channel polarization,Good index of relay channel
- چکیده:
- چکیده انگلیسی: Polar codes, that have been recently introduced by Arikan, are one of the first codes that achieved the capacity for vast numerous channels and they also have low complexity in symmetric memoryless channels. Polar codes are constructed based on a phenomenon called channel polarization. This paper discusses relay channel polarization in order to achieve the capacity and show that if inputs of two different relay channels follow the Arikan polarization structure, then they will be categorized as good and bad relay channels. Also, it has been shown that the eencoding and decoding complexity for these codes is , and their error probability is like the Arikan's work. In order to validate our construction of polar codes for relay channels, some numerical examples for this idea have been presented. Also, the efficiency of this construction for decode-and-forward and compress-and-forward relaying strategies have been analyzed by using simulation results for finite block length in relay channels with orthogonal receiver.
- انتشار مقاله: 18-08-1395
- نویسندگان: Hassan Tavakoli,Saied Pakravan
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Amygdala,coping strategies,Stress,Cortisol,Epinephrine,Rhesus macaque
- چکیده:
- چکیده انگلیسی: Objective(s): In the present study the effect of stress on monkeys that had learned to retrieve food from a five-chamber receptacle, as well as the relationship between their behavior and the serum cortisol and epinephrine levels and relative size of the amygdala was evaluated.
Materials and Methods: Six male rhesus monkeys were individually given access to the food reward orderly. They could easily retrieve the rewards from all chambers except for the chamber 4, which a brief, mild electric shock (3 V) was delivered to them upon touching the chamber’s interior. The coping behaviors were video-recorded and analyzed offline. Baseline serum cortisol and epinephrine levels were measured before the experiments using monkey enzyme-linked immunosorbent assay kit. One week after the behavioral experiment, the monkeys’ brains were scanned using magnetic resonance imaging under general anesthesia. The cross-sectional area of the left amygdala in sagittal plane relative to the area of the whole brain in the same slice was evaluated by the planimetric method using ImageJ software.
Results: Exposure to the distressing condition caused different behavioral responses. Monkeys with higher baseline levels of serum cortisol and epinephrine and larger amygdala behaved more violently in the face of stress, indicating adopting emotion-focused stress-coping strategies. Conversely, those with low plasma epinephrine, moderate cortisol, and smaller amygdala showed perseverative behavior, indicating a problem-focused coping style.
Conclusion: In dealing with the same stress, different responses might be observed from nonhuman primates according to their cortisol and epinephrine levels as well as their amygdala dimensions.- انتشار مقاله: 14-05-1396
- نویسندگان: Elaheh Tekieh,Esmail Riahi,Masoomeh Kazemi,Hedayat Sahraei,Hassan Tavakoli,Hamed Aliyary,Mostafa Hajinasrollah,Maryam Salehi,Gholamhossein Meftahi,Mehdi Saberi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Copper chromite,Nano particle,Inverse co-precipitation
- چکیده:
- چکیده انگلیسی: In this study, copper chromite (CuCr2O4) nanoparticles was prepared by inverse co-precipitation method. In this method, cupric nitrate trihydrate, (Cu (NO3)2.3H2O) and chromium nitrate nonahydrate, (Cr (NO3) 3.9H2O) with a mole ratio of 1:2 were used. Characterization of CuCr2O4 nanoparticles was performed by Fourier Transform Infrared Spectroscopy (FT-IR), Raman Spectroscopy, X-ray Diffraction Spectroscopy (XRD), Thermo-Gravimetric/Differential Scanning Calorimetry (TG-DSC), and Field Emission Scanning Electron Microscopy (FE-SEM). The results show that CuCr2O4 crystal can be obtained at temperature 520 °C. Also, phase structure of the CuCr2O4 depends on both Cu:Cr molar ratio and temperature in the starting reactants. Based on this method and under optimum conditions, the temperature for calcination (520 oC), the crystallite size of nanoparticles (18 nm), the spherical structure particles (30 to 70 nm) were obtained.
- انتشار مقاله: 20-06-1393
- نویسندگان: Hassan Tavakoli,Rasoul Sarraf Mamoory,Ali Reza Zarei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: FT-IR,Pharmaceutical formulation,Simultaneous determination,Quantitative analysis,Hydrochlorothiazide,Enalapril maleate
- چکیده:
- چکیده انگلیسی: A new Fourier Transform-Infra Red (FT-IR) spectrometric method was developed for assaying hydrochlorothiazide (HCT) and enalapril maleate (ENM) in binary solid pharmaceutical formulations. Multivariate Partial Least Squares (PLS) method was used for calibration of derivative spectral data. Acetonitrile was used as solvent due to its spectral transparency and adequate solubility of analytes in it. A 4- levels full factorial design of binary standard solutions of HCT and ENM were prepared and used for calibration in the spectral range of 1550-1800 cm-1. Statistical parameters such as correlation coefficient(R), Standard Error of Estimation (SEE), Standard Error of Prediction (SEP), and Standard Error of Cross Validation (SECV) have been evaluated and used for selecting of optimizing of parameters. Correlation coefficients were 0.9990 and 0.9995 and Relative Standard Deviation (RSD) were 1.97% and 1.35% (n=5) for HCT and ENM, respectively. Detection limits of ENM and HCT were obtained 0.54 and 0.99 mg/mL respectively. The proposed methods were successfully applied to the determination of the over mentioned drugs in laboratory-prepared mixtures and in commercial tablets. This method has suitable accuracy, precision, repeatability and is comparable with reference standard methods.
- انتشار مقاله: 23-09-1392
- نویسندگان: Seyyed Hamid Ahmadi,Hassan Tavakoli,Majid Amirzadeh,Mohammad Reza Sangi
- مشاهده