Sharif Digital Repository

Asphalt concrete is a heterogeneous and multi-phase material that consists of aggregates, asphalt binder, and pores. These components create a complex microstructure. There is no consensus on how to quantify the microstructure and the required parameters from two-dimensional images. The load transfer can be managed by aggregate-aggregate or aggregate-mastic interactions that depend on the gradation, aggregate internal structure, and asphalt binder viscoelastic properties. The most important internal structure indices affecting the behavior of HMA are aggregate orientation, contact orientation, contact length, and number of contact points. In this paper, the influence of aggregate structure... 

Critical crescent moon detection is a new subject in astronomical image processing. Astronomers take photos with valuable astronomical calculations using CCD cameras and telescopes. Crescent moon might not be visible in such photos, so they must be enhanced. For this purpose, we apply common image processing methods on crescent moon images such as power operator, gamma transformation, global and local histogram equalization, POSHE, CLAHE, local enhancement, gain/offset correction, homomorphic filtering, SSR, MSR, MSRCR, wavelet and curvelet transformations. Second, we use our new methods like PB, POSP, HShistV, CurvHShistV and local brightness intensity enhancement to detect the crescent.... 

Robotics has become a rapidly growing science that will enter the life of all classes of people in a few years. That is why we have tried to work in this field. The project that we are going to describe here is a robotic rescue team that uses its designed systems and utilized detection methods to help people and help rescuers to accurately detect victims when natural disasters such as floods and earthquakes occur. However, in addition to the functions listed, this robotic team can help in the identification of historic centers, help to protect the environment, be useful in mapping, and help the traffic police. The technologies used in this project can be implemented in various industrial... 

Context. Photometric monitoring of the variability of brown dwarfs can provide useful information about the structure of clouds in their cold atmospheres.The brown-dwarf binary system Luhman 16AB is an interesting target for such a study, because its components stand at the L/T transition and show high levels of variability. Luhman 16AB is also the third closest system to the solar system, which allows precise astrometric investigations with ground-based facilities. Aims. The aim of the work is to estimate the rotation period and study the astrometric motion of both components. Methods. We have monitored Luhman 16AB over a period of two years with the lucky-imaging camera mounted on the... 

The ability of wearable cameras to continuously capture the first person viewpoint with minimal user interaction, has made them very attractive in many application domains. Wearable technology today is available and useful but not widely used and accepted due to various challenges mainly privacy concerns. In this paper, we introduce a novel efficient privacy-aware framework for wearable cameras that can protect all sensitive subjects such as people, objects (e.g, display screens, license plates and credit cards) and locations (e.g, bathrooms and bedrooms). It uses the contextual information obtained from the wearable's sensors and recorded images to identify the potential sensitive subjects... 

The goal of robust parameter estimation is developing a model which can properly fit to data. Parameter estimation of a geometric model, in presence of noise and error, is an important step in many image processing and computer vision applications. As the random sample consensus (RANSAC) algorithm is one of the most well-known algorithms in this field, there have been several attempts to improve its performance. In this paper, after giving a short review on existing methods, a robust and efficient method that detects the gross outliers to increase the inlier to outlier ratio in a reduced set of corresponding image points is proposed. It has a new hypothesis and verification scheme which... 

The goal of robust parameter estimation is developing a model which can properly fit to data. Parameter estimation of a geometric model, in presence of noise and error, is an important step in many image processing and computer vision applications. As the random sample consensus (RANSAC) algorithm is one of the most well-known algorithms in this field, there have been several attempts to improve its performance. In this paper, after giving a short review on existing methods, a robust and efficient method that detects the gross outliers to increase the inlier to outlier ratio in a reduced set of corresponding image points is proposed. It has a new hypothesis and verification scheme which... 

Color information of natural images can be considered as a highly correlated vector space. Many different color spaces have been proposed in the literature with different motivations toward modeling and analysis of this stochastic field. Recently, color transfer among different images has been under investigation. Color transferring consists of two major categories: colorizing grayscale images and recoloring colored images. The literature contains a few color transfer methods that rely on some standard color spaces. In this paper, taking advantages of the principal component analysis (PCA), we propose a unifying framework for both mentioned problems. The experimental results show the... 

Analysis of the multispectral remotely sensed images of the areas destroyed by an earthquake is proved to be a helpful tool for destruction assessments. The performance of such methods is highly dependant on the preprocess that registers the two shots before and after an event. In this paper, we propose a new fast and reliable change detection method for remotely sensed images and analyze its performance. The experimental results show the efficiency of the proposed algorithm. Copyright © 2006 Hindawi Publishing Corporation. All right reserved  

Travel demand information in the form of the origin–destination (OD) matrix plays an essential role in studying urban traffic management and network design. The present study takes a novel step toward urban traffic analysis using data mining of processed images of real-time traffic maps as a location-based data model, in which the data were analyzed by software programs such as KNIME and Python workspaces and comparing the results with the conventional traffic assignment results. Thus, we investigated a real-time OD matrix based on the trip-per-vehicle by automatic number-plate recognition (ANPR) cameras for the congestion charge zone (CCZ) of Tehran, Iran. The obtained matrix was assigned... 

Foliar characteristics, especially the overall leaf shape, are useful features for the taxonomic identification of plants. Computer-aided plant species identification systems make it possible to investigate a large number of leaves in a short period of time. In this study, a fully automatic system was developed to accurately classify eight species of maples (Acer L.) in Iran using the leaf shape characteristics of harvested leaves. Maples show a broad range of leaf morphology, and the provided dataset is a diverse collection of simple leaves which can be a good representative of woody plant leaves with any overall shape and margin pattern. The applied method consisted of preprocessing,... 

Asphaltene deposition has hindered oil production from asphaltenic oil reservoirs through deposition in reservoir rock and surface facilities. This paper investigates the effect of resin on asphaltene deposition at different pressures. To investigate the asphaltene deposition in the presence of resins at reservoir temperature and different pressures, a pressure, volume, and temperature (PVT) visual cell was designed. A high-resolution microscope and image processing software were used to detect and determine the amount of deposited asphaltene as well as its size distribution at different conditions. Two types of Iranian crude oils with different potential of deposition (low and high) were... 

A totally computerized image processing program package is developed to analyze the SEM images of membrane surface and cross-section. Pore size distribution and porosity of the fabricated membranes are determined using the proposed image processing procedure. Furthermore, effect of coagulation bath temperature on the morphology and mechanical properties (such as tensile strength, strain break, tensile energy absorbent, and tensile stiffness) of Polysulfone (PSf) membranes are investigated. The results reveal that the mechanical properties are higher when N-methyl-2-pyrrolidone (NMP) is used as solvent. Also, an increase in the coagulation bath temperature caused a monotonous increase in the... 

In this paper, we consider resonant interaction between a surface wave and sub-harmonic interfacial waves forming a two-dimensional pattern at the interface between two fluid layers. The resulting interfacial pattern changes both in time and space. An image processing technique is proposed to extract information about the evolution of the component interfacial waves in a wave flume. The technique proved to give accurate and consistent results when applied to different stages of the interaction. The experimental measurements were used to verify the theoretical predictions. The method can be used for detection of some other wave motions