حسن پور, حمید

[ 1 ] - ابرتفکیک‌پذیری: مروری بر روش‌های موجود

[ 2 ] - Investigation of Hydrodynamic Derivatives of an AUV Based on the Water Tunnel Testing Maneuvers

Coefficients or hydrodynamic derivatives of autonomous underwater vehicles play a key role in their development. The most popular way for the estimation of coefficient is to implement captive model tests such as straight line tests and planar motion mechanism tests in towing tanks. In this paper, investigation of hydrodynamic derivatives was performed based on the water tunnel maneuvers. Forces...

[ 3 ] - تشخیص وقوع‌گیر رشته حفاری با تحلیل سیگنال گشتاور

وقوع گیر در رشته حفاری در صنعت نفت یکی از مشکلات پرهزینه و وقت‌گیر عملیات حفاری بوده که پارامترهای حین حفاری، نظیر گشتاور رشته حفاری و ساختار زمین در وقوع گیر رشته حفاری تاثیر مستقیمی در این مشکل دارند. تجارب نشان داده است در زمان گیر رشته حفاری، گشتاور به‌طور لحظه‌ای افزایش و سرعت چرخش مته کاهش می‌یابد. از آنجائی‌که در تشخیص این تغییرات امکان بروز خطای انسان و عدم دقت کافی وجود دارد لذا با شنا...

[ 4 ] - یک روش مؤثر برای قطعه بندی تصاویر بااستفاده از ساختار پیکسونی و به کارگیری مفهوم میدان تصادفی مارکوف

یکی از مباحث مهم و نسبتاً مشکل در پردازش تصویر، تفکیک تصویر به اجزای سازندة ( قطعه بندی) آن است که در موفقیت یا ناموفق بودن تحلیل تصویر بسیار مؤثر است. در این مقاله، بااستفاده از مفهوم پیکسون و میدان های تصادفی مارکوف روش جدیدی برای قطعه بندی تصاویر پیشنهاد می شود. در روش پیشنهادی ابتدا تصویر به صورت یک تصویر پیکسونی مدل می شود و تنها پیکسون های تصویر ارزیابی می شود، نه همة پیکسل های آن. سپس باا...

[ 5 ] - Improving Super-resolution Techniques via Employing Blurriness Information of the Image

Super-resolution (SR) is a technique that produces a high resolution (HR) image via employing a number of low resolution (LR) images from the same scene. One of the degradations that attenuates performance of the SR is the blurriness of the input LR images. In many previous works in the SR, the blurriness of the LR images is assumed to be due to the integral effect of the image sensor of the im...

[ 6 ] - A Modfied Self-organizing Map Neural Network to Recognize Multi-font Printed Persian Numerals (RESEARCH NOTE)

This paper proposes a new method to distinguish the printed digits, regardless of font and size, using neural networks.Unlike our proposed method, existing neural network based techniques are only able to recognize the trained fonts. These methods need a large database containing digits in various fonts. New fonts are often introduced to the public, which may not be truly recognized by the Opti...

[ 7 ] - Behavioral Analysis of Traffic Flow for an Effective Network Traffic Identification

Fast and accurate network traffic identification is becoming essential for network management, high quality of service control and early detection of network traffic abnormalities. Techniques based on statistical features of packet flows have recently become popular for network classification due to the limitations of traditional port and payload based methods. In this paper, we propose a metho...

[ 8 ] - Image Enhancement Using an Adaptive Un-sharp Masking Method Considering the Gradient Variation

Technical limitations in image capturing usually impose defective, such as contrast degradation. There are different approaches to improve the contrast of an image. Among the exiting approaches, un-sharp masking is a popular method due to its simplicity in implementation and computation. There is an important parameter in un-sharp masking, named gain factor, which affects the quality of the enh...

[ 9 ] - A Novel Image Structural Similarity Index Considering Image Content Detectability Using Maximally Stable Extremal Region Descriptor

The image content detectability and image structure preservation are closely related concepts with undeniable role in image quality assessment. However, the most attention of image quality studies has been paid to image structure evaluation, few of them focused on image content detectability. Examining the image structure was firstly introduced and assessed in Structural SIMilarity (SSIM) measu...

