Sharif Digital Repository

Condensation from a gaseous phase is a common method for the fabrication of metallic nanoparticles. Electromagnetic induction furnaces are the most common equipment used for this method. Since the sample doesn’t touch any foreign object, this method is one of very few ways to synthesize ultrapure nanoparticles. However, a major setback of this method is its low production rate.One of the only workarounds to this issue is to increase the melt’s surface area so as to present a larger surface for evaporation. In the common setup for this furnace the molten sample takes on a spherical shape which unfortunately holds the lowest surface to volume ration of any shape. The endeavor in this study has... 

According to the principles of the country 20-year outlook charter Iran as a developing nation should be ranked first in economic, scientific and technological status in the region. Productivity improvement in all fields is one of the key essentials for realization of stable economic growth. Construction industry in developing countries contributes a major share of gross domestic product (GDP). It has a crucial bearing on economic growth, therefore enhancement of performance indicators in this industry will result in economic development of the country. This research project has offered a pattern for measuring and analyzing labor and machinery productivity in large scale construction. This... 

Product Line Engineering (PLE) is a well-established discipline in software engineering, and has gained widespread adoption in industry. Software product lines are considered an efficient means for mass production of software systems, and many companies have based their software development processes on PLE principles and practices.
Situational Method Engineering (SME) has so far been mainly concerned with metamodels and method chunk repositories; through using these means, methodologies are constructed or extended to address the specific requirements of a software development project. A recent development in SME is the introduction of “Process” Line Engineering, which promises new... 

By far, the most expensive part of the production optimization process is the evaluation of the objective function because this requires computationally expensive reservoir simulations to be performed.One way to reduce this high computational cost isby using surrogates or proxies for the reservoir simulator. There are different methods for constructing a surrogate that their aims are mimicking the reservoir behavior with high accuracy and low computational cost. In reservoir engineering surrogate modeling has been used for the problem of well placement optimization,while in the context of production optimization it has not yet been investigated in the literature. Moreover, most of surrogate... 

The main approach of this thesis is to study the performance and efficiency of agricultural biomass derived extractive phases in sample preparation methods. In this regard, different types of agricultural biomasses and various important factors in the production of biochar from biomass were studied by two physical and chemical methods. Accordingly, different types of biochars have been made and applied in different extraction setups along with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and gas chromatography-electron capture (GC-ECD) to detect agricultural pesticides. Also, validated developed methods were used to investigate the safety of some highly... 

Export subsidy is one of the important issues among the various trade policies in developing countries. For more than a century, various effects of export subsidies have been studied in literature and different results have been presented. In this study, the effect of export subsidy of several agricultural products on their weight and export price has been investigated. In 2015 and 2016, respectively, potatoes and five groups of dairy products were subject to cash subsidies. The results of the research show that the growth of potato’s weight has been affected by the subsidy and has increased. Also, according to the results, the effects of the decrease in export price growth can be seen, and... 

In this study, the polysulfon ultrafilteration membranes were prepared and applied to concentrate the Lipase enzymes produced in the laboratory and the commercial enzymes of Novozymes Company. Using Design Expert software. The effect of membrane preparation conditions including polysulfone and polyvinylpyrrolidone concentration and the solvent type were investigated. The prepared membranes were characterized by measuring of distilled water flux, enzyme liquor flux, and enzyme activity in permeate and the Retentate flows. The results showed that increasing of polysulfone concentration reduced the flux of distilled water and enzyme activity in permeate and enhanced the enzyme activity in the... 

Productivity is the effective usage of input or resources for production or output. Input (including Energy, raw materials, capital and work force), which is being used for output (including final products or services performed by an organization). Productivity, increases gross domestic product and competitiveness, and improves level of living. Firms and related management levels play the main role in improving productivity. Using productivity cycle management brings the productivity to improve as a permanent process, specifies the rout for productivity and prepares the ground. The most important step in productivity cycle (PDCA) is the measurement of productivity. In this research several... 

Due to the widespread use of pesticides and their harmful effects on humans and wildlife, monitoring their residual amounts in crops is critically essential but still challenging regarding the development of high-throughput approaches. Herein, a colorimetric sensor array has been proposed for discrimination and identification of triazole fungicides using monometallic and bimetallic silver and gold nanoparticles. Aggregation-induced behavior of AgNPs, AuNPs and Au-AgNPs in the presence of four triazole fungicides produced a fingerprint response pattern for each analyte. Pattern recognition methods, including linear discriminant analysis (LDA) and hierarchical cluster analysis, have been... 

In this research Feature Recognition technique for the 2.5D parts in Boundr Representation ( B-Rep ) solid modeling was used.
This method uses DXF file and convert the wire model to B-rep model to recognize the Face, Inner loop and Outer loop. The algorithm of recognition the Face, Inner loop,.. were prepared and a software (visual basic) was developed.In a case study a part with a protrusion, depression and a hole was recognized and then the effect of this method in comparison to the traditional methods on productivity was surveyed  

Although technological specialization has been recognized as a stimulating factor of international trade (Ricardian theory), new approaches emphasize the endogeneity of technological heterogeneity across countries. Following them, we proceed to examine the effect of free trade on technological differences among 20 OECD members during 1996-2008. We first use the model of Eaton and Kortum (2002) to obtain an annual estimate of technological heterogeneity within the OECD group. We then analyze the behavior of this index facing international trade statistics in the same period. The results show that the OECD countries have been experienced a technological convergence, thanks to a boost in the... 

