• 대한수의학회지
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• 제22권1호
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• pp.81-84
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• 1982

Renal dysfunction was experimentally induced with reductions in renal mass in dogs and then the remaining kidney function was estimated by blood urea nitrogen and serum creatinine concentrations. During experimental period, blood urea nitrogen and serum creatinine concentrations showed no variance in dogs with 50% reductions in renal mass, but these values were remarkably increased in dogs with 75% reductions in renal mass. It was considered that 75% reductions in renal mass was applicable as experimental models for renal dysfunction.

• 산학경영연구
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• 제20권1호
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• pp.123-143
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• 2007

이 연구는 조세특례제한법상 세액공제 및 세액감면 등의 직접감면과 준비금 손금산입 등의 간접감면의 세제혜택이 기업가치와 관련성이 있는지를 Ohlson(1995)모형을 토대로 1999년부터 2001년까지 3개년도 제조업을 대상으로 총 497개를 대상으로 실증분석하였다. 연구결과 주주지분 장부가치측면에서 직접 감면제도에 의한 기업합리화 적립금(누적액)과 당기전입 기업합리화적립금이 기업가치에 긍정적인 정(+)의 영향을 미치는 것으로 나타났다. 이는 세제지원의 성격과 사후관리제도의 정도 및 지속성의 차이로 인하여 기업가치 관련성에 있어서 서로 차이가 있을 수 있음을 보여주는 것이라 할 수 있다. 특히, 주주지분 장부가치측면과 회계이익측면에서 각각의 감면제도가 기업가치에 미치는 정도의 차이가 있는 것으로 나타났다. 이는 정책당국에서 간접감면제도의 조세정책적 실효성을 재검토 할 필요성의 여지를 가질 수 있음을 보여주고 있다.

• 한국경영과학회지
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• 제21권3호
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• pp.215-225
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• 1996

For an undirected stochastic network G, the 2-terminal reliability of G, R(G) is the probability that the specific two nodes (called as terminal nodes) are connected in G. A. typical network reliability problem is to compute R(G). It has been shown that the computation problem of R(G) is NP-hard. So, any algorithm to compute R(G) has a runngin time which is exponential in the size of G. If by some means, the problem size, G is reduced, it can result in immense savings. The means to reduce the size of the problem are the reliability preserving reductions and graph decompositions. We introduce a net set of reliability preserving reductions : the $K^{4}$ (complete graph of 4-nodes)-chain reductions. The total number of the different $K^{4}$ types in R(G), is 6. We present the reduction formula for each $K^{4}$ type. But in computing R(G), it is possible that homeomorphic graphs from $K^{4}$ occur. We devide the homemorphic graphs from $K^{4}$ into 3 types. We develop the reliability preserving reductions for s types, and show that the remaining one is divided into two subgraphs which can be reduced by $K^{4}$-chain reductions 7 polygon-to-chain reductions.

• Nutritional Sciences
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• 제1권1호
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• pp.3-7
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• 1998

The aim of the present investigation was to see whether an anabolic steroid, nandrolone phenylpropionate (NPP), exerts protienanabolic effects under such adverse nutritional conditions as protein deficiency and protein-energy malnutrition in male rats. feeding on a low-protein (8% casein) diet resulted in a marked reduction in body weight gain that was associated with reductions in body protein and protein content of gastrocnemius muscle. Administration of NPP (4 mg/kg body weight) did not alter muscle and body protein depletion induced by a low-protein diet. 50% food restriction caused reductions in body protein and in protein content of gastrocnemius muscle. These reductions were partially prevented by NPP (4 mg/kg body weight). Food restriction did not affect plasma concentration of corticosterone, insulin, or tetosterone plus dihydrotestosterone. On the other hand, neither plasma concentration of corticosterone nor insulin were affected by NPP. The present results show that anabolic steroids do not express anabolic effects under conditions of protein deficiency, but in protein-energy malnutrition, anabolic steroids exert their anabolic effects even in male rats.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.289-303
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• 2004

As needs for telecommunications services diversify, an increasingly wide range of telecommunications services is becoming available in the market. Any subscriber can find a service to satisfy his/her telecommunication requirements and competition between providers to retain heavy users is increasing. Service price reductions are one retention strategy, although price reductions for one service can affect the individual-level usage for other services. Price reductions can also be imposed on a service provider by regulation. For these reasons, understanding how price reductions affect service usage is of growing importance to the telecommunications industry for purposes of pricing and tariff development. In this paper, we develop an individual-level usage model for telecommunications services and analyze the effects on usage of a price reduction. We apply the model to age-stratified aggregate traffic data for a Korean mobile telecommunication service provider. Finally, we develop a model to support a market segmentation and price reduction strategy.

• Advances in materials Research
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• 제13권3호
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• pp.161-171
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• 2024

