• Journal of Welding and Joining
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• 제35권3호
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• pp.44-51
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• 2017

In the present study, AA 5083-O plates are joined by friction stir welding technique. A universal milling machine was used to perform the welding process of the work-pieces which were fixed on the proper position by a vice. The joints were friction stir welded by two tools with different pin profiles; cylindrical threaded pin and tapered smooth one at different rotational speed values; 400 rpm and 630 rpm, and different welding speed values; 100 mm/min and 160 mm/min. During FSW of each joint, the temperature was measured by infra-red thermal image camera. The welded joints were inspected by visually as well as by the macro- and microstructure evolutions. Furthermore, the joints were tested for measuring the hardness and the tensile strength to study the effect of changing the FSW parameters on the mechanical properties. The results show that increasing the rotational speed results in increasing the peak temperature, while increasing the welding speed results in decreasing the peak temperature for the same tool pin profile. Defect free welds were obtained at lower rotational speed by the threaded tool profile. Moreover, the threaded tool pin profile gives superior mechanical properties at lower rotational speed.

• 대한족부족관절학회지
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• 제19권1호
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• pp.11-17
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• 2015

Purpose: To report the radiographic and clinical results of 6.5 mm cancellous full threaded buttress screw or Steinmann pin fixation to maintain a reduction of calcaneal posterior facet depression fracture. Materials and Methods: From June 2009 to June 2012, 50 consecutive cases with calcaneal joint depression fracture that underwent open reduction and screw or pin fixation were enrolled in this study. A 6.5 mm cancellous full threaded screw was inserted from the posteroinferior aspect of the calcaneal tuberosity to the posterior facet (group A) or Steinman pin was inserted from the posterosuperior aspect of the calcaneal tuberosity to the calcaneocuboidal joint (group B). Both preoperative and postoperative Bohler and Gissane angles were measured radiographically, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale on the final follow-up were assessed. Results: The mean age of patients was 44.1 years, and the mean follow-up period was 27.2 months. According to the Sanders classification, 28 cases were type II and 22 cases were type III. In Sanders type II, Bohler and Gissane angles improved significantly from $10.1^{\circ}$ and $126.2^{\circ}$ preoperatively to $27.2^{\circ}$ and $117.1^{\circ}$, respectively, in the immediate postoperative radiograph, and at the final follow-up, $26.6^{\circ}$ and $118.6^{\circ}$, respectively. In Sanders type III, Bohler and Gissane angles improved significantly from $5.0^{\circ}$ and $129.8^{\circ}$ to $29.9^{\circ}$ and $119.3^{\circ}$, respectively, in the immediate postoperative radiograph, and $26.9^{\circ}$ and $120.2^{\circ}$ at the final follow-up. All cases achieved bony union, and the average period until complete union was 13.3 weeks. AOFAS ankle-hindfoot scale was 82.6 in Sanders type II and 77.3 in Sanders type III at the final follow-up. Conclusion: A 6.5 mm cancellous full threaded buttress screw or Steinman pin fixation is a noninvasive treatment method with a merit of being able to maintain the bearing capacity of the posterior facet comparable to plate fixation.

• 한국임상수의학회지
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• 제24권4호
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• pp.631-635
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• 2007

Luxation of the hip is the most common luxation seen in small animals. Luxations are classified by the direction in which the femoral head lies in relation to the acetabulum and craniodorsal luxations are the most common type. Recommendations for treatment are based on the presence of preexisting disease, the type and duration of luxation and severity of concurrent injuries. In this study modified external skeletal fixation was used for craniodorsal coxofemoral luxation in 5 dogs. Luxated head Joint was reduced and fixator pins were applied into the greater trochanter, the middle point of iliac body and the lateral surface of sacroiliac joint in a closed fashion. Reduction was successful in 4 of the 5 operated limbs. Complications noted in this study included pin tract drainage, pin loosening and secondary fracture at the pin insertion site.

