• Journal of the Korea Furniture Society
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• v.21 no.1
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• pp.26-39
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• 2010

This is a leading study to replace the structural analysis methodology on the specific traditional joint by a numerical analysis. Tests were carried out to test the compressive methodologies with the numerical results. The Japanese larch was used as a sample. The Orthotropic property of wood was specifically considered for the finite element numerical analysis. Linear numerical analysis and non-linear numerical analysis for the BEAM element and the two SOLID elements of ANSYS were used to analyze the compressive performance. In addition, more finely divided elements were used to raise the accuracy of the numerical result. Finally, the statistically significant differences were tested between that of the analytical and numerical results. It could be concluded that the SOLID 64 element shows the most optimum result when the non-linear analysis with the more finely divided element was used. However, finely dividing of the element is a considerable time consuming process, and it is quite difficult to raise the accuracy of the non-linear numerical analysis. Therefore, if considering the vertical displacement to be of the only interest, the BEAM element is more efficient than the SOLID element because the BEAM element is reflected as a simple line, which is less time consuming and difficult in dividing the elements. But, the BEAM element cannot accurately model the knot as a strength defect factor which is an important property in the orthotropic property of wood. Therefore, the SOLID element should be used to model the strength defect factor, knot, as it can be efficiently applied on the structural size flexure member which could be more strongly effected by the knot. In addition, it is useful at times when the failure types of members are to be more closely investigated, as the SOLID element is able to examine the local stress distribution of the member. The conclusion drawn by this study is of the good concordance between analytical results and numerical results of compressive wood members, but how orthotropic properties should only be considered. The numerical analysis on the specific Korean traditional joints will be based on the current study results.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.2
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• pp.150-156
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• 2011

In this paper, infrared thermography measurement technique has been used to develop standard measurement technique for nondestructive testing of composite materials which is widely used in aerospace industries. To increase the defect detection rate, the related experiment used the lock-in IR-thermographiy method. Therefore it is of considerable interest in the field of non-destructive testing for fast discontinuity detection by using ultrasonic lock-in infrared thermography. The result also shows that as the investigation period of light source is lengthened according to the thickness of specimen, the possibility of detecting defects gets higher as well. However, the reason why the result values were not favorable when less than 50 mHz of light source was provided is because it was difficult to detect defects as the defect parts became a state of thermal equilibrium in general when thermal diffusivity affects the entire materials.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.5
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• pp.380-390
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• 2004

Bone healing plays an important role in orthognathic and craniofacial surgery. Bone tissue repair and regeneration are regulated by an array of growth and morphogenetic factors. Bone formation and remodeling require continuous generation of osteoprogenitor cells from bone marrow stromal cells, which generate and respond to a variety of growth factors with putative roles in hematopoiesis and mesenchymal differentiation. In this study, the efficacy of a single application of hepatocyte growth factor to promote bone regeneration in 5-mm experimental calvarial defects of adult male rats was assessed histologically and immunohistochemically. The result of the experimental site were compared with those of the contralateral contral side. None of the control and experimental bone defects demonstrated complete bone closure. Bone regeneration was found close th the margine and central part of the defects. At 1, 2 weeks, there were found much significant cellural mitotic activity and many inflammatory cells and osteoblasts on the experimental site than control site. At 4, 6 weeks, new bone apposition was founded in both site but, more apposition was seen at experimental site. At 8, 12 weeks, also, some differences was found that more apposition of new bone and collagen fiber was seen on experimental site. Our results have some possibility that HGF do a early positive role to repair the bone defect. More study will be needed.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.110-120
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• 2009

Recently raising the recognition and it joins in about software quality evaluation and authentication and the recognition is augmented in about importance of the high quality security which leads a quality investment from the software development enterprise. The quality investor do to become accomplished but substantially from which degree level, quality investment it leads and the verification of software quality improvement does not become accomplished substantially and with without being it does and wants the enterprises where are clear the quality improvement which leads a quality investment does not set the direction where the problem occurs. From the research which it sees international ISO/IEC 9126 where it is standard and in about software test ISO/IEC 12119 where it is a guide it constructed the metric in base and software tentative instance it led and is accumulated and the defect data which it analyzed. result escape it investigated/to analyze quality level and it analyzed is weak from development process part and a defect level and the quality rating instance of Middleware] software and escape a disposal plan it investigated. The research which it sees it leads and it induces it is quantitative/that there is a possibility of being sufficient it sees the quality increase of Middleware software and the demand which is qualitative.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.91-99
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• 2001

