Search results for: Mohsen Fallah Tafti
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 235

Search results for: Mohsen Fallah Tafti

205 Arabic Text Representation and Classification Methods: Current State of the Art

Authors: Rami Ayadi, Mohsen Maraoui, Mounir Zrigui

Abstract:

In this paper, we have presented a brief current state of the art for Arabic text representation and classification methods. We decomposed Arabic Task Classification into four categories. First we describe some algorithms applied to classification on Arabic text. Secondly, we cite all major works when comparing classification algorithms applied on Arabic text, after this, we mention some authors who proposing new classification methods and finally we investigate the impact of preprocessing on Arabic TC.

Keywords: text classification, Arabic, impact of preprocessing, classification algorithms

Procedia PDF Downloads 469
204 FPGA Implementation of the BB84 Protocol

Authors: Jaouadi Ikram, Machhout Mohsen

Abstract:

The development of a quantum key distribution (QKD) system on a field-programmable gate array (FPGA) platform is the subject of this paper. A quantum cryptographic protocol is designed based on the properties of quantum information and the characteristics of FPGAs. The proposed protocol performs key extraction, reconciliation, error correction, and privacy amplification tasks to generate a perfectly secret final key. We modeled the presence of the spy in our system with a strategy to reveal some of the exchanged information without being noticed. Using an FPGA card with a 100 MHz clock frequency, we have demonstrated the evolution of the error rate as well as the amounts of mutual information (between the two interlocutors and that of the spy) passing from one step to another in the key generation process.

Keywords: QKD, BB84, protocol, cryptography, FPGA, key, security, communication

Procedia PDF Downloads 183
203 Facile Fabrication of Nickel/Zinc Oxide Hollow Spheres Nanostructure and Photodegradation of Congo Red

Authors: Seyed Mohsen Mousavi, Ali Reza Mahjoub, Behjat Afshari

Abstract:

In this work, Nickel/Zinc Oxide hollow spherical structures with high surface area using the template Fructose was prepared by the hydrothermal method using a ultrasonic bath at room temperature was produced and were identified by FTIR, XRD, FE-SEM. The photocatalytic activity of synthesized hollow spherical Nickel/Zinc Oxide was studied in the destruction of Congo red as Azo dye. The results showed that the photocatalytic activity of Nickel/ Zinc Oxide hollow spherical nanostructures is improved compared with zinc oxide hollow sphere and other morphologies.

Keywords: azo dye, hollow spheres, photocatalyst, nickel/zinc oxide

Procedia PDF Downloads 637
202 A Survey on Concurrency Control Methods in Distributed Database

Authors: Seyed Mohsen Jameii

Abstract:

In the last years, remarkable improvements have been made in the ability of distributed database systems performance. A distributed database is composed of some sites which are connected to each other through network connections. In this system, if good harmonization is not made between different transactions, it may result in database incoherence. Nowadays, because of the complexity of many sites and their connection methods, it is difficult to extend different models in distributed database serially. The principle goal of concurrency control in distributed database is to ensure not interfering in accessibility of common database by different sites. Different concurrency control algorithms have been suggested to use in distributed database systems. In this paper, some available methods have been introduced and compared for concurrency control in distributed database.

Keywords: distributed database, two phase locking protocol, transaction, concurrency

Procedia PDF Downloads 352
201 Industrial Investment and Contract Models in Subway Projects: Case Study

Authors: Seyed Habib A. Rahmati, Parsa Fallah Sheikhlari, Morteza Musakhani

Abstract:

