Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 298

Search results for: Amir Vahid

298 In-Situ Synthesis of Zinc-Containing MCM-41 and Investigation of Its Capacity for Removal of Hydrogen Sulfide from Crude Oil

Authors: Nastaran Hazrati, Ali Akbar Miran Beigi, Majid Abdouss, Amir Vahid

Abstract:

Hydrogen sulfide is the most toxic gas of crude oil. Adsorption is an energy-efficient process used to remove undesirable compounds such as H2S in gas or liquid streams by passing the stream through a media bed composed of an adsorbent. In this study, H2S of Iran crude oil was separated via cold stripping then zinc incorporated MCM-41 was synthesized via an in-situ method. ZnO functionalized mesoporous silica samples were characterized by XRD, N2 adsorption and TEM. The obtained results of adsorption of H2S showed superior ability of all the materials and with an increase in ZnO amount adsorption was increased.

Keywords: MCM-41, ZnO, H2S removal, adsorption

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297 An Ontology-Based Framework to Support Asset Integrity Modeling: Case Study of Offshore Riser Integrity

Authors: Mohammad Sheikhalishahi, Vahid Ebrahimipour, Amir Hossein Radman-Kian

Abstract:

This paper proposes an Ontology framework for knowledge modeling and representation of the equipment integrity process in a typical oil and gas production plant. Our aim is to construct a knowledge modeling that facilitates translation, interpretation, and conversion of human-readable integrity interpretation into computer-readable representation. The framework provides a function structure related to fault propagation using ISO 14224 and ISO 15926 OWL-Lite/ Resource Description Framework (RDF) to obtain a generic system-level model of asset integrity that can be utilized in the integrity engineering process during the equipment life cycle. It employs standard terminology developed by ISO 15926 and ISO 14224 to map textual descriptions of equipment failure and then convert it to a causality-driven logic by semantic interpretation and computer-based representation using Lite/RDF. The framework applied for an offshore gas riser. The result shows that the approach can cross-link the failure-related integrity words and domain-specific logic to obtain a representation structure of equipment integrity with causality inference based on semantic extraction of inspection report context.

Keywords: asset integrity modeling, interoperability, OWL, RDF/XML

Procedia PDF Downloads 61
296 Analysis of Hydraulic Velocity in Fishway Using CCHE2D Model

Authors: Amir Abbas Kamanbedast, Masood Mohammad Shafipor, Amir Ghotboddin

Abstract:

Fish way is a structure that in generally using to migrate to the place where they are spawned and is made near the spillway. Preventing fish spawning or migrating to their original place by fishway structures can affect their lives in the river or even erase one access to intended environment. The main objective of these structures is establishing a safe path for fish migration. In the present study first the hydraulic specifications of Hamidieh diversion dam were assessed and then it is problems were evaluated. In this study the dimensions of the fish way, including velocity of pools, were evaluated by CCHE2D software. Then by change slope in this structure streamlines like velocity in the pools were measured. For calibration can be use measuring local velocities in some pools. The information can be seen the fishway width of 0.3 m has minimum rate of descent in the total number of structures (pools and overflow).

Keywords: fishway, velocity, Hamidieh-Diversion Dam, CCHE2D model

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295 Comparative Analysis of Traditional and Modern Roundabouts Using Sidra Intersection

Authors: Amir Mohammad Parvini, Amir Masoud Rahimi

Abstract:

Currently, most parts of the world have shifted from traditional roundabouts to modern roundabouts with respect to the role of roundabouts in reducing accidents, increasing safety, lowering the maintenance costs compared to traffic circles with their improper functional and safety experiences. In this study, field data collected from a current traditional roundabout was analyzed by the software AIMSUN and the obtained numbers were recorded. The modern roundabout was designed by changes in the traditional one, considering the geometric standards listed in regulations. Then, the modern roundabout was analyzed by applying a heterogeneous traffic by a micro-simulation software SIDRA (5.1). The function, capacity, and safety of the roundabout were analyzed assuming the superiority of modern roundabouts and acceptable LOS. The obtained results indicate that the function, capacity, and safety of modern roundabouts are better than traditional ones.

