• Title/Summary/Keyword: Transition process

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STOCHASTIC FRAGMENTATION AND SOME SUFFICIENT CONDITIONS FOR SHATTERING TRANSITION

  • Jeon, In-Tae
    • Journal of the Korean Mathematical Society
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    • v.39 no.4
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    • pp.543-558
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    • 2002
  • We investigate the fragmentation process developed by Kolmogorov and Filippov, which has been studied extensively by many physicists (independently for some time). One of the most interesting phenomena is the shattering (or disintegration of mass) transition which is considered a counterpart of the well known gelation phenomenon in the coagulation process. Though no masses are subtracted from the system during the break-up process, the total mass decreases in finite time. The occurrence of shattering transition is explained as due to the decomposition of the mass into an infinite number of particles of zero mass. It is known only that shattering phenomena occur for some special types of break-up rates. In this paper, by considering the n-particle system of stochastic fragmentation processes, we find general conditions of the rates which guarantee the occurrence of the shattering transition.

In Process Monitoring of Dynamic Resistance during Resistance Spot Welding of Aluminum to Steel using Transition Insert (Transition Insert를 이용한 알루미늄과 강판의 저항점용접에서 동저항측정을 통한 모니터링)

  • Jang, Hui Seok
    • Journal of Welding and Joining
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    • v.18 no.2
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    • pp.239-239
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    • 2000
  • Automobile manufacturers have employed resistance spot welding(RSW) to join steel sheets for structural rigidity o automobile body. Driven by the need to reduce weight and fuel consumption, car companies have been evaluating aluminum intensive vehicles(AIVs) as a way to reduce vehicle weight without downsizing. During the transition from all steel-construction vehicle body to aluminum intensive body, joining aluminum to steel sheets emerges as a serious contender in automobile body. This paper deals with application of transition material to RSW aluminum to steel. Placing transition material insert between the aluminum/steel interface was found very effective to overcome incompatibility between aluminum and steel. Use of transition insert allows for two separate weld muggets to be formed in their respective aluminum/ aluminum and steel/ steel interfaces. This RSW process was monitored with the aid of dynamic resistance sampling. Typical patterns in sampled dynamic resistance curves indicated formation of sound nugget. (Received February 28, 2000)

In Process Monitoring of Dynamic Resistance during Resistance Spot Welding of Aluminum to Steel using Transition Insert (Transition Insert를 이용한 알루미늄과 강판의 저항점용접에서 동저항측정을 통한 모니터링)

    • Journal of Welding and Joining
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    • v.18 no.2
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    • pp.112-118
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    • 2000
  • Automobile manufacturers have employed resistance spot welding(RSW) to join steel sheets for structural rigidity of automobile body. Driven by the need to reduce weight and fuel consumption, car companies have been evaluating aluminum intensive vehicles(AIVs) as a way to reduce vehicle weight without downsizing. During the transition from all steel-construction vehicle body to aluminum intensive body, joining aluminum to steel sheets emerges as a serious contender in automobile body. This paper deals with application of transition material to RSW aluminum to steel. Placing transition material insert between the aluminum/steel interface was found very effective to overcome incompatibility between aluminum and steel. Use of transition insert allows for two separate weld nuggets to be formal in their respective aluminum/aluminum and steel/steel interfaces. This RSW process was monitored with the aid of dynamic resistance sampling. Typical patterns in sampled dynamic resistance curves indicated formation of sound nugget.

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Transition Condition of Microscopic Wear Mode for TiN Coating by SEM Tribosystem (SEM Tribosystem에 의한 TiN피막의 미시적 마모형태의 천이 조건)

  • Moon, Bong-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.3
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    • pp.100-107
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    • 2011
  • To evaluate the wear characteristics of very thin ceramic coated layer, it is very important to investigate its wear process in great detail. An effective method for investigating the wear of a thin layer is the observation of wear process in microscopic detail, using in-situ system. In this study, based on the SEM Tribosystem as in-situ system, the microscopic wear mode of TiN coatings was investigated in repeated sliding. Consequently, four modes were revealed for TiN coatings: Ploughing, powder formation, flake formation and coating delimitation. Sc(Severity of contact) can clarify transition condition of those microscopic wear modes.

MicroRNAs as critical regulators of the endothelial to mesenchymal transition in vascular biology

  • Kim, Jongmin
    • BMB Reports
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    • v.51 no.2
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    • pp.65-72
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    • 2018
  • The endothelial to mesenchymal transition (EndMT) is a newly recognized, fundamental biological process involved in development and tissue regeneration, as well as pathological processes such as the complications of diabetes, fibrosis and pulmonary arterial hypertension. The EndMT process is tightly controlled by diverse signaling networks, similar to the epithelial to mesenchymal transition. Accumulating evidence suggests that microRNAs (miRNAs) are key regulators of this network, with the capacity to target multiple messenger RNAs involved in the EndMT process as well as in the regulation of disease progression. Thus, it is highly important to understand the molecular basis of miRNA control of EndMT. This review highlights the current fund of knowledge regarding the known links between miRNAs and the EndMT process, with a focus on the mechanism that regulates associated signaling pathways and discusses the potential for the EndMT as a therapeutic target to treat many diseases.

