• 한국가금학회지
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• 제15권3호
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• pp.219-227
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• 1988

본 실험은 사료첨가제로 사용되는 인산칼슘제에 들어있는 Ca과 P의 생물학적 이용성을 측정 비교하고자 실시하였다. 5일령의 수평아리를 사용하여 12 일간의 실험기간 후에 경골의 회분함량율 기준으로 하여 표준계선에 의한 least square방식으로 측정한 이용성의 결과는 다음과 같다. 1. P의 이용성은 DiCa-P첨가제가 각각 77.1, 91.0, 96.4 그리고 95.5％를 나타냈고 TriCa-P첨가제는 각각 94.1, 95.0 및 99.5％를 나타냈다. 2. Ca의 이용성은 DiCa-P 첨가제에서 각각 78.3, 234.1, 87.6 그리고 244.5％였고 TriCa-P첨가제는 각각 99.5, 84.0 및 101.5 ％였다. 3. 전반적으로 TriCa-P첨가제가 DiCa-P첨가제보다 이용성이 약간 높게 나타났다. 4. 국산과 외국산 인산칼슘제의 이용성의 차이는 없었다.

• 재무관리연구
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• 제25권1호
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• pp.109-140
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• 2008

본 연구는 투자자간의 의견차이가 수익률의 비대칭적 변동성 현상에 영향을 주는지 검증하고, 정보량이 비대칭적 변동성에 미치는 영향을 검증하였다. 2000년 1월 4일부터 2005년 12월 29일까지의 유가증권시장 주가지수의 일별 종가와 거래량을 표본자료로 이용하였으며, 일별 거래량과 시장가치 수준별로 개별기업을 대상으로 각각 포트폴리오를 구성하여 분석하였다. 실증분석에서 TGARCH 모형을 기본모형으로 이용하였으며, 투자자간 의견차이의 대용변수인 거래량을 추가한 수정모형을 통하여 분석하였다. 주가지수를 대상으로 기본모형을 분석한 결과는 비대칭적 변동성이 존재하는 것으로 나타났으나, 수정모형의 분석 결과에서는 비대칭적 변동성이 유의적으로 감소되는 것으로 나타났다. 그리고 포트폴리오를 대상으로 분석한 결과는 정보량(거래량, 시장가치)이 많을수록 비대칭성 계수와 비대칭성 비율이 대체적으로 높은 것으로 나타났으며, 또한 기본모형에 비해 수정모형에 의해 추정된 비대칭성 계수와 비율이 제한적이나마 유의적으로 감소하는 것으로 나타났다. 이상의 결과에서 우리나라 증권시장에서 투자자간 의견차이가 비대칭적 변동성을 설명하는 요인 중의 하나라고 할 수 있으며, 정보량이 비대칭적 변동성에 제한적으로 영향을 미치는 것을 알수 있었다. 한편, 시장가치가 높은 포트폴리오일수록 비대칭적 변동성이 높게 나타났는데 이는 투자자간 의견차이 뿐만 아니라 정보의 신뢰성 차이에 기인한 투자자들의 의견수정 정도에 의해 나타난 것으로 사료된다.

• 대한임상독성학회지
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• 제9권1호
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• pp.26-29
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• 2011

Purpose: The role of a point of care test (POCT) is currently becoming important when treating patients and making decisions in the emergency department. It also plays a role for managing patients presenting with drug intoxication. But the availability of the test has not yet been studied in Korea. Therefore, we investigated the utility and the availability of POCT for drug screening used in the emergency department. Methods: This was a retrospective study for those patients with drug intoxication between January 2007 and December 2010 in an urban emergency department. Results: Between the study period, 543 patients were examined with a Triage$^{(R)}$-TOX Drug Screen. Among those, 248 (45.7%) patients showed negative results and 295 (54.3%) patients showed positive results. The sensitivity of the test for benzodiazepine, acetaminophen and tricyclic antidepressants were 85.9%, 100%, 79.2%, respectively. Conclusion: POCT of drug screening in emergency department showed good accuracy especially in patient with benzodiazepine, acetaminophen and tricyclic antidepressant intoxication. Therefore, it can be useful diagnostic tool for the management of intoxicated patients.

