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Annual Conference of Industrial Electronics Society

作者： J. Kwon W. Yang H. Kim Y. Oh J.-H. Bae H.-d. Kang School of Robotics Kwangwoon Univ. Seoul Korea Central Advanced Research & Engineering Institute Hyundai Motor Company Seoul Korea Center for Robotics Research Korea Institute of Sci. & Tech. Seoul Korea Robotics R&D Group Korea Institute of Indus. Tech. Ansan Korea School of Life Science Ulsan National Institute of Science and Technology Ulsan Korea

While the central pattern generator (CPG) controller based on biologically inspired neural oscillator networks is known to achieve repeatability and entrainment of rhythmic output motion, no systematic approach to implement the controller has been provided so far. In this study a series of schemes are introduced to tune the control parameters and to set up the network coupling of artificial neural oscillators combined with the virtual force control. Application of the schemes to the proposed controller for a three-link planar robot arm demonstrates that the optimized controller with proper neural oscillator networks can produce minimize the energy consumption with an enhanced-entrained motion with the change of a desired motion and interaction of unknown environments.

关键词： Oscillators Manipulators Neural networks Neurons robot sensing systems Couplings

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Highly efficient InGaN/GaN blue LEd grown on Si (111) substrate

Highly efficient InGaN/GaN blue LED grown on Si (111) substr...

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Conference on Lasers and Electro-Optics (CLEO)

作者： Jun-Youn Kim Yongjo Tak Jae Won Lee Hyun-Gi Hong Suhee Chae Hyoji Choi Bokki Min Youngsoo Park Minho Kim Seongsuk Lee Namgoo Cha Yoonhee Shin Jong-ryeol Kim Jong-In Shim Photo-Electronic Device Group Semiconductor Device Lab Samsung Advanced Institute of Technology (SA1T) Suwon Republic of Korea Research and Development 2Team Samsung LED Company Limited Suwon South Korea R&D 2Team Samsung LED) Suwon Republic of Korea Department of Optical Engineering Sejong University Seoul Republic of Korea Department of Electrical and Computer Engineering Hanyang University Ansan Republic of Korea

ISBN: (纸本)9781557529107

For the first time, based on the high crystalline quality of n-GaN on Si template, highly efficient InGaN/GaN LEds grown on 4-inch silicon substrates comparable to those on sapphire substrates have been successfully demonstrated. At driving current of 350 mA, the overall output power of 1 × 1 mm 2 LEd chips exceeded 420 mW and forward voltage was 3.2 V under un-encapsulated condition, which is the best value among the reported values of blue LEd grown on Si substrates. The internal quantum efficiency of 76% at injection current of 350 mAwas measured.

关键词： Silicon Substrates Light emitting diodes Gallium nitride Epitaxial growth Power generation Semiconductor device measurement

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Optimal utilization of frequency ancillary services in modern power systems

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e-Prime - Advances in Electrical engineering, Electronics and Energy 2024年 9卷

作者： Ullah, Kaleem Ullah, Zahid Basit, Abdul Gruosso, Giambattista US-Pakistan Center for Advanced Studies in Energy University of Engineering and Technology Peshawar Peshawar 25000 Pakistan Dipartimento di Elettronica Informazione e Bioingegneria Politecnico di Milano Piazza Leonardo Da Vinci 32 Milan 20133 Italy Manager R&D National Power Control Center National Transmission and Dispatch Company Islamabad 44000 Pakistan

