Search results for: typical SQL query tasks.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1111

Search results for: typical SQL query tasks.

721 Classification Influence Index and its Application for k-Nearest Neighbor Classifier

Authors: Sejong Oh

Abstract:

Classification is an important topic in machine learning and bioinformatics. Many datasets have been introduced for classification tasks. A dataset contains multiple features, and the quality of features influences the classification accuracy of the dataset. The power of classification for each feature differs. In this study, we suggest the Classification Influence Index (CII) as an indicator of classification power for each feature. CII enables evaluation of the features in a dataset and improved classification accuracy by transformation of the dataset. By conducting experiments using CII and the k-nearest neighbor classifier to analyze real datasets, we confirmed that the proposed index provided meaningful improvement of the classification accuracy.

Keywords: accuracy, classification, dataset, data preprocessing

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720 An Engineering Approach to Forecast Volatility of Financial Indices

Authors: Irwin Ma, Tony Wong, Thiagas Sankar

Abstract:

By systematically applying different engineering methods, difficult financial problems become approachable. Using a combination of theory and techniques such as wavelet transform, time series data mining, Markov chain based discrete stochastic optimization, and evolutionary algorithms, this work formulated a strategy to characterize and forecast non-linear time series. It attempted to extract typical features from the volatility data sets of S&P100 and S&P500 indices that include abrupt drops, jumps and other non-linearity. As a result, accuracy of forecasting has reached an average of over 75% surpassing any other publicly available results on the forecast of any financial index.

Keywords: Discrete stochastic optimization, genetic algorithms, genetic programming, volatility forecast

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719 Generalized Mean-field Theory of Phase Unwrapping via Multiple Interferograms

Authors: Yohei Saika

Abstract:

On the basis of Bayesian inference using the maximizer of the posterior marginal estimate, we carry out phase unwrapping using multiple interferograms via generalized mean-field theory. Numerical calculations for a typical wave-front in remote sensing using the synthetic aperture radar interferometry, phase diagram in hyper-parameter space clarifies that the present method succeeds in phase unwrapping perfectly under the constraint of surface- consistency condition, if the interferograms are not corrupted by any noises. Also, we find that prior is useful for extending a phase in which phase unwrapping under the constraint of the surface-consistency condition. These results are quantitatively confirmed by the Monte Carlo simulation.

Keywords: Bayesian inference, generalized mean-field theory, phase unwrapping, statistical mechanics.

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718 MATLAB-Based Graphical User Interface (GUI) for Data Mining as a Tool for Environment Management

Authors: M. Awawdeh, A. Fedi

Abstract:

The application of data mining to environmental monitoring has become crucial for a number of tasks related to emergency management. Over recent years, many tools have been developed for decision support system (DSS) for emergency management. In this article a graphical user interface (GUI) for environmental monitoring system is presented. This interface allows accomplishing (i) data collection and observation and (ii) extraction for data mining. This tool may be the basis for future development along the line of the open source software paradigm.

Keywords: Data Mining, Environmental data, Mathematical Models, Matlab Graphical User Interface.

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717 PIV Investigation into the Evolution of Vortical Structures in the Zero Pressure Gradient Boundary Layer

Authors: Ishtiaq A. Chaudhry, Zia R. Tahir

Abstract:

Experimental investigation has been carried out towards understanding the complex fluid dynamics involved in the interaction of vortical structures with zero pressure gradient boundary layer. A laminar boundary layer is produced on the flat plate placed in the water flume and the synthetic jet actuator is deployed on top of the plate at a definite distance from the leading edge. The synthetic jet actuator has been designed in such a way that the to and fro motion of the diaphragm is maneuvered at will by varying the operating parameters to produce the typical streamwise vortical structures namely hairpin and tilted vortices. PIV measurements are made on the streamwise plane normal to the plate to evaluate their interaction with the near wall fluid.

Keywords: Boundary layer, synthetic jet actuator, flow separation control, vortical structures.

