• 제목/요약/키워드: the end of Chosun

검색결과 258건 처리시간 0.029초

석회석 미분말을 혼합한 시멘트 경화체의 내구성능 평가 (Evaluation of Durability of Cement Matrix Replaced with Limestone Powder)

  • 장우식;박광필
    • 한국건설순환자원학회논문집
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    • 제12권1호
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    • pp.102-109
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    • 2024
  • 석회석미분말을 콘크리트용 재료로 활용하기 위하여 치환율을 달리하여 제조한 시멘트 경화체의 역학적 특성 및 내구특성을 평가하였다. 일반적으로 석회석미분말은 시멘트 수화반응에 기여하지 못함으로 이를 사용한 모르타르의 압축강도 시험결과 치환율이 증가할수록 압축강도는 감소하였다. 그러나 석회석미분말을 사용한 모르타르의 염소이온 침투저항성, 탄산화저항성 및 화학저항성 등 내구성능을 평가한 결과 석회석미분말의 작은 입자가 시멘트 경화체 내부의 미세한 공극을 채워주는 마이크로 필러효과로 인하여 치환하지 않은 기준 모르타르에 비하여 우수한 결과를 나타내었다. 따라서 석회석미분말은 콘크리트의 내구성 향상을 위한 효과적인 방법으로 활용될 수 있을 것으로 기대된다. 본 연구에서는 석회석미분말의 치환량을 0 %, 5 %, 10 %, 15 %로 변화시켜 내구성능을 평가하였으나 향후 석회석미분말의 종료와 치환량을 다양한 수준으로 변화시켜 내구성능에 미치는 영향을 보다 자세히 연구할 필요가 있을 것으로 판단된다.

지능정보사회 노인층의 디지털 정보격차와 과제 (The Digital Divide and Challenges on the Elderly in Intelligence Information Society)

  • 박노민
    • 디지털정책학회지
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    • 제3권1호
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    • pp.11-20
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    • 2024
  • 시대적 디지털 환경변화를 반영하는 지능정보사회는 개인적인 삶의 변화 가능성으로 기대되는 반면, 지능정보기술에 익숙하지 않은 정보취약계층의 디지털 격차는 활용 불가능의 불편함을 넘어 지능정보사회에서 누릴 수 있는 사회적·경제적 불평등이 야기되는 현실이다. 본 연구는 지능정보사회의 디지털 포용 실현을 위한 노인 미디어교육 분야의 과제를 도출하는 데 목적이 있다. 이를 위해 '제6차 국가정보화 기본계획(2018~2022)'과 '2022 교육정보화백서(2022)'를 통해 지능정보사회와 관련되는 국가정보화 비전, 목표, 전략 및 과제를 살펴보았으며, '2022년 디지털 정보격차 실태조사' 결과를 통해 취약계층으로 분류된 노인층의 디지털 격차 현황을 통하여 디지털정보화 역량(54.5%)과 디지털 정보화 활용수준(72.6%)은 낮은 것으로 파악하였다. 지능정보사회에서 노인층의 디지털 정보격차를 완화하기 위해서 노인 미디어교육 분야에서는 지능정보기술을 활용한 지능형 미디어교육 서비스 개발, 늘배움 온라인서비스 채널을 통한 노인 미디어교육 서비스 제공, 노인층을 위한 디지털 지능형 미디어 교육 지원 등이 필요할 것으로 여겨진다.

마이크로중력환경에서 사용 가능한 관성저울의 성능평가 (Performance Evaluation of Inertial Balance for Measuring Mass in Microgravity)

  • 장현진;이주희;최재혁;박설현
    • 대한기계학회논문집A
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    • 제38권12호
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    • pp.1395-1401
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    • 2014
  • 중력이 거의 작용하지 않는 마이크로중력환경에서 소동물의 질량이 측정 가능한 고성능 관성저울을 개발하기 위해, 약 100g의 측정시료를 이용하여 관성저울의 핵심 디자인 파라미터인 로드셀의 응답특성을 평가하였다. 정확한 성능평가를 위해서 1.5초의 마이크로중력환경을 제공할 수 있는 15m 자유 낙하탑을 활용하였으며, 살아 있는 동물의 질량을 측정해야 하는 점을 고려하여 측정시료의 감속 크기 변화에 따른 로드셀의 응답특성를 파악하였다. 동일한 가속도로 가 감속되는 표준시료와 측정시료의 관성력 비의 분석결과 로드셀이 장착된 가속판이 평균 이동속도 0.5 m/s 이상으로 운동하는 경우에 한하여 설계 기준에 부합하는 것을 알 수 있었다.

