• Title/Summary/Keyword: accelerators

Search Result 334, Processing Time 0.035 seconds

A Sduty on the Vulcanization Characteristic of Combined Accelerators in SBR Compounds ( II ) (SBR의 가황촉진제(加黃促進劑) 병용효과(倂用效果)에 의한 가황특성(加黃特性) 연구(硏究) ( II ))

  • Choi, Jae-Woon
    • Elastomers and Composites
    • /
    • v.17 no.4
    • /
    • pp.215-225
    • /
    • 1982
  • The purpose of this study is to get comparitive results on the combined accelerator systems comprised of MBT, MBTS, DPG and CBS with TMTD, TMTM and Zn-MDC to SBR compound. Vulcanization characterstics and physical properties of the combined accelerators have been studied by means of the Mooney viscometer, the Monsanto disc rheometer, tensile testing machine, aging chamber and so on. According to the test results, DPG, MBT and Zn-MDC system have show faster Mooney scorch time and optimum cure time than other systems. The Vulcanizate comprise of DPG, MBT and TMTD accelerator system has taken adventage of tensile strength, elongation, 100% modulus, resilience, compresion set.

  • PDF

How Should Techno Parks Innovate to Support Start-ups and Small and Medium-Sized Enterprises Effectively in the Era of the Fourth Industrial Revolution?

  • Cho, Inje;Lee, Eung-Hyun;Cho, Hoonje
    • World Technopolis Review
    • /
    • v.6 no.1
    • /
    • pp.4.1-4.15
    • /
    • 2017
  • In 1995, the Republic of Korea started to establish Techno Park (TP) in order to develop the regional industry while promoting the balanced development of the land. By 2008, 18TPs were established nationwide and have become cradles for developing local industries. And recently evolved forms of TP such as Daedeok Techno Valley and Pangyo Techno Valley emerged. In addition, 19 Centers for Creative Economy and Innovation (CCEI) were established nationwide and Tech-Incubator Program for start-ups (TIPS) was introduced to support and mentor start-ups. TPs in Korea become bureaucratic in course of time, and the new trial of innovation of TP is needed. In Korea, professional TIPS-accelerators mentoring and investing start-ups have a history of only five years. But they support and mentor start-ups efficiently, and have obtained good results. In this paper, we propose that TP attract TIPS-accelerators actively and collaborate with each other to support and mentor start-ups and SMEs effectively.

Failure Analysis of the Masking Tape for Airconditioner (에어컨 전선 마감 Tape 변색 및 냄새에 관한 고장분석 사례)

  • Seo, Sung-Mi;Choi, Dong-Jun;Park, Sang-Dunk
    • Journal of Applied Reliability
    • /
    • v.5 no.4
    • /
    • pp.405-412
    • /
    • 2005
  • In this paper, we verified the failure mechanism of the discolored masking tape wrapped around the wire and studied an improved case study as well. Masking tapes are poly(Vinylchloride-co-Methyl methacrylate) (PVC) and the wire connecting with indoor/outdoor components of the air conditioner is chloroprene(CR). The masking tape under. the ultraviolet ray was accelerated to discolor fivefold. The results determined reveal the discoloration of masking tapes as an elution of the additives, dephenyl Amine series antioxidants, in the connecting wire. When changed dephenyl Amine series to phenol series, we found that the degree of discoloration was dramatically decreased. Due to stink of Thiourea and Thiuram monosulfide, as accelerators in CR wire, we controlled the vulcanization temperature and time without using these accelerators and could get the wire not to smell bad with the equal mechanical properties.

  • PDF

Rapid hardening of polymer-modified mortars with accelerators (급경제를 이용한 폴리머 시멘트 모르타르의 속경성)

  • Jo, Young-Chul;Choi, Nak-Woon;Lee, Chol-Woong;Yang, Suk-Woo;So, Yang-Seob
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.11a
    • /
    • pp.731-734
    • /
    • 2004
  • Admixture compounds for reducing setting time and accelerating early strength development of redispersible polymer powder-modified mortars were made by mixing various inorganic accelerating inorganic materials. Redispersible polymer powder-modified mortars are prepared with various accelerator contents, and it was tested for setting time, flexural and compressive strengths. As a result, the accelerators contribute to strength development of the mortars in the early curing age of 12h or less. In the viewpoint of early strength development of redispersible polymer powder-modified mortars, an accelerator content of $20\%$ is recommended.

  • PDF

Shielding Design of Electron Beam Accelerators Using Supercomputer (슈퍼컴을 이용한 전자빔가속기의 차폐설계)

  • Kang, Won Gu;Kim, In Soo;Kuk, Sung Han;Kim, Jin Kyu;Han, Bum Soo;Jeong, Kwang Young;Kang, Chang Mu
    • Journal of Radiation Industry
    • /
    • v.4 no.1
    • /
    • pp.33-38
    • /
    • 2010
  • The MCNP5 neutron, electron, photon Monte Carlo transport program was installed on the KISTI's SUN Tachyon computer using the parallel programming. Electron beam accelerators were modeled and shielding calculations were performed in order to investigate the reduction of computation time in the supercomputer environment. It was observed that a speedup of 40 to 80 of computation time can be obtained using 64 CPUs compared to an IBM PC.

A Study of the Effects of the Innovativeness, Learning Orientation, Network Orientation, Financial Characteristics, Global Orientation of Startups and the role of Accelerators on the Internationalization Performance (스타트업의 혁신성, 학습지향성, 네트워크지향성, 재무적 특성, 글로벌지향성과 액셀러레이터의 역할이 국제화 성과에 미치는 영향에 관한 연구)

  • Dong Ki Lee;Kwang So Park
    • Korea Trade Review
    • /
    • v.47 no.1
    • /
    • pp.79-97
    • /
    • 2022
  • This study aims to analyze the effects of the characteristics of startups and the role of accelerators on internationalization performance. To achieve this purpose, we collected data from the management of 180 startups promoting overseas expansion. As a result of empirical analysis, it was confirmed that among the characteristics of startups, innovativeness, learning orientation, and global orientation had a significant effect on internationalization performance. In addition, it was confirmed that the role of the accelerator has a positive effect on the internationalization performance.