This paper studies the structure of financial investment and efficiency on the subway would be created between Hashtgerd and Qazvin in Iran. Regarding ascending rate of transportation between Tehran and Qazvin which directly air pollution, it clearly implies to public transportation requirement between these two cities near Tehran. The railway transportation like subway can help each country to terminate traffic jam which has some advantages such as speed, security, non-pollution, low cost of public transport, etc. This type of transportation needs national infrastructures which require enormous investment. It couldn’t implement without leading and managing funds and investments properly. In order to response 'needs', clear norms or normative targets have to be agreed and obviously it is important to distinguish costs from investment requirements critically. Implementation phase affects investment requirements and financing needs. So recognizing barrier related to investment and the quality of investment (what technologies and services are invested in) is as important as the amounts of investment. Different investment methods have mentioned as follows loan, leasing, equity participation, Line of financing, finance, usance, bay back. Alternatives survey before initiation and analyzing of risk management is one of the most important parts in this project. Observation of similar project cities each country has the own specification to choose investment method.

Keywords: subway project, project investment, project contract, project management

Procedia PDF Downloads 480
200 Protective Effect of Malva sylvestris L. against Sodium Fluoride-Induced Nephrotoxicity in Rat

Authors: Ali Babaei Zarch, S. Kianbakht, H. Fallah Huseini, P. Changaei, A. Mirjalili, J. Salehi

Abstract:

Background: Malva sylvestris L. is widely used in the traditional medicine of Iran and other countries to treat gastrointestinal, respiratory, skin and urological Disorders. Moreover, it has antioxidant property. Objective: In this study the protective effect of Malva sylvestris against sodium fluoride-induced nephrotoxicity in rats were evaluated. Methods: The Malva sylvestris flower extract was injected intraperitoneally at the doses of 100, 200, 400 mg/kg/day to groups of rats ( 10 in each group) for 1 week and subsequently 600 ppm sodium fluoride was added daily to the rats drinking water for 1 additional week. After these steps, the rats’ serum levels of urea, creatinine, reduced glutathione, catalase and malondialdehyde were determined. The histopathology of the rats’ kidney was also studied. Results: Malva sylvesteries extract with doses of 400 mg/kg/day significantly decreased the urea and creatinine levels (P<0.05). Moreover, the levels of catalase and glutathione were increased by this dose, but only the catalase increase was statistically significant (P<0.05). All three extract doses of Malva decreased the malondialdehyde level, but it was significant only for the dose 400 mg/kg/day (P<0.05). Histopathological findings also showed a protective effect of Malva against renal damage induced by sodium fluoride. Conclusion: The results suggest that Malva sylvestris has a protective effect against sodium fluoride-induced nephrotoxicity through its antioxidant property.

Keywords: Malva sylvestris, mephrotoxicity, sodium fluoride, rat  

Procedia PDF Downloads 337
199 Legacy of Islamic Hadith and Biodiversity

Authors: Mohsen Nouraei, M. Amouei

Abstract:

Islamic studies are considered in both the Quran and Hadith. Hadith is defined as a set of reports that narrated the words, and behaviors, of infallible persons such as the holy Prophet (pbuh) or the Infallible Imams (as). The issue of biodiversity which is the one of the most important environmental aspects is considered in the field of Hadith. The present paper has investigated biodiversity on the basis of descriptive-analytical methods and with the approach of library-documentary. The household of the Prophet (as) have referred biodiversity that were included diversity of animals, plants, climate etc. In addition to, they also have emphasized on the human need to keep diversity and no damage. It should be noted that they have expressed the rights of the animals and plants for correct using of human, so that human can use these rights in conservation of diversity and their generation.

Keywords: biodiversity, conservation of biodiversity, degradation of biodiversity, extinction of biodiversity

Procedia PDF Downloads 463
198 Analysis of Creative City Indicators in Isfahan City, Iran

Authors: Reza Mokhtari Malek Abadi, Mohsen Saghaei, Fatemeh Iman

Abstract:

This paper investigates the indices of a creative city in Isfahan. Its main aim is to evaluate quantitative status of the creative city indices in Isfahan city, analyze the dispersion and distribution of these indices in Isfahan city. Concerning these, this study tries to analyze the creative city indices in fifteen area of Isfahan through secondary data, questionnaire, TOPSIS model, Shannon entropy and SPSS. Based on this, the fifteen areas of Isfahan city have been ranked with 12 factors of creative city indices. The results of studies show that fifteen areas of Isfahan city are not equally benefiting from creative indices and there is much difference between the areas of Isfahan city.

