Sharif Digital Repository

A basic highway design problem is to find the most economical alignment connecting two given end points based on topography, soil conditions, socioeconomic factors and environmental impacts, while satisfying a set of design and operational constraints. The cost function complexity and numerous limitations such as highway design criteria have made this problem a NP-hard one. In this study, a swarm based searching algorithm has been applied to a three dimensional highway alignment optimization model. The spatial data has been exploited from a GIS databases using a heuristic swift approach. In addition, the majority of cost items that depend on highway design have been extended in a practical... 

As a robust and accurate classification of tumors is necessary for successful treatment of cancer, classification of DNA microarray data has been widely used in successful diagnosis of cancers and some other biological diseases. But the main challenge in classification of microarray data is the extreme asymmetry between the dimensionality of features (usually thousands or even tens of thousands of genes) and that of tissues (few hundreds of samples). Because of such curse of dimensionality, a class prediction model could be very successful in classifying one type of dataset but may fail to perform well in some other ones. Overfitting is another problem that prevents conventional learning... 

In this research, portfolio risk management methodology has been developed based on the portfolio management standard. This document is applicable as a template and standard for the organizations managing their projects in a portfolio structure since the methodology is based on portfolio standards and risk management, and it is being benefitted from their synergy. The most essential goal of portfolio management is to protect the organization against damages and to prepare it for responding to risks. In order to realize the goal of portfolio risk management, a well-developed and operational framework shall be provided. Therefore, the purpose of this study is to express the details of the... 

Roll bonding process is commonly used for the production of multilayer sheets. In the present study, using the roll bonding process, two layer sheets of copper - stainless steel were produced. In this case bonding strength was measured by peeling test at different statges and the quality of bonding was evaluated by SEM and Stereo Electron Microscope. The cross-sections of the bonding of rolled and annealed samples was investigated by optical microscopy. Also using EDAX analysis and EDS, the chemical composition of formed transition layer and the size of its interface at different temperature are measured respectively and the change in mechanical properties was investigated by tensile test... 

In the present thesis, the issue of locating end devices in the LoRa IoT network is examined using the received signal strength (RSS) approach. Recent advancements in machine learning techniques have revolutionized the localization field, enabling researchers to achieve better performance in non-line-of-sight (NLOS) and multipath interference conditions compared to traditional methods such as RSS and time difference of arrival (TDOA). This research first aims to reduce the position estimation error by appropriately scaling the received signal strength values on the public Antwerp dataset and to obtain a trained model for real-time localization of end devices. After introducing an appropriate... 

Crude oil production could cause the thermodynamic equilibrium of the crude oil to be disturbed in the well column which results in asphaltene precipitation and deposition. The thickness of the deposited material grows over time until it completely blocks the well column.Due to the hard and insoluble nature of deposited asphaltene, the two main chemical and mechanical methods are found to be more effective. It should be noted that the actual organic sediments in the piping are not pure and consist of three components: asphaltene, resin and paraffin. Therefore, it is very important to know the composition of the deposited material before selecting the appropriate chemical solvent.The samples... 

A key driver of entrepreneurial behavior is identity. Prior studies have shown that having an entrepreneur as a parent increases the likelihood of children becoming entrepreneurs by up to 60%. Accordingly, it can be argued that parents help their children construct an entrepreneurial identity within the family environment. Identity theory and identity process theory offer valuable explanations for clarifying the process of identity formation. Based on these theories, we demonstrated that entrepreneurial parents’ emotions—particularly fear of failure and passion, which stem from the enactment of their identity—can influence the centrality of entrepreneurial identity in their offspring....