Keywords: traditional roundabout, traffic circles, modern roundabout, AIMSUN, SIDRA

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294 Political Cinema: Rewriting The Malaysian Political History Through Documentary Films

Authors: Raja Rodziah Binti Raja Zainal Hassan

Abstract:

The development of Malaysian political cinema is rapidly taking shape in the local film industry. The paper focuses on the production of independent political documentary by two Malaysian filmmakers, Amir Muhammad and Fahmi Reza. Revolutionary cinema can be understood by utilizing the Third Cinema Theory in order to analyse the meaning and its impact on the audience. The issue surrounding the political cinema in Malaysia is the question of national identity. The implementation of racial or ethnic based politics has resulted in hostility within Malaysia’s multiracial society. Amir Muhammad and Fahmi Reza revisit the Malaysian political history through their films in order to understand the reasons behind the hostility and conflict.

Keywords: Political cinema, third cinema theory, revolutionary cinema, national identity, racial or ethnic politics

Procedia PDF Downloads 310
293 Alternator Fault Detection Using Wigner-Ville Distribution

Authors: Amin Ranjbar, Amir Arsalan Jalili Zolfaghari, Amir Abolfazl Suratgar, Mehrdad Khajavi

Abstract:

This paper describes two stages of learning-based fault detection procedure in alternators. The procedure consists of three states of machine condition namely shortened brush, high impedance relay and maintaining a healthy condition in the alternator. The fault detection algorithm uses Wigner-Ville distribution as a feature extractor and also appropriate feature classifier. In this work, ANN (Artificial Neural Network) and also SVM (support vector machine) were compared to determine more suitable performance evaluated by the mean squared of errors criteria. Modules work together to detect possible faulty conditions of machines working. To test the method performance, a signal database is prepared by making different conditions on a laboratory setup. Therefore, it seems by implementing this method, satisfactory results are achieved.

Keywords: alternator, artificial neural network, support vector machine, time-frequency analysis, Wigner-Ville distribution

Procedia PDF Downloads 297
292 Study of Parameters Affecting the Electrostatic Attractions Force

Authors: Vahid Sabermand, Yousef Hojjat, Majid Hasanzadeh

Abstract:

This paper contains two main parts. In the first part of paper we simulated and studied three type of electrode patterns used in various industries for suspension and handling of the semiconductor and glass and we selected the best pattern by evaluating the electrostatic force, which was comb pattern electrode. In the second part, we investigated the parameters affecting the amount of electrostatic force such as the gap between surface and electrode (g), the electrode width (w), the gap between electrodes (t), the surface permittivity and electrode Length and methods of improvement of adhesion force by changing these values.

Keywords: electrostatic force, electrostatic adhesion, electrostatic chuck, electrostatic application in industry, electroadhesive grippers

Procedia PDF Downloads 287
291 Fast Terminal Sliding Mode Controller For Quadrotor UAV

Authors: Vahid Tabrizi, Reza GHasemi, Ahmadreza Vali

Abstract:

This paper presents robust nonlinear control law for a quadrotor UAV using fast terminal sliding mode control. Fast terminal sliding mode idea is used for introducing a nonlinear sliding variable that guarantees the finite time convergence in sliding phase. Then, in reaching phase for removing chattering and producing smooth control signal, continuous approximation idea is used. Simulation results show that the proposed algorithm is robust against parameter uncertainty and has better performance than conventional sliding mode for controlling a quadrotor UAV.

