• 대한조선학회논문집
• /
• 제51권3호
• /
• pp.254-258
• /
• 2014

Field trial in ice-covered sea is one of the most important tasks in the design of icebreaking ships. To correctly estimate ice load and ice resistance on ship's hull, It is essential to understand the material properties of sea ice during ice field trials and to perform the proper experimental procedure by gathering sea ice data. A measurement of sea ice properties was conducted during February and March of 2012 with the Korean Icebreaking research vessel "ARAON" in the Amundsen Sea, Antarctica. This paper describes a test procedure to obtain sea ice data which provide basic information to estimate ice loads and icebreaking performance of the ship. The data gathered from sea ice field trials during the 2012 Antarctic voyage of the ARAON includes ice temperature/salinity/density and the compressive/flexural strength of sea ice. This paper analyses the gathered Antarctic sea ice material properties comparing with the previous data obtained during ARAON's Arctic and Antarctic voyages in 2010.

• 대한자기공명의과학회:학술대회논문집
• /
• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
• /
• pp.109-111
• /
• 2003

Compared to the present clinical field strengths, MR at 47 and above promises to improve anatomic imaging quality by factors, and to bring metabolic and functional imaging to the forefront of research and diagnostic modalities. While human bore sized magnets as high as 9.4T are now installed, realization of the potential benefit of these magnets will require more of the MR system than a simple field, frequency or power scaling from technologies used at lower fields. New constraints on the high field MR studies, both physical and physiological, will require new technical developments to be considered for the highest field systems.

• 한국수학교육학회지시리즈D:수학교육연구
• /
• 제12권4호
• /
• pp.293-299
• /
• 2008

Young children have manifold potentialities. As any teacher or parent knows, a child's most obvious strengths contribute to their development in unexpected ways. A sporting or musical forte may provide an invaluable youthful opportunity to experience "the pursuit of excellence," but may then be laid aside. It is exceedingly rare for a strength which informed observers might "identify" at school level to develop in a predictable way. Most strengths blossom and are then laid aside, whilst some evolve sideways (for example, when the inner muse shies away from the required level of commitment, or takes fright at the miniscule prospects of success in the given field). In their place other strengths-which one may have noticed, but which were never "diagnosed" in the same way-take over and flourish.

• 한국정보시스템학회지:정보시스템연구
• /
• 제16권2호
• /
• pp.93-122
• /
• 2007

RFID has fundamental influences on today's business management. This research seeks to formulate the opportunities and challenges, the strengths and weaknesses and the perceived benefits of RFID implementation in three industries: manufacturing, medical-service, and distribution. Ten companies of successful RFID deployment in Korea are presented. Field interview and panel discussion were used to explore the research purpose. The core challenges include RFID readability issues, lack of best practices, increasing prime cost, visible ROI, implementation cost, and employee's resistance. The strengths include IT infrastructure, system integration competency, RFID business model creation ability, executive's support. There is little weakness in Korea companies, there are many perceived benefits in three industries. The most distinctive finding is that the visible ROI was found out in the manufacturing industry, not in the distribution industry. The opportunities and challenges, the strengths and weaknesses and the perceived benefits are some different in three industries, which provide valuable guidance for Korean companies in seeking the RFID opportunities. This case study represents a pioneer research of RFID adoption in Korea.

• Journal of Electrical Engineering and information Science
• /
• 제3권3호
• /
• pp.385-390
• /
• 1998

In this paper, the oscillator strengths of both the heavy-hole and the light-hole excitons in GaAs-A\ulcornerGa\ulcornerAs and In\ulcornerGa\ulcornerAs-InP quantum wells with the effect of a magnetic field applied along the growth axis are studied. The calculation is carried out usig a variational approach, based on a simple trial exction wave function. The exciton oscillator strengths are found to decrease with increasing well width and to increase with the applied magnetic fields which lead to additional quantum confinement for moderately wide well sizes. Also, the oscillator strengths for the heavy-hole exciton are found to be large than those of the light-hole exciton in these quantum well structures.

• Computers and Concrete
• /
• 제25권1호
• /
• pp.83-94
• /
• 2020

The use of fly ash in modern-day concrete technology aiming sustainable constructions is on rapid rise. Fly ash, a spinoff from coal calcined thermal power plants with pozzolanic properties is used for cement replacement in concrete. Fly ash concrete is cost effective, which modifies and improves the fresh and hardened properties of concrete and additionally addresses the disposal and storage issues of fly ash. Soft computing techniques have gained attention in the civil engineering field which addresses the drawbacks of classical experimental and computational methods of determining the concrete compressive strength with varying percentages of fly ash. In this study, models based on soft computing techniques employed for the prediction of the compressive strengths of fly ash concrete are collected from literature. They are classified in a categorical way of concrete strengths such as control concrete, high strength concrete, high performance concrete, self-compacting concrete, and other concretes pertaining to the soft computing techniques usage. The performance of models in terms of statistical measures such as mean square error, root mean square error, coefficient of correlation, etc. has shown that soft computing techniques have potential applications for predicting the fly ash concrete compressive strengths.

