• Tunnel and Underground Space
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• v.27 no.6
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• pp.351-356
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• 2017

This study introduces the current status of the design for safety(DfS) introduced as one of the owner - centered construction site safety management plan, and presents the problems and the improvement plan. The design for safety has been shifting from the construction management-oriented safety management to the owner-centered safety management system, The owner has to make the design considering the safety from the design stage centered on the owner. The owner has to review and approve the adequacy of the safety-conscious design and The risk factors that can not be eliminated during design are the system to prevent the disaster at the construction site by planning to eliminate the risk factor when writing the safety management plan that is made at the construction stage. The design for safety system implemented from May 2016 will be further developed to prevent the risk of safety accidents that may occur in construction sites, contributing greatly to the reduction of construction accident. In addition, it suggests ways to develop more efficient and convenient system through continuous hazard finding and system improvement.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.419-425
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• 2011

Changes in the flavor of muskmelons stored at different temperatures were examined to judge aroma patterns during storage. A mass-spectrometry based electric nose was used to distinguish the subtle differences in the muskmelon's volatile compounds. The data were used for a discriminant function analysis (DFA), and then the partial least square algorithm was used for a quantitative analysis. Volatile components in the muskmelons increased with storage, and the first discriminant function score (DF1: $r^2$=99.88%, F=3072.5) moved from a positive position to a negative position as the storage period increased. The proper point of maturity was anticipated as the $28^{th}$ day at 0$^{\circ}C$, $21^{st}C$ day at 4 and 7$^{\circ}C$, and $14^{th}$ day at 10$^{\circ}C$. Also, using the DF1 score we could predict the general tendency (vitamin C, stem moisture, acidity) of the muskmelons. The electronic nose revealed that the major volatile compounds that changed during storage of the melons were ethyl ethyl acetate, butyl acetate, nonanol, dodecanoic acid, hexadecanoic acid and tricosane. The amount of volatile compounds detected increased during storage.

• Nuclear Engineering and Technology
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• v.13 no.1
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• pp.12-21
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• 1981

An extension work of the previous paper on the rewetting velocity model is presented. Application of the rewetting velocity model presented elsewhere requires a priori values of ø. In the absence of ø values, film boiling heat transfer coefficient ( $h_{df}$ ) and fog-film length (ι) data are needed. To provide these informations, a modified Bromley's correlation is first derived and used to obtain $h_{df}$ values at higher pressure conditions. In addition, the analysis of the precooling parameters, such as ø and ι is further extended using much more expansive PWR FLECHT data. Thus, the applicable range of the rewetting velocity model is further expanded in this work.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.358-366
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• 2023

Due to the International Maritime Organization's (IMO) environmental regulations on NOx and SOx, LNG-fueled eco-friendly ships are gaining attention worldwide, and various eco-friendly ships are being proposed and demanded for conversion to eco-friendly ships in Korea, as the eco-friendly ship law has recently been enforced. In this study, the initial basic design was performed to convert an existing Marine Gas Oil (MGO) fueled ship into an LNG-DF propulsion ship, targeting medium-sized ship, to select the fuel tank capacity and main dimensions and appropriate fuel ratio between the two fuels. In particular, Sustainable basic design method considering environmental impact were proposed by performing a Life Cycle Assessment (LCA) throughout the design process, and various design options were compared and analyzed to meet different design conditions by applying them.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.5
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• pp.551-559
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• 2008

An experimental study was carried out to evaluate the potential of flotation process for the secondary clarifier of an activated sludge process. Flotation techniques, applied in this study, include electrofloation (EF) which generated fine bubbles smaller than $35{\mu}m$ in average and diffuser flotation (DF) which generated fine bubbles smaller than $55{\mu}m$ in average. The batch experiments were done with activated sludge displaying various characteristics. It was shown that the efficiency of solids/liquid separation was reduced as the diluted sludge volume index ($DSVI_{30}$) of activated sludge increased. The dependency, however, gradually decreased as the gas to solids (G/S) ratio increased. Thickening efficiency of EF was more than 2~10 times and DF process was more than 1.5~5 times as compared with gravity sedimentation (GS). Stable sludge blanket was maintained regardless of sludge settleability when the G/S ratio was 0.019 in the EF. On the other hand, Serious deterioration in the sludge blanket was observed in the DF depends on G/S ratio and sludge settleability. And For EF and DF, the suspended solids concentration of effluent was not nearly influenced on settleability of activated sludge and more clear than GS. A biological nutrient removal (BNR) process, combined with EF as a secondary clarifier was operated for three months. The mean MLSS (mixed liquid suspended solids) concentration in the reactor and mean solids concentration of return sludge were estimated to be 5,340 mg/L and 16,770 mg/L, respectively. The water quality of effluent was considerably stable and low value was accomplished, that was, standard suspended solids concentration $0.07{\pm}0.51mg/L$ and standard turbidity $1.44{\pm}0.56NTU$. The EF could be applicable for enhancement of efficiency of activated sludge system as well as improvement of the water quality of effluent.

