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5th International Conference on Concept Lattices and Their Applications, CLA 2007

作者： Belohlavek, Radim De Baets, Bernard Outrata, Jan Vychodil, Vilem Dept. Systems Science and Industrial Engineering T.J. Watson School of Engineering and Applied Science SUNY Binghamton PO Box 6000 Binghamton NY 13902-6000 United States Dept. Appl. Math. Biometrics and Process Control Ghent University Coupure links 653 B-9000 Gent Belgium Dept. Computer Science Palacky University Olomouc Tomkova 40 CZ-779 00 Olomouc Czech Republic

The paper presents a new method of decision tree induction based on formal concept analysis (FCA). The decision tree is derived using a concept lattice, i.e. a hierarchy of clusters provided by FCA. The idea behind is to look at a concept lattice as a collection of overlapping trees. The main purpose of the paper is to explore the possibility of using FCA in the problem of decision tree induction. We present our method and provide comparisons with selected methods of decision tree induction on testing datasets.

关键词： Formal concept analysis

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Using Requirements Management Tools in Software Product Line engineering: The State of the Practice

Using Requirements Management Tools in Software Product Line...

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International Software Product Line Conference (SPLC)

作者： Danilo Beuche Andreas Birk Heinrich Dreier Andreas Fleischmann Heidi Galle Gerald Heller Dirk Janzen Isabel John Ramin Tavakoli Kolagari Thomas von der Massen Andreas Wolfram Pure-systems GmbH Magdeburg Germany Software Process Management Stuttgart Germany SynSpace Freiburg im Breisgau Germany Software and Systems Engineering Group Technical University Munich Garching Germany Automotive Systems Division Continental Markdorf Germany Hewlett Packard Company Boblingen Germany Harman/Becker Automotive Systems GmbH Karlsbad Germany Fraunhofer IESE Kaiserslautern Germany Software Engineering Group Technical University Berlin Berlin Germany Arvato direct services GmbH Gutersloh Germany

A software product line oriented approach to developing systems has an impact on the development process as a whole. Although the basic idea of product lines is simple, systematic implementation of the approach is a challenging task. In fact, today's software product lines have such complex variability that their handling must be supported by tools, otherwise a systematic approach would not be possible. The same holds for requirements management of product lines. On the basis of specific industrial scenarios the paper derives important requirements that have to be observed if requirements management tools are to be usefully applied to product lines. Current requirements management tools are evaluated on the basis of these requirements in their daily industrial use. The presented requirements can indicate the future direction of tool development and method research.

关键词： engineering management Software tools Automotive engineering Product development Environmental management Project management Conference management Software development management Software systems systems engineering and theory

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A Scheme of EDTC control using a Three-Level Voltage Source Inverter for an Induction Motor

A Scheme of EDTC Control using a Three-Level Voltage Source ...

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2007 IEEE International Symposium on Industrial Electronics (ISIE 2007), vol.6

作者： R. Zaimeddine E. M. Berkouk L. Refoufi M. Bousalah Department of Electrical Engineering 'Signals and Systems' Research laboratory University of M'hamed Bougara Boumerdes Algeria Process Control Laboratory National Polytechnic School Algiers Algeria

The object of this paper is to study a new control structure for sensorless induction machine dedicated to electrical drives using a three-level voltage source inverter (VSI). The amplitude and the rotating speed of the flux vector can be controlled freely. Both fast torque response and optimal switching logic can be achieved;the selection is based on the value of the stator flux and the torque. A novel DTC scheme of induction motors is proposed in order to develop a suitable dynamic. We propose an approach;in which we enhance the response of torque and flux with optimal switching strategies. However, the middle point voltage of the input DC voltages of the three-level NPC voltage source inverter presents serious problems caused by a fluctuation of the DC voltage sources U{sub}(cU), U{sub}(cL). As consequence to these problems, we obtain an output voltage of the inverter which is asymmetric and with an average value different from zero. In this paper, we will present one solution to minimise this fluctuation. This solution uses a clamping bridge to regulate the input voltages of a three-level inverter VSI NPC. A scheme of Enhanced direct torque control "EDTC" with complete cascade is simulated for an induction motor. The results obtained indicate superior performance over the FOC one without need to any mechanical sensor.