Keywords: quadrotor UAV, fast terminal sliding mode, second order sliding mode t

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290 CT Medical Images Denoising Based on New Wavelet Thresholding Compared with Curvelet and Contourlet

Authors: Amir Moslemi, Amir movafeghi, Shahab Moradi

Abstract:

One of the most important challenging factors in medical images is nominated as noise.Image denoising refers to the improvement of a digital medical image that has been infected by Additive White Gaussian Noise (AWGN). The digital medical image or video can be affected by different types of noises. They are impulse noise, Poisson noise and AWGN. Computed tomography (CT) images are subjected to low quality due to the noise. The quality of CT images is dependent on the absorbed dose to patients directly in such a way that increase in absorbed radiation, consequently absorbed dose to patients (ADP), enhances the CT images quality. In this manner, noise reduction techniques on the purpose of images quality enhancement exposing no excess radiation to patients is one the challenging problems for CT images processing. In this work, noise reduction in CT images was performed using two different directional 2 dimensional (2D) transformations; i.e., Curvelet and Contourlet and Discrete wavelet transform(DWT) thresholding methods of BayesShrink and AdaptShrink, compared to each other and we proposed a new threshold in wavelet domain for not only noise reduction but also edge retaining, consequently the proposed method retains the modified coefficients significantly that result in good visual quality. Data evaluations were accomplished by using two criterions; namely, peak signal to noise ratio (PSNR) and Structure similarity (Ssim).

Keywords: computed tomography (CT), noise reduction, curve-let, contour-let, signal to noise peak-peak ratio (PSNR), structure similarity (Ssim), absorbed dose to patient (ADP)

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289 Investigating Salafism and Its Founder

Authors: Vahid Hosseinzadeh

Abstract:

Salafism is a movement of thought-religion that was born into Sunni Islam and Hanbali sect. However, many groups and different attitudes call themselves Salafis, but they all have common characteristics, the main of which is radical and retrograde interpretation of Islamic sources. Taqi Ad-Din Ahmad ibn Taymiyyah in the Muslim world was the first thinker who established these thoughts. The authors of this article initially tried to express the meaning of Salafism and its appellation in order to focus on the beliefs and thoughts of Ibn Taymiyyah. In this way, it was tried to extract the intellectual foundations of Ibn Taymiyya from the literature and scientific works of his own using a descriptive-analytical method. Extreme focus on the appearance of Quranic phrases and opposition to any new thing that did not exist in Qur'an, Sunnah and the first 3 centuries of Islam, are among the central feature of his thoughts.

Keywords: Salafism, Ibn Taymiyyah, radical literalism, monotheism, polytheism, takfir

Procedia PDF Downloads 551
288 Evaluation of Mixtures of Recycled Concrete Aggregate and Reclaimed Asphalt Pavement Aggregate in Road Subbases

Authors: Vahid Ayan, Joshua R Omer, Alireza Khavandi, Mukesh C Limbachiya

Abstract:

In Iran, utilization of reclaimed asphalt pavement (RAP) aggregate has become a common practice in pavement rehabilitation during the last ten years. Such developments in highway engineering have necessitated several studies to clarify the technical and environmental feasibility of other alternative materials in road rehabilitation and maintenance. The use of recycled concrete aggregates (RCA) in asphalt pavements is one of the major goals of municipality of Tehran. Nevertheless little research has been done to examine the potential benefits of local RCA. The objective of this study is laboratory investigation of incorporating RCA into RAP for use in unbound subbase application. Laboratory investigation showed that 50%RCA+50%RAP is both technically and economically appropriate for subbase use.

Keywords: Roads & highways, Sustainability, Recycling & reuse of materials

Procedia PDF Downloads 331
287 Application of Imperialist Competitive Algorithm for Optimal Location and Sizing of Static Compensator Considering Voltage Profile

Authors: Vahid Rashtchi, Ashkan Pirooz

Abstract:

This paper applies the Imperialist Competitive Algorithm (ICA) to find the optimal place and size of Static Compensator (STATCOM) in power systems. The output of the algorithm is a two dimensional array which indicates the best bus number and STATCOM's optimal size that minimizes all bus voltage deviations from their nominal value. Simulations are performed on IEEE 5, 14, and 30 bus test systems. Also some comparisons have been done between ICA and the famous Particle Swarm Optimization (PSO) algorithm. Results show that how this method can be considered as one of the most precise evolutionary methods for the use of optimum compensator placement in electrical grids.

