Sharif Digital Repository

There is no doubt that education is the key to development. An important step in evaluating the condition of education in a society is to estimate the rate of return to education in that society. This paper estimates the private rate of return to schooling for men born in 1951–1983 in Iran using a pseudo-panel fixed-effect model. This is the first study that measures unbiasedly the rate of return to schooling in Iran. We construct the pseudo-panel data using six repeated cross sections of Household Expenditures and Income Surveys between 2008 and 2013. Our estimates show that the overall rate of return is around 9% based on the pseudo-panel fixed-effect approach. The estimates reveal a... 

Due to their different sizes and operational characteristics, vehicles other than passenger cars have a different influence on traffic operations especially at intersections. The passenger car equivalent (PCE) is the parameter that shows how many passenger cars must be substituted for a specific heavy vehicle to represent its influence on traffic operation. PCE is commonly estimated using headway-based methods that consider the excess headway utilized by heavy vehicles. In this research, the PCE was estimated based on the delay parameter at three signalized intersections in Tehran, Iran. The data collected were traffic volume, travel time for each movement, signalization, and geometric... 

Many countries use a single water meter for multiple units within a building. This creates a cost externality where the cost of water consumed is spread over all units. Using administrative data from Tehran Water and Wastewater Co. for 2013 and 2014, we find an increase in the number of units on a communal meter on average increases per unit use by 0.4%. Estimation at different levels of units reveals that almost all communal meters have higher per unit water use. The results suggest that removing this externality could save 2.7% water consumption in our sample. © 2018 Elsevier B.V  

Passenger cars (PCs) are a major contributor to urban air pollution, greenhouse gas emissions, and energy security challenges in megacities in developing countries because of their high growth potential. Since the PC fleet changes through time, the projection of air pollutant emissions from PCs is essential for effective emission reduction policymaking. However, the extensive amount of data and proper models are required for this purpose that are not available in many developing countries. Hence, this study develops multiple econometric and emission models and integrate them into a framework to simulate the future stock and activity of PCs and projects PCs’ air pollutants and CO2 emissions... 

Public participation is counted as one of the main indexes in sustainable urban management. Based on their nature, metropolitan cities has several and complex problems. For this purpose Tehran metropolitan area is selected. Quantitative Strategic Planning Matrix (QSPM) weighted through a made-byresearcher questionnaire. The reliability of the model was verified by Cronbach’s alpha coefficient. Evaluation matrix for internal and external factors was equal to 1.944 and 3.413, respectively. The strategies were classified and prioritize by quantitative matrix. Suitable strategies for Tehran city are as follows: developing a strategic plan in field of social control participatory management for... 

The present study was conducted to investigate the impacts of retrofitted CNG vehicles on air pollutant emissions in Tehran over a 20 years period using available statistical data, precise automobile tests, data analysis, and LEAP Software. The obtained results revealed an increase in air pollutant emissions including CO (equal to 1030.77 thousand tons), NOx (equal to 1030.77 thousand tons), THC (269.02 thousand tons) and CO2 (equal to 38.43 thousand tons) resulting from utilizing retrofitted CNG vehicles within the studied period. Considering the obtained results, if the current trend of producing retrofitted CNG vehicles continues, a total cost of 435 million USD will impose on the... 

This paper focuses on low frequency airline service patronage using the data from a survey conducted at Imam Khomeini International Airport in Tehran, Iran. It uses Dominance-based Rough Set Approach (DRSA) for modeling passengers' choices. We compare the method with discrete choice models using a prediction potential measure. Unlike discrete choice methods, it can use qualitative and categorized data without having to transform them into dummy variables. It is found that the prediction accuracy of the proposed technique is better than that of the discrete choice model for the case under consideration  

Nowadays, transportation sector consumes about 27 percent of the whole energy in Iran. Therefore, after domestic and business sectors which consume about 40 percent of the whole energy, transportation is placed in the second rank. However, the financial value of transportation is of the highest importance. Moreover, having 55percent of gasoline product consumption transportation has been also ranked as the largest consumer of gasoline products. Gasoline consumption in transport showed an increase until 1979. During 1980-1981, it decreased slightly and from 1982 have had a permanent upward trend. Oil products consumption in transport sector in 1950 has been less than average 15 million... 

