• 대한기계학회논문집A
• /
• 제38권3호
• /
• pp.309-314
• /
• 2014

기계나 토목 구조물의 형상은 일반적으로 전통적인 방법들을 이용하여 얻었다. 예를 들면 전력송전탑이나 해상풍력 하부구조물 이외의 다른 구조물들도 조직적으로 만든다. 한편 컴퓨터 그래픽의 급속한 성장으로 인해, 진화된 구조해석 및 최적설계기법들을 이용하고 있다. 본 논문에서는 해상 풍력 터빈을 위한 자켓 구조물의 구조형상을 위상최적화 기법을 통하여 연구하였다. 이번 연구는 실제작동하중상태로 시뮬레이션을 위하여 다 하중으로 종속시켰으며, 최적화 목적 함수는 주어진 경계조건아래 컴플라이언스로 정의하였다. 최적화는 고유진동수와 체적을 구속함수로 사용하였으며, 1 단계 모델의 결과는 2 단계 구조를 위한 외형을 빠르게 볼 수 있도록 한다. 그 결과로 사각뿔대의 3D 모델은 위상최적화를 통하여 개발하였다.

• 기술경영경제학회:학술대회논문집
• /
• 기술경영경제학회 1997년도 제11회 하계학술발표회 논문집
• /
• pp.224-243
• /
• 1997

The study examines the similarities of competitive strategy between fashion industry and high-tech industry through a case study of a Japanese maker. From the study, some implications are drawn for the Korean fashion industry. It is hoped that this, will help towards establishing a suitable competitive strategy for firms in this industry. In the fashion industry, the product life cycle is so short as to prompt a new product obsolete too quickly, and the extent of product differentiation is remarkably extensive compared to any other industry. Generally speaking, firms in this industry focus more of their resources on product development and marketing rattler than on production and they attempt to maneuver the speed when they are required to enhance their competitive edge. This is enabled through being, as one might expect, information- and technology- intensive as are high-tech industries. In this sense, that of the competitive strategy of a firm in fashion industry to be similar to high-tech industry. The Japanese firm Y has transformed itself a leading firm in fashion uniform segment. The firm could achieve this status by integrating each function needed for creating customer*s value, that is, product development, production and marketing within one Quick Response System. For this purpose, Y introduced a bundle of high-tech communication systems such as SPD, SDS, ATOM, NICS and so on. In this sense it can be said that Y was aware of what sort of competitive strategy was required in the industry. Implications for Korean firms is that, first, the magnitude of understanding the industry specific factors in establishing competitive strategy in the fashion industry, are speed, flexibility and systematic integration supported by high technology which are characteristic of high-tech industries. Secondly, as can be seen in the fact that Y emphasized logistics in its technological transformation, the significance of logistics control is a key to manipulating speed and flexibility in the industry. To sum up, those who have insight into above findings will be likely to keep their competitiveness in the industry not only in the Korean market but also in global market in the near future.

• 한국의류학회지
• /
• 제40권5호
• /
• pp.910-920
• /
• 2016

This study is to understand the problems of current police raincoats for professional policemen and conscripted policemen. Interviews and a survey were completed to investigate the wearing conditions of current police raincoats. The questionnaire was composed of questions on current wearing conditions of raincoat, motional adaptability, dimensional compatibility, design suitability and demographic information on the research target. The results indicated that the wearing frequency of raincoats had significant difference according to duty and age range. The main reason for the low wearing frequency was the uncomfortableness of working while wearing the raincoat, followed by the inconvenience of managing the raincoat after use and feeling hot while wearing the raincoat. The three most important factors when wearing a raincoat was pleasantness, activity capability and the functionality of the fabric. The satisfaction on body parts during motions tended to be evaluated lower as the raincoat size increased. The results of the dissatisfaction factors indicated that the raincoat hood had the most problems. There was inconvenience when using the equipment belt because officers have to wear their belts inside the raincoat. In regards to the fabric satisfaction level, respondents were less satisfied with ventilation, hygroscopicity, and drying time. Therefor it appeared that the current raincoat had problems due a lack of functionality in regards to ventilation, hygroscopicity, and quick drying; in addition, the satisfaction on motional adaptability had a significant difference according to raincoat size.