In this study the possibility of classifying wood surface defects by image processing technique was investigated. An algorithm for the classification of wood surface defects, such as knot, check, and bark, on three Korean domestic species, Pinus densiflora, Quercus acutissima, and Carpinus laxiflora was also developed. Filtering was executed to separate dummies from the labels including real defect. Error rates in classifying knots on Pinus densiflora and Quercus acutissima were lower than 1% and error rates. In classifying check and bark in Quercus acutissima and Carpinus laxiflora could be lowered to below 13%.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.653-658
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• 2008

Purpose: Skin and soft tissue defect is one of the major challenges faced by plastic surgeons. Adipose derived stromal cells, which can be harvested in large quantities with low morbidity, display multilineage mesodermal potential. Therefore, adipose derived stromal cells have been met with a great deal of excitement by the field of tissue engineering. Recently, Adipose derived stromal cells have been isolated and cultured to use soft tissue restoration. In order to apply cultured cells for clinical purpose, however, FDA approved facilities and techniques are required, which may be difficult for a clinician who cultures cells in a laboratory dedicated to research to utilize this treatment for patients. In addition, long culture period is needed. Fortunately, adipose derived stromal cells are easy to obtain in large quantities without cell culture. The purpose of this study is to present a possibility of using uncultured adipose derived stromal cells for wound coverage. Methods: Seven patients who needed skin and soft tissue restoration were included. Five patients had diabetic foot ulcers, 1 patient got thumb amputation, and 1 patient had tissue defect caused by resection of squamous cell carcinoma. The patients' abdominal adipose tissues were obtained by liposuction. The samples were digested with type I collagenase and centrifuged to obtain adipose derived stromal cells. The isolated adipose derived stromal cells were applied over the wounds immediately after the wound debridement. Fibrin was used as adipose derived stromal cells carrier. Occlusive dressing was applied with films and foams and the wounds were kept moist until complete healing. Results: One hundred to one hundred sixty thousand adipose derived stromal cells were isolated per ml aspirated adipose tissue. All patients' wounds were successfully covered with the grafted adipose derived stromal cells in a 17 to 27 day period. No adverse events related to this treatment occurred. Conclusion: The use of uncultured adipose derived stromal cells was found to be safe and effective treatment for wound coverage without donor site morbidity.

• Tuberculosis and Respiratory Diseases
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• v.76 no.3
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• pp.136-140
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• 2014

Pulmonary artery sarcoma (PAS) is a rare, poorly differentiated malignancy arising from the intimal layer of the pulmonary artery. Contrast-enhanced chest computed tomography (CT) is a good diagnostic modality that shows a low-attenuation filling defect of the pulmonary artery in PAS patients. An 18-year-old man was referred to our hospital for the evaluation and management of cavitary pulmonary lesions that did not respond to treatment. A contrast-enhanced CT of the chest was performed, which showed a filling defect within the right interlobar pulmonary artery. The patient underwent a curative right pneumonectomy after confirmation of PAS. Although lung parenchymal lesions of PAS are generally nonspecific, it can be presented as cavities indicate pulmonary infarcts. Clinicians must consider the possibility of PAS as well as pulmonary thromboembolism in patients with pulmonary infarcts. So, we report the case with PAS that was diagnosed during the evaluation of cavitary pulmonary lesions and reviewed the literatures.

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.803-814
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• 2000

Current acceptable methods of promoting periodontal regeneration are basis of removal of diseased soft tissue, root treatment, guided tissue regeneration, graft materials, biological mediators. Platelet Rich Plasma have been reported as a biological mediator which regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purpose of this study is to evaluate the possibility of using the Platelet Rich Plasma as a regeneration promoting agent for furcation involvement defect. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on mandibular third(P3), forth(P4) and fifth(P5) premolar. 2 month later experimental group were PRP plus bovine bone and bovine bone only. After 4, 8 weeks, the animals were sacrificed by perfusion technique. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. At 4 weeks after surgery, there were rapid osteogenesis phenomenon on the defected area of the Platelet Rich Plasma plus bovine bone group and early trabeculation pattern was made with new osteoid tissue produced by activated osteoblast. Bone formation was almost completed to the fornix of furcation by 4 weeks after surgery. In conclusion, Platelet Rich Plasma can promote rapid osteogenesis during early stage of periodontal tissue regeneration.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.197-202
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• 2007

