• 제목/요약/키워드: Mass standards

검색결과 465건 처리시간 0.033초

Methods of analysis for buildings with uni-axial and bi-axial asymmetry in regions of lower seismicity

  • Lumantarna, Elisa;Lam, Nelson;Wilson, John
    • Earthquakes and Structures
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    • 제15권1호
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    • pp.81-95
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    • 2018
  • Most buildings feature core walls (and shear walls) that are placed eccentrically within the building to fulfil architectural requirements. Contemporary earthquake design standards require three dimensional (3D) dynamic analysis to be undertaken to analyse the imposed seismic actions on this type of buildings. A static method of analysis is always appealing to design practitioners because results from the analysis can always be evaluated independently by manual calculation techniques for quality control purposes. However, the equivalent static analysis method (also known as the lateral load method) which involves application of an equivalent static load at a certain distance from the center of mass of the buildings can generate results that contradict with results from dynamic analysis. In this paper the Generalised Force Method of analysis has been introduced for multi-storey buildings. Algebraic expressions have been derived to provide estimates for the edge displacement ratio taking into account the effects of dynamic torsional actions. The Generalised Force Method which is based on static principles has been shown to be able to make accurate estimates of torsional actions in seismic conditions. The method is illustrated by examples of two multi-storey buildings. Importantly, the black box syndrome of a 3D dynamic analysis of the building can be circumvented.

항공기 엔진에 의한 대기오염 (Air Pollution by Airplane Engines)

  • 김대식
    • 기술사
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    • 제32권5호
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    • pp.118-125
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    • 1999
  • Air pollutant emissions from airplane engines are estimated about 2 to 4 % of mobile source of USA and European countries which is not a large portion of current air pollution. But the passengers and airfreights are continuously increasing 5 to 7% annually and potential demands of air transportation services come to present, it could effect air pollutant emissions of USA will increase within 15 years. In case of our country, there has been continuous increase of air transportation service due to considerable economic growth in recent years and increase of air pollutant emissions of major international airports has followed. Rapid increase of air transportation due to launching of Inchon International Airport could effect air pollution dominantly. By this circumstance environmental specialist as well as mass communication raised necessity of air pollutant emission regulation from airplane engines. It is estimated that air pollutant emissions from airplane engines in our country is 2.7% of automobile sources, 10,809 ton, which is the same level as USA and European countries. It is increased by 12,2% compared to air pollutant emissions during 1996 and it will be increased more than a half of current air pollutant emission within 15 years due to our country's economic condition. Therefore implementation of airplane engine emissions regulation as well as test standards and accumulation of technology about characteristics of airplane engine emission and reduction method are needed. And continuous estimation of air pollutant emission from airplane engines and monitoring of increment as well as development of countermeasures by long term are necessary.

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3대가족 동거주택을 위한 수직 2호 1주택 아파트 재구성 연구 (A Study on the Vertical Unification, Two to One Remodeling for Three Generation Dwelling of Apartment Housing)

  • 손승광
    • 한국주거학회논문집
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    • 제14권3호
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    • pp.147-156
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    • 2003
  • A small apartment housings in Korea, which is built mass-product from 1980s, are dissatisfied, in spite of good condition, due to the growing living areas and changing lifestyle of the residents. Many of them confronted with slum areas and the kinds of housing stock accumulated much more in Korean contexts. For the existing small houses, it could be discuss an adaptation model to the increasing requirement standards of the house residents; wider living area, new facilities and a style of new residence. A social policy for elderly people who are handicap in physical and economical aspects, is home stay system rather than national support. But it is not easy to find the three generation family house in Korea context, specially apartment house. This paper deals with the vertical unification typology of two dwelling units to one, in order to supply three generation houses by remodel existing small apartment houses constructed by Korea National Housing Corporation. The use of convert houses into vertical expansion are expected to be a house of three generation family, it can also enhance privacy against conflictive activities in a house. And also the merging types of two dwelling units into one can be used as a device to get rid of the monotonous characteristics and gain diversity in the declining stock housing.

