• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1219-1227
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• 2000

Rumination behavior, in vivo digestibility of cell wall constituents, particle size reduction in the rumen, and retention time in the digestive tract of sheep were examined using rice and oat straw as roughage sources. The in sacco digestibility, rumen fermentation, and microbial population and internal adenosine 5-triphosphate (ATP) content were also determined under feeding conditions of high-roughage and high-concentrate diets. Chewing number and time in rumination behavior were higher with rice straw than with oat straw, while the in sacco and in vivo DMD of rice straw were consistently lower than those of oat straw. Rice straw also showed higher frequency of thinner and longer particles in the rumen contents and lower retention time in the whole digestive tract as compared to those of oat straw. Rice straw was more effective to maintain the ruminal pH than oat straw, being reflected in higher internal ATP content of large-type protozoa on the high- concentrate diet. Changes in the ruminal microflora by shifting from the low- to the high- concentrate diet were also different between rice and oat straw.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 Proceeding
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• pp.141-148
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• 2003

Customer retention is a common concern for many industries and a critical issue for the survival in today's greatly compressed marketplace. Current customer retention models only focus on detection of potential defectors based on the likelihood of defection by using demographic and customer profile information. In this paper, we propose a dynamic procedure for defection detection and prevention using past and current customer behavior by utilizing SOM and Markov chain. The basic idea originates from the observation that a customer has a tendency to change his behavior (i.e. trim-out his usage volumes) before his eventual withdrawal. This gradual pulling out process offers the company the opportunity to detect the defection signals. With this approach, we have two significant benefits compared with existing defection detection studies. First, our procedure can predict when the potential defectors could withdraw and this feature helps to give marketing managers ample lead-time for preparing defection prevention plans. The second benefit is that our approach can provide a procedure for not only defection detection but also defection prevention, which could suggest the desirable behavior state for the next period so as to lower the likelihood of defection. We applied our dynamic procedure for defection detection and prevention to the online gaming industry. Our suggested procedure could predict potential defectors without deterioration of prediction accuracy compared to that of the MLP neural network and DT.

• Journal of Mechanical Science and Technology
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• 제18권6호
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• pp.990-1001
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• 2004

The retention of a molten pool vessel cooled by internal vessel reflooding and/or external vessel reactor cavity flooding has been considered as one of severe accident management strategies. The present numerical study investigates the effect of both internal and external vessel mixed cooling on an internally heated molten pool. The molten pool is confined in a hemispherical vessel with reference to the thermal behavior of the vessel wall. In this study, our numerical model used a scaled-down reactor vessel of a KSNP (Korea Standard Nuclear Power) reactor design of 1000 MWe (a Pressurized Water Reactor with a large and dry containment). Well-known temperature-dependent boiling heat transfer curves are applied to the internal and external vessel cooling boundaries. Radiative heat transfer has been considered in the case of dry internal vessel boundary condition. Computational results show that the external cooling vessel boundary conditions have better effectiveness than internal vessel cooling in the retention of the melt pool vessel failure.

• 수산해양기술연구
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• 제52권2호
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• pp.88-95
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• 2016

Most grid sorting has been used to sort out flatfish in shrimp fisheries, while double grid systems have been tested to separate smaller shrimp. The escape of juvenile red seabream through separating panels made with steel grids or large mesh tested for masking effects in a two-species system. Fish behavior was observed in a circulating water tank. The escape rate was 20% greater with the separating codends than with the normal codend in the single-species experiments. The rates in the two-species experiments were 30% or 20% greater than the single-species rates for the normal or separating codends, respectively. The seabream retention rates in the grid separator codend decreased as rockfish retention increased, possibly due to a threat effect. Conversely, the retention rate of both species increased concurrently in the net separator, possibly due to a masking effect. The escape rates of juvenile red seabream varied by compartment in the mesh separating codend. These results suggest that grid separating codends can be used in the field as towed fishing gear to reduce juvenile catch.

• 한국지반공학회논문집
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• 제39권11호
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• pp.53-62
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• 2023

동결토의 부동수분특성은 지반의 열-수리-역학적 거동 전반에 걸쳐 지배적인 영향을 미치며, 동결 지반의 안정성 평가를 위해서는 대상 지반재료의 부동수분특성에 대한 면밀한 검토가 필요하다. 본 연구에서는 간극수 염분농도를 고려한 동결 사질토의 부동수분곡선을 평가하기 위하여 흙의 어는점 및 부동수분을 측정하는 실내 실험을 수행하였으며, 계측된 실험데이터를 기반으로 부동수분포화도 곡선을 간편하게 추정할 수 있는 경험적 모델을 새롭게 제시하였다. 또한, 제안된 경험적 모델을 입력자료로 적용한 해석모델의 시뮬레이션 결과를 실험데이터와 비교함으로써 사용된 부동수분곡선의 적정성을 검증하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제3권3호
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• pp.132-138
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• 2003

We investigated the polarization retention characteristics of ferroelectric capacitors with $Pb(Zr,Ti)O_3$ (PZT) thin films which were fabricated by different deposition methods. In thermally-accelerated retention tests, PZT films which were prepared by a chemical solution deposition (CSD) method showed rapid decay of retained polarization charges as the thickness of the films decreased down to 100 nm, while the films which were grown by metal organic chemical vapor deposition (MOCVD) retained relatively large non-volatile charges at the corresponding thickness. We concluded that in the CSD-grown films, the thicker interfacial passive layer compared with the MOCVD-grown films had an unfavorable effect on retention behavior. We observed the existence of such interfacial layers by extrapolation of the total capacitance with thickness of the films and the capacitance of these layers was larger in MOCVD-grown films than in CSD-grown films. Due to incomplete compensation of surface polarization charges by the free charges in the metal electrodes, the interfacial field activated the space charges inside the interfacial layers and deposited them at the boundary between the ferroelectric layer and the interfacial layer. Such space charges built up an internal field inside the films, which interfered with domain wall motion, so that retention property at last became degraded. We observed less imprint which was a result of less internal field in MOCVD-grown films while large imprint was observed in CSD-grown films.

