• Title/Summary/Keyword: 실속

Search Result 200, Processing Time 0.022 seconds

Aerodynamic Load Analysis of a Floating Offshore Wind Turbine Considering Platform Periodic Motion (플랫폼의 주기 운동을 고려한 부유식 해상 풍력터빈의 공력 성능 해석)

  • Kim, Youngjin;Yu, Dong Ok;Kwon, Oh Joon
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.46 no.5
    • /
    • pp.368-375
    • /
    • 2018
  • In the present study, aerodynamic load analysis for a floating off-shore wind turbine was conducted to examine the effect of periodic platform motion in the direction of 6-DOF on rotor aerodynamic performance. Blade-element momentum method(BEM) was used for a numerical simulation, the unsteady airload effects due to the flow separation and the shed wake were considered by adopting a dynamic stall model based on the indicial response method. Rotor induced downwash was estimated using the momentum theory, coupled with empirical corrections for the turbulent wake states. The periodic platform motions including the translational motion in the heave, sway and surge directions and the rotational motion in the roll, pitch and yaw directions were considered, and each platform motion was applied as a sinusoidal function. For the numerical simulation, NREL 5MW reference wind turbine was used as the target wind turbine. The results showed that among the translation modes, the surge motion has the largest influence on changing the rotor airloads, while the effect of pitch motion is predominant for the rotations.

Analysis of Aircraft Upset through TEM and Improvement of UPRT (항공기 비정상 자세 사고의 TEM 분류 및 UPRT 향상에 관한 연구)

  • Choi, Jin-Kook;Jeon, Seung-Joon
    • The Journal of the Korea Contents Association
    • /
    • v.19 no.11
    • /
    • pp.365-374
    • /
    • 2019
  • Loss of Control in Flight(LOC-I) due to aircraft upset attitude has the highest air accident rate, and International Aviation Institute such as ICAO and FAA recommended flight crew to operate aircraft safely through UPRT(Upset Prevention & Recovery Training) program. ICAO has selected Loss of Control(LOC) as key safety indicator, and recommended to respond using TEM(Threat and Error Management). However there are not much specific treats and errors classified for UPRT programs using real TEM based on evidences. This study intends to consider the importance of UPRT through the introduction of UPRT and accident analysis using TEM. Typical upset accidents were classified to common threats as IFR, inadequate training, Automation surprise, and inexperienced copilots. The common errors were cross-check, speed and altitude deviation, callouts, communication, thrust and stall action fail. The undesired aircraft states were inadequate automation mode, Deviation of speed and vertical, stall, and crash. These suggest areas to improve UPRT.

A Study on the Selection Factors in Credit Cards by the Lifestyle of Elderly Groups (실버층의 라이프스타일에 따른 신용카드 선택요인에 관한 연구)

  • Seo, Kyoung Hwan;Kim, Sook Eung
    • Journal of Service Research and Studies
    • /
    • v.6 no.1
    • /
    • pp.29-50
    • /
    • 2016
  • The purpose of this study is to identify the motivation of using and choosing factors in credit cards. These results indicate that considerate of other people factor may emphasize the convenience and safety in using credit cards, while the leisure factor may prefer the real-worth factor as they know that the more they use, the more benefits they would get. As the personality factor and the fashion factor, we can pay much attention to the advertisements, promotions, card designs, the colors, the characters and the social positions of the card holders and that considerate other people factor may like the low annual fees and the accumulating points, buying items on the installments without paying additional interest, which had offered them cash service and card loan. The authors of this paper has suggested an information by which credit card companies can establish the strategies according to the lifestyle of the elderly in silver business market.

