• Journal of Veterinary Clinics
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• v.33 no.5
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• pp.295-299
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• 2016

A 2-year-old, 1.94 kg spayed female Toy Poodle was referred for revision surgery for patellar reluxation following surgery for bilateral medial patellar luxation (MPL). Intermittent non-weight-bearing lameness of the right hindlimb and weight-bearing lameness of the left hindlimb were evident on general inspection. A physical examination revealed that there was a bilateral grade 4 MPL. On radiographs, the medial and lateral trochlear ridge was bilaterally worn out. Patellar groove replacement (PGR) was performed in two stages to replace the bilateral femoral trochlea that had a severely worn out groove. Corrective femoral osteotomy with increasing anteversion angle, tibial tuberosity transposition, medial releasing, lateral imbrications and PGR were performed on the right hindlimb. Six months after surgery on the right hindlimb, a PGR prosthesis was positioned medially on the frontal plane and tibial tuberosity transposition and lateral imbrications were performed on the left hindlimb. Two weeks after surgery, reluxation of the patella occurred on the left hindlimb. The tibial tuberosity transposition was performed to realign the patella more laterally than the previous surgery, and a patellar sling was applied. Two years after the last surgery, the patient showed no pain on the stifle joint and satisfactory weight-bearing ambulation. Reluxation did not recur. PGR maybe a successful treatment for dogs with iatrogenically damaged and/or worn out patellar grooves.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.5
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• pp.859-864
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• 2013

Creation of a stress relief groove is a fairly simple yet high-performance method. During the application of this method, it is important to consider the location and size of the groove in order to achieve better performance. Consequently, this research proposes an approach for optimizing the application of the stress relief groove method to a press-fitted assembly. In a boss design, the position and diameter of the groove are configured as design variables and the design of experiments is applied. Based on this information, a 3D model is built and analyzed using the finite element analysis software ABAQUS. Meta-models are created using back-propagation neural networks. Then, deterministic optimization results obtained from a genetic algorithm are compared with the results of the finite element analysis. The temperature sensitivity of the optimized model is analyzed, and finally, reliability-based design optimization is conducted for enhancing the design quality.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.335-340
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• 2006

Lower palpebral bags and tear trough grooves are the common signs of aging. Weakness of the orbital septum, atrophy of the orbicularis oculi muscle, slackness and laxity of the lower lid skin are the main causes of these aging changes. Tear trough groove with skeletonization of the lower orbital rim can not be corrected easily by the conventional lower blepharoplasty, but the augmentation of the volume, can be an effective method. Lower lids provide a well vascularized recipient site, which is vital for proper grafting of fat to occur. We treated tear trough groove with free fat graft of surgically removed orbital fat. Surgical excision of the fat pad and septal reinforcement with free fat graft below the levator labii superioris alaeque nasi muscle were performed to correct tear trough groove. This technique was performed in 29 consecutive individuals from October, 2001 to January, 2005. Palpebral bags and tear trough groove were corrected concomitantly and obtained a youthful attractive midface with no secondary hollowness of lower lid and irregularity. The overall results obtained were satisfactory without any complications. Recurrence of tear trough deformity due to grafted fat absorption was not noted during the 7 months of the follow-up period. The authors conclude that the procedure is safe and effective in selected patients.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.58-72
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• 2004

Statement of problem : Clinically, maxillary first premolar has a high risk of fracture. This is thought to be caused by the susceptible figure which the maxillary first premolar has In other words, sharp cusp angles of the premolar is thought to influence this situation. Purpose : This study was to know stress distribution of all-ceramic crown according to the cusp angle. Material and Method : It was manufactured a three dimensional finite element model simplified maxillary first premolar, and then analyzed stress distribution when cusp angle was each $80^{\circ}$, $90^{\circ}$, $100^{\circ}$, $110^{\circ}$ and $120^{\circ}$. Results and conclusion : 1. The von Misses stress showed that stress decreases as cusp angle increases in the central groove of the occlusal surface. 2. It showed that maximum principal stress was centered at the region of the central groove of the occlusal surface and a region which the force was inflicted. And also it appeared high on the lingual and buccal side of finish line. 3. The X axis of normal stress was focused in the central groove of the occlusal surface. The Y axis normal stress appeared high in the central groove of the occlusal surface, buccal and lingual side. 4. The Stress near the finish line showed a low value compared with stress in the region of the central groove of the occlusal surface. 5. It shows that the most dangerous angle for tooth fracture was on $80^{\circ}$ of the cusp angle and low on $120^{\circ}$ of its.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.127-128
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• 2010

• Journal of Korean Neurosurgical Society
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• v.39 no.2
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• pp.156-158
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• 2006

We present a case of olfactory schwannoma in a 16-year-old boy with headache and diplopia. Brain computed tomography[CT] scan and magnetic resonance[MR] imaging showed a huge mass in the subfrontal area resembling an olfactory groove meningioma. We performed a bifrontal craniotomy and found out the mass was attached to cribriform plate but was not related to the olfactory tract or bulb. The histopathological diagnosis of schwannoma was confirmed by immunohistochemical staining for S-100, vimentin and others. We describe the clinical manifestations, radiological characteristics, histological aspects, and differential diagnosis of this tumor with literature review.

