Loading...
Search for:
energy-budget
0.006 seconds
Thermal structure and energy budget for alghadir reservoir, iran
, Article Water Resources ; Volume 40, Issue 6 , 2013 , Pages 621-630 ; 00978078 (ISSN) ; Sharif University of Technology
2013
Abstract
Knowing the rate of evaporation from surface water resources such as channels and reservoirs is essential for precise management of the water balance. Few detailed evaporation studies exist for small lakes or reservoirs in arid regions of the world. In this study, monthly evaporation was determined by Bowen Ratio Energy Budget technique (BREB) for Alghadir reservoir (Saveh, Iran) from 1995-2007 and compared with class-A pan. Daily data were obtained from IMO (Iran Meteorological Organization) weather station, located near the reservoir, for all of these years. Some variations have been observed on the estimated evaporation of the energy budget at different years, ranging from 151 cm for 1997...
(Comparing Empirical Methods of Evaporation in Hypersaline Lakes Utilizing Energy Balance Method (The Case of Urmia Lake,Iran
, M.Sc. Thesis Sharif University of Technology ; Tajrishy, Masoud (Supervisor)
Abstract
Evaporation is the initial process of losing water and heat from the surface of the lake. There are six well-known methods for estimating the evaporation of water from surface water including: the water balance method,the energy balance method, themass transfer methods, the combined mass transfer and energy balance method, the empirical equation and using pan evaporation. In this thesis, evaporation has been calculated with using different equations, in-site observation and remote sensing data. These results also have been compared with the results of the energy balance method. In addition, we have developed modified empirical equations of fresh water evaporation estimation with the...
Modelling useful energy demand system as derived from basic needs in the household sector
, Article Energy Efficiency ; Volume 7, Issue 5 , 2014 , Pages 903-921 ; ISSN: 1570646X ; Saboohi, Y ; Sharif University of Technology
Abstract
Inter-fuel substitution in the household sector depends on whether their target energy use is similar or not. To account for the effect of end-use application on energy demand, the concept of useful energy is utilized in which energy carriers are grouped according to their end-use applications. Useful energy is assumed as a commodity demanded to satisfy needs. Therefore, it should possess certain characteristics in accordance with the nature of basic needs. These characteristics were investigated through a two-level budgeting system with demographic variables indicating rural and urban households of Iran. The model has been applied to estimate the behavioural parameters such as income and...
Exploiting the Intrinsic Redundancy of Multicore Platforms to Achieve Low-power Fault-tolerance in Embedded Applications
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
VLSI technology scaling has resulted in the integration of a larger number of cores in a single chip in successive technology nodes, offering a great potential to realize task-level redundancy for reliability enhancement in safety-critical applications. However, since battery technology no longer advances commensurately with integration density, multi-core platforms may have limited utility in battery-powered embedded systems. In this thesis, we propose an energy-budget-aware reliability management (enBudRM) method for multi-core embedded systems featuring hybrid energy source (with renewable and non-renewable energy sources). Our method is composed of two phases. In the offline phase, we...
2D numerical simulation of density currents using the SPH projection method
, Article European Journal of Mechanics, B/Fluids ; Volume 38 , 2013 , Pages 38-46 ; 09977546 (ISSN) ; Firoozabadi, B ; Mahdinia, M ; Sharif University of Technology
2013
Abstract
Density currents (DCs) or gravity currents are driven by gravity in a fluid environment with density variation. Smoothed Particle Hydrodynamics (SPH) has been proved to have capabilities such as free surface modeling and accurate tracking of the immiscible-fluids interface that can be useful in the context of gravity currents. However, SPH applications to gravity currents have been limited to often-coarse simulations of high density-ratio currents. In this work, the SPH projection method is tried to solve currents with very low density-ratios (close to one), at a resolution, that captures the Kelvin-Helmholtz instabilities at the fluids interface. Existing implementations of the SPH...
Low-energy standby-sparing for hard real-time systems
, Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Volume 31, Issue 3 , 2012 , Pages 329-342 ; 02780070 (ISSN) ; Al Hashimi, B. M ; Eles, P ; Sharif University of Technology
Abstract
Time-redundancy techniques are commonly used in real-time systems to achieve fault tolerance without incurring high energy overhead. However, reliability requirements of hard real-time systems that are used in safety-critical applications are so stringent that time-redundancy techniques are sometimes unable to achieve them. Standby sparing as a hardware-redundancy technique can be used to meet high reliability requirements of safety-critical applications. However, conventional standby-sparing techniques are not suitable for low-energy hard real-time systems as they either impose considerable energy overheads or are not proper for hard timing constraints. In this paper we provide a technique...
Design and construction of a two-phase fluid piston engine based on the structure of fluidyne
, Article Energy ; Volume 127 , 2017 , Pages 660-670 ; 03605442 (ISSN) ; Yarahmadi, M ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Engines that extract energy from low-grade heat sources, e.g., from other processes, have received considerable attention recently. The use of Fluidyne, which is a liquid piston Stirling engine, is quite popular. Herein, we explore the use of liquid-to-vapor phase change in a Fluidyne. This provides two considerable differentiators; (1) exploitation of very low temperature difference ΔT≈30 K, and (2) relatively low temperature ΔT≈330 K heat sources, for producing mechanical work, and thus electrical energy. The influence of three operating parameters, i.e., input heat flux, working fluid, and filling ratio, on the performance of the engine was characterized. Their optimum values, which yield...