Keywords: grading, creative city, creative city evaluation indicators, regional planning model

Procedia PDF Downloads 470
197 Development of Femoral Head Osteonecrosis Due to Corticosteroids Consumption; Probable Role of OCP: A Case Report

Authors: S. Alireza Mirghasemi, Shervin Rashidinia, Mohammad Saleh Sadeghi, Mohsen Talebizadeh, Narges Rahimi Gabaran, Seyed Shahin Eftekhari, Sara Shahmoradi

Abstract:

Avascular necrosis of femoral head is a pathologic condition that the main cause is decreased blood supply of femoral head. Among predisposing risk factors, chronic use of corticosteroids, alcoholism, smocking and hip traumas have more important role. Also we can mention OCP consumption as a risk factor among less common predisposing factors that lead to AVNF, in this study we introduce another cause of AVNF with a period of treatment with moderate dose of corticosteroids accompanied by OCP as a probable facilitating factor that leads to AVNF.

Keywords: AVN, corticosteroids consumption, femoral head osteonecrosis, OCP

Procedia PDF Downloads 465
196 Relationship between Legacy of Islamic Hadith and Biodiversity

Authors: Mohsen Nouraei, Maryam Amouei

Abstract:

Islamic studies are considered in both the Quran and Hadith. Hadith is defined as a set of reports that narrated the words and behaviors of infallible persons such as the holy Prophet (pbuh) or the Infallible Imams (as). The issue of biodiversity which is the one of the most important environmental aspects is considered in the field of Hadith. The present paper has investigated biodiversity on the basis of descriptive-analytical methods and with the approach of library-documentary. The household of the Prophet (as) have referred biodiversity that were included diversity of animals, plants, climate etc. In addition, they also have emphasized on the human need to keep diversity and no damage. It should be noted that they have expressed the rights of the animals and plants for correct using of human, so that human can use these rights in conservation of diversity and their generation.

Keywords: biodiversity, conservation of biodiversity, degradation of biodiversity, extinction of biodiversity

Procedia PDF Downloads 450
195 Development of an Elastic Functionally Graded Interphase Model for the Micromechanics Response of Composites

Authors: Trevor Sabiston, Mohsen Mohammadi, Mohammed Cherkaoui, Kaan Inal

Abstract:

A new micromechanics framework is developed for long fibre reinforced composites using a single fibre surrounded by a functionally graded interphase and matrix as a representative unit cell. The unit cell is formulated to represent any number of aligned fibres by a single fibre. Using this model the elastic response of long fibre composites is predicted in all directions. The model is calibrated to experimental results and shows very good agreement in the elastic regime. The differences between the proposed model and existing models are discussed.

Keywords: computational mechanics, functionally graded interphase, long fibre composites, micromechanics

Procedia PDF Downloads 319
194 An Investigation into Fraud Detection in Financial Reporting Using Sugeno Fuzzy Classification

Authors: Mohammad Sarchami, Mohsen Zeinalkhani

Abstract:

Always, financial reporting system faces some problems to win public ear. The increase in the number of fraud and representation, often combined with the bankruptcy of large companies, has raised concerns about the quality of financial statements. So, investors, legislators, managers, and auditors have focused on significant fraud detection or prevention in financial statements. This article aims to investigate the Sugeno fuzzy classification to consider fraud detection in financial reporting of accepted firms by Tehran stock exchange. The hypothesis is: Sugeno fuzzy classification may detect fraud in financial reporting by financial ratio. Hypothesis was tested using Matlab software. Accuracy average was 81/80 in Sugeno fuzzy classification; so the hypothesis was confirmed.

