Search results for: complete orthogonal semantic space
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2556

Search results for: complete orthogonal semantic space

2016 Satellite Thermal Control: Cooling by a Diphasic Loop

Authors: L. Boukhris, A. Boudjemai, A. Bellar, R. Roubache, M. Bensaada

Abstract:

In space during functioning, a satellite will be heated up due to the behavior of its components such as power electronics. In order to prevent problems in the satellite, this heat has to be released in space thanks to the cooling system. This system consists of a loop heat pipe (LHP), in which a fluid streams through an evaporator and a condenser. In the evaporator, the fluid captures the heat from the satellite and evaporates. Then it flows to the condenser where it releases the heat and it condenses. In this project, the two mains parts of a cooling system are studied: the evaporator and the condenser. The study of the diphasic loop was done starting from digital simulations carried out under Matlab and Femlab.

Keywords: capillarity, condenser, evaporator, phase change, transfer of heat.

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2015 Spatial Integration at the Room-Level of 'Sequina' Slum Area in Alexandria, Egypt

Authors: Ali Essam El Shazly

Abstract:

The social logic of 'Sequina' slum area in Alexandria details the integral measure of space syntax at the room-level of twenty-building samples. The essence of spatial structure integrates the central 'visitor' domain with the 'living' frontage of the 'children' zone against the segregated privacy of the opposite 'parent' depth. Meanwhile, the multifunctioning of shallow rooms optimizes the integral 'visitor' structure through graph and visibility dimensions in contrast to the 'inhabitant' structure of graph-tails out of sight. Common theme of the layout integrity increases in compensation to the decrease of room visibility. Despite the 'pheno-type' of collective integration, the individual layouts observe 'geno-type' structure of spatial diversity per room adjoins. In this regard, the layout integrity alternates the cross-correlation of the 'kitchen & living' rooms with the 'inhabitant & visitor' domains of 'motherhood' dynamic structure. Moreover, the added 'grandparent' restructures the integral measure to become the deepest space, but opens to the 'living' of 'household' integrity. Some isomorphic layouts change the integral structure just through the 'balcony' extension of access, visual or ignored 'ringiness' of space syntax. However, the most integrated or segregated layouts invert the 'geno-type' into a shallow 'inhabitant' centrality versus the remote 'visitor' structure. Overview of the multivariate social logic of spatial integrity could never clarify without the micro-data analysis.

Keywords: Alexandria, Sequina slum, spatial integration, space syntax.

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2014 Holomorphic Prioritization of Sets within Decagram of Strategic Decision Making of POSM Using Operational Research (OR): Analytic Hierarchy Process (AHP) Analysis

Authors: Elias O. Tembe, Hussain A. Al-Salamin

Abstract:

There is decagram of strategic decisions of operations and production/service management (POSM) within operational research (OR) which must collate, namely: design, inventory, quality, location, process and capacity, layout, scheduling, maintain ace, and supply chain. This paper presents an architectural configuration conceptual framework of a decagram of sets decisions in a form of mathematical complete graph and abelian graph. Mathematically, a complete graph is undirected (UDG), and directed (DG) a relationship where every pair of vertices is connected, collated, confluent, and holomorphic. There has not been any study conducted which, however, prioritizes the holomorphic sets which of POMS within OR field of study. The study utilizes OR structured technique known as The Analytic Hierarchy Process (AHP) analysis for organizing, sorting and prioritizing(ranking) the sets within the decagram of POMS according to their attribution (propensity), and provides an analysis how the prioritization has real-world application within the 21st century.

Keywords: AHP analysis, Decagram, Decagon, Holomorphic.

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2013 A Novel Spectrum Sensing Scheme Based on Periodicity of DVB-T Pilot Signals

Authors: Hyung-Weon Cho, Youngyoon Lee, Seung Goo Kang, Dahae Chong, Myungsoo Lee, Chonghan Song, Seokho Yoon

Abstract:

This paper proposes a novel spectrum sensing technique for the digital video broadcasting-terrestrial (DVB-T) systems, which utilizes the periodicity of pilot signals in the orthogonal frequency division multiplexing (OFDM) symbols. The proposed scheme can overcome the effect of the timing synchronization error by recorrelating the correlation values in the same sample distances. The numerical results demonstrate that the detection probability performance of the proposed scheme outperforms that of the conventional scheme when there exists a timing synchronization error.