• 조명전기설비학회논문지
• /
• 제14권3호
• /
• pp.29-37
• /
• 2000

본 논문에서는 TMS320C32 DSP를 사용하여 저속에서 구동되는 반송용 펀측식 전행 유도전동기의 슬립 각 주파수에 의한 벡터제어를 이용하여 추력제어하였다. 먼저, 반송용 편촉식 선형 유도전동기를 설계 및 제작하고, 이를 해석하였다. 저속에서 제풍의 운반시에 안정성있은 구동올 위해서 벡터제어에 의한 추력제어를 하였고, 정위치 제어를 하기 워해서 Ziegles- Nichols법을 이용하여 PiD제어기를 설계하였다. 저속에셔의 종량부하흘 갖는 반송용 선형기기에서 PID제어기에 추력제어가 가능한 벡터제어기법을 부가한 결과는 제품외 운반시에 안정성있는 구동을 하였으며, 정위치제어를 위한빠른 응답특쟁 및 soft start/stop을 이루었으며, 부하 변동시에도 제동시에 정위치제어를 위한 빠른 응탑 특성의 결과를 얻었다.

• 아시안잔디학회지
• /
• 제25권1호
• /
• pp.69-72
• /
• 2011

토양입단화는 토양의 물리적 화학적 그리고 생물학적인 변화를 일으키는 활발한 과정이다. 토양입단화를 통해서 생성된 토양공극은 토양에서 공기와 물의 순환을 증가시키는 역할을 하게 된다. 유기중합물이 토양입단 안정화에 대한 긍정적인 역할은 많은 연구결과에서 보고가 된 바 있다. 본 실험의 목적은 유기중합물이 토양입단화와 페레니얼 라이그래스의 성장에 미치는 영향에 대해서 알아보기 위해서 수행되었다. 유기중합물의 세가지 농도가 적용이 되었으며 실험을 위해 두가지 토양이 사용이 되었다. 첫번째 토양으로 4.0%의 유기물이 함유된 양토가 건조된 후 사용이 되었으며 두번째 토양으로 점토가 사용이 되었다. 유기중합물 처리에 따른 페레니얼 라이그래스의 색, 품질, 성장에 미치는 영향은 나타나지 않았다. 그러나 유기중합물이 토양입단화에는 토양의 종류에 따라 영향이 있는 것으로 나타났다. 본 실험의 결과의 구체적인 실증을 위해서 필드 실험이 필요한 것으로 판단이 된다.

• 한국항행학회논문지
• /
• 제21권6호
• /
• pp.633-637
• /
• 2017

항공기와 항공 네트워크에 대한 사이버 공격은 일반적으로 지상 산업에서 흔히 볼 수 있는 사이버 공격과 크게 다르지 않다. 항공 교통 인프라스트럭처(infrastructure)는 항공 교통 자원 확보를 위해 디지털 기반 구조로 전환되고 있다. 다양한 종류의 통신 환경과 정보 통신, 항법, 감시 및 기내 엔터테인먼트 시스템이 사이버 테러 위협에 노출될 위험을 가중시키고 있다. 또한 무인항공기의 출현은 사이버 테러에 의해 통제될 수 없는 위험을 내포하고 있다. 차세대 데이터 네트워크 시스템 환경에서 항공기 시스템 및 항공 기반의 인프라스트럭처에 대한 사이버 위협의 취약점을 인식하고 항공 선진국의 사이버 보안 표준과 대응 전략을 분석했다. 그리고 국내 항공 환경에서 고려해야 할 사이버 보안 정책에 대한 포괄적인 방안을 논의하고, 보안 환경에 대한 개념과 신속한 대응 전략 수립 등을 논의하였다.

• 대한기관식도과학회지
• /
• 제9권1호
• /
• pp.60-66
• /
• 2003

Although there is a wide range of diseases caused by gastric acid reflux and the number of cases is on the rise, it is difficult for the laryngologist to make the correct diagnosis. The treatment for laryngopharyngeal reflux can be grouped into 3 categories - changes in lifestyle, medication, and surgery. The medication used to treat laryngopharyngeal reflux are prokinetic agents and acid supressive agents such as antacids, H2 blockers, and PPIs(Proton pump inhibitor). Rabeprazole sodium($Pariet^{\circledR}$) is a newly developed agent belonging to the PPI group, but in contrast with the existing drugs such as omeprazole, lansoprazole, pantoprazole, has a low dependency on CYP2C19 during the metabolic cycle. Thus, it is known to have a quick but fixed antiacid effect and less individual differences. We analyzed 2166 patients from 32 hospitals who were prescribed $Pariet^{\circledR}$ from May, 2001 to April, 2002. The patients were divided into 4 groups according to the duration of treatment - Group 1: 1-14 days, Group 2: 15-28 days, group 3: 29-56 days, Group 4: more than 56 days. The cases were then analyzed for improvement of 8 symptoms(heart bum, regurgitation, chronic cough, hoarseness, globus sensation, chronic throat clearing, sore throat, and dysphagia), improvement on laryngoscope, usefulness to the doctor, and complication development. Of the total of 2116 patients, 1627(75.1%) cases showed at least 50% improvement of symptoms and the amount of improvement increased according to the duration of medical treatment. Most of the patients showed objective improvement on the laryngoscope, with 32.9% showing significant improvement and 38.7% showing moderate improvement. 37.6% of the doctors questioned replied that $Pariet^{\circledR}$ was very useful and 50.3% said it was useful, showing that most were satisfied with the treatment results. The complications known to develop after taking PPI are headache, nausea, diarrhea, abdominal pain, constipation, dizziness, fatigue, and of these, only a small percentage of the patients complained of mild headache. $Pariet^{\circledR}$ has shown to be a relatively safe and effective drug for the treatment of laryngopharyngeal reflux.