[ 10 ] - Deblocking Joint Photographic Experts Group Compressed Images via Self-learning Sparse Representation

JPEG is one of the most widely used image compression method, but it causes annoying blocking artifacts at low bit-rates. Sparse representation is an efficient technique which can solve many inverse problems in image processing applications such as denoising and deblocking. In this paper, a post-processing method is proposed for reducing JPEG blocking effects via sparse representation. In this ...

[ 11 ] - People Re-identification in Non-overlapping Field-of-views using Cumulative Brightness Transform Function and Body Segments in Different Color Spaces

Non-overlapping field-of-view (FOV) cameras are used in surveillance system to cover a wider area. Tracking in such systems is generally performed in two distinct steps. In the first step, people are identified and tracked in the FOV of a single camera. In the second step, re-identification of the people is carried out to track them in the whole area under surveillance. Various conventional fea...

[ 12 ] - A Geometric View of Similarity Measures in Data Mining

The main objective of data mining is to acquire information from a set of data for prospect applications using a measure. The concerning issue is that one often has to deal with large scale data. Several dimensionality reduction techniques like various feature extraction methods have been developed to resolve the issue. However, the geometric view of the applied measure, as an additional consid...

[ 13 ] - Improving Dark Channel Prior for Single Image Dehazing

This paper proposes an improved dark channel prior for removing haze from images. Dark channel prior is an effective method for removing haze. Dark channel is an image in the same size as the hazy image which is obtained by dividing the RGB images into windows and for each window, the minimum of each R, G and B channels are calculated. Then again the minimum of these three values is calculated ...

[ 14 ] - Image Denoising Using Anisotropic Diffusion Equations on Reflection and illumination Components of Image

This paper proposes a new hybrid method based on Homomorphic filtering and anisotropicdiffusion equations for image denoising. In this method, the Homomorphic filtering extracts the reflectionand illumination components of a noisy image. Then a suitable image denoising method based onanisotropic diffusion is applied to each components with its special user-defined parameters .This hybridscheme ...

[ 15 ] - An Improved Automatic EEG Signal Segmentation Method based on Generalized Likelihood Ratio

It is often needed to label electroencephalogram (EEG) signals by segments of similar characteristics that are particularly meaningful to clinicians and for assessment by neurophysiologists. Within each segment, the signals are considered statistically stationary, usually with similar characteristics such as amplitude and/or frequency. In order to detect the segments boundaries of a signal, we ...

[ 16 ] - Image Zooming using Non-linear Partial Differential Equation

The main issue in any image zooming techniques is to preserve the structure of the zoomed image. The zoomed image may suffer from the discontinuities in the soft regions and edges; it may contain artifacts, such as image blurring and blocky, and staircase effects. This paper presents a novel image zooming technique using Partial Differential Equations (PDEs). It combines a non-linear Fourth-ord...

[ 17 ] - Detection of Alzheimer\\\\\\\'s Disease using Multitracer Positron Emission Tomography Imaging

Alzheimer's disease is characterized by impaired glucose metabolism and demonstration of amyloid plaques. Individual positron emission tomography tracers may reveal specific signs of pathology that is not readily apparent on inspection of another one. Combination of multitracer positron emission tomography imaging  yields promising results. In this paper, 57 Alzheimer's disease neuroimaging ini...

[ 18 ] - Image Enhancement via Reducing Impairment Effects on Image Components

In this paper, a new approach is presented for improving image quality. It provides a new outlook on how to apply the enhancment methods on images. Image enhancement techniques may deal with the  illumination, resolution, or distribution of pixels values. Issues such as the illumination of the scene and reflectance of objects affect on image captures. Generally, the pixels value of an image is ...

[ 19 ] - Investigating Embedded Question Reuse in Question Answering

The investigation presented in this paper is a novel method in question answering (QA) that enables a QA system to gain performance through reuse of information in the answer to one question to answer another related question. Our analysis shows that a pair of question in a general open domain QA can have embedding relation through their mentions of noun phrase expressions. We present methods f...

