Sharif Digital Repository

Stock return is usually considered to be affected by firm's financial ratios as well as economic variables. Fundamental method assume that stock returns is not solely related to the stock market. Most result come from the company condition, industry situation and whole economy. In this paper, this relationship between stock return and fundamentals is studied using the data for 22 pharmaceutical companies in Tehran Stock Exchange over a 7 year period, and effective factors on stock return are investigated. Because of our data natural we used panel data model from econometric methods. The results show that 80 pecent of change in stock return can be explained with 9 fundamental variables... 

This letter proposes an analytic framework for achieving an optimal solution for phasor measurement unit (PMU) placement problem. The proposed technique is on the basis of the cost/benefit analysis while long-term economic aspects and existing technical issues are simultaneously accounted for. More deployment of PMU devices would result in more reliable and secure electricity services. The reduction of system risk cost is hence recognized as the benefit associated with the development of wide-area measurement system (WAMS). The optimal number and location of PMUs are determined such that adding more PMUs is no longer beneficial. Two systems are examined to demonstrate the performance of the... 

This letter proposes an analytic framework for achieving an optimal solution for phasor measurement unit (PMU) placement problem. The proposed technique is on the basis of the cost/benefit analysis while long-term economic aspects and existing technical issues are simultaneously accounted for. More deployment of PMU devices would result in more reliable and secure electricity services. The reduction of system risk cost is hence recognized as the benefit associated with the development of wide-area measurement system (WAMS). The optimal number and location of PMUs are determined such that adding more PMUs is no longer beneficial. Two systems are examined to demonstrate the performance of the... 

One of the methods for providing private parking is to use the mechanized parking within neighborhoods or housing units that are common in today's world. But, unfortunately, due to lack of appropriate rules and technical, administrative and legal guidelines, this approach has not yet been used. Hence the necessity of investigating and formulating laws, programs and specific criteria for mechanized private parking in terms of legal, technical, traffic, urbanization aspects (location, neighborhood, architecture, building standards and national regulations, economic aspects, etc.) have been a motivation for conducting this study. In this research, after studying and investigating previous... 

The aim of this study is to show the effectiveness of prohibited operating zone. Generation scheduling is a crucial challenge in power systems especially under new environment of liberalization of electricity industry. This study is focused on the economical aspect of unit commitment problem. Since, the generating units may have certain ranges where operation is restricted based upon physical limitations of machine components or instability. Therefore, Prohibited Operating Zones (POZ) as a redundant constraint is considered, while the next load demand as a very important issue is deliberated. In this study generation scheduling of each hour is conducted by considering the next load demands... 

The promotion of the adoption of renewable energies in deprived and remote areas can be considered as an important step towards reduction of threats to the loss of biodiversity through community mobilization. One important outcome is mitigation of the deforestation processes through firewood collection. The aim is achievement of sustainable development of the forest biodiversity, awareness raising and the capacity building for execution of similar projects. The social and economical aspects and the obstacles for execution of such project were investigated and guidelines were prepared to facilitate the promotion of renewable energy in similar small communities  

In this research a mathematical model for direct oxidization of hydrogen sulfide into elemental sulfur in a fluidized bed reactor with external circulation was developed. As the catalyst is deactivated in the fluidized bed, it might be placed in a reduction tank in order to remove sulfur through heating above its dew point. The reactor model demonstrated via MATLAB software. It was shown that variations of H 2S conversion as well as; products formed were reasonable in comparison with corresponding results of a fixed bed reactor. Through analyzing results of this model, it became possible to propose the main optimized operating conditions for the process considered. These conditions included;... 

This paper proposes a hybrid heuristic optimization method based on genetic algorithm and immune systems to maximize the benefits of Distribution Network Operators (DNOs) accrued due to sizing and placement of Distributed Generation (DG) units in distribution networks. The effects of DG units in reducing the reinforcement costs and active power losses of distribution network have been investigated. In the presented method, the integration of DG units in distribution network is done considering both technical and economical aspects. The strength of the proposed method is evaluated by applying it on a small and a realistic large scale distribution network and the results are compared with... 

