• 제목/요약/키워드: EPS

검색결과 904건 처리시간 0.026초

장기유통을 위한 포장방법이 포도 품질변화에 미치는 영향 (Effects of Packing Materials on the Quality of Grape for Long-Term Market Circulation)

  • 남상영;김경미;강한철;황종택;김태수
    • 한국식품저장유통학회지
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    • 제5권4호
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    • pp.315-319
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    • 1998
  • 유통을 위한 포도 보존 중 품질에 미치는 영향을 구명하여 보존기간 연장에 효과적인 적정 포장재 제작에 대한 기초자료를 얻고자 포도 캠벨얼리를 공시하여 스치로폴 상자, 마닐라상자 등 6처리를 두어 시험한 결과, 중량감소는 유통일수가 경과함에 따라 많았으며, 처리 간에는 15일 보존시 스치로폴상자에 비해 스치로폴상자+(스치로폴접시 + BioPE 필름밀봉), 스티로폴상자 + (스치로폴접시 + 랩 밀봉)처리가 적었으며, 비정상과는 밀봉구에서 많았으나, 축과는 밀봉으로 인한 수분증발 억제로 인하여 오히려 감소하였다. 외관상 품질 및 식미는 보존기간이 경과할수록 저하되었으나, 5일 보존 시에는 바이오상자 처리 포도의 품질이 우수하였고, 경도는 스티로폴상자 + (스치로폴접시 + 바이오필름) 처리에서 감소 폭이 가장 적었으며, 성분변화는 보존기간 경과에 따른 일정한 경향이 없었으며, 밀봉처리에서 당도의 감소 폭이 컷다.

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로봇 조향 기반 EPS HILS 시스템의 개발 및 검증 (Development and Validation of Robot Steered EPS HILS System)

  • 홍태욱;권재준;박기홍;기시우;최상수
    • 한국정밀공학회지
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    • 제30권1호
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    • pp.85-95
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    • 2013
  • As the conventional hydraulic power steering system in the passenger vehicles is being rapidly replaced by EPS (Electric Power Steering) system, performance evaluation of the EPS system has become an important issue in the automotive industries. But the evaluation process takes significant expertise since steering conditions in the test protocols must be implemented with high accuracy. EPS HILS (Hardware-In the-Loop Simulation) system is developed together with robot steering system in this study. Main components of EPS HILS system include: C-EPS hardware, CarSim vehicle model, and road reaction force generation system powered by servo motor. The robot steering system, operated by another servo motor, was combined with EPS HILS system to substitute for steering efforts of human driver. The road reaction force generation system and the robot steering system were carefully validated by using the data obtained from vehicle tests. An on-center handling test was conducted by using EPS HILS system combined with the robot steering system. In the result of this study, robot-steered EPS HILS system developed with its high reliability and no need of skilled driver's, can be widely adopted to evaluate any performance of EPS system.

연성포장의 노반재료로서 EPS 지오폼의 회복탄성계수에 관한 적합성 연구 (A Feasibility Study on Resilient Modulus of Expanded Polystyrene (EPS) Geofoam as a Flexible Pavement Subgrade Material)

  • 박기철;장용채
    • 한국지반환경공학회 논문집
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    • 제12권12호
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    • pp.63-70
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    • 2011
  • EPS지오폼은 다양한 강도, 밀도, 그리고 크기로 생산되는 일종의 화학합성물이다. EPS지오폼에 관한 근래의 발전으로 인해서, 그것의 사용은 급격하게 늘어나고있다. 이것은 초경량 재료로서 단위중량이 약 $0.16{\sim}0.47kN/m^3$ 인데, 이것은 채움재의 용도로 가장 대표적인 흙의 단위중량 $6.3{\sim}15.7kN/m^3$와 동일한 내구성을 가진다. 이런 장점에도 불구하고, EPS지오폼에 대한 회복탄성계수 표준측정방법은 보고된 바가 없는 실정이다. 본 연구의 주된 목적은 연성포장의 노반에 적용될 때의 EPS회복탄성계수의 적합성을 연구하는 것이다. 적합성연구는 삼축압축시험의 결과를 토대로 이루어졌으며, 연성포장의 노반재료로써 EPS는 실험결과의 분석과 근본적인 회복탄성의 특성을 비교분석하여 그것의 적합성을 확인해 보았다.