• Journal of the Korean Wood Science and Technology
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• 제23권3호
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• pp.8-15
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• 1995

This analytical study was carried out to make quality and productivity up in designing the frame-type furniture with semi-rigid joint by understanding the mechanical and structural behavior of the joint and by evaluating the validity of application of the time-saving Finite Element Method to its structural analysis. Slope deflection equation for rigid joint was modified to describe the moment-rotation behavior of semi-rigid joint and the joint stiffness factor(Z) could be calculated to lessen the experimental expense. It was proved that Finite Element Analysis with imaginary elements having equivalent MOE to the semi-rigid joint could be the alternative method for the structural analysis of the frame-type furniture, comparing the internal rotation of the 2-dimensional beam-to-column model with two-pin(wooden dowel) from the finite element method with other available theoretical and experimental rotation value.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.173-176
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• 2002

Fundamental failure mode in a laminated composite pinned joint is proposed to assess damage resulting from stress concentration in the plate. The joint area is a region with stress concentrations thus a complicated stress state exists. The modeling of damage in a laminated composite pinned joint presents many difficulties because of the complexity of the failure process. In this study, the effect on the bearing strength of the pin jointed Carbon Fiber Reinforced Plastics (CFRP) composites for magnet support structure of KSTAR tokamak with various parameters such as edge distance to diameter, width to diameter, and the temperature of $23^{\circ}C$, $-76^{\circ}C$, and $-196^{\circ}C$ was examined by comparing the experimental results with finite element analysis.

• 항공우주기술
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• 제12권1호
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• pp.105-110
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• 2013

액체로켓엔진 고압 배관의 김발 신축이음은 고압에서 반복적인 회전 변위를 받게 된다. 본 연구에서는 고압에서 내부형 김발 신축이음의 모멘트 해석 및 시험을 수행하였다. 해석적으로 스프링 강성, 마찰과 측력에 의한 모멘트 값을 각각 구하고 시험으로 얻어진 전체 모멘트 값과 비교하였다. 또한 외부형 힌지 신축이음에 대하여 회전 핀에 이황화몰리브덴 코팅을 적용하여 저압에서 갈링 현상이 없어지고 마찰 계수가 감소하는 것을 확인하였다.

• 한국강구조학회 논문집
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• 제10권4호통권37호
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• pp.769-777
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• 1998

본 연구의 목적은 삼각형네트워크를 갖는 핀접합 단층래티스돔이 형상초기부정을 가질 경우 하중상태에 따라 좌굴특성에 미치는 영향을 검토하는 것이다. 또한 형상초기부정을 고려하는 단층래티스돔의 일반화 좌굴내력식의 개발을 위한 기초자료를 수집하는데 있다. 해석은 유한요소법에 의한 이산화해석법을 이용했다.

• Journal of Korean Neurosurgical Society
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• 제37권4호
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• pp.293-295
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• 2005

Posterior interosseous nerve(PIN) syndrome is an entrapment of the deep branch of the radial nerve just distal to the elbow joint. It is caused by acute trauma or masses compressing the nerve. We report an unusual case of PIN syndrome with wrist drop caused by compression of the nerve by anomalous vascular leash. The patient has recovered with the surgical decompression of the offending vessels and arcade of Frohse.

• 한국해양공학회지
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• 제18권5호
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• pp.36-42
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• 2004

Orthotropic laminates, such as [$0^{\circ}6$/$90^{\circ}6$]s and [$90^{\circ}6$/$0^{\circ}6$]s, were performed, using a commercial nonlinear finite element method. Interlaminar stress distributions, around the hole curve free-edge, were calculated. The delamination bearing strengths of pin joints were predicted, using the modified delamination failure criterion. These stress distributions were presented along the radial lines and around the free-edge of the hole. Further, three-dimensional non-linear contact analysis of orthotropic laminates was conducted to investigate the effect of friction. In this paper, laminates with a circular hole were taken to study interlaminar stresses the curved edge. This study may assist in the design of a thick composite laminate with mechanically pin joints.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1289-1294
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• 2008

Electrostatic discharge(ESD) phenomenon is a serious reliability concern. It causes approximately most of all field failures of IC. To quality the ESD immunity of IC product, there are some test methods and standards developed. ESD events have been classified into 3 models, which are HBM, MM and CDM. All the test methods are designed to evaluate the ESD immunity of IC products. This study provides an overview among ESD test methods on ICs and an efficient ESD stress method. We have estimated on all pin combination about the positive and negative ESD stress. We make out the weakest stress mode. This mode called a worst-case mode. We proposed that positive supply voltage pin and I/O pin combination is efficient because it is a worst-case mode.