[ 20 ] - Boosting Passage Retrieval through Reuse in Question Answering

Question Answering (QA) is an emerging important field in Information Retrieval. In a QA system the archive of previous questions asked from the system makes a collection full of useful factual nuggets. This paper makes an initial attempt to investigate the reuse of facts contained in the archive of previous questions to help and gain performance in answering future related factoid questions. I...

[ 21 ] - Image Quality Enhancement Using Pixel Wise Gamma Correction

This paper presents a new automatic image enhancement method by modifying the gamma value of its individual pixels. Most of existing gamma correction methods apply a uniform gamma value across the image. Considering the fact that gamma variation for a single image is actually nonlinear, the proposed method locally estimates the gamma values in an image using support vector machine. First, a dat...

[ 22 ] - An Improved Pixon-Based Approach for Image Segmentation

An improved pixon-based method is proposed in this paper for image segmentation. In thisapproach, a wavelet thresholding technique is initially applied on the image to reduce noise and toslightly smooth the image. This technique causes an image not to be oversegmented when the pixonbasedmethod is used. Indeed, the wavelet thresholding, as a pre-processing step, eliminates theunnecessary details...

[ 23 ] - Adaptive Segmentation with Optimal Window Length Scheme using Fractal Dimension and Wavelet Transform

In many signal processing applications, such as EEG analysis, the non-stationary signal is often required to be segmented into small epochs. This is accomplished by drawing the boundaries of signal at time instances where its statistical characteristics, such as amplitude and/or frequency, change. In the proposed method, the original signal is initially decomposed into signals with different fr...

[ 24 ] - An Optimized Online Secondary Path Modeling Method for Single-Channel Feedback ANC Systems

This paper proposes a new method for online secondary path modeling in feedback active noise control (ANC) systems. In practical cases, the secondary path is usually time-varying. For these cases, online modeling of secondary path is required to ensure convergence of the system. In literature the secondary path estimation is usually performed offline, prior to online modeling, where in the prop...

[ 25 ] - A Robust Feedforward Active Noise Control System with a Variable Step-Size FxLMS Algorithm: Designing a New Online Secondary Path Modelling Method

Several approaches have been introduced in literature for active noise control (ANC)systems. Since Filtered-x-Least Mean Square (FxLMS) algorithm appears to be the best choice as acontroller filter. Researchers tend to improve performance of ANC systems by enhancing andmodifying this algorithm. This paper proposes a new version of FxLMS algorithm. In many ANCapplications an online secondary pat...

[ 26 ] - Controlling Common-Mode Voltages in Multilevel Inverters

This paper proposes a novel method based on pulse width modulation techniques toreduce and control the common-mode voltage in three-phase multilevel inverters. Besides controllingthe common-mode voltage, this method is capable of controlling capacitors voltages and load currentswith low switching losses and harmonic contents. In fact, due to the existence of different pulsepatterns and the poss...

[ 27 ] - Image Restoration Using A PDE-Based Approach

 Image restoration is an essential preprocessing step for many image analysis applications. In any image restoration techniques, keeping structure of the image unchanged is very important. Such structure in an image often corresponds to the region discontinuities and edges. The techniques based on partial differential equations, such as the heat equations, are receiving considerable attention i...

[ 28 ] - Design and Implementation of a Software System for Detecting Orthographical or Morphological Errors in Persian Words

This paper presents a new method for analyzing words in the Persian language context to find orthographical and structural errors regardless of the meaning. This technique tokenizes each word in a statement then tries to detect the kind of word, and analyses its correctness in terms of orthography and morphology by means of a lexicon. It should be noted that some words in the Persian language h...

[ 29 ] - Newborn EEG Seizure Detection Based on Interspike Space Distribution in the Time-Frequency Domain

This paper presents a new time-frequency based EEG seizure detection method. This method uses the distribution of interspike intervals as a criterion for discriminating between seizure and nonseizure activities. To detect spikes in the EEG, the signal is mapped into the time-frequency domain. The high instantaneous energy of spikes is reflected as a localized energy in time-frequency domain. Hi...