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716 Polymer Aerostatic Thrust Bearing under Circular Support for High Static Stiffness

Authors: S. W. Lo, C.-H. Yu

Abstract:

A new design of aerostatic thrust bearing is proposed for high static stiffness. The bearing body, which is mead of polymer covered with metallic membrane, is held by a circular ring. Such a support helps form a concave air gap to grasp the air pressure. The polymer body, which can be made rapidly by either injection or molding is able to provide extra damping under dynamic loading. The smooth membrane not only serves as the bearing surface but also protects the polymer body. The restrictor is a capillary inside a silicone tube. It can passively compensate the variation of load by expanding the capillary diameter for more air flux. In the present example, the stiffness soars from 15.85 N/μm of typical bearing to 349.85 N/μm at bearing elevation 9.5 μm; meanwhile the load capacity also enhances from 346.86 N to 704.18 N.

Keywords: Aerostatic, bearing, polymer, static stiffness.

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715 Multi-Agent Approach for Monitoring and Control of Biotechnological Processes

Authors: Ivanka Valova

Abstract:

This paper is aimed at using a multi-agent approach to monitor and diagnose a biotechnological system in order to validate certain control actions depending on the process development and the operating conditions. A multi-agent system is defined as a network of interacting software modules that collectively solve complex tasks. Remote monitoring and control of biotechnological processes is a necessity when automated and reliable systems operating with no interruption of certain activities are required. The advantage of our approach is in its flexibility, modularity and the possibility of improving by acquiring functionalities through the integration of artificial intelligence.

Keywords: Multi-agent approach, artificial intelligence, biotechnological processes, anaerobic biodegradation.

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714 Decision Support System Based on Data Warehouse

Authors: Yang Bao, LuJing Zhang

Abstract:

Typical Intelligent Decision Support System is 4-based, its design composes of Data Warehouse, Online Analytical Processing, Data Mining and Decision Supporting based on models, which is called Decision Support System Based on Data Warehouse (DSSBDW). This way takes ETL,OLAP and DM as its implementing means, and integrates traditional model-driving DSS and data-driving DSS into a whole. For this kind of problem, this paper analyzes the DSSBDW architecture and DW model, and discusses the following key issues: ETL designing and Realization; metadata managing technology using XML; SQL implementing, optimizing performance, data mapping in OLAP; lastly, it illustrates the designing principle and method of DW in DSSBDW.

Keywords: Decision Support System, Data Warehouse, Data Mining.

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713 Selecting the Best Sub-Region Indexing the Images in the Case of Weak Segmentation Based On Local Color Histograms

Authors: Mawloud Mosbah, Bachir Boucheham

Abstract:

Color Histogram is considered as the oldest method used by CBIR systems for indexing images. In turn, the global histograms do not include the spatial information; this is why the other techniques coming later have attempted to encounter this limitation by involving the segmentation task as a preprocessing step. The weak segmentation is employed by the local histograms while other methods as CCV (Color Coherent Vector) are based on strong segmentation. The indexation based on local histograms consists of splitting the image into N overlapping blocks or sub-regions, and then the histogram of each block is computed. The dissimilarity between two images is reduced, as consequence, to compute the distance between the N local histograms of the both images resulting then in N*N values; generally, the lowest value is taken into account to rank images, that means that the lowest value is that which helps to designate which sub-region utilized to index images of the collection being asked. In this paper, we make under light the local histogram indexation method in the hope to compare the results obtained against those given by the global histogram. We address also another noteworthy issue when Relying on local histograms namely which value, among N*N values, to trust on when comparing images, in other words, which sub-region among the N*N sub-regions on which we base to index images. Based on the results achieved here, it seems that relying on the local histograms, which needs to pose an extra overhead on the system by involving another preprocessing step naming segmentation, does not necessary mean that it produces better results. In addition to that, we have proposed here some ideas to select the local histogram on which we rely on to encode the image rather than relying on the local histogram having lowest distance with the query histograms.

Keywords: CBIR, Color Global Histogram, Color Local Histogram, Weak Segmentation, Euclidean Distance.

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712 Assessing and Improving Ramp-Up Capability

Authors: Sebastian Tschöpe, Konja Knüppel, Peter Nyhuis

Abstract:

In times when product life cycles are decreasing, while market demands are increasing, manufacturing enterprises are confronted with the challenge of more frequent and more complex ramp-ups. Thus it becomes obvious that ramp-up management is going to be a topic enterprises have to focus on in the future. Since each ramp-up is unique concerning the product, the process, the technology, the circumstances and the coaction of these four factors, the knowledge of the ramp-up situation and the current ramp-up capability of the enterprise are fundamental requirements for the subsequent improvement of the ramp-up capability of the production system.

