Evaluation of Hot Deformation and Dynamic Recrystallization Behaviors of Advanced Reduced-Activated Alloy (ARAA)

Sang‑Wook Kim,Hyeon‑Woo Son,Taek‑Kyun Jung,Young‑Bum Chun,Yi‑Hyun Park,Ji‑Woon Lee,Soong‑Keun Hyun 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.4

The hot deformation behavior of advanced reduced-activation alloy (ARAA) was investigated using hot torsion tests. Thefl ow stress decreased as deformation temperature increased and as strain rate decreased. The fl ow behavior demonstratedthe typical dynamic recrystallization (DRX). Based on the constitutive analysis of peak stress, the activation energy for hotdeformation was found to be 330.3 kJ mol −1 . Peak stress was analyzed as a function of the Zener–Hollomon parameter, andcalculated and experimental values were in good agreement. A DRX kinetic model for ARAA was derived with deformationconditions based on the Avrami-type model. It was confi rmed that the volume fraction of dynamically recrystallized grainsincreased as deformation temperature increased and as strain rate decreased. The necklace structure and grain boundarybulging were observed in the deformed microstructure of ARAA. The suggested DRX mechanism for ARAA during hotworking is discontinuous DRX.

생활체육참가정도와 Wellness지수, 생활만족의 관계

김상국(Kim Sang-Kook),이광욱(Lee Kwang-Wook) 한국체육과학회 2005 한국체육과학회지 Vol.14 No.2

The purpose of this study was to examine the relationships among leisure sports participation, wellness inventory and life satisfaction, The subjects were 645 adults(male=348; female=297) aged more than 20 years who participated in community-based leisure sports programs of the fitness clubs in Seoul and Incheon City, Korea, The degree of leisure sports participation; items on the Wellness scale developed and used by Kim Sang-kuk based on Wellness: Concepts and Application developed by Anspaugh et al.(l994); and the Korean version of the Satisfaction with Life scale(SWLS) developed by Diener, Emons, Larsen & Griffin(1985) translated and used by Lee Jong-kil(1992). The validity of the questionnaire was verified through specialists' meeting, the pilot test, and exploratory and confirmatory factor analysis. The reliability of the questionnaire was found to be Cronbach' s α=.66~.83. The methods of statistics used to analyze the collected data were correlation analysis and multiple regression using SPSS WIN 11.5. As a result, the following findings were obtained: First, it was found that the degree of leisure sports participation had an effect on the wellness inventory. That is, participants who participated in the leisure sports program longer, more frequently, and more actively had the higher level of recognition on the wellness inventory than any other group. Second, it was found that the degree of leisure sports participation had an effect on the life satisfaction. That is, participants who participated in the leisure sports program longer, more frequently, and more actively the higher level of recognition on the life satisfaction than any other group. Third, it was found that the wellness inventory had an effect on the life satisfaction. That is, the participants who were highly conscious of physical, social, mental health domains as subfactors of the wellness inventory had the higher level of life satisfaction.

해외사례 벤치마킹에 기반한 국내 CM 대가체계 개선 시사점 도출

김상범,이정대,김재욱,Kim, Sang-Bum,Lee, Jeong-Dae,Kim, Jae-Wook 한국건설관리학회 2008 건설관리 : 한국건설관리학회 학회지 Vol.9 No.1

국내 CM은 2001년 건설산업기본법에 의해 개념과 범위가 정의된 후 지속적인 성장을 계속해 오고 있다. 하지만, 이러한 CM 제도에 기반한 성장에도 불구하고 국내에서의 CM 적용성과는 기대치에 비해 상대적으로 낮은 것으로 나타났다. 그 주요원인의 하나로 국내 CM제도가 책임감리에 비하여 업무범위가 넓지만, 대가기준은 책임감리에 비해 낮기 때문인 것으로 분석되었다. 따라서, 국내 CM 대가체계의 합리적인 기준을 정립하는 것이 시급할 것으로 판단된다. 본 연구에서는 CM 대가체계의 합리적인 기준을 마련하기 위하여 CMAA, ASCE, DOE, DOL 등의 다양한 해외사례 벤치마킹 연구를 통하여 국내 CM 대가체계를 비교하여 대가 상승요인을 추정하고 대가산정 개선방향을 제시하였다. 분석결과 대가수준은 해외에 비하여 현저하게 낮은 수준인 것으로 판단되었으며, 업무범위는 해외와 비교하여 그 폭이 좁으며 획일적인 구조를 가진 것으로 분석되었다. 따라서, 본 연구에서는 글로벌스탠다드에 따르는 국내 CM 대가체계를 개선하기 위하여 실비정액보수가산(Cost Plus Fixed Fee) 방식을 제시하고, 입 낙찰 전반에 걸친 CM 대가체계에 대한 기준(Framework)을 제시하였다. The Korean Construction Industry significantly contributed to the Korean economic development not only by preparing the domestic infrastructure but also by successfully conducting various international projects. However, major incidents such as the collapse of Sung-Su Bridge and Sam-Pung Department Store along with stagnation of Korean Economy have raised questions about underlying systematic problems of the Korean Construction Industry. As a solution to resurrect the Korean Construction Industry, the Construction Management (CM) system introduced in late 1990's and increasingly utilized as an innovative delivery system. Despite of the fast growth of CM, the performance of CM has not been up to the hype and low CM fee has been identified as one of the main reasons of unsatisfactory CM performance. Therefore, this research attempted to propose ways of improving 'CM Fee Guidelines' published by Korean Ministry of Construction and Transportation by conducting a benchmarking study on Global Standards of estimating CM Fee. International organizations benchmarked in this research include CMAA, ASCE, DOL, DOE, etc. Various investigation and analysis revealed that Korean 'CM Fee Guidelines' need to significantly modified comparing to Global Standards. This research also tried to prepare recommendations to improve the CM deliver system focusing on the 'Method of CM Fee Estimation' and Selection of a CM firm as an owner's agent.

