• Title/Summary/Keyword: See-saw

Search Result 52, Processing Time 0.021 seconds

Field Test and Analysis of Joint Depths and Timing Contraction Joint Sawing for Concrete Pavement (콘크리트포장의 줄눈깊이 및 절단시기에 관한 유도균열 거동특성 연구)

  • 홍승호;양성철;엄주용
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1999.04a
    • /
    • pp.469-474
    • /
    • 1999
  • The object of study is analysis to joint crack behavior of cracked joint concrete pavement. In the new constructing concrete pavement, joint crack behavior was compared general joint depth D/4 with joint depth D/3 and D/5 that it's environmental effects changed temperature and humidity. After joint saw cutting joint section was predicted crack at joint depth D/5 test section from the result for monitoring development of crack. In the setting of data logger system of the joint section, it's data compared see with the naked eye. In the research, development of crack at the joint section should effect to joint saw timing latter than joint depth. This performance could be the minimum of deterioration to the early curing. In this research, At new constructing of joint concrete pavement of highway, the monitoring system be setting after finished paving and joint sawing. The system and see with the naked eye could be analysis to pavement behaviors from collecting data at the test section. This system could be monitoring shot term and long term. In this report, joint section of crack behavior analysis used to collected data during a month after paving and joint sawing.

  • PDF

Explosion Bulge Test Underwater of 800MPa Grade Pre-heat Free Welding Plate (800MPa급 무예열 용접 판재의 수중 폭파변형시험)

  • Park, Tae-Won;Song, Young-Beum;Kim, Jin-Young;Yang, Sung-Ho;Park, Chul-Gyu;Seo, Jun-Suck;Kim, Hee-Jin
    • Journal of Welding and Joining
    • /
    • v.28 no.6
    • /
    • pp.63-69
    • /
    • 2010
  • The pre-heat free consumables for GMAW, SAW and FCAW processes that matche with the Cu-bearing PFS-700 steel which has yield strength over 700MPa were developed and evaluated to see the suitability in military such as submarine and battle ship. Explosion Bulge Test underwater was developed and applied to see the reliability of welded structure. All welding was conducted without pre-heat before welding, the interpass temperature was below $150^{\circ}C$ for all welding conditions. Tensile strength for the weld metal in GMAW, SAW and FCAW process is 887MPa, 875MPa and 813MPa, respectively, these values are similar to the base metal of PFS-700 steel of 838MPa. EBT results in GMAW, SAW and FCAW show 14.0%, 14.02% and 15.9% reduction of thickness without generation of crack, respectively and stand-off distance was set up properly to have over 14.0% reduction of thickness. Through EBT results, the developed new consumables are applicable to the weapon systems such as submarine and battle ship.

Explosion Bulge Test in Underwater of 800MPa Grade Pre-Heat Free Welding Plate (800MPa급 무예열 용접 판재의 수중 폭파변형시험)

  • Park, Tae-Won;Song, Young-Bum;Kim, Jin-Young;Yang, Seong-Ho;Hong, Sung-Suk;Shim, In-Ok;Park, Chul-Kyu;Kim, Hee-Jin
    • Proceedings of the KWS Conference
    • /
    • 2010.05a
    • /
    • pp.63-63
    • /
    • 2010
  • The pre-heat free consumables for GMAW, SAW and FCAW processes that matches the Cu-bearing PFS-700 steel which has yield strength over 700MPa were developed and evaluated to see the suitability in military such as submarine and battle ship. Explosion bulge test in underwater was developed and applied to see the reliability of welded structure. All welding was conducted without pre-heat before welding, the interpass temperature was below $150^{\circ}C$ for all welding conditions. Tensile strength for the weld metal in GMAW, SAW and FCAW process is 887MPa, 875MPa and 813MPa, respectively, these values are similar to the base metal of PFS-700 steel of 838MPa. EBT results in GMAW, SAW and FCAW show 14.0%, 14.02% and 15.9% reduction of thickness without generation of crack, respectively and stand-off distance was set up properly to have over 14.0% reduction of thickness. Through EBT results, the developed new consumables are applicable to the weapon systems such as submarine and battle ship.

