• Safety and Health at Work
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• 제13권3호
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• pp.294-301
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• 2022

Background: In the early stage of the coronavirus disease 2019 (COVID-19) epidemic, small- and midsized enterprises (SMEs) may be an important transmission consideration. The study aimed to identify the pattern of COVID-19 prevention measures during the outbreaks in Daegu and Gyeongsangbuk-do at the early stage of COVID-19. Moreover, we investigated whether SME size and past experiences affected the preventive measures implemented in the region. Methods: A survey detailing the general characteristics and implementation of 12 preventive activities was conducted in 122 SMEs in Daegu and Gyeongsangbuk-do. The survey was analyzed by size and operation period. Results: The study subjects consisted of 53 (43.4%) workplaces with 1-5 employees, 50 (40.9%) workplaces with 6-30 employees, and 19 (15.6%) workplaces with 31-49 employees. The lowest three items among those surveyed were 'symptomatic workers to stay home for 3-4 days' (17.2%), 'work remotely' (18.9%), and 'video meetings' (20.5%). There were significant differences in the rate of several preventive measures implemented. The larger sized SMEs, the higher the number of implementations (p < 0.01). The operation period had no significant relationship with the implementation of preventive measures. The same pattern was observed in multiple generalized linear regression with covariate adjustment. Conclusion: Preventive measures among SMEs with fewer than 50 employees were identified. Even within SMEs, a gap in preventive measures according to size was confirmed. To prevent the spread of infection and protect workers' right to health, different support for different sized SMEs is necessary.

• 마이크로전자및패키징학회지
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• 제27권4호
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• pp.47-54
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• 2020

활성 도파로와 수동 도파로의 집적은 광집적 회로의 구성에서 필수적인 요소이다. 이를 구현하기 위한 여러 기술 중 버트 조인트는 상당한 장점을 가지고 있다. 그러나 버트 조인트 접합은 높은 광손실을 야기하며, 두 도파로 간의 정렬에 있어서 정확한 공정 제어가 요구되는 구조이다. 본 논문에서는 레이저 다이오드와 spot size converter (SSC)로 구성된 집적 소자를 시뮬레이션하기 위해 beam propagation method을 이용하였다. 상이한 모드 특성을 갖는 두 SSC를 레이저 도파로와 연결하고, 광결합 효율을 시뮬레이션 하였다. 큰 근접장 모드를 가지는 SSC는 낮은 광결합 효율을 보여주나, 원거리 발산각 패턴이 좁고 더 대칭적이다. 테이퍼 구조의 수동 도파로는 원거리 발산각 패턴을 열화시키지 않고 버트 조인트에서 도파로 오프셋의 무의존성과 광결합 효율을 향상시키기 위해 이용되었다. 이를 바탕으로 89.6%의 높은 광결합 효율과 16°×16°의 좁은 원거리장 발산각을 얻을 수 있었다.

• 한국의류학회지
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• 제29권8호
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• pp.1146-1157
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• 2005

As individual family has fewer children, market sectors targeting children's goods upgrade their products quality and price. Children's wear used to be for casual activity or going to school. Recently, occasions in which children are dressed up are getting increase, such as wedding, concert or family gathering. Therefore, the industry sector of formal wears for school boys are growing. The purpose of this study is to research and grading of formal wears for school boys to improve their fit and comfort. The selected items as formal wear were tailored jacket, tuxedo, tail coat and pants. Based on the grading increments of the industry, grading was done far 7 years and 11 years old school boy for each item. Like the pattern alteration, grading increments were tested and altered through wearing tests. The final increments were suggested as the 'researched grading increments'. The results and conclusions are: 1. Appropriate size allowance, ease amount and lengths for boys are different from those far adults. The difference should be applied for boy's wear. 2. Grading increments for an age group are different from other age group. For example increments of 7 from 9 are different from that of 11 from 9. It is because a certain part grows faster during a certain age whereas other part grows faster during different period. Therefore grading for children should reflect their growth rather than same size increments which is common in adult size chart.

• 한국정보통신학회논문지
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• 제23권12호
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• pp.1659-1665
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• 2019

본 논문에서는 WLAN (wireless local area network) 응용을 위한 소형 인쇄형 모노폴 안테나의 새로운 설계에 대해 연구했다. 선폭이 다른 패치와 계단 모양의 접지면이 있는 복사체는 안테나 크기를 줄이기 위해 사용된다. 안테나의 크기는 16 × 17 × 1 ㎣이며 포토리소그래피(photolithography) 기술로 제작되었다. 시뮬레이션 및 측정 결과가 잘 일치한다. 연구된 안테나의 공진 주파수는 약 5.2 GHz이며 측정 결과 1 GHz의 임피던스 대역폭을 가진다. 또한 측정된 방사패턴을 제시하고 필요한 WLAN 5 GHz 주파수 대역 (5.15 - 5.825 GHz)에서 측정된 이득 및 효율을 제시했으며, 5 GHz 대역 WLAN 안테나로 사용할 수 있음을 확인했다. 연구된 안테나는 소형, 경량, 저비용, 전방향성 복사패턴, 고이득 및 고효율을 갖는다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.480-485
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• 1998