Keywords: fraud, financial reporting, Sugeno fuzzy classification, firm

Procedia PDF Downloads 248
193 The Relationship between Selfesteem, Social Support, and Mental Health among High School Students in Iran

Authors: Mohsen Shahbakhti

Abstract:

The aim of this study was to examine the relationship between self-esteem, social support and mental health in a sample of government high school students in Eshtehard city in Alborz Province in Iran. Three hundred and eleven students (boys) were included in this study. All participants completed the General Health Questionnaire (GHQ 12), Multidimensional Scale of Perceived Social Support (MSPSS -12), and Self-Esteem Scale (SS-10). The results revealed that self-esteem was positively associated with social support. Self-esteem and social support negatively associated with psychological distress. Self-esteem and social support to influence on mental health.

Keywords: self-esteem, social support, mental health, high school students

Procedia PDF Downloads 484
192 Stochastic Energy and Reserve Scheduling with Wind Generation and Generic Energy Storage Systems

Authors: Amirhossein Khazali, Mohsen Kalantar

Abstract:

Energy storage units can play an important role to provide an economic and secure operation of future energy systems. In this paper, a stochastic energy and reserve market clearing scheme is presented considering storage energy units. The approach is proposed to deal with stochastic and non-dispatchable renewable sources with a high level of penetration in the energy system. A two stage stochastic programming scheme is formulated where in the first stage the energy market is cleared according to the forecasted amount of wind generation and demands and in the second stage the real time market is solved according to the assumed scenarios.

Keywords: energy and reserve market, energy storage device, stochastic programming, wind generation

Procedia PDF Downloads 574
191 Peaceful Coexistence with Non-Muslims from the Perspective of Quran

Authors: Mohsen Nouraei

Abstract:

Peaceful coexistence with other religions is one of the most important matters raised the issue of religious diversity. Some people believe that the Quranic policy about the non-Muslims is based on the war and regard the reason of the progress of Islam in the early centuries as based on sword force. This article, which is written in a descriptive and analytical method, investigates this claim and evaluates it with the teachings and instructions of the Quran. The result of this paper shows that not only the teachings of the Quran do not cause the problems, but also The Quranic verses has obligated the Muslims to interact peacefully with their doctrinal opponents and exercise justice in this regard. This paper shows that the principle of interaction with non-Muslims is based on peace and coexistence, and Islam is the inspirer of religious coexistence with the followers of other religions.

Keywords: Quran, peace, religious coexistence, Christians, Jewish

Procedia PDF Downloads 418
190 Evaluation of Malva sylvestris L. Effect on Sodium Fluoride-Induced Nephrotoxicity in Rat

Authors: A. Babaei Zarch, S. Kianbakht, H. Fallah Huseini, P. Changaei, A. Mirjalili, J. Salehi

Abstract:

Background: Malva Sylvestris L. has antioxidant property and is widely used in the traditional medicine to treat gastrointestinal, respiratory, skin and urological disorders. Objective: In this study the protective effect of Malva Sylvestris against sodium fluoride-induced nephrotoxicity in rat were evaluated. Methods: The Malva Sylvestris flower extract was prepared and injected intraperitoneally at the doses of 100, 200, 400 mg/kg/day to group of rats ( 10 in each group) for 1 week and subsequently 600 ppm sodium fluoride was added to the rats drinking water for 1 additional week. After these steps, the rats’ serum levels of urea, creatinine, reduced glutathione, catalase and malondialdehyde were determined. The histopathologies of the rats’ kidneys were also studied. Results: Sodium fluoride administration increased levels of BUN, creatinine glutathione, catalase activity and decreased malondialdehyde indicating induction of nephrotoxicity in rats. Malva Sylvestris extract pretreatment significantly decreased the BUN and creatinine levels (P<0.05). Moreover, the levels of catalase and glutathione were increased by Malva, and this increase were also statistically significant (P<0.05). All three doses of Malva extract decreased the malondialdehyde level, but it was significant only for the doses of 200 and 400 mg/kg/day (P<0.05). Histopathological findings also showed protective effect of Malva against renal damage induced by sodium fluoride. Conclusion: The results suggest that Malva Sylvestris has protective effect against sodium fluoride-induced nephrotoxicity maybe mediated by its antioxidant property.