In this article a methodology is going to be presented which can be used to define typical production ramp-up situations, to identify the current ramp-up capability of a production system and to improve it with respect to a specific situation. Additionally there will be a description of the functionality of a software-tool developed based on this methodology.

Keywords: Assessment methodology, ramp-up, ramp-up capability, software-tool.

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711 An Efficient Algorithm for Reliability Lower Bound of Distributed Systems

Authors: Mohamed H. S. Mohamed, Yang Xiao-zong, Liu Hong-wei, Wu Zhi-bo

Abstract:

The reliability of distributed systems and computer networks have been modeled by a probabilistic network or a graph G. Computing the residual connectedness reliability (RCR), denoted by R(G), under the node fault model is very useful, but is an NP-hard problem. Since it may need exponential time of the network size to compute the exact value of R(G), it is important to calculate its tight approximate value, especially its lower bound, at a moderate calculation time. In this paper, we propose an efficient algorithm for reliability lower bound of distributed systems with unreliable nodes. We also applied our algorithm to several typical classes of networks to evaluate the lower bounds and show the effectiveness of our algorithm.

Keywords: Distributed systems, probabilistic network, residual connectedness reliability, lower bound.

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710 The Influence of Substrate Bias on the Mechanical Properties of a W- and S-containing DLC-based Solid-lubricant Film

Authors: Guojia Ma, Guoqiang Lin, Shuili Gong, Gang Sun, Dawang Wang

Abstract:

A diamond-like carbon (DLC) based solid-lubricant film was designed and DLC films were successfully prepared using a microwave plasma enhanced magnetron sputtering deposition technology. Post-test characterizations including Raman spectrometry, X-ray diffraction, nano-indentation test, adhesion test, friction coefficient test were performed to study the influence of substrate bias voltage on the mechanical properties of the W- and S-doped DLC films. The results indicated that the W- and S-doped DLC films also had the typical structure of DLC films and a better mechanical performance achieved by the application of a substrate bias of -200V.

Keywords: Adhesive Strength, Coefficient of Friction, Substrate Bias, W- and S-doped DLC film

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709 Descriptive Study of Role Played by Exercise and Diet on Brain Plasticity

Authors: Mridul Sharma, Praveen Saroha

Abstract:

In today's world, everyone has become so busy in their to-do tasks and daily routine that they tend to ignore some of the basal components of our life, including exercise and diet. This comparative study analyzes the pathways of the relationship between exercise and brain plasticity and also includes another variable diet to study the effects of diet on learning by answering questions including which diet is known to be the best learning supporter and what are the recommended quantities of the same. Further, this study looks into inter-relation between diet and exercise, and also some other approach of the relation between diet and exercise on learning apart from through Brain Derived Neurotrophic Factor (BDNF).

Keywords: Basolateral amygdala, brain derived neurotrophic factor, brain plasticity, diet, exercise, mediterranean diet.

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708 Energy Efficient Resource Allocation in Distributed Computing Systems

Authors: Samee Ullah Khan, C. Ardil

Abstract:

The problem of mapping tasks onto a computational grid with the aim to minimize the power consumption and the makespan subject to the constraints of deadlines and architectural requirements is considered in this paper. To solve this problem, we propose a solution from cooperative game theory based on the concept of Nash Bargaining Solution. The proposed game theoretical technique is compared against several traditional techniques. The experimental results show that when the deadline constraints are tight, the proposed technique achieves superior performance and reports competitive performance relative to the optimal solution.

Keywords: Energy efficient algorithms, resource allocation, resource management, cooperative game theory.

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707 Unscented Grid Filtering and Smoothing for Nonlinear Time Series Analysis

Authors: Nikolay Nikolaev, Evgueni Smirnov

Abstract:

This paper develops an unscented grid-based filter and a smoother for accurate nonlinear modeling and analysis of time series. The filter uses unscented deterministic sampling during both the time and measurement updating phases, to approximate directly the distributions of the latent state variable. A complementary grid smoother is also made to enable computing of the likelihood. This helps us to formulate an expectation maximisation algorithm for maximum likelihood estimation of the state noise and the observation noise. Empirical investigations show that the proposed unscented grid filter/smoother compares favourably to other similar filters on nonlinear estimation tasks.

