• 기술사
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• 제38권1호
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• pp.52-54
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• 2005

Korean metropolises are choked by lack of green space to attain the limit of horizontal expansion. The alternative plan is trying total expansion that the green zone and road are made from the rest site by high-rise buildings. And high-rise building can solve indiscriminate development to attain the limit situation. The building of landmark can be the image of the nation and the pride of the citizen. The relaxing the height restriction of government can be whole nation's interests. Appearing high-rise building in overpopulated city is the subject of a generation and this trend cannot be avoided.

• 정보저장시스템학회논문집
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• 제1권1호
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• pp.67-72
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• 2005

This study proposes a design methodology to determine the optimum configurations of the optical flying head (OFH) for near-field recording systems. Since the OFH requires stricter static and dynamic characteristics of slider air-bearings within an optical tilt tolerance over the entire recording band, an optimum design to keep the focusing and tracking ability stable is essential. The desired flying characteristics considered in this study are to minimize the variation in flying height between the SIL and the disk from a target value, satisfying the restriction of the minimum flying height, to keep the pitch and roll angles within an optical tilt tolerance, and to ensure a higher air-bearing stiffness. Simulation results demonstrate the effectiveness of the proposed design methodology by showing that the static and dynamic flying characteristics of the optimally designed OFH are enhanced in comparison with those of the initial. The gap between the SIL and the disk can be kept at less than 100 nm even if the optical tilt tolerance of the SIL is considered.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.422-429
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• 1997

Thermal stress induced by hydration heat may produce cracks in mass concrete structure, which can result in structural problems as well as bad appearance. To minimize crack occurrence in massive structural, thus, the study put an emphasis on the determination of optimized lift height and block size. In the parametric study different sizes and lift heights were used to measure the magnitudes of hydration heat and thermal stresses for 3 different types of concrete fabricated with 1 pure cement and 2 blended Portland cements. As a result of analysis. it was found that magnitude of hydration heat and the occurrence of thermal cracks depend on the restriction conditions and material characteristics, especially adiabatic material parameters. It was also found that optimized lift height and block size can be determined from an appropriate combination of the degree of inner and outer structural restrictions.

• 한국공작기계학회논문집
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• 제16권2호
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• pp.100-105
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• 2007

Electro-rheological(ER) fluid and valve are fabricated and evaluated experimentally in its durability to utilize the hydraulic control systems for long term operation. The two-ports ER valve used in the experiment consist of twelve parallel multi-layer electrodes and provide a restriction to the passage of ER fluid because of the viscous pressure drop and a component induced by the electric field. The durability test of ER valve are performed by measuring the surface roughness of electrodes with variation of an electric field strength and test time(1000 or 1800min.). Also, the shear stress and shear rate are measured to evaluate the durability of ER fluid as function of time. After durability test, ER shear stress increases approximately proportional to the shear rate with applied electric field intensity, In the ER valve, the center line average height roughness(Ra) of copper electrode increases about 1.56 times and ten-point median height roughness(Rz) increases about 2.2 times after the durability test. An understanding of these durability is essential to predicting the service life of ER fluid and valves.

• Clinical and Experimental Pediatrics
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• 제59권4호
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• pp.165-173
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• 2016

Purpose: To identify the effects of modified parenteral nutrition (PN) and enteral nutrition (EN) regimens on the growth of very low birth weight (VLBW) infants. Methods: The study included VLBW infants weighing <1,500 g, admitted to Chungnam National University Hospital between October 2010 and April 2014, who were alive at the time of discharge. Subjects were divided according to 3 periods: period 1 (n=37); prior to the PN and EN regimen being modified, period 2 (n=50); following the PN-only regimen modification, period 3 (n=37); following both PN and EN regimen modification. The modified PN regimen provided 3 g/kg/day of protein and 1 g/kg/day of lipid on the first day of life. The modified EN regimen provided 3.5-4.5 g/kg/day of protein and 150 kcal/kg/day of energy. We investigated growth rate, anthropometric measurements at 40 weeks postconceptional age (PCA) and the incidence of extrauterine growth restriction (EUGR) at 40 weeks PCA. Results: Across the 3 periods, clinical characteristics, including gestational age, anthropometric measurements at birth, multiple births, sex, Apgar score, surfactant use and PDA treatment, were similar. Growth rates for weight and height, from time of full enteral feeding to 40 weeks PCA, were higher in period 3. Anthropometric measurements at 40 weeks PCA were greatest in period 3. Incidence of weight, height and head circumference EUGR at 40 weeks PCA decreased in period 3. Conclusion: Beginning PN earlier, with a greater supply of protein and energy during PN and EN, is advantageous for postnatal growth in VLBW infants.