중국(中國)의 면조문화연구(麵條文化硏究) (A Study on Chinese Noodles)

  • 신계숙
    • 한국식생활문화학회지
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    • 제15권4호
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    • pp.307-312
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    • 2000
  • The purpose of this study is to understand the Chinese noodles(mian tiao). Wheat seems to have been cultivated 3-4,000 years before according to the archaeological evidences from the neolithic sites. The five grains(rice, millet, beans, barley, barnyard millet) already appeared in the period prior to Chin dynasty and were used as whole grain, but it was not until Chun Chu Zhan Guo period that the introduction of the flouring method stimulated the cultivation of wheat. In Chin-Han period, when water power and animal force were put into usage to facilitate the mass production of wheat flour, 'Bing', a designation for all the food made of wheat first appeared in the literature, and it was this 'Bing' that had later developed into noodles. In Wei Chin Nan Bei Chao period, roasted 'Bing', namely 'Kao-Bing' made its first appearance, and in Tang period, various noodles were created with the increase of restaurants specialized in noodles. In Song dynasty, 'La-Mian', the noodles stretched and beat from noodle dough, was first introduced, and in Yuan period, invention of drying method made the appearance of dried noodles, 'Gua-Mian', possible, which was good for easy and long preservation. Qing dynasty developed the noodles with a variety of assorted ingredients. The Chinese noodles are classified by various standards such as main ingredients, cooking methods, kinds of sauce, secondary ingredients, shape, eating method, flavor, and look.

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해운선사의 SEEMP 개선안에 관한 연구 (A Study on the Improvements of SEEMP of Shipping Companies)

  • 최보라;박충환;임남균
    • 해양환경안전학회지
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    • 제21권2호
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    • pp.147-153
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    • 2015
  • 국제해사기구는 선박기인 $CO_2$ 저감을 위해 SEEMP를 시행 하였다. 본 논문에서는 국제해사기구가 권고한 SEEMP 시행 방안과 세 해운선사의 SEEMP 적용 사례를 동일 기준으로 비교 분석 하였다. 이를 통해 적용상의 문제점을 파악하여 해운선사들이 SEEMP를 더욱 효율적으로 적용하기 위한 개선 방안을 제시하였다. 개선방안으로는 Company EEOI의 오류 수정, EEOI 데이터 획득 기간 통일, 에너지 효율 운항을 위한 조치사항 준수, 다양한 연료에 대한 $CO_2$ 환산 계수 제시, 국제해사기구의 공식적 기준을 통한 EEOI 목표값 설정이 있다.

LASER WELDING APPLICATION IN CAR BODY MANUFACTURING

  • Shin, Hyun-Oh;Chang, In-Sung;Jung, Chang-Ho
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.181-186
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    • 2002
  • Laser welding application for car body manufacturing has many advantages in the stiffness and the lightness of vehicle, the productivity of assembly line, and the degree of freedom in design. This presentation will express the innovation of car body manufacturing including parameter optimization, process modeling, and system integration. In this application the investment for systems was cut down dramatically by real time switching over the laser path between two welding stations. Points of technical discussion are as follows: optimization of parameters such as laser power, robot speed and trajectory, compact and useful design of jig & fixture to assure welding quality for 3 sheet-layer zinc-coated steel, system integration between 4kW Nd:YAG laser device and the other systems, on-line real time welding quality monitoring system, perfect safety standards for high power laser, minimization of consumption costs such as arc lamp, protective glass for optic, etc. Laser welding has found a place on Hyundai's production plant in conjunction with the startup of mass production of new sports car, and this production system is the result of a collaboration of its engineers. Outer side sheets are joined to inner side sheets by 122 stitch welds totally. And the length is about 2.4meter.

