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.

Time-Varying Signal Parameter Estimation by Variable Fading Memory Kalman Filtering

Lee, Sang-Wook,Lim, Jun-Seok,Sung, Koeng-Mo The Acoustical Society of Korea 1998 韓國音響學會誌 Vol.17 No.e3

This paper prolposes a VFM (Variable Fading Memory)Kalman filtering and applies it to the parameter estimation for time-varying signals. By adaptively calculating the fading memory, the proposed algorithm does not require any predetermined fading memory when estimating the time-varying signal parameter. Moreover, the proposed algorithm has faster convergence speed than fixed fading memory one in case the signal contains an impulsive outlier. The performance of parameter estimation for time-varying signal is evaluated by computer simulation for two cases, one of which is the chirp signal whose frequency varies linearly with time and the other is the chip signal with an impulsive outlier. The experimental results show that the VFM Kalman filtering estimates the parameter of the chirp signal more rapidly than the fixed fading memory one in the region of an outlier.

Unexpected Multiple Organ Infarctions in a Poisoned Patient

Sung Wook Park,Sang-Kyoon Han,염석란,Soon-Chang Park,Sung-Hwa Lee 대한중환자의학회 2015 Acute and Critical Care Vol.30 No.3

Predisposing factors for venous thrombosis can be identified in the majority of patients with established venous thromboembolism (VTE). However, an obvious precipitant may not be identified during the initial evaluation of such patients. In the present case, a 47-year-old female presented to the emergency department of our hospital after ingesting multiple drugs. She had no VTE-related risk factors or previous episodes, nor any family history of VTE. After admission to the intensive care unit sudden hypoxemia developed, and during the evaluation cerebral, renal, and splenic infarctions with pulmonary embolisms were diagnosed. However, the sources of the emboli could not be identified by transthoracic echocardiography or computed tomography angiography. Protein C deficiency was identified several days later. We recommend that hypercoagulable states be taken into consideration, especially when unexplained thromboembolic events develop in multiple or unusual venous sites.

Original Article : Isolation of a Marine Bacterium Capable of Biodegrading Poly(butylene succinate)

( Sang Jun Lee ),( Eun Hee Park ),( Yun Hee Han ),( Young Ok Kim ),( Seong Wook Park ) 한국수산과학회(구 한국수산학회) 2013 Fisheries and Aquatic Sciences Vol.16 No.1

We developed a poly(butylene succinate) (PBS) indicator plate and isolated a marine bacterial colony capable of biodegrading PBS based on the appearance of a clear zone. Growth of the PBS-2 isolate was observed over 4 days of culture at 37°C in PBS-tryptone basal liquid medium, but not in PBS-deprived control medium. The PBS-2 isolate was named Paenibacillus sp. PBS-2 based on 16S rDNA gene sequencing. The PBS-biodegrading marine bacterium isolated in this study will contribute to the effective management of PBS waste problems in marine environments.

A CMOS Outphasing Transmitter Using Two Wideband Phase Modulators

Lee, Sung-Ho,Kim, Ki-Hyun,Song, Jae-Hoon,Lee, Kang-Yoon,Nam, Sang-Wook The Institute of Electronics and Information Engin 2011 Journal of semiconductor technology and science Vol.11 No.4

This paper describes a CMOS outphasing transmitter using two wideband phase modulators. The proposed architecture can simplify the overall outphasing transmitter architecture using two-point phase modulation in phase-locked loop, which eliminates the necessity digital-to-analog converters, filters, and mixers. This architecture is verified with a WCDMA signal at 1.65 GHz. The prototype is fabricated in standard 130 nm CMOS technology. The measurement results satisfied the spectrum mask and 4.9% EVM performance.

Altered Cultivar Resistance of Kimchi Cabbage Seedlings Mediated by Salicylic Acid, Jasmonic Acid and Ethylene

Lee, Young Hee,Kim, Sang Hee,Yun, Byung-Wook,Hong, Jeum Kyu The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.3

Two cultivars Buram-3-ho (susceptible) and CR-Hagwang (moderate resistant) of kimchi cabbage seedlings showed differential defense responses to anthracnose (Colletotrichum higginsianum), black spot (Alternaria brassicicola) and black rot (Xanthomonas campestris pv. campestris, Xcc) diseases in our previous study. Defense-related hormones salicylic acid (SA), jasmonic acid (JA) and ethylene led to different transcriptional regulation of pathogenesis-related (PR) gene expression in both cultivars. In this study, exogenous application of SA suppressed basal defenses to C. higginsianum in the 1st leaves of the susceptible cultivar and cultivar resistance of the 2nd leaves of the resistant cultivar. SA also enhanced susceptibility of the susceptible cultivar to A. brassicicola. By contrast, SA elevated disease resistance to Xcc in the resistant cultivar, but not in the susceptible cultivar. Methyl jasmonate (MJ) treatment did not affect the disease resistance to C. higginsianum and Xcc in either cultivar, but it compromised the disease resistance to A. brassicicola in the resistant cultivar. Treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) ethylene precursor did not change resistance of the either cultivar to C. higginsianum and Xcc. Effect of ACC pretreatment on the resistance to A. brassicicola was not distinguished between susceptible and resistant cultivars, because cultivar resistance of the resistant cultivar was lost by prolonged moist dark conditions. Taken together, exogenously applied SA, JA and ethylene altered defense signaling crosstalk to three diseases of anthracnose, black spot and black rot in a cultivar-dependent manner.