• 한국의료질향상학회지
• /
• 제7권2호
• /
• pp.218-228
• /
• 2000

Background : Among 'structure', 'process' and 'outcome' approaches, outcome evaluation is considered as the most direct and best approach to assess the quality of health care providers. Risk-adjustment is an essential method to compare outcome across providers. This study has aims to judge performance of hospitals by severity adjusted mortality rates of coronary artery bypass graft (CABG) surgery. Methods : Medical records of 584 patients who got the CABG surgery in 6 general hospitals during 1996 and 1997 were reviewed by trained nurses. The MedisGroups was used to quantify severity of patients. The predictive probability of death was calculated for each patient in the sample from a multivariate logistic regression model including the severity score, age and sex. For evaluation of hospital performance, we calculated ratio of observed number to expected number of deaths and z score [(observed number of deaths - expected number of deaths)/square root of the variance in the number of deaths], and compared observed mortality rate with confidence interval of adjusted mortality rate for each hospital. Results : The overall in-hospital mortality was 7.0%, ranged from 2.7% to 15.7% by hospital. After severity adjustment the mortality by hospital was from 2.7% to 10.7%. One hospital with poor performance was distinctly divided from others with good performance. Conclusion : In conclusion, severity-adjusted mortality rate of CABG surgery might be applied as an indicator for hospital performance evaluation in Korea. But more pilot studies and improvement of methodologies has to be done to use it as quality indicator.

• 대한토목학회논문집
• /
• 제14권6호
• /
• pp.1273-1279
• /
• 1994

비보호좌회전이 가능한 차선을 비보호좌회전 교통만 이용하게 되는 경우는 3가지가 있다. 이 경우에는 lane grouping 때 비보호좌회전과 직진이 같은 차선군에 포함될 수 없기 때문에 비보호좌회전을 직진과 분리하여 별도의 포화교통량과 좌회전 보정계수를 구한다. 따라서 비보호좌회전 교차로의 용량분석시 이와 같은 경우를 판별해 내기 위해서는 그 임계값(threshold)역활을 하는 비보호좌회전의 용량을 알아야 한다. 또 이 용량으로부터 비보호좌회전의 포화교통량과 보정계수를 바로 구할 수 있다. 뿐만 아니라 이 용량은 비보호좌회전 운영방식의 타당성을 검토하는 일차적인 기준으로 사용될 수 있다. 본 연구는 비보호좌회전의 용량에 결정적인 영향을 주는 임계차간시간과 좌회전 평균 최소 차두시간을 현장측정 자료를 이용하여 구하고, 이를 이론적인 모형에 적용시켜 비보호좌회전의 용량을 구했으며, 이로부터 이 3가지 경우에 대한 포화교통량과 좌회전 보정계수를 구하는 방법을 제시했다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
• /
• pp.43-48
• /
• 1992

The automation system oriented as one of the second year automation projects for the small and medium sized enterprises(SME) was developed for the improvement of the production rate and cut the required manpower in the field of the relay which is one of the small electric components used in various industrial fields. The objectives of this study are not only improving the international competition of the relay itself but also partially solving the technical and financial problems featured by common bottlenecks of the SME for efficient assembly automation. For the purpose of these objectives, several topics are studied as followings. - Analyzing the adjustment process and determining the specification of the automation system. - Determining the layout for the automation system to meet the determined specification. - Detail design of the automation system for relay adjustment and inspection. - Control system design - Automation system development and performance test.

• Journal of Biosystems Engineering
• /
• 제32권6호
• /
• pp.383-388
• /
• 2007

In precision farming, proper calibration and operation of a variable rate machine are critical to reduce input of agrochemicals and to ensure productivity and quality of agricultural products. As an effort to introduce precision farming to rice production in Korea, a pneumatic granular applicator was developed. This investigation intended to evaluate the application performance such as application accuracy, application uniformity and to suggest how to adjust the blow-heads to get uniform application pattern, and to suggest a practical way of adjustment of the blow-heads for uniform application. Tests to evaluate the application performance were conducted. The application uniformities (CV) in both transverse direction and longitudinal direction were less than 15% and application accuracy was greater than 81%. A simple method for adjusting the inserting length of blow-heads was suggested.