Keywords:

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706 Adaptive Extended Kalman Filter for Ballistic Missile Tracking

Authors: Gaurav Kumar, Dharmbir Prasad, Rudra Pratap Singh

Abstract:

In the current work, adaptive extended Kalman filter (AEKF) is presented for solution of ground radar based ballistic missile (BM) tracking problem in re-entry phase with unknown ballistic coefficient. The estimation of trajectory of any BM in re-entry phase is extremely difficult, because of highly non-linear motion of BM. The estimation accuracy of AEKF has been tested for a typical test target tracking problem adopted from literature. Further, the approach of AEKF is compared with extended Kalman filter (EKF). The simulation result indicates the superiority of the AEKF in solving joint parameter and state estimation problems.

Keywords: Adaptive, AEKF, ballistic missile, EKF, re-entry phase, target tracking.

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705 Fine-Grained Sentiment Analysis: Recent Progress

Authors: Jie Liu, Xudong Luo, Pingping Lin, Yifan Fan

Abstract:

Facebook, Twitter, Weibo, and other social media and significant e-commerce sites generate a massive amount of online texts, which can be used to analyse people’s opinions or sentiments for better decision-making. So, sentiment analysis, especially the fine-grained sentiment analysis, is a very active research topic. In this paper, we survey various methods for fine-grained sentiment analysis, including traditional sentiment lexicon-based methods, ma-chine learning-based methods, and deep learning-based methods in aspect/target/attribute-based sentiment analysis tasks. Besides, we discuss their advantages and problems worthy of careful studies in the future.

Keywords: sentiment analysis, fine-grained, machine learning, deep learning

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704 Information Retrieval in Domain Specific Search Engine with Machine Learning Approaches

Authors: Shilpy Sharma

Abstract:

As the web continues to grow exponentially, the idea of crawling the entire web on a regular basis becomes less and less feasible, so the need to include information on specific domain, domain-specific search engines was proposed. As more information becomes available on the World Wide Web, it becomes more difficult to provide effective search tools for information access. Today, people access web information through two main kinds of search interfaces: Browsers (clicking and following hyperlinks) and Query Engines (queries in the form of a set of keywords showing the topic of interest) [2]. Better support is needed for expressing one's information need and returning high quality search results by web search tools. There appears to be a need for systems that do reasoning under uncertainty and are flexible enough to recover from the contradictions, inconsistencies, and irregularities that such reasoning involves. In a multi-view problem, the features of the domain can be partitioned into disjoint subsets (views) that are sufficient to learn the target concept. Semi-supervised, multi-view algorithms, which reduce the amount of labeled data required for learning, rely on the assumptions that the views are compatible and uncorrelated. This paper describes the use of semi-structured machine learning approach with Active learning for the “Domain Specific Search Engines". A domain-specific search engine is “An information access system that allows access to all the information on the web that is relevant to a particular domain. The proposed work shows that with the help of this approach relevant data can be extracted with the minimum queries fired by the user. It requires small number of labeled data and pool of unlabelled data on which the learning algorithm is applied to extract the required data.

Keywords: Search engines; machine learning, Informationretrieval, Active logic.

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703 HTML5 Online Learning Application with Offline Web, Location Based, Animated Web, Multithread, and Real-Time Features

Authors: Sheetal R. Jadhwani, Daisy Sang, Chang-Shyh Peng

Abstract:

Web applications are an integral part of modem life. They are mostly based upon the HyperText Markup Language (HTML). While HTML meets the basic needs, there are some shortcomings. For example, applications can cease to work once user goes offline, real-time updates may be lagging, and user interface can freeze on computationally intensive tasks. The latest language specification HTML5 attempts to rectify the situation with new tools and protocols. This paper studies the new Web Storage, Geolocation, Web Worker, Canvas, and Web Socket APIs, and presents applications to test their features and efficiencies.

Keywords: HTML5, Web Worker, Canvas, Web Socket.

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702 An Investigation on the Variation of Software Development Productivity

Authors: Zhizhong Jiang, Peter Naudé, Craig Comstock

Abstract:

The productivity of software development is one of the major concerns for project managers. Given the increasing complexity of the software being developed and the concomitant rise in the typical project size, the productivity has not consistently improved. By analyzing the latest release of ISBSG data repository with 4106 projects ever developed, we report on the factors found to significantly influence productivity, and present an original model for the estimation of productivity during project design. We further illustrate that software development productivity has experienced irregular variations between the years 1995 and 2005. Considering the factors significant to productivity, we found its variations are primarily caused by the variations of average team size for the development and the unbalanced use of the less productive development language 3GL.

