[구조강도부문] ZZ-SPR을 이용한 Pollution Error의 추정에 관한 연구

편수범(Soo-Bum Pyun),유형선(Hyeong-Seon Yoo) 한국자동차공학회 1999 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

In this study we focus on the estimation for the pollution error by using ZZ-SPR. simply denoted as Zienkiewicz & Zhu Superconvergent Patch Recovery. The error resulted from the conventional error estimators is equivalent to the local error. Moreover. in the case of unsmooth solution problem with a polygonal domain such as L-shape. the local error estimates are much smaller than the pollution error ones. Therefore. the estimation of the pollution error as well as the pollution adaptive mesh has a large effect on the accuracy of the solution. Thus we use the ZZ-SPR for estimating the pollution error. Subsequently. we emphasize on the necessity for calculation of the pollution error by comparing the pollution error estimate with the local one.

Synthesis of ZnO nanotubes and nanotube-nanorod hybrid hexagonal networks using a hexagonally close-packed colloidal monolayer template

Pyun, Yong Bum,Yi, Jaeseok,Lee, Dong Hyun,Son, Kwang Soo,Liu, Guanchen,Yi, Dong Kee,Paik, Ungyu,Park, Won Il Royal Society of Chemistry 2010 Journal of materials chemistry Vol.20 No.24

<P>We present a new synthetic approach, <I>via</I> hydrothermal process with the use of polystyrene (PS) colloids, to fabricate vertically aligned, single crystalline ZnO nanotube arrays. Electron microscopy images revealed that single crystalline nanotubes with inner diameters of ∼15–20 nm and wall thicknesses of ∼10–15 nm were formed just below the PS colloids, whereas solid nanorods were grown in the absence of PS colloids. In addition, nanorods enclosing the PS colloids exhibited much faster growth rates than those on the area not covered with PS colloids. These results indicate that the introduction of PS colloids affected the formation and diffusion of adatoms. The growth behavior of ZnO crystals with regards to the PS colloids was exploited to convert the ZnO nanostructures from solid to nanotube-nanorod hybrid networks by introducing hexagonally close-packed PS colloidal monolayers. Moreover, we demonstrated further conversion to complete tubular forms by reducing the aperture size between adjacent PS colloids with thermal annealing.</P> <P>Graphic Abstract</P><P>A new synthesis route to fabricate vertically aligned ZnO nanotubes and nanotube-nanorod hybrid structures <I>via</I> wet hydrothermal processes with the use of polystyrene colloids deposited on ZnO seed layers is demonstrated. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0jm00011f'> </P>

쇄골하동맥 스텐트 삽입술의 조기결과

편욱범,윤영섭,최동훈,장양수,심원흠 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.5

기존제품과 신제품의 판매 공존을 고려한 신제품 개발 통합모델

Je Bum Pyun,Dae Soo Kim,Myung Sub Park 한국경영학회 2014 한국경영학회 통합학술발표논문집 Vol.2014 No.8

Decision making for new product development (NPD) is essential for a firm’s survival and growth in the competitive market. This research examines the situation in which the current product``s performance is improved incrementally and there is some periods of selling both existing and new products for a period between time-to-market for a new product and end-of-life for the existing product. We develop an integrated analytical model to simultaneously determine important factors in NPD, including the price of a new product, its level of performance, development resources input, and time-to-market, along with end-of-life for the existing product in order to maximize profit during the development and sales period. Then we solve optimally the model which involves complex tradeoffs among the decision variables, using LINGO. Through sensitivity analyses, we provide important theoretical and managerial implications on NPD.