关键词： Induction motor Direct torque control Fast torque response Sensorless vector control Voltage source inverter Field oriented control Flux estimators Switching strategy optimisation Neutral-point clamped

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PMU placement method based on decoupled newton power flow and sensitivity analysis

PMU placement method based on decoupled newton power flow an...

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International Conference on Electrical Power Quality and Utilisation (EPQU)

作者： G. Mueller P. Komarnicki I. Golub Z. Styczynski C. Dzienis J. Blumschein Fraunhofer Institute for Factory Operation and Automation IFF Process and Plant Engineering Business Unit Magdeburg Germany Chair of Electric Power Networks and Renewable Energy Sources Otto von Guericke University Magdeburg Magdeburg Germany Chair of Electric Power Networks Energy Systems Institute Russian Academy of Science Irkutsk Russia Power Transmission and Distribution Energy Automation Division Siemens AG Germany

Complex power systems need more observability in critical situations. Synchron phasor measurement is a new technology that improves power supply reliability and quality. PMU measure various system parameters extremely precisely and rapidly. Every PMU measurement receives a GPS synchronized time stamp, thus making it possible to perform precise comparative analyses and obtain an overview of the complete system. Since system operators have to work economically and these units and their installation incur costs, they need an algorithm for their optimal placement. This paper presents a concept based on a decoupled Newton-Raphson power flow analysis and a sensitivity analysis, which helps place PMU optimally. The theory behind the algorithm is elucidated and results of a system test are presented.

关键词： Phasor measurement units Load flow Sensitivity analysis Power system reliability Power system analysis computing Power system measurements Observability Power measurement Power supplies Time measurement

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Thermal energy reservoirs from processed lunar regolith

Thermal energy reservoirs from processed lunar regolith

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5th International Energy Conversion engineering Conference

作者： Wegeng, Robert S. Mankins, John C. Taylor, Lawrence A. Sanders, G.B. Batteile Memorial Institute Pacific Northwest National Laboratory United States Artemisinnovation Management Solutions Earth and Planetary Sciences Department University of Tennessee United States National Aeronautics and Space Administration Johnson Space Center United States Process Science and Engineering Department Pacific Northwest National Laboratory P.O. Box 999 Richland WA 99352 United States ArtemisInnovation Management Solutions 43446 Thistlewood Court Ashburn VA 20147 United States Planetary Geosciences Institute Department of Earth and Planetary Sciences University of Tennessee Knoxville TN 37996 United States Energy Systems Division NASA Johnson Space Center Mail Code EP 2101 NASA Road 1 Houston TX 77058 United States

ISBN: (纸本)1563479028

NASA's plan for returning to the Moon includes the early establishment of a human outpost, where energy and power will be at a premium, particularly during the lunar night. To permit occupation during the full lunar 27-day diurnal cycle, energy storage will be required. The use of engineered, Thermal Energy Reservoirs (TERs) is one of several energy-storage options. While actual lunar regolith is a poor thermal-mass material, it can readily be processed to yield improved thermophysical properties. Establishing the ability to produce thermal-mass materials from lunar regolith reduces the cost of bringing energystorage materials from Earth and provides a source of heat and supplemental electrical power during periods of darkness. This paper discusses methods of producing thermal-mass materials from lunar regolith, engineering concepts for lunar TERs, and system configurations that could provide heat and electricity. This paper also includes the results of preliminary calculations, bounding the potentials and limitations of lunar TERs.

关键词： Reservoirs (water)

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Traceable nanonewton force measurement at the National Physical Laboratory, UK 6

Traceable nanonewton force measurement at the National Physi...

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6th International Conference European Society for Precision engineering and Nanotechnology, EUSPEN 2006

作者： Leach, R.K. Oldfield, S. Georgakopoulos, D. Engineering and Process Control Division National Physical Laboratory United Kingdom

ISBN: (纸本)0955308208

The National Physical Laboratory (NPL), UK, has recently developed an instrument for the traceable measurement of low forces aimed at the demands of micro- and nanotechnology industries. These industries require that traceable force measurements be made in the range of piconewtons to micronewtons. The newly developed instrument addresses the force range from 1 nN to 10 μN. In operation an unknown force is applied to a dielectric blade that is constrained to move between, and parallel to, the surface of two pairs of electrically conducting plates. An electrostatic force on the dielectric, that is equal and opposite to the applied force, is generated by applying a potential difference to the conducting plates via a null servo system. This paper describes the basic design and initial testing of the instrument.

