• Korean Journal of Materials Research
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• v.8 no.12
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• pp.1138-1145
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• 1998

The sliding wear behavior of Ni-base hardfacing alloy, Deloro 50, was investigated at the contact stresses of 15ksi and 30ksi under the various wear environments. In air at room temperature, Deloro 50 showed lower wear resistance than Stellite 6 even at 15ksi due to the occurrence of severe adhesive wear. This seems to be caused by the lower hardness and work- hardening rate of Deloro 50 than those of Stellite 6. In water at room temperature, Deloro 50 showed as good wear resistance as Stellite 6 at 15ksi. It was considered to be due to that water could effectively prevent metal to metal contact through contacting asperities. However, Deloro 50 showed severe adhesive wear at 30ksi in water at room temperature. It seems to be that the water could not suppress adhesion wear at 30ksi. At $300^{\circ}C$ in air, Deloro 50 exhibited higher wear resistance than Stellite 6 even at 30ksi. It was considered that the oxide glaze layers formed on wear surface during sliding, effectively prevented direct metal-to-metal contacts.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.87-97
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• 2020

The purpose of this study was to investigate effect of simulation based education using standardized patient for contact precaution infection control for nursing student. This study was conducted by including 67 nursing student A university from October to December 2019. This study was mixed method research design. Knowledge and performance confidence related to multidrug resistant organism(MDRO) infection control were measured using questionnaires pre and post test, analyzed using paired t-test and reflection sheet was analyzed using content analysis method. After intervention, two variables were increased significantly. Results of the content analysis showed there were 39 significant statements, which were classified into 13 categories. These results suggest that education on simulation program using standardized patient for contact precaution infection control is effective strategy to enhance knowledge and performance confidence related to MDRO infection control and practical nursing infection control skill, patient centered care, interprofessional collaboration.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.320-320
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• 1994

Carboxyethylgermanium sesquioxide(Ge-132)를 투여용량(300,600, 900mg/kg)과 투여일을 변화시켜 정상마우스와 cyclophosphamide(CY)로 처리한 마우스에 경구투여한 후, Ge-132가 CY 에 의해 변화된 마우스의 면역기능에 미치는 효과를 실험하였다. SRBC 항원 주사전, 동시 또는 후에 Ge-132를 투여시 SRBC에 대한 적혈구 응집소가와 비장세포의 용혈반 형성세포(PFC)수가 항원 주사일과 관계없이 용량의존적으로 증가되어 체액성 면역반응을 강화시켰으며, 마크로파지의 탐식능도 항진시켰다. 그러나 DNFB에 대한 접촉성 지연형 과민반응은 DNFB 감작일과 투여용량에 관계없이 Ge-132투여로 억제되었다. CY를 투여한 마우스에 Ge-132를 병용 투여한 군이 CY 단독 투여군에 비하여 적혈구 응집소가와 PFC수 및 혈중 탄소입자의 제거율이 현저하게 증가되어, CY로 억제된 체액성 면역반응과 마크로파지의 탐식능이 항진된 것으로 나타났다. DNFB 감작 전 CY 투여로 증폭된 접촉성 지연형 과민반응이 Ge-132 병용투여로 감소되어 CY로 유도된 면역독성 반응에 대한 Ge-132의 저지효과를 시사해 주었다.

• Proceedings of the Korea Database Society Conference
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• 2001.11a
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• pp.582-598
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• 2001

웹과 인터넷 관련 기술의 발달로 전통적인 교육의 한계인 시간과 공간의 제약을 벗어나, 누구나 어느 곳에서나 언제든지 교육을 받을 수 있는 사이버 교육이 많은 관심을 끌기 시작하였다. 우리나라에서도 이미 많은 사이버 대학이 등장하였으나, 이상적인 환경에서 시작한 것은 아니어서 많은 어려움과 불편함이 지적되고 있으며 교육의 효과면에서도 의심이 여지가 있다. 본 논문에서는 사이버 대학에서 강의를 하신 경험이 있는 교수들을 대상으로 사이버 교육의 문제점에 대하여 연구하고자, 교육의 주된 프로세스인 강의전달, 강의자료제작, 학생-교수간의 상호접촉, 학생평가에 대한 설문을 작성하여 이들과 교육 효과간의 회귀분석을 통한 관계 조사와 설문 문항별 빈도분석을 통하여 실태파악을 하였다. 연구결과는 이상적인 사이버 교육 환경을 조성하는데 활용될 수 있으리라 기대된다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.66-67
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• 2011