Keywords: evolutionary computation, imperialist competitive algorithm, power systems compensation, static compensators, voltage profile

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286 Study on the Stages of Knowledge Flow in Central Libraries of Tehran Universities by the Pattern of American Productivity & Quality Center

Authors: Amir Reza Asnafi, Ehsan Tajabadi, Mohsen Hajizeinolabedini

Abstract:

The purpose of this study is to identify the concept of knowledge flow in central libraries of Tehran universities in by the pattern of American Productivity & Quality Center (APQC). The present study is an applied and descriptive survey in terms of its purpose and the methodology used. In this study, APQC framework was used for data collection. The study population is managers and supervisors of central libraries’ departments of public universities of Tehran belonging to the Ministry of Science, Research and Technology. These libraries include: Central Libraries of Al-Zahra University, Amir Kabir, Tarbiat Modarres, Tehran, Khajeh Nasir Toosi University of Technology, Shahed, Sharif, Shahid Beheshti, Allameh Tabataba'i University, Iran University of Science and Technology. Due to the limited number of members of the community, sampling was not performed and the census was conducted instead. The study of knowledge flow in central libraries of public universities in Tehran showed that in seven dimensions of knowledge flow of APQC, these libraries are far from desirable level and to achieve the ideal point, many activities in the field of knowledge flow need to be made, therefore suggestions were made in this study to reach the desired level. One Sample t Test in this research showed that these libraries are at a poor level in terms of these factors: in the dimensions of creation, identification and use of knowledge at a medium level and in the aspects of knowledge acquisition, review, sharing and access and also Manova test or Multivariable Analyze of Variance proved that there was no significant difference between the dimensions of knowledge flow between these libraries and the status of the knowledge flow in these libraries is at the same level as well. Except for the knowledge creation aspect that is slightly different in this regard that was mentioned before.

Keywords: knowledge flow, knowledge management, APQC, Tehran’s academic university libraries

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285 A Forearm-Wrist Rehabilitation Module for Stroke and Spinal Cord Injuries

Authors: Vahid Mehrabi, Iman Sharifi, H. A. Talebi

Abstract:

The automation of rehabilitation procedure by the implementation of robotic devices can overcome the limitation in conventional physiotherapy methods by increasing training sessions and duration of process. In this paper, the design of a simple rehabilitation robot for forearm-wrist therapy in stroke and spinal cord injuries is presented. Wrist’s biological joint motion is modeled by a gimbal-like mechanism which resembles the human arm anatomy. Presented device is an exoskeleton robot with rotation axes corresponding to human skeleton anatomy. The mechanical structure, actuator and sensor selection, system kinematics and comparison between our device range of motion and required active daily life values is illustrated.

Keywords: rehabilitation, robotic devices, physiotherapy, forearm-wrist

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284 Blockchain Solutions for IoT Challenges: Overview

Authors: Amir Ali Fatoorchi

Abstract:

Regardless of the advantage of LoT devices, they have limitations like storage, compute, and security problems. In recent years, a lot of Blockchain-based research in IoT published and presented. In this paper, we present the Security issues of LoT. IoT has three levels of security issues: Low-level, Intermediate-level, and High-level. We survey and compare blockchain-based solutions for high-level security issues and show how the underlying technology of bitcoin and Ethereum could solve IoT problems.

Keywords: Blockchain, security, data security, IoT

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283 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

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282 Justyna Skrzyńska, Zdzisław Kobos, Zbigniew Wochyński

Authors: Vahid Bairami Rad

Abstract:

Due to the tremendous progress in computer technology in the last decades, the capabilities of computers increased enormously and working with a computer became a normal activity for nearly everybody. With all the possibilities a computer can offer, humans and their interaction with computers are now a limiting factor. This gave rise to a lot of research in the field of HCI (human computer interaction) aiming to make interaction easier, more intuitive, and more efficient. To research eye gaze based interfaces it is necessary to understand both sides of the interaction–the human eye and the eye tracker. The first section gives an overview on the anatomy of the eye. The second section accuracy and calibration issue. The subsequent section presents data from a user study where eye movements have been recorded while watching a video and while surfing the Internet. Statistics on the eye movement during these tasks for several individuals provide typical values and ranges for fixation times and saccade lengths and are the foundation for discussions in later chapters. The data also reveal typical limitations of eye trackers.