Ultrastructural Study on the Ependymal Cells of the Read-Irradiated Rats (방사선이 뇌실막세포의 미세구조에 미치는 영향)

  • Ahn, E-Tay;Cho, Hwee-Dong;Kim, Jin-Gook;Park, Kyung-Ho;Ko, Jeong-Sik
    • Applied Microscopy
    • /
    • v.29 no.1
    • /
    • pp.11-23
    • /
    • 1999
  • Ultrastructure of the ependymal cells of X-irradiated rats on their head were studied. Rats weighing $200\sim250gm$ were X-irradiated on their head and neck areas. Total exposures were 3,000 rads or 6,000 rads depending on experimental groups. And irradiated rats were sacrificed on 6 hours, 2 days and 6 days following the radiation exposures. Animals were perfused through the heart with 1% glutaraldehyde-1% paraformaldehyde solution, under ether-anesthesia. The tissues from the wall of lateral ventricles were fixed in the 2% osmium tetroxide solution. The results observed with electron microscope were as follow: 1. In 6 hours group, many ependymal cells were swelled, luminal portions of cytoplasms of some cells protruded into the ventricular lumen, and many cilia were lost or irregularly altered. 2. In 2 days group, ependymal cells were swelled more severely and subependymal edema were pronounced. 3. Protruded cytoplasm contained usually basal bodies of cilia, groups of mitochondria, endoplasmic reticula , etc. 4. Following X-irradiations, some protruded masses contained neural elements including the axon terminals with dense core vesicles. Axons and axon terminals were also found in the enlarged intercellular spaces among ependymal cells. From the above results, the heavy irradiation on the head area of the rat induced alteration of the ependymal cells lining the lateral ventricle. Hence the ependymal functions of selective barrier, protective barrier, and metabolic barrier could be altered following X-irradiation on the head.

  • PDF

Characteristics of Noise Emission from Wind Turbine According to Methods of Power Regulation (파워 조절 방법에 따른 풍력 터빈의 방사 소음 특성)

  • Cheong, Cheol-Ung;Cheung, Wan-Sup;Shin, Su-Hyun;Chun, Se-Jong;Choi, Yong-Moon;Jung, Sung-Soo
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.16 no.8 s.113
    • /
    • pp.864-871
    • /
    • 2006
  • In the development of electricity generating wind turbines for wind farm application, only two types have survived as the methods of power regulation; stall regulation and full span pitch control. The main purpose of this paper is to experimentally identify the characteristics of noise emission of wind turbines according to the power regulation types. The sound measurement procedures of IEC 61400-11 are applied to field test and evaluation of noise emission from each of 1.5 MW and 660 kW wind turbines (WT) utilizing the stall regulation and the pitch control for the power regulation, respectively. Apparent sound power level, wind speed dependence, third-octave band levels and tonality are evaluated for both of WTs. It is observed that equivalent continuous sound pressure levels (ECSPL) of the stall control type of WT continue to increase with increasing wind speed whereas those of the pitch control type of WT show less correlation with wind speed. These observed characteristics are believed to be due to the different airflow patterns around the blade between the stall regulation and the pitch control types of WT; the airflow on the suction side of blade in the stall types of WT are separated at the high wind speed. It is also found that the 1.5 MW WT using the stall control emits lower sound power than 660 kW one using the pitch control at wind speeds below 8m/s, whereas sound power of the former becomes higher than that of the latter in the wind speed over 8m/s. This wind-speed dependence of sound power leads to the very different noise omission characteristics of WTs depending on the seasons because the average wind speed in summer is lower than 8m/s whereas that in summer is higher. Based on these experimental observations, it is proposed that, in view of environmental noise regulation, the developer of wind farm should give enough considerations to the choice of power regulation of their WTG based on the weather conditions of potential wind farm locations.