关键词： Force measurement

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Case studies in modelling large scale complex process and biomedical systems

Case studies in modelling large scale complex process and bi...

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1st IFAC Workshop on Applications of Large Scale Industrial systems, ALSIS'06

作者： Linkens, D.A. Department of Automatic Control and Systems Engineering Institute for Microstructural and Mechanical Process Engineering University of Sheffield United Kingdom

ISBN: (纸本)9783902661159

Complexity occurs throughout every level of the natural ***, the challenge is to attempt to understand,analyse, represent and model some aspects of such *** ultimate aim is to design complex systems in a principled and reliable *** this presentation two case studies are *** concerns the modelling of metal processing hot deformation down to sub-micron dislocation *** second study considers the analysis of biological microarray data of huge input dimensionality coupled with sparse data for the likely prediction of human bladder cancer.

关键词： Deformation

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Overview of catalyst management and selection protocols at Saudi Aramco's refineries

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Saudi Aramco Journal of Technology 2006年第FALL期 11-16页

作者： Al-Alloush, Saeed S. Yeh, Gene Aitani, Abdullah M. Downstream Process Engineering Division Saudi Aramco Process and Control Systems Department Saudi Arabia Catalytic Conversion Unit Saudi Aramco Process and Control Systems Department Saudi Arabia Dhahran Saudi Arabia

Catalysts play an important role in producing valuable products from crude oil. A discussion covers an overview of catalyst management at Saudi Aramco's refineries;selection protocols stated in the firm's engineering Standard, SAES-A-207;use of catalysts in basic refining processes, e.g., naphtha reforming, FCC, hydrocracking/desulfurization, isomerization, and hydrogen production;measuring catalyst performance;and case example.

关键词： Catalysts

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Abrasion and toughness property maps for WC/Co hardmetals

Abrasion and toughness property maps for WC/Co hardmetals

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European Powder Metallurgy Congress and Exhibition, Euro PM 2006

作者： Roebuck, B. Gant, A.G. Gee, M.G. Materials Centre Division of Engineering and Process Control National Physical Laboratory Teddington MiddlesexTW11 0LW United Kingdom

WC/Co hardmetals are generally designed to be used in applications where wear resistance, particularly abrasion or erosion, needs to be high but without the association of low toughness often found in very hard materials. Consequently, mapping the relation between wear characteristics and toughness is fundamental to the process of grade selection in commercial hardmetals. In the current research wear resistance has been assessed using the ASTM B611 abrasion test method and toughness through Palmqvist fracture toughness. Both these tests are now well understood, especially the uncertainties associated with the measurements, and can be used with confidence in mapping properties. There are two main types of property map;those concerned with comparing properties associated with end use, e.g. abrasion and toughness, and those concerned with relating microstructural parameters to the property of interest i.e. abrasion and its dependence on WC grain size. Both of these types of map are considered in the paper together with comments on the effects of changing WC grain size distribution as well as changing WC mean grain size. © Euro PM 2006 - Powder Metallurgy Congress and Exhibition. All rights reserved.

关键词： Abrasion

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CASE STUDIES IN MODELLING LARGE SCALE COMPLEX process AND BIOMEDICAL systems

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IFAC Proceedings Volumes 2006年第14期39卷 1-10页

作者： D A Linkens IMMPETUS Institute for Microstructural and Mechanical Process Engineering: The University of Sheffield Department of Automatic Control and Systems Engineering University of Sheffield UK

Complexity occurs throughout every level of the natural world. Technologically, the challenge is to attempt to understand, analyse, represent and model some aspects of such complexity. The ultimate aim is to design complex systems in a principled and reliable manner. In this presentation two case studies are considered. One concerns the modelling of metal processing hot deformation down to sub-micron dislocation levels. The second study considers the analysis of biological microarray data of huge input dimensionality coupled with sparse data for the likely prediction of human bladder cancer.

关键词： multi-scale modelling metal deformation genomics bioinformatics cellular automata finite elements neurofuzzy

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