• Title/Summary/Keyword: 인증규격

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Basic Characteristic Verification of High-damping Laminated Solar Panel with Viscoelastic Adhesive Tape for 6U CubeSat Applications (점탄성 테이프를 적용한 6U 큐브위성용 고댐핑 적층형 태양전지판의 기본 특성 검증)

  • Kim, Su-Hyeon;Kim, Hongrae;Oh, Hyun-Ung
    • Journal of Aerospace System Engineering
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    • v.15 no.1
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    • pp.86-94
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    • 2021
  • PCB-based deployable solar panel is mainly used for CubeSat due to its lightweight and easy of electrical connection. However, as the size of solar panel increases, there is a limit to ensuring the structural safety of solar cells due to excessive dynamic displacement under launch vibration environment. In previous mechanical designs, for the minimization of dynamic deflection, panel stiffness is increased by applying additional stiffeners made of various materials such as aluminum or composite. However, it could have disadvantages for CubeSat design requirements due to limited mass and volumes. In this study, a high-damping 6U solar panel was proposed. It had superior damping characteristic with a multi-layered stiffener laminated with viscoelastic acrylic tapes. Basic characteristics of this solar panel were measured through free-vibration tests. Design effectiveness of the solar panel was validated through qualification-level launch vibration test. Based on test results, vibration characteristics of a typical PCB solar panel and the high-damping laminated solar panel were predicted and a comparative analysis was performed.

A Study on the Development Trends of Polymer Electrolyte Membrane Fuel Cells and Application to Ships (국내외 PEMFC 개발 동향 및 선박 적용에 관한 고찰)

  • Lee, Chang-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.4
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    • pp.657-666
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    • 2022
  • The International Maritime Organization(IMO) recommends the active implementation of national policies on technological development and energy efficiency to reduce Green House Gas (GHG) in the international shipping sector. Such IMO environmental regulation policies have a great impact on the entire shipping sector and are also a heavy burden on ship's owners. The most reasonable way to curb GHG emissions from ships comes down to the development of zero-emission ships. In other words, the development of a fuel cell ship (FCS) driven by an eco-friendly fuel is an alternative that can escape the IMO regulations. Countries in Asia, Northern America, and Europe independently develop and produce PEMFC, and are pursuing international standardization by acquiring approval in principle from an internationally accredited registration authority. Currently, there are three types of fuel cells (FC) that are recommended for ships: a Polymer Electrolyte Membrane Fuel Cell (PEMFC), a Molten Carbonate Fuel Cell (MCFC), and a Solid Oxide Fuel Cell (SOFC). In this study, PEMFC, which is expected to grow continuously in the global FC market, was analyzed domestic and international development trends, specifications, performance, and empirical cases applied to ships. In addition, when applying PEMFC to ships, it was intended to suggest matters to be considered and the development direction.

Indonesian Halal Food Consumers' Perception, Attitude and Use of Ginseng and Red Ginseng Products (인도네시아 할랄식품 소비자의 인삼·홍삼제품에 대한 인식과 태도 및 이용 실태)

  • Park, Soojin
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.11
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    • pp.1-15
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    • 2017
  • Understanding muslim consumers' needs and behaviour is an essential process for strategic product development in the Halal food market. For our study on Indonesian consumers of Halal food, we conduct a survey of 200 Muslims residing in Indonesia on awareness of ginseng (G) and red ginseng (RG) products, eating experience, like or dislike reasons, cognitive level on the efficacy of G and RG products, purchase behaviors, satisfaction and repurchase intention through a web-based questionnaire methodology. This study reveals that 58 % and 51% of the participants indicate an awareness of G and RG products. In particular, awareness amongst medium- and high-income male consumers in their 20s and 30s is relatively high. This group of participants is also more likely to consume eat G and RG products for health promotion, refreshment, and disease prevention, and positively evaluated product efficacy. They are also aware of the efficacy claims of these products with regard to enhancement of immunity, fatigue, and stamina. While Indonesian Muslim consumers express satisfaction with the health claims, packaging specifications, and design of the products, they are dissatisfied with product types, price, taste, and aroma. The results also found that participants would recommend G and RG products to acquaintances, and are willing to purchase them in the future. Therefore, the segmentation of Halal-certified G and RG products for Muslim consumers and analysis on their product needs could be advantageous for strategic product development.