Keywords: malva sylvestris, nephrotoxicity, sodium fluoride, rat

Procedia PDF Downloads 288
189 Refined Edge Detection Network

Authors: Omar Elharrouss, Youssef Hmamouche, Assia Kamal Idrissi, Btissam El Khamlichi, Amal El Fallah-Seghrouchni

Abstract:

Edge detection is represented as one of the most challenging tasks in computer vision, due to the complexity of detecting the edges or boundaries in real-world images that contains objects of different types and scales like trees, building as well as various backgrounds. Edge detection is represented also as a key task for many computer vision applications. Using a set of backbones as well as attention modules, deep-learning-based methods improved the detection of edges compared with the traditional methods like Sobel and Canny. However, images of complex scenes still represent a challenge for these methods. Also, the detected edges using the existing approaches suffer from non-refined results while the image output contains many erroneous edges. To overcome this, n this paper, by using the mechanism of residual learning, a refined edge detection network is proposed (RED-Net). By maintaining the high resolution of edges during the training process, and conserving the resolution of the edge image during the network stage, we make the pooling outputs at each stage connected with the output of the previous layer. Also, after each layer, we use an affined batch normalization layer as an erosion operation for the homogeneous region in the image. The proposed methods are evaluated using the most challenging datasets including BSDS500, NYUD, and Multicue. The obtained results outperform the designed edge detection networks in terms of performance metrics and quality of output images.

Keywords: edge detection, convolutional neural networks, deep learning, scale-representation, backbone

Procedia PDF Downloads 102
188 Integration of FMEA and Human Factor in the Food Chain Risk Assessment

Authors: Mohsen Shirani, Micaela Demichela

Abstract:

During the last decades, a number of food crises such as Bovine Spongiform Encephalopathy (BSE), Mad-Cow disease, Dioxin in chicken food, Food-and-Mouth Disease (FMD), have certainly inflicted the reliability of the food industry. Consequently, the trend in applying different scientific methods of risk assessment in food safety has obtained more attentions in the academic and practice. However, lack of practical approach considering entire food supply chain is tangible in the academic literature. In this regard, this paper aims to apply risk assessment tool (FMEA) with integration of Human Factor along the entire supply chain of food production and test the method in a case study of Diary production, and analyze its results.

Keywords: FMEA, food supply chain, risk assessment, human factor

Procedia PDF Downloads 447
187 Comparing the Effect of Exercise Time (Morning and Evening) on Troponin T in Males with Cardiovascular Disease

Authors: Amin Mehrabi, Mohsen Salesi, Pourya Pasavand

Abstract:

Context and objective: The purpose of this research is to study the effect of exercise time (morning/evening) on amount of Troponin T in males' plasma suffering from cardiovascular disease. Method: 15 cardiovascular patients selected as the research subjects. At 7 a.m. pretest blood samples taken from the subjects and they did the exercise protocol in presence of a doctor. Immediately after and 3 hours after that blood measurements done. A week later, the subjects did the same steps at 7 p.m. The SPSS v.20 software used to analyze data. Findings: This study proved that circadian rhythm does not have any effect on the response of myocarditis tissue to exercise and cardiovascular patients allowed to exercise in any times of a day.

