Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Search Results: 1 - 10 of 1205 matches for " Ardeshir Ahmadi "
All listed articles are free for downloading (OA Articles)
Page 1 /1205
Display every page Item
Game Theory Applications in a Water Distribution Problem  [PDF]
Ardeshir Ahmadi, Raquel Salazar Moreno
Journal of Water Resource and Protection (JWARP) , 2013, DOI: 10.4236/jwarp.2013.51011

A water distribution problem in the Mexican Valley is modeled first as a three-person noncooperative game. Each player has a five-dimensional strategy vector, the strategy sets are defined by 15 linear constraints, and the three payoff functions are also linear. A nonlinear optimization problem is first formulated to obtain the Nash equilibrium based on the Kuhn-Tucker conditions, and then, duality theorem is used to develop a computational procedure. The problem can also be considered as a conflict between the three players. The non-symmetric Nash bargaining solution is suggested to find the solution. Multiobjective programming is an alternative solution concept, when the water supply of the three players are the objectives, and the water authority is considered to be the decision maker. The optimal water distribution strategies are determined by using these solution concepts and methods.

Ardeshir Ghavamzadeh,& Fereydune Ahmadi,&Mohammad Jahani
Acta Medica Iranica , 1993,
Abstract: This study was undertaken to assess the effectiveness of 5-FU plus epirubicin in the treatment of the advanced gastric cancer. For this purpose, 22 patients with no previous treatment were studied. All of the patients were unoperable or metastatic. Follow up checking continued for 24 months. Our selected therapeutic regimen consisted of a combination of 500 mg/m2 5-FU dialy for five days, and 75 mg/m2 epirubicin for one day. The response rate in this study was 47.4% and the mean survival rate was 9.7 months. By far, the most common complication was gastrointestinal disturbances and no carditoxicity was seen. Having presented the results of this study and comparing it with the other therapeutic regimens like FAM combination, this selected two drug combination seems to be a useful therapeutic protocol.
Application of Self-Organizing Map for Exploration of REEs’ Deposition  [PDF]
Mohammadali Sarparandeh, Ardeshir Hezarkhani
Open Journal of Geology (OJG) , 2016, DOI: 10.4236/ojg.2016.67045
Abstract: Varieties of approaches and algorithms have been presented to identify the distribution of elements. Previous researches based on the type of problem, categorized their data in proper clusters or classes. This means that the process of solution could be supervised or unsupervised. In cases, where there is no idea about dependency of samples to specific groups, clustering methods (unsupervised) are applied. About geochemistry data, since various elements are involved, in addition to the complex nature of geochemical data, clustering algorithms would be useful for recognition of elements distribution. In this paper, Self-Organizing Map (SOM) algorithm, as an unsupervised method, is applied for clustering samples based on REEs contents. For this reason the Choghart Fe-REE deposit (Bafq district, central Iran), was selected as study area and dataset was a collection of 112 lithology samples that were assayed with laboratory tests such as ICP-MS and XRF analysis. In this study, input vectors include 19 features which are coordinates x, y, z and concentrations of REEs as well as the concentration of Phosphate (P2O5) since the apatite is the main source of REEs in this particular research. Four clusters were determined as an optimal number of clusters using silhouette criterion as well as k-means clustering method and SOM. Therefore, using self-organizing map, study area was subdivided in four zones. These four zones can be described as phosphate type, albitofyre type, metasomatic and phosphorus iron ore, and Iron Ore type. Phosphate type is the most prone to rare earth elements. Eventually, results were validated with laboratory analysis.
Delineation of Geochemical Anomalies Based on Cu by the Boxplot as an Exploratory Data Analysis (EDA) Method and Concentration-Volume (C-V) Fractal Modeling in Mesgaran Mining Area, Eastern Iran  [PDF]
Mohammadreza Agharezaei, Ardeshir Hezarkhani
Open Journal of Geology (OJG) , 2016, DOI: 10.4236/ojg.2016.610093
Abstract: The target in this investigation is separation and delineation of geochemical anomalies for the single element Cu in Mesgaran mining area, eastern Iran. Mesgaran mining area is located in south part of Sarbishe county with about 29 Km distance to the county center. This region is part of an Ophiolite sequence and the copper anomalies seem to be related to a volcanic massive sulfide (VMS) deposit whose main part (massive sulfide Lens) has been eroded. In order to delineate Cu anomalies, the boxplot as an Exploratory Data Analysis (EDA) method and concentration-volume (C-V) Fractal modeling are employed. Both of the methods reveal low-deep anomalies which are highly correlated with geological and geophysical studies. As the main result of this study we show that Fractal modeling in spite of the Boxplot, is not recommended for complex geological settings. The proved shallow anomalies recorded by geophysical studies and defined by the used methods are in accordance to the stringer zone of a volcanic massive sulfide (VMS) deposit in Mesgaran mining area which means this region is the bottom of a VMS deposit and geochemical anomalies are related to the remained parts of the deposit.
