• Journal of Korean Society of Steel Construction
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• v.30 no.2
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• pp.115-126
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• 2018

Internationally representative steel design standards have forbidden or limited the application of high-strength steels to tubular joints, partly because of concerns about their unique material characteristics such as high yield ratio. Most of design standards stipulate that for steels whose yield strengths exceed 355 or 360 MPa, the strength equations cannot be utilized or strength reduction factor below 1.0 should be multiplied. However, the mechanical background behind these limitations is not clear. Experimental testing of high-strength steel CHS (circular hollow section) X-joints recently conducted by the authors also clearly indicated that the current limitations might be unduly conservative. As a continuing work, extensive, test-validated numerical analyses were made to investigate the behavior of high-strength steel CHS X-joint under axial compression. Three steel grades covering ordinary to very high strength steels were considered in the analysis. Again it was found that the high strength penalty to the joint strength in current standards is too severe and needs to be relaxed. The high-strength steel joints under the effects of chord stress generally showed higher strength than the ordinary steel joints and their strengths were conservatively predicted by current standards. It is also emphasized that current format of the CHS X-joint strength equation does not reflect observed behavior and needs to be recast.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.631-645
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• 2002

●정의 정척레일을 연속 용접하여 1개의 레일길이를 200m 이상으로 부설한 레일 ●장대레일화 - 차량 시동/제동하중에 의한 교축방향 수평력 작용 - 기존 : 수평력 배분을 위해 단순교로 시공(레일 이음매) - 현재 : 장대레일화 ● 장점 -유지보수비 절감 -승차감 향상(충격/소음 저감) -고속화 및 운행 안전성 향상 ●단점 -큰 레일 축력(파단/좌굴) -교량부, 급곡선부, 분기부 - 장대레일 종하중(하부구조) (중략)

• 프린팅코리아
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• s.33
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• pp.58-61
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• 2005

출판.인쇄분야가 노동부와 한국산업인력공단(이사장 이동훈)이 국가차원에서 표준화한 국가직업능력표준에 포함됐다. 국가직업능력 표준 개발은 노동부가 지난 2002년 5월 산업인력공단 중앙고용정보원에 국가직업능력표준개발기획단을 구성해 국가직업능력표준 개발현황, 모형설계, 활용방안 연구와 일부 영역의 개발을 위탁함으로써 이뤄졌다. 이를 통해 노동부와 산업인력공단은 2004년에 출판.인쇄, 환경서비스, 마케팅, 기계장치설치 및 유지보수, 건설시공 등 5개 영역(34직종)의 직업능력표준 개발을 완료했고 향후 매년 20~30개 영역을 개발하여 2008년까지 총 100개 영역에 대해 개발한다는 계획이다.

• 월간 기계설비
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• s.239
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• pp.24-25
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• 2010

국토해양부(장관 정종환)는 한국토지주택공사(LH)의 노후 영구임대주택 중 7개 단지, 8,808세대를 대상으로 지난 4월 23일부터 그린홈 시범사업(120억)에 들어갔다. 2025년까지 제로에너지 주택건설을 목표로 한 저탄소 녹색성장을 위한 그린홈 건설추진 사업의 일환으로 지난 해 10월 신규 공동주택(20세대 이상)에 대해 그린홈 건설을 의무화[("친환경 주택 건설기준 및 성능"('09.10월 국토해양부 고시)] 하는 건설기준이 마련되었다. 이에 따라 국토부는 기존주택의 그린홈화를 위해 금년부터 우선적으로 공공부문의 노후화된 영구임대주택을 그린홈 개선 시범사업으로 개보수 시행에 들어간다고 밝혔다.

• 한국도로학회:학술대회논문집
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• 2010.09a
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• pp.321-324
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• 2010

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.32 no.6
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• pp.34-48
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• 2003

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.553-560
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• 2020

In the existing research paper, we developed Mechanical Pressurizing Equipment(MPE) that can apply a certain amount of pressure and found out about improving the bonding strength of repair materials constructed in the repair section, and if pressurized, the bonding strength could be increased. In this study, the pressure of Mechanical Pressurizing Equipment(MPE) was changed to 0, 10, 30, 50, and 80 kPa, and the test was conducted to select effective pressure by measuring the flexural, compressive, and bonding strength of the specimens and deformation of the pressure plate at the age of 3 and 28th days. As a result of the test, 30 kPa was the most efficient pressure for the MPE. After producing the specimen with three types of repair materials with different main components, the bonding strength was measured according to dry and wet conditions, construction site (ceiling, wall and floor), and whether or not pressurized, on the 3rd, 7th, 14th, and 28th, indicating that the repair materials mixed with cellulose fiber was most effective for the MPE.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.751-758
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• 2006

To investigate soil management practices for increasing tree growth in arid regions of China, Xinjiang poplar (Populus alba var. pyramidalis) seedlings were planted in a nursery and windbreak and were treated with fertilizers (nitrogen and phosphorus) and absorbents (artificial; K-SAM and natural: Yuho (Artemisia ordosica)) at Dengkou in Inner Mongolia. Seedling height, diameter at breast height (DBH), biomass, and nitrogen (N) and phosphorus (P) concentrations were measured 1.5 years after the treatments. Soil texture was sandy loam for nursery and clay loam for windbreak, soil pH was 8.78 for nursery and 8.51 for windbreak, and total soil N concentration was 0.06% for nursey and 0.08% for windbreak. [n general, seedling height and DBH increased in the N fertilizer treatment compared to control or other treatments both in nursery and windbreak. Also seedling growth increased after the treatments of artificial and natural absorbents in windbreak. Total above- and belowground biomass increased after the N + P treatment. Foliage N and P concentrations following N and/or P treatments were same in the nursey, however, they significantly increased in the windbreak indicating N deficiency. It appeared that N was a limiting factor for early growth of Xinjiang poplar seedlings and artificial and natural absorbents (K-SAM and Yuho) would be useful to increase seedling growth in the arid region.

• The Journal of the Korea Contents Association
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• v.6 no.12
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• pp.201-215
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• 2006

The purpose of this study is to present a plan to design and utilize effectively useful software program in dealing with Teaching Materials and Tools Management in all infant education institute. This program is called Teaching Materials and Tools Management and it is based on the national kindergarten Curriculum notified by ministry of education. To achieve this goal, all teaching materials should be kept to classify and use easily regardless of their shape, kind, and maker(manufacturer). Teaching materials and tools once used in class should be kept after being repaired, And if it is difficult to repair them, write down detail information about them for any teacher to repair them easily. Teaching materials and tools should classified efficiently after being used and registered to recognize their information at first glance. Teaching materials and tools should be registered with an index to manage curriculum effectively when establishing a year plan.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.11
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• pp.1733-1740
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• 2013

An important factor in education is ensuring reliable quality of education. There are a variety of ways based on criteria to ensure the quality of education. To ensure quality management, attendance is important which is highly reliable rating at the account education of Ministry of Employment and Labor and sevice training of Health Care. In contrast, the service training of health care professionals was consisting of formal attendance management, quality of education has been raised as a problem. Recently developed USN-based attendance management system is effective. But if education is proceed at a large number of small scale in the area of education, cost, portability, systeme management, the reliability of the Trainee's attendance remained as problems to solve. To address these needs, this paper quoted low-cost attendance management system which was desighned and implemented by barcode and PC camera. As a result the actual maintenance training system showed a 98% satisfaction in terms of administrator and 95% satisfaction in terms of Trainee.