• The Korean Journal of Ecology
• /
• 제24권4호
• /
• pp.223-226
• /
• 2001

The leaf water relations and photosynthetic rate during acute soil drying were compared in potgrown grapevine cultivars, Vitis vinifera cv. Chardonnay and V. vinifera cv. Riesling. Leaf water potential in Riesling decreased significantly from day 2 after water had been withheld, while in Chardonnay leaf water potential for the water-stressed plants was almost identical with that in well watered plants during the first 4 days. Higher stomatal conductance and photosynthetic rate in Chardonnay than Riesling were observed until day 3 after withholding water. Photosynthetic rate in water-stressed Chardonnay was not different from that in control plants until day 3 after withholding water, while that in water-stressed Riesling was reduced markedly from day 2. In Riesling, osmotic potential at turgor loss point was not changed irrespective of watering conditions. However, in Chardonnay osmotic potential at turgor loss point decreased more in the water stressed conditions than in well watered conditions. The osmotic adjustment in Chardonnay under water stress conditions must contribute to the maintenance of higher stomatal conductance and photosynthetic rate than those in Riesling for a significant period of the drying process. Though difference in stomatal conductance between the two cultivars was shown in the process of soil drying, stomatal conductance of both cultivars responded to vapor pressure difference between leaf and ambient air, rather than soil water status and leaf water potential.

• 한국산업정보학회논문지
• /
• 제27권2호
• /
• pp.11-24
• /
• 2022

LMS 기반의 온라인 평가를 위해 출제되는 문제들은 교수자가 직접 출제하거나 또는 카테고리별로 나뉘어진 문제은행에서 난이도에 따른 자동 출제 방식을 주로 이용한다. 이중에서 난이도에 따른 자동출제 방식은 평가자들에게 출제되는 문제가 서로 다를수 있기 때문에 무엇보다 객관적이고 효율적인 방법으로 문제의 난이도를 관리하는 것이 중요하다. 본 논문에서는 문제의 정답률뿐만 아니라 해당 문제를 해결하는데 사용된 소요시간을 같이 고려한 난이도 재조정 알고리즘을 제시한다. 이를 위해 머신러닝의 로지스틱 회귀 분류 알고리즘을 이용하였으며, 학습모델의 예측 확률값을 기반으로 기준 임계값을 설정하여 각 문항별 난이도 재조정에 활용하였다. 그 결과 정답률에만 의존한 문항별 난이도에 많은 변화가 일어남을 확인할 수 있었다. 또한 조정된 난이도의 문제를 이용하여 그룹별 평가를 수행한 결과, 정답률 기반의 난이도 문제에 비해서 대부분의 그룹에서 평균 점수가 향상됨을 확인할 수 있었다.

• 한국자원식물학회지
• /
• 제7권1호
• /
• pp.97-101
• /
• 1994

The effects of NaCl salinity on the leaf photosynthesis and water relation of two cultivars of rice(Oryza sativa L.) , the salt-tolerant cultivar Seohae and the salt-senstive cultivar Iri-380 were exam-ined. Two cultivars of rice were grown for 14 days in nutrient solution at SOmM NaCl. Comparing theieaf Na content of two cultlvars, Seohae showed high accumulation of Na content in the leaf blade, while Iri-380 showed low. The Na content in leaf blade reduced the rate of leaf photosynthesis. Salt-tolerant cultivar Seohae was less decreased the rate of leaf photosynthesis than salt- sensitive cultivarIri-380. And Seohae showed larger decreased the osmotic potential in the leaves than Iri-380. This in-dicates that in the salt-tolerant cultivar, osmotic adjustment is developed under saliniEation.