Application of solar energy compared to conventional gas-burning boilers for steam generation in thermal Enhanced Oil Recovery processes is a newly attended technology, which brings significant benefits to the petroleum industry through environmental and economical aspects. This technique is especially designed for the regions in which gas-burning steam generation is not viable in large scale. The objective of this study is to investigate about viability of using solar energy to generate steam instead of using conventional steam generators in a Venezuelan extra heavy oil reservoir. Limited gas production policy of the Venezuelan government is the major challenge for utilizing gas steam... 

Construction and demolition (C&D) waste dreadful impacts increasingly cause public concerns. Aiming to boost resource exploitation efficiency, circular economy is contemplated a pertinent C&D waste management practice. However, transitioning to circular economy in C&D waste management is hindered by barriers which are to be found and overcome to adeptly handle this kind of waste. In this paper 22 potential crisp barriers are identified through reviewing the seminal literature which could be categorized under three dimensions of behavioral, technical, and legal. Six experts in behavioral, technical, and legal sciences working in sustainable C&D projects were asked to rate the dimensions and... 

There is a substantial volume of mobile phone waste every year. Due to the disadvantages of traditional methods, it is necessary to look for biological processes that are more eco-friendly and economical to recover metals from e-waste. Fungi provide large amounts of organic acids and dissolve metals but using sucrose in the medium is not economical. In this paper, the main objective is to find a suitable alternative carbon substrate instead of sucrose for fungi bioleaching of Ni and Cu in printed circuit boards (PCBs) of mobile phones using Penicillium simplicissimum. Four kinds of carbon sources (including sucrose, cheese whey, sugar, and sugar cane molasses) were selected. Also, pH and... 

One of the primary factors affecting the amount of worldwide energy consumption and greenhouse gas emissions is cooking. Solar cooking is an appropriate solution because it is both inexpensive and expandable. To illustrate modern advancements and the current status of solar cooking technology, this paper presents a review of recent experimental and analytical socioeconomic studies on solar cookers. The experimental studies have been divided into three categories based on different solar cooker structures: (i) box types, (ii) concentrating types, and (iii) panel types. Next, different designs are investigated according to their direct or indirect heat transfer modes and optional equipment for... 

In the present paper, the effects of inlet fogging system on the first and second law efficiencies are investigated for a typical power plant (Shahid Rajaee) which is located near Ghazvin in Iran. Also a new function is proposed for system optimization that includes the social cost of air pollution for power generating systems. The new function is based on the first law efficiency, energy cost and the external social cost of air pollution for an operational system. Social cost of air pollution is based on the negative effects of air pollution on the health of society and environment. The economic aspect of these effects is called external social cost of air pollution. Other pollution sources... 

In this research a mathematical model for direct oxidization of hydrogen sulfide into elemental sulfur in a fluidized bed reactor with external circulation was developed. As the catalyst is deactivated in the fluidized bed, it might be placed in a reduction tank in order to remove sulfur through heating above its dew point. The reactor model demonstrated via MATLAB software. It was shown that variations of H 2S conversion as well as; products formed were reasonable in comparison with corresponding results of a fixed bed reactor. Through analyzing results of this model, it became possible to propose the main optimized operating conditions for the process considered. These conditions included;... 

The challenges of water resources sustainable development are enormous. Around the globe, the increasing use of water coupled with environmental deterioration calls for sustainable development of the limited water resources. As a significant part of the world's population still lacks access to safe water and adequate sanitation, and as global urbanization continues to increase, continuous, comprehensive, coordinated and cooperative water resources management is required for the sustainable future of urban areas. The objective of this study was to assess water resources sustainable development for selected urban areas around the world. Using centralized databases of international agencies for...