• 대한화학회지
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• 제39권11호
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• pp.848-855
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• 1995

평판형 열장흐름분획법에서 중력효과에 의한 polystyrene(PS)와 polymethylmethacrylate(PMMA)의 머무름 거동에 관하여 연구하였다. 하향 이동상 흐름의 경우 이동상 흐름 방향과 같은 방향으로 작용하는 중력 효과는 수평면 으로부터 장치각도가 0.deg.에서 60.deg.까지 변화함에 따라 증가하였다. 이 효과는 PS와 PMMA의 머무름 시간을 작게 하였고, 무차원 변수 .lambda.의 값을 증가시켰다. 그리고 분자량이 다른 두개의 고분자 머무름 시간차를 감소시켜 분리기능 저하시켰다. 상향 이동상 흐름의 경우 이동상 흐름의 반재 방향으로 작용하는 중력 효과는 수평면으로부터 장치의 각도가 0.deg.에서 60.deg.까지 증가함에 따라 증가하였다. 이 효과는 PS와 PMMA의 머무름 시간을 크게 하였고, 무차원 변수.lambda.의 값을 감소 시켰다. 그리고 분자량이 다른 두 개의 고분자 머무름 시간 차를 증가시켜 분리능을 향상시켰다.

• 한국의류학회지
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• 제23권1호
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• pp.90-110
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• 1999

Understanding consumer complaining behaviors plays a key role in post-purchase satisfaction customer retention and long-term customer relationships. This research was conducted to empirically investigate 1) the taxonomy of complaining behavior 2) causes and types of clothing complaining behavior according to sex. The subjects compoed of 250 male and 358 female consuemrs. Data were colleted through questionnaires employing the critical incident methodology. The findings indicated that clothing complaining behavior was fitted well into Singh(1998)'s three-factor model(i. e. voice/private / third-party complaining behaviors) these factors explained 53% of the total variances 75.1% of male and 65.2% of female group complained of poor instruental performance. The types of complaining behaviors were no action negative word-of-mouth to friends and associates n order. Most dissatisfied consumers didn't assert positive consumer's right. Marketer should increase the accessibility of their complaint receiving mechanisms to passive customers.

• 분석과학
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• 제6권5호
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• pp.453-462
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• 1993

본 연구는 열장 흐름 분획법을 이용하여 혼합 용매에서의 폴리스티렌의 머무름을 측정하고 용매의 조성이 시료의 머무름거동에 미치는 영향을 조사하였다. 시료는 분자량이 35,000, 110,000, 200,000, 470,000인 폴리스티렌을, 이동상은 테드라히드로퓨란(THF), 클로로포름(CHL), 시클로헥산(CH), 그리고 벤젠(BZ)의 단일용매 및 혼합용매를 사용하였다. 시료의 분자량과 혼합용매의 조성의 변화에 따라서 시료의 머무름비와 열확산계수를 측정하였으며, 그 값들을 시료와 용매의 물리화학적인 성질과 연관시켜 설명하였다. 즉, 시료의 머무름비는 이동상의 밀도의 영향을 크게 받으며 이동상의 밀도가 클수록 머무름비가 증가함을 알 수 있었다. 또한 이동상에 포함된 poor 용매의 함량이 증가할수록 열확산계수는 감소하였다.

• 한국물환경학회지
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• 제21권1호
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• pp.52-58
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• 2005

The assessment on characteristics of hydraulic behavior and water quality variations of underground reservoirs of buildings were studied. Firstly, it was thought that underground reservoir capacities($m^3$) of buildings should be not determinated by the uniform and same methods but be estimated on the basis of the dwelling areas on dominated households and their residential characteristics, because these characteristics influence significantly on actual water usages and patterns of buildings. Secondly, it was likely that the average reduction rate of residual chlorine in underground reservoirs were affected from the their capacities, because the average reduction rate of residual chlorine in underground reservoirs under $1,000m^3$ was 43 percent, on the other hand, that rate of underground reservoirs over $1,000m^3$ was 60 percent. Thirdly, through the field investigation, the retention time of drinking water in underground reservoirs were in the range from 0.3 day to 3.9 day. In addition to, the average reduction rate of residual chlorine were depended largely on the retention time of drinking water. When the retention time was under 24 hours, the average reduction rate of residual chlorine was 45 percent, and in case of over 24 hours, was 49 percent. Fourth, water level in underground reservoirs was averagely varied in the range from 0.1 m to 2.65 m at the height of underground reservoirs. If considered actual height of underground reservoirs, 37.6 percent of the height of underground reservoirs was only used. Consequently, the frequency of the inflow and outflow of drinking water in underground reservoir were very increased, and had an effect on the reduction of residual chlorine. Lastly, the investigations on hydraulic structure characteristics of underground reservoirs inside showed the locations of inflow and outflow of drinking water almost were in the opposite direction. And some buildings had several baffles in the middle. Nevertheless, their installations had no beneficial for the improvement of water quality.