Influence of Ferric and Ferrous Iron on Chemical and Bacterial Leaching of Copper Flotation Concentrates  [PDF]
Ali Ahmadi
International Journal of Nonferrous Metallurgy (IJNM) , 2012, DOI: 10.4236/ijnm.2012.13006
Abstract: The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.
Inheritance of Important Economic Traits in Chickens under Short Term Selection
Ardeshir Bahmanimehr
International Journal of Animal and Veterinary Advances , 2012,
Abstract: The aim of this study is study the inheritance of economic traits in an Iranian Native chickens population by estimating genetic parameters (heritability, genetic, phenotypic and environment correlations) under short-term selection in breeding programs. Identification of genes determining the expression of economically important traits of plants and animals is a main research focus in agricultural genomics. Most of these traits are characterized by a wide variability of the expression of genes at certain loci called Quantitative Trait Loci (QTL). Characterization of the chromosomal regions carrying QTL can be applied in marker-assisted Selection (MAS) to improve breeding efficiency. Molecular linkage maps in combination with Powerful statistical methods facilitate the genetic dissection of complex traits, and the chicken is ideally suited for this task due to a relatively short life cycle and large number of progeny. Native chickens are important in some rural areas. They usually produce meat and eggs without extra feed, only picking food. Improving their economical traits, such production efficiency would save these genetic resources. The genetic parameters for various traits of economic importance were studied in an Iranian Native chickens population under short term selection for egg production and body weight for over 2 years. The parameters studied were body weight at day old (BW1) , 8 weeks (BW8) and body weight at 12 weeks (BW12), the weight of first egg (EGGW1) and egg weight at 30 weeks of age (EGGW30) also the average number of stock eggs per day (EGG/DAY). They showed mostly moderate to high heritability estimates. All these values were 0.56 to 0.44, 0.51 0.2, 0.56 and 0.15, respectively. Higher heritability estimate were obtained for body weight traits. There were positive genetic correlation between weight traits and egg weight traits. Higher estimate was obtained for BW1 and EGGW30 (0.64). However, negative genetic correlation between body weight traits and number of eggs are estimated. In the result, selection for body weight traits before mature ages will cause gain in egg weight traits and it will be useful in breeding plans.
A Source Analysis to Ambient Air in Isfahan City, Iran
Ardeshir Kalantari
Journal of Research in Health Sciences , 2011,
Abstract: Background: Airborne particulate matter is one of the most important atmospheric pollutants. Tile sources of particulate matter in the atmosphere are divided into two groups; 1) natural sources and 2) anthropogenic sources. The important components of airborne particulate matter and invarying concentrations are the ubiquitous components of the lower atmosphere. Heavy metals are mainly emitted into the atmosphere ham anthropogenic sources. The major anthropogenic sources of heavy metals in the atmosphere included lI1cineratlon of wastes, smelting of ores, fossil fuel combustion, etc. Methods: In this study, airborne particulate matter from the atmosphere of Isfahan city was collected on paper filter (whatman No. 41) by using a high-volume air sampler sampling period was 24 hours and sampling was performed at five stations. The extraction of heavy metals from airborne particulate matter was performed by a wet digestion procedure. For determining the concentration of heavy metals, the technique of flame atomic absorption was used. Then the enrichment factor (EF) was calculated for different elements (Cu, Cr, Zn, Fe, Pb, Ca, Cd and AI) and compared the individual contributions with A] Results: Table I shows the concentration of heavy metals in crustal of earth. Table 2 summarizes the environmental factor (EF) on ambient aerosols obtained at the five sampling sites. The data show EF= 2558.4 for Cd, EF = 582.8 for Pb, EF = 109.8 for Zn and EF = 40.1 for Cu, and all of them, are added to environment via the human activities and energy consumption. Conclusions
Evaluation of the Accuracy and Automation of Travel Time and Delay Data Collection Methods  [PDF]
Robert Suarez, Ardeshir Faghri, Mingxin Li
Journal of Transportation Technologies (JTTs) , 2014, DOI: 10.4236/jtts.2014.41007

Travel time and delay are among the most important measures for gauging a transportation system’s performance. To address the growing problem of congestion in the US, transportation planning legislation mandated the monitoring and analysis of system performance and produced a renewed interest in travel time and delay studies. The use of traditional sensors installed on major roads (e.g. inductive loops) for collecting data is necessary but not sufficient because of their limited coverage and expensive costs for setting up and maintaining the required infrastructure. The GPS-based techniques employed by the University of Delaware have evolved into an automated system, which provides more realistic experience of a traffic flow throughout the road links. However, human error and the weaknesses of using GPS devices in urban settings still have the potential to create inaccuracies. By simultaneously collecting data using three different techniques, the accuracy of the GPS positioning data and the resulting travel time and delay values could be objectively compared for automation and statistically compared for accuracy. It was found that the new technique provided the greatest automation requiring minimal attention of the data collectors and automatically processing the data sets. The data samples were statistically analyzed by using a combination of parametric and nonparametric statistical tests.

