• 한국산학기술학회논문지
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• 제21권8호
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• pp.468-474
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• 2020

덕트는 FCU에서 생산된 냉난방 공기를 각 함 내 격실로 수송하기 위한 통로로 이용되는 통풍관을 의마한다. 덕트는 일반적으로 금속재질로 제작되고 있으나, 최근 함정에서는 금속 덕트의 단점을 보완하기 위하여 전투지휘실, 조타실, 음탐기, 조종실 등 주요 격실에 대하여 소음감소효과가 뛰어나고 격실 내에 공기를 골고루 전달할 수 있는 장점을 가진 천 덕트가 대체재로 사용되고 있다. 그러나 함정용 천 덕트는 성능요구조건이 엄격하여 국내에서 생산하지 못하고 있으며 해외에서 전량 수입하고 있는 실정이다. 이 연구에서는 천 덕트는 국산화를 통해 경제적 효과를 창출하기 위하여 국내 업체에서 개발한 천 덕트에 대하여 주요성능 요구조건을 검증하여 보았다. 소음감쇄성능에 대한 자체 검증이 완료된 국산화 천 덕트에 대하여 현재 건조중인 함정에 적용 가능여부를 확인하기 위해 공기투과성능과 방화성능 시험을 수행하여 구매요구사양서에 제시된 성능요구조건 충족여부를 검증하여 보았다. 시험결과 국산화 개발된 천 덕트는 공기투과성능 요구조건과 방화성능 요구조건을 모두 만족하여 건조함정에 적용하기 위한 주요 성능조건을 충족하는 것으로 확인되었다.

• 한국임상수의학회지
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• 제26권1호
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• pp.113-116
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• 2009

서울동물원의 4세령, 초산 그물무늬기린이 난산 상황에서 특별한 보정장치 없이 수컷 새끼기린을 분만하였다. 어미 기린은 7시간 이상 외음부에 새끼 기린의 앞발이 나온 상태에서 분만의 진전 없이 난산 위기에 처해 있었다. 외음부에 나온 태아 앞발 중수골에 로프 올가미를 한 후 잡아당겨 반대쪽 발목을 견인하였다. 한 개의 로프 올가미를 더 만들어 반대쪽 발목에 걸어 어미 기린의 자궁수축 리듬에 맞춰 로프를 잡아당겨 건강한 새끼 기린을 얻었다. 분만 후 어미 기린은 정상적으로 새끼를 돌봐주었고 분변 내 호르몬 수치를 검사한 결과 분만 후 프로제스테론 수치는 분만 전 상태로 떨어졌다.

• 대한화학회지
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• 제39권5호
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• pp.399-407
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• 1995

회토류와 악티늄족 원소의 현장분석을 목적으로 휴대용 극미량 분석용 원자 분광계인 Electrothermal-Hollow Cathode Glow Discharge Spectrometry(Et-HCGDS)가 제작되었다.본 분광계의 기본 구조는 전기열과 글로우 방전에 기초를 두고 있으며 본 분광계가 미량의 원소분석에도 유용함을 실험적으로 살펴보았다. 본 연구는 새로이 제작된 Et-HCGDS라는 글로우방전 시스템을 사용하여 공기의 저온 플라스마를 만들고 여기서 얻은 공기의 방출 스펙스럼에 관하여 연구하였다. 본 연구를 통하여 Et-HCGDS를 사용할시에 공기가 흐름가스로 유용하며 이 경우 대기의 분석도 쉽게 이루어질 수 있음을 알았다. 글로우 방전을 이용하여 관찰한 공기의 방출 스펙트럼의 분석을 통하여 볼 때 거의 질소에 의한 방출이 전 자외선과 가시광선 영역에서 골고루 나타남을 살펴보았다. 공기를 흐름가스로 사용할 시에도 여러파장 영역에서 미량 분석이 가능함을 알았다. 이 결과는 앞으로 Et-HCGDS를 사용하여 현장에서 공기만을 사용하여 분석을 수행할 경우에 필요한 기초 자료로 활용될 수 있으리라 본다. 본 연구에서 수행한 공기 방출 스펙트럼의 분석은 대기 분석 및 물질 분석에도 중요한 기초자료로 쓰이게 되리라 기대하며 이와 더불어 방출을 이용한 분광분석에서 공기로 인한 간섭 스펙트럼등을 이해하는 경우에도 중요한 참고자료로 활용되리라 본다.