적층각이 다른 CFRP/Al 혼성 원형부재의 충돌안전성능 평가 (Evaluation to Collision Safety Performance of Stacking Angle Different CFRP/Al Circular Member)

  • 양용준;김영남;차천석;정종안;양인영
    • 한국안전학회지
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    • 제30권6호
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    • pp.1-6
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    • 2015
  • The actual condition is that environmental pollution due to the development of various industries has recently become a serious issue. An interest in improving the gas mileage is rising due to an increase in the number of vehicles in the era of high oil price in particular. In order to solve this problem, priority should be given to light-weight design of car body, However, at present, a design method enabling the conventional steel plate to be replaced is direly needed in order to guarantee passengers' safety according to excessive light-weight design of car body. In this study, in order to apply a design method that could realize fuel savings and environmental pollution prevention through an improvement in gas mileage together with meeting the safety requirements for vehicles, it was supposed that CFRP/Al composites member would be used as primary structural member. And to this end, it was intended to obtain optimum design data by experimentally implementing external impulsive load applied to the car body. According to results of impact test of CFRP/Al composites member, a collapsed shape of folding, crack, and bending occurred. So, it was possible to find that energy was observed. And in case of specimen having an angle of $90^{\circ}$ in the outermost layer and stack sequence of $[90^{\circ}{_2}/0^{\circ}2]s$, its collapsed length was shown to be short. Therefore, it was possible to find that the absorbed energy was shown to be higher by 20% or above at the maximum.

화재모델링을 이용한 목표 대상물의 열적 손상에 대한 정량적 위험성 평가방법의 고찰 (An Investigation of Quantitative Risk Assessment Methods for the Thermal Failure in Targets using Fire Modeling)

  • 양호동;한호식;황철홍;김성찬
    • 한국화재소방학회논문지
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    • 제30권5호
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    • pp.116-123
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    • 2016
  • 화재모델링을 이용한 목표 대상물의 열적 손상에 대한 정량적 위험성 평가방법이 검토되었다. 이를 위해 대표적인 화재모델로서 FDS가 사용되었으며, 특정 구획 내에서 화원 면적 변화에 따른 전기 케이블의 열적 손상과 관련된 확률이 평가되었다. 보수적 관점에서 적용되고 있는 '최대 손상임계 초과확률'과 손상시간의 정보가 포함된 '손상확률'이 체계적으로 비교되었다. 목표 대상물이 표면온도 및 열유속에 대한 최소 손상기준에 도달하는 순간에 열적 손상이 발생된다는 가정이 적용된 최대 손상임계 초과확률에 비해 본 연구에서 제안된 손상확률은 정량적 화재 위험성을 보다 현실적으로 평가할 수 있음을 확인하였다.

함라마을 부농주거의 건축특성 연구 (The Study on the Architectural Characteristics of the Wealthy Farmhouses in Ham-Ra)

  • 유은미;홍승재
    • 한국주거학회논문집
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    • 제17권6호
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    • pp.99-108
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    • 2006
  • Ham-ra is a village that belongs to Ham-yuel Ri, Ik-san city and also known as the village where 4 millionaire modem age rich farmer households are residing in the center of the village. Originally, central point of the village was Gaeksa and Hyanggyo that is in Suodong, but early 1900s, rich farmers found new Places beside Suodong and built large-scale houses and around it, houses of tenant and commercial places were formed and became the new center of the village. Therefore, Ham-ra village shows well about the changes of the traditional village in the end of Chosun Dynasty aspect that of existent village space according to rich farmer's growth. Especially, the large scaled Korean traditional houses which were built newly in the year between 1917 to 1939 shows main road and Natural stream surrounding the village which are not found in any other village. 3 rich farmers (Lee Bae-won, Jo Hae-young, Kim An-gyun house) and Lee Jib-cheon's houses built a large scaled Sarang-chae and An-chae to compete and to show off there wealth. This residing imitated High-classe house yet accommodated social changes and through a voluntary experiment, is expressing modernity of Han-ok very well. Similarity and creativity in residing form appears well in buildings similar time and village. This research analyzed space composition change of the village and characteristic of Architecture who appear at modern process of typical farmer houses which make a strong resolution to Ham-ra hereupon.

대학수학능력시험 수학 영역의 변화를 통해 살펴본 고등학교 수학 평가의 방향 탐색 (Exploring the direction of Assessment in Korean High School Mathematics through College Scholastic Ability Test Mathematics Domain Changes)

  • 최인선;이세형;문두열
    • 한국학교수학회논문집
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    • 제26권2호
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    • pp.137-158
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    • 2023
  • 본 연구는 1993년부터 시행된 대학수학능력시험 수학 영역의 변화를 살펴봄으로써 향후 수학 영역 체제의 개선 방향을 탐색하고 우리나라 고등학교 수학교육에서의 평가 방향 정립을 위한 시사점을 도출하고자 하였다. 이를 위해, 대학수학능력시험 수학 영역을 시험 체제, 내용 영역, 행동 영역을 중심으로 분석하고 다음과 같은 결과를 얻었다. 첫째, 시험 체제는 시험 시간, 문항 수 외에 평가 요소와 문항 유형 등에도 영향을 미쳤음을 확인하였다. 둘째, 내용 영역 분석을 통하여 교육과정과 평가 영역의 관계성을 확인하고, 평가 영역 설정의 중요성을 확인하였다. 셋째, 행동 영역 분석을 통하여 특정 행동 영역에서 문항 유형의 고착화 가능성을 확인하고, 평가 문항의 유형에 대한 지속적 변화의 필요성을 확인하였다. 이를 바탕으로 대학수학능력시험 수학 영역에서의 시대적 요구와 변화를 반영할 수 있는 평가의 방향과 그에 따른 제반 사항에 대하여 논의하였다.

