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Development of HILS System for Performance Evaluation of a Heavy Commercial Vehicle Hybrid Electric Power Steering System (대형 상용차량 하이브리드 전동식 조향 시스템 주행 성능평가를 위한 HILS 시스템 개발)

  • Yoo, Chunsik;Choi, Gyoojae
    • Transactions of the Korean Society of Automotive Engineers
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    • v.25 no.1
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    • pp.103-110
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    • 2017
  • Most commercial vehicles have adopted the hydraulic power steering system. To reduce fuel consumption and to improve steering controllability, a hybrid electric power steering system is being developed for commercial vehicles. In this study, the HILS (Hardware In the Loop Simulation) system equipped with a commercial vehicle hybrid electric power steering system was developed and the vehicle dynamic performance of a truck with the steering system was evaluated. The hybrid electric power steering system is composed of the EHPS motor pump, column mounted EPS system, and ball nut steering gear box for heavy commercial vehicles. The accuracy of vehicle models equipped with the HILS system was verified with comparisons between the simulation results and field test results. The road reaction forces of the steering system were generated from the vehicle model and verified using field test results. Step steering tests using the verified HILS system were carried out and the performance of a newly developed commercial vehicle hybrid electric power steering system was evaluated.

Investigation of the semi-active electromagnetic damper

  • Montazeri-Gh, Morteza;Kavianipour, Omid
    • Smart Structures and Systems
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    • v.13 no.3
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    • pp.419-434
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    • 2014
  • In this paper, the electromagnetic damper (EMD), which is composed of a permanent-magnet rotary DC motor, a ball screw and a nut, is considered to be analyzed as a semi-active damper. The main objective pursued in the paper is to study the two degrees of freedom (DOF) model of the semi-active electromagnetic suspension system (SAEMSS) performance and energy regeneration controlled by on-off and continuous damping control strategies. The nonlinear equations of the SAEMSS must therefore be extracted. The effects of the EMD characteristics on ride comfort, handling performance and road holding for the passive electromagnetic suspension system (PEMSS) are first analyzed and damping control strategies effects on the SAEMSS performance and energy regeneration are investigated next. The results obtained from the simulation show that the SAEMSS provides better performance and more energy regeneration than the PEMSS. Moreover, the results reveal that the on-off hybrid control strategy leads to better performance in comparison with the continuous skyhook control strategy, however, the energy regeneration of the continuous skyhook control strategy is more than that of the on-off hybrid control strategy (except for on-off skyhook control strategy).

The Evaluation on the Effectiveness as a Cosmetic Material of Oil Extracted from Schizandra Chinensis Seed (오미자 씨 오일의 화장품 소재로서 유효성 평가)

  • Yang, Jae-Chan
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.2
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    • pp.231-237
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    • 2012
  • In order to use the Schizandra chinensis seed oil as a basic material of cosmetic component, the research was done by analyzed components of Schizandra chinensis seed oil and evaluation it's stability with GC and GC/MSD. As a result, it's main component were showed as palmitic acid and oleic acid. It has excellent stability because it's ingredients did not change under the heat. Also, the antioxidant effect used DPPH(1,1-Diphenyl-2-picrylhydrazyl) test method, indicated higher radical scavenging ability compare to widely-use macademia nut oil and olive oil. Collagen synthesis effect also appeared outstanding. Therefore, the Schizandra chinensis seed oil was determined that it has possibility to be used well for cosmetic material.

