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Welding and local heat treatment with a high-power laser for GPa-grade transformation-induced plasticity (TRIP) steel were studied. When the focal length and scan speed were controlled under a fixed laser power, defect-free full penetration conditions were achieved at various heat inputs. The effects of laser heat input on the mechanical properties of the steel were evaluated. The results showed that a softened zone was lowered to 350 HV of hardness by tempered martensite under all laser conditions. As the heat input increased, the zone became wider. When an appropriate heat input of 20-60 mm/J was irradiated, the tensile strength and elongation were improved as compared with the base material. Under these conditions, the softened zone was significantly narrowed by the TRIP effect under tensile stress, and base metal fracture occurred. In addition, the laser increased the hardness in the weld metal and further activated the TRIP effect of the retained austenite. However, at a heat input of 90 J/mm, the TRIP effect was limited in the tensile test due to the wide softened zone and the increased hardness of sub-critical heat affected zone during the laser process. In this study, the effective heat input of the laser formed a full-penetration joint and locally enhanced strength and elongation simultaneously.

이 연구의 목적은 교육대학교 및 사범대학에서 진로교육과 관련하여 운영 중인 강좌에서 다루고 있는 내용을 분석하여 교원 양성기관에서 진로교육 관련 교사교육에 시사점을 도출하는 데 있다. 이 연구의 주된 내용은 ① 초·중등 진로교육 및 초․중등교원 양성기관의 교육과정 현황 분석, ② 교원양성기관에서의 진로교육 내용 영역 도출, ③ 초·중등 교원 양성기관의 진로교육 관련 강좌의 진로교육 내용 분석, ④ 교원 양성기관의 진로교육 관련 교사교육에 대한 시사점 도출로, 관련 문헌 분석 및 교원양성기관의 진로교육 관련 강좌 강의계획서 내용 분석을 통하여 시사점을 도출하였다. 분석 결과, 첫째, 초등학교에서의 진로교육개념, 초등학교의 진로교육에서 교사의 역할 등의 내용을 다루고 실제로 모의수업을 통해 경험해 보는 강의가 필요하다. 또한, 초등 진로교육 단계의 진로교육 목표 중 중요한 부분의 하나가 긍정적인 직업관 형성이라는 점을 고려하여 그에 대한 내용도 중요하게 다루어질 필요가 있다. 둘째, 중등교원 양성기관에서는 교직이수 및 대학원 등의 과정보다 체계적으로 운영된다고 볼 수 있는 사범대학 내에서도 교원의 진로교육역량을 개발하기 위한 교육 프로그램에 대한 인식과 실천이 미흡하다고 볼 수 있다. 예비교사의 진로교육역량을 강화하기 위해서는 예비교사가 필수로 이수하는 교육과정 내에서 진로교육과 관련한 구체적인 교육과정운영 가이드라인 제시가 필요하며, 현재 중등교원 양성기관에서 이루어지는 교육과정에 대한 개선 및 보완을 위해 표준화된 교육 내용 및 방법을 제시할 필요가 있다.

In treatment of failure in ankle joint replacement therapy, talar avascular necrosis with massive bone defect, talus fracture with severe comminution and bone defect and ankle dislocation, treatment of large bone defects is considerably important for ankle joint stability and union, therefore, the choice of treatment for large bone defects is use of femoral head or iliac crest bone graft and rigid internal fixation. Because first generation total ankle arthroplasty performed for the first time using a cemented fixation technique requires a large amount of bone resection during re-surgery and there is some possibility of a larger bone defect after removal of implants, in cases where prosthesis for the defect is needed, performance of palliative femoral head or iliac crest bone graft and rigid internal fixation can be difficult. We report on a case of a 48-year-old woman who had experienced ankle pain for 25 years since undergoing total ankle arthroplasty. Because the patient had little ankle motion and rigid soft tissue despite a large bone defect caused by aseptic loosening, a good outcome was obtained only for the femoral cancellous bone graft using allo femoral head without internal fixation.

Septic arthritis caused by Klebsiella pneumonia in adults is rare and is rarely observed after total knee arthroplasty. Acute or early onset of septic arthritis caused by K. pneumoniae has been reported after total knee arthroplasty. However, to date the only one overseas case of late K. pneumoniae infection after total knee arthroplasty has been reported, with no such case in Korea. In addition, monomicrobial infections by K. pneumoniae are not frequently found but are found primarily in the form of polymicrobial infections. The purpose of this paper is to report on a case in which an 85-year-old female patient, who had undergone a total joint arthroplasty 11 years ago, developed the late onset of septic arthritis caused by monomicrobial K. pneumonia infection with a periprosthetic fracture through literature reviews.

Streptococcus sanguis (S. sanguis) is a gram positive streptococcus bacteria which is found in the normal bacterial fl ora of the oral cavity and the upper respiratory tract. It has low virulence, but it can cause bacterial endocarditis through the blood circulation when dental calculus are removed from the teeth or during surgical treatment. Septic arthritis caused by S. sanguis has been reported as infecting the sternoclavicular joint and the knee joint, but it is a quite rare infectious disease that has not been reported in Korea. Therefore, the authors report a case of the septic arthritis in the knee joint caused by S. sanguis in a patient with osteoarthritis of the knee, who has the history of periodontitis.