Keywords: DVB-T, spectrum sensing, OFDM, timing synchronizationerror.

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2012 Using New Technologies for Public Parking in Isfahan City

Authors: M. Ahmadi Baseri, R. Mokhtari Malekabadi, A. Gandomkar

Abstract:

Cities expansion, urban travels increase, the technology development, the automobile price cheapen, and the families' income ascending cause the considerable increase in automobile numbers of the city. This fact has led to the traffic creation and the automobile parking site shortage in the city. Also in Esfahan metropolis, the parking lots shortage has been the great problem of this town; in addition, in designing and constructing of the parking sites the traditional methods are utilized which do not have a reasonable and optimized usage of the valuable urban lands. In this article, by introducing the prefabricate mechanized parking system which is inexpensive, simple and quick, and occupies very small space, therefore provides the high content of parking site for the cities, we can eliminate the parking space shortage difficulty of the cities. The achieved results of this research represent that an optimized utilization of the existent urban spaces for parking site construction has not been accomplished. By employing the new parking site technologies such as mechanization categorized parking sites and the capacity prefabricate mechanized of each parking space have become 8 multiples; in this case, the valuable urban lands can be used in an optimized way.

Keywords: Public parking sites, New parking sites technologies, Prefabricate mechanized parking site, Isfahan City.

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2011 Thermal Performance and Environmental Assessment of Evaporative Cooling Systems: Case of Mina Valley, Saudi Arabia

Authors: A. Alharbi, R. Boukhanouf, T. Habeebullah, H. Ibrahim

Abstract:

This paper presents a detailed description of evaporative cooling systems used for space cooling in Mina Valley, Saudi Arabia. The thermal performance and environmental impact of the evaporative coolers were evaluated. It was found that the evaporative cooling systems used for space cooling in pilgrims’ accommodations and in the train stations could reduce energy consumption by as much as 75% and cut carbon dioxide emission by 78% compared to traditional vapour compression systems.

Keywords: Evaporative cooling, vapour compression, electricity consumption and CO2 emission.

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2010 Strategic Redesign of Public Spaces with a Sustainable Approach: Case Study of Parque Huancavilca, Guayaquil

Authors: Juan Carlos Briones Macias

Abstract:

Currently, the Huancavilca City Park in Guayaquil is an abandoned public space that is discovering a growing problem of insecurity, where various problems have been perceived, such as the lack of green areas, deteriorating furniture, insufficient lighting, the use of inadequate cladding materials and very sunny areas due to the lack of planning in the design of green areas. The objective of this scientific article is to redesign Huancavilca Park through public space design strategies for more attractive and comfortable areas, becoming a point of interaction in a safe and accessible way. A mixed methodology (qualitative and quantitative) was applied, obtaining information based on surveys, interviews, field observations, and systematizing the data in the traditional weighting of the structuring aspects of the park. The results were obtained from the methodological design scheme of iterative analysis of public spaces by Jan Güell. It is concluded that the use of urban strategies in the structuring elements of the park, such as vegetation, furniture, generating new activities, and security interventions, will specifically solve all the problems of the Huancavilca Park tested in a Pareto 80/20 Diagram.

Keywords: Public space, green areas, vegetation, street furniture, urban analysis.

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2009 Evaluation of Japanese Kyoto Park in Terms of User Satisfaction

Authors: Ruhugül Özge Gemici

Abstract:

The need for open space, which is an important problem especially since the 19th century, has become more important in today's conditions. The most important factor in increasing the livability of cities is the open and green areas. Parks are the most important of the urban open and green space elements that provide the most benefit to users. In this context, the user satisfaction of the Japanese Kyoto Park, which is the subject of the research, was evaluated in the light of the questionnaires. With this analysis, the satisfaction level of the user using the park was determined. Suggestions have been developed for the park to be handled and regulated according to the user requests and requirements changing over time.