Application of trans rectal ultrasonography to buffaloes (n=6) to follow the growth of large antral follicles individually, on each day of one interovulatory interval revealed that follicular turnover during oestrous cycle occured in waves. There was a predominance of a two-wave pattern (5/6 animals) compared to that of a three-wave pattern (1/6 animals). For two-wave pattern, the first wave emerged at Day $0.20{\pm}0.19$ (Day 0 = day of ovulation) and was marked by development of a dominant anovulatory follicle which grew in size from $5.40{\pm}0.24mm$ at the day of detection to a maximum diameter of $12.40{\pm}0.81mm$ on Day $8.60{\pm}1.57$, with a growth rate of $0.88{\pm}0.17mm/day$ and then regressed, with a mean persistence of $19.40{\pm}1.54$ days. The second wave emerged at Day $9.20{\pm}1.06$ and was marked by development of a dominant ovulatory follicle which grew in size from $4.20{\pm}0.37mm$ at the day of detection to a maximum diameter of $13.80{\pm}0.37mm$ on Day $21.00{\pm}1.38$, with a growth rate of $0.66{\pm}0.12mm/day$ and then ovulated on Day $21.60{\pm}1.25$, with a mean persistence of $11.80{\pm}1.39$ days. The maximum diameters attained and the growth rates of dominant anovulatory and dominant ovulatory follicles, and the mean number of follicles ${\geq}3mm$ diameter detected at the time of emergence of first and second waves ($11.80{\pm}1.74$ and $9.00{\pm}2.81$, respectively) were not significantly different. In the animal which showed a three-wave pattern, the first, second and third waves emerged on Days 1, 10 and 19, respectively. All animals, except one had at least one subordinate follicle in the first or second or both waves. The subordinate follicles increased in diameter over a few days and then regressed. The results indicate that in buffaloes, the follicular turnover during oestrous cycle occurs predominantly in a two-wave pattern.

• 한국전자파학회논문지
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• 제18권3호
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• pp.273-281
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• 2007

이 논문은 900 MHz대역의 RFID 태그용 다이폴 안테나를 설계하여, 이 안테나가 부착되는 물체에 의한 안테나의 성능이 실험적으로 평가되었다. 전기적 특성이 다른 유전체, 자성체 및 도체에 다이폴 안테나를 부착하였을 때, 부착된 매질의 종류, 크기 및 높이의 변화에 따라 안테나의 반사계수와 방사 패턴이 변화되는 것을 실험적으로 평가하였다 안테나가 유전체의 표면에 부착되었을 때, 측정된 반사계수와 방사 패턴은 비유전율의 영향으로 인해 약 40 MHz의 공진 주파수 편이와 약 $1\sim3dB$ 정도의 감쇠를 보였다. 부착 지판의 크기에 의한 주파수 편이가 관측되었으나, 부착 지판을 가진 다이폴 안테나의 측정된 방사 패턴은 부착 지판이 없는 다이폴 안테나의 방사 패턴과 유사하였다. 부착 지판이 도체나 자성체인 경우, 다이폴 안테나와 부착 지판 사이의 거리에 의한 주파수 편이와 위상차 때문에, 910 MHz에서 약 5 dB 이상의 방사 패턴 진폭의 저하가 관측되었다.

• 복식
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• 제55권6호
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• pp.24-37
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• 2005

This study was performed to get basic data for gloves size system and pattern planning suitable Korean hand shape. Data was collected through measuring hand size of man and woman from age 18 to 30 as subjects living in metropolitan area. by analysing the measured data, the difference in man and woman and the gloves size system was established. The results of study are as follows: 1. The Deviation of hand girths and hand lengths was larger than that of hand width in both man group and woman group. In all items. deviation in man was larger than woman. 2. In sex difference, there was difference between mall group and woman group in all items. In age difference, there was difference between mall group and woman group in mainly girth and the difference was bigger in group under 24 years old than in group over 24 years old. 3. The weight showed the highest $correlation(r{\geqq}0.8)$ with girths and high correlation with widths $(r{\geqq}0.7).$ The height showed the highest positive $correlation(r{\geqq}0.8)$ with and elbow length and high correlations with width and girths item. There were high positive correlation between vertical lengths in hand and between horizontal lengths but low correlation between vertical lengths and horizontal lengths. 4. The basic parts for gloves size system, hand lengths and hand girths were divided into 1cm interval. The results shouted that $91.0\%$ of man group were ranged from 18cm to 20cm section and $92.4\%$, of woman group were ranged from 16cm to 18cm section. 5. The interval which has the highest covet· rate was hand length 19cm and hand girth 20cm interval which covered $18.65\%$ of man group. The intervals which showed cover rate more than $5\%$ was total 7 and they covered $73.1\%$ of man group. The interval which has which has the highest cover rate was hand length 17cm and hand girth 17cm interval which covered $21.37\%$ of woman group. The intervals which showed cover rate more than $5\%$ was total 6 and they covered $72.5\%$ of total woman group.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1638-1652
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• 2000

