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javad nourinia

  • Amir Bazdar, Amir Hatamian, Javad Ostadieh, Javad Nourinia, Changiz Ghobadi, Ehsan Mostafapour

    It has been a long time since we use magnetic resonance imaging (MRI) to detect brain diseases and many useful techniques have been developed for this task. However, there is still a potential for further improvement of classification of brain diseases in order to be sure of the results. In this research we presented, for the first time, a non-linear feature extraction method from the MRI sub-images that are obtained from the three levels of the two-dimensional Dual tree complex wavelet transform (2D DT-CWT) in order to classify multiple brain disease. After extracting the non-linear features from the sub-images, we used the spectral regression discriminant analysis (SRDA) algorithm to reduce the classifying features. Instead of using the deep neural networks that are computationally expensive, we proposed the Hybrid RBF network that uses the k-means and recursive least squares (RLS) algorithm simultaneously in its structure for classification. To evaluate the performance of RBF networks with hybrid learning algorithms, we classify nine brain diseases based on MRI processing using these networks, and compare the results with the previously presented classifiers including, supporting vector machines (SVM) and K-nearest neighbour (KNN). Comprehensive comparisons are made with the recently proposed cases by extracting various types and numbers of features. Our aim in this paper is to reduce the complexity and improve the classifying results with the hybrid RBF classifier and the results showed 100 percent classification accuracy in both the two class and the multiple classification of brain diseases in 8 and 10 classes. In this paper, we provided a low computational and precise method for brain MRI disease classification. the results show that the proposed method is not only accurate but also computationally reasonable.

    Keywords: Brain magnetic resonance imaging classification, feature reduction, k‑means algorithm, nonlinear features, radial basis function networks
  • Amir Hatamian *, Farzad Farshidi, Changiz Ghobadi, Javad Nourinia, Ehsan Mostafapour
    The increasing risk of cardiovascular diseases, stress, high blood pressure, obesity, sleep disorders, and depression causes electrocardiogram (ECG) monitors to be used for diagnosing health. The main objective of this research is to enhance the quality of the ECG signal using wavelet transform and adaptive filters. This research has been made as descriptive-analytic and the method is used in the signal processing stages to calculate the ECG modulation spectrum, the spectral-modulation filtering scheme, and the ECG database from the standard algorithm and performance criteria. The results of the simulation indicate that the conversion of Sym4 and the adaptive filter with the size of 0.0005 and the length of the filter of 25 signals to the noise will be greatly improved to reveal the main features of the ECG signal.
    Keywords: ECG Signal Quality, Wavelet, Adaptive Filter
  • Amir Hatamian, Changiz Ghobadi, Javad Nourinia, Ehsan Mostafapour *, Rahim Barzegari
    In this study, we present a comprehensive overview of the exact and approximate models and methods that are available to measure the dispersion of random rough surfaces. We investigated the structural implementation of such surfaces in the finite-difference time-domain (FDTD) simulation environment and introduced a method for error reduction in simulated environments with such surfaces to improve the accuracy of near-path scattering of random rough surfaces. For this aim, a new adsorbent consisting of two types of adsorbents with distinct properties is proposed. During different tests in environments with the random rough surfaces and more complex environments with abnormal dispersers, the superiority, and higher performance of the proposed adsorbents are verified and then, properties of the adsorbents are investigated. Next, two dimensional random rough surfaces are analyzed to investigate electromagnetic scattering. To determine the electromagnetic scattering field, surface height's and slope's joint probability density function is calculated and utilized after generating a two-dimensional rough surface. The ray-tracing base model is exploited, and then the Monte-Carlo technique is hired to convert an infinite integration form into the form of finite integration.
    Keywords: Absorbent layers, Random rough surface scattering, Finite-difference time-domain (FDTD) numerical method, Numerical methods in electromagnetism
  • Hosein Abdavinejad, Hadi Baghali, Javad Ostadieh, Ehsan Mostafapour *, Changiz Ghobadi, Javad Nourinia

    In this paper, we simulated a diffusion adaptive network in the underwater environment. The communication method between the nodes of this network is assumed to be the visible light communication technology (VLC) which in the underwater condition is known as the UVLC. The links between the nodes in this case are contaminated with the optical noise and turbulence. These contaminations are modeled with the proper statistical distributions depending on the underwater conditions. The optical turbulence modeling link coefficients are shown to be following the Log-normal distribution which its mean and variance are directly dependent on the temperature and the salinity of the simulated water and the assumed distance between the diffusion network nodes. The performance of the diffusion network in using UVLC technology is then analyzed both with simulations and theoretical calculations and the results are presented using the steady-state error metrics. Our analysis showed that the diffusion network can be implemented underwater with the VLC technology providing that the distance between the network nodes is less than 10 meters. Also, in order to guarantee the convergence of the adaptive network, the water salinity level and temperature must not exceed the values that are presented in our simulations.