• 한국패류학회지
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• 제27권3호
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• pp.159-165
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• 2011

개조개 소화맹낭의 해부학적 구조와 미세구조를 광학 및 전자현미경을 이용하여 기재하였다. 개조개는 한국 여수연안에서 2010년 5월에 채집하였다. 소화맹낭은 진한 녹색으로 생식소 위쪽에 위치하며, 일차소관으로 위와 연결되어 있었다. 소화맹낭은 다수의 소화선세관들로 구성되며, 각각의 소화선세관은 단층 상피층으로 호염기성세포와 소화세포들로 이루어져 있었다. 호염기성세포는 원주형으로 소화세포에 비해 전자밀도가 높았다. 세포질에는 잘 발달된 조면소포체, 관상의 미토콘드리아, 골지체 및 전자밀도가 높고 막을 가진 분비과립들을 함유하고 있었다. 소화세포는 원주형이며, 자유면에는 미세융모가 발달되어 있었다. 세포질 상부에서는 음소포, 용해소체 및 미토콘드리아가 관찰되었다. 본 연구에서 이러한 결과는 소화선세관의 호염기성세포와 소화세포는 각각 세포외 소화와 세포내 소화에 적당하게 분화되었음을 의미한다.

• 한국전문물리치료학회지
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• 제22권3호
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• pp.23-32
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• 2015

The purpose of this study was to identify the effects of mechanical traction applied to the knee joint on pain, knee range of motion (ROM), timed up and go (TUG) and Western Ontario and MacMaster Universities Osteoarthritis (WOMAC) in patients with knee osteoarthritis (KOA) of Kellgren-Lawrence radiological rating scale II or III. Twenty three patients participated in the experiment for a period of four weeks. After baseline assessment, the patients with KOA were randomized into two groups: the traction group ($n_1=12$), which received traction with general physical therapy; and the control group ($n_2=11$), which received general physical therapy only on unilateral knee joints. Patients received interventions once a day, three times a week, for four weeks. Wilcoxon signed-rank test was used to analyze the change of dependent variances within the group during pre and post intervention. Mann-Whitney U test was used to analyze the change of dependent variances as TUG and passive ROM between the two groups. Analysis of covariance was used to analyze the change of dependent variances as numeric pain rating scale (NPRS) and WOMAC score between the two groups. In Wilcoxon signed-rank test, the traction group improved significantly with regard to NPRS (p<.01), passive knee flexion ROM (p<.01), passive knee extension (p<.05), TUG (p<.01) and WOMAC scores (p<.01) after intervention for four weeks, but not for the control group. In the Mann-Whitney U test and analysis of covariance, no significant difference was seen among all the dependent variances after intervention for four weeks between the two groups. These outcomes suggest that further studies should be carried out to determine the effects of mechanical traction prior to using it for the treatment of patients with knee osteoarthritis.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권5호
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• pp.293-298
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• 2012

Purpose: The aim of this study was to evaluate the bone regeneration ability of 1% tetracycline (TC)-loaded silk fibroin membrane (SFM), in a rabbit calvarial defect model. Methods: Twenty New Zealand white rabbits were used for this study. Bilateral round defects were made on the rabbit parietal bone, using trephine bur with an 8 mm diameter. TC-loaded SFM or SFM was covered on the right parietal bone defect, and the left parietal bone defects were uncovered for the control. The animals were humanely sacrificed at 4 or 8 weeks postoperatively. A micro-computerized tomography (${\mu}$-CT) of each specimen was taken for analysis of bone regeneration. Hematoxylin and Eosin stain were done to observe histological findings. Results: From the ${\mu}$-CT results, regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $7.80{\pm}5.87$, $8.79{\pm}3.44$, and $10.61{\pm}5.3$ at 4 weeks postoperatively, respectively (P>0.05). Regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $36.56{\pm}8.50$, $25.86{\pm}8.17$, and $19.09{\pm}5.07$ at 8 weeks postoperatively, respectively (P<0.05). Conclusion: The 1% TC-loaded SFM showed more bone regeneration than the SFM and the uncovered control, in guided bone regeneration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권4호
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• pp.249-255
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• 2002