Keywords: cardiovascular disease, time of exercise, troponin T (cTnT), myocarditis

Procedia PDF Downloads 508
186 DG Power Plants Placement and Evaluation of its Effect on Improving Voltage Security Margin in Radial Distribution Networks

Authors: Atabak Faramarzpour, Mohsen Mohammadian

Abstract:

In this article, we introduce the stability of power system voltage and state DG power plants placement and its effect on improving voltage security margin in radial distribution networks. For this purpose, first, important definitions in voltage stability area such as small and big voltage disturbances, instability, and voltage collapse, and voltage security definitions are stated. Then, according to voltage collapse time, voltage stability is classified and each one's characteristics are stated.

Keywords: DG power plants, evaluation, voltage security, radial distribution networks

Procedia PDF Downloads 670
185 A Proposed Approach for Emotion Lexicon Enrichment

Authors: Amr Mansour Mohsen, Hesham Ahmed Hassan, Amira M. Idrees

Abstract:

Document Analysis is an important research field that aims to gather the information by analyzing the data in documents. As one of the important targets for many fields is to understand what people actually want, sentimental analysis field has been one of the vital fields that are tightly related to the document analysis. This research focuses on analyzing text documents to classify each document according to its opinion. The aim of this research is to detect the emotions from text documents based on enriching the lexicon with adapting their content based on semantic patterns extraction. The proposed approach has been presented, and different experiments are applied by different perspectives to reveal the positive impact of the proposed approach on the classification results.

Keywords: document analysis, sentimental analysis, emotion detection, WEKA tool, NRC lexicon

Procedia PDF Downloads 442
184 Health Risks Evaluation of Heavy Metals in Sea Food from Persian ‎Gulf

Authors: Mohsen Ehsanpour, Maryam Ehsanpour, ‎Majid Afkhami, Fatemeh Afkhami ‎

Abstract:

Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cd, Pb) was investigated in muscle, liver in six different fish species seasonally collected in Persian Gulf (autumn 2009-summer 2010). The concentrations of all metals were lower in flesh than those recorded in liver due to their physiological roles. The THQ index for fish was calculated. Estimation of target hazard quotients calculations for the contaminated fish consumption was calculated to evaluate the effect of pollution on health. Total metal THQs values (Pb and Cd) for adults were 0.05 and 0.04 in Bushehr and Bandar-Genaveh, respectively, and for children they were 0.08 and 0.05 in Bandar-Abbas and Bandar-Lengeh, respectively.

Keywords: Persian Gulf, heavy metals, health risks, THQ index

Procedia PDF Downloads 716
183 Increasing of Resiliency by Using Gas Storage in Iranian Gas Network

Authors: Mohsen Dourandish

Abstract:

Iran has a huge pipeline network in every state of country which is the longest and vastest pipeline network after Russia and USA (360,000 Km high pressure pipelines and 250,000 Km distribution networks). Furthermore in recent years National Iranian Gas Company is planning to develop natural gas network to cover all cities and villages above 20 families, in a way that 97 percent of Iran population will be gas consumer by 2020. In this condition, network resiliency will be the first priority of NIGC and due to that several planning for increasing resiliency of gas network is under construction. The most important strategy of NIGC is converting tree form pattern network to loop gas networks and developing underground gas storage near main gas consuming centers. In this regard NIGC is planning for construction of over 3500 km high-pressure pipeline and also 10 TCM gas storage capacities in UGSs.

Keywords: Iranian gas network, peak shaving, resiliency, underground gas storage

Procedia PDF Downloads 325
182 Emulsified Oil Removal in Produced Water by Graphite-Based Adsorbents Using Adsorption Coupled with Electrochemical Regeneration

Authors: Zohreh Fallah, Edward P. L. Roberts

Abstract:

