산화물 혼합상이 페라이트계 P/M스테인리스강의 고온산화 및 전기저항 안정성에 미치는 영향

박진우,고병현,정우영,박동규,안인섭,Park, Jin-Woo,Ko, Byung-Hyun,Jung, Woo-young,Park, Dong-Kyu,Ahn, In-Shup 한국분말야금학회 2016 한국분말재료학회지 (KPMI) Vol.23 No.3

In order to improve the high-temperature oxidation stability, sintered 434L stainless steel is studied, focusing on the effect of the addition of metallic oxides to form stable oxide films on the inner particle surface. The green compacts of Fecralloy powder or amorphous silica are added on STS434L and oxidized at $950^{\circ}C$ up to 210 h. The weight change ratio of 434L with amorphous silica is higher than that of 434L mixed with Fecralloy, and the weight increase follows a parabolic law, which implies that the oxide film grows according to oxide diffusion through the densely formed oxide film. In the case of 434L mixed with Fecralloy, the elements in the matrix diffuse through the grain boundaries and form $Al_2O_3$ and Fe-Cr oxides. Stable high temperature corrosion resistance and electrical resistivity are obtained for STS434L mixed with Fecralloy.

P/M Fecralloy 성형체의 고온산화 및 전기저항 안정성에 미치는 SiO₂ 첨가 효과

박진우,옥진욱,정우영,박동규,안인섭,Park, Jin-Woo,Ok, Jin-Uk,Jung, Woo-young,Park, Dong-kyu,Ahn, In-Shup 한국분말야금학회 2017 한국분말재료학회지 (KPMI) Vol.24 No.4

A metallic oxide layer of a heat-resistant element contributes to the high-temperature oxidation resistance by delaying the oxidation and has a positive effect on the increase in electrical resistivity. In this study, green compacts of Fecralloy powder mixed with amorphous and crystalline silica are oxidized at $950^{\circ}C$ for up to 210 h in order to evaluate the effect of metal oxide on the oxidation and electrical resistivity. The weight change ratio increases as per a parabolic law, and the increase is larger than that observed for Fecralloy owing to the formation of Fe-Si, Fe-Cr composite oxide, and $Al_2O_3$ upon the addition of Si oxide. Si oxides promote the formation of $Al_2O_3$ and Cr oxide at the grain boundary, and obstruct neck formation and the growth of Fecralloy particles to ensure stable electrical resistivity.

타당성 평가가 보완된 모델 운용상의 전투실험 모의분석 절차 연구

박진우,김능진,강성진,서혁,Park, Jin-Woo,Kim, Nung-Jin,Kang, Sung-Jin,Soo, Hyuk 한국시뮬레이션학회 2010 한국시뮬레이션학회 논문지 Vol.19 No.4

Currently, our society has been changed from the industrial society to the information society. As the war progresses to Information Warfare, Network-Centric Warfare, Long-Range Precision Engagement and Robot Warfare, the military should advance to High-tech Scientific force. For this creation of the war potential, it is regarded as the warfighting experiment is a critical method. Surely it is rational that LVC(Live Virtual Constructive simulation) is desirable to make the warfighting experiment. But because it is limited by the cost, the time, the place and the resource, the constructive simulation(M&S : Modeling&Simulation) is a good tool to solve those problems. There are some studies about the evaluation process for developing the model, but it is unsatisfying in the process of the constructive simulations' operation. This study focuses on the way of constructive simulation operation, which is supplied with the evaluation process(VV&A : Verification Validation & Accreditation). We introduce the example of the rear area operation simulation for "appropriateness evaluation to the organization of logistic corps" by the AWAM(Army Weapon Analysis Model). This study presents the effective methods of the constructive simulations, which is based on the reliable evaluation process, so it will contribute to the warfighting experiments.

P/M Fecralloy의 성형성 및 전기저항특성 향상에 관한 연구

박진우,고병현,정우영,박동규,안인섭,Park, Jin-Woo,Ko, Byung-Hyun,Jung, Woo-Young,Park, Dong-Kyu,Ahn, In-Shup 한국분말야금학회 2016 한국분말재료학회지 (KPMI) Vol.23 No.6

The Fe-Cr-Al alloy system shows an excellent heat resistance because of the formation of an $Al_2O_3$ film on the metal surface in an oxidizing atmosphere at high temperatures up to $1400^{\circ}C$. The Fecralloy needs an additive that can act as a binder because of its bad compactability. In this study, the green compacts of STS434L and Al powder added to Fecralloy are oxidized at $950^{\circ}C$ for up to 210 h. Fecralloy and Al is mixed by two types of ball milling. One is vented to air and the other was performed in a sealed jar. In the case of Al addition, there are no significant changes in the electrical resistance. Before the oxidation test, Al oxides are present in the Fecralloy surface, as determined from the energy dispersive spectroscopy results. The addition of Al improves the compactability because of an increased density, and the addition of STS434L increases the electrical resistivity by forming a composite oxide.