Robust Fuzzy Logic Current and Speed Controllers for Field-Oriented Induction Motor Drive

  • El-Sousy, Fayez F.M.;Nashed, Maged N.F.
    • Journal of Power Electronics
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    • v.3 no.2
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    • pp.115-123
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    • 2003
  • This paper presents analysis, design and simulation for the indirect field orientation control (IFOC) of induction machine drive system. The dynamic performance of the IFOC under nominal and detuned parameters of the induction machine is established. A conventional proportional plus integral-derivative (PI-D) two-degree-of-freedom controller (2DOFC) is designed and analysed for an ideal IFOC induction machine drive at nominal parameters with the desired dynamic response. Varying the induction machine parameters causes a degredation in the dynamic response for disturbance rejection and tracking performance with PI-D 2DOF speed controller. Therefore, conventional controllers can nut meet a wide range of speed tracking performance under parameter variations. To achieve high- dynamic performance, a proposed robust fuzzy logic controllers (RFLC) for d-axis rotor flux, d-q axis stator currents and rotor speed have been designed and analysed. These controllers provide robust tracking and disturbance rejection performance when detuning occurres and improve the dynamic behavior. The proposed REL controllers provide a fast and accurate dynamic response in tracking and disturbance rejection characteristics under parameter variations. Computer simulation results demonstrate the effectiveness of the proposed REL controllers and a robust performance is obtained fur IFOC induction machine drive system.

Time Constant Estimation and Compensation of Induction Motor rotor using Adaptive Fuzzy Controller (적응 퍼지제어기를 이용한 유도전동기 회전자의 시정수 추정 및 보상)

  • Lee Young-Sil;Lee Jung-Chul;Lee Hong-Gyun;Nam Su-Myeong;Kim Jong-Kwan;Chung Dong-Hwa
    • Proceedings of the KIPE Conference
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    • 2004.07a
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    • pp.42-45
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    • 2004
  • This paper is proposed an adaptive fuzzy controller of induction motor drive. The adaptive fuzzy controller approach for an estimate of the rotor time constant which is used to adjust the estimate of the slip angular speed. An estimate of the rotor time constant was obtained using an model reference adaptive system(MRAS) in a fuzzy control scheme. The rotor time constant was estimated by utilizing the rotor nut estimates. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new method.

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Studies on the Shape Optimization of Connecting Element for Hydro-Embedding (하이드로 임베딩시 체결용 연결요소의 형상 최적화 연구)

  • Kim B. J.;Kim D. K.;Kim D. J.;Moon Y. H.
    • Transactions of Materials Processing
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    • v.14 no.9 s.81
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    • pp.756-763
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    • 2005
  • The applicability and productivity of hydroforming process can be increased by combining pre- and post-forming processes such as the bending, piercing and embedding process. For the fabrication of automotive parts, the hollow bodies with connecting nuts are widely used to connect parts together. Hollow body with connecting nuts has been conventionally fabricated by welding nuts or screwing in autobody screws. It requires multiple steps and devices fur the welding and/or screwing Therefore in this study, hydro-embedding process that combines the hydraulic embedding of connecting element(nut) with hydroforming process is investigated. Studies on the hydro-embedding technology have been performed to optimize the shape of the connecting element by analyzing the deformed mode of the embedded tube The effects of the shape of the screw tip, screw thread and shape of thread on the connection force between the tube and the connecting element have been investigated to optimize the shape of connecting element. Finite element analysis has also been performed to provide deformation behaviors of the tube surrounding a hole produced by hydro-embedding.

A New Analog Switch CMOS Charge Pump Circuit without Body Effect

  • Parnklang, Jirawath;Manusphrom, Ampual;Laowanichpong, Nut;Tongnoi, Narongchai
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.212-214
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    • 2005
  • The charge-pump circuit which is used to generate higher voltage than the available supply voltage has wide applications such as the flash memory of EEPROM Because the demand for high voltage comes from physical mechanism such as the oxide tunneling, the required pumped voltage cannot be scaled as the power supply voltage is scaled. Therefore, an efficient charge-pump circuit that can achieve high voltage from the available low supply voltage is essential. A new Analog Switch p-well CMOS charge pump circuit without the MOS device body effect is processed. By improve the structure of the circuit's transistors to reduce the threshold voltage shift of the devices, the threshold voltage of the device is kept constant. So, the circuit electrical characteristics are higher output voltage within a shorter time than the conventional charge pump. The propose analog switch CMOS charge pump shows compatible performance of the ideal diode or Dickson charge pump.