The widespread global adoption of wind energy sources has established a significant presence in the existing power grid. However, the massive integration of intermittent wind energy poses forecasting errors, prompting the need for supplementary reserves from conventional energy sources with increased operational expenses and carbon emissions. Hence, to facilitate the seamless operation of large-scale wind-integrated power grids, it is imperative to harness the potential of renewable energy sources and leverage flexible loads to deliver power-balancing services. In this research, dynamic real-time power dispatch strategies have been developed for the Automatic Generation Control (AGC) system to integrate the reserve capacities of conventional generation units and wind power plants and utilize the demand response capabilities of flexible loads for power balancing services. A comprehensive power system grid model was developed in digSilent PowerFactory software, consisting of coal-based energy systems, wind energy systems, gas turbines, and cold storage units as flexible loads. The study is divided into different case studies to assess the impact of each scenario on system operation in mitigating the forecasting errors of wind power plants. Further, a comparative analysis was performed to illustrate the effectiveness of each case study. The analysis showed that Case Study III, where reserves are provided by coal energy systems and cold storage units, yielded the highest reduction in Positive regulation (Pr) and Negative regulation (Nr) errors, at 89.0% and 94.15%, respectively. Conversely, Case Study IV demonstrated the least reduction in errors, with 67.82% in Pr and 78.41% in Nr. However, it indicates that reserves can be supplied from wind energy systems and flexible loads without the support of conventional power plants. © 2024 The Author(s)

关键词： and Automatic Generation Control Coal-based Energy Systems Frequency regulation Power dispatch Strategies Wind Energy Systems

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Bottom Hole Pressure Calculation of Fractured Carbonate Formation

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IOP Conference Series: Earth and Environmental Science 2020年第2期570卷

作者： Yichi Zhang Jin Yang Wei Liu Mu Li Zhenxiang Zhang Xin Zhao College of Safety and Ocean Engineering China University of Petroleum (Beijing) Beijing 102249 China. CNPT Engineering Technology R&D Company Limited Beijing 102206 China.

Carbonate formation is widely distributed in China, mainly showing the sensitivity of the target formation and the development of fracture and cavity types and narrow pressure window. drilling complicated conditions such as formation leakage or bottom hole pressure less than formation pressure due to gas entering wellbore occur from time to time. To solve these problems, calculating the bottom hole pressure accurately and conducting managed pressure drilling (MPd) for fractured carbonate formation are necessary. In this study, the single-phase hydraulic model based on H-B rheological model is calculated. According to the characteristics of fractured carbonate formation, the drilling fluid leakage model is obtained. By coupling the leakage model with the single-phase wellbore hydraulic model, the bottom hole pressure calculation method is suitable for fractured carbonate formation, which can provide reference for managed pressure control drilling technology. Such a technology is verified by Bozhong X well through the above calculation method of bottom hole pressure. The model is used to simulate the leakage behavior of transverse and longitudinal fractures. Moreover, the variation characteristics of the leakage rate and cumulative leakage amount of the drilling fluid in the fracture are investigated. By comparing the loss control with conventional drilling and MPd, the advantages of controlled pressure drilling operation in the loss control are described.

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Investigation on Erosion resistance of downhole Throttle with Ultra-high Pressure

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IOP Conference Series: Earth and Environmental Science 2020年第1期453卷

作者： Huiyun Ma Yuan Jiang Qiang Yin Fangfang Zhang Shaowei Chen Yanxin Lv Guoping Lei Engineering Technology Research Institute PetroChina Southwest Oil & Gas Field Company Chengdu Sichuan 610017 China National Energy R&D Center of High Sulfur Gas Exploitation Chengdu Sichuan 610017 China CNPC Chuanqing Drilling Engineering Company Limited Guanghan Sichuan 618300 China School of Mechatronic Engineering Southwest Petroleum University Chengdu Sichuan 610500 China

The throttling nozzle, the core element of downhole throttling tool, is seriously eroded in the producing-sand gas well. In this paper, the fixed downhole throttle developed by Petro China Southwest Oil and Gasfield company is taken as the research object, and the flow state of gas and the movement of sand particles are expressed by rNG k – ε model and dPM model respectively. Through Fluent numerical simulation, the internal flow field distribution rule of throttle with diameter of 70mm is discussed, the most serious erosion area of throttle is obtained, and the influence of solid particle velocity, solid particle diameter and solid particle mass flow rate on the erosion of throttle are analyzed. It is meaningful to design and improve throttle according to working parameters of gas well. According to the simulation, it is believed that the fixed downhole throttle will contribute to a better understanding for erosion resistance of downhole throttle with ultra-high pressure.