    Keywords: Diffusion adaptation, Visible light communication, Underwater, Optical turbulence, Log-normal distribution, Convergence, Steady-State
  • Mohammad Rasoul Hosseinnezhad *, Javad Nourinia, Changiz Ghobadi

    A new design of a dual-band printed dipole antenna with integrated balun is presented in this study. The antenna in simple form is composed of a printed dipole, integrated balun, a Γ-shaped feed, and a square-shaped ground plane, which achieves a fundamental resonance at 2.4 GHz frequency. A pair of rectangular-shaped resonators are positioned on two sides of the Γ-shaped feed in the second designing step innovatively to accomplish the additional resonance at 5.5 GHz as the second frequency band of the WLAN. Two electromagnetically coupling mechanisms prepared between the Γ-shaped feed and dipole arms, and rectangular-shaped resonators, which lead to creating two operating frequency bands. An equivalent circuit and a parametric study presented to explain the antenna performance in this work. Experiments approve that the proposed dual-band antenna has two impedance bandwidths of 14.1% (2.23-2.57 GHz) and 25.7% (4.83-6.26 GHz) with average gains of 12.10 dBi and 6.36 dBi over the first and second frequency bands, respectively, which is cover the 2.4/5.5 GHz WLAN frequency bands successfully.

    Keywords: Dual-Band Antenna, Printed Dipole, Integrated Balun, WLAN Application
  • Sirous Tannaz *, Changiz Ghobadi, Javad Nourinia

    Merging the adaptive networks with the free space optical (FSO) communication technology is a very interesting field of research because by adding the benefits of this technology, the adaptive networks become more efficient, cheap and secure. This is due to the fact that FSO communication uses unregistered visible light bandwidth instead of the overused radio spectrum. However, in spite of all the benefits of FSO communication, this technology suffers from optical noise and turbulence. In this paper, we investigate the exact effect of the negative exponential and k-distribution modeled very strong turbulence conditions on the performance of diffusion adaptive networks. The simulation and theoretical results based on the steady state Mean square deviation (MSD) and Excess mean square Error (EMSE) vlaues show the deteriorating effects of these link models on diffusion networks. The FSO communication technology, while very profitable and applicable, is not always a suitable means of implementing wireless networks. For this reason, we suggested the channel estimation for these conditions.