Battery Materials : ELECTROCHEMICAL STUDY OF ZINC DEPOSITION ON NEGATIVE ELECTRODE DURING CHARGING THE Ni - Zn SECONDARY BATTERIES : SUBSTRATE EFFECT

Hyuk Chang,Young Bum Pyun,Young Soo Son 대한금속재료학회 ( 구 대한금속학회 ) 1995 Advanced Material and Processing Vol.2 No.-

Controlled synthesis and optical transmission characteristics of silicon nanowires on colloid patterned glass substrates

Dong Hyun Lee,Yong Bum Pyun,Kwang-Soo Son,Jae-Woong Choung,이정민,Seong Jun Son,박원일 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.1

We report the patterned synthesis of silicon nanowire (SiNW) arrays by controlling the density and position of Au colloids on glass substrates in a nanocolloid-catalyzed chemical vapor deposition (CVD) process. Density-controlled colloidal Au patterns were defined on the substrates by an inverse contact imprinting technique, where the strong attractive force between electrolyte-coated polymer stamp surfaces and Au colloids was exploited for selective removal of Au colloids from contacting regions of the substrate to the stamp. Controlled nanocolloid-catalyzed CVD process led to the growth of SiNWs being rooted in the catalytic patterns and extended over several tens of μm. In addition, optical transmittance of the SiNW pattern arrays depending on the NW density and the coverage of catalytic patterns were investigated to understand the optical properties of SiNW arrays.

An Event Study of the Effect of New Product Development on Stock Price in China

이병(Bing Li),편제범(Je bum Pyun),김대수(Dae Soo Kim) 한국생산관리학회 2015 韓國生産管理學會誌 Vol.26 No.1

신제품 개발은 업계와 학계에서 중요한 이슈로 여겨져 왔다. 하지만 신제품 개발이 기업의 재무성과에 미치는 영향에 관해서는 여러 이견들이 있다. 나아가 이 이슈에 관해서 선진국과는 다른 특징을 보일 수 있는 개발도상국을 대상으로 한 연구는 미미하다. 따라서 본 연구는 신제품 개발이 기업의 재무성과(주가)에 미치는 영향과 개방형 혁신의 주요 요소인 공급사 협력이 신제품 개발에 미치는 상승 효과에 대해서 분석하였다. 이를 위해, 글로벌 금융위기가 발발하기 전의 7년 간 중국 주식시장에서 신제품 개발 발표를 한 81개의 상장기업 데이터를 이벤트 연구방법을 사용하여 분석하였다. 그 결과, 대상기업 59%가 주가에 긍정적 영향을 보였고, 신제품 개발에서 공급사 협력이 주가에 유의미한 상승 작용은 하지 않는 것으로 나타났다. 이와 관련하여 사후 분석을 하였고 이론적, 실무적 시사점과 더불어 향후 연구 방향을 제시하였다. New product development (NPD) has long been a crucial issue in practice and academia. Regarding its effect on firms' financial performance, however, controversial arguments exist. Moreover, there is little research investigating this issue in developing countries, which may be different in developed countries. Therefore, we intend to examine two key issues of NPD: 1) whether NPD leads to positive financial performance (stock price) and 2) whether supplier collaboration, a key element of open innovation, enhances the effect of NPD on stock price. Using the event study method, we analyzed the data collected from 81 publicly traded companies in China, which announced NPD over the seven-year period before the global financial crisis. The analysis results indicated that 59% of the companies exhibited an increase in their stock price with positive mean abnormal return and that supplier collaboration in NPD did not significantly affect stock price. Along with post-hoc analyses, we provided theoretical and managerial implications with future research directions.

Pollution 오차를 이용한 요소생성에 관한 연구

유형선(Yoo Hyeong Seon),편수범(Pyun Soo Bum) 한국철도학회 1999 철도저널 Vol.2 No.3

In this paper, made was a study on a mesh generation method based on the pollution error. This method is designed for the control of the pollution error in any patch of elements of interest. It is a well-known fact that the pollution error estimates are much more than the local one. When the pollution error is significant, nothing can be said about the reliability of any estimator based on local computations in the patch. Reliable a posteriori error estimation is possible by controlling the pollution error in the patch through proper design of the mesh outside the patch. This design is possible by equally distributing the pollution error indicators over the mesh outside the patch. The mesh generated from the conventional feedback pollution-adaptive mesh generation algorithm needs many iterations. Therefore, the solution time is significant. But the remeshing scheme in the proposed method was used here. It was shown that the pollution-adaptive mesh improves the E.I., simply denoted as Effectivity Index, on the patch of interest, and the pollution error reduces less than the local error.

