Sharif Digital Repository

One of the main geotechnical phenomena that causes severe damage during earthquake is liquefaction. This incident occurs due to the undrained behavior of loose sandy soils. In this occurrence, the interaction between the solid and liquid phases in a cyclic motion leads to an increase in pore water pressure and a decrease in interactive forces (effective forces) between grains in the solid grains. Therefore, shear strength decreases. Different aspects of the aforementioned phenomenon is investigated, namely, field, laboratory, and numerical; nevertheless, the study is largely focused on the numerical modelling. Most studies in this field are carried out on a one-layer saturated sand. However,... 

Fountain codes enable wireless networks to adapt their transmission rates to the state of the channels, without the need for channel state information (CSI) at the transmitters. According to the following properties of rateless codes, ever increasing parity generation, mutual information receiver, single bit feedback, and information combining receiver, they are good choice for relay networks. In this research, the design of rateless codes for wireless relay networks has been studied. Cross layer issues should be seriously considered when using rateless codes in the packet level. One cross-layer scheme has been developed in this thesis and analysis show that the performance of the proposed... 

Supply chain problems consist of a large number of issues. One of the key problem in this area is supplier selection in supply chain. Several criteria must be considered in the supplier selection. So, multi criteria decision making approach, neural network, mathematical programming and etc. are used for solving this problems. In most of these problems, supplier selection is done according to the buyer’s objectives.
So far, several methods are provided for supplier selection problem. In majority of them, supplier selection problem is surveyed from buyer’s viewpoint and in those have only been considered the buyer’s benefit maximization that will not necessarily lead to optimal condition... 

To have a deeper understanding of Hydraulic fracturing operation, in this study four important parts in this field was developed and simulated. In the first part, continuity and momentum equations for a single phase flow in a propagating penny-shaped fracture inside an impermeable matrix was revisited based on a fixed coordinate system. Its correctness was validated against experimental data and its features were compared with the well-known lubrication theory in analytical form. The new derived continuity equation caused the fracture tip to have a positive and finite pressure while, the conventional model predicted negative infinity for that. In the second part, Finite Volume method was... 

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... 

Voluntary turnover has direct and indirect expenses for organizations and for this purpose; it has one of the richest literatures in academic works. Due to the especial role of knowledge workers in organizations, these expenses in knowledge-based organizations are more important and more costly than that of other organizations. One of the latest theories in the field of voluntarily turnover was introduced by Lee and Mitchell (1994) that was named “Unfolding Model of Turnover” to describe the process of decision of voluntary turnover. This theory is distinguished from its similar theories from two main aspects: First, they introduced new elements like shock. Second, they introduced... 

The measure of success in a company is determined by a high performing workforce that demonstrates the competencies necessary to drive the business success, while meeting the organization's strategic goals. This is where competency-based human resource management becomes important. The main factor contributing to the above noted area is the identification of core competencies. There has been a lot of research in this area during the past few years. Each research demonstrates an approach for the development of critical human resource competency models in an organization. In order to determine the foregoing competency model, the early studies in this area have been focused on the distinction... 

The goal of this study was to realize how the younger generation's perceptions of the authenticity of senior managers in knowledge-based firms affects the components of their employer brand on social media. For this reason, the perceptions of managers' authenticity from the perspective of the younger generation on Instagram, as an example of social networks, was investigated in the first stage of the study. The mechanisms of effectiveness of the identified components of authenticity are sought in the second step, in shaping the components of the manager's organization's employer brand. To attain the research goal, an exploratory approach was taken conducted, and a qualitative research method... 

This research explores the impacts of the telework initiated by the outbreak of COVID-19, which is being called “emergent telework” in this research, on psychological well-being of teleworkers. As for the nature of emergent telework which is a new and unique phenomenon, a qualitative research is conducted. In order to do so, 15 in-depth interviews were held with employees from product teams of 11 organizations, and the interviews were analyzed using thematic analysis. General conditions of teleworking are identified in two categories named as “not working adjacent to coworkers” and “being away from the physical environment of the workplace”. Emergent telework, alongside the general... 

In this research study, the reciprocal relationship between Emergent States and Team Processes has been analyzed in boards of directors, by using case study method with semi-structured interview as the method of data collection and thematic analysis as the method of data analysis. This research was conducted on the companies which are active in Information Technology industries, their size is in the range of SMEs, and have passed the early startup stage and an external investor has joined the board. After thematic analysis, narrating each case’s story, and theoretical analysis on each case, the obtained results are demonstrated with discussion on both cases, introducing a theoretical model,...