Evaluation of tunnels and water channels tsniaga in the earthquake

Evaluation of tunnels and water channels tsniaga in the earthquake

… Download …


Part of #Evaluation of tunnels and water channels tsniaga in the earthquake# :

Publishing year : 2012

Conference : Fourth International Conference on Reinforcement

Number of pages : 8

Abstract: Today, due to the increasing tendency to use underground transportation networks, especially in urban areas, a number of subway tributaries in seismic regions have been created or studied, in which their failure against earthquake shocks can lead to humanitarian catastrophe and significant economic losses. Water tunnels and canals are one of the structures whose seismic behavior varies with many different types of rocks. The reason for these magnitudes is the size of their dimension in comparison with other dimensions, and secondly, their placement in the ground is completely buried in tunnels or half-buried channels. Be in general Historically, such structures are less damaged than earthquake building structures, which seem to have higher levels of safety than surface structures. Nevertheless, there have been numerous reports, especially in recent decades of earthquakes about the failures of these structures. Indicating that damage and damage were possible and that seismic considerations should be considered in the design and implementation aspects.

Drought and its effect on vegetation, comparison of NDVI for drought and non-drought years related to Land use classifications

Drought and its effect on vegetation, comparison of NDVI for drought and non-drought years related to Land use classifications

… Download …


Part of #Drought and its effect on vegetation, comparison of NDVI for drought and non-drought years related to Land use classifications# :

Publishing year : 2012

Conference : 7th International Conference on Science and Technology

Number of pages : 8

Abstract: The purpose of this study is to analyze the effects of drought on various land use types. This study uses a combination of remote sensing data, field observations and information from local people to analyze the effects of drought on various land use changes for 2 years in 1999 and 2004 in Isfahan. Imagery was selected for both drought and non-drought conditions based on precipitation data. The Normalized Difference Vegetation Index (NDVI) was then calculated for both images in order to detect the amount of change within the study area. The NDVI images were then analyzed for land use classification to determine which classification was most susceptible to dryness in terms of reduced NDVI values. Overall, there was a decrease in NDVI values for the drought conditions as expected. The results of this experiment indicated that the rangeland classification had the highest percentage change between the two NDVI images; Mean NDVI value change from 0.199 to 0.895 resulting in a 63.6 percent change due to the effects of the drying. Therefore the rangeland was the most effected land classification; Однако в цьому класі містяться декілька факторів, включаючи випасання пасовищ, заморозки та збирання урожаю, які могли б переконувати результати.

Moment-Height Stability Measure for Wheeled Mobile Manipulators

Moment-Height Stability Measure for Wheeled Mobile Manipulators

… Download …


Part of #Moment-Height Stability Measure for Wheeled Mobile Manipulators# :

Publishing year : 2006

Conference : Fourteenth Annual Conference of Mechanical Engineering

Number of pages : 7

Abstract: Tipping-over is one of the most important problems in mobile manipulators, especially when manipulating heavy objects, also during maneuvers in unknown environment or in rugged terrains. Therefore, the estimation and evaluation of dynamic stability with a suitable easy-computed measure throughout the motion of such systems is a challenging task. In this study, a new effective tip-over stability measure called the Moment-Height Stability (MHS) measure is presented for a wheeled mobile manipulator. The suggested MHS measure can be effectively used for both legged robots and mobile manipulators. Finally, two case studies are presented to demonstrate the new MHS measure performance compared to ZMP measure results. The obtained simulation results show the merits of the new proposed MHS measure in terms of prediction of the exact time of the occurrence of instability without additional precautions which may limit the maneuverability of the system and its operation.

The Comparative Effect of Individually created and collaboratively created Concept Maps on EFL Learners’ Essay Writing

The Comparative Effect of Individually created and collaboratively created Concept Maps on EFL Learners’ Essay Writing

… Download …


Part of #The Comparative Effect of Individually created and collaboratively created Concept Maps on EFL Learners’ Essay Writing# :

Publishing year : 2014

Conference : Second National Conference on Applied Research in English Language Studies

Number of pages : 10

Abstract: The present study was an attempt to investigate the comparative effects of individually created and collaboratively created Concept Maps on EFL learners' essay writing. To accomplish the purpose of this study, 60 male and female learners from a total of 90 intermediate learners at Kishe Mehr Language School in Tehran were selected based on their performance on a pilot PET. The 60 learners were thus divided into two groups and each of the groups was taught to write through one of two forms of concept mapping, namely, individually created and collaboratively created. At the end of the study, the participants in both groups were given a post posttest. The design of this study was quasi-experimental and posttest only and ANCOVA was used which led to the rejection of the null hypothesis. Thus, individually constructed concept maps proved to be more effective than collaboratively created concept maps on intermediate EFL learners' essay writing. The finding of this study has implications for EFL teachers, teacher educators, and material developers.

