• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.482-485
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• 2002

200만호 주택건설로 폭발된 1980년대 주택건설 시장의 활성화는 수도권 및 신도시를 중심으로 많은 APT를 양산하였고 그 과정에서 품질수준은 물량 공급 위주의 주택정책으로 소비자의 욕구를 충족시키지 못하였고 준공된 건물에서는 예상치 못한 많은 하자를 발생시켰다. 이에 따라 $1980\~1990$년대 공동주택의 하자 예방을 위한 연구가 수행되어 하자 다발 공종과 분야별 빈도 및 하자 발생으로 인한 손실추정 등 여러 연구 성과가 축적되었으나 하자 발생율을 줄이고 하자로 인한 소비자의 불만족을 해소시키는데는 크게 기여하지 못하고 있다. 이는 하자 관련 연구가 실제 공사를 수행하는 시점에 적절히 관리하고 통제하는 SYSTEM과 연계되지 못하고, 제대로 적용되지 못하기 때문이다. 따라서 본 연구에서는 국내 건설공사 중에서 공통주택에서 발생하는 하자에 관한 정보와 현황에 대한 분석을 실시하고, 그 유형별 특성에 따른 분류를 실시한 뒤 이를 종합하여 체계적인 정보의 확보 및 활용을 위한 WEB 기반 FEED-BACK 시스템을 제안하고자 한다.

• 소성∙가공
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• 제11권2호
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• pp.165-170
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• 2002

The preform design of forging processes plays a key role in improving product qualities, such as defect prevention, dimensional accuracy and mechanical strengths. In the industry, preforms are generally designed by the iterative trial-and-error approach, but it results in significant tooling cost and time. It is thus necessary to minimize lead-time and human intervention through an effective preform design method. In this paper, the equi-potential lines designed in the electric field are introduced to find the preform shape, and then the optimization process is used to choose the equi-potential lines that will keep the die wear to a minimum Because, in the forging process, the die wear is a function of various important factors, such as forming stress and strain, microstructure and mechanical properties of a Product.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.2.1-2.7
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• 2018

With the development of computer-aided design/computer-aided manufacturing (CAD/CAM) technology, it has been possible to reconstruct the cranio-maxillofacial defect with more accurate preoperative planning, precise patient-specific implants (PSIs), and shorter operation times. The manufacturing processes include subtractive manufacturing and additive manufacturing and should be selected in consideration of the material type, available technology, post-processing, accuracy, lead time, properties, and surface quality. Materials such as titanium, polyethylene, polyetheretherketone (PEEK), hydroxyapatite (HA), poly-DL-lactic acid (PDLLA), polylactide-co-glycolide acid (PLGA), and calcium phosphate are used. Design methods for the reconstruction of cranio-maxillofacial defects include the use of a pre-operative model printed with pre-operative data, printing a cutting guide or template after virtual surgery, a model after virtual surgery printed with reconstructed data using a mirror image, and manufacturing PSIs by directly obtaining PSI data after reconstruction using a mirror image. By selecting the appropriate design method, manufacturing process, and implant material according to the case, it is possible to obtain a more accurate surgical procedure, reduced operation time, the prevention of various complications that can occur using the traditional method, and predictive results compared to the traditional method.

• 한국주조공학회지
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• 제21권5호
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• pp.280-285
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• 2001

Nb-containing austenitic stainless steel is widely used as exhaust frame and diffuser assembly in power plant. However, this steel is known to be difficult to produce by the continuous casting process due to the surface cracks. Therefore, the continuous casting technology was developed for the prevention of the surface cracks on CC slabs. Precipitates and the analysis of heat trasfer in a slab were investigated in order to find out the formation mechanism of surface cracks on cc slabs It was found that surface cracks are occurred due to the NbC precipitates, which are formed along the grain boundaries around $800^{\circ}C$. The secondary cooling pattern has been developed to produce the defect free CC slabs of Nb-containing austenitic stainless steel.