• 한국컴퓨터산업학회논문지
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• 제3권1호
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• pp.77-84
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• 2002

다수의 서버를 클러스터로 연결하여 동시에 가동 할 경우 서버의 대수가 증가함으로 인해 발생하는 가용도 저하문제와 소프트웨어의 노화로 인하여 높은 가용도를 제공하기가 어렵다. 본 연구에서는 n대의 주 서버와 k 대의 여분서버로 구성되는 클러스터 웹 서버 시스템에서 가동되는 서버의 수, 여분서버의 수, 소프트웨어의 재활주기, 재활소요시간, 서버의 고장률, 서버의 수리율, 서버의 불안정률 등의 시스템 운영 파라미터에 기초하여, 소프트웨어의 재활정책에 대한 평가를 위해 평형 상태에서의 확률, 정지시간, 가용도, 손실비용 등을 계산하였다. 수학적 분석을 통해 다양한 시스템 운영 상태에 대한 실험을 통해 검증하였으며, 소프트웨어의 재활 정책에 의한 예방적 결함허용 기법이 시스템의 안정성에 중요한 요소임을 확인하였고, 또한 서버의 고장률 및 불안정률이 소프트웨어 재활 정책 결정에 중요한 요소임을 파악하였다.

• 지질공학
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• 제34권2호
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• pp.263-277
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• 2024

본 연구에서는 연천지역의 개발 가능한 지하수의 양을 추정하기 위해 분포형 수문모형 SWAT-K를 이용하여 토지이용, 토양분포 특성에 따른 함양량을 산정하였다. 모형의 검보정 결과 관측유량과 모의유량의 결정계수가 0.75~0.97로 양호하게 나타났으며 계산된 지하수 함양량은 겨울과 봄에 걸쳐 낮은 함양률을, 여름철에는 높은 함양률을 나타내는 시공간적 특성을 보였다. 계산된 연평균 함양률을 자연유량의 기저유출률과 비교하여 추정된 함양량의 타당성을 검토하였다. 지하수 개발가능량은 통계학적 빈도해석 기법을 이용한 10년 빈도 갈수시의 함양량으로 산정하여 연강수량의 11.5%인 것을 확인할 수 있었다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제15권4호
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• pp.282-288
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• 2015

Purpose : The purpose of this study is to compare the RAM (reliability, availability and maintainability) value in the acquisition phase with operational period for air weapon systems. The objective is to determine if the value of RAM is sufficient in the field, and look for any difference from the target value to some extent. Methods : For a case study, the ${\bigcirc}{\bigcirc}$ training aircraft is selected. Data from the two acquisition sources are utilized. One is the operational data in domestic aircraft through research and development, and the other is the data from imported aircraft. The two different sources were collected independently and distinctly. Results : According to the analysis, the domestic aircraft shows high deviation in RAM value compare to the imported systems. This is due to the effort of continuous reliability improvement. In the aspect of maintainability, the result shows a slight deviation, and the availability meets the requirement. Conclusion : The results of this study can be used in finding a way that can be effectively applied to the sustainability in the weapon system. If the RAM performance is significantly lower than the target value, then it is necessary to improve the design activities so that they can achieve the RAM target value.

• 한국도서관정보학회지
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• 제13권
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• pp.131-166
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• 1986