• 농업과학연구
• /
• 제41권2호
• /
• pp.75-83
• /
• 2014

Recently, a quick drop of air temperature in plastic film houses by adverse weather conditions leads to the occurrence of low temperature damages to growing crops. Chilling injury, defined as a variety of growth restriction occurring below the optimal temperature, is one of environmental factors strongly affecting crop growth and yield. Low temperature causes the restricted evapotranspiration, reduced mineral uptake (P > K > $NO_3{^-}$), and an increase in electrolyte leakage such as K. Despite being different with plant species, an accumulation of soluble carbohydrates such as glucose, fructose, sucrose and starch under chilling condition is well known. A variety of environmental stresses are known to cause oxidative damage to plants either directly or indirectly by triggering an increased level of production of reactive oxygen species (ROS), and, to combat the oxidative damage, plants have the antioxidant defense systems comprising of enzymes, SOD, POD, CAT, GPX and APX, and non-enzymes, ascorbate, gluthathione, ${\alpha}$-tocopherol, phenolic compounds, carotenoid and flavonoids. The aim of this review is to provide basic information to build chilling-indicators and optimal nutrition management under adverse temperature conditions as broadly considering mineral uptake, carbohydrate metabolism and antioxidative defense system.

• 융합보안논문지
• /
• 제15권2호
• /
• pp.11-17
• /
• 2015

정보화 진흥원의 정보격차실태 보고서에 의하면 최신 IT 기술은 정보를 가진 사람과 가지지 못한 사람간의 삶의 질의 격차를 증가시키는 사회적 문제로 대두되고 있다. 따라서 본 논문에서는 정보 소외 계층 중에서 시각장애인을 위한 점자키보드 시스템 기술을 제안하여 정보 격차 해소에 도움이 되고자 한다. 시각 장애인들의 휴대사용과 편의성, 빠른 텍스트 입력에 초점을 맞추어 무선 데이터 전송 기술 기반으로 설계를 하였으며 텍스트 입력 실험에서는 한글, 영어, 숫자 모두 잘 표현이 되었고 속도는 분당 22타가 나왔다. 특히 문자를 인식하여 음성으로 출력해 주는 기능을 통해 사용자가 정확한 문자입력이 가능하도록 설계하였으며, 전화, 알람, 카카오톡, 인터넷, 음악, 문자도 사용하는데 지장이 없었다. 제안한 기술은 스마트폰의 사용자 확대를 통하여 정보 격차 해소에 크게 기여할 것으로 사료된다.

• 한국초전도ㆍ저온공학회논문지
• /
• 제22권2호
• /
• pp.7-11
• /
• 2020

When rivers and lakes are contaminated with numerous contaminants, usually the contaminants are finally deposited on the sediments of the waterbody. Many clean up technologies have been developed for the contaminated sediments. Among several technologies dredging is one of the best methods because dredging removes all the contaminated sediments from the water and the contaminated sediments can be completely treated with physical and chemical methods. However the most worried phenomenon is suspension of fine particles during the dredging process. The suspended particle can release contaminants into water and resulted in spread of the contaminants and the increase of risk due to the resuspension of the precipitated contaminants such as heavy metals and toxic organic compounds. Therefore the success of the dredging process depends on the prevention of resuspension of fine particles. Advanced dredging processes employ pumping the sediment with water onto a ship and release the turbid water pumped with sediment into waterbody after collection of sediment solids. Before release of the turbid water into lake or river, just a few minutes allowed to precipitate the suspended particle due to the limited area on a dredging ship. However the fine particle cannot be removed by the gravitational settling over a few minutes. Environmental technology such as coagulation and precipitation could be applied for the settling of fine particles. However, the process needs coagulants and big settling tanks. For the quick settling of the fine particles suspended during dredging process magnetic separation has been tested in current study. Magnetic force increased the settling velocity and the increased settling process can reduce the volume of settling tank usually located in a ship for dredging. The magnetic assisted settling also decreased the heavy metal release through the turbid water by precipitating highly contaminated particles with magnetic force.