• 한국항공운항학회지
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• 제30권3호
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• pp.28-37
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• 2022

Obstacle Limitation Surface (OLS) is conceptual surface establishing the airspace around aerodromes to be maintained from obstacles to ensure safe aircraft operations. Despite advances in the technologies for aircraft, navigation systems and the development of new flight procedures, the criteria defining OLS have not been amended since its initial establishment, resulting in the overestimation of areas for height restriction. As there were requests to examine OLS at the 12th Air Navigation Conference and the 38th ICAO Assembly, the research on the OLS revision began in earnest and ICAO has proposed Obstacle Free Surface (OFS) and Obstacle Evaluation Surface (OES) as an alternative of the existing OLS. OFS is surfaces where obstacles shall not be permitted, and OES is ones where obstacles be evaluated with an aeronautical study and could be permitted under some conditions. The purpose of this study is to preemptively assess the efficiency and safety of OFS and OES by applying them to the second runway (15L/33R) of Incheon International Airport. The results show that OFS and OES are capable of serving the instrument flight procedure safely with a smaller obstacle clearance area compared to the existing OLS.

• 정신신체의학
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• 제5권2호
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• pp.168-175
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• 1997

본 연구에서는 부모의 체질량 지수로 알아보는 비만의 가족력, 출생시 체중, 모유 또는 분유 수유, 어린이의 식사습관 및 생활 습관, 부모의 학력 부모의 식이제한 태도 등의 변수들과 아동의 비만과의 상관관계를 검토하여 보았다. 1) 전체 대상 아동 110명중 20.1%인 23명이 OBI가 20%이상인 비만아였다. 두 군에서 평균체중과 OBI는 유의한 차이를 나타내었고(p<0.01), 남아에서 유의하게 비만이 많았으며(p<0.05), 출생시 체중이나 수유의 종류 및 출생 순위등은 유의한 차이가 없었다. 2) 식사 및 생활 습관을 비교해 보면, 비만아에서 음식 먹는 속도가 빠른 경우가 유의하게 많았다(p<0.01) 먹고 싶은 충동을 견디기 어렵다는 경우, 불규칙한 식사, 인스턴트 식품이나 패스트 푸드를 좋아한다는 답변, 간식을 많이 한다, 기름진 음식을 좋아한다는 답변 등은 두군간에 유의한 차이가 없었다. 텔레비젼 시청이나 전자오락을 좋아한다는 답변도 두군간에 차이가 없었다. 3) 비만군에서 아버지의 연령 (p<0.05) 및 교육수준(p<0.05)이 유의하게 높았으며, 부모의 BMI는 두군간에 유의한 차이가 없었다. 4) 비만아동의 어머니에서 인지적 제한 요소인 factor 1과 탈억제 요소인 factor 2가 유의하게 높았으며(p<0.05). 공복감 요소인 factor 3은 두군간에 유의한 차이를 보이지 않았다. 어머니의 교육수준과 TFEQ의 factor 1은 상관관계를 보였으며(r=0.39, p<0.05), factor 1(r=0.38, p<0.05)과 factor 2의 점수가 높을수록 아동의 비만도는 증가하였다(r=0.34, p<0.05). 5) 만 5세 아동의 비만은 부모의 체질량 지수와 같은 유전적 요인보다는 아동 자신의 식사 습관이나 어머니의 식이제한 태도에 더 많은 영향을 받는다고 볼 수 있다.

• 대한지역사회영양학회지
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• 제17권3호
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• pp.271-279
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• 2012

The prevalence of atopic dermatitis (AD) has increased recently all over the world. Several studies worldwide reported growth retardation associated with AD, but few studies were reported in Korea. Therefore, the objective of this study was to identity the differences in growth and nutrient intakes between Korean children with and without AD. The participants were 71 AD children and age, gender-matched 81 control children aged 10 to 36 months. Demographic information was gathered by questionnaires. Height and weight were measured at clinic and health centers. Height and weight for age, and weight for height were converted as deviation in Z scores using World Health Organization Standard. A 24 hour dietary recall method was performed to estimate nutrient intakes. A higher percentage of AD children had insufficient energy and intakes of calcium, phosphorus, iron, zinc and vitamin B2, defined as intakes lower than 75% of the Dietary Reference Intakes for Korean, compared to the control group (P < 0.001, P < 0.001, P = 0.003, P = 0.001, P = 0.014, P = 0.001, respectively). The percentages of children with height and weight for age Z score below than-1 (stunted) were significantly higher in the AD group (P < 0.001 and P < 0.001, respectively). Multiple food restriction, defined as ${\geq}$ 3 food elimination, was associated with insufficient energy and intakes of calcium, phosphorus, iron, zinc, vitamins A and B2. In conclusion, children with AD need regular nutrient assessment and education about alternative food choices to avoid r food elimination in order to prevent growth retardation or inadequate nutrient intakes. Further longitudinal studies for growth and nutrient intakes should be performed to understand the patterns of growth in children with AD.