    Keywords: Log-normal distribution, Turbulence, Negative-exponential, K-distribution, FSO, distributed diffusion networks
  • Ehsan Mostafapour *, Changiz Ghobadi, Javad Nourinia, Mehdi Chehel Amirani
    in this paper we focus on the tracking performance of incremental adaptive LMS algorithm in an adaptive network. For this reason we consider the unknown weight vector to be a time varying sequence. First we analyze the performance of network in tracking a time varying weight vector and then we explain the estimation of Rayleigh fading channel through a random walk model. Closed form relations are derived for MSE, MSD and EMSE of analyzed network in tracking Rayleigh fading channel and random walk model. Comparison between theoretical and simulation results shows a perfect match and verifies performed calculations.
    Keywords: Distributed estimation, incremental strategies, non, stationary environment, Rayleigh fading
  • محمود عباسی لایق *، چنگیز قبادی، جواد نوری نیا، بهمن محمدی
    پیش زمینه و هدف
    سرطان پستان از نوع گسترده از شایع ترین سرطان در زنان جهان است. بنابراین، بسیاری از کشورها به جهت تشخیص سرطان در مراحل اولیه برنامه های غربالگری را شروع کرده اند. به منظور تشخیص سرطان پستان به صورت سه بعدی با استفاده از بردارهای پشتیبان از فرضیه تشخیص جسم دفن شده استفاده گردیده است. فرستنده ها و گیرنده ها در قسمت بالای پستان قرار می گیرند. هر فرستنده موج الکترومغناطیسی تک رنگ را تشعشع می کند. تومورها داخل بافت پستان (خروجی) و مقادیر مربوط به میدان الکتریکی جمع آوری شده توسط گیرنده ها (ورودی) می باشند.
    مواد و روش ها
    یک هندسه مسطح پیشنهادی را در نظر بگیرید، به طوری که در آن یک بیمار به پشت خوابیده و پستان به طور طبیعی پهن شده است. بافت سرطانی به صورت یک شبکه مشبک سه بعدی از سلول های طبقه بندی شده در نظر گرفته می شود. به دلیل اینکه بافت پستان را بتوان با درجه بالایی از دقت به صورت محیط خطی در نظر گرفت، سیگنال های دریافتی در فرکانس تک رنگ می باشند. اختصاص دادن یک احتمال پسین متعلق به یک بافت بدخیم با در نظر گرفتن میدان الکتریکی مناسب است.
    بحث و نتیجه گیری
    نتایج بر روی داده های الکترومغناطیسی مرکب از مواد مصنوعی با استفاده از روش المان محدود و روش های لایه های کاملا تطبیقی انجام پذیرفته است. همچنین محیط های نویزی برای شبیه سازی واقعی اندازه گیری سیگنال در نظر گرفته شده است. محدوده هایی برای پارامترهای مدل با کمترین تعداد بردارهای پشتیبان انتخاب می شود. تقریبا تمامی نمونه ها در مجموعه آموزش به بردارهای پشتیبان تبدیل می شوند. با معیارهای مختلف بهترین مدل انتخاب می شود. موقعیت های واقعی تومور با مربع های سفید برجسته مشخص می شوند. وابستگی قابلیت پیش بینی در عمق موقعیت تومور قابل مشاهده نیست مگر اینکه تومور دقیقا زیر لایه پوست قرار بگیرد. همچنین باید یادآور شد که منبع تشعشعی منفرد (دوقطبی) در این کار استفاده شده است. احتمالا تابش حوزه در امتداد محورهای افقی که توسط یک دوقطبی ایجاد می شود به میزان کافی همگن نیست لذا منابع تشعشعی چندگانه به عنوان روش بالقوه برای افزایش کیفیت پیش بینی پیشنهاد می گردند. نگاشت های احتمالی به دست آمده حاکی از این است که ناحیه اطراف تومور معمولا به طور واضحی متفاوت از سایر مقادیر احتمالی می باشد.
    کلید واژگان: سرطان پستان، موج الکترومغناطیسی، ماشین بردار پشتیبان
    Mahmood Abbasi Layegh *, Changiz Ghobadi, Javad Nourinia, Bahman Muhammadi
    Background and Aims
    Breast cancer is one of the most prevalent non-skin-related malignancies among women in the world. Thus، many countries have commenced screening test in early stages in order to diagnose breast cancer. Buried object detection is performed in the present work to detect 3-D breast cancer applying SVM classifier. Some transmitters and receivers are located above the breast. Each transmitter radiates monochromatic electromagnetic wave.
    Materials and Methods
    When a patient is positioned in a supine position، the breast is naturally flattened. The breast tissue is considered as 3-D lattice of classification cells. Since breast tissue can be considered with high order of accuracy as a linear medium، the received signals are monochromatic.
    Results
    Some particular ranges of parameters have been covered during model selection. Almost all samples in the training set were converted to support vectors. It is worthy to remind that single radiation source (dipole) has been used for the present work.
    Conclusion
    The simulation has been carried out on synthetic electromagnetic data obtained by means of Finite Element Method and Perfectly Matched Layers techniques. Noisy environments have been considered as well in order to simulate realistic conditions of signal measurement. The real positions of the tumor are marked by white contour squares. The dependence of the prediction quality on the depth of the tumor location is not observable unless the tumor is directly under the skin layer. Probability maps obtained demonstrate that the region around the tumor location usually clearly stands out against the background of overall probability values.