Keywords: human computer interaction, gaze tracking, calibration, eye movement

Procedia PDF Downloads 444
281 Economics of Oil and Its Stability in the Gulf Region

Authors: Al Mutawa A. Amir, Liaqat Ali, Faisal Ali

Abstract:

After the World War II, the world economy was disrupted and changed due to oil and its prices. The research in this paper presents the basic statistical features and economic characteristics of the Gulf economy. The main features of the Gulf economies and its heavy dependence on oil exports, its dualism between modern and traditional sectors and its rapidly increasing affluences are particularly emphasized.  In this context, the research in this paper discussed the problems of growth versus development and has attempted to draw the implications for the future economic development of this area.

Keywords: oil prices, GCC, economic growth, gulf oil

Procedia PDF Downloads 259
280 Investigating the Energy Gap and Wavelength of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ Superlattices in Terms of Material Thickness and Al Mole Fraction Using Empirical Tight-Binding Method

Authors: Matineh Sadat Hosseini Gheidari, Vahid Reza Yazdanpanah

Abstract:

In this paper, we used the empirical tight-binding method (ETBM) with sp3s* approximation and considering the first nearest neighbor with spin-orbit interactions in order to model superlattice structure (SLS) of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ grown on GaAs (100) substrate at 300K. In the next step, we investigated the behavior of the energy gap and wavelength of this superlattice in terms of different thicknesses of core materials and Al mole fractions. As a result of this survey, we found out that as the Al composition increases, the energy gap of this superlattice has an upward trend and ranges from 1.42-1.63 eV. Also, according to the wavelength range that we gained from this superlattice in different Al mole fractions and various thicknesses, we can find a suitable semiconductor for a special light-emitting diode (LED) application.

Keywords: energy gap, empirical tight-binding method, light-emitting diode, superlattice, wavelength

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279 Evaluating Electronic Service Quality in Banking Iran

Authors: Vahid Bairami Rad

Abstract:

With the rapid growth of the Internet and the globalization of the market, most enterprises are trying to attract and win customers in the highly competitive electronic market. Better e-service quality will enhance the relationship with customers and their satisfaction. So the measurement of eservice quality is very important but it is a complex process due to the complex nature of services. Literature predicts that there is a lack of universal definition of e-service quality. The e-service quality measures in banking have great importance in achieving high customer base. This paper proposes a conceptual model for measuring e-service quality in Iranian Banking Iran. Nine dimensions reliability, ease of use, personalization, security and trust, website aesthetic, responsiveness, contact and speed of delivery had been identified. The results of this paper may help to develop a proper scale to measure the e-service quality in Iranian Banking Industry, which may assist to maintain and improve the performance and effectiveness of e-service quality to retain customers.

Keywords: electronic banking, Dimensions, customer service quality, electronic, communication

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278 Management Trainee Program

Authors: Ambreen Amir Ali

Abstract:

In todays’ dynamic environment, it has become very crucial to have comprehensive management trainee program to hire future leaders of organization. It is being proved that fresh graduates mostly join organizations because of its institution but later on they leave organization because of their immediate manager or supervisor. The concept of coaching and mentoring in talent management systems are very important, because mentors are those who can advise, facilitate, help and support new entrants to advance in their career. When it comes to going for talent hunt, one point needs to be highlighted that MTs are the raw talent for your organization, now it’s the responsibility of employers to nourish them, polish and developed them so that they can enthusiastically take care of senior leadership roles.