Prolific females require better nutrition and feeding practice because of larger litter size and the substantial decline in body fat. Life-time pig output will be compromised if body protein and fat are not properly managed. First litter females are especially vulnerable because they can loose ${\geq}15%$ of whole-body protein. Conservation of body protein mass during first lactation minimizes wean to estrus interval and increases second litter size (up to 1.2 pigs). The ability to influence litter-size by amino acid nutrition is a new dimension in our understanding. A P2 fat depth below 12 mm at farrow and below 10 mm at wean compromised wean to estrus interval (>2 d) and next litter size (0.5 to 1.5 pigs) in sows. It is now clear that a 'modest' excess of feed during the first 72 h of pregnancy decreases embryo viability so that the potential for an increased litter size at birth is not realized. The capacity for milk production by prolific young sows is 25% higher than the standard used previously (NRC, 1988). First litter females averaged 9.82 kg milk/d for a 21 d lactation. Second and third litter counterparts averaged 10.35 kg/d. Milk production was 95% of peak by 10 d of lactation and sows were in greatest negative energy and lysine balance during the first 6 d. Nearly 45% of the total loss in body protein occurred within the first 6 d, but this could reduced to 30-35% by using a more aggressive feeding strategy after parturition. There appear to be 2 phases in lactation for lysine need (d 2-12 vs 12-21). Feeding to the higher level alleviates the second litter size decline. The lysine requirement for lactation can be predicted with accuracy, but we are not able to predict the second limiting amino acid. Mammary uptake of valine relative to lysine and recent work with practical diets suggest that the recent NRC (1998) pattern is realistic and that threonine and valine could be co-limiting for corn-soy diets for prolific sows nursing 10-11 pigs. Empirical studies are needed to refine the ideal pattern so that synthetic lysine can be used with more confidence. Milk fat output for the elite sow is extraordinary and poses an unnecessarily high energetic cost. Methods that reduce mammary fat synthesis will benefit the sow and may enhance piglet growth.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권5호
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• pp.332-336
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• 2001

When parental Chinese hamster ovary (CHO) cell clones that are capable of producing thrombopoietin (TPO) were subjected to high methotrexate (MTX) concentrations, clonal variations in cell growth were apparent. In the clones that had no significant enhancement in specific TPO productivity (q$\_$Tpo/)when a higher level of MTX was administered, their growth was not depressed significantly nor their cell size changed significantly. On the other hand, those clones that showed a significant-enhancement in q$\_$Tpo/ at higher a MTX dosage, cell growth was depressed initially but recovered during successive sub-cultures. Furthermore, their cell size increased, which suggested that changes in cell size may be indicative of an enhanced q$\_$Tpo/. When the enhancement of the q$\_$Tpo/ of 9 clones after a high MTX dosage was plotted against the extent of the increase of their size, there was a linear correlation (γ$^2$=0.80, p<0.001, ANOVA), which suggested that an enhancement of q$\_$Tpo/ after high MTX administration can be measured by the increase in their cell size. Taken together, our data demonstrate that the selection of amplified CHO cell clones with enhanced q$\_$Tpo/ can be done upon their increased size and growth pattern. This facilitates the development of highly productive recombinant CHO cell lines.

• 한국산학기술학회논문지
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• 제14권5호
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• pp.2443-2448
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• 2013

본 논문에서는 공통 결함접지구조(common defected ground structure, CDGS)를 이용하여 설계한 초고주파 발진기에 대하여 기술한다. 먼저 일반적인 스터브 공진기를 사용하여 발진기를 설계하고, 이를 종래처럼 DGS를 삽입하여 소형화하는 방법을 이용하였다. 최종적으로 DGS 공진기 부분을 반으로 접은 공통 DGS 구조를 이용하여 크기를 대폭 줄인 발진기를 설계하였다. 종래의 DGS를 이용한 경우보다 더욱 소형화된 회로를 얻기 위하여 공통 DGS 구조를 삽입하였다. 공통 DGS 구조를 이용하기 위하여 접혀진 신호선로는 3차원적인 신호선 비어홀(signal via-hole)로 서로 연결된다. 한 설계예로 2.1GHz대에서 소신호 트랜지스터와 공통 DGS 구조를 이용하여 소형화한 발진기를 설계하였다. 설계한 발진기는 표준형 회로에 비하여 11mm만큼 감소한 크기를 가졌다. 제작한 회로를 실제로 측정한 결과 6.7dBm의 출력과 -133dBc/Hz@1MHz의 위상잡음 특성을 얻었다. 출력의 크기는 소형화 이전과 유사한데, 이로써 제안한 발진기 구조의 타당성이 검증된다.