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Optimum design of downhole chokes with high sulfur content and large pressure difference

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IOP Conference Series: Earth and Environmental Science 2020年第1期461卷

作者： Ma Huiyun Jiang Yuan Yin Qiang Zhang Fangfang Chen Shaowei Lv Yanxin Lei Guoping Engineering Technology Research Institute PetroChina Southwest Oil & Gas Field Company Chengdu Sichuan 610017 China National Energy R&D Center of High Sulfur Gas Exploitation Chengdu Sichuan 610017 China CNPC Chuanqing Drilling Engineering Company Limited Guanghan Sichuan 618300 China School of Mechatronic Engineering Southwest Petroleum University Chengdu Sichuan 610500 China

Natural gas resources are abundant in southwest China, but the exploitation environment with high pressure and sulfur always affects the working performance of downhole chokes, which in turn restricts the output of natural gas. In this paper, a high sulfur resistance fixed downhole choke is designed for high temperature (120°C), high production rate and high pressure difference (105MPa) sand-producing Wells. Through the nozzle discharge model to simulate the flow of the fluid through the nozzle, with Bono Maleev method to predict the hydrate formation conditions of downhole choke for the design of the structure. According to the failure forms of different parts, the materials were optimized, and the high sulfur resistant 3YC51 alloy, hard alloy and wear and corrosion resistant sulfur resistant rubber were selected through the test to improve the service life of the choke in the high sulfur high-pressure gas well and ensure the reliability of the tool. The results of numerical analysis on the tool holder and the pressure test of the Laboratory seal show that the choke designed has a good sealing and pressurization performance in the high temperature and high pressure difference environment of 120°C and 105MPa, and it can realize the function of lowering the pressure at the bottom of the well under this working condition, meeting the feasibility requirements. Through this design, the design and improvement of high sulfur gas well tool and new choke has guiding significance.

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Correction to: Foliation Effects on Mechanical and Failure Characteristics of Slate in 3d Space Under Brazilian Test Conditions

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rock Mechanics and rock engineering 2021年第11期54卷 5963-5963页

作者： ding, Changdong Zhang, Yang Hu, dawei Zhou, Hui Shao, Jianfu State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China University of Chinese Academy of Sciences Beijing China University of Lille LaMcube CNRS FRE2016 Lille France CNPC Engineering Technology R&D Company Limited Beijing China

A correction to this paper has been published: https://***/10.1007/s00603-021-02460-9

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Progress report on failures of high voltage bushings with draw leads

Progress report on failures of high voltage bushings with dr...

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IEEE General Meeting Power& Energy Society

作者： Phil Hopkinson Arturo del rio Loren Wagenaar Jin Sim robert degeneff Larry Coffeen robert Ganser Thomas Tobin James McBride Enrique Betancourt Bjorn Lofgren School of Computer and Communication Engineering University of Science and Technology Beijing School of Information and Electronics Beijing Institute of Technology Beijing Photovoltaic and Wind Power systems Quality Test Center Chinese Academy of Sciences Beijing China New Energy Test Center Tibet Energy Research and Demonstration Center Tibet China Utility Systems Technologies Inc USA NEETRAC school of Electrical and Computer Engineering at the Georgia Institute of Technology USA State of Ohio USA R&D for S&C Electric Company USA JMX Services Inc. USA Prolec GE Germany Siemens Energy Jackson Mississippi USA

Over the past several years, several bushings equipped with draw leads have failed in service. These bushings are not isolated to a single manufacturer and all of them have passed standard routine and type tests. A common characteristic of each failure is the arcing marks found between the draw lead cable and the tube in the center of the bushing. Most of the bushings also failed violently, in that the bushing exploded and caused a fire. The purpose of this panel session paper is four fold: First, extensive investigations have already been conducted on aspects of certain failure mechanisms, and the findings will be reported. Second, other possible, but as yet uninvestigated, failure modes are given. Third, it is hoped this report will draw the interest of others in the industry who will add to the knowledge surrounding this subject. Fourth, suggestions are made to prevent or alleviate the problem. It is not known exactly what causes the arcing in the first place, but it is currently thought that it is initiated by a transient of some kind then is sustained by the power frequency service voltage. Possible transient generators and the ensuing failure mechanism are described.

