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Multifunction Numerical control Solution for Hybrid Mechanic and Laser Machine Tool

Procedia CIRP 2012年 1卷 260-264页

作者： Georgi M. Martinov Aleksandr B. Ljubimov Anton S. Grigoriev Lilija I. Martinova Department of Computer-architecture Control System Moscow State Technological University STANKIN Vadkovsky per. 1 Moscow 127994 Russia Department of Production Engineering Moscow State Technological University “STANKIN” Vadkovsky per. 1 Moscow 127994 Russia

Hybrid and also multitasking machine tools are equipped with a multifunction NC system. The popularity of multitasking machines is growing because of the decrease of the necessity to use manufacturing equipment and the reduction of the workpiece refixturing during processing. Hybrid machines provide a more efficient and productive manner of processing with the help of simultaneous and controlled interaction processes by the mechanisms and (or) energy sources. Equipment, which combines machining of parts and laser hardening of their surfaces, is becoming increasingly popular among machine builders as well as it replaces effectively a number of finishing operations to ensure the quality of surface. But the implementation of the hybrid solution is restricted not only from the HMI part, but mostly from the architecture of the control system. The control system laser treatment has its own specifics, so it should be integrated into the overall structure of machine tool as a standalone module. А solution for mechanical cutting and laser treatment on the basis of external interpolation module is implemented in such a way that according to the target solution can be performed simultaneously or separately. On completion of machining the part program switches on a laser for laser hardening. The control system turns off the built-in interpolator and forwards the data to the external interpolation module, the switching procedure is completely transparent to the operator. The paper illustrates the concept and design aspects of the CNC system architecture.

关键词： CNC for hybrid machine tool laser structured surface external interpolation module

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The relationship between diagnostic coverage and proof test interval for 1002 and 1002D architectures

The relationship between diagnostic coverage and proof test ...

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13th IFAC Symposium on control in Transportation systems, CTS 2012

作者： Üstoǧlu, Ilker Kaymakçi, Özgür T. Börcsök, Josef Yildiz Technical University Davutpaşa Campus A209 34220 34220 Esenler Istanbul Turkey Yildiz Technical University Davutpaşa Campus A210 34220 34220 Esenler Istanbul Turkey University Kassel Faculty of Electrical Engineering / Computer Science Department of Computer Architecture and System Programming Wilhelmshöher Allee 71 34121 Kassel Germany

ISBN: (纸本)9783902823137

In order to measure the effectiveness of safety protection systems there are several design parameters. Diagnostic coverage factor is one of the most important parameter which influences all architectures. In this short paper the relationship between PFDavg, DC and TI are presented. 1002 and 1002D architectures are considered as examples. © 2012 IFAC.

关键词： architecture

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Stability analysis of a photovoltaic grid connected inverter model based on system identification

Stability analysis of a photovoltaic grid connected inverter...

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IEEE Region 10 International Conference TENCON

作者： Nopporn Patcharaprakiti Krissanapong Kirtikara Anawach Sanswang Sudchai Boonto Department of Electrical and Computer Rajamangala University of Technology Lanna Department of Electrical Engineering Department of Control System and Instrumentation Engineering King Mongkut's University of Technology Bangkok Thailand

ISBN: (纸本)9781467348232

This paper presents a system stability analysis of a grid-connected inverter from a linear system viewpoint. A Photovoltaic (PV) inverter model is derived using a system identification method, specifically the Hammerstein-Wiener model. The PV inverter is supplied by a controllable DC power supply and the inverter output is connected to a 220 V utility grid. The input and output characteristics on the inverter terminals are collected and the nonlinear model of the inverter is obtained. The inverter model is decomposed into three parts follow as nonlinear input, linear middle part and nonlinear output. Both nonlinear parts are deemed static where the dynamical behavior is described by the middle part. The stability of the inverter is analyzed based on a linearized model of the nonlinear system. Frequency response analysis is performed for insight on the system dynamical behavior.

关键词： Power system stability Stability criteria Inverters Mathematical model system identification Thermal stability

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Automatic segmentation of brain tumors in magnetic resonance images

Automatic segmentation of brain tumors in magnetic resonance...

