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Energy and Economic Analysis of Vertical Farms Considering Solar Energy Utilization and CO2 Enrichment
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
Given the growth of the world's population along with the increase in the percentage of urban population by 2050, the way of responding to food consumption will change in the future. Controlled Environment Agriculture will largely account for future food supply. Vertical Farming is one of these systems. But despite the efficiency of these systems in terms of land and water and also not being affected by weather conditions, the main challenge in these systems is the consumption of energy use per unit of crop production. The cost of energy is about 25 to 40 percent of the total costs. The purpose of this study is to develop an integrated dynamic model for the determination of vertical farm...
Multi-Criteria Appraisal of Regular Bus, Bus Rapid Transit and Metro in Tehran
, M.Sc. Thesis Sharif University of Technology ; Vaziri, Manuchehr (Supervisor)
Abstract
Viewpoints of various interest groups should be addressed in any public service appraisal. Urban public transportation development and services have diverse impacts on users, operators and the community. The impacts can be characterized by a wide range of perspectives including: efficiency, effectiveness, efficacy, economic, social and environmental dimensions. Deployment of quantitative techniques, such as multicriteria decision making methods, would facilitate such a multidimensional analysis and appraisal. The objective of the study summarized herein was to shed some light on the perceived attributes pertinent to the Tehran regular transit service appraisal. The major services include...
Effect of predeformation and heat treatment conditions in the SIMA process on microstructural and mechanical properties of A319 aluminum alloy
, Article Journal of Alloys and Compounds ; Volume 468, Issue 1-2 , 2009 , Pages 130-135 ; 09258388 (ISSN) ; Khalifehzadeh, R ; Keyvan, H ; Khomamizadeh, F ; Sharif University of Technology
2009
Abstract
In this study the influences of predeformation and heat treatment conditions on stress-induced melt activating process (SIMA) of A319 aluminum alloy were investigated. At 30% of predeformation a dominant globular structure of grains was obtained. However, further increasing of the predeformation rate considerably reduced the shape factor. The holding time of 10-15 min at semi-solid temperature of 580 °C was suggested in order to prevent grain growth. Coarsening of the grains by excess time or temperature of heat treatment reduced the tensile strength of the alloy. © 2008 Elsevier B.V. All rights reserved
Durability Evaluation and Health Monitoring of Microcracked Slag-Based Geopolymer Concrete Due to Step by Step Pressure Loading
, M.Sc. Thesis Sharif University of Technology ; Ghaemian, Mohsen (Supervisor) ; Toufigh, Vahab (Co-Supervisor)
Abstract
The goal of this research is to study the effect of local microcracking due to step by step pressure loading on the durability properties of geopolymer concrete. To better understand the behavior of GGBS-based GPC under different pressure stress levels, some experiments such as water permeability and water absorption conducted on the samples at each state of damage. Also, non-destructive tests such as ultrasonic waveform and pulse velocity (UPV) was used to quantify the extent of damage at each step. GGBFS and a blend of sodium silicate solution and 10 molar sodium hydroxide solution with SSSH⁄ ratio of 2 were used for production of GPC samples. GPC, OGPC and OPC samples with water to binder...