• 한국식품영양과학회지
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• 제29권1호
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• pp.76-79
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• 2000

The effects of packaging conditions on freshness extension of squash (Cucurbita moscata) were investigated during 7-day storage at 2$0^{\circ}C$. Weight loss of squash packed with corrugated paperboard box (control) was 5.5%, and those of LDPE (low density polyethylene, Ф0.02 mm), LDPE (Ф0.04mm) film and EPS (expanded polystyrene) box were 0.9%, 0.8%, and 1.1%, respectively. Firmness of EPS was 11% higher than that of control, chlorophill content of squash packed with EPS box was 18.9% higher, and total ascorbic acid content of squash packed with EPS box was 29.4% higher than that of control. Quality of packed squash was not different between EPS packages and LDPE packages. Decay of control was 1~2 pieces per box, but was not found in the LDPE, EPS box. Preferences in overall appearences of LDPE, EPS box was better than those of control.

• 한국안전학회지
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• 제16권4호
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• pp.153-159
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• 2001

Recently, the underground reinforced concrete(RC) box structures have been increasingly built in Korea. In such structures, the heat of hydration may cause serious cracking problems. The RC box structures are classified in this category that needs much attention to control the hydration heat during construction, which causes the restraining effects on the boundaries. The purpose of the present study is to develop the rational construction method to control the thermal cracking problem of the box structures. In this study, the causes and mechanism of thermal cracking according to construction stages in the RC box structures are thoroughly analyzed. The major influencing variables are studied through the finite element analysis which affect the thermal cracking of RC box structures. The research results of the present study can be efficiently used for the control of cracking of box structures during construction stages.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1337-1342
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• 1990

This paper deals with control system design strategy for electrolmaginetic suspension (E.M.S.) system. For a successful control of E.M.S. system, the nature of E.M.S. system is deeply studied in the view point of non-linear, open-loop unstable, time-varying, non-minimum phase system. To find a special control treatment for E.M.S. system, analyses and simulations for various models are carried out. As one of the successful candidates, adaptive control concept is introduced and sample hardware system using digital signal processor is implemented.

• Corrosion Science and Technology
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• 제10권3호
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• pp.87-94
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• 2011

The typical corrosion prevention method inside the steel upper box girder in a suspension bridge involves the use of paints. However, in an effort to reduce environmental impact and cost, the suspension portion of the Yeongjong Bridge, Korea utilizes dehumidification systems to control humidity and prevent corrosion inside its box girder. Maintaining a uniform humidity distribution at the proper level inside the box girder is critical to the successful corrosion control. In this study, the humidity and the resultant atmospheric corrosivity inside the box girder of the Yeongjong Bridge was monitored. The corrosion rate of the steel inside the box girder was obtained using thin-film electrical resistance (TFER) corrosion sensors. Time-of-wetness (TOW) measurements and the deposition rates of atmospheric pollutants such as $Cl^{-}$ and $SO_{x}$ were also obtained. Classification of the atmospheric corrosivity inside the box girder was evaluated according to ISO 9223. As a result, no corrosion was found in the upper box girder, indicating that the dehumidification system used in the Yeongjong Bridge is an effective corrosion control method.

• 한국포장학회지
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• 제8권2호
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• pp.27-31
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• 2002

제주산 감귤을 기존의 골판지와 이골판지에 특성이 다른 선도 유지기능성 소재 3종을 상자 내면에 코팅하여 여기에 감귤을 넣고 $25^{\circ}C$에 8일간 저장하면서 선도 유지효과를 조사하였다. 중량은 모든 포장구에서 2.6-3.7%가 감소하였고 산도와 당도는 포장구간에 차가 없었으며 비타민 C 함량은 대조구 보다 R-Box와 Y-Box가 10% 높게 유지되고 있었다. 부패율도 R-Box는 4%였으나 나머지 포장구는 8-11%의 감귤이 부패되었으며 외관도 R-Box가 가장 양호하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.435-439
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• 1998

A control strategy for flexible structure under irregular disturbance by using of$\boxDr$random gain$\boxUl$is developed and implemented. System equation is transformed to stochastic domain by F-P-K approach from physical domain. A controller is designed in the stochastic domain, accordingly system is controlled by$\boxDr$random gain$\boxUl$in time domain. In the paper, a new control technique is successfully employed for flexible system under white noise, and the result is verified by Monte-Carlo simulation and compared with the performance via LQR controller.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.49-53
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• 1994

Advanced Real-Time Satellite Simulator(ARTSS) has been developed to support the telemetry, tracking and command operations of the ETRI satellite control system and to provide satellite engineers a more powerful and informative satellite simulations tool on the desktop. To provide extensive simulation functions for a communication satellite system in the pre-operational and operational missions, ARTSS uses a geosynchronous orbit(GEO) satellite model consisting of the attitude and orbit control subsystem, the power subsystem, the thermal subsystem, the telemetry, command and ranging subsystem, and the communications payload subsystem. In this paper, the system features and functions are presented and the satellite subsystem models are explained in detail.

• 한국포장학회지
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• 제4권2호
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• pp.18-23
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• 1998

개발한 EPS 포장상자가 오이의 신선도 유지효과 기능이 있는지의 여부를 분석코자 오이를 골판지상자와 0.02와 0.04mm 두께의 LDPE필름으로 포장 $20^{\circ}C$에 저장하면서 신선도 유지효과를 비교하였다. 저장 7일후 중량감소는 대조구는 4.9%, EPS 상자는 0.8%의 중량감소가 나타났고, 경도는 대조구 보다 필름구와 EPS 포장구에서 높았으며 비타민C도 EPS 포장구가 대조구 보다 15% 높게 유지되고 있었고 클로로필 함량은 EPS 포장구가 대조구 보다 21% 높게 유지되고 있었다. 부패는 포장구간에 나타나지 않았으며 대조구에서 표면이 노랗게 변하였으나 필름구와 EPS에서는 변하지 않았다 EPS 포장상자는 신선도 유지효과가 기존의 골판지상자 보다 더 우수하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.185-190
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• 1993

The POSTECH Hand adopting coupled tendon driven technique with planar two fingers is developed. The hand is designed to emulate principal motions of the human hand which has two and three joints respectively. Its kinematic parameters are determined through a parameter optimizing technique to aim at improving the isotropy of fingertip motions with new criterion functions of design. For the control of the hand, tension and torque control algorithms are developed. Based on the virtual stiffness concept, we develop the stiffness control method of a grasped object with redundant finger mechnism and investigate experimentally.

• 한국식품저장유통학회지
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• 제5권4호
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• pp.331-334
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• 1998

기능성 MA필름을 생산하여 이를 골판지 상자의 내부에 첨합시킨 FC상자의 활용가능성을 조사하고자 골판지 상자와 기능성 MA필름대를 골판지 상자 내부에 첨합시킨 FC포장구와 LDPE 및 기능성필름과 대조구로 골판지 상자만으로 포도를 포장하여 25 C에 저장하여 품질변화를 조사한 결과, FC 상자와 LDPE와 CE포장구는 대조구 보다는 중량감소율이 현저히 낮았으며 비타민C의 함량도 33% 높게 유지되고 있었다. 산도와 환원당 함량은 포장구들간에는 큰차이가 없었다. 외관 및 부패를 조사한 결과 대조구에 비해 개발포장구에서 품질이 더 높게 유지되고 있어 FC 포장재를 포도 포장용 상자로 활용가능성이 확인되었다.