• Title/Summary/Keyword: 자재성능

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Fuorine-Containing High Temperature Polymers for Microelectronic Applications (불소를 함유하는 전자재료용 내열성 고분자)

  • Kim, Sang Youl
    • Polymer Science and Technology
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    • v.3 no.1
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    • pp.36-43
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    • 1992
  • Trifluoromethyl group을 내열성고분자의 주쇄에 도입하면 내열성의 큰 손실없이 용해도의 증가 및 유전상수의 감소등 절연재료로서의 성능을 향상시켜 주지만, 유연한기의 도입에 따른 $T_g$의 저하등 부정적인 효과도 나타낸다. 분자구조설계에 의해 기존 고분자재료의 성능을 향상시키려는 시도는 흔히 향상되어지는 성질들에 반비례하여 어는 다른 성질의 저하를 초래하는 경향이 있으나, 유전상수나 가공성 이외에도 낮은 열팽창계수를 갖는 polyimides, 열경화성수지인 poly(benzocyclobutene) 등의 packaging 재료로서의 개발등, 낮은 절연율, 내열성, 가공성, 접착력, 적절한 열팽창계수 및 기계적 성질 등 가능한 모든 필요성질을 동시에 최대한 만족시키는 고분자재료에 대한 개발노력이 계속되어지고 있으며 장차 혁신적인 새로운 고분자 재료의 등장도 이루어지리라고 본다.

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Evaluation of sampling and analytical method for emission experiment of pollutants in building materials using small chamber (소형챔버를 이용한 건축자재 오염물질 방출시험방법 평가)

  • Lee, Suk-Jo;Jang, Seong-Ki;Kim, Mi-Hyun;Lee, Hong-Suk;Lim, Jun-Ho;Jang, Mee;Seo, Soo-Yun
    • Analytical Science and Technology
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    • v.18 no.4
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    • pp.344-354
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    • 2005
  • This study was carried out to evaluate the performance of a small chamber sampling and analytical method for the measurement of total volatile organic compounds (TVOC) and formaldehyde (HCHO) emission from building materials. While VOC was determined by the adsorbent tube sampling and sequential thermal desorption coupled with GC/MSD analysis, formaldehyde sampled with DNPH-silica cartridge was analyzed by HPLC. Wide-range performance criteria such as repeatability, desorption efficiency, emission chamber recovery test, duplicate precision, breakthrough volume and method detection limits were investigated for the evaluation of small chamber method. The overall precision of the small chamber sampling and analytical methods was estimated within 20~30% for target compounds. In conclusion, this study demonstrated that the small chamber sampling and analytical method can be reliably applied for the measurement of building materials pollutants.

고분자절연재료의 방전열화

  • 이덕출
    • 전기의세계
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    • v.25 no.6
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    • pp.40-44
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    • 1976
  • 근대산업의 에너지원으로서 전력수요의 급격한 증대에 수반하여 전력계통의 초고전압화, 관련기기의 소형화 및 장기간에 걸친 성능의 안정성, 신뢰성이 절실히 요망 하겠금 되었다. 이로 인하여 전기절욘재료에 요구되는 제성능도 일반적으로 고도화되고 점점 가혹한 조건이 부가되고 있는 실정이라 하겠다. 근년 고분자화학의 급속한 진보와 고분자성형기술의 발달에 의하여 등장한 합성고분자재료는 그 물리, 화학적 성질 특히 전기적 성질에 많은 특징을 가지고 있으며 그 성능이 점점 높이 평가되고 있어 고분자재료의 진출이야말로 전기기기절연의 양상에 일대 변화를 줄것이라 하여도 지나친 표현이 아니겠다. 이와같이 고분자가 전기절연재료로써의 가치는 물가구조로 부터 기대되는 우수한 유전성과 전기절연성이 높이 평가되고 있는 점이라 하겠다.

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Performance Analysis of WCDMA/TDD with indoor Environment in Building (빌딩내의 실내 환경을 고려한 WCDMA/TDD 시스템의 성능 분석)

  • 강도욱;우병훈;강희조
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.186-190
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    • 2002
  • 본 논문에서는 WCDMA/TDD시스템에서 실외 환경에 셀 간 간섭 모델과 빌딩내의 층 간 간섭 모델을 비교하여 성능을 분석하였다. 실내 빌딩 환경에서 층 간 간섭 분석 모델을 고려 시, 건축 자재에 의한 전파 투과손실로 인해 인접 셀로부터 오는 간섭의 영향이 작아짐으로 실외환경을 고려한 셀 간 간섭 모델에 비해 성능이 좋음을 알 수 있었다. 따라서 WCDMA/TDD시스템은 광범위한 교외지역이나 피코 셀로 설계된 도심지역보다 층 간 간섭 모델을 기반으로 둔 빌딩내 사무실 환경을 고려한 시스템 설계에 더 적합할 것이라 사료된다.

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A Study on Flame Spread Prevention of Sandwich Panel (복합자재 화재확산방지구조에 대한 연구)

  • Cho, Nam-Wook;Kim, Do-Hyun;Shim, Ji-Hun
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.84-90
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    • 2015
  • Multi-layered material (sandwich panel) consists of double-sided steel plate which is incombustible material or similar material and core material which is not incombustible material. In case of sandwich panel which uses combustible material as insulation, flames spread inside the steel plate at the time of fire so that it is difficult to extinguish fire from the outside and flames spread rapidly and may cause the building to collapse. The current Building Act requires the sandwich panel to secure fire-retardant performance according to the purpose and size of building. In this study, the fire spreading prevention structure applied to partial exterior walls was applied to multi-layered material and its effect was measured through full scale fire test and the possibility to secure fire safety of buildings by applying the fire spreading prevention structure to multi-layered material in future was presented.

