Observer-Dependent TIN Simplification Based on Visibility Graph

, M.Sc. Thesis Sharif University of Technology Behrooznia, Nastaran (Author) ; Zarei, Alireza (Supervisor)

Abstract

Geographical environments can be modeled through the medium of TINs, in which some discrete points are sampled as vertices, and the union of polygonal faces, particularly triangles, constitutes its surface. As regards the two-dimensional space, the TIN boundary is an x-monotone path and we focus on this case. If the number of vertices is too large to be stored or some sampled points should be removed due to a lack of vital information, the necessity of TIN simplification arises. On top of this situation, if a point observer locates on or above the TIN, the points visible to the observer have more priorities to be considered in the simplified TIN. For example, human eyes can see the closer or...

Assessment of Existing Offshore Platforms for In-Place Conditions

, M.Sc. Thesis Sharif University of Technology Bassamzadeh, Nastaran Sadat (Author) ; Golafshani, Ali Akbar (Supervisor)

Abstract

Assessment of existing jacket type offshore platforms in Persian Gulf for life extension is of great importance in the field of offshore platforms in recent years. The main question to answer is whether an existing platform is safe enough to be used beyond the design life. Evaluation of existing jacket type offshore platforms under extreme environmental (wave) loading in Persian Gulf is a part of this major assessment. Two general approaches exist in this context, deterministic and probabilistic assessment. In this thesis, a new probabilistic method (reliability analysis) to assess offshore structures under environmental loading (extreme wave) is introduced. This method is a...

Growth of Perovskite Film based on Lead Iodide by Controlling Deposition Parameters for Solar Cells Application

, M.Sc. Thesis Sharif University of Technology Tafazoli, Saeedeh (Author) ; Mohammadi, Mohammad Reza (Supervisor) ; Seyed Reihani, Morteza (Supervisor) ; Riahi, Nastaran (Co-Advisor)

Abstract

Perovskite solar cells, with high efficiency operation, have been candidated as a cost-effective and environmentally friendly technology. Despite the great progress, there are some primarily issues remained regarding to the perovskite film and its fabrication methods. A very common perovskite cell structure is FTO/TiO2/CH3NH3PbI3/Spiro-OMeTAD/Au. Although, this structure has some advantages, lack of full surface coverage of perovskite film leads researchers to put much effort on finding other constructions. This surface inhomogeneity reduces the amount of light absorption and therefore efficiency. One way to produce a complete and uniform film is applying mixed-halide composition; such as...

Solvent Engineering for Preparation of Perovskite Film based on Lead Iodide for Solar Cells Applications

, M.Sc. Thesis Sharif University of Technology Timasi, Nazanin (Author) ; Seyed Reyhani, Morteza (Supervisor) ; Mohammadi, Mohammad Reza (Supervisor) ; Riahi Noori, Nastaran (Co-Advisor)

Abstract

The microstructure, morphology and quality of the perovskite organic-inorganic layer as an absorber layer in perovskite solar cells has a significant role on the efficiency and energy conversion of the device. Different solvent engineering methods have been employed to prepare the perovskite layer with the desired properties and thier reproducibility have been studied. Herein, we applied a two-step solution approach by solvent engineering method, using solvents such as isopropyl alcohol, acetone and thier mixture, for preparation of lead iodide films. Moreover, their metallurgical and photovoltaic properties were investigated. The impact of solvent engineering, using solvents such as...