  • PDF

Analysis of U.S.-China Relations on The Korean Peninsula Military Puzzle : Under Circumstance of NK's Nuclear, THAAD, US-ROK Alliance (한반도 군사적 현안에 관한 미중관계 고찰 : 북핵, 사드, 한미동맹의 환경 하에서)

  • Woo, Jeongmin
    • Convergence Security Journal
    • /
    • v.17 no.3
    • /
    • pp.83-93
    • /
    • 2017
  • The U.S.-China Relations could be analyzed two perspectives and their basis under major international p olitics theory-power transition with conditions: (1) North Korean's nuclear puzzle, (2) THAAD in the Kor ean Peninsula and (3) the U.S.-ROK Alliance. One perspective is the global order dominates the regional order, and then stable regional order comes out. The other is the regional order dominates the global ord er, and China wages a regional hegemonic conflict against the United States. Consequently, America's o verwhelming leadership in North Korean's nuclear, THAAD and U.S.-ROK Alliance as national power is expected to endure. But China also has expected empowerment and cooperation for the peace and stabilit y on the Korean Peninsula military problems. In this perspective, South Korea needs to pay attention to the changing power distribution and competition between the U.S. and China and needs to strengthen a balancing and harmonious diplomatic strategy, so called 'see-saw diplomacy'.

Effect of Convection on the Solidification Microstructure of Hyper-Peritectic Systems (과포정계 합금의 응고조직에 미치는 대류의 영향)

  • Park, Byeong-Gyu;Kim, Mu-Geun;Park, Jang-Sik;Kim, Geun-O;Choe, Jae-Gwang
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.25 no.7
    • /
    • pp.958-966
    • /
    • 2001
  • This study has examined the microstructural development in the Bridgman type directional solidification of hyper-peritectic Sn-Cd alloys, and the temperature and flow field have been numerically simulated to see if there is any change induced by convection. The directional solidification experiments carried out in quartz tubes with inside diameters of 0.4∼6mm showed that the resulting microstructures are clearly dependent on the size of tube diameters. The bigger ampoules where the effect of convection is highly expected produced saw-like structures resulting from the primary $\alpha$ and peritectic $\beta$ phase growing together at a planar solid-liquid front, with the former being surrounded by the latter. In the smaller ampoules, where the effect of convection is expected low however, the saw structure disappears, and as is understood from the theoretical prediction based on diffusion-controlled solidification the initial growth of the primary $\alpha$ phase is replaced by the nucleation of the peritectic $\beta$ phase whose growth continues to the end of the solidification.

Development of Low Cutting Resistance Drum for Sawdust Machine (톱밥제조기 저부하 드럼개발)

  • 배용환;반갑수
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2002.10a
    • /
    • pp.608-611
    • /
    • 2002
  • We developed low resistance drum that is used in sawdust machine in this research. The existent drum have two dimensional cutting form(orthogonal cutting) when see cutting pattern of saw cutter and wood, cutting resistance is big and cutting power is cost much, and also, vibration happens extremely. To improve this shortcoming, we developed helical type low cutting resistance drum for three dimensional cutting possible, decreased vibration and cutting resistance of sawdust machine, and improve productivity and sawdust ventilation. Also, a developed drum is mounting in sawdust machine, it is sold by product.

  • PDF

Raman Spectroscopy of the Solid Solution Limit in $Li_{1-X}Al_{2X}Ta_{1-X}O_3$ System (Raman 분광법을 이용한 $Li_{1-X}Al_{2X}Ta_{1-X}O_3$ 고용한계 분석)

  • Kim, Chong-Don;Hong, Kug-Sun;Joo, Gi-Tae
    • Analytical Science and Technology
    • /
    • v.5 no.1
    • /
    • pp.115-120
    • /
    • 1992
  • The upper limit of solid solution of $Al_2O_3$ in $LiTaO_3$ was investigated using X-ray diffraction and Raman spectroscopy. By substituting cations in $LiTaO_3$ with $Al^{3+}$, the melting temperature was lowed and the ferroelectric properties can be improved. It is easier at lower temperature to fabricate the single crystal used for SAW filters and IR sensors. From the measured lattice constants and Raman band broadening, the solubility limit was X=0.25mol in $Li_{1-X}Al_{2X}Ta{1-X}O_3$, above which $Al_2O_3$ was obsered as a second phase. The Raman band of sintered $LiTaO_3$ was compared with that of the single crystal to see the effect of grain size on the band broadening.

