• 대한설비공학회지:설비저널
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• 제15권2호
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• pp.169-181
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• 1986

A numerical analysis has been conducted on the dehumidification phenomena of rotary absorptive dehumidifier. Parameters that affect the dehumidification efficiency, such as regeneration temperature, humidity, rotor angular velocity, air flow rate and regeneration section angle are studied and optimum driving conditions are determined from the results, Furthermore three new types of dehumidification method are developed to improve the efficiency They are named MODE 2, 3 and 4, while the present one MODE 1. Cooling zone has been constructed between regeneration and process Bone in MODE 2 and as a result exit temperature of the process air decreases. MODE 3 an improvement of MODE 2, recirculates the cooling air into the regeneration zone and regeneration input as well as exit temperature decreases. In MODE 4, some of tee regeneration air is recirculated and it cuts down the regeneration input. Among them MODE 3, showed the best dehumidification efficiency.

• 대한전자공학회논문지SP
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• 제44권6호
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• pp.54-62
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• 2007

본 논문에서는 기존의 고속 인트라 4$\times$4 예측 모드 선택 알고리즘을 인트라 16$\times$16 예측에 적용하여 연산량을 감소시키고, 변환 계수의 일부분만을 사용하여 인트라 16$\times$16 예측 모드 선택을 고속으로 수행하는 방법을 제안한다. 제안하는 방법은 기준 블록과 예측 블록간의 차분에 4$\times$4 변환을 수행한 후 DC계수 하나와 주변의 AC계수 3개만을 사용하여 모드 선택을 수행한다. 이론적인 분석과 실험적 결과를 통해서 제안한 방법을 사용하여 인트라 16$\times$16 예측 모드 선택을 수행할 경우 부호화효율의 큰 감소 없이 필요한 연산량을 50%까지 줄일 수 있었다.

• 한국군사과학기술학회지
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• 제25권2호
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• pp.160-168
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• 2022

The new IFF mode, Mode-5 replacing Mode-4, has already been established by the US DoD for its allies and NATO forces. A IFF retrofit program for replacing the Mark XII Mode-4 with Mark XIIA Mode-5 is in progress in order to overcome the security limitations of the former in R.O.K. IFF certification test for the new mode, Mode-5, has been performed on medium range surface to air missile platform of the Korean armed forces for the first time in R.O.K and this is regarded as a monumental event in Korean defense industry. The present paper is a discussion on the procedures applied to the IFF system retrofit and integration, lessons learned from AIMS test with the US AIMS PO as observer. The minimum modification from the existing Mark XII Mode-4 to Mark XIIA Mode-5 and evolutional adaption from previous design including interoperability are required for the system retrofit. Letter of Certification was received from the US AIMS PO after the tests. The authors propose that the lessons learned and know-how acquired during the tests are managed by the R.O.K Government as the standard structure of a database. It is expected that the use of the database will reduce the developmental difficulties and risk, also increase efficiency in future developments and other projects.

• 정보통신설비학회논문지
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• 제10권4호
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• pp.135-142
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• 2011

This paper proposes a performance evaluation method for power consumption of set-top box (STB) stand-by mode transition schemes. A stand-by mode transition scheme characterizes the timing of mode transition. The timing of mode transition affects the duration of stand-by mode operation, and the power consumptions of STB as well. Recently a fast stand-by mode transition scheme (FMT) has been proposed based on user input for selecting the device to be connected to TV. In this paper, we evaluate power consumption of FMT and a conventional mode transition scheme. For the computation of the duration of stand-by mode operation, the user input events are modeled as Poisson process. Simulation results based on the modeling reveals that the proposed scheme is more effective in power saving than the conventional scheme by up to 30%.

• 약학회지
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• 제43권6호
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• pp.776-781
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• 1999

Dockings of 4,5-diarylpyrroles into cyclooxygenase-1 and cyclooxygenase-2 were carried out by GOLD program. The sulfonyl groups bonded to 5-phenyl ring of 4,5-diarylpyrroles are directed to Arg513 of COX-2 and Tyr385 of COX-2 docking modes of pyrroles are different from COX-1. Tyr385 and Arg120 of COX-1 and COX-2 have been recognized as important residues. Val523 of COX-2 may be also important. A new COX-2 selective inhibitors could be designed from the docking study.

• 한국방사선학회논문지
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• 제15권4호
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• pp.437-444
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• 2021

두경부 CT 검사시 팬텀을 이용하여 Helical mode, High Pitch Mode, Volume Axial Mode 사용하여 획득한 CT 영상으로부터 환자의 피폭선량과 각 영상의 화질을 비교 및 분석하여 Volume Axial Mode의 유용성을 평가해보고자 한다. 두경부 CT 검사 시 각 mode에 따른 70 kVp, 80 kVp, 100 kVp 관전압에 따라 검사를 시행하였다. 사용 장비로는 GE사의 Revolution(GE Healthcare, Wisconsin USA) 모델과 iMED X-ray Phantom을 이용하였다. 검사 Mode에따른 kVp별로 얻어진 영상을 이용하여 팬텀의 피폭선량을 비교하였으며, 각 영상에 ROI를 설정해 신호대 잡음비와 대조도대 잡음비를 산출하여 영상의 화질을 비교하였다. Volume Axial Mode를 사용하여 검사하였을 때 팬텀의 피폭선량이 Helical에 비해 17.12% 낮게, High Pitch에 비해 5.35% 낮게 측정되었고, 신호대 잡음비와 대조도대 잡음비가 향상되었다. Volume Axial Mode는 고속 회전 스캐너를 이용하여 테이블의 이동이 없이 조사시간을 줄이고, High Pitch Mode와 Helical Mode를 사용했을 때 보다 팬텀의 0.28초의 단시간에 영상을 획득하여 피폭선량이 감소하고 영상의 화질 또한 향상되는 유용한 검사라 할 수 있다. 또, 몸이 불편한 환자의 촬영이나 긴급환자의 CT 촬영에 있어서 Volume Axial Mode의 빠른 검사시간은 최대의 장점이라고 볼 수 있다.