    Keywords: Breast cancer, Electromagnetic wave, Support vector machine, Finite element method
  • Maryam Majidzadeh, Changiz Ghobadi, Javad Nourinia
    In this paper, a novel CPW-fed antenna is presented for UWB applications. The antenna mainly comprises of a simple circular patch and a modified ground plane. The inclusion of two novel symmetrical rectangular slots with inner area of 3×2.8 mm2 to the top corners of the antenna creates a new path for the current and consequently leads to the bandwidth enhancement. A rectangular stub is also adopted to further broaden the antenna impedance bandwidth. The proposed antenna has a compact size of 20×20×1.6 mm3 and covers the wide frequency band of 3-23.5 GHz (154%). Constant gain and suitable radiation patterns are observed for the presented antenna. Good agreement between the simulated and measured results clearly shows the validity of the proposed structure. The design steps and bandwidth enhancement process are discussed in detail.
    Keywords: CPW feed line, UWB antenna, Wide frequency band
  • آزاده ایمانی، جواد نوری نیا، چنگیز قبادی
    در این مقاله یک آنتن چاپی جدید به صورت دایورسیتی پیشنهاد می شود که بر روی یک صفحه زمین به اندازه کارت حافظه کامپیوترهای شخصی (PCMCIA) قرار گرفته است. آنتن با استفاده از دو تک قطبی کاملا متقارن و مشابه که با فاصله کمی از یکدیگر قرار گرفته اند به نحوی طراحی می شود که بتواند در باند فرکانسی GHz5 عمل کرده و و مقدار کوپلینگ متقابل کم، بهره کافی و در نهایت سرعت انتقال اطلاعات مناسبی را ارائه دهد. حوزه کاری آنتن، کاربردهای WLAN GHz2/5 و GHz8/5 و HYPERLAN GHz8/5 و GHz Wimax 5 می باشد. مقدار کم کوپلینگ توسط ساختار بهینه شده صفحه زمین و اعمال شاخه های اضافه بین دو آنتن در پشت زیرلایه حاصل می شود. پترن های تشعشعی اندازه گیری شده برای آنتن هنگام تحریک از هر طرف، رسم شده و مطابق انتظار تمام فضای آزاد را می پوشاند. عملکرد آنتن دایورسیتی با محاسبه پارامترهای مهم آن نظیر ضریب همبستگی و بهره موثر متوسط (MEG) ارزیابی می گردد تا کاربرد آن در دایورسیتی پترن ثابت شود.
    کلید واژگان: آنتن تک قطبی، آنتن دایورسیتی، بهره موثر متوسط، ضریب همبستگی، کاربردهای WLAN
    Azadeh Imani, Javad Nourinia, Changiz Ghobadi
    In this paper a novel printed diversity antenna designed on a ground plane with size of PCMCIA card of a laptop, is proposed. The antenna by using two similar and symmetric monopoles is designed to operate in 5GHz band and present low mutual coupling, sufficient gain and finally suitable data transmit rate. The operation band includes 5.2GHz and 5.8GHz WLAN applications and 5.6GHz HYPERLAN and 5GHz Wimax. The low mutual coupling is achieved by using optimized structure of ground plane and additional branches two monopoles on the back of substrate. The radiation pattern for proposed antenna in resonance frequency is shown when exciting ever monopole and in general cover complimentary space region. The diversity performance is evaluated by calculating the envelope correlation coefficient and mean effective gain to prove that the proposed antenna can provide pattern diversity.
  • Morteza Rezaee, Javad Nourinia, Changiz Ghobadi
    In this paper, a novel planar hybrid multiband antenna formed by a loop-type antenna, a monopole slot antenna, and a coupled planar monopole antenna for the mobile phone is proposed. The loop-type antenna comprises a driven monopole and a coupled strip that printed on the other side of the substrate and short-circuited to the ground. The 0.5λ and 1.0λ mode of the loop-type antenna are excited. Therefore, the 0.5λ mode of the loop-type antenna forms a wide bandwidth of 326 MHz to cover the GSM850/900 operation and the 0.25λ mode of the monopole slot antenna, the 1.0λ mode of the loop-type antenna, and the 0.25λ mode of the coupled monopole antenna provide a wide bandwidth of 1181 MHz to cover the GPS/DCS/PCS/UMTS/WLAN2.4/WiMAX operation. Finally, the 0.5λ mode of the coupled monopole antenna forms a wide bandwidth to cover the WLAN5.2 operation. Moreover, the hybrid antenna occupies a compact area of 16.5 ´ 45 mm2 and it has good radiation characteristics over the operating bands.
سامانه نویسندگان
  • دکتر جواد نوری نیا
    دکتر جواد نوری نیا
    استاد مخابرات، دانشگاه علم و صنعت ایران، تهران، ایران
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