• Journal of Trauma and Injury
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• v.28 no.3
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• pp.158-169
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• 2015

Purpose: Frostbite can affect still soldiers. Initial clinical manifestations are similar for superficial and deep frostbite, so early treatment is identical. It is under-estimated by physicians. We try to identify the challenges of managing these complex tissue injuries. Methods: A retrospective analysis of 84 patients hospitalized at AFCH from 2009 to 2015 was conducted. We investigated differences of epidemiological characteristics, identification of soft tissue injury, treatment and complications between superficial (SF: 43; 51.2%) and deep (DF: 41; 48.8%) frostbite. Results: The major (94.0%) developed frostbite in dry circumstances (89.3%). Wet circumstances (66.7%) were more susceptible to DF rather than dry (46.7%). The 38 (45.2%) arrived to specialist within 7days. Most prone sites were feet, followed by hands. Toes had more deep injuries. DF presented more increased levels of ALT, CPK, CKMB, CRP. The bone scan of W+S+ was 48.3%, 87.1% and W+S- was 20.7%, 12.9%, respectively. The treatment resulted in improved or normalized perfusion scan with matching clinical improvement. It was a good tool to assess treatment response. Eighteen normal and 8 stenotic type of PCR resulted in normal with matching clinical improvement. One continuous obstructive waveform led to minor amputation. Twelve underwent both PCR and MRA. Among 6 normal PCR, 5 showed normal and one stenosis in MRA. All 5 stenosis and one obstruction showed the same findings in MRA. It was a good tool to evaluate vascular compromise. They were treated with rapid rewarming (11.6%, 22.0%), hydrotherapy (16.3%, 29.3%), respectively. Six (14.6%) underwent STSG, 2 (4.9%) had digital amputation in DF. Berasil, Ibuprofen, Trental were commonly administered. PGE1 was administered selectively for 6.8, 10.8 days, respectively. Raynaud's syndrome (16.3%), CRPS (4.7%), LOM (14.6%) and toe deformity (4.9%) were specific sequelae. Conclusion: We should recommend intensive foot care education, early rewarming and evacuation to specialized units. The bone scanning and PCR should allow for a more aggressive and active approach to the management of tissue viability.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.141-144
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• 2000

PRML (partial response maximum-likelihood) 과 FDTS/DF (fixed-delay tree search with decision feedback)는 기록 저장 시스템에서 준최적의 성능을 보임이 잘 알려져 있다. 그러나, 위와 같은 정보열 검출 기법은 피할 수 없는 복잡도 문제를 가지고 있다. 본 논문은 최소 run 길이 제한조건 d=2를 가진 광기록 채널을 위한 다양한 저복잡도 검출 기법을 다룬다. 우선, 결정 궤환 기법을 이용한 이산 정합 여파기 (discrete matched filter with decision feedback：DMF/DF)가 기존의 PRML로부터 유도된다. 유도된 시스템은 PRML보다 결정 궤환에 의한 성능 이득을 갖는다. 또한, 메트릭 계산을 사용하지 않는 저복잡도 FDTS/DF가 유도된다. 모의실험 결과에 의하면, 유도된 저복잡도 검출 기법들은 기록 밀도 S>=5.5에서 P(D)=1+D+D/sup 2/+D/sup 3/의 target을 갖는 PRML보다 우수한 성능을 보인다.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.3-4
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• 2001

Normal cells proliferate generally a limited number doublings in culture and only rarely have they been shown to overcome cellular senescence and crisis stages, and immortalize spontaneously. I have established a number of non-chemically and non-chemically immortalized embryo fibroblastic (EF) cell lines in continuous cell culture. These include the spontaneously immortalized cell line, DF-1 and several immortal EF cell lines derived from various embryonic tissues. I have previously demonstrated that all of the immortal EF cells established have rapid cell proliferation capacity compared to primary EF cells, presumably due to the deregulation of cell cycle regulators such as p53, E2F-1 and the numerous cyclins. DF-1 cells, in particular, were shown to proliferate more rapidly under normal culture conditions compared to other immortal EF cells, implicating other mechanisms may be important for regulating their growth. The possible mechanism(s) underlying the accelerated growth of DF-1 cells will be addressed in this study. (omitted)

• Journal of Applied and Pure Mathematics
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• v.4 no.1_2
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• pp.51-61
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• 2022

Let G be a graph. Let f : V (G) → {0, 1, 2, …, k-1} be a map where k ∈ ℕ and k > 1. For each edge uv, assign the label |f(u) - f(v)|. f is called k-total difference cordial labeling of G if |t_df (i) - t_df (j) | ≤ 1, i, j ∈ {0, 1, 2, …, k - 1} where t_df (x) denotes the total number of vertices and the edges labeled with x. A graph with admits a k-total difference cordial labeling is called k-total difference cordial graphs. In this paper we investigate the 4-total difference cordial labeling behaviour of shell butterfly graph, Lilly graph, Shackle graphs etc..

• 대한핵의학회:학술대회논문집
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• 1971.11a
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• pp.87.1-87.1
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• 1971