• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권2호
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• pp.201-206
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• 2010

발전소와 임베디드 시스템, 지능형 빌딩과 같은 현대의 대부분의 시스템은 PLC 라는 특수목적 컴퓨터를 이용하여 자동제어된다. PLC 프로그래밍 언어 중에서 가장 많이 사용하는 것은 LD 프로그램이다. LD 프로그램의 검증은 시뮬레이션과 테스팅등을 통해 이루어지는데 이러한 방법은 프로그램 검증에 한계가 있다. 본 논문에는 LD 프로그램의 검증시 모델 체킹을 사용할 수 있도록 주어진 LD 프로그램을 모델 체커의 입력으로 자동으로 변환하는 방법을 기술한다. LD 프로그램과 SMV 모델의 의미구조를 정의 하고 이를 바탕으로 의미가 보존되는 변환 함수를 정형적으로 나타낸다.

• 대한치과기공학회지
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• 제36권2호
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• pp.83-89
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• 2014

Purpose: This study is to evaluate the effect of modeling liquid on the shear-bond strength between zirconia core and veneering ceramic. Methods: Disk-shaped (diameter: 12.0mm; height: 3.0mm) zirconia were randomly divided into six groups according to the surface conditioning method and whether modeling liquid is used or not to be applied (N=60, n=10 per group): group 1-control group with distilled water(ZD); group 2-control group with modeling liquid(ZM); group 3-airborne particle abrasion with $110-{\mu}m$ $Al_2O_3$(AD) with distilled water; group 4-airborne particle abrasion with $110-{\mu}m$ $Al_2O_3$ with modeling liquid(AM); group 5-liner with distilled water(LD); group $6{\pounds}{\neq}liner$ with modeling liquid(LM). Contact angles were determined by the sessile drop method at room temperature using a contact angle measurement apparatus. The specimens were prepared using dentin veneering ceramics, veneered, 3mm high and 2.8mm in diameter, over the cores. The shear bond strength test was performed in a Shear bond test machine. Load was applied at a cross-head speed of 0.50mm/min until failure. The fractured zirconia surfaces were evaluated by using stereomicroscope (${\times}30$). Collected data were analyzed using SPSS(Statistical Package for Social Sciences) Win 12.0 statistics program. Results: ZD showed the highest contact angle($50.6{\pm}5.4^{\circ}$) and LD showed the lowest value($6.7{\pm}1.3^{\circ}$). Control groups and zirconia liner groups were significantly higher contact angle than liner groups(p<0.05). LD was the highest shear bond strength($43.9{\pm}3.8MPa$) and ZD was the lowest shear bond strength($24.8{\pm}4.9MPa$). Shear bond strengths of control groups and contact angle of liner groups were not significantly different((p>0.05). Liner groups presented adhesive failures. The others groups showed cohesive and adhesive failures. Conclusion: Modeling liquid groups showed lower contact angles and lower shear bond strength compared to those of distilled water groups.

• 한국CDE학회논문집
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• 제14권1호
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• pp.60-68
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• 2009

Because of the reduced product life-cycle, industries are making an effort to bring down the process planning time. In the traditional approach, we have to analyze established process planning, then design the time chart based on process information and drawing the formal time chart such as SOP(sequence of operation). Thereafter, it will be converted to PLC code that is a time consuming and redundant job. Similarly, Industrial automated process uses PLC Code to control the factory; however, control information and control code(PLC code) are difficult to understand. Hence, industries prefer writing new control code instead of using the existing one. It shows the lack of information reusability in the existing process planning. As a result, to reduce this redundancy and lack of reusability, we propose SOS-Net modeling method. Unlike past stabilized process planning that is rigid to any change; our proposed SOS-Net modeling method is more adaptable to the new changes. The SOS-Net model is easy to understand and easy to convert into PLC Code accordingly. Therefore, we can easily modify the control information and reuse it for new process planning. The proposed model plays an intermediary role between process planning and PLC code generation. It can reduce the process planning and implementation time as well as cost.