• 한국안전학회지
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• 제28권4호
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• pp.14-18
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• 2013

Blades of horizontal axis are nowadays made of composite materials. Generally, composite materials satisfy design provides lower weight and good stiffness, while laminate composites have often damages as like the delamination and cracks at the interface of laminates. The box spar and tail parts of a blade are composed of the CFRP/GFRP hybrid laminate composites. However, delamination and the interfacial crack often occur in the interface of CFRP/GFRP hybrid laminate composites under the mixed mode fracture condition, especially mode I and mode II. Therefore, there is a need for the evaluation of the mixed mode fracture behavior during the delamination of CFRP/GFRP hybrid laminates. This study shows the experimental results for the delamination fracture toughness in CFRP/GFRP hybrid laminate composites. Fracture toughness experiments and estimation are performed by using DMMB(Dissimilar mixed mode bending) specimen. The materials used in the test are a commercial woven type CFRP(Carbon fiber reinforced plastic) prepreg(CF3327) and UD type GFRP(Glass fiber reinforced plastic) prepreg(HD224A). A CFRP/GFRP hybrid laminate composite is composed by the 10 plies CFRP and GFRP prepreg for DMMB. A thickness of CFRP and GFRP layer is 2.5mm and 3.0mm, respectively. Also the fulcrum location which is a loading parameter is changed from 80 to 100mm on the specimen of length 120mm because it defines the ratio of mode I to mode II. In this study, the effects of the fulcrum location are evaluated in the viewpoint of energy release rate in mode I and mode II contribution. The results show that the delamination crack initiates at higher displacement and lower load according to the increase of the fulcrum location ratio. And the variation of the energy release rate for mode I and II contributions for the mode mixity are shown.

• 대한기계학회논문집A
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• 제20권4호
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• pp.1263-1274
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• 1996

In this paper, as elastic-plastic fracture toughness test under mixed mode loading was proposed using a single edge-cracked specimen subjected to bending moment(M), shearing force(F), and twisting moment(T). The J-integral of a crack in the specimen is expressed in the form J=$J_I$+ $J_II$$J_III$, where $J_I$, $J_II$ and $J_III$ are the components of mode I, mode II and mode III deformation, respectively. $J_I$, $J_II$ and $J_III$ can be estimated from M-$\theta$ ($\theta$;crack opening angle), F-U(U; crack shear displacement) and T-$\alpha$ ($\alpha$;crack twisting angle). In order to obtain the the M<-TEX>$\theta$, F-U and T-$\alpha$ diagram inreal time, a new deformaiton gage for mixed mode loading was proposed using the optical position sensing device(PSD). The elastic-plastic fracture toughness test was carried out with an aluminum alloy. The loading apparatus was designed and manufactured for this experiment. For the loading condition of the crack initatio in the mixed mode, the MMT -3(mode I+ mode II+ mode III) has the lowest values out of the all specimens. This implies that MMT-3 is possible of the crackinitation at lower load, if the specimen acts on together with the torque under the same loading condition. An elastic-plastic fracture toughness test using the PSD brings a successful experimentation in measuring the crack deformation(mode I+ mode II+ mode III).

• 한국안전학회지
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• 제31권5호
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• pp.7-15
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• 2016

The purpose of this paper is to carry out Failure Modes and Effects Analysis (FMEA) and use criticality in order to determine risk priority number of the components of electric power installations in Engineering college building of D university. In risk priority number, GROUP A had 7 failure modes; more specifically, Transfomer had 4 modes, Filter(C)(1 mode), LA(1 mode), and CB(MCCB)(1 mode), and thus 4 components had failure modes. In terms of criticality, high-grade group a total of 16 failure modes, and 7 components-LA(1 mode), CB(MCCB)(1 mode), MOF(2 modes), PT(1 mode), Transformer(7 modes), Cable(3 modes), and Filter(C)(1 mode)-had failure modes. Comparison of risk priority number and criticality was made. The components which had high risk priority number and high criticality were Transformer, Filter(C), LA, and CB(MCCB). The components which had high criticality were MOF and cable. In particular, Transformer(RPN: 4 modes, Criticality: 7 modes) was chosen as an intensive management component.

• Structural Engineering and Mechanics
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• 제2권4호
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• pp.345-357
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• 1994

The differential equations governing free, in-plane vibrations of linearly elastic circular arches with variable cross-sections are derived and solve numerically for quadratic arches with three types of rectangular cross sections. Frequencies, mode shapes, cross-sectional load distributions, and the effects of rotatory inertia on frequencies are reported. Experimental measurements of frequencies and their corresponding mode shapes agree closely with those predicted by theory. The numerical methods presented here for computing frequencies and mode shapes are efficient and reliable.