Pre-Parent Education Program Model for Couples in Transition to parenthood (부모기 전이기의 예비부모교육 프로그램 모형 개발: 부모되는 길라잡이)

  • 고선주
    • Journal of the Korean Home Economics Association
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    • v.36 no.5
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    • pp.167-185
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    • 1998
  • The propose of this study was to develop the new pre-parent education program for couples in i=transition to parenthood. This program was consisted three process, total eight sessions. The first process(the basic process) has two sessions. This process was designed to understand the whole parenthood, and to cope the role strain in early parenting period. The second process has three sessions, designed to enrich the marital relationship before the baby was born. And the Third process(parent-child process) has three sessions, too. Especially in last sessions, parent can exercise infant caring, and adapt fetus to their family member.

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A Study on Transition Process and factor of Exhibition Design - Based on the Exhibition's Transition in the Independence Hall - (전시디자인의 변천과정과 요인에 관한 연구 - 독립기념관의 시기별 전시변화를 중심으로 -)

  • Kwon, Soon-Kwan
    • Korean Institute of Interior Design Journal
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    • v.15 no.5 s.58
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    • pp.265-272
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    • 2006
  • Traditionally exhibition design as been restricted to architectural, interior, and lighting design, but recently it has begun to overlap into environmental, performance, and installation art. Exhibition design also increasingly involves the application of film, fashion, and the new media. In the past, exhibits were arranged and displayed for the visitor to view directly, but with the development of more effective exhibit media a connection has been created between the exhibit and the visitor. However exhibition design has reached the limits of continuous growth without background theory, when now it must take Into consideration the museum's activation and the importance of the exhibition's design. Exhibition design has developed and grown rapidly since the Taejeon Expo in 1993, but it is a difficult development without a theoretical structure. The flow of exhibition design must be systemized, as the systemization of the transition process of exhibition design has not yet been achieved. This study aims to present an arrangement of exhibition design flow, and to investigate the variation factors in the transition process of exhibition design and exhibit medium development, based on the 18 year history of the Independence Hall that introduced the first systematic planning of an exhibition in 1987.

Role Transition from Clinical Nurse to Case Manager for Medical-aid Beneficiaries: Taking Root in a Barren Land (임상간호사에서 의료급여관리사로의 역할 전이 과정: '척박한 땅에 뿌리내리기')

  • Park, Eun-Jun;Kim, Chun-Mi;Lim, Seung-Joo
    • Journal of Korean Academy of Nursing
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    • v.42 no.2
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    • pp.149-160
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    • 2012
  • Purpose: The purpose of this study was to explain the role transition process to nurse case managers (NCMs) for Medical-aid beneficiaries in Korea. Methods: Fourteen NCMs were interviewed regarding their experiences of becoming proficient in the new role of case manger. Data were analyzed through the application of grounded theory. Results: 'Taking root in a barren land' was the core category explaining the role transition process of NCMs. They engaged in four stages: launching, trial and error, proficiency, and wait-and-see stages. NCMs showed not only fear but also passion for case management practice. Despite their passion and effort, NCMs went through a period of trial and error. After becoming skilled, NCMs went through a stage of wait-and-see often because of job insecurity related to temporary position or few opportunities for promotion. Factors influencing NCMs' role transition process included their understanding of client characteristics, belief in case management, and support from their colleagues and families. Conclusion: NCMs experience many challenges in the process of becoming proficient NCMs. To help with their role transition, there is a need for education programs, preceptorship programs, research on their roles and functions, and regulation for securing NCMs' employment and career stability.

Transition Experiment and Socially-oriented R&D Program (시스템 전환론의 관점에서 본 사회문제 해결형 연구개발사업의 발전 방향)

  • Song, Wichin;Seong, Jieun
    • Journal of Technology Innovation
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    • v.22 no.4
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    • pp.89-116
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    • 2014
  • Socially-oriented R&D programs aimed at solving societal problem rather than scientific and industrial fruits have started recently. Societal problem is recognized as dilemma since this problem related to various stakeholders. And this is not solved with single program and needed long-term process. So the perspective of socio-technical system transition including technological and institutional change is needed. This paper suggests policy implication of Socially-oriented R&D programs from socio-technical system transition perspective. 'Transitioning of Socially-oriented R&D program' is the key concept of restructuring the program for the system transition. The establishment of multi-layer transition governance and the transition vision-making and transition experiment planning are the key process of transitioning the R&D program. This paper suggests the ways and issues of implementing this process in Socially-oriented R&D program.

Electrical Phase Transition of Poly (4,4'-Aminotriphenylene Hexafluoroisopropylidenediphthalimide) by Photogenerated Charged Carrier Injection

  • Im, Gyu-Uk;Lee, Gyeong-Jae;Lee, Mun-Ho;Gang, Tae-Hui;Jeong, Seok-Min;Yang, Mi-Hyeon;Kumar, Yogesh
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.266-266
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    • 2013
  • We show a set-up of poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found in contrast to the Al/6F-TPA PI/Al structure, leading to a write-once-readmany behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

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