Keywords: management trainee, retention, leadership roles, coaching

Procedia PDF Downloads 551
277 Algorithms used in Spatial Data Mining GIS

Authors: Vahid Bairami Rad

Abstract:

Extracting knowledge from spatial data like GIS data is important to reduce the data and extract information. Therefore, the development of new techniques and tools that support the human in transforming data into useful knowledge has been the focus of the relatively new and interdisciplinary research area ‘knowledge discovery in databases’. Thus, we introduce a set of database primitives or basic operations for spatial data mining which are sufficient to express most of the spatial data mining algorithms from the literature. This approach has several advantages. Similar to the relational standard language SQL, the use of standard primitives will speed-up the development of new data mining algorithms and will also make them more portable. We introduced a database-oriented framework for spatial data mining which is based on the concepts of neighborhood graphs and paths. A small set of basic operations on these graphs and paths were defined as database primitives for spatial data mining. Furthermore, techniques to efficiently support the database primitives by a commercial DBMS were presented.

Keywords: spatial data base, knowledge discovery database, data mining, spatial relationship, predictive data mining

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276 Effect of Riprap Stability on Roughness Bridge Pier in River Bend

Authors: Alireza Masjedi, Amir Taeedi

Abstract:

In this research, by placing the two cylindrical piers without roughness and with roughness with riprap around its, they proceeded to a series of tests. Experiments were done by three relative diameters of riprap with density 2.1 and one rate of discharge 27 lit/s under pure water condition. In each experiment, flow depth measured in terms of failure threshold then stability number calculated by using data obtained. The results of the research showed that the riprap stability in pier with roughness is more pier without roughness because of the pier with roughness is sharp-pointed and reduced horseshoe vortex.

Keywords: riprap stability, roughness, river bend, froude number

Procedia PDF Downloads 247
275 Investigation of Riprap Stability on Roughness Bridge Pier in River Bend

Authors: A. Alireza Masjedi, B. Amir Taeedi

Abstract:

In this research, by placing the two cylindrical piers without roughness and with roughness with riprap around its, they proceeded to a series of tests. Experiments were done by three relative diameters of riprap with density 2.1 and one rate of discharge 27 lit/s under pure water condition. In each experiment, flow depth measured in terms of failure threshold then stability number calculated by using data obtained. The results of the research showed that the riprap stability in pier with roughness is more pier without roughness because of the pier with roughness is sharp-pointed and reduced horseshoe vortex.

Keywords: riprap stability, roughness, river bend, froude number

Procedia PDF Downloads 238
274 Internet Addiction among Students: An Empirical Study in Pondicherry University

Authors: Mashood C., Abdul Vahid K., Ashique C. K.

Abstract:

The technology is growing beyond human expectation. Internet is one of very sophisticated product of the information technology. It has various advantages like connecting the world, simplifying the difficult tasks done in past etc. Simultaneously it has demerits also; that is lack of authenticity and internet addiction. To find out the problems of internet addiction, a study conducted among the Postgraduate students of Pondicherry University and collected 454 samples. The study strictly focused to identify the internet addiction among students, influence and interdependence of personality on internet addiction among first years and second years. To evaluate this, we used two major analysis, these are Confirmatory Factor Analysis (CFA) to predict the internet addiction with the observed data and Logistic Regression to identify the difference between first years and second years in the case of internet addiction. Before applying to the core analysis, the data applied to some preliminary tests to check the model fit. The empirical findings shows that , the students of Pondicherry University are very much addicted to the internet, But there is no such huge difference between first years and second years in case of internet addiction.

Keywords: internet addiction, students, Pondicherry University, empirical study

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273 Differential Transform Method: Some Important Examples

Authors: M. Jamil Amir, Rabia Iqbal, M. Yaseen

Abstract:

In this paper, we solve some differential equations analytically by using differential transform method. For this purpose, we consider four models of Laplace equation with two Dirichlet and two Neumann boundary conditions and K(2,2) equation and obtain the corresponding exact solutions. The obtained results show the simplicity of the method and massive reduction in calculations when one compares it with other iterative methods, available in literature. It is worth mentioning that here only a few number of iterations are required to reach the closed form solutions as series expansions of some known functions.