One of the big challenges for produced water treatment is removing oil from water in the form of emulsified droplets which are not easily separated. An attractive approach is adsorption, as it is a simple and effective process. However, adsorbents must be regenerated in order to make the process cost effective. Several sorbents have been tested for treating oily wastewater. However, some issues such as high energy consumption for activated carbon thermal regeneration have been reported. Due to their significant electrical conductivity, Graphite Intercalation Compounds (GIC) were found to be suitable to be regenerated electrochemically. They are non-porous materials with low surface area and fast adsorptive capacity which are useful for removal of low concentration of organics. An innovative adsorption/regeneration process has been developed at the University of Manchester in which adsorption of organics are done by using a patented GIC adsorbent coupled with subsequent electrochemical regeneration. The oxidation of adsorbed organics enables 100% regeneration so that the adsorbent can be reused over multiple adsorption cycles. GIC adsorbents are capable of removing a wide range of organics and pollutants; however, no comparable report is available for removal of emulsified oil in produced water using abovementioned process. In this study the performance of this technology for the removal of emulsified oil in wastewater was evaluated. Batch experiments were carried out to determine the adsorption kinetics and equilibrium isotherm for both real produced water and model emulsions. The amount of oil in wastewater was measured by using the toluene extraction/fluorescence analysis before and after adsorption and electrochemical regeneration cycles. It was found that oil in water emulsion could be successfully treated by the treatment process and More than 70% of oil was removed.

Keywords: adsorption, electrochemical regeneration, emulsified oil, produced water

Procedia PDF Downloads 582
181 Toward Cloud E-learning System Based on Smart Tools

Authors: Mohsen Maraoui

Abstract:

In the face of the growth in the quantity of data produced, several methods and techniques appear to remedy the problems of processing and analyzing large amounts of information mainly in the field of teaching. In this paper, we propose an intelligent cloud-based teaching system for E-learning content services. This system makes easy the manipulation of various educational content forms, including text, images, videos, 3 dimensions objects and scenes of virtual reality and augmented reality. We discuss the integration of institutional and external services to provide personalized assistance to university members in their daily activities. The proposed system provides an intelligent solution for media services that can be accessed from smart devices cloud-based intelligent service environment with a fully integrated system.

Keywords: cloud computing, e-learning, indexation, IoT, learning in Arabic language, smart tools

Procedia PDF Downloads 135
180 A Novel Model for Saturation Velocity Region of Graphene Nanoribbon Transistor

Authors: Mohsen Khaledian, Razali Ismail, Mehdi Saeidmanesh, Mahdiar Hosseinghadiry

Abstract:

A semi-analytical model for impact ionization coefficient of graphene nanoribbon (GNR) is presented. The model is derived by calculating probability of electrons reaching ionization threshold energy Et and the distance traveled by electron gaining Et. In addition, ionization threshold energy is semi-analytically modeled for GNR. We justify our assumptions using analytic modeling and comparison with simulation results. Gaussian simulator together with analytical modeling is used in order to calculate ionization threshold energy and Kinetic Monte Carlo is employed to calculate ionization coefficient and verify the analytical results. Finally, the profile of ionization is presented using the proposed models and simulation and the results are compared with that of silicon.

Keywords: nanostructures, electronic transport, semiconductor modeling, systems engineering

Procedia PDF Downloads 473
179 The Role of Nano-Science in Construction of Civil Engineering and Environment

Authors: Mehrdad Abkenari, Naghmeh Pournayeb, Mohsen Ramezan Shirazi

Abstract:

Nano-science has been widely used in different engineering sciences. Generally, materials’ application can be determined through their chemical and physical properties. Nano-science has introduced as a new way in production systems that not only turns the materials into very small particles but also, gives them new and considerable properties. Like other fields of study, civil engineering has not been ignorant of benefits and characteristics of new nanotechnology and has used it in the construction industry and environmental engineering. Therefore, considering such chemical properties as elemental analysis and molecular or atomic structure, the present article is aimed at studying the effects of Nano-materials on different branches of civil engineering. Finally, by identifying new Nano-materials, this study attempts to introduce advantages of using these materials for increasing the strength of materials during construction as well as finding new approaches to prevent or reduce the entrance of chemical pollutants during or after construction to the environment.