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IEEE-EMBS International Conference on Biomedical and Health Informatics, BHI 2012. In Conj. with the 8th Int. Symp.on Medical Devices and Biosensors and the 7th Int. Symp. on Biomedical and Health engineering

作者： Behzadfar, Neda Soltanian-Zadeh, Hamid Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran 14395-515 Iran Pooyandegan Rah Saadat Company Tehran 16756-965 Iran Image Analysis Laboratory Radiology Department HenryFord Healh System Detroit MI 48202 United States

ISBN: (纸本)9781457721779

Segmentation of tumors in magnetic resonance images (MRI) is an important task but is quite time consuming when performed manually by experts. Automating this process is challenging due to the high diversity in appearance of tumor tissue in different patients, and in many cases, similarity between tumor and normal tissues. This paper presents an automatic method for segmentation of brain tumors in MRI. We use images of patients with glioblastoma multiform tumors. After pre-processing and removal of the regions that do not have useful information (e.g., eyes and scalp), we create a projection image for determining the primary location of the tumor. This image provides an overall view of the tumor. Then, we grow the primary region to segment the entire tumor. This method is automatic and independent of the operator. It segments low contrast tumors without requiring their exacta tissue boundaries. The segmentation results obtained by the proposed approach are compared with those of an expert radiologist showing excellent correlations among them (R2=0.97). © 2012 IEEE.

关键词： Tumors

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Treatment of Missing Data in Intelligent Lighting Applications

Treatment of Missing Data in Intelligent Lighting Applicatio...

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Symposia and Workshops on Ubiquitous, Autonomic and Trusted Computing, UIC-ATC

作者： Aravind Kota Gopalakrishna Tanir Özçelebi Antonio Liotta Johan J. Lukkien System Architecture and Networking (SAN) Department of Mathematics and Computer Science Eindhoven University of Technology The Netherlands Electro-Optical Communications Department of Electrical Engineering Eindhoven University of Technology The Netherlands

The concept of intelligent lighting facilitates the use of machine learning models to adapt the lighting application behavior based on changing context. Ideally, a complete dataset without missing values is used to train the learning algorithm. Nevertheless, it is common to have missing data values in the dataset, e.g. due to lack of rich enough user interfaces such as smart phones. In this paper, we study various probabilistic approaches to treat missing feature values in a dataset collected from an office breakout area. This dataset is used to train the learning model to provide intelligent lighting solutions. We evaluate the performance of five different approaches by simulation, using four rule-based classification algorithms and various proportions of missing data. We find that none of these approaches gives best performance over the necessary range of conditions, and that an adaptive strategy is more suited.

关键词： Lighting Probabilistic logic Training Data models Computational modeling Adaptation models Smart phones

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Distributed Cooperative Tracking for Multiple Second-order Nonlinear systems Using Only Relative Position Measurements

Distributed Cooperative Tracking for Multiple Second-order N...

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The 24th Chinese control and Decision Conference (第24届中国控制与决策学术年会 2012 CCDC)

作者： Ziyang Meng Zongli Lin Department of Automation Shanghai Jiao Tong University and KeyLaboratory of System Control and Inf Charles L. Brown Department of Electrical and Computer Engineering University of Virginia Charlott

In this paper, a distributed cooperative tracking problem is studied for a group of second-order nonlinear systems. The control goal is to drive the states of the followers to converge to those of a time-varying leader using only relative information. We focus on the case of the output feedback, where the velocities of the followers and the leader are not available. Two kinds of distributed observers are proposed for the cases when the follower dynamics are uniformly globally exponentially stable and the follower dynamics are continuously differentiable, respectively. Using the observer outputs, we design the control inputs such that the distributed cooperative tracking problem of multiple second-order nonlinear systems is solved under the constraint that only relative position measurements are available. Simulations are given to validate the theoretical results.

关键词： networked second-order nonlinear systems output feedback continuously differentiable

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Scalable Open Cross-Platform Kernel of PCNC system for Multi-Axis Machine Tool

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Procedia CIRP 2012年 1卷 238-243页

作者： Sergej N. Grigoriev Georgi M. Martinov Department of High-effective Machining Technologies State Technological University “STANKIN” Vadkovsky per. 1 Moscow 127994 Russia Department of Computer-architecture Control System Moscow State Technological University “STANKIN” Vadkovsky per. 1 Moscow 127994 Russia

Creating the basis of numerical control is demanded by ensuring the invariance of the applied solution, reducing the development cycle and preserving investments made in software development through cross-platform solution for real-time, the component approach and code reusing. Open architecture is implemented with the help of allocating the levels of abstraction in the CNC kernel, which provides transparence kernel algorithms according to the specifics of the hardware solution, the flow program language version, and the way of implementing the operator interface. The paper illustrates the approach of the invariant CNC kernel layout and the scaling of the control channels inside the pipeline data processing, according to the multi-axis machine requirements. The prospects of development in the direction of using web-technologies and creating remote terminals for controlling, monitoring and adjusting machine tools are defined. The right choice of the control system architecture reduces the interpolation and PLC cycle time, which is the determining factor in the high-speed cutting for multi-axis machine tools. It results in reducing data processing time in CNC enhance the manufacturing performance.