EPS로 뒷채움된 지반의 장기거동특성 (Long-term Behavior Characteristics of Backfilled Ground by EPS)

  • 천병식;정창희;최희림
    • 한국지반공학회논문집
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    • 제23권10호
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    • pp.151-161
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    • 2007
  • EPS는 자립안정성이 우수한 특성으로 인하여 세계적으로 건설현장에 널리 쓰이고 있다. EPS 공법은 일반적인 시공초기에 관하여 주로 연구되어 있고, EPS 재료의 내구성 및 적용지반의 장기거동에 관한 연구는 부족한 실정이다. 본 연구에서는EPS가 적용된 교대배면 뒷채움 지반의 장기 거동특성을 파악하기 위하여 EPS재료의 내구성 및 크리프 특성 분석, 시추조사, 현장 및 실내시험을 수행하였으며, 각종 시험결과 및 시공시 측정한 지반거동 계측자료를 고려한 유한요소해석을 통하여 장기 지반거동 특성을 파악한 결과, EPS 공법의 하중경감 효과에 의한 침하량 감소, 교대에 작용하는 응력감소 효과 및 측방유동 방지대책으로 우수한 적용성을 확인할 수 있었다.

Flexural Behavior of Polymer Mortar Permanent Forms Using Methyl Methacrylate Solution of Waste Expanded Polystyrene

  • Bhutta, M. Aamer Rafique;Tsuruta, Ken;Ohama, Yoshihiko
    • International Journal of Concrete Structures and Materials
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    • 제2권1호
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    • pp.35-39
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    • 2008
  • This experimental study examines the applicability of polymer mortar permanent forms using a methyl methacrylate (MMA) solution of waste expanded polystyrene (EPS) to develop effective recycling processes for the EPS, referring to the flexural behavior of a polymer-impregnated mortar permanent form with almost the same performance as commercial products. An MMA solution of EPS is prepared by dissolving EPS in MMA, and unreinforced and steel fiber-reinforced polymer mortars are mixed using the EPS-MMA-based solution as a liquid resin or binder. Polymer mortar permanent forms (PMPFs) using the EPS-MMA-based polymer mortars without and with steel fiber and crimped wire cloth reinforcements and steel fiber-reinforced polymer-impregnated mortar permanent form (PIMPF) are prepared on trial, and tested for flexural behavior under four-point (third-point) loading. The EPS-MMAbased PMPFs are more ductile than the PIMPF, and have a high load-bearing capacity. Consequently, they can replace PIMPF in practical applications.

EPS 제어시스템 장착 승용차의 통합적 시뮬레이션 기법 연구 (Simulation Integration Technique of a Full Vehicle Equipped with EPS Control System)

  • 장봉춘;소상균
    • 한국정밀공학회지
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    • 제23권6호
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    • pp.72-80
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    • 2006
  • Electric Power Steering (EPS) mechanism has become widely equipped in passenger vehicle due to the increasing environmental concerns and higher fuel efficiency. This paper describes the development of concurrent simulation technique and simulation integration technique of EPS control system with a dynamic vehicle system. A full vehicle model interacting with EPS control algorithm was concurrently simulated on a single bump road condition. The dynamic responses of vehicle chassis and steering system resulting from road surface impact were evaluated and compared with proving ground experimental data. The comparisons show reasonable agreement on tie-rod load, rack displacement, steering wheel torque and tire center acceleration. This concurrent simulation capability was employed fur EPS performance evaluation and calibration as well as for vehicle handling performance integration and synthesis.