• 대한안전경영과학회지
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• 제10권3호
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• pp.99-107
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• 2008

Product liability(PL) is the producer's compensation to customers for damage incurred by product defects. This paper studies on the organizational culture, promotion process, system construction, system level, product safety review, product safety assurance, system operation, and its effectiveness and necessity of recognition for the PL system of small and medium-sized firms in Gangwon-Do province. The results show that the firms have product safety regulations, but the number of firms which its employees understand the regulations is less than the number of firms which do not understand. Also the number of firms which is preparing PL prevention and insurance, and counterplan for accidents seems to be not in large numbers.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제11권1호
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• pp.117-129
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• 1989

The commercial availability of processed heterogenous bone has provided the surgeons with almost unlimited supply, avoidance of additional operation and prevention of the postoperative complications. In addition to these merits, unnecessary bone bank, easy availibility and storage have been achieved. The purpose of this study was to compare and examine the healing capacity of Kiel bone, Pyrost and Osteovit which used as the processed heterografts for the reconstruction of bony defect. Twenty rabbits weighing about 1.7-2.0 Kg were selected and divided into two groups. In experimental group A, the left mandibular defect was allowed to fill with blood, and the right defect was filled with Kiel bone. In experimental group B, the left defect was grafted with Pyrost, and the right with Osteovit. The experimental animals were sacrified after 1, 2, 4 and 8 weeks and the grafted site was studied histologically. To evaluate the strength of healed bone, 2 rabbits from each experimental group and a nonoperated control were sacrified at the 6th week after implantation and used for biometric testing on universal testing machine. The results obtained were as follows : 1. It was considered that these heterogenous bone grafts has feeble or absent immunogenicity since all of them appeared to evoke little inflammatory or forign body reaction. 2. In all experimental groups, new bone formation began from the adjacent region of host bone and extended progressively into the defect sites. New bone was partly formed within the intertrabecular space of the implant and gradually united with the bone that formed at the margin of the host bone. 3. With Pyrost bone formation was rapid and prominent comparing with other graft materials. 4. Osteovit was begun to be absorbed from 2 weeks, and Kiel bone from 4 weeks, however Pyrost was remained to be intact until the end of 8 weeks. 5. As the results of tensile test, the mean values of maximum tensile stress were 1.11${\uparrow}$ $Kgf/mm^{2}$ in Pyrost implanted specimens, 0.85 $Kgf/mm^{2}$ in Osteovit, 0.42 $Kgf/mm^{2}$ in Kiel bone, 0.66 $Kgf/mm^{2}$ in blood filled specimens and 1..13 $Kgf/mm^{2}$ in control. These results indicate that heterogenous bones grafted have little antigenicity to the host tissue, and that they mediate effectively osteoconduction by providing the scaffold for the bone formation. Pyrost and Osteovit appeared to be suitable for the clinical use.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.258-259
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• 2017

As the use of advanced quality materials in constructions has been increasing since 1980 with the improvements in the quality of life and economic scale, there has been drastic increase in constructions using stones for the internal and external construction materials. However, the reality is where many problems rise due to improper construction and management of uncertified stones which shorten the expiry date of the stones and act as the factor causing defects in buildings. Such defects not only bring economic losses but also influence consumer choice and act as risk factors to demand expansion of stone market. Therefore, the object of this study lies on proposing plans to prevent personal and economical losses due to repetitive defects by deriving the types of defects generated by process in stone constructions and identify the causes. Also, proposing construction process management plans as the measure for defect prevention, analyzing problems of stone constructions followed by the whole proves of design, construction and maintenance of stones, and solving such problems through appropriate participation of professional consultants depending on situations.