Keywords: Development Platform, Function Point, Language, Productivity, Software Engineering, Team Size.

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701 Design and Implementation of Real-Time Automatic Censoring System on Chip for Radar Detection

Authors: Imron Rosyadi, Ridha A. Djemal, Saleh A. Alshebeili

Abstract:

Design and implementation of a novel B-ACOSD CFAR algorithm is presented in this paper. It is proposed for detecting radar target in log-normal distribution environment. The BACOSD detector is capable to detect automatically the number interference target in the reference cells and detect the real target by an adaptive threshold. The detector is implemented as a System on Chip on FPGA Altera Stratix II using parallelism and pipelining technique. For a reference window of length 16 cells, the experimental results showed that the processor works properly with a processing speed up to 115.13MHz and processing time0.29 ┬Ás, thus meets real-time requirement for a typical radar system.

Keywords: CFAR, FPGA, radar.

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700 Analysis on Urban Form and Evolution Mechanism of High-Density City: Case Study of Hong Kong

Authors: Yuan Zhang

Abstract:

Along with large population and great demands for urban development, Hong Kong serves as a typical high-density city with multiple altitudes, advanced three-dimensional traffic system, rich city open space, etc. This paper contributes to analyzing its complex urban form and evolution mechanism from three aspects of view, separately as time, space and buildings. Taking both horizontal and vertical dimension into consideration, this paper provides a perspective to explore the fascinating process of growing and space folding in the urban form of high-density city, also as a research reference for related high-density urban design.

Keywords: Evolution mechanism, high-density city, Hong Kong, urban form.

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699 Thermo-Mechanical Treatment of Chromium Alloyed Low Carbon Steel

Authors: L. Kučerová, M. Bystrianský, V. Kotěšovec

Abstract:

Thermo-mechanical processing with various processing parameters was applied to 0.2%C-0.6%Mn-2S%i-0.8%Cr low alloyed high strength steel. The aim of the processing was to achieve the microstructures typical for transformation induced plasticity (TRIP) steels. Thermo-mechanical processing used in this work incorporated two or three deformation steps. The deformations were in all the cases carried out during the cooling from soaking temperatures to various bainite hold temperatures. In this way, 4-10% of retained austenite were retained in the final microstructures, consisting further of ferrite, bainite, martensite and pearlite. The complex character of TRIP steel microstructure is responsible for its good strength and ductility. The strengths achieved in this work were in the range of 740 MPa – 836 MPa with ductility A5mm of 31-41%.

Keywords: Pearlite, retained austenite, thermo-mechanical treatment, TRIP steel.

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698 Re-Thinking Knowledge-Based Management

Authors: Harri Laihonen, Antti Lönnqvist

Abstract:

This paper challenges the relevance of knowledgebased management research by arguing that the majority of the literature emphasizes information and knowledge provision instead of their business usage. For this reason the related processes are considered valuable and eligible as such, which has led to overlapping nature of knowledge-based management disciplines. As a solution, this paper turns the focus on the information usage. Value of knowledge and respective management tasks are then defined by the business need and the knowledge-user becomes the main actor. The paper analyses the prevailing literature streams and recognizes the need for a more focused and robust understanding of knowledgebased value creation. The paper contributes by synthetizing the existing literature and pinpointing the essence of knowledge-based management disciplines.

Keywords: Knowledge-based, knowledge management, value creation.

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697 The Building Thermal Performance and Carbon Sequestration Evaluation for Psophocarpus tetrogonobulus on Biofaçade Wall in the Tropical Environment

Authors: Abdul M. A. Rahman , Foong S. Yeok, Atikah F. Amir

Abstract:

Plants are commonly known for its positive correlation in reducing temperature. Since it can benefit buildings by modifying the microclimate, it-s also believed capable of reducing the internal temperature. Various experiments have been done in Universiti Sains Malaysia, Penang to investigate the comparison in thermal benefits between two rooms, one being a typical control room (exposed wall) and the other a biofacade room (plant shaded wall). The investigations were conducted during non-rainy season for approximately a month. Climbing plant Psophocarpus tetrogonobulus from legume species was selected as insulation for the biofacade wall. Conclusions were made on whether the biofacade can be used to tackle the energy efficiency, based on the parameters taken into consideration.