Sanctions are one of the most important variables influencing Iran's domestic and international decision-making and have had many effects on Iran's economy and politics in recent years. Iran's ability to influence the oil market and harm the interests of the sanctioning countries in this market raises the question of whether such a capability could affect the outcome of sanctions and lead to the withdrawal of those sanctioning countries. A theoretical examination of the issue of sanctions using game theory shows that if the sanctioned country is not able to retaliate in areas other than the disputed issue, the sanctions game may not reach an equilibrium in which the sanctions are lifted but... 

As a strategically critical stage of new product development, launch process has attracted a lot of attention. A lot of study has been done about launch and its effect on product performance.The objective of this thesis is to gain more understanding about new product launch and the way it is executed. The aim is to create a process description of product launch; how the process begins and how different phases follow each other until the introduction of new product. The main research problem is how new product launch can be described as a marketing-focused process. Further, the research problem is answered through literature review and empirical case study research. The literature review... 

Economics is the science of using scarce resources, which helps to identify the optimal use of economic resources. Enhancement of productivity leads more efficient use of resources in economics sectors. Identification of ways and means of improving productivity is an important policy issue which requires an analysis of the effects of determinants of productivity. In the present research work, Total Factor Productivity (TFP) has been econometrically estimated; based on production function theory. Application of this concept indicates that the elasticities of total value-added (i.e. GDP minus oil rents) with respect to physical capital and labor are 0.8 and 0.2 respectively. It is further... 

In recent decades, rapid growth in the utilization of energy resources has led to using a system of combined power, heating and cooling due to their high efficiency. Losses of electrical power transmission and distribution networks are also another reason to emphasize using the combined production systems. Today, the use of small scale combined production systems at the same time, competitive with electricity generated from renewable energy technologies have also emerged. The present study was undertaken to answer questions on the topic of disrict heating and cooling system design with power that can be occur. For this purpose, first the governing mathematical equations are expressed and... 

World environmental concerns sharp increase in necessity of using energy in comparison with permanent progress in the field of renewal energy technologies causes modern forms of energy sources which can be used by public. This project studies the increasing influence of the wind power in power systems and also designing and exploiting techniques of local saving energy systems. For this purpose, models and possibilities in order to anticipate the operation of wind farm which is connected to grid by saving energy is described. In this project, the operation of compound system components which is totally a combination of three systems is being studied. The considered compound systems consist of... 

Facing the two challenges of the recession and rising requirement to reduce carbon emissions have led countries around the world to look for ways to promote economic productivity and reduce greenhouse gas emissions. In the meantime, the appearance of renewable energies has the potential to grow and diversify the economy, in addition to providing an effective solution to meet the growing demand for energy. The impact of development of the renewables industry on the economy for each country and each type of renewables can be examined separately. The purpose of this study is to evaluate the development role of wind energy industry as the motive engine of industry and specifically answer two... 

Regarding decreasing resources of fossil fuels and their increasing costs in addition to their environmental pollutions, today, producing bio fuels from wastes such as lignocellulosic materials is of great interest. A fundamental stage in conversion of lignocellulosic materials into bio fuels, such as bio ethanol, is the enzymatic hydrolysis of these materials to produce reducing sugars. Researches have shown high costs of this stage. Optimization of enzymatic hydrolysisconditions is a major step in economization of this process.In this work corn hull is used to produce glucose. Corn hull is a kind of lignocellulosic material that due to high carbohydrate content is used as substrate. Our... 

There are a lot of Fractured reservoirs around the world that have large portion of oil production. These reservoirs have complex structure and fractures have important role in production but the remaining oil in matrix causes that the oil recovery decreases. One of the most important factors in these reservois are wettability. Because most of the fractured reservoirs are oil wet and water injection process in these reservoirs are not effective and chemical EOR methods such as surfactant flooding method is used. Surfactant improve oil recovery by two reasons: 1- reduction of interfacial tension between oil and water . 2-Wettability alteration of matrix. The porpose of this project is... 

Isfahan Zirconium Production Plant (ZPP) is one of the most important plants in the nuclear industry of Islamic Republic of Iran. The wastewater of this plant contains high values of Sodium, Chloride, Nitrate and low values of Calcium, Magnesium, Zinc and Zirconium ions. Its release has been banned by international and national law because of the dangers and toxicity of its ions for the environment and living organisms. Therefore, its refinement as a compensation of Iran’s water resources in agriculture and drinking water has received a major consideration. Among the common methods to removal of these ions, membrane process method is selected due to it's major benefits such as not producing...