Keywords: Japanese park, landscape, landscape design, open and green areas.

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2008 A Robust Frequency Offset Estimation Scheme for OFDM System with Cyclic Delay Diversity

Authors: Won-Jae Shin, Young-Hwan You

Abstract:

Cyclic delay diversity (CDD) is a simple technique to intentionally increase frequency selectivity of channels for orthogonal frequency division multiplexing (OFDM).This paper proposes a residual carrier frequency offset (RFO) estimation scheme for OFDMbased broadcasting system using CDD. In order to improve the RFO estimation, this paper addresses a decision scheme of the amount of cyclic delay and pilot pattern used to estimate the RFO. By computer simulation, the proposed estimator is shown to benefit form propoerly chosen delay parameter and perform robustly.

Keywords: OFDM, cyclic delay diversity, FM system, synchronization

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2007 Modal Dynamic Analysis of a Mechanism with Deformable Elements from an Oil Pump Unit Structure

Authors: N. Dumitru, S. Dumitru, C. Copilusi, N. Ploscaru

Abstract:

On this research, experimental analyses have been performed in order to determine the oil pump mechanism dynamics and stability from an oil unit mechanical structure. The experimental tests were focused on the vibrations which occur inside of the rod element during functionality of the oil pump unit. The oil pump mechanism dynamic parameters were measured and also determined through numerical computations. Entire research is based on the oil pump unit mechanical system virtual prototyping. For a complete analysis of the mechanism, the frequency dynamic response was identified, mainly for the mechanism driven element, based on two methods: processing and virtual simulations with MSC Adams aid and experimental analysis. In fact, through this research, a complete methodology is presented where numerical simulations of a mechanism with deformed elements are developed on a dynamic mode and these can be correlated with experimental tests.

Keywords: Modal dynamic analysis, oil pump, vibrations, flexible elements, frequency response.

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2006 Cost-Effective Design of Space Structures Joints: A Review

Authors: Mohammed I. Ali, Feng Fan, Peter N. Khakina, Ma H.H

Abstract:

In construction of any structure, the aesthetic and utility values should be considered in such a way as to make the structure cost-effective. Most structures are composed of elements and joints which are very critical in any skeletal space structure because they majorly determine the performance of the structure. In early times, most space structures were constructed using rigid joints which had the advantage of better performing structures as compared to pin-jointed structures but with the disadvantage of requiring all the construction work to be done on site. The discovery of semi-rigid joints now enables connections to be prefabricated and quickly assembled on site while maintaining good performance. In this paper, cost-effective is discussed basing on strength of connectors at the joints, buckling of joints and overall structure, and the effect of initial geometrical imperfections. Several existing joints are reviewed by classifying them into categories and discussing where they are most suited and how they perform structurally. Also, finite element modeling using ABAQUS is done to determine the buckling behavior. It is observed that some joints are more economical than others. The rise to span ratio and imperfections are also found to affect the buckling of the structures. Based on these, general principles that guide the design of cost-effective joints and structures are discussed.

Keywords: Buckling, Connectors, Joint stiffness, Eccentricity, Second moment of area, Semi-rigid joints.

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2005 Using Gaussian Process in Wind Power Forecasting

Authors: Hacene Benkhoula, Mohamed Badreddine Benabdella, Hamid Bouzeboudja, Abderrahmane Asraoui

Abstract:

The wind is a random variable difficult to master, for this, we developed a mathematical and statistical methods enable to modeling and forecast wind power. Gaussian Processes (GP) is one of the most widely used families of stochastic processes for modeling dependent data observed over time, or space or time and space. GP is an underlying process formed by unrecognized operator’s uses to solve a problem. The purpose of this paper is to present how to forecast wind power by using the GP. The Gaussian process method for forecasting are presented. To validate the presented approach, a simulation under the MATLAB environment has been given.

Keywords: Forecasting, Gaussian process, modeling, wind power.

