• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.15-22
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• 1999

일반적으로 빌드업 다층 인쇄회로기판은 에칭, 도금등의 습식공정에 의해 제작이 이루어지므로 많은 장비와 많은 시간이 필요하게 된다. 이러한 습식공정은 양산에는 적합하지만 개발단계에서는 그리 적합하지 않은 방법이다. 본 연구에서는 스크린 인쇄기술을 도입하여 빌드업 다층 인쇄회로기판을 제작하여 보았다. 절연성 재료로는 광경화성수지 또는 열경화성수지를 사용하였으며 전도성 재료로는 전도성 페이스트를 사용하였다. 층간의 전기적 연결을 담당하는 비아와 회로를 형성하기 위해 스크린 인쇄공정을 통해 전도성 페이스트를 인쇄 하였다. 이러한 방법을 통해 제품의 개발 단계에서 기존의 빌드업 다층 인쇄회로기판 제작 공정과 비교하여 좀더 효율적인 방법을 제시하였다.

• 대한기계학회논문집B
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• 제22권6호
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• pp.813-822
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• 1998

The microexplosion of a slurry droplet was considered to be caused by the shell formation and the following pressure build-up in the shell which would be promoted by the suppression of evaporation, subsequent superheating and heterogeneous nucleation of liquid carrier. To closely investigate the pressure build-up and the heterogeneous nucleation, a numerical model was introduced by considering the internal temperature distributions with the shell formation, suppression of evaporation and pressure build-up inside. The microexplosion time was estimated by postulating the limit of superheat for heterogeneous nucleation. The simulation yielded a reasonably good agreement with experimental results for Al/n-heptane slurry droplets under various solid loadings.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.93-96
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• 2002

The manufacturing paradigm has shifted dramatically over the past decade from “push” or mass production mode to “pull” or customer-driven, order-based manufacturing mode, as multitudes of customers now demand mass customization of configurable products. As a means to achieve such rapidly responsive manufacturing system, Advanced Planning System (APS) has become an essential software tool for achieving modern “build-to-order” and “configure-to-order” manufacturing environment. APS enables manufacturers to respond to variety of customer demands In real time by instantly configuring manufacturing processes based on specifications described in each purchase orders and providing capable-to-promise information directly to customer by performing rapid “what-if” manufacturing simulated scenarios. This paper discusses the working of such system as well as the business processes that incorporate such systems to enable efficient “build-to-order” environment.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.114-118
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• 2004

This paper is compared the build time of scanning path as to laminate height of the SLC and STL file. The STL file improve the surface roughness according to slicing height. But it have the fault spending long time to the creation of scanning path by being lower slicing height. So we proposed the SLC file to improve this fault. Therefore this paper showed to the build time of scanning path by the increase of peace using the jewellery model.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.105-108
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• 1997

To reduce design period, demands for rapid prototyping system is increasing. Among the rapid prototyping system, as a concept modeler, 3D Printer appears before the footlights. In spite of short production time and convenience, 3D Printer causes post processing problem. And that is too slow to adapt to the demand of workshop. In this research, we developed a system for reducing build time and roughness using splitting operation. Also, propose BFS(B-rep For STL) data structure to maintain model data, split STL model and implement Euler Operation for input and output.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.101-104
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• 2002

Leading companies have embraced the new economy with new and innovative BTO models. Instead of conventional company-oriented manufacturing scheduling, customer-oriented scheduling method attracts more and more attention. To evaluate the delivery of customer order in advance, the real production capacity as well as procurement lead time should be taken into account. This paper describes a quasi-real-time order delivery estimation system using TOC(Theory of Constraints) based scheduling method.

• Journal of Ecology and Environment
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• 제29권1호
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• pp.69-74
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• 2006

The captive breeding biology of the Oriental white stork (Ciconia boyciana) was studied over 3 breeding periods. Both the male and female participated in nest building, but the male started to build the nest earlier and spent much time. Time used to build the nest was steadily increased to the egg laying. The copulations were observed $30{\pm}10.53$ (n=3) times in a breeding period. Both male and female incubated their eggs but the female spent more time than the male did. The chicks were hatched $32{\pm}1.29$ (n=6) days after egg laying. Not only the male but also the female took part in the rearing chicks. The male spent more time than the female as chicks grew. The results of this study are useful to assess the ecological soundness of the breeding pair and facilitate the breeding environment in captive breeding of the Oriental white stork.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.50-53
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• 2003

Most companies use technologies such as stereolithography, selective laser sintering, and fused deposition modeling to make parts for such small consumer products as telephones, heads, and shoes. The largest part that the existing RP systems can make is only 600 mm in length. Because most RP systems build parts by depositing, solidifying, or sintering material point-by-point, making larger objects takes a long time. and in many cases, large objects won't fit the build size. A new effective thick-layered RP process. Transfer type Variable Lamination Manufacturing using expandable polystyrene foam (VLM-ST) has been developed with thick layers and sloped surfaces. In this paper, a scaledown model of F16 Fighter with the length of 800 mm is rapidly fabricated using the VLM-ST process. In order to build a CAD model of F16 larger than 600 mm in length, the approach in VLM-ST is to build larger parts in multiple sub-parts and then glue them together. The fabricated result shows that the VLM-ST process employing thick layers and sloped surfaces is adequate for creating the real-sized large objects in the diverse fields such as automobiles, electric home appliances, electronics. and etc.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (2)
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• pp.276-278
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• 1998

근래 1,2년을 사이로 국내에서도 workflow system에 대한 인식이 높아지고, 실제 업무에 도입하려는 시도가 이루어지고 있다. 그러나, 아직까지는 실험적인 단계이며, 실질적인 적용까지는 시간이 필요할 것이라고 생각된다. 대신에 국내에서는 전자결재 시스템이 많이 사용되고 있다. 한편, workflow system은 비즈니스 process의 정의가 build time에 이루어지고 run time에는 그 정의에 따라 수행되는 방법이 일반적인데, 이런 방식이 주는 단점은 초기 build time에 process에 대한 이해가 부족한 상태에서 process가 정확하게 정의되기 어렵다는 점과, process의 유연성이 부족하다는 점, know-how를 잃어버리기 쉽다는 점 등이다. 따라서, 본 논문에서는 incremental approval방식이 유리하다고 주장한다. 한국의 기업환경과 실정의 고려해 볼 때 더욱 그렇다고 주장한다. 또, 전자결재 시스템과 workflow system의 유사점과 차이점을 분석하고 현재의 전자결재 시스템을 이용하면, workflow system의 incremental approval을 위한 prototype이 개발될 수 있다고 주장한다.

• Restorative Dentistry and Endodontics
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• 제29권2호
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• pp.191-199
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• 2004

The purposes of this study were to estimate the material properties of the recently developed domestic composite resins for core filling material (Chemical, Dual A, Dual B；Vericom, Korea) and to compare them with other marketed foreign products (CorePaste, Den-Mat, USA；Ti-Core, Essential Dental Systems, USA；Support. SCI-Pharm. USA). Six assessments were made：working time. setting time. depth of polymerization. flexural strength. bonding strength. and marginal leakage. All items were compared to ISO standards. All domestic products satisfied the minimum requirements from ISO standards (working time：above 90 seconds. setting time：within 5 minutes). and showed significantly higher flexural strength than Core Paste. Dual A and B could. especially. reduce the setting time to 60 seconds when cured with $600mW/cm^2$ light intensity. All experimental materials showed 6 mm depth of polymerization. Bond strengths of Ti-Core and Dual B materials were significantly higher than the other materials. Furthermore. three domestic products and Ti-Core could reduce the microleakage effectively.