• Earthquakes and Structures
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• v.12 no.2
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• pp.251-262
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• 2017

The present research intends to study the effects of the seismic soil-foundation-structure interaction (SFSI) on the dynamic response of various buildings. Two methods including direct and Cone model were studied through 3D finite element method using ABAQUS software. Cone model as an approximate method to consider the SFSI phenomenon was developed and evaluated for both high and low rise buildings. Effect of soil nonlinearity, foundation rigidity and embedment as well as friction coefficient between soil-foundation interfaces during seismic excitation are investigated. Validity and performance of both approaches are evaluated as reference graphs for Cone model and infinite boundary condition, soil nonlinearity and amplification factor for direct method. A series of calculations by DeepSoil for inverse earthquake record modification was conducted. A comparison of the two methods was carried out by root-mean-square-deviation (RMSD) tool for maximum lateral displacement and story shear forces which verifies that Cone model results have good agreement with direct method. It was concluded that Cone method is a convenient, fast and rather accurate method as an approximate way to count for soil media.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.65-68
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• 2010

Purpose: Dermoid cysts are benign neoplasms that are derived from both ectoderm and mesoderm. Approximately 7 percent of all dermoid cysts occur in the head and neck, as most common sites are the lateral ends of the eyebrows, the midline in the nasal root and neck. Rarely they can be found in the frontal sinus, temporal bone, maxilla and the floor of the mouth. Dermoid cysts in the temporal fossa are extremely rare. We experienced a characteristic dermoid cyst that occupied the temporal fossa. Methods: A 16-year-old man had a progressive enlarging mass on the left eyebrow. Computerized tomographic scan showed a bulging mass in the temporal fossa, and it had the density similar to that of fat. The size of the mass was $3{\times}3{\times}2cm$, and it was composed of high density of fat with clear margin. There was no bony invasion, but the mass was fixed on bone. Results: We performed the surgery through coronal incision under general anesthesia. Because the mass was closely connected with temporal fat pads, we removed this mass with some portion of temporal fat pads, avoiding damage to the facial nerve. The postoperative course was ordinary without complication. Conclusion: The reports about dermoid cyst on the temporal fossa is uncommon. However, if there is a mass in the temporal fossa which has the density similar to that of fat in CT scan, we should consider the possibility of dermoid cyst. We suggest that excision through coronal incision with bewaring temporal fat pad can induce good result.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.7
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• pp.605-611
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• 2011

Shimmy is a self-excited vibration in lateral and torsional directions of a landing gear during either the take-off or landing. It is caused by a couple of conditions such as a low torsional stiffness of the strut, a free-play in the landing gear, a wheel imbalance, or worn parts, and it may make the aircraft unstable. This study was performed for an analysis of the shimmy stability on a small aircraft. A nose landing gear was modeled as a linear system and characterized by state-equations which were used to analyze the stability both in the frequency and time-domain for predicting whether the shimmy occurs and investigating a good design range of the important parameters. The root-locus method and the 4th Runge-Kutta method were used for each analysis. Because the present system has a simple mechanism using a friction to reinforce the stability, the friction, a non-linear factor, was linearized by a describing function and considered in the analysis and observed the result of the instability reduction.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.704-709
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• 2006

Ectopic eruption should be understood as a change in the course of the normal eruption path of a dental bud at any moment in its origin. Transposition is a unique and extreme form of ectopic eruption. The treatment for ectopic eruption and transposition is various from simple observation to surgical exposure and orthodontic traction, according to direction of erupting tooth degree of developing root apex and eruption space etc. Autotransplantation is transplantation of tooth from one area of the mouth to another in the same individual or is moving a eruption tooth into extraction socket or surgically prepared socket, and autotransplantation is considered as a treatment of choice for the ectopic eruption when orthodontic traction is unable or when tooth movement is limited. These cases which were treated with autotransplantation of maxillary lateral incisor and maxillary canine were reported, and good esthetic and functional result were induced.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.189-195
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• 2002

Soybean sprout trails were evaluated for soybeans for sprout (Glycine max) and wild soybeans (Glycine soja). Soybeans for sprout are characterized with small seed size of 10-14 grams per 100 seeds and are traditionally used only for producing sprouts. No difference was observed in hypocotyl length and sprout yield between two types of soybean. (However total length, hypocotyl hypocotyl, body weight, and the rate of good quality were greater in soybeans for sprout.) Number of lateral roots and root length were greater in wild soybeans. Contents of crude oil, oleic acid, and sucrose were higher in soybean for sprout, while that of protein and linoleic acid were higher in wild soybeans. There was no difference in sprout isoflavone content. Out of 17 amino acids analyzed, 10 amino acids such as aspartic acid, lysine, and arginine. etc. showed significantly Higher content in wild soybeans. Hypocotyl color of sprouts estimated by color meter based on the degree of L(brightness), a(red), and b(yellow) values were better in wild soybeans than soybean for sprout.