Modified a New Multi Objective based Optimization of Capacitor Banks using Genetic algorithm

Modified a New Multi Objective based Optimization of Capacitor Banks using Genetic algorithm

… Download …


Part of #Modified a New Multi Objective based Optimization of Capacitor Banks using Genetic algorithm# :

Publishing year : 2015

Conference : International Conference on Engineering, Science and Technology

Number of pages : 31

Abstract: Distributed Generators units and shunt capacitors are allocated and optimally and simultaneously for line loss reduction, voltage profile improvement and reliability increase of power system. The objective function, which includes power losses (active and reactive), voltage profile and reliability indices, is maximized using a genetic algorithm. Power system operating limits are considered as constraints. The problem of optimal distributed generation and capacitor size and placement is solved for a 9-buss test system and the results of applying the proposed method illustrate the best answer found by optimizing both DGs and capacitors in distribution networks

Resource Allocation in Decode-and-Forward Relaying Systems Based on OFDM

Resource Allocation in Decode-and-Forward Relaying Systems Based on OFDM

… Download …


Part of #Resource Allocation in Decode-and-Forward Relaying Systems Based on OFDM# :

Publishing year : 2012

Conference : 20th Iranian Conference on Electrical Engineering

Number of pages : 6

Abstract: In this paper, we investigate resource allocation algorithms for Orthogonal Frequency Division Multiplexing (OFDM) based dual hop systems including a source, multiple relays, and multiple destinations, and utilizing Decode-and-Forwarded (DF) relaying. The main objective is to maximize the spectral efficiency under the total power constraint. We first propose an algorithm that simultaneously allocates transmission power and transmission time used by each hop in every time frame. Then we propose a more tractable algorithm which decomposes the original problem in two subproblems. The first subproblem is to solve the optimization problem for a given value of the transmission time used by each hop, and the second subproblem is tocompute the value of transmission time. The discussed algorithms are also compared with each other and with other resourceallocation schemes. Simulation results are also provided, which verify performance improvements by adopting the proposed algorithms.

Solving optimal chiller loading by PSO method

Solving optimal chiller loading by PSO method

… Download …


Part of #Solving optimal chiller loading by PSO method# :

Publishing year : 2008

Conference : Sixteenth Iranian Conference on Electrical Engineering

Number of pages : 6

Abstract: In cities located in the subtropical regions, chillers are commonly used to cool commercial buildings almost a year, which accounts for considerable electricity consumption in the long term. This paper investigates the optimal chiller loading (OCL) problem by using the genetic algorithm and particle swarm optimization (PSO) method and calculates the optimal answer for this problem and attempts to compare these two methods in solving this problem. Implementation results show that in solving this problem the PSO method has better answers.

A Modified Hybrid IWO/PSO Algorithm for Fast and Global Optimization

A Modified Hybrid IWO/PSO Algorithm for Fast and Global Optimization

… Download …


Part of #A Modified Hybrid IWO/PSO Algorithm for Fast and Global Optimization# :

Publishing year : 2012

Conference : International Conference on Nonlinear Modeling and Optimization

Number of pages : 6

Abstract: This paper presents a comparison of the results of the modified Hybrid IWO / PSO algorithm for fast and global optimization. The IWO / PSO algorithm originates from Invasive Weed Optimization (IWO) and Particle Swarm Optimization (PSO). The efficiency of this algorithm, both in the case of the speed of convergence and the optimality of the results, is compared with IWO, PSO, and IWO / PSO through a number of common multi-dimensional benchmark functions. Experimental results indicate that the proposed approach is more competitive than other algorithms such as IWO, PSO, and Hybrid IWO / PSO

Investigation of the laboratory models scales in the analysis of the buried pipeline behaviors

Investigation of the laboratory models scales in the analysis of the buried pipeline behaviors

… Download …


Part of #Investigation of the laboratory models scales in the analysis of the buried pipeline behaviors# :

Publishing year : 2008

Conference : Fourth National Congress on Civil Engineering

Number of pages : 8

Abstract: For the analysis of the buried pipelines, the behavior and recognition of the interactions between the buried pipeline and the surrounded soil and the real simulation and for the recognition of the sensitivity of the parameters are necessary in some experiments. Generally, researchers would use small laboratory models and in a laboratory site with dimensional scales that included variations of dimensional scales, and some times the combination of small models and site models is considered for analyzing behavioral patterns. For the avoidance of these calculation problems, it was usually considered in the unit scale and because most scientific research is important parameter efficiency, so the labor models that are considered to be power should prepare real conditions. In these articles, besides introducing laboratory models of underground pipelines, site models, included site models and laboratory models, variation gages model would be an analysis according to type of load, phenomenon and purpose.