A1 7039合金의 피로 특성에 미치는 열처리의 영향

金熹載,李興周 陸軍士官學校 1984 한국군사학논집 Vol.26 No.-

Effect of heat treatment on the high cycle fatigue behavior of high strength aluminum alloy 7039 was examined by microcopy, mechanical and fatigue test. The elongated plateshaped grain by the effect of hot rolling and oxide or coarse super hardened particles, Cr compound(CrAl_7)were observed on the optical microscopy. The density of coarse inherent, θ phase(MgZn_2) was decreased as the time of artificial aging was increased. S1 specimen developed by holding at 480C for 2 hours, holding at room temperature for 72 hours and then aging at 120C for 24 hours was showed the most ex-cellent fatigue limit.

한류3.0 시대 속 궁중문화를 활용한 축제에 관하여 : 제 2회 궁중문화축전을 중심으로

김희재,최희수 글로벌문화콘텐츠학회 2016 글로벌문화콘텐츠학회 학술대회 Vol.2016 No.1

2016년 2번째 생일을 맞이한 궁중문화축전은 시민 200여명이 참여한 “1750시간여행 그날”이라는 참여형 프로그램과 화려한 볼거리를 선사한 “1892 왕의잔치”이라는 재현 프로그램 이 외에도 전시, 공연 프로그램등 다양하게 진행되었다. 이러한 궁중문화축전은 궁중문화를 활용한 축제로 자리매김하려고 한다. 일반적으로 축제는 글로벌 브랜드화를 목표로 하며, 궁중문화축전은 화려함으로 내국인과 외국인의 시선을 끌었고 소비자가 반응하는 자극적인 콘텐츠를 화려함으로 보여주었다. 하지만 궁중문화에서 화려함을 고집한다면 일시적으로 글로벌축제 브랜드로 자리 잡을 수 있을지도 모른다. 하지만 지속가능성이 의심되며, 콘텐츠의 고갈이라는 문제점이 발생할 수 있다. 이러한 문제점을 해결하기 위하여 다양한 콘텐츠가 필요하며, 초기 방향설정을 위하여 한류3.0 이라는 시대적 특징을 중심으로 기술하였다.

컴포머(Compomer)와 복합레진의 색조안정성에 대한 비교연구

김희재,김광만,김경남 대한치과기재학회 2000 대한치과재료학회지 Vol.27 No.4

Compomer materials have the advantages of glass-ionomer cements and similar physical properties of composite resins. But there were a few studies about the color stability of compomers. In this study, two commercial compomers, Dyract and F2000, and two composite resins, Estelite and Z100, were used. They were stored in 37℃ water bath for 1 week and in 60℃ water bath for another 1 week and then they were aged with 150k1x xenon lamp for 1 week and another 1 week. The original colors just after light cured as the control color were measured by a spectrophotometer according to the C.I.E. L*a*b* Systems, and the colors stored in 60℃ water bath for 1 week, the colors aged with xenon lamp for 1 week in dry and wet condition, the color aged with xenon lamp for 2 weeks in dry and wet condition, were measured by the same method and compared with the control color. The results were as follows. The □E values of dyract after water bath storage and xenon lamp aging were over 10, and the □E values of F2000 after xenon lamp aging were 3.3-6.35. and the □E values of Z100 after xenon lamp aging were 3.3-5.23, and there were not ? E values of Estelite over 3.3 When the thickness of specimen increased the L*, a*, b* values of all material except Dyract were significantly increased(P<0.05), and Compared with dry condition, the L* values were significantly reduced, and the b* values were significantly increased in wet condition(P<0.05). It was concluded that Dyract compomer was not acceptable for and esthetic restorative material in permanent teeth for the color changes were over 10, and F2000 compomer had the color stability similar to the Z100 composite resin.

