• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.1
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• pp.55-60
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• 1997

Langerhans Cell Histiocytosis(Idiopathic Histiocytosis, Histiocytosis-X) is most often found in children and young adults, and cell proliferation with specific phenotype shows ultrastructural and immunohistochemical similarities with Langerhans Cells that normally exist in epithelium and mucosa. This disease occurs as single or multiple lesions in skull, ribs, vertebrae, mandible and long bones, and when it involves mandible, clinical sign and symptoms such as bone swelling and pain are noticed. When it involves alveolar bone, severe tooth mobility as well as gigival inflammation, proliferation, and ulceration are commonly found, and so it is not easy to differentiate it from general inflammatory diseases. Any local lesion at the tooth apex on the x-ray view needs to be differentiated from inflammatory disease, and multiple lesions from multiple ostoeoma and chronic multifocal osteomyelitis. This case is LCH in 51-year-old male patient ; this is a rare case, for the patient belongs to an age group with very low incidence rate of the disease. although three-timed biopsy tests and longterm observation at two university hospitals, it was misdiagnosed as multifocal osteomyelitis.

• The Journal of the Korean bone and joint tumor society
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• v.20 no.1
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• pp.14-21
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• 2014

Purpose: To analyze the clinical features and treatment outcome of Langerhans' cell histocytosis. Materials and Methods: From August 1996 to June 2013, 28 patients who histologically proven with LCH were analyzed of medical records, radiography, pathologic character retrospectively. Results: A total of 28 cases of LCH including 22 child has been reported. Onset age was 0.6 to 51 years old, occurred in the average age was 14.8 years. Follow-up period was 6 months to 134 months average was 44.6 months. The M:F ratio was 2.5:1. The initial symptoms was pain in 18 cases, 5 cases of pathologic fracture, 3 case of palpable mass, 1 case of discovered by accident in radiography, 1 case of torticollis. In radiological examination osteolysis was seen all cases, 7 cases showed a periosteal reaction, 1 case showed soft tissue extension. Clinical type of all cases were eosinophilic granuloma. 25 cases were classified as unifocal disease and 3 cases were multifocal single systemic diseases. In all cases, incisional biopsy was performed. After histologic confirmed, 14 cases was treated with curettage or surgical excision of the lesion and the other 14 cases were followed up without treatment. There is no death during follow up period. 11 cases has no radiological improvement after 3-6 months observation, intralesional steroid injection was performed. Conclusion: Patients with LCH who has rapid systemic onset is very rare, so if you meet the young children who suspected LCH, you shoulder avoid the examination which cause excessive radiation exposure to the young patient. In order to confirm the diagnosis of disease, biopsy is needed. Close observation after confirmed by histological method will bring the satisfactory results. But the patients who had pathologic fracture or wide bone destruction already may need curettage and bone grafting to lesion or internal fixation. The lesion which has no radiological improvement after 3-6 months observation or appear with pain interferes daily life may need local steroid injection as a good treatment.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.64-84
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• 2002

These studies were conducted to evaluate the Properties of lactic acid Producing bacteria(LAB), isolated from broiler and laying hens cecum and select the optimum strains to improve the performance, environment of poultry house, immunity, and intestinal microflora of broiler and laying hens. In experiment I , 23 LAB strains were isolated from broiler and laying hens cecum as a colony form. Six strains were selected by acid tolerance, bile salt tolerance, viability, enzyme release, antagonism, and antibiotics susceptibility. In Experiment II, selected LABs from Ex. 1 were conducted to investigate the effects of feeding various Lactobacillus on performance, nutrients digestibility, intestinal microflora, villi development and observation of epithelium surface, blood chemicals and fecal noxious gas of broiler chicks. One thousand eighty one day old broiler chicks were fed into Lactobacillus crispatus avibrol(LCB), Lactobacillus reuteri avibro2(LRB), Lactobacillus crispatus avihen1(LCH), and Lactobacillus vaginalis avihen2(LVH) at the level of 10$^4$ and 10$\^$7/cfu/g diet. Weight gam of chicks fed Lactobacillus tended to increase from the first week and was higher from 50 to 100g in Lactobacillus treatments than control. Feed intake and feed conversion were not statistically different of all treatments. Dry Matter digestibility of Lactobacillus treatments was prone to improve compared to that of control, but was not significantly different. Protein and Ca digestibility were also tended to improve in Lactobacillus treatments relative that of control. Lactobacillus treatments showed improved tendency in crude ash and fat compared to those of control, whereas phosphorus digestibility was not consistency. Nutrients digestibilities of bird fed LCH were superior to those of other treatments, It showed significantly higher in Ca and P digestibility than control(P〈0.05). Total Lactobacillus spp. of birds fed various Lactobacillus was significantly higher in illeum for five weeks(P〈0.05), but was not different at cecum. Yeast was thought to be not completely attached to intestinal lumen for one week. However, total number of yeast was significantly increased in cecum and illeum of three weeks old chicks (P〈0.05). The number of anaerobes exhibited to tendency the increase in Lactobacillus treatments from one week old of age at both ileum and cecum.