공학계열 대학생의 학습역량 측정도구 개발 및 타당화 연구: K대학을 중심으로 (A Study on the Development and Validation of the Learning Competencies Scale for Engineering College Students: A Case Study K University)

  • 김나영;강동희
    • 공학교육연구
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    • 제25권4호
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    • pp.21-34
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    • 2022
  • This study is conducted with the aim of identify the factors constituting learning competencies for engineering college students, and developing and validating the scale to measure them. To this end, literature and prior research were reviewed and focus group interview was conducted with high-achieving learners of K University in the capital region of Korea. According to previous research, 3 learning competency groups, 12 learning competencies and 41 sub-competencies were derived. Delphi survey was carried out twice, 28 sub-competencies were derived among the 41 sub-competencies through this process. 166 initial items were developed through literature review and FGI. Then, 130 items were confirmed by verifying content validity in the second Delphi survey. Based on this, pilot test were performed with 110 students in K university, and an interview was conducted with 50 students who participated in the pilot test. Reflecting the pilot test results, 1 sub-competency and 22 items were deleted. After the confirmed pilot test results, the main test were performed with all current students in K University. According to the main test result, the validity of the scale and the model fit was verified for the response data of 823 students, and the scale consisting of a total of 105 items was confirmed. The final learning competencies scale included three competency groups and 10 learning competencies. The scale developed in this study can be used as an independent scale for each competency group as needed. It is expected that this scale can be contributed to support the development their learning competencies for academic success of engineering college students, who are future learners.

Utilizing Advanced Pad Conditioning and Pad Motion in WCMP

  • Kim, Sang-Yong;Chung, Hun-Sang;Park, Min-Woo;Kim, Chang-Il;Chang, Eui-Goo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.171-175
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    • 2001
  • Chemical mechanical polishing(CMP) process has been widely used to planarize dielectrics and metal, which can apply to employed in integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of free-defects in inter level dielectrics and metal. Especially, defects like (micro-scratch) lead to severe circuit failure, and affects yield. Current conditioning method - bladder type, orbital pad motion - usually provides unsuitable pad profile during ex-situ conditioning near the end of pad life. Since much of the pad wear occurs by the mechanism of bladder tripe conditioning and its orbital motion without rotation, we need to implement new ex-situ conditioner which can prevent abnormal regional force on pad caused by bladder-type and also need to rotate the pad during conditioning. Another important study of ADPC is related to the orbital scratch of which source is assumed as diamond grit dropped from the strip during ex-situ conditioning. Scratch from diamond grit damaged wafer severely so usual1y scraped. Figure 1 shows the typical shape of scratch damaged from diamond. We suspected that intensive forces to the edge area of bladder type stripper accelerated the drop of Diamond grit during conditioning, so new designed Flat stripper was introduced.

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조선후기 입영(笠纓)에 대한 연구 (A Study on 'Ibyeong' in the Late Joseon Dynasty)

  • 장숙환
    • 한국의상디자인학회지
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    • 제11권1호
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    • pp.1-16
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    • 2009
  • Ip-yeong or gat-keun decorate heuk-rip, supplementing its simplicity. When the wind blew, a dynamic beauty was created, especially if the gat-keun was made with long straps of jade or silk. Basically, ip-yeong was a practical chin strap to hold the gat tight on the head. Commoners made ip-yeong by folding cotton cloth or fine gauze. However, as available materials became diversified, people used cloth, jade, agate, amber, coral, gold medallion, rock crystal and bamboo as well, juk-yeong, which was made with bamboo, became popular especially when Heungsun Daewon-gun, the father of King Kojong, decreed that people wear simple clothes. Most records concerning ip-yeong in Chosun-wangjo-shillok, the authentic record of the Joseon Dynasty, are related to forbidding a sumptuous life. The book also suggests that ip-yeong was bestowed by the king or was offered to foreign diplomats as gifts. Ip-yeong doesn't seem to be a unique system for Korea. Based on portraits or paintings where ip-yeong can be found, it seems to have been widely used during the Yuan dynasty and the Goryeo dynasty. The system disappeared in China as the Ming Dynasty was established, but it remained in use in the Korean Goryeo dynasty and through the Joseon. Literature suggests that the same materials were used for ip-yeong from the beginning of Joseon to the end of the dynasty. Guyeongja refers to a ring that connects an ipja to a chin strap. Guyeongja made with silver, bronze and jade still remain. In gungjungbalgi, the royal court inventory book, records of imogarye can be found (1882), where ten pairs of pure gold strap rings and ten pairs of gold-plated ones were used for a royal wedding.

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