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The Historical Study of Korean Traditional Funtional Food (한국의 전통적 기능성 식품의 이용에 대한 역사적 고찰)

  • 한복진
    • Journal of the East Asian Society of Dietary Life
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    • v.6 no.2
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    • pp.235-255
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    • 1996
  • Natural substances, exploited in our daily life, have been applied to drugs to treat diseases and developed to functional foods by appropriate preparations, and these foods give beneficial effects on physical activities. In this paper, the utilization of traditional functional foods was studied with refer ring to old ancient writings published in the front-end of Chosun dynasty. The utilized vegetables were march mallow, turnip, radish, Chinese cabbage, lettuce, spinach, cucumber winter buds, flesh of a cabbage, eggplant, taro, burdock, Parsley, watershield plant, crown daisy, bamboo shoots, garlic, scallion, onion, acorn, bark of a tree, white goosefoot leaf, leaf of bean, pine mushroom, bracken. yam, mugwort, tea, ginseng, peppermint, fruit of the Maximowiczia chinensis, smartweed and pepper. The utilized fruits were chestnut, Chinese date, pine nuts, walnut, gingko nut, citrus. crab apple, pear, peach, grape, pomegranate, plum, Chinese quince, fig and watermelon. The utilized cereal were rice, barley, bean, buckweat and Job's-tears. The utilized sweetenings and seasonings were honey, wheat-gluten, sugar, oil, salt, soy sauce and vinegar. Our ancestors had a balanced diet using the various foods, and especially had a fundamental concept of "Foods have the efficacy of a remedy".edy".uot;.

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Constituents Released from Streptococcus mutans Attenuate Arecoline-mediated Cytotoxicity in HGF Cells by Altering Intracellular $Ca^{2+}$ Signaling

  • Erkhembaatar, Munkhsoyol;Oh, Hyuncheol;Kim, Min Seuk
    • International Journal of Oral Biology
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    • v.39 no.1
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    • pp.41-47
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    • 2014
  • Streptococcus mutans (S. mutans) is a facultative anaerobic bacterium mainly found in the oral cavity and is known to contribute to tooth decay and gingivitis. Recent studies on intestinal microbiota have revealed that microorganisms forming a biofilm play important roles in maintaining tissue homeostasis through their own metabolism. However, the physiological roles of oral microorganisms such as S. mutans are still unclear. In our current study, we identified that constituents released from S. mutans (CR) reduce arecoline-mediated cytotoxicity without producing toxic effects themselves. Arecoline, as a major alkaloid of areca nut, is known to mediate cytotoxicity on oral epithelial cells and induces a sustained intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) increase that is cytotoxic. The exposure of human gingival fibroblast (HGF) cells to CR not only inhibited the sustained $[Ca^{2+}]_i$ increase but also the initial $[Ca^{2+}]_i$ elevation. In contrast, CR had no effects on the gene regulation mediated by arecoline. These results demonstrate that S. mutans has physiological role in reducing cytotoxicity in HGF cells and may be considered a novel pharmaceutical candidate.

Discrimination of Bolt and Nut's Presence in a T-Bar Using Image Processing Method (영상처리 방법을 이용한 T-Bar의 볼트와 너트 유무 판별)

  • Joo, Ki-See;Kim, Eun-Seok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.5
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    • pp.937-943
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    • 2009
  • In this paper, the algorithm discriminating the existence and nonexistence of bolts and nuts using image processing in an automobile T-Bar influencing the vibration of a frame, is introduced. To distinct whether bolts and nuts exist or not, the features of bolts and nuts are learned, and then these feature values are matched using a statistical pattern matching algorithm. Furthermore, the minimum and maximum variation rate of pixel values are used since the matching rate is low with the large variation of pixel values of bolts and nuts in each image. The proposed method in this paper is very efficient in the automation of inspection requiring real time since the inspection time is significantly reduced compared with the conventional methods.