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Inert effects on the flammability characteristics of methanol by nitrogen or carbon dioxide

Journal of Thermal Analysis and Calorimetry 2009年第3期96卷 759-763页

作者： Chiang, C.-C. Lee, J.-C. Chang, Y.-M. Chuang, C.-F. Shu, C.-M. 1 Jin-De Rd. Changhua Changhua 50074 Taiwan Department of Electrical Engineering Hsiuping Institute of Technology 11 Gong-Ye Rd. Dali Taichung 41280 Taiwan Doctoral Program Graduate School of Engineering Science and Technology National Yunlin University of Science and Technology 123 University Rd. Sec. 3 Douliou Yunlin 64002 Taiwan Bao-Shan Campus 1 Jin-De Rd. Changhua Changhua 50074 Taiwan

Knowledge of material safety properties is critical for safe handing in the chemical process industries, especially for flammable chemicals that might result in serious fires and explosions. This study investigated the flammability characteristics of methanol under working conditions during the process. The targeted fire and explosion properties, like explosion limits (UEL and LEL), vapor deflagration index (K g), maximum explosion pressure (P max), and maximum explosion pressure rise [(dP dt -1) max], were deliberately obtained via a 20-L-Apparatus in 101 kPa (i.e., 760 mmHg/1 atm), 150 and 200 °C, along with various experimental arrangements containing nitrogen (N2) or carbon dioxide (CO 2) as inert component. Particularly, this study discussed and elucidated the inert influence on the above safety-related parameters by two different inerting gases of N2 and CO2. The results indicated that adding an inert component to fuel-inert gas mixtures determined the decrease of explosion range and flammability hazard degree. The results also demonstrated that CO2 possessed higher inerting capability than N2 in this study. © 2009 Akadémiai Kiadó, Budapest, Hungary.

关键词： Carbon dioxide

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Statistical method with efficient IT support for power transformer asset management

Statistical method with efficient IT support for power trans...

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International Conference on electrical engineering/Electronics, Computer, Telecommunications and Information Technology, ECTI-CON

作者： Cattareeya Suwanasri Thanapong Suwanasri Faculty of Engineering Naresuan University Phitsanulok Thailand Electrical Power Program Sirindhorn International Thai German Graduate School of Engineering King Mongkut's University of Technology North Bangkok Thailand

Power transformer has degraded under its normal and abnormal operating conditions, maintenance activities are vital to restore the condition back to the normal condition. The traditional preventive maintenance is well known and successfully performed, but its cost is very high. This paper aims to improve the drawback by introducing asset management system for systematical records of scattering failure statistics. Web application is used to support a condition evaluation of power transformer. To determine a criticality of each component, a statistic method as Weibull distribution is proposed. Power transformer models of rated voltages 115/22 kV and 230/115 kV are applied based on available technical data, history test records and number in service. Finally, failure results, lifetime estimations and mean time between failures of power transformer components are discovered. Subsequently, data collection and analysis as well as appropriate maintenance planning are systematically managed.

关键词： Statistical analysis Power transformers Asset management Statistical distributions Degradation Power system restoration Preventive maintenance Costs Scattering Weibull distribution

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Improved and modified geometric formulation of POE based kinematic calibration of serial robots

Improved and modified geometric formulation of POE based kin...

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2009 IEEE/RSJ International Conference on Intelligent Robots and Systems

作者： Yunjiang Lou Tieniu Chen Yuanqing Wu Zhibin Li Shilong Jiang Division of Control and Mechatronics Engineering Shenzhen Graduate School Harbin Institute of Technology Shenzhen China School of Mechanical Engineering Shanghai Jiaotong University Shanghai China Division of Control and Mechatronics Engineering Shenzhen Graduate School Harbin Institute of Technology Shenzhen China School of Mechanical and Electrical Engineering Shenzhen Polytechnic College China Postdoctoral Research Center of Harbin Institute of Technology Harbin and Googol Technology Limited Shenzhen China

The authors proposed in this paper an improved geometric formulation of POE (product of exponential) based kinematic calibration of serial robots. We use both joint offset-free formulation and adjoint transformation errors of joint screws, and apply it to the calibration of an elbow manipulator. Our formulation explains why the original POE calibration always fails with the existence of joint offset errors; the adjoint formulation of joint screw errors eliminates joint screw constraints that was imposed in the original iterated least square calibration algorithm. The second contribution of this paper is the proposal of a modified POE formulation which adopts point measurement data instead of frame measurement data of the end-effector, which can be more realistic and convenient for practical implementation. Simulation results show that the proposed method is plausible and effective. An experiment is under preparation to verify the effectiveness of the proposed calibration method on an elbow manipulator built by Googol Technology.