Urban and transportation planners have put a special focus on students' health and fitness in the past decade, however they struggle to find effective policies to promote walking and biking for school trips. Commuting to school is an opportunity to embed a regular physical activity in students' daily routines and prevent many health issues that are stimulated by physical inactivity during childhood. A three level nested logit model is introduced to explain the motives behind school trip modal selection. Four choice situations, namely walking, driving, school busing, and taking public transit are considered. This study, particularly, underscored the significance of model misspecification in... 

Efficient operation of urban water systems necessitates accurate water demand forecasting. We present daily, weekly, and monthly water demand forecasting using dynamic artificial neural network (DAN2), focused time-delay neural network (FTDNN), and K-nearest neighbor (KNN) models for the city of Tehran. The daily model investigates whether partitioning weekdays into weekends and non-weekends can improve forecast results; it did not. The weekly model yielded good results by using the summation of the daily forecast values into their corresponding weeks. The monthly results showed that partitioning the year into high and low seasons can improve forecast accuracy. All three models offer very... 

Over the past few decades, industrial development has caused a dramatic increment in greenhouse gas (GHG) emissions, as a leading cause of climate change. Modifying the industrial plants' environmental performance is the main pillar of improving efficiency that can reduce the waste of resources and make achieving lower-cost global emission reduction targets of the Kyoto protocol's clean development mechanism (CDM) possible. Considering the essentiality of knowledge-based research in increasing the awareness of policymakers by providing better access to accurate and reliable information, an analytical survey on efficiency in oil, gas, and petrochemical industries has been conducted by... 

Purpose: In this study we aimed to develop an optimized prediction model to estimate a fine-resolution grid of ground-level PM2.5 levels over Tehran. Using remote sensing data to obtain fine-resolution grids of particulate levels in highly polluted environments in areas such as Middle East with the abundance of brightly reflecting deserts is challenging. Methods: Different prediction models implementing 3 km AOD products from the MODIS collection 6 and various effective parameters were used to obtain a reliable model to estimate ground-level PM2.5 concentrations. In this regards, the linear mixed effect model (LME), multi-variable linear regression model (MLR), Gaussian process model (GPM),... 

Thermal stratification accompanied by a release of nutrients from sediment is a serious problem for the management of water quality. Water aeration and mixing technology can be widely used to control endogenous pollution and algae growth in reservoirs and lakes by water quality managers. In this research, a diffuser aeration system, was installed in a water column, in the Mamloo stratified Reservoir; and the impact of artificial aeration was brought under extensive assessment in relevance with the qualitative and biological parameters of the water, during the preliminary 6 d of aeration. The results showed that the thermal stratification was remarkably disturbed. After aeration, the amount... 

This article introduces the concept of latecomer systems integration capability (LSIC) as a construct for theory development in the area of emergence and competitiveness of producers of complex capital goods from developing economies. The study draws on three bodies of the literature to conceptualize LSIC and then presents an in-depth case study of the development of LSIC in a major Iranian firm engaged in producing electricity generation systems. Although an exploratory study, the findings suggest that, in this case, LSIC evolved in a fairly short period of time from simple low-cost project management skills to innovative capabilities, supported by some sophisticated engineering and design... 

Over recent years, frequent involvements in claims have been inevitable due to unpredictable economic changes and increasing complexities in construction industry. Therefore, even appropriately made contracts are not exempted from claims. On the other hand, construction contract claims are time-consuming, expense-involving and most likely leading to unsatisfactory results. However, there may be some positive outcomes, such as time extension or compensation of damages. To launch investigations, a list of important and frequent claims in oil and gas industry projects of Iran was extracted after a succinct documents review. Further, the most important claim causes were identified through... 

Based on International Energy Agency studies, achievement of 450 ppm CO2-equivalent emission target in global emission means that the CO2 emissions in 2050 must be reduced to %50 of 2005 level, and this implies that a portfolio of emission reduction policies and strategies need to be exploited through current century. At the present time, Carbon Capture and Storage (CCS) Technology is a dominant strategy among all the long-term carbon abatement strategies in many countries. Nevertheless, its potential as a climate mitigating option will be proved, only if it is implemented in the countries which are developing at a great pace and taking advantage of fossil fuels in order to afford their...