항로를 횡단하여 건설되는 교량이 증가하고 해상교통의 증가에 비례하여 항로의 혼잡도가 증가하는 만큼 선박과 교량의 충돌우려가 커지고 있다. 선박과 교량의 충돌은 단순 접촉사고가 아닌 재난급 사고의 개연성이 크다. 직접 손괴를 일으키는 큰 충돌이 아니더라도 선박과 교각의 충격진동에 의하여 교량상판이 균형을 잃고 연쇄 붕괴하는 일이 종종 발생하여 많은 인명의 손실이 발생하고 있기 때문이다. 적정 교각 폭, 교각의 시인성 증진을 위한 표지와 등화의 설치 및 점등방법 등의 환경 여건 개선, 충돌방지공의 효과 검토, 교량 통과전 사전 점검사항, 교량 부근에서 선박의 조종성 유지방안, 예선의 효과 연구, 관제기법과 안전규정, 불가피한 충돌이나 접촉의 경우 손실 감소대책과 충돌방지공의 효과 등 다각적인 연구가 필요하다. 면피용 탁상이론을 배제하고 현장실무의 경험을 바탕으로 실효적인 방안을 제시하고자 한다.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.6
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• pp.116-125
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• 2008

In general, fretting is a contact damage process due to micro-slip associated with small amplitude oscillatory movement between two surfaces in contact. Previous studies in fretting fatigue have observed a contact size effect related to contact width. The volume-averaging method of theoretically predicted contact stress fields was required to emulate experimental trends and to predict the observed contact size effects. This contact size effect is captured by the mean values of stresses and strains at the element integration points of FE model and two critical plane models (SWT, FS) in the present paper. It is shown that crack nucleation and fretting fatigue life can be predicted by the FE-based critical plane models.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.481-491
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• 2015

This research has verified the efficacy of character education course in Liberal Art Curriculum in accordance with the objective of K Women's University of which is the 'mind sharing through mindfulness, SMART human resources development'. Most of the content of character education is organized aiming to promote values of "appreciation". The subjects are experimental group and control group, of which are 229. Research methods were t-test of between groups. The effects of the course have shown that the experimental group students were higher on the level of connectedness sub-scale in Gestalt Contact Boundary Scale than those of the control group students(t=2.323, p = .021). Although the 'character education' course increased connectedness, but it no positive effect on mindfulness skill and self-esteem. This results showed that character education course is effective to promote mind sharing and connectedness in part. It was discussed about a way of further refining course contents and the need to reflect educational philosophy of the K Women's University.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.589-600
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• 1998

This study was planned to verify the usefulness of Latin square design method in fatigue tests of cables and to see the axial fatigue behavior of wire ropes being used as hangers in suspension bridges. Three parameters : mean stress, stress range. and specimen length, were adopted for verification. The effects of these parameters are in argument except for stress range. Three classes in each parameter were used. Triple replication was performed in each cell to increase the number of replication (or degree of freedoms). The major cause of fatigue failure was fretting fatigue at trellis contact point. Three chosen parameters were proved to be significant. It was verified that the effect of stress range was in agreement with expectation, but the effect of specimen length was contrary to the expectation. It was also observed that the effect of mean stress depended upon the chosen level. Therefore Latin square design method is effective for verifying the parameters that affect fatigue behaviour under orthogonality conditions.

• Korean Chemical Engineering Research
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• v.45 no.2
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• pp.117-123
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• 2007

The effect of aluminium addition to MCM-41 on product yield and carbon number distribution was investigated in the catalytic cracking of a polymer mixture, LDPE, LLDPE, and EVA copolymer, with a composition similar to that found in real agricultural film wastes. Al-MCM-41 catalyst synthesized by post-synthetic grafting method (Al-MCM-41-P) as well as Al-MCM-41 catalyst synthesized by direct sol-gel (Al-MCM-41-D). The catalytic cracking of polymer mixture was carried out in vapor phase contact as well as in liquid phase contact. The amount of acid sites increased with aluminium addition by post method as well as direct method, which was seemed to be due to Lewis acid sites. In liquid phase catalytic cracking, the yield of light hydrocarbon fraction increased with aluminium addition. The effect of aluminium addition on production of $C_5-C_{12}$ hydrocarbons over Al-MCM-41-P catalysts was greater than that over Al-MCM-41-D catalysts. In the case of vapor phase catalytic cracking, the effect of aluminium addition was smaller than that of liquid phase catalytic cracking. The selectivity to $C_{13}-C_{32}$ hydrocarbons was smaller in vapor phase catalytic cracking.

• Journal of the Korean Professional Engineers Association
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• v.21 no.2
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• pp.1-12
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• 1988