Recently, Skeletal Anchorage System (SAS) has been focused clinically with the view point that it could provide the absolute intraoral anchorage. First, it began to be used for the patient of orthognathic surgery who had difficulty in taking intermaxillary fixation due to multiple loss of teeth. And then, its uses have been extended to many cases, the control of bone segments after orthognathic surgery, stable anchorage in orthodontic treatment, and anchorage for temporary prosthesis and so on. SAS has been developed as dental implants technique has been developed and also called in several names; mini-screw anchorage, micro-screw anchorage, mini-implant anchorage, micro-implant anchorage (MIA), and orthosystem implant etc. Now many clinicians use SAS, but the anatomical knowledges for the installed depth of intraosseous screws are totally dependent on general experiences. So we try to study for the cortical thickness of maxilla and mandible in Korean adults without any pathologic conditions with the use of Computed Tomography at the representative sites for the screw installation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권4호
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• pp.250-254
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• 2010

Introduction: This study evaluated the bone regenerative effect of silk fibroin mixed with platelet-rich fibrin (PRF) of a bone defect in rabbits. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The silk fibroin mixed with PRF was grafted into the right parietal bone (experimental group). The left side (control group) was grafted only PRF. The animals were sacrificed at 4 weeks and 8 weeks. A micro-computerized tomography (${\mu}$CT) of each specimen was taken. Subsequently, the specimens were decalcified and stained for histological analysis. Results: The average value of plane film analysis was higher in the experimental group than in the control group at 4 weeks and 8weeks after surgery. However, the difference was not statistically significant.(P>0.05) The tissue mineral density (TMD) in the experimental group at 4 weeks after surgery was significantly higher than the control group.(P<0.05) Conclusion: Silk fibroin can be used as a scaffold of PRF for rabbit calvarial defect repair.

• 대한치과기공학회지
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• 제42권2호
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• pp.99-105
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• 2020

Purpose: A study analysed the stress distribution of abutment screw and supporting bone of fixture by the tightening torque force of the abutment screw within clinical treatment situation for the stability of the dental implant prosthesis. Methods: The finite element analysis was targeted to the mandibular molar crown model, and the implant was internal type 4.0 mm diameter, 10.0 mm length fixture and abutment screw and supporting bone. The occlusal surface was modeled in 4 cusps and loaded 100 N to the buccal cusps. The connection between the abutment and the fixture was achieved by combining three abutment tightening torque forces of 20, 25, and 30 Ncm. Results: The results showed that the maximum stress value of the supporting bone was found in the buccal cortical bone region of the fixture in all models. The von Mises stress value of each model showed 184.5 MPa at the 20 Ncm model, 195.3 MPa in the 25 Ncm model, and 216.5 MPa in the 30 Ncm model. The contact stress between the abutment and the abutment screw showed the stress value in the 20 Ncm model was 201.2 MPa, and the 245.5 MPa in the 25 Ncm model and 314.0 MPa in the 30 Ncm model. Conclusion: The increase of tightening force within the clinical range of the abutment screw of the implant dental prosthesis was found to have no problem with the stability of the supporting bone and the abutment screw.

• Clinics in Shoulder and Elbow
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• 제6권1호
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• pp.27-36
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• 2003

Antegrade interlocking intramedullary nailing (AIIN) for the humeral shaft fracture can induce shoulder pain and decrease of shoulder function postoperatively. The purpose of this study was to estimate the outcome of the shoulder functions after AIIN through the rotator interval between the subscapularis and the supraspinatus to decrease the shoulder pain. Out of consecutive 43 cases that underwent AIIN 42 had been followed for two years or more. Among them we analysized 40 cases of 39 Patients excluding two cases of Pathologic fractures. The average was 47 years. There were 17 men and 23 women. The average follow-up was 34 months. Open nailing was performed in 26 fractures and closed nailing in 14. Bone graft was done in 7 fractures with open nailing. With a single operation, all but two patients achieved osseous union. Average pain score with visual analog scale was one (range; 0∼4) postoperatively By the Neer's score 37 patients received a excellent or satisfactory results while 3 patients' unsatisfactory or failed results. By the functional score of ASES (American Shoulder and Elbow Society) 6 cases received the fair or poor results. Except three cases with persistent nerve palsy and one case of technique failure with protruded nail over humeral head, all patients could achieved satisfactory results with Neer's score and 35 cases (94%) satisfactory results with functional score of ASES. An insertion of antegrade nail to the rotator interval was recommended for better shoulder functions and less pain postoperatively.