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2004 Selective Sulfidation of Copper, Zinc and Nickelin Plating Wastewater using Calcium Sulfide

Authors: K. Soya, N. Mihara, D. Kuchar, M. Kubota, H. Matsuda, T. Fukuta

Abstract:

The present work is concerned with sulfidation of Cu, Zn and Ni containing plating wastewater with CaS. The sulfidation experiments were carried out at a room temperature by adding solid CaS to simulated metal solution containing either single-metal of Ni, Zn and Cu, or Ni-Zn-Cu mixture. At first, the experiments were conducted without pH adjustment and it was found that the complete sulfidation of Zn and Ni was achieved at an equimolar ratio of CaS to a particular metal. However, in the case of Cu, a complete copper sulfidation was achieved at CaS to Cu molar ratio of about 2. In the case of the selective sulfidation, a simulated plating solution containing Cu, Zn and Ni at the concentration of 100 mg/dm3 was treated with CaS under various pH conditions. As a result, selective precipitation of metal sulfides was achieved by a sulfidation treatment at different pH values. Further, the precipitation agents of NaOH, Na2S and CaS were compared in terms of the average specific filtration resistance and compressibility coefficients of metal sulfide slurry. Consequently, based on the lowest filtration parameters of the produced metal sulfides, it was concluded that CaS was the most effective precipitation agent for separation and recovery of Cu, Zn and Ni.

Keywords: Calcium sulfide, Plating Wastewater, Filtrationcharacteristics, Heavy metals, Sulfidation.

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2003 Effects of LED Lighting on Visual Comfort with Respect to the Reading Task

Authors: Ayşe Nihan Avcı, İpek Memikoğlu

Abstract:

Lighting systems in interior architecture need to be designed according to the function of the space, the type of task within the space, user comfort and needs. Desired and comfortable lighting levels increase task efficiency. When natural lighting is inadequate in a space, artificial lighting is additionally used to support the level of light. With the technological developments, the characteristics of light are being researched comprehensively and several business segments have focused on its qualitative and quantitative characteristics. These studies have increased awareness and usage of artificial lighting systems and researchers have investigated the effects of lighting on physical and psychological aspects of human in various ways. The aim of this study is to research the effects of illuminance levels of LED lighting on user visual comfort. Eighty participants from the Department of Interior Architecture of Çankaya University participated in three lighting scenarios consisting of 200 lux, 500 lux and 800 lux that are created with LED lighting. Each lighting scenario is evaluated according to six visual comfort criteria in which a reading task is performed. The results of the study indicated that LED lighting with three different illuminance levels affect visual comfort in different ways. The results are limited to the participants and questions that are attended and used in this study.

Keywords: Illuminance levels, LED lighting, reading task, visual comfort criteria.

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2002 Improved Skin Detection Using Colour Space and Texture

Authors: Medjram Sofiane, Babahenini Mohamed Chaouki, Mohamed Benali Yamina

Abstract:

Skin detection is an important task for computer vision systems. A good method of skin detection means a good and successful result of the system. The colour is a good descriptor for image segmentation and classification; it allows detecting skin colour in the images. The lighting changes and the objects that have a colour similar than skin colour make the operation of skin detection difficult. In this paper, we proposed a method using the YCbCr colour space for skin detection and lighting effects elimination, then we use the information of texture to eliminate the false regions detected by the YCbCr skin model.

Keywords: Skin detection, YCbCr, GLCM, Texture, Human skin.

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2001 Further the Effectiveness of Software Testability Measure

Authors: Liang Zhao, Feng Wang, Bo Deng, Bo Yang

Abstract:

Software testability is proposed to address the problem of increasing cost of test and the quality of software. Testability measure provides a quantified way to denote the testability of software. Since 1990s, many testability measure models are proposed to address the problem. By discussing the contradiction between domain testability and domain range ratio (DRR), a new testability measure, semantic fault distance, is proposed. Its validity is discussed.

Keywords: Software testability, DRR, Domain testability.

