Sharif Digital Repository

Using 3-D scanned data to analyze and extract pore network plays a vital role in investigation of porous media's characteristics. In this paper, a new simple method is developed to detect pores and throats for analyzing the connectivity and permeability of the network. This automated method utilizes some of the common and well-known image processing functions which are widely accessible by researchers and this has led to an easy algorithm implementation. In this method, after polishing and quality control of images, using city-block distance function and watershed segmentation algorithm, pores and throats are detected and 3-D network is produced. This method can also be applied on 2-D images... 

Recent progress in developing artificial neural network (ANN) metamodels has paved the way for reliable use of these models in the prediction of air pollutant concentrations in urban atmosphere. However, improvement of prediction performance, proper selection of input parameters and model architecture, and quantification of model uncertainties remain key challenges to their practical use. This study has three main objectives: to select an ensemble of input parameters for ANN metamodels consisting of meteorological variables that are predictable by conventional weather forecast models and variables that properly describe the complex nature of pollutant source conditions in a major city, to... 

Because of the recent frequent observations of major dust storms in southwestern cities in Iran such as Ahvaz, and the importance of the ionic composition of particulate matters regarding their health effects, source apportionment, etc., the present work was conducted aiming at characterizing the ionic composition of total suspended particles (TSP) and particles on the order of ∼10 μm or less (PM10) during dust storms in Ahvaz in April-September 2010. TSP and PM10 samples were collected and their ionic compositions were determined using an ion chromatography. Mean concentrations of TSP and PM10 were 1,481.5 and 1,072.9 μg/m 3, respectively. Particle concentrations during the Middle Eastern... 

Traffic assignment is a step of travel demand estimation. Given a trip origin-destination demand matrix, this step determines traffic flow in each link, according to assumptions based on the behavior of drivers. Conventional assignment algorithms, which are mostly based on the Wardrop first principle of user equilibrium, assume that all drivers choose the shortest path to the destination, based on the same travel time computed by travel time functions. However, in reality, driver perception of travel time varies for a specific route. This paper presents a traffic assignment algorithm which assumes that driver perception of travel time affects route choices. Fuzzy set theory is used to define... 

Wind speed is the most important parameter in the design and study of wind energy conversion systems. The weibull distribution is commonly used for wind energy analysis as it can represent the wind variations with an acceptable level of accuracy. In this study, the wind data for 11 cities in Iran have been analysed over a period of one year. The Goodness of fit test is used for testing data fit to weibull distribution. The results show that this data fit to weibull function very well. The scale and shape factors are two parameters of the weibull distribution that depend on the area under study. The kinds of numerical methods commonly used for estimating weibull parameters are reviewed. Their... 

In this paper, intelligent traffic surveillance system as an important part of a smart resilient city is reviewed. The smart traffic control system is very important in improving the lifestyle by decreasing the traffic saturation and air pollution. Still, multi-camera vision is more helpful in implementing different automatic traffic surveillance systems. Apart from their superior features, existing multi-camera surveillance systems suffer from computational complexity and degraded accuracy. The main reason for these shortcomings arises from image processing errors. These errors depend on the image content and thus are not predictable. To overcome this shortage, three-dimensional (3D)... 

Geotechnical engineering is a fundamental subject in civil and environmental engineering that engineers are required to refer to when any type of retrofitting, design or construction of projects and developments are encountered in a city or in a rural area. Indeed in many projects like geotechnical structures, such as earth dams, geotechnical engineering is the main subject. In this paper, the role of geotechnical engineering in sustainable and resilient cities is elaborated mainly through a series of questions and answers. Also, some related geotechnical engineering research, that is in hands in Civil Engineering Department of Sharif University, is discussed in this paper. A unique... 

The climate change and human development in lake catchments have put these habitats in drying conditions, e.g. Aral Sea in Asia, Lake Chad in Africa, Lake Mead in USA, Lake Urmia in Iran, etc. These ecosystems play an important role in social, ecological, and economic activities. Lake Urmia, recognized as an international wetland in 1973 and located in Iran, which is the second largest hypersaline lake in the world, is in the same state. Lake Urmia biologically and ecologically is one of the most interesting places in the world. This lake is a habitat for various species. The lake's surface has shrunken from 6000 km2 to 900 km2 in 2013. The statistics indicate that the population has... 

Network pricing is an effective transportation demand management scheme to reduce traffic and control air pollution, particularly in CBDs. In this study, congested area cordon entry and Park-and-Ride (P/R) facility use are priced for automobiles. Increase in these prices may reduce private auto demand by impelling some of the auto passengers to use public transport from the origin of their trips, or encouraging them to park their cars at the P/R facilities and use buses, or pay the entrance fee and drive inside the cordon. A Markov decision process has been devised to find an optimal policy for pricing the P/R facilities and cordon entry in a city within a variable demand context. This... 

A part of resilience and sustainability in any urban environment is establishing and maintaining health. Sustainability in health is a dynamic process in which growth of physical, mental, and social health is guaranteed. A city is sustainable when all aspects of life, such as economy, environment, health, and infrastructure, are well defined and very often subjected to optimization  

In the 21st century, the world population is growing at a spiraling pace. Much of this growth is occurring in developing countries, where access to food, sanitary water, education, and health is severely limited. The ever-increasing urbanization highlighted the need for sustainable development based on human-environment interaction. The excessive and unplanned expansion of cities has resulted in numerous environmental predicaments due to clearly emphasized economic issues at the expense of social and environmental concerns. The most significant features of megacities are indicated in this paper and the environmental, social, physical, and economic criteria are addressed in order to attain... 

Estimanon of the origin-destination trip danad matrix (O-D) plays a key role in travel analysis and transportation planning and operations. Many researchers have developed different O-D maths estimation mediods using traffic counts, which allow simple data collection as opposed to die costly traditional direct estimation methods based on home and roadside interviews. In mis papet, a new fuzzy O-D matrix estimation model (FODMEM) is proposed to estimate die O-D matrix from traffic count. A gradient-based aigoridnn. containing 3 fuzzy rule based approach to control die estimated O-D matrix changes, is proposed to solve FODMEM Since link data only represents a snapshot situation, resulting in... 

In the contemporary era, the world is confronting numerous challenges that should be dealt with in the near future like effective management of energy, necessity for economic development, reducing environmental challenges, quality and security of life of its inhabitants. The growing concentration of the global inhabitants into towns and cities puts the urban areas in the center of the concerns and make them vital stakeholders for the viable growth strategy of the world. Consequently, Cyber-physical systems (CPS) can play a significant role in their adaptation to smart cities applications and projects. This paper aims to give an overview of the smart city concept and emerging technologies in... 

Land use regression (LUR) has not been applied thus far to ambient alkylbenzenes in highly polluted megacities. We advanced LUR models for benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX using measurement based estimates of annual means at 179 sites in Tehran megacity, Iran. Overall, 520 predictors were evaluated, such as The Weather Research and Forecasting Model meteorology predictions, emission inventory, and several new others. The final models with R2 values ranging from 0.64 for p-xylene to 0.70 for benzene were mainly driven by traffic-related variables but the proximity to sewage treatment plants was present in all models indicating a major local...