한국과 일본 대학생의 국민정체성과 다문화태도

김희재,김현숙 동북아시아문화학회 2012 동북아 문화연구 Vol.1 No.33

<P>&nbsp;&nbsp;This paper explores the national identity and the attitudes towards immigrants among Korean and Japanese university students(below, KUS, JUS). In order to this research, we used cross-national comparable data from Korea and Japan researched at the institute for social Science Research in PNU. and analyzed by factor analysis, t-test. The results are as follows. First, the national identity was examined by national attachment, national pride, qualification of nation. In the national attachment and the national pride, JUS was generally higher than KUS. And the qualification of nation of KUS divided by two factors, that is, civic and ethnic factor, whereas that of JUS had not divide. But there seemed that KUS had strong civic identity and JUS had strong ethnic identity. Second, the attitudes towards immigrants was examined by social distance, attitudes about multicultural society, perceived threat. In the social distance, KUS were generally similar JUS, but JUS were more acceptable than KUS for international marriage. In the attitudes about multicultural society, KUS were very similar JUS, but KUS recognized positively and JUS recognized negatively. In the perceived threat, KUS concerned than JUS about taking jobs away from immigrants, damage of lineage and culture, and JUS concerned than KUS about increase of social problems related immigrants. In the attitudes of multicultural policy, KUS were more higher than JUS to support foreign school, wheres JUS were higher than KUS to qualify foreigners as voter.</P>

대설 대응의 제도적 개선을 위한 중요도 분석

김희재,윤상훈,박근오,김근영 한국재난정보학회 2017 한국재난정보학회 논문집 Vol.13 No.3

This study deducted institutional improvement factors for respond of heavy snowfall disaster and performed AHP analysis for choosing the priority. The result of Analysis, establishment of plan concerned heavy snowfall respond was represented most important factor(Importance : 0.461), this is meaningful establishment of plan is more important than facilities, sources, policies for building system of heavy snowfall respond. Establishment of plan concerned respond was represented most important element(Comprehensive Importance : 0.175) in plan for heavy snowfall respond, it is suggested that establishment of respond plan of heavy snowfall has to need for improving law and institution about heavy snowfall. The result of this study will be useful when the central or local government establish institutional improvement plan for respond of heavy snowfall disaster. 본 연구는 대설재난 대응을 위한 제도적 개선요인을 도출하고 주요 우선순위를 선정하기 위해 AHP분석을 수행하였다. 그 결과, 대설대응관련 계획수립이 중요도 0.461로 가장 중요한 것으로 나타났다. 이는 대설대응체계 구축을 위해서는 시설, 자원, 정책보다 계획의 수립이 더 중요하다는 것을 의미한다. 대설대응을 위한 계획 중에서도 대응과 관련된 계획 수립이 종합중요도 0.175로 다른 개선요소에 비해 가장 우선적으로 선행되어야 한다고 도출되었다. 이것은 대설관련 계획 중 경감 및 예방, 대비, 대응, 복구계획 중에서 대응측면을 가장 중요하게 생각하는 것으로 대설과 관련된 법제도 개선시 가장 필요하다는 것을 시사해주고 있다. 본 연구결과는 향후 대선재난 대응을 위한 제도적 개선방안 수립시 기초자료로 활용할 수 있을 것이다.