关键词： Insulators Lead Electron tubes Transient analysis Power transformers Oil insulation Flanges

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Effects of dry and mist saunas on circulatory and thermoregulatory functions in humans

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Health 2013年第2期5卷 267-273页

作者： Satoshi Iwase Yuko Kawahara Naoki Nishimura Hiroki Takada Mayumi Nagata Yuki Niimi Chihiro Miwa Aichi Medical College for Physical Therapy and Occupational Therapy Kiyosu Japan Department of Human & Artificial Intelligent Systems Graduate School of Engineering University of Fukui Fukui Japan Department of Neurology Tsushima Municipal Hospital Tsushima Japan Department of Physiology Aichi Medical University Nagakute Japan Group of Home Systems & Appliance R&D Department of Home Systems & Appliance Sales Toho Gas Co. Ltd. Nagoya Japan Plumbing Fixtures Technology Research Institute Kitchen & Plumbing Fixtures Company LIXIL Corporation Tokoname Japan

To test the hypothesis that mist sauna is a safer way of bathing than dry sauna, we compared changes in circulatory and thermoregulatory functions during 10 min sauna bathing in mist sauna at 40℃ with relative humidity of 100%, and in dry sauna by infrared ray at 70℃ with relative humidity of 15%. Subjects were seven healthy young men aged 29 ± 6 yrs (mean ± Sd). We measured blood pressure, heart rate, skin temperatures at chest, forearm, thigh, and leg, tympanic temperature (Tty) by thermistors, skin blood flow at forearm by laser doppler flowmetry, and sweat rate by ventilated capsule method at 1 min intervals throughout the experiment. Total sweating and change of hematocrit were also measured for dehydration analysis. Blood pressure was elevated more and changes in heart rate and total sweating were larger in dry sauna than mist. A significant hematocrit increase was observed in dry sauna bathing only. Mean skin temperature and Tty in dry sauna were elevated higher than those in mist. Heat stress of the dry sauna may be stronger than that of the mist, leading to dehydration and hypovolemia by sweating. Percent plasma volume loss was significantly larger in the dry than mist sauna. Changes in skin blood flow and sweat rate/Tty during mist sauna were significantly larger than those during dry sauna bathing despite heat stress of the mist sauna. The mist sauna bathing may thus be safer physiologically, and provide more effective vascular dilatation and sweating than the dry sauna bathing.

关键词： Sauna Bathing Mist Sauna dry Sauna Heat Stress Hemodynamic Change Thermoregulatory Function

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Highly Active and Thermally robust Nickel Enolate Catalysts for the Synthesis of Ethylene-Acrylate Copolymers

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Angewandte Chemie 2022年第35期134卷

作者： Shuoyan Xiong Alexandria Hong Brad C. Bailey Heather A. Spinney Todd d. Senecal Hannah Bailey Theodor Agapie Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA Chemical Science Core R&D The Dow Chemical Company Midland MI 48667 USA

The insertion copolymerization of polar olefins and ethylene remains a significant challenge in part due to catalysts′ low activity and poor thermal stability. Herein we demonstrate a strategy toward addressing these obstacles through ligand design. Neutral nickel phosphine enolate catalysts with large phosphine substituents reaching the axial positions of Ni achieve activity of up to 7.7×10 3 kg mol −1 h −1 (efficiency >35×10 3 g copolymer/g Ni) at 110 °C, notable for ethylene/acrylate copolymerization. NMr analysis of resulting copolymers reveals highly linear microstructures with main-chain ester functionality. Structure-performance studies indicate a strong correlation between axial steric hindrance and catalyst performance.

关键词： Acrylate Catalysis Copolymers Nickel Olefins

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