关键词： Calibration Robot kinematics Fasteners Solid modeling Intelligent robots Manipulators Robotic assembly Mechatronics Elbow Error correction

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Numerical Simulation of a DNA Sensor Based on the CNT-Gold Island Structure

Numerical Simulation of a DNA Sensor Based on the CNT-Gold I...

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International Workshop on Computational Electronics

作者： Gyu-sik Choe Jun-Myung Woo Young June Park Young Wook Chang Jeseung Oh Kyung-Hwa Yoo School of Electrical Engineering and Nano-Systems Institute(NSI-NCRC) Seoul National University Seoul South Korea Department of physics and Nanomedical graduate program Yonsei University Seoul South Korea

ISBN: (纸本)9781424439256

A numerical simulation has been performed for the DNA sensors based on the field-effect-transistor (FET) structure of a CNT with the gold island- attached on the CNT tube. The model uses the Poisson-drift-diffusion theory for the CNT transistor and considers the charge exchange between the interfaces between the CNT and gold island, gold and the linker molecules. In order to compare with experiments, an example device is simulated to predict the response of the sensor to the target DNA's in both the air and aqueous solution.

关键词： Numerical simulation DNA Gold FETs Joining processes Boundary conditions Electrostatics Poisson equations Charge carrier processes Electrodes

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Dimension reduction for hyperspectral image classification via support vector based feature extraction

Dimension reduction for hyperspectral image classification v...

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2008 IEEE International Geoscience and Remote Sensing Symposium - Proceedings

作者： Cheng-Hsuan, Li Bor-Chen, Kuo Chin-Teng, Lin Chih-Cheng, Hung Department of Electrical and Control Engineering National Chiao Tung University China Graduate School of Educational Measurement and Statistics National Taichung University China Southern Polytechnic State University Marietta GA 30067 United States

ISBN: (纸本)9781424428083

Usually feature extraction is applied for dimension reduction in hyperspectral data classification problems. Many studies show that nonparametric weighted feature extraction (NWFE) is a powerful tool for extracting hyperspectral image features. The detection of class boundaries is an important part in NWFE and the weighted mean was defined for this purpose. In this paper, a kernelbased feature extraction is proposed based on a new class boundary detection mechanism. The soft-margin support vector machine (SVM) binary classifier and the support vector domain description (SVDD) are applied to detect the boundaries between two classes and one class, respectively. The results of real data experiments show that the proposed method outperforms original NWFE. © 2008 IEEE.

关键词： Support vector machines

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Design of fuzzy controller for automatic steering

Design of fuzzy controller for automatic steering

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作者： Ko, Sang-Jin Lee, Jun-Woo Choi, Byoung-Suk Lee, Ju-Jang Graduate School of Automobile Technology KAIST Daejeon Korea Republic of Robotics Program KAIST Daejeon Korea Republic of Department of Electrical Engineering and Computer Science KAIST Daejeon Korea Republic of

ISBN: (纸本)9784990288020

Unmanned vehicle is future vehicle technology. Lateral control technology and longitudinal control technology are needed for unmanned vehicle. Automatic steering system is lateral control technology. A automatic steering system automatically controls the steering to keep the vehicle in its land and also to follow the lane as it curves around. This paper proposes automatic steering system based on fuzzy logic. If the fuzzy rules are set properly, the fuzzy controller can control the objective system nicely. To design an automatic steering system, lateral error dynamics of a vehicle is derived. The proposed automatic steering system is evaluated by SIMULINK in MATLAB. The simulation results show that the proposed automatic steering system works satisfactorily for keeping the vehicle in its land and following the lane. ©ISAROB 2008.

关键词： Fuzzy control

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Combined Effect of Inter-Path Interference Cancellation And Random Transmit Power Control on DS-CDMA Packet Mobile Communications

Combined Effect of Inter-Path Interference Cancellation And ...

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IEEE Conference on Vehicular Technology (VTC)

作者： Eisuke Kudoh Haruki Ito ZhiSen Wang Fumiyuki Adachi Department of Electrical and Communication Engineering Graduate School of Engineering University of Tohoku Sendai Japan School of Information Science and Engineering Dalian Polytechnic University Dalian China

In mobile communication systems, high speed packet data services are demanded. In the high speed data transmission, throughput degrades severely due to severe inter-path interference (IPI). Recently, we proposed a random transmit power control (TPC) to increase the up link throughput of DS- CDMA packet mobile communications. In this paper, we apply IPI cancellation in addition to the random TPC. We derive the numerical expression of the received signal-to-interference plus noise power ratio (SINR) and introduce IPI cancellation factor. Then we evaluate, by Monte-Carlo numerical computation method, the combined effect of random TPC and IPI cancellation on the uplink throughput of DS-CDMA packet mobile communications.