급성 심근 경색으로 발현된 다발성 결절성 동맥염 1예

장혁재,윤영섭,편욱범,심원흠,최성희,박용범,이수곤,김병극 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.2

단독 좌전하행관동맥 질환의 치료에서 약물치료 , 풍선확장술 , 스텐트삽입술간의 비교관찰

조승연(Seung Yun Cho),장양수(Yang Soo Jang),이동일(Dong Il Lee),편욱범(Wook Bum Pyun),최동훈(Dong Hoon Choi),심원흠(Won Heum Shim) 대한내과학회 1999 대한내과학회지 Vol.57 No.5

N/A With recent advances in transarterial interventional technique, there is a tendency to treat single LAD lesion with balloon angioplasty or stent insertion rather than with medical therapy alone. Therefore, it is important to evaluate the long-term clinical outcomes of such interventional therapy. Methods : Subjects are comprised of patients who underwent coronary angiogram from 1993 to 1996 and diagnosed as having single LAD lesion without decrease of left ventricular fuction. The incidence of major ischemic complications, revascularization and reduction of angina pectoris after different therapeutic strategies in these patients are evaluated. Result : 1) There was total of 190 patients. Patients receiving medical therapy, balloon angioplasty and stent insertion were 70, 75, and 45 respectively. There was no significant difference in mean age, sex ratio, and risk factors of coronary artery occlusive disease between each groups. 2) The medical therapy group(30%) had a significantly lower incidence of proximal stenosis lesion compared to the balloon angioplasty group (45%) and stent insertion group(52%) according to the location of the lesion(p<0.05). The lesion characteristics according to the AHA/ACC criteria showed that the proportion of type A lesion was significantly higher in the balloon angioplasty group(33.3%) compared to the medical therapy group(8.6%) and stent insertion group(13.3%), whereas the proportion of type C lesion was significantly higher in the medical therapy group(41.4%) compared to the balloon angioplasty group(14.3%) and stent insertion group(22.2%). 3) The incidence of ischemic complication were low with 9 out of total 190 patients during follow up consisting of 2 cases of cardiogenic death(1.1%) and 7 cases of acute myocardial infarction(3.7%). 4) During the follow-up period revascularization was performed in 10% of medical therapy group, 27% of balloon angioplasty group and 22% of stent insertion group. There was higher rate of revascularization in patients who received interventional therapy. 5) During the mean follow-up period of 38 months, event-free survival rate was 85% in the patient group receiving medical therapy, 71% in the patient group undergoing balloon angioplasty and 74% in the patient group undergoing stent insertion. There was lower incidence of major events in medical therapy patients, but the difference of the rate among each group was not significant. In considering the patients with proximal LAD stenotic lesion, event-free survival rate was 73% in medical therapy group, 75% in balloon angioplasty group and 81% in stent insertion group, but the difference between each groups did not show any significant difference. 6) Follow-up of each study groups at 6 months, 1 year and 3 years showed that the proportion of chest pain-free patients in balloon angioplasty and stent insertion group were higher than those in medical therapy group despite the lack of statistical significance(p>0.05). Conclusion : For patients with single LAD stenotic lesion interventional therapies such as balloon angioplasty and stent insertion might be more effective without statistical signigicance in reducing chest pain compared to medical therapy. There was no significant difference in the incidence of ischemic complication and rate of revascularization among different study groups. Further studies will be needed to clarify the beneficial effects of interventional coronary artery therapy such as improvement of chest pain, increased exercise capacity, and improved quality of life along with other parameters. (Korean. J. Med 57:896-905, 1999)