Evaluation of Fracture Behaviours of Cementitious Composites by High-velocity Projectile Impact (고속 비상체 충격에 의한 시멘트 복합체의 파괴거동 평가)

  • Min, Ji-Young;Cho, Hyun-Woo;Lee, Jang-Hwa;Kim, Sung-Wook;Moon, Jae-Heum
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.6
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    • pp.55-62
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    • 2015
  • An importance of infrastructures' protection against crash or blast loading has been an emerging issue as structures are becoming much bigger and population densities in downtown are growing up. However, there exists no such a standard to evaluate the protection performance of construction material itself. Prior to building standards for protection assessment techniques, this study performed gas-gun propelled projectile impact tests with series of contact-type monitoring systems to investigate the applicability of each sensing type. Through the impact tests, failure modes and protection performances of both normal concrete and UHPC (Ultra High Performance Concrete) reinforced by steel fibers were also evaluated. The results showed that LVDT could be applicable for the impact test among contact-type sensors and UHPC with fibers had a remarkable potential to improve protection against impact loading.

Performance Evaluation of System Support Assembled with Reused Members (재사용 가설기자재로 조립된 시스템 동바리의 성능 평가)

  • Park, Jun-Beom;Jung, Wook;Bae, Sung-Jae;Kim, Chan-Jin;Yoon, Sung-Hyun;Yoon, Sang-Moon;Kim, Young-Suk;Kim, Jung-Yeol
    • Korean Journal of Construction Engineering and Management
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    • v.25 no.5
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    • pp.15-24
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    • 2024
  • System support is a facility that is temporarily installed to support vertical loads at construction sites, and is assembled and installed by reused individual members. These characteristics are likely to lead to poor performance of installed system supports, and even though it is institutionalized to check structural safety at the their design phase, accidents continue to occur at the construction site. Accordingly, safety management of system support is implemented through various institutional methods, but the current system does not consider the performance degradation of temporary facilities due to the reuse of individual temporary members. Therefore, the purpose of this study is to verify the performance of assembled system support. In order to do achieve this purpose, the authors divided individual system supports into unused and used groups and performed compression performance test with defined models assembled with those two groups of system supports. The results of this study are expected to be meaningful as a research case that can quantitatively evaluate safety systems and standards for the performance of existing temporary facilities and suggest directions for improving the safety management system of temporary facilities in the future.

Improvement of Performance Test Standards for Marine Pollution Prevention Materials and Chemicals (for Eco-toxicity Test) (해양오염방제 자재·약제의 성능시험기준 개선방안에 관한 연구(생태독성시험 항목))

  • Kim, Tae Won;Lee, Su Jin;Kim, Young Ryun;Lee, Moon Jin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.744-753
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    • 2021
  • This study suggests ways to improve the standard test method and judgment criterion for the "Eco-toxicity Test" based on the rules and regulations provided in 'performance and qualifying test standards for marine pollution prevention materials and chemicals' in the Republic of Korea. Compared with the relevant references of other countries, this study attempted to find the limitations in the existing standards. As for the growth inhibition test of algae using Skeletonema costatum as an indicator, applying comparative analysis to measure specific growth rates, together with statistical analysis, instead of applying current methods, judged by the appearance of colors from the culture medium was suggested. Considering the exponential growth phase of the test species, the test duration was suggested to be reduced to less than four days. For the test with fish as an indicator, resetting the appropriate body size was suggested to, show consistent sensitivity against chenicals applied during testing. Furthermore, it is necessary to consider the criteria needs, which should be established in reasonable and objective ways. For the testing species, marine rotifer, Brachionus plicatilis could be a replacement for Artemia sp., and a bivalve for fish in the test. To improve the performance effectiveness of the "Eco-toxicity test", it is worth considering the designation of accredited testing institutes, by placing it in the same loop. Thus it is also expected to have a reliable management system in place, having the capacity of cost calculation properly and adjusting testing items if required.

Battery Pack and Management System for Automated Guided Vehicle (AGV용 배터리 팩 및 관리시스템)

  • Nam, Jong-ha;Kang, Duk-ha;Hwang, Ho-seok;Park, Chan-hi;Lee, Heui-kwan;Park, Min-kee
    • Proceedings of the KIPE Conference
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    • 2011.07a
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    • pp.138-139
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    • 2011
  • 무인 운반차(AGV, Automated Guided Vehicle)은 1955년에 개발된 자재 운반용 무인운송 시스템으로 초기에는 제조 현장에서 자재의 운송에 국한되어 사용되었다. 최근에는 창고, 컨테이너 터미널 그리고 지하공간에서의 반복되는 실내/외 운송으로까지 그 사용이 확산되고 있다. AGV는 제조현장에서 제조 공정과 관련된 모든 자재의 이송에 적용되고 반복되는 운송의 형태에 사용되며, 실내 용도로는 수입, 저장, 분류, 반출, 이송과 공정 간의 파레트(Pallet) 이송에 사용되며, 비교적 작은 용량의 AGV가 이러한 제조현장에서 산업용도에 쓰이고 있다. AGV는 실내에서 주로 사용되는 환경적 특성상 배터리를 사용하며, 충전하거나 교환하여야 하며, 이에 소요되는 시간이 시스템의 성능에 큰 영향을 미친다. 대부분의 제조현장이나 배송센터에서 AGV는 비교적 짧은 거리를 운행하므로 대기 시간 중에 배터리를 충전하거나 교환이 가능하다. 하지만 비교적 장거리를 운행하는 시스템에서는 AGV의 가동률을 50% 이하로 유지하거나 온라인 충전 시스템을 구비하여야만 배터리 전압 강하에 의한 시스템의 마비를 예방할 수 있다.

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