다중양각스탬프를 사용하는 UV 나노임프린트 리소그래피공정에서 웨이퍼 미소변형의 영향 (The effect of micro/nano-scale wafer deformation on UV-nanoimprint lithography using an elementwise patterned stamp)

  • 정준호;심영석;최대근;김기돈;신영재;이응숙;손현기;방영매;이상찬
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.1119-1122
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    • 2004
  • In the UV-NIL process using an elementwise patterned stamp (EPS), which includes channels formed to separate each element with patterns, low-viscosity resin droplets with a nano-liter volume are dispensed on all elements of the EPS. Following pressing of the EPS, the EPS is illuminated with UV light to cure the resin; and then the EPS is separated from several thin patterned elements on a wafer. Experiments on UV-NIL were performed on an EVG620-NIL. 50 - 70 nm features of the EPS were successfully transferred to 4 in. wafers. Especially, the wafer deformation during imprint was analyzed using the finite element method (FEM) in order to study the effect of the wafer deformation on the UV-NIL using EPS.

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Enterobacter sp.의 다당 생산에 미치는 통기·교반의 단계적 증가 효과 (Stepwise Increasing Effects of Agitation and Aeration on Exopolysaccharide Production by Enterobacter sp.)

  • 이신영;이주하
    • 산업기술연구
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    • 제24권B호
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    • pp.171-176
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    • 2004
  • The effects of agitation and aeration for exopolysaccharide(EPS) production through batch cultivation of an Enterobacter sp. isolated from the composter were investigated. During the EPS fermentation under conditions of constant agitation speed from 200 to 900 rpm and constant aeration rate of 0.5-2.5 vvm, the low yields of EPS(4.8-5.2g/L) was observed as the viscosity increase of culture broth. With the stepwise increases in agitation speed and aeration rate, the EPS production and the viscosity of EPS were increased 1.3~1.4 times and 2.3~3.6 times higher than those of the fixed conditions, respectively. Therefore, these stepwise increases were considered as the key operating parameters for enhancing EPS production. The max. EPS(6.8g/L) and viscosity(14,000cp) were obtained when the agitation speed was increased from 300 to 900 rpm for 54hrs at 1.5 vvm.

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Prototype의 새로운 Electric Power Steering (EPS) System의 개발 (Development of a Prototype New Electric Power Steering (EPS) System)

  • 송정훈
    • 대한기계학회논문집A
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    • 제30권6호
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    • pp.684-690
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    • 2006
  • This study proposes and validates a new column type electric power steering system (EPS-TT). It is driven by a uni-directional motor and two electro-magnetic clutches. The assist motor produces assist torque in only one direction and two clutches transmit the torque to the column of steering system in either left or right direction with respect to the steering input. A full order and a reduced order models are developed to evaluate the EPS-TT. Models are also used to investigate the vehicle responses. A PID control logic is designed to control the torque of the assist motor. A driver model is applied to the system and the resulting performances are analyzed. The results show that the performances of the full order model are similar to those of reduced order model. The results also prove that the performances achieved by the EPS-TT are improved compared to those of a conventional EPS-TT across the frequency domain.

EPS의 압축성을 이용한 콘크리트 옹벽 시스템 연구 (Retaining Wall System Using the Compressible Inclusion Function of EPS)

  • 김진만;김호비;조삼덕;주태성;최봉혁
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.411-418
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    • 2001
  • The last 30 years have been significant worldwide growth in the use of EPS as a lightweight fill material. This paper analyzes the compressible inclusion function of EPS which can results in reduction of static earth pressure by accomodating the movement of retained soil. A series of model tests was conducted to evaluate the reduction of static earth pressure using EPS inclusion and determine the optimum stiffness of EPS, Also, field test was conducted to evaluate the reduction of static earth pressure using EPS inclusion. Based on field test it is found that the magnitude of static earth pressure was reduced about 20% compared with theoretical active earth pressure.

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