Keywords: biofacade, thermal benefits, carbon sequestration, Psophocarpus tetrogonobulus.

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696 Photonic Crystals for Novel Applications in Integrated-Optic Communication Systems and Devices

Authors: Vijay Janyani, Neetu Joshi, Jigyasa Pagaria, Parul Pathak

Abstract:

Photonic Crystal (PhC) based devices are being increasingly used in multifunctional, compact devices in integrated optical communication systems. They provide excellent controllability of light, yet maintaining the small size required for miniaturization. In this paper, the band gap properties of PhCs and their typical applications in optical waveguiding are considered. Novel PhC based applications such as nonlinear switching and tapers are considered and simulation results are shown using the accurate time-domain numerical method based on Finite Difference Time Domain (FDTD) scheme. The suitability of these devices for novel applications is discussed and evaluated.

Keywords: Band gap engineering, Nonlinear switching, Photonic crystals, PhC tapers, waveguides.

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695 Numerical Simulation of Plasma Actuator Using OpenFOAM

Authors: H. Yazdani, K. Ghorbanian

Abstract:

This paper deals with modeling and simulation of the plasma actuator with OpenFOAM. Plasma actuator is one of the newest devices in flow control techniques which can delay separation by inducing external momentum to the boundary layer of the flow. The effects of the plasma actuators on the external flow are incorporated into Navier-Stokes computations as a body force vector which is obtained as a product of the net charge density and the electric field. In order to compute this body force vector, the model solves two equations: One for the electric field due to the applied AC voltage at the electrodes and the other for the charge density representing the ionized air. The simulation result is compared to the experimental and typical values which confirms the validity of the modeling.

Keywords: Active flow control, flow field, OpenFOAM, plasma actuator.

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694 Comparing the Performance of the Particle Swarm Optimization and the Genetic Algorithm on the Geometry Design of Longitudinal Fin

Authors: Hassan Azarkish, Said Farahat, S.Masoud H. Sarvari

Abstract:

In the present work, the performance of the particle swarm optimization and the genetic algorithm compared as a typical geometry design problem. The design maximizes the heat transfer rate from a given fin volume. The analysis presumes that a linear temperature distribution along the fin. The fin profile generated using the B-spline curves and controlled by the change of control point coordinates. An inverse method applied to find the appropriate fin geometry yield the linear temperature distribution along the fin corresponds to optimum design. The numbers of the populations, the count of iterations and time to convergence measure efficiency. Results show that the particle swarm optimization is most efficient for geometry optimization.

Keywords: Genetic Algorithm, Geometry Optimization, longitudinal Fin, Particle Swarm Optimization

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693 Evaluation of Dynamic Behavior of a Rotor-Bearing System in Operating Conditions

Authors: Mohammad Hadi Jalali, Behrooz Shahriari, Mostafa Ghayour, Saeed Ziaei-Rad, Shahram Yousefi

Abstract:

Most flexible rotors can be considered as beam-like structures. In many cases, rotors are modeled as one-dimensional bodies, made basically of beam-like shafts with rigid bodies attached to them. This approach is typical of rotor dynamics, both analytical and numerical, and several rotor dynamic codes, based on the finite element method, follow this trend. In this paper, a finite element model based on Timoshenko beam elements is utilized to analyze the lateral dynamic behavior of a certain rotor-bearing system in operating conditions.

Keywords: Finite element method, Operational deflection shape, Timoshenko beam elements, Unbalance response.

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692 How to Connect User Research and not so Forthcoming Technology Scenarios – The Extended Home Environment Case Study

Authors: E. Guercio, A. Marcengo, A. Rapp

Abstract:

This paper draws a methodological framework adopted within an internal Telecomitalia project aimed to identify, on a user centred base, the potential interest towards a technological scenario aimed to extend on a personal bubble the typical communication and media fruition home environment. The problem is that involving user in the early stage of the development of such disruptive technology scenario asking users opinions on something that users actually do not manage even in a rough manner could lead to wrong or distorted results. For that reason we chose an approach that indirectly aim to understand users hidden needs in order to obtain a meaningful picture of the possible interest for a technological proposition non yet easily understandable.

Keywords: Personas, focus groups, scenarios, extended home environment, telecommunication, media.

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