자주식 휠체어 접근성 실태에 기반한 대학 건물 3차원 접근성맵 제작 - 충북대학교 사례를 중심으로 -

박진우,이예지,이현정,Park, Jin Woo,Lee, Ye Ji,Lee, Hyun-Jeong 인천대학교 도시과학연구원 2021 도시과학 Vol.10 No.1

The purpose of this study was to evaluate accessibility condition of buildings in a college from manual wheel chair users' perspective in order to suggest improvements, and to develop 3D accessibility maps in order to assist manual wheelchair users' prior planning for the building use. In May 2020, on-site investigation was held to three buildings in Chungbuk National University. Major findings were as follows. (1) There were some building entrances that showed level difference over 2cm without proper ramp with slow slope 1/8 or less. (2) Some rooms were found to have accessibility issues to have floors with height more than 2cm, and/or to have no height-adjustable desks. (3) Although accessible restrooms were in good condition for manual wheelchair users' access and use, it is suggested to install accessible restroom for each gender in each floor for better access. Using the study results, 2-dimensional accessibility maps for each floor were developed in color and grayscale, which were further developed into 3-dimensional accessibility maps for each building.

Uroskinase 에 의한 항응혈반응에 관한 연구 Ⅰ. Urokinase 의 정제와 효소 특성

박진우,이현재,김수자 ( Jin Woo Park,Hyun Jae Lee,Soo Ja kim ) 생화학분자생물학회 1980 BMB Reports Vol.13 No.3

The activation of plasminogen to an active fibrinolytic enzyme, plasmin, was studied withe urokinase(EC 3. 4. 26. 99). A crude form of urokinase obtained from human urine was purified partially by an ion exchange column of ECTEOLA and further by an affinity column employing arginine or agmatine as a ligand on Sepharose 4B matrix. The specific activity of the final enzyme preparation was about 1, 300 units per ㎎ protein based on the caseinolytic assay measuring the rate of casein hydrolysis by plasmin formed. The mode of the enzyme action seems to be similar to that of trypsin in term of the esterase activity, but the enzyme is found to be very specific toward plasminogen as the substrate. Characteristic properties of the enzyme including molecular weight, pH and temderature optimum, and some kinetic properties were studied and compared with that of the other proteolytic enzyme of trypsin and plasmin. In addition, based on its associative properties, the nature and the physiological role in the fibrinolysis were also discussed.

Plasminogen 활성제로서의 Urokinase 의 활성화 부위내 작용기들에 대한 연구

박진우,김수자,이현재 ( Jin Woo Park,Soo Ja Kim,Hyun Jae Lee ) 생화학분자생물학회 1983 BMB Reports Vol.16 No.2

In order to elucidate the mechanism of the urokinase- induced plasminogen activetion, catalytically active functional groups which involved in the active site of urokinase molecule were investigated by a series of kinetic and chemical modification experiments. Inhibition study with several lysine and arginine derivatives indicates there involves hydrophobic interaction between urokinase and plasminogen molecules. 6-Amino hexanoic acid shows an exceptional high degree inhibition. The results from a set of pH-activity profiles and several chamical modification experiments suggest there involve at lease one serine hydroxyl moiety and one histidine imidazole group in the active site of the activator urokinase for the catalytic conversion of plaminogen into plasmin. Based on the results obtained, a minimal three step mechanism of the UK-induced plasminogen activation process was proposed as a working model.

갑상선 종양의 발병 기전

박진우,Jin-Woo Park 대한갑상선-내분비외과학회 2010 The Koreran journal of Endocrine Surgery Vol.10 No.2