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2000 Interpolation Issue in PVNPG-14M Application for Technical Control of Artillery Fire

Authors: Martin Blaha, Ladislav Potužák, Daniel Holesz

Abstract:

This paper focused on application support for technical control of artillery units – PVNPG-14M, especially on interpolation issue. Artillery units of the Army of the Czech Republic, reflecting the current global security neighborhood, can be used outside the Czech Republic. The paper presents principles, evolution and calculation in the process of complete preparation. The paper presents expertise using of application of current artillery communication and information system and suggests the perspective future system. The paper also presents problems in process of complete preparing of fire especially problems in permanently information (firing table) and calculated values. The paper presents problems of current artillery communication and information system and suggests requirements of the future system.

Keywords: Fire for effect, application, fire control, interpolation method, software development.

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1999 A Low-Cost Vision-Based Unmanned Aerial System for Extremely Low-Light GPS-Denied Navigation and Thermal Imaging

Authors: Chang Liu, John Nash, Stephen D. Prior

Abstract:

This paper presents the design and implementation details of a complete unmanned aerial system (UAS) based on commercial-off-the-shelf (COTS) components, focusing on safety, security, search and rescue scenarios in GPS-denied environments. In particular, The aerial platform is capable of semi-autonomously navigating through extremely low-light, GPS-denied indoor environments based on onboard sensors only, including a downward-facing optical flow camera. Besides, an additional low-cost payload camera system is developed to stream both infra-red video and visible light video to a ground station in real-time, for the purpose of detecting sign of life and hidden humans. The total cost of the complete system is estimated to be $1150, and the effectiveness of the system has been tested and validated in practical scenarios.

Keywords: Unmanned aerial system, commercial-off-the-shelf, extremely low-light, GPS-denied, optical flow, infrared video.

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1998 Sparse Coding Based Classification of Electrocardiography Signals Using Data-Driven Complete Dictionary Learning

Authors: Fuad Noman, Sh-Hussain Salleh, Chee-Ming Ting, Hadri Hussain, Syed Rasul

Abstract:

In this paper, a data-driven dictionary approach is proposed for the automatic detection and classification of cardiovascular abnormalities. Electrocardiography (ECG) signal is represented by the trained complete dictionaries that contain prototypes or atoms to avoid the limitations of pre-defined dictionaries. The data-driven trained dictionaries simply take the ECG signal as input rather than extracting features to study the set of parameters that yield the most descriptive dictionary. The approach inherently learns the complicated morphological changes in ECG waveform, which is then used to improve the classification. The classification performance was evaluated with ECG data under two different preprocessing environments. In the first category, QT-database is baseline drift corrected with notch filter and it filters the 60 Hz power line noise. In the second category, the data are further filtered using fast moving average smoother. The experimental results on QT database confirm that our proposed algorithm shows a classification accuracy of 92%.

Keywords: Electrocardiogram, dictionary learning, sparse coding, classification.

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1997 Decentralised Edge Authentication in the Industrial Enterprise IoT Space

Authors: C. P. Autry, A.W. Roscoe

Abstract:

Authentication protocols based on public key infrastructure (PKI) and trusted third party (TTP) are no longer adequate for industrial scale IoT networks thanks to issues such as low compute and power availability, the use of widely distributed and commercial off-the-shelf (COTS) systems, and the increasingly sophisticated attackers and attacks we now have to counter. For example, there is increasing concern about nation-state-based interference and future quantum computing capability. We have examined this space from first principles and have developed several approaches to group and point-to-point authentication for IoT that do not depend on the use of a centralised client-server model. We emphasise the use of quantum resistant primitives such as strong cryptographic hashing and the use multi-factor authentication.

Keywords: Authentication, enterprise IoT cybersecurity, public key infrastructure, trusted third party.

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1996 Application of Artificial Neural Network to Forecast Actual Cost of a Project to Improve Earned Value Management System

Authors: Seyed Hossein Iranmanesh, Mansoureh Zarezadeh

Abstract:

This paper presents an application of Artificial Neural Network (ANN) to forecast actual cost of a project based on the earned value management system (EVMS). For this purpose, some projects randomly selected based on the standard data set , and it is produced necessary progress data such as actual cost ,actual percent complete , baseline cost and percent complete for five periods of project. Then an ANN with five inputs and five outputs and one hidden layer is trained to produce forecasted actual costs. The comparison between real and forecasted data show better performance based on the Mean Absolute Percentage Error (MAPE) criterion. This approach could be applicable to better forecasting the project cost and result in decreasing the risk of project cost overrun, and therefore it is beneficial for planning preventive actions.