우리나라 주력산업 고용 성장 결정요인 분석

김희재,김근영 한국도시행정학회 2019 도시 행정 학보 Vol.32 No.2

The purpose of this study was to analyze the factors affecting the growth of employment in the nation's major industries, with major conglomerate playing an important role in the nation's key industries. To this end, the employment data related to the main industry was established for 229 local governments nationwide between 2010 and 2018 and the factors determining employment growth for each major industry were analyzed using multiple return analysis. Summing up the analysis results, first, the growth of employment in the nation's key industries has been affected by the employment of major conglomerate, the number of employees in industrial complexes, the number of employees in manufacturing, the net number of mobile workers and the number of universities. Second, the increase in employment of major conglomerate in the automobile, shipbuilding, petrochemical, display and food and beverage industries among the key industries has been confirmed to have a positive impact on the overall employment of the key industries in each industry. Third, employment growth in the automobile, shipbuilding, petrochemical and information and communication equipment industries was linked to increased employment at industrial complexes in the region, the report showed. Fourth, employment in heavy industries such as related machinery and steel industries was found to be affected by the structural characteristics of the population. 본 연구는 우리나라 주력산업에서 중요한 역할을 수행하고 있는 대규모 기업집단을 중심으로 대규모 기업집단의 고용이 우리나라 주력산업 고용 성장에 미치는 요인을 분석하는 것을 목적으로 하였다. 이를 위해 2010~2018년의 전국 229개 지자체를 대상으로 주력산업과 관련된 고용 데이터를 구축하고, 각 주력산업 별 고용 성장 결정 요인을 다중회귀분석을 이용하여 분석하였다. 분석결과를 요약하면, 첫째, 우리나라 주력산업 고용의 성장에는 대규모 기업집단의 고용, 산업단지 고용자수, 제조업 고용자수, 순 이동자 수, 대학 수 등이 영향을 주고 있는 것으로 나타났다. 둘째, 주력산업 중 자동차, 조선, 석유화학, 디스플레이, 음식료 업종의 대규모 기업집단의 고용 증가는 각 업종의 주력산업 전체 고용에 긍정적인 영향을 주고 있는 것으로 확인되었다. 셋째, 자동차, 조선, 석유화학, 정보통신기기 업종의 고용 성장은 지역의 산업단지 고용 증가와 관련이 있는 것으로 나타났다. 넷째, 관련기계, 철강 업종과 같은 중공업 업종의 고용은 인구 구조적 특성에 영향을 받는 것으로 확인되었다.

사각 신호 교차로의 교통사고 심각도 예측모형 개발 및 분석에 관한 연구

김희재,박태훈(Park, Tae-Hun),박제진(Park, Je-Jin),하태준(Ha, Tae-Jun) 대한교통학회 2009 대한교통학회 학술대회지 Vol.61 No.-

중국동북삼성특집 : 중국 연길시의 발전상황 및 투자환경 분석

김희재 건국대학교 중국문제연구소 1993 중국연구 Vol.12 No.-

Effect of Whole Body Horizontal Vibration Exercise in Chronic Low Back Pain Patients: Vertical Versus Horizontal Vibration Exercise

김희재,권범선,박진우,이호준,남기연,박태준,조용진,김태연 대한재활의학회 2018 Annals of Rehabilitation Medicine Vol.42 No.6

Objective To elucidate the effect of a 12-week horizontal vibration exercise (HVE) in chronic low back pain (CLBP) patients as compared to vertical vibration exercise (VVE). Methods Twenty-eight CLBP patients were randomly assigned to either the HVE or VVE group. All participants performed the exercise for 30 minutes each day, three times a week, for a total of 12 weeks. Altered pain and functional ability were evaluated using the visual analog scale (VAS) and Oswestry Disability Index (ODI), respectively. Changes in lumbar muscle strength, transverse abdominis (TrA) and multifidus muscle thicknesses, and standing balance were measured using an isokinetic dynamometer, ultrasonography, and balance parameters, respectively. These assessments were evaluated prior to treatment, 6 weeks and 12 weeks after the first treatment, and 4 weeks after the end of treatment (that is, 16 weeks after the first treatment). Results According to the repeated-measures analysis of variance, there were significant improvements with time on VAS, ODI, standing balance score, lumbar flexor, and extensor muscle strength (all p<0.001 in both groups) without any significant changes in TrA (p=0.153 in HVE, p=0.561 in VVE group) or multifidus (p=0.737 in HVE, p=0.380 in VVE group) muscle thickness. Further, there were no significant differences between groups according to time in any of the assessments. No adverse events were noticed during treatment in either group. Conclusion HVE is as effective as VVE in reducing pain, strengthening the lumbar muscle, and improving the balance and functional abilities of CLBP patients. Vibrational exercise increases muscle strength without inducing muscle hypertrophy.

Comparative Studies of the Reliability Estimation for a Circular Consecutive-r-out-of-k: F System with Exponential Lifetime

김희재,원호연,문영길 한국자료분석학회 2004 Journal of the Korean Data Analysis Society Vol.6 No.3

We shall propose maximum likelihood, Bayesian and generalized maximum likelihood estimation for the reliability of a circular consecutive-r-out-of-k: F system with exponential lifetime distribution. Each estimation will be compared numerically in the terms of various mission times, parameter values and asymptotic relative efficiency for maximum likelihood estimator through Monte Carlo simulation.