Thyroid tumors display an intriguing biological diversity from benign follicular adenomas to lethal anaplastic carcinomas. Thyroid tumorigenesis is becoming better understood. Benign follicular adenomas are frequently associated with mutation of the thyrotrophin receptor, G alpha s or RAS. Although confirmatory studies are necessary, the present knowledge concerning the similarity in gene expression profiling between follicular adenomas and follicular carcinomas supports the progression of adenoma to carcinoma sequence. Four major genetic aberrations in follicular cell- derived thyroid carcinomas such as papillary, follicular, and Hurthle cell carcinomas include mutations of BRAF or RAS, and chromosomal rearrangement of RET/papillary thyroid tumor or PAX8/peroxisome proliferator-activated receptor gamma. Differentiated thyroid carcinomas of follicular cell origin dedifferentate to poorly differentiated or anaplastic thyroid carcinomas through mutation of p53 and CTNNB1. Familial nonmedullary thyroid carcinomas are heterogenous in genetic profiling, but some genes have been investigated as candidates for causative genetic aberration. Ret mutations can cause medullary thyroid carcinomas. A genotype-phenotype relationship helps to decide prophylactic thyroidectomiesin family members of hereditary medullary carcinomas such as MENIIa or MENIIb. Primary thyroid lymphomasare closely related with Hashimoto's thyroiditis. Recent novel and promising findings include additional abnormalities in the regulation of microRNA expression, polymorphisms associated with thyroid cancer susceptibility and epigenetic changes. A newly proposed fetal cell carcinogenesis hypothesis explains more about thyroid tumorigenesis than classical multi-step carcinogenesis model, but is not yet firmly supported by evidence. Future studies need to uncover new molecular mechanisms in thyroid tumorigenesis and to provide novel therapeutic targets for thyroid carcinomas. (Korean J Endocrine Surg 2010;10:79-87)

국방 물류비용 추정 모델에 관한 연구 - 육군 피복류 중심으로 -

박진우,강성진,Park, Jin-Woo,Kang, Sung-Jin 한국국방경영분석학회 2006 한국국방경영분석학회지 Vol.32 No.2

시장의 산업 구조가 더욱 복잡해지고 세계화가 급속도로 진행됨에 따라 현대 시장에서 물류에 대한 관심은 점점 커지고 있으며, 기업에서는 상품의 원가 절감을 위해 많은 노력을 기울이고 있다. 하지만 물류비용 추정에 대해서는 계산이 복잡하여 대부분 수송 비용을 중심으로 단순화한 선형적인 방법을 사용하고 있으며, 특히 군에서의 물류비용에 관한 연구는 매우 희박한 실정이다. 따라서 본 연구에서는 국방 물류비를 정의하고, 물류비의 구성 및 물류네트워크에 파라 물류비용에 대한 정량화된 정보를 제공할 수 있는 일반적인 모델을 제시하였다. 그리고 이 모델을 군의 주요 피복품인 전투화에 적용하여 군에서의 물류비가 구성 비율에 있어 일반 기업과 어떤 차이가 있는가를 비교 분석하고, 효과적인 비용 절감 방안을 제시할 수 있었다. 본 연구는 군의 물류비용 추정 및 군의 물류 의사 결정에 직접 지원되어 국방 예산의 효율적 운영에 기여할 것으로 기대된다. In modern marketing environment, we are more interested in logistics as industrial structure is complicated and globalized. Most companies focus on reducing the cost price. So a lot of companies study on cost estimation logistics. However, it Is very difficult to estimate the cost of logistics. Thus they mainly use linear method such as the simple distance of transportation. This study defines the cost of logistics, structure & network of military logistics and proposes the costing estimation model in the logistics. We apply to battle shoes which are the main clothing in the military. In the result, we found some differences on the rate of cost structure between military and civil companies. This study can be used directly to the decision making for optimal military logistics alternatives and contribute to the efficient operation of military budget.

탈단백 우골의 골이식 대체재로서의 특성에 대한 평가;세 종류의 골 대체재의 기본 특성에 대한 비교분석

박진우,Park, Jin-Woo 대한치주과학회 2005 Journal of Periodontal & Implant Science Vol.35 No.4

Bovine bone-derived bone substitutes are widely used for treatment of bone defects in dental and orthopedic regenerative surgery. The purpose of this study was to evaluate the basic characteristics of deproteinized bovine bone mineral as a bone graft substitute. Commercially available products from three different bovine bone minerals-Bio-Oss(GeistlichPharma, Switzerland), BBP(Oscotec. Korea), Osteograf/N-300(Dentsply Friadent Ceramed, USA) - were investigated. They were evaluated by scanning electron microscopy(SEM), energy dispersive X-ray spectrometer(EDS), surface area analysis(BET), and Kjeldahl protein analysis. Cell viability on different products was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay. The results of this study indicated that each bone substitute displayed distinct surface properties. Furthermore, Kjeldahl protein analysis indicated that residual crude proteins are present in deproteinized bovine bone mineral. BBP showed relatively large amount of residual protein, which indicated that the possibility of disease transmission can not be safely ruled out. Based on the results of this study, it is suggested that active quality management is strongly needed in operations that involve processing bovine bone tissue for medical use.