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Substituent Effect on Fragmentations and Ion-Molecule Reactions of Ionized Alkyn Alcohols

  • Choi, Sung-Seen;So, Hun-Young;Kim, Beom-Tae
    • Bulletin of the Korean Chemical Society
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    • 제26권4호
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    • pp.609-613
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    • 2005
  • The fragmentation patterns and ion-molecule reactions of two alkyn alcohols, 2-propyn-1-ol (HC≡$CCH_2$OH) and 2-methyl-3-butyn-2-ol (HC≡CC($CH_3)_2$OH), were investigated using Fourier transform mass spectrometry (FTMS). The most abundant fragment ions formed from the molecular ions were [M-H]$^+$ for 2-propyn-1-ol and [M-$CH_3]^+$ for 2-methyl-3-butyn-2-ol. The dehydrated ion, [M-$H_2O]^+$ was formed only from 2-propyn-1-ol in which $\alpha$ -hydrogen atoms were available for $\alpha,\;\alpha$ -elimination reaction. The protonated molecules were dissociated into [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ through dehydration and deacetylenylation processes. The formations of [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ from 2-methyl-3-butyn-2-ol were more favorable than those from 2-propyn-1-ol due to stabilization by two methyl groups at $\alpha$ -carbon. Ion-neutral complexes formed at long ion trapping time gave dehydrated and/or deacetylenylated ion products by further dissociation.

웨어러블 스마트기기의 표준화 및 시험인증 연구 (Study of Standardization and Test Certification for Wearable Smart Devices)

  • 한태수;김덕기;권오영;좌성훈
    • 마이크로전자및패키징학회지
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    • 제23권4호
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    • pp.11-18
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    • 2016
  • Today, wearable technology products are used in a wide range of consumer, healthcare, bio-medical, and industrial applications. The market for wearable technology products is expected to increase dramatically over the next several years. In addition, concerns for safety, performance and reliability of wearable products keep increasing and will be essential for widespread acceptance in the marketplace. Wearable smart devices, which are generally in contact with the human body and skin, are exposed to the risk of the electric shock, burn, and explosion. Therefore, the standardization of wearable devices in terms of human safety and reliability should be very important. Furthermore, the development of test method and test certification of the wearable products will be one of the key technology for mass production. Such standardization and certification will help consumers to choose the safest and best quality wearable devices and allow manufacturers to prove the safety and quality of their products, thereby helping them to gain a competitive technology. This paper discusses the current status of the wearable smart devices as well as the standardization and test certification applicable to wearable technology products.

소형 위성용 고해상도 광학카메라의 광학정렬 (Optical alignment of a high-resolution optical earth observation camera for small satellites)

  • Kim, Eugene D.;Park, Young-Wan;Kang, Myung-Seok;Kim, Ee-Eul;Yang, Ho-Soon
    • 한국광학회지
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    • 제15권4호
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    • pp.391-396
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    • 2004
  • 인공위성용 지구관측 카메라나 우주관측 망원경에는 크기와 무게의 제약 때문에 Cassegrain 방식의 망원경이 많이 쓰인다. 이와 같은 우주광학계의 성공적인 임무수행을 위해서는 망원경부의 정밀한 광학정렬이 매우 중요하다. 본 논문에서는 정렬 정밀도에 따른 Cassegrain 방식 망원경부의 광학정렬 방법 중, 간섭무늬를 이용한 방법, 파면오차를 이용한 방법, 역최적화 광학정렬 방법 등을 모사를 통해 제시하고, 현재 개발 중인 구경 300 mm급 소형 위성용 카메라에 적용한 광학정렬 실험 결과를 정리한다.

국외 NaTech 사례연구를 통한 재난관리 방안 고찰 (Discussions on the Disaster Management for NaTech based on the Foreign Case Studies)

  • 유병태;백종배;고재욱
    • 한국안전학회지
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    • 제31권1호
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    • pp.111-117
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    • 2016
  • Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Technological disasters triggered by natural disasters are referred to as NaTech(Natural Disaster Triggered Technological Disaster). These trends increase the probability of catastrophic future disasters and the potential for mass human exposure to hazardous materials released during disasters. In the present study, we proposed some methods for effective disaster management by conducting case study of major NaTech. First, establishing information sharing system of chemical accident for stakeholders and improving disaster manuals and standards of central and local government and co-operation support system. Second, activating information service of emergency planning and community right to know. Third, improving the integrated chemical accident database including NaTech accidents.