Sharif Digital Repository

The purpose of this study is to investigate the effect of consecutive earthquakes by considering different levels of structural damage intensity index. The cumulative damage of structures caused by the sequence of main earthquake and aftershock is a combination of the initial damage caused by the main earthquake and the increased damage caused by the aftershock. The evaluation process of the main earthquake and aftershock is divided into two parts: evaluation of the fragility of the main earthquake and evaluation of the fragility due to the aftershock. This investigation was carried out using a 4-story steel building with special moment resisting frame. The results for the case of only the... 

Application of the advanced control techniques and information technology in the biomedical engineering have been the focal point of the research communities in biomedical engineering due to the rapid growth of the nonlinear control theories along with the computer hardware. In this work the application of differential geometry and globally linearizing control has been applied to efficiently control the first phase of HIV disease based on the HIV infection model proposed in the literature. All the efforts have been in the way to obtain a suitable scenario of drug administration to suppress and control the infection. In the proposed scenario, drug administration is time dependant and... 

Variation in value and initial cost of construction contracts in many cases lead to considerably increasing the finalized price. These increases are sometimes so big enough that the 25 percent of limitation which could be added to contracts couldn't make them to be finalized and exploitable, so the necessity of a new contract sometimes up to 100 percent or even up to 200 percent of initial cost for completing the same project is inevitable. Although in some specific and rare cases we couldn't avoidance from these changes, but observing the growth of these changes in public construction projects of Iran increase the requirement of special attention in order to find the main causes, prevention... 

A large number of bridges in Iran are deteriorating under long and heavy traffic loadings, while getting closer to the end of their design life time. Therefore, many of them have been exhibiting various problems such as excessive vibration or large deflection under the normal service loadings. So, mitigating traffic-induced bridge vibration and damages is necessary to extend their efficient period of serviceability. On the other hand, application of active and passive control devices in structural retrofitting have absorbed the attention of many engineers and researchers. In this work, the performance of an active control system made of piezoelectric actuators is investigated in reducing the... 

The main goal of the current building design codes is to protect life safety, and generally, they do not directly address other societal, economic, etc., concerns regarding earthquakes. However, recent earthquakes around the world have shown that the effects of earthquakes' damages and losses can go beyond life-safety concerns. This observation has led many renowned scholars, organizations, and agencies to state the need to change the current design codes. In this regard, this thesis investigates the basis of setting the seismic design requirements and suggests a method in this respect. The study consists of two main parts. Part I (theory and design methodology) discusses some theoretical... 

With the development of technology and growing interest in using high performance and low price products, Wireless Sensor Networks (WSNs) are being dramatically deployed as an emerging technology. The main concern in WSNs is energy consumption that has an effect on sensor’s life time. In order to minimize the energy consumption, Data aggregation, which obtains aggregated values from WSNs, is an important functionality but yet time consuming. On the other hands, Emerging applications of Wireless Sensor Networks (WSNs) such as real-time detection of events need high-rate data collection, which is now an important challenge in WSNs. Multi-channel communication is one of the efficient methods to... 

The main purpose of this study is to evaluate the linkage between two constructs about teamwork activities. One of them is "self-leadership in teamwork", the extent to which a person could control and manage his thoughts and activities in teamwork. The other is "shared leadership orientation", which is about orientation of people to contribute in leadership processes. This linkage evaluated with consideration of "self-efficacy in shared leadership" as a moderator.
Questionnaires of self-leadership in teamwork and self-efficacy in shared leadership elicited from literature with a little change and shared leadership questionnaire developed in another study by the author.Questionnaires... 

Women are going to play more important roles in the economy of most countries including Iran. Hence, since the number of entrepreneurs among women is increasing, identifying characteristics and other factors that cause these group to be successful, is a critical issue. Studies show that entrepreneurs, especially women entrepreneurs, face numerous problems in their career. These problems are especially more demanding in societies with unique cultural attributes. Therefore, applying personal and managerial solutions in order to overcome these problems are necessary. On the other hand, researchers believe that one of the most effective and beneficial concepts helping entrepreneurs in their... 

The present study was performed aiming to identify the ethical dilemmas human resource managers confront with in Iranian project-based organizations as well as to trace out the underlying causes. “Ethical dilemma” refers to a decision making situation in which ethical considerations render all the alternatives inapt, thence making the decision making process ethically complex. First of all, a theoretical framework was developed based on the preceding research; then, the study was further conducted utilizing a qualitative research method with an exploratory approach. The data were collected using in-depth interviews and analysed using the theme analysis method. The corresponding interviewees... 

Using Distributed leadership framework while studying the leadership phenomena in teams, especially in educational environment, has received more attention by scholars in these years. Although the results of these researches indicated positive consequences mostly, the need for exploratory studies to identify situational and contextual factors in distributed leadership effectiveness has been mentioned. In other words, it has been suggested that the effectiveness of distributed leadership in teams may be affected by situational and contextual factors. In the current multiple case study, after the initial study of leadership and its functions in some schools of Sharif University of Technology,... 

The influence mechanisms of executive/non-executive board compostion on board’s attribution style have been explored. In two case studies, I have examined boards’ causal interpretation about a critical incident which had a significant impact on firm performance. A qualitative research approach has been taken in the case studies. Data was gathered through semi-structured interviews with all board members and was analyzied with the theme analysis method. According to the results, board of directors’ collective attribution formation process can be devided into three stages of members’ expression of information and facts at board meetings, forming the individual judgements of members and at... 

Career Orientations or career choices, can be affected by internal and external factors. External factors are the environmental conditions that the reward and the attractiveness of selecting a career choice are dependent to them. Internal factors include the needs of oneself from his/her job, his/her beliefs and his/her skills and competencies about the job. In this research the internal antecedents of managerial and technical orientations between programmers have been identified. On the other hand the perception of people about the compensation system as an external factor which can affect the mentioned relationships, have been analyzed. It seems that this is the first research which career...