• Archives of Plastic Surgery
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• v.39 no.3
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• pp.190-197
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• 2012

Background : This article presents long-term outcomes after correcting secondary bilateral cleft lip nasal deformities using a refined reverse-U incision and V-Y plasty or in combination with a composite graft in order to elongate the short columella. Methods : A total of forty-six patients underwent surgery between September 1996 and December 2008. The age of the patients ranged from 3 to 19 years of age. A bilateral reverse-U incision and V-Y plasty were used in 24 patients. A composite graft from the helical root was combined with a bilateral reverse-U incision in the 22 patients who possessed a severely shortened columella. The follow-up period ranged between 2 and 10 years. Results : A total of 32 patients out of 46 were evaluated postoperatively. The average columella length was significantly improved from an average of 3.7 mm preoperatively to 8.5 mm postoperatively. The average ratio of the columella height to the alar base width was 0.18 preoperatively and 0.29 postoperatively. The postoperative basal and lateral views revealed a better shape of the nostrils and columella. The elongated columella, combined with a composite graft, presented good maintenance of the corrected position with no growth disturbance. A composite graft showed color mismatching in several patients. Twenty-six patients demonstrated no alar-columella web deformity and satisfactory symmetry of the nostrils. Four patients experienced a drooping and overhanging of the corrected alar-columella web. Conclusions : A bilateral reverse-U incision with V-Y plasty or in combination with a composite graft was effective in correcting secondary bilateral cleft lip nasal deformity.

• Journal of Periodontal and Implant Science
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• v.28 no.1
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• pp.187-191
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• 1998

Aplastic anemia is a disease characterized by general lack of bone marrow activity; It may affect not only the red blood cells but also the white blood cells and platelets, resulting in pancytopenia. Spontaneous gingival hemorrhage is present in some cases and it is related to the blood platelet deficiency. This case report presents the periodontal treatment of a patient with aplastic anemia. A 43-year-old female was referred for continuous gingival bleeding after periodontal treatment. Periodontal findings revealed generalized gingival imflammation, oozing of blood from gingival crevice, and it was diagnosed as adult periodontitis. Root planing and extraction of the upper left third molar with poor prognosis were put into operation after elevation of the platelet count with platelet transfusion. The extraction socket was sutured with 3-0 silk. Bleeding continued even after digital compression at the upper right second premolar, second molar, and left canine areas, which presented severe inflammation. Although platelets were transfused repeatedly, platelet count did not stay elevated since survival rate of the transfused platelets were low due to alloimmunization. Thrombin gauze packing was not effective. Bleeding ceased 3 days after treatment with transfusion of donor platelets. 20 days after the treatment, the gingiva was generally healthy except upper right second premolar and lateral incisor areas. The result of periodontal treatment was good, but bleeding control after treatment was troublesome. In the periodontal treatment of patient with aplastic anemia, elevation of the platelet count with platelet transfusion seems to be the best method for hemorrhage control.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.373-384
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• 2003

The purpose of this study was to evaluate the eruption pattern of a cyst-associated mandibular premolar after marsupialization of a dentigerous cyst in children. The result from the twenty two pairs of normalized panoramic radiographs of twenty two patients who underwent neither extraction nor orthodontic traction of the cyst-associated mandibular after marsupialization were as follows. 1. The eruption speed of a cyst-associated premolar was 3.5 times faster than that of the normal contra-lateral premolar(p<0.05). The angulation change of test group was an average of $2.7^{\circ}$ per month. 2. In the change of the level of root formation, the group which had a little root maturity tended to be faster in the eruption speed(p>0.05) and the R1/4 group had a great change in the angulation change(p>0.05). 3. In the change to be with the cusp position index, the eruption speeds were increased to the 30% deviation groups. But, the eruption speed was decreased above that(p>0.05). 4. Group with cyst diminishment rate of more than $80mm^2$ per month showed the fastest eruption speed of all(p<0.05). 5. The mesial angulated teeth in the test group were decreased more rapidly than the distal angulated teeth in the eruption speed(p>0.05). But, increased in the angulation change(p<0.05). 6. There was a tendency of faster tooth eruption with less deviation of tooth axis. Group with tooth axis deviation of less than $15^{\circ}$ showed the fastest angulation change of all(p<0.05). 7. The eruption speed and the angulation change rapidly decreased during the first 6 months following marsupialization. Based on the results of this study, a cyst-associated mandibular premolar erupted more rapidly after marsupializaton. We thought so that it's prognosis was good if the tooth had a little root maturity, a little devitation and cyst lesion healed faster. We recommend that if there is enough space for eruption, orthodontic traction and surgical treatment of the cyst-associated tooth should be postponed 6 months after marsupialization.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.35-43
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• 2000

Objective : Percutaneous lumbar approaches such as arthroscopic discectomy, laser discectomy, and nucleotome remain controversial and have technical limitations to free fragment disc, bony pathology and access to L5-S1, The purpose of this study was to determine efficacy of this new endoscopic system and to report techniques and tactics. Methods : From July 1997 to May 1998, we treated 40 consecutive patients(43 levels) with the MED system. Mean age was 32 years(range ; 18 to 62). There were 30 males and 10 females. All patients had sciatica with SLRT limitation. There were 23 patients with disc herniation at L4-5 and 14 patients at L5-S1. Three patients had 2 level disc herniations. There was one far lateral disc herniation at L4-5. Results : Using modified MacNab criteria, there were 37 excellent results and 3 good result. Most patients were discharged within 3-4 days except 2 patients with dural tearing. There were no other complications. Mean operation time was 1.5 hours(range : 40 minutes to 2.5 hours). Conclusion : The MED system is a reliable approach to lumbar disc herniations. This system combines the advantages of conventional open surgery and a minimally invasive technique. As tactics for the doctors who wish to attempt, "palpate" the lamina by first dilator, identification of interlaminar space by removal of overlying soft tissue and confirmation of the shoulder portion of nerve root before discectomy are important to this procedure. We conclude that lumbar disc herniations can be successfully treated with MED approach.