Interactions between Chicken Salt-soluble Meat Proteins and Makgeolli Lees Fiber in Heat-induced Gels

Yun Sang Choi,Kwoan Sik Park,Hack Youn Kim,Hyun Wook Kim,Dong Heon Song,Hai Jung Chung,Ju Woon Lee,Cheon Jei Kim 한국축산식품학회 2011 한국축산식품학회지 Vol.31 No.6

The technological effects of Makgeolli lees fiber (0, 0.5, 1.0, 2.0, and 4.0%) on chicken salt-soluble breast meat proteins in a model system on proximate composition, physicochemical properties, and textural properties were investigated. Makgeolli lees fiber was obtained from Makgeolli brew processing, and the by-products showed good dietary fiber. The moisture and ash contents, water holding capacity, redness, yellowness, hardness, and apparent viscosity of chicken salt-soluble meat protein heat-induced gel systems with Makgeolli lees fiber were all higher than the control without Makgeolli lees fiber. However, protein solubility and electrophoretic patterns did not differ among the control and treatments with Makgeolli lees fiber samples. The chicken salt-soluble protein heat-induced gel systems incorporating Makgeolli lees fiber had improved water holding capacity, textural properties, and viscosity due to Makgeolli lees fiber addition. These results suggest that the addition of 4.0% Makgeolli lees fiber to gel is helpful to improve the physical properties of heat-induced gels.

Interactions between Chicken Salt-soluble Meat Proteins and Makgeolli Lees Fiber in Heat-induced Gels

Choi, Yun-Sang,Park, Kwoan-Sik,Kim, Hack-Youn,Kim, Hyun-Wook,Song, Dong-Heon,Chung, Hai-Jung,Lee, Ju-Woon,Kim, Cheon-Jei Korean Society for Food Science of Animal Resource 2011 한국축산식품학회지 Vol.31 No.6

The technological effects of Makgeolli lees fiber (0, 0.5, 1.0, 2.0, and 4.0%) on chicken salt-soluble breast meat proteins in a model system on proximate composition, physicochemical properties, and textural properties were investigated. Makgeolli lees fiber was obtained from Makgeolli brew processing, and the by-products showed good dietary fiber. The moisture and ash contents, water holding capacity, redness, yellowness, hardness, and apparent viscosity of chicken salt-soluble meat protein heat-induced gel systems with Makgeolli lees fiber were all higher than the control without Makgeolli lees fiber. However, protein solubility and electrophoretic patterns did not differ among the control and treatments with Makgeolli lees fiber samples. The chicken salt-soluble protein heat-induced gel systems incorporating Makgeolli lees fiber had improved water holding capacity, textural properties, and viscosity due to Makgeolli lees fiber addition. These results suggest that the addition of 4.0% Makgeolli lees fiber to gel is helpful to improve the physical properties of heat-induced gels.

A High Resolution 3D building modeling for creating a virtual test bed for the U-City

Sang-Moo Lee,Mu-Wook, Pyeon,Su-Jung Moon,Min-Cheol Jeon,Jang-Ryul Kim 한국콘텐츠학회 2010 ICCC International Digital Design Invitation Exhib Vol.2010 No.12

Recurrence of Small Cerebral Aneurysms (< 4 mm) Treated Endovascularly Using Target® NanoTM Coils

Sung Min Kim,Hyun Gon Lee,Byung Sam Choi,Jung Soo Kim,Sungjoon Lee,Hae Yu Kim,Sung Tae Kim,Young-Gyun Jeong,Jin Wook Baek,Hae Woong Jeong,Sung-Chul Jin 대한뇌혈관외과학회 2018 Journal of Cerebrovascular and Endovascular Neuros Vol.20 No.2