Purpose: The gluteal artery perforator flaps earned its popularity in buttock reconstruction due to the lower morbidity of the donor site and the flexibility in the design. Speedy and safe reconstruction is important for the success of buttock reconstruction. If a proper design is selected, satisfactory results can be obtained with more simple method of surgery. Methods: Between April 2005 and April 2006, buttock reconstruction by using gluteal artery perforator flaps were performed on sacral sores(6 cases), ischial sores(2 cases) and malignant melanoma on buttock(1 case). Various designs depending on the location and the size of the defect was made. In those designs, perforator was used as an axis for the minimal dissection of the vessel. Donor site from which sufficient amount of soft tissue can be transferred was selected, and also not causing high tension against the recipient site during the donor site closure. In addition, postoperative aesthetics, and the possibility of another design of a second operation which can be necessary in the future, was considered. Results: Patient follow up was for a mean period of 10.8 months. All flaps survived except for one that had undergone partial necrosis. Wound dehiscence was observed in one patient treated by secondary closure. Most patients presented with cosmetically and functionally satisfying results Conclusion: By designing the flap using the perforator as an axis, depending on the defect size and degree, reconstruction can be performed with only a small tension to the donor and the recipient site. And the minimal perforator dissection allowed easier and faster reconstruction. Selection of a proper design is the key procedure which greatly affects operation time and result success.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.67-75
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• 2009

Purpose: As to the analytical method of data, the various programs in which it is used for the quantitative rating of the Tl-201 myocardial perfusion SPECT are reported that there is a difference. Therefore, the measured value error of the mutual program is expected to be generated even if the quantitative analysis is made against data of the same patient. Using quantitative index that able to represent myocardial perfusion defect level, we aimed to determine correlation among three myocardial perfusion analysis programs 4DM (4DMSPECT), QPS (Quantitative Perfusion SPECT), ECT (Emory Cardiac Toolbox) that be used generally in most departments of Nuclear Medicine. Materials and Methods: We analyzed the 145 patients who were examined by Tl-201 gated myocardial perfusion SPECT in department of nuclear medicine at Asan Mediacal Center from December 1th 2008 to February 14th 2008. We sorted as normal group and abnormal group. Normal group consist of 80 patients (Male/Female=38/42, age:$65.1{\pm}9.9$) who have low possibility of cardiovascular disease. And abnormal group consist of 65 patients (Male/Female=45/20, age:$63.0{\pm}8.7$) who were diagnosed cardiovascular disease with reversible perfusion defect or fixed perfusion defect through myocardial perfusion SPECT results. Using the 4DM, QPS, and ECT programs, the total defect extent (TDE) such as LAD, LCX, RCA and the summed stress score (SSS) have been analysed for their correlations and statistical comparison with the paried t-test for the quantitative indices analysed from each group. Results: The correlation of 4DM:QPS, QPS:ECT, ECT:4DM each group result from 145 patients is 0.84, 0.86, 0.82 at SSS, 0.87, 0.84, 0.87 at TDE, and both index showed good correlation. In paired t-test and Bland-Altman analysis results showed no statistically significant difference in the comparison of QPS:ECT at the mean SSS and TDE, 4DM:QPS, ECT:4DM comparative analysis results showed statistically significant difference at SSS and TDE index. The correlation of 4DM:QPS, QPS:ECT, ECT:4DM program results from abnormal group (65 patients) is 0.72, 0.72, 0.70 at SSS and 0.77, 0.70, 0.77 at TDE and TDE and SSS has a good correlation. In abnormal group, paired t-test and Bland-Altman analysis results showed no statistically significant difference at QPS:ECT SSS (p=0.89) and TDE (p=0.23) comparison, 4DM:QPS, ECT:4DM comparative analysis results showed statistically significant difference at SSS and TDE index (p<0.01). In normal group (80 patients), paired t-test and Bland-Altman analysis results showed no statistically significant difference at QPS:ECT SSS (p=0.95) and TDE (p=0.73) comparison. And 4DM:QPS, ECT:4DM comparative analysis results showed statistically significant difference at SSS and TDE index (p<0.01). Conclusions: The perfusion defect of the Tl-201 myocardial perfusion SPECT was analyzed in not only the patient in whom it has the cardiovascular disease but also the patient in whom the possibility of the cardiovascular disease is few. In the comparison of the all group research, the mean of the TDE and SSS, 4DM was lower than QPS and ECT progrms. Each program showed good correlation and the results showed statistically significant difference. However, in this way, it is determined to be compatible about the analysis value in which the large-scale side between the programs uses each program a difference in a clinical in the Bland-Altman analyzed result in spite of the good correlation and cannot use. but, this analyzed result will be able to be usefully used as the reference material for the clinical read and is expected.