Keywords: Earned Value Management System (EVMS), Artificial Neural Network (ANN), Estimate At Completion, Forecasting Methods, Project Performance Measurement.

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1995 Numerical Grid Generation of Oceanic Model for the Andaman Sea

Authors: Nitima Aschariyaphotha, Pratan Sakkaplangkul, Anirut Luadsong

Abstract:

The study of the Andaman Sea can be studied by using the oceanic model; therefore the grid covering the study area should be generated. This research aims to generate grid covering the Andaman Sea, situated between longitudes 90◦E to 101◦E and latitudes 1◦N to 18◦N. A horizontal grid is an orthogonal curvilinear with 87 × 217 grid points. The methods used in this study are cubic spline and bilinear interpolations. The boundary grid points are generated by spline interpolation while the interior grid points have to be specified by bilinear interpolation method. A vertical grid is sigma coordinate with 15 layers of water column.

Keywords: Sigma Coordinate, Curvilinear Coordinate, AndamanSea.

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1994 Pronominal Anaphora Processing

Authors: Anna Maria Di Sciullo

Abstract:

Discourse pronominal anaphora resolution must be part of any efficient information processing systems, since the reference of a pronoun is dependent on an antecedent located in the discourse. Contrary to knowledge-poor approaches, this paper shows that syntax-semantic relations are basic in pronominal anaphora resolution. The identification of quantified expressions to which pronouns can be anaphorically related provides further evidence that pronominal anaphora is based on domains of interpretation where asymmetric agreement holds.

Keywords: asymmetric agreement, pronominal anaphora, quantifiers and indefinite expressions.

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1993 Parameter Estimation of Diode Circuit Using Extended Kalman Filter

Authors: Amit Kumar Gautam, Sudipta Majumdar

Abstract:

This paper presents parameter estimation of a single-phase rectifier using extended Kalman filter (EKF). The state space model has been obtained using Kirchhoff’s current law (KCL) and Kirchhoff’s voltage law (KVL). The capacitor voltage and diode current of the circuit have been estimated using EKF. Simulation results validate the better accuracy of the proposed method as compared to the least mean square method (LMS). Further, EKF has the advantage that it can be used for nonlinear systems.

Keywords: Extended Kalman filter, parameter estimation, single phase rectifier, state space modelling.

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1992 A Completed Adaptive De-mixing Algorithm on Stiefel Manifold for ICA

Authors: Jianwei Wu

Abstract:

Based on the one-bit-matching principle and by turning the de-mixing matrix into an orthogonal matrix via certain normalization, Ma et al proposed a one-bit-matching learning algorithm on the Stiefel manifold for independent component analysis [8]. But this algorithm is not adaptive. In this paper, an algorithm which can extract kurtosis and its sign of each independent source component directly from observation data is firstly introduced.With the algorithm , the one-bit-matching learning algorithm is revised, so that it can make the blind separation on the Stiefel manifold implemented completely in the adaptive mode in the framework of natural gradient.

Keywords: Independent component analysis, kurtosis, Stiefel manifold, super-gaussians or sub-gaussians.

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1991 Performances Assessment of Direct Torque Controlled IM Drives Using Fuzzy Logic Control and Space Vector Modulation Strategy

Authors: L. Moussaoui, L. Rahmani

Abstract:

This paper deals with the direct torque control (DTC) of the induction motor. This type of control allows decoupling control between the flux and the torque without the need for a transformation of coordinates. However, as with other hysteresis-based systems, the classical DTC scheme represents a high ripple, in both the electromagnetic torque and the stator flux and a distortion in the stator current. As well, it suffers from variable switching frequency. To solve these problems various modifications, in conventional DTC scheme, have been made during the last decade. Indeed the DTC based on space vector modulation (SVM) has proved to generate very low ripples in torque and flux with constant switching frequency. It also shows almost the same dynamic performances as the classical DTC system. On the other hand, fuzzy logic is considered as an interesting alternative approach for its advantages: Analysis close to the exigencies of user, ability of nonlinear systems control, best dynamic performances and inherent quality of robustness.