Development of rice(Oryza sativa L.) transformation system to improve callus utilization (캘러스 활용도를 향상시키기 위한 벼(Oryza sativa L.) 형질전환 시스템 구축)

  • Park, Ji-Sun;Moon, Ki-Beom;Ha, Jang-Ho;Jang, Ji-Young;Kim, Mi-Jin;Jeon, Jae-Heung;Park, Sang-Un;Kim, Hyun-Soon
    • Korean Journal of Breeding Science
    • /
    • v.49 no.3
    • /
    • pp.170-179
    • /
    • 2017
  • Plant molecular farming has attracted a lot of attention lately in the field of mass production of industrially valuable materials by extending application of the plant as a kind of factory concept. Among them, protein expression system using rice(Oryza sativa L.) callus is a technology capable of mass culture and industrialization because of a high expression rate of a target protein. This study was carried out to develop an Agrobacterium-mediated transformation system to increase the utilization of rice callus. The transformation efficiency was improved by using the hand when seeds were de-husked for callus induction. Furthermore, we were possible induction of callus from 6 years old seed smoothly. Selection of the callus contained the target gene was required a cultivation period of at least 3 weeks, and the most efficient selection period was after 6 weeks of culture including one passage. This selection was confirmed that the gene was stably inserted into the genomic DNA of the plant cell by the southern blot analysis and progeny test. Such an efficient selection system of rice callus that can be cultured in the long term will be contribute to the industrialization of useful recombinant proteins using rice.

Development of Health Promotion Program through IUHPE - Possibilities of collaboration in East Asia - (IUHPE를 통한 건강 증진 프로그램의 발달-동아시아권의 공동연구의 가능성-)

  • Moriyama, Masaki
    • Proceedings of The Korean Society of Health Promotion Conference
    • /
    • 2004.10a
    • /
    • pp.1-16
    • /
    • 2004
  • This paper considers the possibilities of health promotion from the following perspectives; (1) IUHPE, (2) socio-cultural similarities, (3) action research, and (4) learning from our past. 1. The IUHPE values decentralized activities through regions, and countries such as Japan, Korea, Hong Kong, Taiwan and China belong to NPWP region. Since IUHPE World Conference was held in Japan in 1995, Japan used to occupy more than 60% of NPWP membership. After 2001, membership is increasing rapidly in Chinese speaking sub-region. The transnational collaboration is still in its beginning phase. 2. Confucianism is one of key points. Confucian tradition should not be seen only as obstacles but as advantages to seek a form of health promotion more acceptable in East Asia. 3. Within the new public health framework, people are expected to create and live their health. However, especially in Japan, the tendency of 'lacking of face-to-face explicit interactions' is still common at health-promotion settings as well as academic settings. Therefore, the author tried participatory approaches such as asking WlFY (interactive questions designed for subjects to review their daily life and environment) and as introducing round table interactions. So far, majority of participants welcome new trials. 4. The following social phenomena are comparatively discussed after Japanese invasion and occupation of Korea ended in 1945; ·status of oriental medicine, ·separation of dispensary services, and ·health promotion specialist as a national license. In contrast to Japanese' tendency of maintaining the status quo and postponing of substantial social change, trend toward rapid and dynamic social changes are more commonly observed in Korea. Although all of above possibilities are still in their beginning stages, they are going to offer interesting directions waiting for further challenges and accompanying researches.

  • PDF

A study of the small productional system for 3D digital animations (3차원 디지털애니메이션을 위한 소형제작시스템 연구)

  • Choi, Bek
    • Archives of design research
    • /
    • v.19 no.2 s.64
    • /
    • pp.73-80
    • /
    • 2006
  • The main purpose of this study is to help develop the productional system of the three dimensional digital animation domestically. Many 30 digital animation projects are being developed and finished with foreign computer graphics technology. However, the 3D animation market in Korea is not as good as the ones in other countries. One of the most significant problems is the lack of a program of study in Korea concerning productional systems used to create 3D animation. We previously imported an advanced productional system from the U.S., which was adaptable to big projects, and consequently, expanded the international digital animation market. Now, we need to develop a new production system which is fully adaptable to the Korean market. A non-sequential system of 3D digital animation tailored for small projects is more adaptable to domestic industry than the sequential system known as the 'Pipeline system.' A non-sequential system is good for small productions that are trying to create animation on a limited budget. The workers in this system can learn to make animation fast and effectively. They can also learn how to discuss with the others in order to avoid duplication of action. In contrast, in the Pipeline System, many workers repeat confirmation steps during the process for the same animations. The benefit of the non-sequential system is that the worker's interest and education can speed up production, because he/she can quickly learn every step of the animation process instead of just doing a particular job which does not allow him/her to observe the other steps involved. The 'animatic' step is the most important in the non-sequential system. The final animation is produced from the animatic. It is developed from scratch through to the final product but only after the agreement of all the workers, including a director.