An Interactive Expert System Based Decision Making Model for the Management of Transit System Alternate Fuel Vehicle Assets  [PDF]
Michael L. Vaughan, Ardeshir Faghri, Mingxin Li
Intelligent Information Management (IIM) , 2017, DOI: 10.4236/iim.2017.91001
Abstract: Traditionally, the process used by public transportation entities to determine the acquisition strategy for new vehicle asset is based upon a broad range of criteria. Vehicle cost has been cited as one of the more critical factors which decision makers consider. It is currently a common practice to consider other factors (life-cycle cost, fuel efficiency, vehicle reliability, environmental effects, etc.) that contribute to a more comprehensive approach. This study investigates the next generation of advancements in decision making tools in the area of the application of methods to quantify and manage uncertainty. In particular, the uncertainty comes from the public policy arena where future policy and regulations are not always based upon logical and predictable processes. The fleet decision making process in most governmental agencies is a very complex and interdependent activity. There are always competing forces and agendas within the view of the decision maker. Rarely is the decision maker a single person although, within the transit environment, there is often one person charged with the responsibility of fleet management. The focus of this research examines the decision making of the general transit agency community via the development of an expert systems prototype tool. A computer-based prototype system is developed which provide an expert knowledge-based recommendation, based upon variable user inputs. The results shown in this study show that a decision making tool for the management of transit system alternate fuel vehicle assets can be modeled and tested. The direct users of this research are the transit agency administrations. The results can be used by the management teams as a reliable input to inform their urban transit buses expansion decision making process.
Modeling Bicycle Conflict on Non-Motorized Paths on Suburban College Campuses  [PDF]
Zachary Nerwinski, Ardeshir Faghri, Mingxin Li
Journal of Transportation Technologies (JTTs) , 2018, DOI: 10.4236/jtts.2018.84020
Abstract: Bicycling is an important way for college students and employees to get around campuses. With a rise in bicycling on campuses there comes a rise in bicycle collisions with pedestrians walking to and from classes and work. The literature review showed many papers involving bicycle conflict modeling but on roads with motor vehicles. While some aspects of this research can be applied to non-motorized paths, there is a lack of research strictly focusing on only bicycles and pedestrians. This study aims to fill this knowledge gap by developing a model to identify locations on roads and paths (hotspots) on college campuses that are likely to have a bicycle collision and predict the likelihood of a serious bicycle crash on a non-motorized path based on the characteristics of the path. This study identifies those interactions between bicyclists and pedestrians on non-motorized paths on a suburban college campus in Newark, USA. Findings suggest that pedestrian density of a path is a major factor in the maximum speed bicyclists can achieve. The wider the path is, the higher the maximum speed is that a bicyclist can obtain. This is because a wider path width decreases the pedestrian density. The grade of the path has little effect on bicycle speeds. The results of the models were displayed on a GIS map that is visually appealing to a viewer. The paths were color coded based on their level of safety, so it is easy to observe problematic areas of the network. This technique can be applied to the entire campus network of non-motorized paths to study the whole system. This can then be used by planners and designers to identify areas that need upgrading and improve the overall safety of the non-motorized path system.
Page 1 /1205
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.