Keywords: civil, nano-science, construction, environment

Procedia PDF Downloads 412
178 On Direct Matrix Factored Inversion via Broyden's Updates

Authors: Adel Mohsen

Abstract:

A direct method based on the good Broyden's updates for evaluating the inverse of a nonsingular square matrix of full rank and solving related system of linear algebraic equations is studied. For a matrix A of order n whose LU-decomposition is A = LU, the multiplication count is O (n3). This includes the evaluation of the LU-decompositions of the inverse, the lower triangular decomposition of A as well as a “reduced matrix inverse”. If an explicit value of the inverse is not needed the order reduces to O (n3/2) to compute to compute inv(U) and the reduced inverse. For a symmetric matrix only O (n3/3) operations are required to compute inv(L) and the reduced inverse. An example is presented to demonstrate the capability of using the reduced matrix inverse in treating ill-conditioned systems. Besides the simplicity of Broyden's update, the method provides a mean to exploit the possible sparsity in the matrix and to derive a suitable preconditioner.

Keywords: Broyden's updates, matrix inverse, inverse factorization, solution of linear algebraic equations, ill-conditioned matrices, preconditioning

Procedia PDF Downloads 479
177 Using Cooperation Approaches at Different Levels of Artificial Bee Colony Method

Authors: Vahid Zeighami, Mohsen Ghsemi, Reza Akbari

Abstract:

In this work, a Multi-Level Artificial Bee Colony (called MLABC) is presented. In MLABC two species are used. The first species employs n colonies in which each of the them optimizes the complete solution vector. The cooperation between these colonies is carried out by exchanging information through a leader colony, which contains a set of elite bees. The second species uses a cooperative approach in which the complete solution vector is divided to k sub-vectors, and each of these sub-vectors is optimized by a a colony. The cooperation between these colonies is carried out by compiling sub-vectors into the complete solution vector. Finally, the cooperation between two species is obtained by exchanging information between them. The proposed algorithm is tested on a set of well known test functions. The results show that MLABC algorithms provide efficiency and robustness to solve numerical functions.

Keywords: artificial bee colony, cooperative, multilevel cooperation, vector

Procedia PDF Downloads 446
176 Seismic Evaluation of Connected and Disconnected Piled Raft Foundations

Authors: Ali Fallah Yeznabad, Mohammad H. Baziar, Alireza Saedi Azizkandi

Abstract:

Rafts may be used when a low bearing capacity exists underneath the foundation and may be combined by piles in some special circumstances; such as to reduce settlements or high groundwater to control buoyancy. From structural point of view, these piles could be both connected or disconnected from the raft and are to be classified as Piled Rafts (PR) or Disconnected Piled Rafts (DPR). Although the researches about the behavior of piled rafts subjected to vertical loading is really extensive, in the context of dynamic load and earthquake loading, the studies are very limited. In this study, to clarify these foundations’ performance under dynamic loading, series of Shaking Table tests have been performed. The square raft and four piles in connected and disconnected configurations were used in dry silica sand and the model was experimented using a shaking table under 1-g conditions. Moreover, numerical investigation using finite element software have been conducted to better understand the differences and advantages. Our observations demonstrates that in connected Piled Rafts piles have to bear greater amount of moment in their upper parts, however this moments are approximately 40% lower in disconnected piled rafts in the same conditions and loading. Considering the Rafts’ lateral movement which be of crucial importance in foundations performance evaluation, connected piled rafts show much better performance with about 30% less lateral movement. Further, it was observed on confirmed both through laboratory tests and numerical analysis, that adding the superstructure over the piled raft foundation the raft separates from the soil and it significantly increases rocking of the raft which was observed to be the main reason of increase in piles’ moments under superstructure interaction with the foundation.

Keywords: Piled Rafts (PR), Disconnected Piled Rafts (DPR), dynamic loading, shaking table, seismic performance

Procedia PDF Downloads 430