Comparative Analysis on the Perceptions for Food Additives Between Elementary School Teachers and Nutrition Teachers (식품첨가물에 대한 초등교사와 영양교사의 인식 비교)

  • Kim, Jeong-Weon;Lee, Eun-Ju
    • Journal of Food Hygiene and Safety
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    • v.31 no.2
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    • pp.74-84
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    • 2016
  • Literacy on food additives of elementary school teachers (ET) and nutrition teachers (NT) could be influential factor on safe dietary education for school children. Therefore, the perceptions and information needs on food additives were surveyed from 351 elementary school teachers and nutrition teachers in metropolitan area of Korea, and the basic data for the promotion of risk communication on food additives among them were obtained. Compared to ET who consider 'taste' (39.1%) as the most important factor while purchasing food, NT considered 'safety' (68.1%) first (p < 0.001). Among the food labelling items, the level of understanding on food additives was the lowest both in ET (3.53) and NT (4.17), and NT showed better levels of understanding overall on food labels. Both ET and NT regarded hazardous factors of food as environmental pollutants, foodborne pathogens, and food additives in order, and tended to select 'no additives' or 'no artificial color' products while purchasing processed food. Although NT answered that they know all food additives had been passed the evaluation of safety and effectiveness tests (100%) and have standards of use (81.9%), majority of them (87.5%) believed the consumption of food additives are harmful on human health. ET (75.2%) also regarded food additives as dangerous materials. Above results suggested the necessity of proper and enough risk communication for both ET and NT. Both ET and NT wanted to have information on the safety or hazard of food additives. Most preferred media to get the information on food additives was TV (3.80) among ET and lecture (3.65) among NT. ET and NT trusted hospital, research institution/universities or the personnels working in these institutions as the provider of information on food additives. The result that the trust levels of ET and NT on government were relative low suggested the weakness of risk communication in Korean government. Although ET and NT answered that they do not trust mass media, their behaviors were affected by them such as reading food labels in ET (39.4%) and reducing the consumption of food additives in NT (50%). They also indicated mass media's problem of sensitive approach on food additives and asked the urgent reaction of government by providing sound information through experts on food additives. Above results revealed that ET and NT have different perceptions and information needs on food additives, therefore, proper risk communication should be provided for them to serve as dietary educators for elementary school children.

Assessment of Demand and Use of Fresh-Cut Produce in School Foodservice and Restaurant Industries (학교급식 및 외식업체에서의 신선편이 농산물 사용실태 및 요구도 평가)

  • Sun, Shih-Hui;Kim, Ju-Hee;Kim, Su-Jin;Park, Hye-Young;Kim, Gi-Chang;Kim, Haeng-Ran;Yoon, Ki-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.6
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    • pp.909-919
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    • 2010
  • The purpose of this study was to investigate the demand and use of fresh-cut produce in school foodservice and restaurant industries. The subjects of this survey study were 200 school nutritionists and 70 cooks or managers in the restaurant industry nationwide. The data were collected by means of self-administered or e-mail questionnaires. Data analysis was completed using the SPSS window (ver. 12.0) program including frequency, $\chi^2$-test and t-test. Survey questions assessed the general characteristic of respondents, and the supply, use, and demand of fresh-cut produce in school foodservice and restaurant industries. Over 74% of the subjects have used fresh-cut produce. Most of the school foodservice (84.0%) kept fresh-cut produce for one day, while restaurant industry (28.3%) kept them up to three days. The nutritionists of school foodservice and managers of restaurant industry considered origin and date of production as the most important factor, respectively, when fresh-cut produce were being used. Fresh-cut root vegetable, such as potato and carrot was used mostly. The main reason not to use the fresh cut produce was due to the distrust of the fresh-cut produce safety in school foodservice and cost in restaurant industry. The main problem in fresh-cut produce use was the need of rewashing (29.9%) in school foodservice and irregular size (39.0%) in restaurant industry. These results indicate that the quality standard and size specification must be prepared with production guideline of safe fresh-cut produce.