  • PDF

A qualitative analysis on therapeutic factors in group counseling based on family sculpture technique (질석 분석을 통한 가족조각 기법 집단상담의 상담효과 요인)

  • 김수연;심혜숙
    • Journal of Families and Better Life
    • /
    • v.19 no.5
    • /
    • pp.239-258
    • /
    • 2001
  • The purposes of this study are first, to develop the group counseling program based on Satir’s family sculpture technique, second to investigate the therapeutic factors of Satir’s family sculpture in group counseling. To perform this study, 8 session of time limited(3 hours) group counseling were carried out. There were 12 participants in this group. The major findings were as follows: 1) the rank order fro therapeutic factors were university, group cohesiveness, instillation of hope, family reenactment, self-understanding and altruism. 2) through the family sculpture technique, group participants saw their communication patterns. They found out that use communication patterns to hide their low self-esteem. They learned the alternative communication style. 3) the participants developed the sense of self-disclosure, empathy and trust in the group. Self disclosure, empathy and trust facilitated a deeper level of therapeutic group interaction. 4) in observing their group members do their family sculpture, participants found out that every family has some problem that the family conflict is universal thing, 5) the participants had opportunity to share their feelings that were hidden deep inside Intensive emotions following self disclosure led to catharsis, 6) the participants developed a good feeling toward their group and it led to group cohesiveness. 7) through the family sculpture technique, the participants gained a better understanding on their role and position within their families 8) through the family sculpture technique, they gained a better understanding of their family. They found their family members’ psychological positions and unfinished emotional businesses and thus they could restructure their family sculptures. 9) the participants had the opportunity to feel what it is like to become parents themselves, They became to see their parents as individuals. 10) the participants acted out what they wanted to do but could not do in the past. They saw the possibility of change and development in themselves.

  • PDF

Strengthening of Advanced Beginner's Nursing Competence through Concept Mapping: Focus Groups (개념지도 교육방법을 이용한 진전된 초보자의 간호역량강화: 포커스그룹)

  • Jang, Ae Ri;Jang, Keum Seong
    • Korean Journal of Occupational Health Nursing
    • /
    • v.24 no.1
    • /
    • pp.1-10
    • /
    • 2015
  • Purpose: This study was to evaluate the strengthening process of advanced beginner's nursing competence through the concept mapping methods. Methods: This study was conducted with focus group study for 1 month from November to December 2012 (n=5). Data were analyzed through open coding, axial coding and selection coding stage. Results: Advanced beginner to represent the experience of nursing empowerment and the three categories of the nine concepts were derived. The first category is 'able to see the entire search.' This concept is to start a search query, the search process of thinking, behavior change is expected. The second category is 'behavior change through the acquisition of knowledge.', and this concept is the embodiment of knowledge, confidence rising, and action changing. The third category is 'nursing empowerment', the aesthetic, ethical, and personal knowledge acquisition, as well as self-growth. Conclusion: Advanced beginner saw the full flow through the concept mapping and obtained knowledge, and changed behavior. Thus, the concept mapping is effective to strengthen the nursing competence.

A World Tour of the Museum of Dentistry (세계 치과 박물관 여행)

  • Kweon, Hoon
    • The Journal of the Korean dental association
    • /
    • v.58 no.4
    • /
    • pp.222-250
    • /
    • 2020
  • Although museums of dentistry and dental museums are both museums related to dentistry, they may differ significantly in the scope and the content regarding the audiences. Museums of dentistry, which display a variety of dental instruments, materials, and photographs, help you learn about the development of dentistry and primarily attract a lot of attention from those who work in dental fields. These museums, however, don't get much attention from the general public. The dental museum, which displays everything related to teeth and dental care, can attract a lot of curiosity and attention not only by those in dental fields, but also by the general public. Dental museums should purpose public health education; they should not just be a place for looking around. This is because the experience of the dental museum has the power to engage people. Therefore, if you add educational functions to the dental museum and make it a place to learn about dental history and oral health care, it can be the institution where culture and health are combined. We need to study history to better understand which improvements we have made and also to see what we need to aim for in the future. The purpose of this study is to examine the actual way each of 28 dental museums in 7 different countries is operated by describing what I saw when I visited them. In addition, the current state of museums of dentistry in Korea is examined and the future development directions is also considered.

  • PDF