• 한국시뮬레이션학회논문지
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• 제27권3호
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• pp.45-52
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• 2018

대기행렬에 고객 (또는 패킷 등)이 몰리는 오버로드(overload)가 발생하는 경우 긴 대기열이 발생하여 서비스 품질에 좋지 않은 영향을 줄 수 있다. 오버로드 상황에서 혼잡을 완화하기 위해 대기하는 고객숫자에 기반한 다양한 오버로드 제어 정책들이 고안, 적용되고 있다. 본 연구는 대기 중인 고객 숫자에 한계점 (threshold)을 두고, 한계점을 넘으면 서비스 속도를 빠르게 하거나 고객의 도착 간격(시간)을 증가시키는 제어정책을 대상으로 한다. 이러한 정책을 갖는 M/G/1 대기행렬에 대해 바쁜 기간(busy period)을 분석하는데, 연구결과는 비용구조가 주어졌을 때 최적 시스템 제어 정책을 찾는데 필수적이다.

• 대한기계학회논문집
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• 제16권7호
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• pp.1285-1293
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• 1992

본 연구에서는 glass/epoxy 직조된 복합재료에 있어서 원공 및 판폭의 크기가 노치강도에 미치는 영향을 명확히 하고, 또한 노치강도 및 파괴조건과 위에서 언급한 특성길이와의 관계를 검토하였다.

• 복식
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• 제55권5호
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• pp.87-100
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• 2005

This study was to provide the fundamental data for a scientific and rational clothing construction by investigating the length variation of the upper body surface, using the method of surgical tape. The subjects were 15 early elementary schoolgirls in Busan area classified by three somatotypes, Arm-movements were consisted of 6 types. The statistical analyses used in this study were mean, standard deviation and the ANOVA and LSD procedure. The results of the analysis of the length of the upper body surface are as follows: By arm-movements, in the items of horizontal, front neck base girth, back upper bust girth, back bust girth and back under bust girth were increased and the other standard lines were apt to be decreased. In the items of vertical, all standard lines of front side and side seam length showed increased, the lines of bark side were apt to be decreased. The shoulder length represented the maximum rate of decrease($-36.59\%{\~}-48.98\%$) in M6($180^{\circ}$) and the side seam showed the maximum rate of increase($49.74\%{\~}59.22\%$) in the same movement.

• 대한전자공학회논문지SD
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• 제49권1호
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• pp.25-34
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• 2012

본 논문은 고속 WPAN 시스템에 대한 가변 길이 8-병렬 리드-솔로몬(RS) 복호기에 관한 일반적인 구조를 제안한다. 제안된 구조는 RS(255,239) 코드뿐만 아니라 다양한 단축화 RS 부호들을 지원 할 수 있다. 특히, 가변길이 구조는 다양한 단축화 RS 부호에 대해 가변적인 낮은 지연을 제공하며, 8-병렬 구조를 적용하여 높은 데이터 처리율을 제공한다. 제안된 RS 복호기는 90-$nm$ CMOS 표준 셀 기술을 사용하여 성능 분석을 수행하였고, 클록 주파수 300$MHz$에서 19-$Gbps$ 데이터 처리율을 제공한다.

• 농업과학연구
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• 제33권2호
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• pp.159-166
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• 2006

Threshing loss was increased due to dropping of the threshing efficiency when the 4 row head-feed combine harvested 5 row rice to improve harvesting performance of a combine. Reasonable design criteria were examined to determine the ranges of both of feed rate and the length of threshing drum for the 4 row head-feed combine being used as a 5-row combine. Harvesting performance increased as working width or working speed increased, it resulted in 15% increase when the working width increased from 4 row to 5 row. Harvesting operations of the 4 row combine performed normally in the 4 row rice in threshing loss less than 1%, however, threshing loss increased to 2.25% in the 5 row due to poor threshing efficiency. The length of threshing drum was increased from 710 mm to 810 mm as well as the speed of crop feed chain was increased from 0.61 m/s to 0.75 m/s so as to improve the poor threshing efficiency resulted from the enlarged working width from the 4 row to the 5 row, which would decrease threshing loss less than 1%.

• 국제물리치료학회지
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• 제10권4호
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• pp.1873-1878
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• 2019

Background: Walking is a complex activity. The main components of walking include balance, coordination, and symmetrical posture. The characteristics of walking patterns of stroke patients include slow walking, measured by gait cycle and walking speed. This is an important factor that reflects post-stroke quality of life and walking ability. Objective: This study aimed to examine the effect of deep lumbar muscle stabilization exercise on the spatiotemporal walking ability of stroke patients. Design: Quasi-experial study Methods: The experiment was conducted 5 times per week for 4 weeks, with 30 minutes per session, on 10 subjects in the experimental group who performed the deep lumbar muscle stabilization exercise and 10 subjects in the control group who performed a regular exercise. Variables that represent the spatiotemporal walking ability (step length, stride length, step rate, and walking speed) were measured using GAITRrite before and after the experiment and were analyzed. Results: There was a significant difference in the pre- and post-exercise spatiotemporal walking ability between the two groups (p<.05). Furthermore, there was a significant difference in the step rate and walking speed between the two groups (p<.05). Conclusions: Deep lumbar muscle stabilization exercise is effective in improving the walking ability of stroke patients. Therefore, its application will help improve the spatiotemporal walking ability of stroke patients.