• International Journal of Concrete Structures and Materials
• /
• 제10권1호
• /
• pp.47-60
• /
• 2016

The objective of this study was to evaluate the capability of different strength-maturity models to account for the effect of the hydration heat on the in-place strength development of high-strength concrete specifically developed for nuclear facility structures under various ambient curing temperatures. To simulate the primary containment-vessel of a nuclear reactor, three 1200-mm-thick wall specimens were prepared and stored under isothermal conditions of approximately $5^{\circ}C$ (cold temperature), $20^{\circ}C$ (reference temperature), and $35^{\circ}C$ (hot temperature). The in situ compressive strengths of the mock-up walls were measured using cores drilled from the walls and compared with strengths estimated from various strength-maturity models considering the internal temperature rise owing to the hydration heat. The test results showed the initial apparent activation energies at the hardening phase were approximately 2 times higher than the apparent activation energies until the final setting. The differences between core strengths and field-cured cylinder strengths became more notable at early ages and with the decrease in the ambient curing temperature. The strength-maturity model proposed by Yang provides better reliability in estimating in situ strength of concrete than that of Kim et al. and Pinto and Schindler.

• 대한소아치과학회지
• /
• 제23권2호
• /
• pp.347-355
• /
• 1996

The purpose of this study was to compare the bond strengths of different kinds of glass ionomer cements (GIC), which is recently increasing the clinical application in the field of pediatric dentistry and measure the repaired bond strengths in order to examine the clinical applicabilty of partial repaired cases. By using one kind of the light cured type GIC and three kinds of the chemical cured type GIC, the bond strengths of the followings were compared : unrepaired group as control, repaired conditioning group, which was treated the repaired surface using 25% polyacrylic acid and repaired non-conditioning group without surface treatment. Three point bending test was performed under Universal Testing Machine in order to measure the compressive bond strengths. The results were as follows : 1. Light cured GIC had higher bond strength than chemical cured type GIC in both of repaired and unrepaired groups. 2. In repaired cases, all of the materials decreased the bond strength when compared to the control group. In the light cured type, the bond strength of repaired conditioning group decreased 31.6%, repaired non-conditioning group decreased 40.8%. In chemical cured types, the bond strength of repaired conditining group decreased 11.8%, repaired non-conditioning group decreased 20.9%. 3. All the materials, in the case of the chemical treatment on the repaired surface using 25% polyacrylic acid had higher bond strength than untreated but, lower than control group.

• 한국도서관정보학회지
• /
• 제40권4호
• /
• pp.243-259
• /
• 2009

이 연구는 경력개발의 핵심주제로 개인강점이론을 소개하면서 강점의 구성요인, 강점의 개성화, 그리고 취업력을 논한다. 개인강점은 취업력에 관건자원이며 단기적 취업과 장기적 경력개발의 핵심적 능력이다. 취업력은 한 개인의 능력상의 강점과 개성에 대한 체계적으로 조직된 정보로서 개인의 직업적 문제해결을 위한 능력의 결정체이며, 이를 적극적으로 인식할 때, 지식기반사회의 전략적 자원이 된다. 이 연구는 취업력을 한 개인이 검증된 자기의 강점으로 일 기회를 찾거나 창조하여 스스로를 고용시키는 능력으로 정의한다. 경력개발과 취업은 취업력 개념을 통해서 가능할 것인데, 사서를 포함한 대학의 모든 학생들에게 적용될 수 있다. 취업력 제고의 과정이 대부분 개인에 내재적 자료와 외부 상황적 자료를 정보화, 지식화하는 것이므로 문헌정보학, 특히 개인정보경영(PIM)과 개인지식경영(PKM)의 측면의, 기여와 지원이 기대되고 있다.

• 한국구조물진단유지관리공학회 논문집
• /
• 제22권2호
• /
• pp.98-104
• /
• 2018

콘크리트 비파괴강도 추정식은 일반적으로 콘크리트 강도를 결정하는데 사용된다. 그러나 기존의 추정식들은 대부분 제한된 실험 변수를 토대로 제안되어 배합조건, 강도특성 등이 다양한 실제 공용중 교량의콘크리트 압축강도 추정시 많은 오류를 포함한다. 본 연구에서는 297개 공용 교량의 정밀안전진단 결과 중 콘크리트 비파괴시험 및 현장 코어강도 시험결과를 토대로 콘크리트 부재의 코어강도와 비파괴 추정강도 평가결과를 비교분석하였다. 분석결과 분석이 이루어진 기존 추정식들 중 일본건축학회 CNDT소위원회 강도계산식이 다른 추정식에 비하여 실제파괴강도와의 오차가 가장적고 상관분석의 신뢰도도 가장높은 것으로 검토되었다. 그러나 이 추정식은 코어강도가 30 MPa이상일때 추정강도는 과소평가되는 것으로 나타났다. 이에 본 논문에서는 추정식에 의한 강도와 현장 코어강도사이의 관계를 활용하여 회귀분석을 통한 개선된 비파괴강도 추정식을 제안하였다.