Keywords: differential transform method, laplace equation, Dirichlet boundary conditions, Neumann boundary conditions

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272 A Word-to-Vector Formulation for Word Representation

Authors: Sandra Rizkallah, Amir F. Atiya

Abstract:

This work presents a novel word to vector representation that is based on embedding the words into a sphere, whereby the dot product of the corresponding vectors represents the similarity between any two words. Embedding the vectors into a sphere enabled us to take into consideration the antonymity between words, not only the synonymity, because of the suitability to handle the polarity nature of words. For example, a word and its antonym can be represented as a vector and its negative. Moreover, we have managed to extract an adequate vocabulary. The obtained results show that the proposed approach can capture the essence of the language, and can be generalized to estimate a correct similarity of any new pair of words.

Keywords: natural language processing, word to vector, text similarity, text mining

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271 Specialized Phytochemical Properties of Stachys inflata Eco-Types in Different Ecological Circumstances of Southern Iran

Authors: Ghasem Khodahami, Vahid Rowshan, Mojtaba Pakparvar

Abstract:

Stachys forms one of the largest genera in the flowering plant family Lamiaceae. The number of species in the genus is estimated from about 300 to about 450 and comprises some 34 species in Iran. This genus is one of the richest sources of diterpenes which are particularly interesting because of their ecological role as antifeedants against different species of insects and for their role as the medicinal properties of the plants. The ecological distribution of Stachys inflata was studied and the resulted eco-types were sampled from four regions ranging 230-340 mm of rainfall and 1690-2125 m a.s.l of height In Fars Province Southern Iran. The essential oils of air-dried samples were obtained by hydrodistillation and analyzed by gas chromatography and gas chromatography/mass spectrometry. The number of secondary metabolites varied from 25 to 50 depending to ecological conditions. The main compounds in these areas were: Germacrene D, Bicyclogermacrene, spathulenol, δ-cadinene. Statistical analysis of photochemical resulted in recognizing 3 distinct groups that show internal variety in these herbs.

Keywords: eco-type, phytochemistry, secondary metabolites, Stachys inflata

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270 Intrusion Detection System Based on Peer to Peer

Authors: Alireza Pour Ebrahimi, Vahid Abasi

Abstract:

Recently by the extension of internet usage, Research on the intrusion detection system takes a significant importance. Many of improvement systems prevent internal and external network attacks by providing security through firewalls and antivirus. In recently years, intrusion detection systems gradually turn from host-based systems and depend on O.S to the distributed systems which are running on multiple O.S. In this work, by considering the diversity of computer networks whit respect to structure, architecture, resource, services, users and also security goals requirement a fully distributed collaborative intrusion detection system based on peer to peer architecture is suggested. in this platform each partner device (matched device) considered as a peer-to-peer network. All transmitted information to network are visible only for device that use security scanning of a source. Experimental results show that the distributed architecture is significantly upgradeable in respect to centralized approach.

Keywords: network, intrusion detection system, peer to peer, internal and external network

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269 Synthesis and Characterisation of Bi-Substituted Magnetite Nanoparticles by Mechanochemical Processing (MCP)

Authors: Morteza Mohri Esfahani, Amir S. H. Rozatian, Morteza Mozaffari

Abstract:

Single phase magnetite nanoparticles and Bi-substituted ones were prepared by mechanochemical processing (MCP). The effects of Bi-substitution on the structural and magnetic properties of the nanoparticles were studied by X-ray Diffraction (XRD) and magnetometry techniques, respectively. The XRD results showed that all samples have spinel phase and by increasing Bi content, the main diffraction peaks were shifted to higher angles, which means the lattice parameter decreases from 0.843 to 0.838 nm and then increases to 0.841 nm. Also, the results revealed that increasing Bi content lead to a decrease in saturation magnetization (Ms) from 74.9 to 48.8 emu/g and an increase in coercivity (Hc) from 96.8 to 137.1 Oe.

Keywords: bi-substituted magnetite nanoparticles, mechanochemical processing, X-ray diffraction, magnetism

Procedia PDF Downloads 457