• International Journal of Fluid Machinery and Systems
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• v.7 no.2
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• pp.80-85
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• 2014

In this study, we visualized the internal flow of a regenerative turbomachinery using the direct injection tracer method. For visualization, the working fluid was water and the tracer was oil colors (marbling colors). Droplets were injected at the inlet of the machinery and the streak were recorded using a high-speed camera with high-power light sources. While circulating inside the groove, the droplets were translated by the rotational motion of the impeller. When the droplets flow out of the impeller groove, relative to the impeller, they moved more slowly. And the droplets repeatedly reentered into the groove and circulated again. Then the droplets either flowed to the outlet or to the stripper. As a result, this experiment has confirmed the internal circulating flow of a regenerative turbomachinery.

• Tribology and Lubricants
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• v.22 no.4
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• pp.211-217
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• 2006

Ring and groove wear may not be a problem in most current automotive engines. However, a small change in ring face and groove geometry can significantly affect the lubrication characteristics and ring axial motion. This in turn can cause to change inter-ring pressure, blow-by and oil consumption in an engine. Therefore, by predicting the wear of piston ring face, ring groove and cylinder bore altogether, the changed ring end gap and the changed volume of gas reservoir can be calculated. Then the excessive oil consumption can be predicted. Being based on the calculation of gas flow amount by the theory of piston ring dynamics and gas flow, and the calculation of oil film thickness and friction force by the analysis of piston ring lubrication, the calculation theory of oil amount through top ring gap into combustion chamber will be set. This is estimated as engine oil consumption. Furthermore, the wear theories of ring, groove and cylinder bore are included. Then the each amount of wear is to be obtained. The changed oil consumption caused by the new end gap and the new volume of oil reservoir around second land, can be calculated at some engine running interval. Meanwhile, the wear amount and oil consumption occurred during engine durability cycle are compared with the calculated values. Next, the calculated amount of oil consumption and wear are compared with the guideline of each part's wear and oil consumption. So, the timing of part repair and engine life cycle can be predicted in advance without performing engine durability test. The wear data of rings and grooves are obtained from three engines before and after engine durability test. The calculated wear data of each part are turn out to be at the lower bound of aver-aged test values or a little below.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.169-176
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• 2018

Removal of angular deformation induced during the welding of butt joints in thick steel plates needs expert skill and is costly. To reduce deformation, proper joint designs are studied with a prediction of deformation prior to welding. However, as the thickness of a plate increases, a predictive analysis of the welding process is more difficult, especially if there is an increase in the number of welding passes in the joint. In this study, a numerical model with the finite element method (FEM) was developed to analyze the angular deformation in the multi-pass welding of butt joints of plates made of AH32 steel that had a thickness of up to 100 mm. A series of numerical simulations were then performed based on the developed model to predict the deformations for thick plates. With the results obtained by the analyses, this study suggested optimal X-shape grooves for the butt joints of thick plates to minimize the angular deformation. As the thickness of the plate increased to 100 mm, the ratio of the depth of the front-side groove to that of the back-side groove should be gradually increased to nearly 1:3.

• Tribology and Lubricants
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• v.28 no.6
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• pp.278-282
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• 2012

Various bearings such as deep-groove ball bearings, angular-contact ball bearings, and roller bearings are used to support the load and to lubricate between the shaft and the housing. The bearings of potential rolling systems in a turbo pump are the deep-groove ball bearings as comparing with the bearings with rolling elements such as cylindrical rollers, tapered cylindrical rollers, and needle rollers. The deep-groove ball bearings consist of rolling elements, an inner raceway, an outer raceway and a retainer that maintain separation and help to lubricate the rolling element that is rotating in the raceways. In the case of water-lubricated ball bearings, however, fluid friction between the ball and raceways is affected by the entry direction of flow, rotation speed, and flow rate. In addition, this friction is the key factor affecting the bearing life cycles and reliability. In this paper, the characteristics of flow conditions corresponding to a deep-groove ball bearing are investigated numerically, with particular focus on the friction distribution on the rolling element, in order to extend the analysis to the area that experiences solid friction. A simple analysis model of fluid flow inside the water-lubricated ball bearing is analyzed with CFD, and the flow characteristics at high rotation speeds are presented.