Objective : In our series, endovascular coiling with Target® NanoTM coils (Stryker Neurovascular, Fremont, CA, USA) with diameters of 1 or 1.5 mm exhibited favorable technical feasibility in the treatment of small cerebral aneurysms (< 4 mm). However, little is known about the recurrence of small cerebral aneurysms treated using Target® NanoTM coils. We investigated recurrence following the treatment of small cerebral aneurysms using Target® NanoTM coils. Materials and Methods : Between January 2012 and November 2013, 143 patients with 148 small cerebral aneurysms (< 4 mm) were included our study. A total of 135 cerebral aneurysms (91.2%) were unruptured; 45 cerebral aneurysms (30.4%) were treated by endovascular coiling using Target® NanoTM coils. Follow-up radiological images were obtained for 132 cerebral aneurysms (89.2%) over a range of 3 to 58 months (mean, 34.3 months; standard deviation, 14.2). Results : In the group treated with Target® NanoTM coils, radiological outcomes revealed complete occlusion in 33 (73.3%), residual necks in eight (17.8%), and residual sacs in four (8.9%) cases. Follow-up radiological outcomes revealed complete occlusion in 35 (77.8%) and residual necks in four (8.9%) cases that exhibited stable coil masses. In the group that was not treated with Target® NanoTM coils, radiological outcomes revealed complete occlusion in 69 (67%), residual necks in 18 (17.5%), and residual sacs in 16 (15.5%) cases. Follow-up radiological outcomes revealed complete occlusion in 87 (84.5%) and residual necks (5.8%) in six cases that exhibited stable coil masses. No significant differences were observed in the radiological outcomes or follow-up radiological outcomes between the two groups. No recurrences or retreatments occurred in our series. Conclusion : Endovascular treatment using Target® NanoTM coils may be a robust treatment option for small cerebral aneurysms (< 4 mm).

Ternary nanofiber matrices composed of PCL/black phosphorus/collagen to enhance osteodifferentiation

Lee, Yu Bin,Song, Su-Jin,Shin, Yong Cheol,Jung, Yu Jin,Kim, Bongju,Kang, Moon Sung,Kwon, Il Keun,Hyon, Suong-Hyu,Lee, Hyun Uk,Jung, Seo-Hyun,Lim, Dohyung,Han, Dong-Wook Elsevier 2019 Journal of industrial and engineering chemistry Vol.80 No.-

<P><B>Abstract</B></P> <P>Recently, considerable research has been made on the development of bone tissue engineering (BTE) scaffolds to support cellular behaviors. Here, black phosphorus-incorporated poly(ε-caprolactone) and collagen (PCL/BP/Col) nanofiber matrices were designed and their potential as BTE scaffolds were explored. The PCL/BP/Col nanofiber matrices were fabricated successfully by electrospinning, showing that they were suitable for supporting cell growth. The PCL/BP/Col nanofiber matrices could promote not only initial attachment and proliferation, but also osteodifferentiation of preosteoblasts. In conclusion, PCL/BP/Col nanofiber matrices possess excellent biocompatibility and improve osteogenic differentiation. Therefore, the PCL/BP/Col nanofiber matrices can be a promising candidate as a scaffold for BTE.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Black phosphorus (BP)-incorporated PCL and collagen nanofiber matrix is designed. </LI> <LI> PCL/BP/Col nanofiber matrix favorably supports cell growth. </LI> <LI> Biocompatibility and biofunctionality of PCL/BP/Col matrix is demonstrated. </LI> <LI> PCL/BP/Col matrix can stimulate spontaneous osteodifferentiation. </LI> <LI> PCL/BP/Col matrix can be employed as a bone tissue engineering scaffold. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Development and evaluation of a head bolus shielding for total skin electron irradiation (TSEI) technique

Wook-Geun Shin,Sung Young Lee,Hyeongmin Jin,Jeongho Kim,Seonghee Kang,Jung-in Kim,Seongmoon Jung 대한방사선방어학회 2021 대한방사선방어학회 학술발표회 논문요약집 Vol.2021 No.11

Biomimetic Engineering of a Generic Cell-on-Membrane Architecture by Microfluidic Engraving for On-Chip Bioassays

Lee, Sang-Wook,Noh, Ji-Yoon,Park, Seung Chul,Chung, Jin-Ho,Lee, Byoungho,Lee, Sin-Doo American Chemical Society 2012 Langmuir Vol.28 No.20

<P>We develop a biomimetic cell-on-membrane architecture in close-volume format which allows the interfacial biocompatibility and the reagent delivery capability for on-chip bioassays. The key concept lies in the microfluidic engraving of lipid membranes together with biological cells on a supported substrate with topographic patterns. The simultaneous engraving process of a different class of fluids is promoted by the front propagation of an air–water interface inside a flow-cell. This highly parallel, microfluidic cell-on-membrane approach opens a door to the natural biocompatibility in mimicking cellular stimuli-response behavior essential for diverse on-chip bioassays that can be precisely controlled in the spatial and temporal manner.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2012/langd5.2012.28.issue-20/la3010695/production/images/medium/la-2012-010695_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la3010695'>ACS Electronic Supporting Info</A></P>