Sharif Digital Repository

Crash forecasting enables safety planners to take appropriate actions before casualty or loss occurs. Identifying and analyzing the attributes influencing forecasting accuracy is of great importance in road crash forecasting. This study aims to model the forecasting accuracy of 31 provinces using their macroeconomic variables and road traffic indicators. Iran's road crashes throughout 2011–2018 are calibrated and cross-validated using the Holt-Winters (HW) forecasting method. The sensitivity of crash forecast reliability is studied by a regression model. The results suggested that the root mean square error (RMSE) of crash prediction increased among the provinces with higher and more variant... 

Results confirm that Iran like many countries is affected by high climate variability, which has influenced hydroclimatological variables such as temperature, evaporation, precipitation, runoff, and radiation. This study uses Global Land Data Assimilation System (GLDAS) data to assess hydrological cycle changes in Iran during a long period (Jan1948-Jan2017). Results show that hydrometeorological variables have significant changes (p-value<.01) during the period of 2010–2017 relative to the baseline period (2004–2009). Most extreme values of these variables including temperature, evaporation, precipitation, wind, and downward longwave radiation occurred recently (in 2015 to 2017). The average... 

Optimization methods for process integration of industrial networks presented so far have dealt with grass-root situation. For retrofit ones, the actual design of the existing heat exchanger network must be taken into account. Berntsson and Stromberg (1996) developed new Composite Curves for use in a targeting and options scanning in retrofitting. The aim of this development has been to create Pinch Technology based methods, with which the general problems with process integration in Retrofit can be treated. New Pinch Technology based curves for retrofitting of heat exchanger networks have provided a graphical representation of existing HEN, including heaters and utility levels, from which... 

Currently PM2.5 is a major air pollution concern in Tehran, Iran due to frequent high levels and possible adverse impacts. In this study, which is the first of its kind to take place in Tehran, composition and sources of PM2.5 and carbonaceous aerosol were determined, and their seasonal trends were studied. In this regard, fine PM samples were collected every six days at a residential station for one year and the chemical constituents including organic marker species, metals, and ions were analyzed by chemical analysis. The source apportionment was performed using organic molecular marker-based CMB receptor modeling. Carbonaceous compounds were the major contributors to fine particulate mass... 

Dust storms are a common phenomenon in arid and semi-arid regions in West Asia, which has led to high levels of PM10 in local and remote area. The Yazd city in Iran with a high PM10 level located downstream of dust sources in the Middle East and Central Asia. In this study, based on meteorological and PM10 monitoring data, backward trajectory modeling of air parcels related to dust events at Yazd station was performed using the HYSPLIT model in 2012–2019. The trajectory cluster analysis was used to identify the main dust transport pathways and wind systems. Three methods of Cross-referencing Backward Trajectory (CBT), Potential Source Contribution Function (PSCF) and Concentration Weighted... 

The spatiotemporal variability of ambient volatile organic compounds (VOCs) in Tehran, Iran, is not well understood. Here we present the design, methods, and results of the Tehran Study of Exposure Prediction for Environmental Health Research (Tehran SEPEHR) on ambient concentrations of benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX. To date, this is the largest study of its kind in a low- and middle-income country and one of the largest globally. We measured BTEX concentrations at five reference sites and 174 distributed sites identified by a cluster analytic method. Samples were taken over 25 consecutive 2-weeks at five reference sites (to be used for...