This study is designed to review the methods of duplicate copies decision making in the academic library. In this thesis, I surveyed queueing & markov model, statistical model, and simulation model. The contents of the study can be summarized as follows: 1) Queueing and markov model is used for one of duplicate copies decision-making methods. This model was suggested by Leimkuler, Morse, and Chen, etc. Leimkuler proposed growth model, storage model, and availability model through using system analysis method. Queueing theory is a n.0, pplied to Leimkuler's availability model. Morse ad Chen a n.0, pplied queueing and markov model to their theory. They used queueing theory for measuring satisfaction level and Markov model for predicting user demand. 2) Another model of duplicate copies decision-making methods is statistical model. This model is suggested by Grant and Sohn, Jung Pyo. Grant suggested a model with a formula to satisfy the user demand more than 95%, Sohn, Jung Pyo suggested a model with two formulars: one for duplicate copies decision-making by using standard deviation and the other for duplicate copies predicting by using coefficient of variation. 3) Simulation model is used for one of duplicate copies decision-making methods. This model is suggested by Buckland and Arms. Buckland considered both loan period and duplicate copies simultaneously in his simulation model. Arms suggested computer-simulation model as one of duplicate copies decision-making methods. These methods can help improve the efficiency of collection development and solve some problems (space, staff, budget, etc, ) of Korean academic libraries today.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.1019-1022
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• 2006

Satellite sea ice data from 1978 to the present reveal that the perennial ice (or ice that survives the summer) has been rapidly declining at almost 10% per decade. Warming due to increases in greenhouse gases in the atmosphere is now also being reflected in winter with drastic reductions in the maximum extent observed in 2005 and 2006. The retreat of the perennial ice also exposes more open water and has revealed an asymmetric distribution of chlorophyll a pigment concentration in the Arctic basin. Phytoplankton blooms are most dominant at high latitudes, partly on account of sea ice, but in the Arctic basin, it appears that pigment concentrations in the Eastern (Laptev Sea) Region are on the average three times higher than those in the Western (Beaufort Sea) Region. Such asymmetry suggests that despite favorable conditions provided by the melt of sea ice, there are other factors that affects the productivity of the region. The asymmetry is likely associated with much wider shelf areas in the East than in the West, with sea ice processes that inhibits the availability of nutrients near the surface in deep water regions, and river run-off that affects nutrient availability. The primary productivity in the pan-Arctic region have been estimated using the pigment concentrations and PAR derived from SeaWiFS data and the results show large seasonal as well as interannual variability during the 1998 to 2005 period. The data points towards increasing productivity for later years but with only 9 years of data it is too early to tell the overall effect of the sea ice retreat.

• Ecology and Resilient Infrastructure
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• 제5권1호
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• pp.11-18
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• 2018

Phosphorous remains as one of the most limiting nutrients to plant growth, second only to nitrogen. Research on use of biochar as a soil amendment for available phosphorus in temperate calcareous soils has limited studies compared with to tropical acidic soils. An incubation experiment to assess phosphorous availability in a biochar amended calcareous soil under inorganic (Fused superphosphate, FSP) and organic fertilizer (bone meal, BM) and respectively, at the dose of 40, 80 and $120mg\;P\;kg^{-1}$ was carried out. Soil was incubated at $25^{\circ}C$ for 70 days. Results show that the rate of increase in available P was proportional to the fertilizer application rate with or without biochar amendment. Biochar did not have a significant effect on soils amended with either fertilizeron the values of available P. However, time had a significant effect (p<0.001) on the amount of available P during the incubation period. Inorganic fertilizer treatments had recorded high amount of available P with time compared to organic fertilizer treatments. Organic fertilizer treatment sample were significantly not different from control and for most of the incubation time biochar acted as a soil conditioner. Further research is required to understand the holistic and long-term effect of biochar.

• 한국측량학회지
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• 제30권6_2호
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• pp.607-613
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• 2012

Ionospheric anomaly is one of the major error sources which deteriorate the GNSS performance. In the equatorial region, effects of the ionospheric plasma bubbles are of great interest because they are pretty common phenomena, especially in the period of the high solar activity. In order to evaluate the GNSS performance under circumstance of the bubbles, an ionospheric scintillation monitor has been developed and installed in Bangkok, Thailand. Furthermore, a model simulating the ionospheric delay and scintillation due to the bubbles has been developed. Based on these developments, the effects of the simulated plasma bubbles are analyzed and their agreement with the real observation is demonstrated. An availability degradation of the GPS ground based augmentation system (GBAS) caused by the bubbles is exampled in details. Finally, an integrated GPS/INS approach based on the Doppler frequency is proposed to remedy the deterioration.