• Journal of Chest Surgery
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• v.36 no.7
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• pp.539-543
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• 2003

Langerhans cell histiocytosis (LCH), previously called histiocytosis X, refers to a spectrum of disease characterized by idiopathic proliferation of histiocytes producing focal or systemic manifestations. Causes and pathogenesis remain unclear The basic histopatholgic fndings are identical in the three well-established clinical syndromes (eosinophilic granuloma, Hand-Shuller-Christian disease, Letterer-Siwe disease). The disease has a predilection for children, although it may occur in adults. We experienced two cases of adult onset Langerhans cell histiocytosis in the ribs. One case was associated with diabetes insipidus and the other case had a solitary lesion.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.408-416
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• 2002

Hydraulic performance of the pump with an inducer was predicted by 3-D Navier-stokes calculation. The evaluated pump was the single-stage centrifugal pump with a separated inducer to pressurize fuel (LCH4) in Turbo-pump system with a specific speed (Ns) of approximately 0.3[rad/s, m3/s, J/kg] and a suction specific speed(s) of 15[rad/s, m3/s, J/kg]. That conventional pump was designed with the combination of 1-D theory and empirical correlation. In this study, preliminary design to select key parameters such as inlet flow coefficient was reviewed by investigating sets of the known design methods to achieve appropriate suction performance, and the performance of newly designed inducer and impeller was compared with the old one, using CFD method. The numerical results showed that the hydraulic efficiency of the new pump was predicted $5.5\%$ higher than that of the conventional one, through design parameter re-selection, configuration improvement and blade loading control

• Magazine of the Korea Concrete Institute
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• v.8 no.1
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• pp.130-137
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• 1996

본 연구는 정적 및 동적하중 재하상태에서 배합조건을 달리한 콘크리트의 파괴특성을 조사하고자 3점 휨 실험을 실시하였다. 실험은 물-시멘트비를 일정하게 유지한 상태에서 슬럼프 값을 변화시키는 경우와 슬럼프 값을 일정하게 유지하면서 물-시멘트비를 변화시키는 경우로 구분하여 배합비를 달리한 6가지 배합형태의 무근콘크리트 시편 54개를 제작하였다. 실험결과에 의하여 콘크리트의 파괴에너지(Gf)와 특성길이(lch)를 구한 수 이를 강도특성(f'c, fsp , Ec, ff)과의 상관관계를 규명하고 파괴에너지(Gf)를 이용한 배합설계의 타당성을 검토하였다.

• Journal of the Korean Society of Systems Engineering
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• v.13 no.1
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• pp.7-14
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• 2017

Korea Aerospace Research Institute takes part in the vibration control software development for an Active Vibration Control System (hereafter, AVCS) for helicopters with Korea Aerospace Industries Ltd. in the Light Civil Helicopter (LCH) Project. The vibration control software is being developed per RTCA/DO-178C certification regulation and use of configuration management tools for software outputs is required. Redmine, an open source software is for issue or bug tracking and management software. Git, another open source software is a distributed version control software and is developed for Linux OS development. This paper introduces the functionalities of Redmine and Git, the reason why they are selected for the configuration management tool for the software outputs, and how they are being used for AVCS software development.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.235-242
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• 2001

Hydraulic performance of LCH4 fuel inducer in turbopump system was predicted by 3-D Wavier-stokes calculation. The inducer was designed initially using 1-D method. Different parameters with blade angle and flow coefficient were set from the initial design one, md computation was fulfilled to assess the redesigned models. Especially, influence of inlet back flow on inducer performance and its effective control were explored. The numerical results showed that through reducing inlet back flow strength., the hydraulic efficiency of inducer could be improved up to about $20\%$ compared to that of the initial design one.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.60
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• pp.47-55
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• 2000

Two experiments were conducted to examine the relationships between the color structure and the user preference of a CNS (Car Navigation System) digital map in terms of HSE (Human Sensibility Ergonomics). In the first experiment, the user's preference of color structures were investigated from the subjects' self-designed digital maps using a CNS digital map UIMS (User Interface Management System): in the second, statistical relation models between the user's color structure satisfaction level and the color components of CIE (Commission Internationale de ι'Eclairage) of the real products were suggested. For each experiment, CIE L*u*v* and CIE LCH color space were adapted, respectively, because they have their own characteristics of perceptual uniformity which enables the color components to transform a linear function.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.3
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• pp.167-172
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• 2019

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by the proliferation of dendritic cells resulting in local or systemic symptoms. The clinical symptoms of patients with Langerhans cell histiocytosis depend on the site and the degree of involvement. This article describes two case histories of unifocal bony Langerhans cell histiocytosis with mandibular involvement and further discusses the appropriate management of such via a review of the literature.