• 항공우주정책ㆍ법학회지
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• 제35권2호
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• pp.225-246
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• 2020

공항고도제한 완화문제는 단지 항공 기술적인 문제보다 항공기와 관제기술의 급속한 발달을 따라잡지 못하는 Out-dated 된 정책을 Up-dated 시키는 것이라고 본다. 무엇보다 중요한 것은 국민들이 알지 못하는 '비행안전'만 외칠 것이 아니라, 어떻게 하면 지금이라도 국민의 재산권 보장을 위하여 할 수 있는 일이 무엇인가를 심사숙고하고 수행하여야 한다. 공항주변 건축고도제한 완화에 대하여, 국토교통부는 2019년 4월 ICAO 장애물제한표면 TF 검토 후 2026년부터 각 체약국에 적용하는 향후 일정을 마련하겠다고 발표하였다. 그러나, 김포국제공항 인근의 재개발·재건축 대상인 국민들은 국토교통부가 현장 상황을 제대로 파악하지 못하는 정책이라고 보고 있다. 국제민간항공의 UN의 특별기구인 ICAO는 부속서 14, 4.2.4에서 항공안전에 절대적으로 확보가 필요한 진입표면을 제외한 수평표면(45m)은 각 체약국이 항공학적 검토(Aeronautical Study)를 해서 비행안전에 지장이 없으면 완화해주라고 권고하고 있다. 우리나라 정부는 이 권고사항을 따르지 않았고, 미국 등 여러나라는 이를 따라서 이미 국민의 재산권 확보에 크게 이바지하여 왔다. 미국의 연방항공청은 최근 3개월(2019. 7. 15∽10. 14.)간 항공학적 검토를 적용하여 공항고도제한완화를 한 사례들은 14,706건에 이른다. 또한, 일본과 대만은 도심에 있는 비행장 주변의 공역을 재설계하여 국민의 재산권을 보장하고 있다. 국토교통부는 지금이라도 ICAO 체약국으로서, ICAO 부속서 14 (vol. 1. 비행장설계 및 운용 4-2-4) 4.2.4. 권고사항을 미국 등과 같이 따라야 하며, 2026년 ICAO TF의 구체적인 안이 나오기 전에 비행안전구역의 수평표면 (45m)에 대하여 먼저 항공학적 검토를 하여 국민의 재산권을 적극적으로 보장하여야 한다.

• 한국유기농업학회지
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• 제21권4호
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• pp.737-752
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• 2013

This study was conducted to evaluate the allelopathic effect of aqueous extract of Ganghwa domestic mugwort (Artemisia spp.) on vegetables and its related allelo-chemicals. When the receptor vegetables, such as Chinese cabbage, lettuce, and red radish, were treated with aqueous extract obtained from Sajabalssuk (A. $sp^*I$), Ssajuarissuk (A. $sp^*II$) or Ssajarissuk (A. $sp^*III$), their germination rate, leaf number, plant height, and root length were restricted with increasing concentration of aqueous extract. Allelopathic effect was the highest in radish, than lettuce and Chinese cabbage in order. The growth of topplant were more inhibited then root growth observing in restriction of plant height, root length, and chlorophyll contents. The plant height, the root length of red radish were 53.3 and 61.2% and their fresh weights were 19.8 and 26.4% compared to those of controls, respectively. A. $sp^*III$ showed the highest allelopathic effect among the donor plants. In HPLC analysis, 7 phenol compounds were identified in A. $sp^*I$ and A. $sp^*II$, and, in A. $sp^*III$, and hydroxybenzoic acid and phenylacetic acid were further identified as allelochemicals. It is considered that their plant growths were variously inhibited by the amounts and types of allelochemicals in aqueous extracts. To increase the productivity of farm land after cultivation of mugwort, these results can be useful to select the following field crops.