Therefore, two fuzzy direct torque control approaches, for the induction motor fed by SVM-voltage source inverter, are proposed in this paper. By using these two approaches of DTC, the advantages of fuzzy logic control, space vector modulation, and direct torque control method are combined. The performances of these DTC schemes are evaluated through digital simulation using Matlab/Simulink platform and fuzzy logic tools. Simulation results illustrate the effectiveness and the superiority of the proposed Fuzzy DTC-SVM schemes in comparison to the classical DTC.

Keywords: Direct torque control, Fuzzy logic control, Induction motor, Switching frequency, Space vector modulation, Torque and flux ripples.

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1990 Multi-level Metadata Integration System: XML, RDF and RuleML

Authors: Messaouda Fareh, Omar Boussaid, Rachid Challal

Abstract:

Our work is part of the heterogeneous data integration, with the definition of a structural and semantic mediation model. Our aim is to propose architecture for the heterogeneous sources metadata mediation, represented by XML, RDF and RuleML models, providing to the user the metadata transparency. This, by including data structures, of natures fundamentally different, and allowing the decomposition of a query involving multiple sources, to queries specific to these sources, then recompose the result.

Keywords: Mediator, Metadata, Query, RDF, RuleML, XML, Xquery.

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1989 Restructuring of XML Documents in the Form of Ontologies

Authors: Jamal Bakkas, Mohamed Bahaj, Abdellatif Soklabi

Abstract:

The intense use of the web has made it a very changing environment, its content is in permanent evolution to adapt to the demands. The standards have accompanied this evolution by passing from standards that regroup data with their presentations without any structuring such as HTML, to standards that separate both and give more importance to the structural aspect of the content such as XML standard and its derivatives. Currently, with the appearance of the Semantic Web, ontologies become increasingly present on the web and standards that allow their representations as OWL and RDF/RDFS begin to gain momentum. This paper provided an automatic method that converts XML schema document to ontologies represented in OWL.

Keywords: XML Schema, OWL, RDB, Mapping, Ontology.

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1988 Dynamic State Estimation with Optimal PMU and Conventional Measurements for Complete Observability

Authors: M. Ravindra, R. Srinivasa Rao

Abstract:

This paper presents a Generalized Binary Integer Linear Programming (GBILP) method for optimal allocation of Phasor Measurement Units (PMUs) and to generate Dynamic State Estimation (DSE) solution with complete observability. The GBILP method is formulated with Zero Injection Bus (ZIB) constraints to reduce the number of locations for placement of PMUs in the case of normal and single line contingency. The integration of PMU and conventional measurements is modeled in DSE process to estimate accurate states of the system. To estimate the dynamic behavior of the power system with proposed method, load change up to 40% considered at a bus in the power system network. The proposed DSE method is compared with traditional Weighted Least Squares (WLS) state estimation method in presence of load changes to show the impact of PMU measurements. MATLAB simulations are carried out on IEEE 14, 30, 57, and 118 bus systems to prove the validity of the proposed approach.

Keywords: Observability, phasor measurement units, PMU, state estimation, dynamic state estimation, SCADA measurements, zero injection bus.

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1987 Transient Currents in a Double Conductor Line above a Conducting Half-Space

Authors: Valentina Koliskina, Inta Volodko

Abstract:

Transient eddy current problem is solved in the present paper by the method of the Laplace transform for the case of a double conductor line located parallel to a conducting half-space. The Fourier sine and cosine integral transforms are used in order to find the Laplace transform of the solution. The inverse Laplace transform of the solution is found in closed form. The integrated electromotive force per unit length of the double conductor line is calculated in the form of an improper integral.

Keywords: Transient eddy currents, Laplace transform, double conductor line.

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