• 한국수정란이식학회지
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• 제25권1호
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• pp.21-27
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• 2010

The increase in the total number of cows on farms, which breed Korean Native Cattle (KNC), is associated with many problems. In particular, the services per conception and calving interval have increased. In this study, we examined the effect of dietary supplementation with vitamin and mineral complex on the estrus rate, pregnancy rate, gestation length, and birth weight of KNC calves. Multiparous or primiparous KNC were divided into 3 groups with 40 heads per group. Experimental group 1 was administered a consisting of 35,000 IU vitamin A, 100 IU vitamin E, 200 mg $\beta$-carotene, 200 mg Zn methionine, and 1.5 mg Se. Experimental group 2 was administered a vitamin complex (100 g/day) consisting of 100 IU vitamin E and 200 mg $\beta$-carotene. In the case of multiparous KNC, the estrus detection rate in the control group was 90.0% and those in the experimental groups were 75.0% to 95.0%. However, the first-service pregnancy rate after parturition in the control group was 41.2%, which was significantly lower than that in the experimental groups (71.0% to 76.7%; p<0.05). The average duration of pregnancy in the group supplemented with the vitamin complex was days, which was similar to that in the case of the control group. The birth weight of calves from cows fed with vitamin complex was 25.3 to 27.0 kg, which was similar to that in the case of the control group (25.2 to 26.0 kg). In the case of primiparous KNC, no differences in the estrus rate, pregnancy rate, gestation length, or the birth weight of calves were noted between the groups. Thus, dietary supplementation vitamin and mineral complex have no effect on the reproductive efficiency in primiparous cows, but the pregnancy rate was observed to have increased in multiparous KNC with these supplements.

• 대한간호학회지
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• 제33권1호
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• pp.122-129
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• 2003

Purpose: The purpose of this study is to examine the difference of direct nursing activity and patient outcomes as mortality rate, complication rate, readmission rate and length of stay related to graded fee of nursing management for inpatient. Method: The subjects of this study were 44 general hospitals with more than 500 beds. Data totaled to 86,044 claims provided to inpatients in Jan. 2001 requested by an electronic data interchange from a Health Insurance Review Agency. The data was analyzed by SPSS win(ver.10.0) and statistical methods used were frequency, one-way ANOVA, $X^2$-Test and regression. Result: Synthetic judgment through performance index and 95% confidence interval, direct nursing activity showed to provided adequate quality of nursing care on 2nd, 3rd, 4th and 6th nursing degree. Also, patient outcomes showed difference by graded fee of nursing management for inpatient. Mortality rate of 2nd was the lowest with P.I. 67.9, 3rd, 5th, 6th, 4th in order. In case of complication rate, 2nd, 3rd and 4th were lower than other nursing degree. Readmission rate of 4th and 5th was the lowest. Length of stay of 2nd was the shortest with P.I. 88.3, 3rd, 4th, 5th, 4th, 6th in order. Conclusion: The findings from this study showed that, the higher nurse-to-patient ratio, the greater amount of direct nursing care activity for the patient. Also, the more direct nursing activities influenced a lower mortality rate, complication rate and readmission rate, shorter length of stay.

• 한국산업보건학회지
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• 제11권1호
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• pp.34-41
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• 2001

Passive samplers have been used for personal, indoor, and outdoor air monitoring of VOCs at ppb concentrations in community and office environments. The path length of modified passive sampler was shortened, so it was intended to increase an uptake rate. The performance of the modified 3M 3500 organic vapor monitor(OVM) as a tool for assessing exposures to toxic air pollutants in nonoccupational community environments was evaluated using combined controlled test atmospheres of six selected target volatile organic compounds(VOCs): benzene, methyl tert-butyl ether(MTBE), chloroform, 1,4-dichlorobenzene, tetrachloroethylene, and toluene. The experiments were conducted by exposing the dosimeters to concentrations of $50{\sim}100{\mu}g/m^3$ on six face velocity(0.00, 0.02, 0.06, 0.12, 0.20, 0.30 m/sec) for 24 hours. If the uptake rate was increased, that means that we could use the passive sampler more effectively. The uptake rates were increased linearly according to reduce the path length. Although the diffusion path length was shortened, the change of uptake rate was within ${\pm}25%$ of theoretical value, indicating that the modified passive sampler(TM) can be effectively used over the range of concentrations and environmental conditions tested with a 24-h sampling period if the face velocities were over 0.12 m/s for 6 components of VOCs. But when the face velocities were less than 0.12 m/s, uptake rates were reduced more than expected values. So, the passive sampler with the shortened path length should be used at indoor or outdoor environment where the face velocity should be over about 0.10 m/s. If the path length was shortened more, the uptake rate was more effected by starvation.

• 한국작물학회지
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• 제66권3호
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• pp.183-189
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• 2021

볍씨 종자의 최아정도 및 최아 손상정도에 따른 출현율 및 초기생육변화를 분석한 결과는 다음과 같다. 1. 볍씨 최아 길이가 길수록 출현율은 다소 감소하였으며 생육온도가 18℃ 이상으로 높을수록 차이가 큰 것으로 나타났다. 2. 최아 길이가 길수록 초장신장 속도가 감소하였으며 생육온도가 21℃ 이상으로 높을 시 최아길이 3 mm에서 초장이 크게 감소하였다. 3. 최아길이에 따른 엽수변화는 없었으나 줄기 두께 및 줄기 건물중, 뿌리 건물중은 최아길이가 길수록 유의하게 감소하였다. 4. 최아 손상정도가 증가할수록 출현율은 유의하게 감소하였으며 생육온도가 높을수록 감소폭은 증가하으며 엽수변화는 없었으나 줄기 두께 및 줄기 건물중, 뿌리 건물중은 최아 손상도가 길수록 유의하게 감소하였다. 최아 길이 및 종자 손상정도별 뿌리 건물중과 줄기 건물 중 변화는 유의한 정의 상관관계를 보였다.