• Management Science and Financial Engineering
• /
• 제7권2호
• /
• pp.73-90
• /
• 2001

This paper presents the reliability models for redundant systems composed of repairable components whose failure time and repair time distributions are phase-type. It is shown that the distribution of time to system failure is also phase-type. The dependency between components are considered and integrated into the model by the used of the rate adjustment factor. The phase-type representation is constructed for the system through algebraic operations on the parameters of components\` failure time and repair time distributions and the corresponding rate adjustment factors. Types of system structures considered are parallel, k-out-of-N system with load sharing scheme and standby system with operation priority.

• 한국학교보건학회지
• /
• 제23권1호
• /
• pp.41-52
• /
• 2010

Purpose: The objective of this study is to investigate the relationship between middle and high school students' internet addiction, social support, self-efficacy and school life adjustment. Data were collected by self-administered questionnaires at middle and high school students located in Seoul and the metropolitan areas. Methods: The response rate is 94.8% (474 cases). The internet addition was measured by K Scale. The various methods of analysis were used, for example, frequency analysis, t-test, analysis of variance, and multiple regression analysis. Results: First, the mean score of internet addiction level is 2.07 in 5 Likert scale. the internet addiction level of the male students are higher than female students (p<.05). Second, as a result of classification of internet addiction groups by K Scale, 11 students (2.3%) are included in high risk group, 27 students (5.7%) are in potential risk group, 436 students (92.0%) are in general group. Third, the level of social support and self-efficacy of middle and high school students are very high. The difference of social support by internet addiction groups was not statistically significant. But, the difference of self-efficacy by internet addiction groups was statistically significant. The level of self-efficacy of the students in general groups are more higher than in high risk group and in potential risk group (p<.01). Fourth, the difference of school adjustment by internet addiction groups was very statistically significant. The level of school life adjustment of the students in general groups are more higher than in high risk group and in potential risk group (p<.01). Fifth, the internet addiction have a negative correlation with school life adjustment. And the social support and self-efficacy have a positive correlation with school life adjustment (p<.01). Finally, in stepwise multiple regression analysis, the internet addiction affects negatively on the school adjustment. And the support of teacher among three types of them affects positively on the school life adjustment. And the social self-efficacy among two types of them affects positively on the school adjustment (p<.01). Conclusion: to adjust desirably the school environment of the middle and high school students, optimal and efficient management of internet addiction was needed in the future and the improvement and promotion of social support and social self-efficacy of the students was also demanded.

• 한국건설관리학회논문집
• /
• 제6권1호
• /
• pp.186-194
• /
• 2005

본 연구는 건설공사 하도급계약의 당사자인 수급인과 하수급인간의 하도급계약금액 조정과 관련하여 발생하는 원인을 검토하고, 분쟁을 예방하기 위한 하도급대금조정 관련 법규의 개선방안을 제시하는 것을 목적으로 한다. 본 연구는 문헌연구, 하도급계약 법규에 관한 구조와 맥락의 분석 그리고 설문조사의 방법에 의하여 진행되었으며, 주요한 연구결과는 다음과 같다. (1) 발주자와 수급인의 계약금액 조정이 이루어지는 경우 그 내용을 하수급인에게 통지하도록 하는 절차에 관한 조항을 하도급법과 건설표준하도급계약조건에 규정하여야 한다. (2) 하수급인이 하도급계약 내용의 변경 및 그에 수반되는 하도급대금 조정을 청구할 수 있도록 하는 절차를 건설표준하도 급계약조건에 규정하여야 한다. (3) 하도급대금 조정에 관한 기준을 명확히 하기 위하여 건설표준하도급계약조건에서 사용되고 있는 불확정 개념인 단가, 낙찰률 등 용어의 정의를 명확히 하였다. (4) 수급인의 귀책으로 인해 발생하는 연장비용의 부담은 수급인이 부담하도록 하여 부담의 주체를 명확히 하고 연장비용의 산정기준으로 재정 경제부 제정 실비산정규정을 적용하여야 한다.