Sharif Digital Repository

In this research, trade and transportation trends of Asia-Europe-Africa, in the both intercontinental and intracontinental levels have been analyzed. With analyses which are done in this research, determinant factors for modeling and investigating international bilateral trade in these three continents have been recognized. The relevant time-series data were extracted from centralized and international databases. The examined database consists of 11 variables grouped in four categories: bilateral trade data, transportation, geographical and socio-economic characteristics. Transportation data is based on three different networks. The first network consisted of highway, rail and marine modes... 

Usually the structures are designed based on the fixed-base assumption; however thisassumption is not always correct and the bed flexibility should be considered. This effectwhich is called soil-structure interaction, change the response of structure on both elasticand inelastic behavior. In the regulations for the design of structures on flexible base,generally soil-structure system is replaced with an equivalent fixed base structure; in theway that the design force of soil-structure system with reasonable accuracy can beestimated by equivalent fixed-base structure. In some regulations, dynamic characteristicsof equivalent structure have been determined on elastic state and the results have... 

In the regard of structural health monitoring the identification of the structural modal parameters is essential. Since the different sources (wind, waves, Devices …) induce vibration on an offshore platform, it is impossible to determine the portion of each source in vibration. Thus the methods that analyze vibrations needless of input measurements are more efficient. These methods apply the ambient factors and obtain the modal properties from the structural response. This procedure has no unwanted effect on the serviceability of structure and by placement of sensors on the platform; one can monitor the structural health.
In the present work a two dimensional jacket offshore platform... 

Despite a rather long history of bureaucratic public administration, Iranian public sector has failed to catch up with the ever developing knowledge of fighting corruption in “public procurement”, a critical field of governmental management which accounts for at least 15 percent of GDP around the world. While international organizations like TI and OECD have been broadly active in globalizing the standards of integrity and calling for improvements in the national frameworks of procurement, a reductionist agenda might take the safest path of change by following whatever prescribed by those international bodies. However, there have also been some deeper reflections on the complexities of... 

In economics, choice or behavior is considered as a result of utility optimization. However, there’s much theoretical and experimental evidence that shows human beings suffer from decision-making and judgment errors. This research aiming at examining the relationship between post-choice attitude changes and framing effects as the two instances of those errors designed and implemented a 2 by 2 between-subject lab experiment. The subjects were randomly assigned to one of these four groups. The two treatment groups made their decision after they rated the objects one time and the two control groups did this after they evaluated the objects two times. Another intervention was to manipulate... 

Nanolaunchers are launch vehicles capable of carring light payloads (under 50 kg) to Low Earth orbit and received much attention in the few past years. Launching the nanosatellites grown about 30 times from 2008 to 2017. Since this category of launch vehicles has fewer developing costs and lower thechnology level, they fit developing space technology in our country. Conversely, the demand of high propellant mass fraction and specific impulse may be a serious difficulty to attain this technology.The only operating nanolauncher in the world is SS-520-5 which belongs to Japan and is a three-stage solid propellant launcher. The goal of this project is also the conceptual design and feasiblity... 

The present work was aimed to account a green and eco-friendly synthesis of copper oxide nanoparticles using Salvia hispanica extracts for the first time.The synthesized copper oxide nanoparticles were fully characterized using FT-IR, XRD, FESEM, EDX, TEM and UV-Vis spectroscopy techniques. The average particle size of copper oxide nanoparticles is around 35 nm and shape of nanoparticles are spherical. Biological activity of the synthesized nanoparticles were evaluated in terms of antibacterial assessments against Staphylococcus aureus and Escherichia coli. In the following, the potential antibacterial activity against gram positive (S.aureus) and gram negative (E.coli) bacteria’s were... 

Many aroma compounds of fruit juice recovered by thermal processes like evaporation and distillation can lead to undesirable chemical changes and even their loss. Pervaporation is a promising process for the recovery of volatile organic compounds from their aqueous solutions. In the present work, pervaporation recovery of Butyl acetate as a model solution ofgrape juice aroma compoundwas evaluated with polyethersulfone (PES) and ethylvinylacetate (EVA) membranes. PES membrane generally showed better selectivity so that the separation factor at the concentration of 500 ppmand the temperature of 30°C for PES and EVA membranes, respectively, was 230.78 and 156.9. The effect of two operating...