关键词： CNC system with open modular architecture pipeline processing of a flow program remote terminal

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Design of multiple anti-windup loops for multiple activations

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Science China(Information Sciences) 2012年第9期55卷 1925-1934页

作者： WU XiongJun 1,2 & LIN Zongli 3,1 1 department of Automation,Shanghai Jiao Tong University,and Key Laboratory of system control and Information Processing,Ministry of Education of China,Shanghai 200240,China 2 No.802 Institute of Shanghai Academy of Space Flight Technology,the Eighth Academy of China Aerospace Science and Technology Corporation,Shanghai 200090,China 3 Charles L.Brown department of Electrical and computer engineering,University of Virginia,P.O.Box 400743,Charlottesville,VA 22904-4743,USA 1. Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai 200240 China2. No. 802 Institute of Shanghai Academy of Space Flight Technology the Eighth Academy of China Aerospace Science and Technology Corporation Shanghai 200090 China3. Charles L. Brown Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 Charlottesville VA 22904-4743 USA

This paper considers anti-windup design for linear systems subject to actuator *** anti-windup gains are designed for activations immediately at the occurrence actuator saturation,after the saturation has reached a certain level and in anticipation of the occurrence of saturation,*** design is based on the minimization of L 2 gain from the disturbance to the controlled output of the resulting closed-loop *** anti-windup scheme involves a single anti-windup loop for immediate activation.A recent innovation is to design a single anti-windup loop for delayed or anticipatory activation,as well as to design two anti-windup gains,one for immediate activation and one for delayed *** design of three anti-windup gains for three different activations is shown through simulation to lead to significant further performance improvement over the previous activation schemes.

关键词： actuator saturation anti-windup anticipatory activation delayed activation L 2 gain nonlinear control

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Power system restoration planning and some key issues

Power system restoration planning and some key issues

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IEEE General Meeting Power& Energy Society

作者： John N. Jiang Zuping Zhang Mingtian Fan Greg Harrison Chenxi Lin Maria Tamayo Varun Perumalla School of Electrical and Computer Engineering University of Oklahama USA Power System Research Department China Electric Power Research Institute China CEPRI Brazil Electric power engineering in the School of Electrical and Computer Engineering University of Oklahama USA Control system and power engineering University of Oklahama USA Alstom Grid USA

ISBN: (纸本)9781467327275

Improving the effectiveness of power system restoration planning becomes more important, since a higher NERC standard will be implemented in the near future. Standard EOP-005-2 concerns about the increased risk of large-scale system blackout due to the increased degree of uncertainty, as a very likely consequence of dynamic market activities, integration of large-scale less-dispatchable energy resources and other factors threatening the power system security. This paper presents a discussion of some of the important planning issues for power system restoration following a large-scale blackout. These issues were raised from several system restoration planning projects completed by the authors for several utility companies in Central United States and South China. Current practices at these companies are summarized. In addition, some bottleneck problems in effective restoration planning and possible solutions are suggested.

关键词： Planning Companies Power system stability Generators Transient analysis Reliability

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Voxel-based treatment prediction of glioblastoma multiform tumor using diffusion tensor imaging

Voxel-based treatment prediction of glioblastoma multiform t...

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作者： Sabahi, Hadi Soltanian-Zadeh, Hamid Scarpace, Lisa Mikkelsen, Tom Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran 14395-515 Iran Image Analysis Laboratory Radiology Department Henry Ford Hospital Detroit MI 48202 United States Hermelin Brain Tumor Research Center Neurosurgery Department Henry Ford Health System Detroit MI 48202 United States

ISBN: (纸本)9781457721779

This paper proposes a method to predict the effect of Bevacizumab therapy on Glioblastoma Multiform (GBM) tumors. The prediction is critical for effective treatment planning. The proposed method is developed and evaluated using Diffusion Tensor Imaging (DTI) and post-contrast T1-weighted Magnetic Resonance Images (pc-T1-MRI) of 14 patients with GBM tumors gathered before and after the treatment. First, the proposed method calculates diffusion anisotropy indices (DAI) of all voxels in the brain. These diffusion anisotropy indices are Fractional Anisotropy (FA), Mean Diffusivity (MD), Relative Anisotropy (RA), and Volume Ratio (VR). Then, it registers post-treatment pc-T1-MRI and pre-treatment DAI maps to pre-treatment pc-T1-MRI. Next, it uses a thresholding method to segment the tumor from pc-T1-MRI studies. Comparing Gd-enhanced voxels of the pre- and post-treatment pc-T1-MRI, the DAIs of the tumor are labeled based on their response to the treatment. The voxels of 7 patients are randomly selected to train 4 classifiers (ANN, SVM, KNN, and ANFIS) and then all voxels of the other 7 patients are used to test them. For each classifier, four performance measures (sensitivity, specificity, positive predictive value, and accuracy) are calculated. Experimental results show that the ANFIS is more accurate than the other classifiers in predicting the treatment response. © 2012 IEEE.

关键词： Tumors

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