• 대한치과의사협회지
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• 제54권4호
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• pp.274-283
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• 2016

Bisphosphonates are widely used mainly for the treatment of osteoporosis and bone metastasis of malignancy. Since the first report of MRONJ, there have been many studies associated, however the pathogenesis of MRONJ is not yet clear. Medication-related osteonecrosis of the jaws (MRONJ) is a serious complication associated with long-term medication therapy. It is characterized by exposed necrotic bonein the jaw, which has persisted for more than 8weeks despite continuous treatment by dentist. The mechanism of development of MRONJ is still unclear and there is no definitive standard treatment for MRONJ. The purpose of this study is to investigate the jaw bone destruction mechanism of accumulated bisphosphonates, so that we can develop therapeutic method to repair the defect and stop the destruction process. The authors performed simultaneous application of PRF(Platelet rich fibrin) and BMP-2(Bone morphogenetic protein-2) to stimulate not only soft tissue healing but also osseous regeneration. Our case series demonstrate that simultaneous application of platelet rich fibrin and bone morphogenetic protein-2 can be a treatment of choice for MRONJ.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.525-526
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• 2007

Over-polishing is required to completely remove the material of top surface across whole wafer, in spite of a local dishing problem. This paper introduces the two-step CMP process using protective layer and high selectivity slurry, to reduce dishing amount and variation. The 30nm thick protective oxide layer was deposited on the pattern, and then polished with low selectivity slurry to partially remove the projected area while suppressing the removal rate of the recessed area. After the first step CMP process, high selectivity slurry was used to minimize the dishing amount and variation in pattern structure. Experimental result shows that two-step CMP process can be successfully applicable to reduce the dishing defect generated in over-polishing.

• 의료법학
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• 제16권2호
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• pp.197-225
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• 2015

이 글은 2015년 메르스 사태를 계기로 2015. 6. 20. 의료법과 감염병예방법의 관련 조항을 분석하고 그 문제점을 적시하여 입법론을 전개한 발표문을 바탕으로 한 것이다. 발표에서 우선 감염병 분류 체계의 합리화를 지적하였다. 이 지적은 발표 직후의 '개정법률'에서 반영되었지만 여전히 유형의 중복성을 제거하는 등 그 합리화를 위한 작업이 필요하다. 한편 감염병의 신고 내지 보고 체계에 관하여 신고 내지 보고의 의무자와 상대방 및 그 시기 등의 관점에서 합리화를 위한 입법적 조치가 필요함을 언급하였다. 감염병의 대응 조치로 도입의 필요성이 주장된 의료기관의 폐쇄에 관한 방역조치는 '개정법률' 제47조에서 반영되었다. 하지만 방역조치의 권한이 여전히 중앙정부와 지방정부에 병렬적으로 중첩적으로 분배되어 있다는 점은 문제이다. 그 권한 귀속의 합리화는 중앙정부로의 일원화에서 찾아야 하며, 그 논거와 함께 그 필요성을 지적하였다. 한편 역설한 점은 장관 등 중앙정부 기관장이 그러한 폐쇄 명령이나 격리 명령을 내리는 경우, 그로 인하여 의료기관이나 환자가 입은 재산상 손실의 전부 또는 일부를 국가가 전보해 줄 의무를 지도록 하는 규정이 필요함이다. 이는 권한 귀속과 연계되는 것인바, 방역조치의 권한 귀속 주체와 그 손실전보를 위한 재원의 관리주체가 일원화되어야 할 필요성을 역설하였다. 방역조치 권한의 실효성은 그 손실 전보의 보장이 담보하는 것이며 이는 국부(國富)의 차원에서 접근해야 한다는 점에서 중앙정부로의 일원화에 관한 입법론을 전개하였다. 나아가서 감염병으로 인한 개인이나 의료기관의 재산상 손실은 민법의 일반불법행위의 법리에 맡기는 것이 비합리적이라는 점을 논술하였다. 이 역시 중앙정부의 재정에 의한 전보와 고의 내지 미필적 고의가 인정되는 개인에 대한 국가의 구상권 행사로 민사 분쟁을 해결함이 피해자의 구제에 합리적인 이유를 들어서 입법론을 제시하였다. 이번 메르스 사태에 대한 향후 조사에서 개선이 필요한 내용이 더 밝혀질 수 있을 것이다. 그러한 논의에 따라 보다 합리적이고 구체적인 입법론이 전개되어야 할 것이다.