  • PDF

Analysis of Language Message Expression in Beauty Magazine's Cosmetic Ads : Focusing on "Hyang-jang", AMOREPACIFIC's from 1958 to 2018 (화장품광고에 나타난 언어메시지 표현분석 : 1958년~2018년의 아모레퍼시픽 뷰티매거진<향장>을 중심으로)

  • Choi, Eun-Sob
    • Journal of Korea Entertainment Industry Association
    • /
    • v.13 no.7
    • /
    • pp.99-118
    • /
    • 2019
  • This study confirmed the followings based on analysis of language messages in 718 advertisement in , AMOREPACIFIC's beauty magazine, published from 1958 to 2018 by product categories, era, in terms of purchase information, persuasive expression, word type. First, the number of pieces among 1980s to 1990s advertisement were the largest and, in terms of product categories, there were the greatest number of pieces in skincare, makeup and mens products. Second, headline and bodycopy had a different aspect in persuasive expression. "focused on image-making" was mainly used for head lines. Specifically, "situational image" was generally dominant. While the "user image" was higher before 1990's, "brand image" was as recent times. "Informal" was mostly applied for bodycopies, especially, "general information" and "differentiated information" was used the most. It is important to know what kind of information the brand established in each brand should be embodied rather than simply dividing the appeal method into "rational appeal" and "emotional appeal."Third, persuasive expression has different aspects in headlines and body copies. "focused on image-making" was mainly used as headlines. Specifically, "situational image" is dominant. Also, "user image" was high before 1990s but "brand image" got higher in recent times. "Informal" was mostly used as body copies, especially "general information" and "differentiated information" were the most frequently selected. Therefore, it is important to apprehend which information to specify established images by brands, rather than to divide "rational appeals" and "emotional appeals". Lastly, categorizing word type into brand names and headlines, foreign language was the most dominant in brand names and Chinese characters in headline. Remarkably, brand names in native language temporarily high in 70's and 80's, which could be interpreted to be resulted from the government policy promoting native language brands in those times. In addition, foreign language was frequently used in cosmetics and Chinese characters in men's product. It could be explained that colors or seasons in cosmetic products were expressed in foreign language in most case. On the other hand, the inclination of men's product consumers, where they pursue prestige or confidence in Chinese character, was actively reflected to language messages.

A Survey on Breakfast of Commuting Local College Students and Suggestions for Desirable Breakfast Menu (통학 지방대학생의 아침식사 섭취실태와 바람직한 아침식단에 대한 제안)

  • 이혜양
    • The Korean Journal of Food And Nutrition
    • /
    • v.11 no.3
    • /
    • pp.323-328
    • /
    • 1998
  • This study was to investigate regularity of breakfast and food habits of commuting local college students. The regularly breakfast eating rate was found to be 32.9% in man and 26.5% in woman. The mean score of food habits was pretty low, 36.7 out of minimum possible score 12 and maximum 60. The mean score of nutrition attitude was 58.1 out of minimum possible score 18 and maximum 90. This survey showed that skipping breakfast or irregularity of breakfast led to overeating, high fat diet, lot of alcohol and imbalanced diet. It was known that breakfast was the most important among three meals. But having balanced breakfast daily was very difficult according to loss of appetite and busy schedule early in the morning. I suggested carbohydrate food, protein food, and vitamin & mineral food items desirable for nutritionally balanced, easily digestible, tasteful, quick and easily cooking breakfast menu. It was recommended to choose on item out of each of three food categories considering calory(1/3 of daily recommended calory intake for breakfast).

  • PDF