关键词： Interference cancellation Power control Multiaccess communication Mobile communication Throughput Signal to noise ratio Data engineering Power engineering and energy Noise cancellation Degradation

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Cathodoluminescence study on spatial luminescence properties of InN/GaN multiple quantum wells consisting of 1-monolayer-thick InN wells/GaN matrix

Cathodoluminescence study on spatial luminescence properties...

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作者： Hwang, E.S. Che, S.B. Saito, H. Wang, X. Ishitani, Y. Yoshikawa, A. Graduate School of Electrical and Electronics Engineering Chiba University Chiba 263-8522 Japan InN-Project CREST-program of JST Chiba University Chiba 263-8522 Japan VBL Chiba University Chiba 263-8522 Japan

Spatially resolved luminescence properties of InN/GaN multiple quantum wells (MQWs) consisting of nominally one monolayer (1-ML)-thick InN QWs embedded in a GaN matrix are studied by cross-sectional and plan-view cathodoluminescence measurements. First it is confirmed that the dominant emission peaks observed at around 390 nm to 430 nm in the MQWs samples are attributed to the effects of inserting ˜ 1-ML-thick InN wells in the GaN matrix, resulting in efficient localization of GaN excitons at InN QWs. Furthermore, it is revealed that the detailed structure of the MQWs, such as the thickness distribution and interface sharpness, is very sensitive to the presence of surface defects such as hillocks around screw-component threading dislocations, resulting in different emission wavelengths/energies. This is because the epitaxy process for depositing such thin InN wells is seriously affected by the atomic-level surface structures/properties of the growth front. It will be concluded that it is necessary to use lower dislocation density GaN bulk templates to obtain much higher structural quality InN/GaN MQWs good enough for characterizing their optical properties. © 2007 TMS.

关键词： Semiconductor quantum wells

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Application of Optical Flow Field for Intelligent Tracking System

Application of Optical Flow Field for Intelligent Tracking S...

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International Symposium on Intelligent Information Technology Application, IITA

作者： Yupeng Xia Xin Wang Feng Hu School of Mechanical and Electrical Engineering Shenzhen Polytechnic Shenzhen Guangdong China Shenzhen Graduate School Harbin Institute of Technology Shenzhen Guangdong China

In order to make the data responding to the edges of moving objects expand to the area, whose gray level is flat, it needs to keep iterative numbers large enough on gradient-based optical flow algorithm. The traditional approaches need a large amount of calculation, but results accuracy is low. The gradient number accuracy and reliability will directly determine the result of optical flow algorithm. In the hope of improving numerical reliability of image gradient data, we have used four methods to manage gradient number effectively, which are Hessian matrix distinguishing, Gaussian filtering standard deviation amending, mean model amending and multi-image comparing. The four algorithms mentioned above were applied to tracking contours and segmentation of car images on the traffic scene. From the experimental results, it is shown that both the calculation convergence speed and accuracy of our methods have greatly improved compared with traditional algorithms, the feasibility and validity of those methods were confirmed.

关键词： Image motion analysis Intelligent systems Optical filters Iterative algorithms Accuracy Filtering Image segmentation Traffic control Layout Convergence

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Electromagnetic interferences caused by power line communications in the HF bands

Electromagnetic interferences caused by power line communica...

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IEEE International Symposium on Power Line Communications and Its Applications (ISPLC)

作者： Joong-Geun Rhee Eugene Rhee Jee-Sik Park Department of Electronic Electrical Control and Instrumentation Engineering Hanyang University Seoul South Korea Graduate school of Knowledge-basedTechnology and Energy Polytechnic University South Korea

With little cost and quick installation time by using existing power line networks, power line communication (PLC) is a very promising high-speed data communication techniques. However, as carrier frequency band of a PLC increases for high speed services, there arise many concerns about the possibility of its electromagnetic interferences or disturbances to the nearby other equipments. This paper introduces the latest status of electromagnetic interference standards of PLC in Korea and presents the measurement results of radiated and conducted emissions in the HF spectrum from a PLC modem. The measurement was done at AM radio band and amateur radio communication bands. These measurement results were compared with radiated and conducted electromagnetic emission limits specified in the Rules on radio wave in Korea.

关键词： Electromagnetic interference Power line communications programmable control Electromagnetic measurements Electromagnetic radiation Costs Data communication Frequency Electromagnetic radiative interference Measurement standards

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