This study aimed to investigate the effect of physicochemical properties and mix ratios of iron ore (oxide feed): coke (reductant) on the carbothermic reductions of iron ore. Coke size was fixed at ≤63 ㎛ while iron ore size varied between 150-63 ㎛ and ≤63 ㎛ respectively. Mix ratios were changed from 100:0 (reference) to 80:20 and 60:40 while the temperature, heating rate and soaking duration in muffle furnace were fixed at 1100 ℃, 10 ℃/min and 1 hour. Particle size analyzer, XRF, CHNS and XRD analyses were used for determination of raw feed characteristics. The occurrence of phase transformations from various forms of iron oxides to iron during the carbothermal reductions were identified through XRD profiles and supported with weight loss (%). XRF analysis proved that iron ore is of high grade with 93.4% of Fe₂O₃ content. Other oxides present in minor amounts are 2% Al₂O₃ and 1.8% SiO₂ with negligible amounts of other compounds such as MnO, K₂O and CuO. Composite pellet with finer size iron particles (≤63 ㎛) and higher carbon content of 60:40 exhibited 45.13% weight lost compared to 32.30% and 3.88% respectively for 80:20 and 100:0 ratios. It is evident that reduction reactions can only occur with the presence of coke, the carbon supply. The small weight loss of 3.88% at 100:0 ratio occurs due to the removal of moisture and volatiles and oxidations of iron ore. Higher carbon supply at 60:40 leads into better heat and mass transfer and diffusivity during carbothermic reductions. Overall, finer particle size and higher carbon supply improves reactivity and gas-solid interactions resulting in increased reductions and phase transformations.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2005년도 춘계 학술발표회 논문집
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• pp.148-151
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• 2005

Field-scale DNAPL dissolution is controlled by the topology of DNAPL distributions with respect to the velocity field. A high resolution percolation model was developed and employed to simulate the distribution of DNAPL within source zones. Statistically anisotropic permeability values and capillary parameters were generated for 10${\times}$10${\times}$10 m domains at a resolution of 0.05 to 0.1 m for various statistical properties. TCE leakage was simulated at various rates and the distribution of residual DNAPL in 'fingers' and 'lenses' was computed. Variations in finger and lens geometries, frequencies, average DNAPL saturations, and overall source topology were predicted to be strongly influenced by statistical properties of the medium as well as by injection rate and fluid properties. Model results were found to be consistent with observations from controlled DNAPL release experiments reported in the literature. The computed distributions of aquifer properties and DNAPL were utilized to perform high-resolution numerical simulations of groundwater flow and dissolved transport. Simulations were performed to assess the effect of grout or foam injection in bore holes within the source zone and of shallow point-releases of fluids with various properties on dissolution in DNAPL dissolution rate, even for widely spaced injection points. The results indicate that measures that induced partial flow reductions through DNAPL source zones can significantly decrease dissolution rates from residual DNAPL. The benefit from induced partial flow reductions is two-fold: 1) local flow reduction in DNAPL contaminated zones reduces mass transfer rates, and 2) contaminant flux reductions occur due to the decrease in groundwater velocity

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.44-45
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• 2020

Korea has the fourth highest CO₂ emission among OECD countries in 2018, As of 2019, total greenhouse gas emissions per capita increased by about 98.2% in comparison to 1990. Korea has promised a 37% reduction in greenhouse gas emissions in 2030 from the projected Paris Climate Change Accord. Currently, many countries use the emissions trading system(ETS) for international carbon management. In 2015, ETS has been implemented in Korea, and the importance of calculating CO₂ emissions from construction machinery has increased. So, we require an accurate calculation of the environmental charges through the allocated CERs. Using the CER price and related search keywords, this paper derive about prediction models of CER price and compare and focus on more accurate prediction about CER price. By this method, the budget needed to establish the initial construction process plan can be calculated based on more accurate predicted CER price.

• 한국항해항만학회지
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• 제48권2호
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• pp.97-103
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• 2024

As there is growing concern about the environmental impact of greenhouse gas emissions from ships, the International Maritime Organization (IMO) has introduced several regulations targeting reductions in carbon dioxide emissions of 50% by 2050. This study pays particular attention to the carbon intensity indicator (CII) and investigates the impact of slow steaming, one of the short-term measures in the regulation, on containership operations. To this end, a dataset of 8 containerships with various ages and sizes was collected. Based on operation data in 2021, the CII ratings of the containerships were estimated in the business-as-usual scenario for the 2023-2030 period. Then, the speed reductions required to keep the minimum CII rating were calculated for individual containerships. Finally, working day losses resulting from the speed reductions were calculated. The findings in this study were threefold. First, it was found that containerships will undergo degradation in the CII rating every 3 or 4 years without slow steaming. Second, a speed reduction of 2 knots between 2023 and 2030 is required to keep the minimum CII rating. Finally, speed reductions result in the loss of as many as 6 or 7 working days per year.

• 한국재난정보학회 논문집
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• 제8권1호
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• pp.27-35
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• 2012

본 연구에서는 환경 문제로 대두되고 있는 도로 교통 소음을 저감하기 위한 노력으로 저소음 포장 공법인 마이크로 서피싱 포장 공법을 활용한 저소음 포장의 현장 적용과 소음 저감효과를 평가하고자 하였다. 마이크로 서피싱 포장의 적용을 위해 소음의 발생 메커니즘을 분석하고, 포장의 최적화를 위해 골재의 입형과 입도를 변경하고, 야간공사에 적합한 배합과 공법을 제시하였다. 소음 측정 결과 고정식 측정의 경우 2dB에서 7.1dB까지의 소음 저감효과가 측정되었다. 고정식 측정결과는 바람의 영향, 차량통행량 등의 다양한 변수가 작용하여 편차가 큰 것으로 예상된다. 또한, 이동식 측정의 경우는 80km/h의 시속에서 5.6dB 에서 6.7dB의 소음 저감효과가 있었다. 이동식 측정결과는 반복측정에 대한 편차가 비교적 적으며, 각각의 차선에서 측정된 결과로 일정하여 도로 포장의 소음 감소효과를 측정하는데 보다 합리적이라 판단된다. 따라서 마이크로 서피싱 포장의 소음 저감효과를 확인할 수 있었으며, 표면처리 공법으로 예방적 보수를 실시하여, 경제적이고 지속적인 저소음 포장으로서의 기능을 할 수 있을 것으로 평가된다.