• Nuclear Engineering and Technology
• /
• 제31권2호
• /
• pp.157-171
• /
• 1999

In this work, an automatic software verification method for Nuclear Power Plant (NPP) protection system is developed. This method utilizes Colored Petri Net (CPN) for system modeling and Prototype Verification System (PVS) for mathematical verification. In order to help flow-through from modeling by CPN to mathematical proof by PVS, an information extractor from CPN models has been developed in this work. In order to convert the extracted information to the PVS specification language, a translator also has been developed. ML that is a higher-order functional language programs the information extractor and translator. This combined method has been applied to a protection system function of Wolsong NPP SDS2(Steam Generator Low Level Trip). As a result of this application, we could prove completeness and consistency of the requirement logically. Through this work, in short, an axiom or lemma based-analysis method for CPN models is newly suggested in order to complement CPN analysis methods and a guideline for the use of formal methods is proposed in order to apply them to NPP Software Verification and Validation.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
• /
• pp.315-320
• /
• 1998

In this work, an automatic software verification method for Nuclear Power Plant (NPP) protection system is developed. This method utilizes Colored Petri net (CPN) for modeling and Prototype Verification system (PVS) for mathematical verification. In order to help flow-through from modeling by CPN to mathematical proof by PVS, a translator has been developed in this work. The combined method has been applied to a protection system function of Wolsong NPP SDS2(Steam Generator Low Level Trip)and found to be promising for further research and applications.

• 한국수학교육학회지시리즈A:수학교육
• /
• 제44권4호
• /
• pp.535-546
• /
• 2005

We study on intuitive verification and rigor proof which are in geometry of Korean and Russian $7\~8$ grade's mathematics textbooks. We compare contents of mathematics textbooks of Korea and Russia laying stress on geometry. We extract 4 proposition explained in Korean mathematics textbooks by intuitive verification, analyze these verification method, and compare these with rigor proof in Russian mathematics textbooks.

• 대한수학회보
• /
• 제56권6호
• /
• pp.1435-1445
• /
• 2019

We consider a checkpointing model for silent errors, where a checkpoint is taken every fixed number of verifications. Assuming generally distributed i.i.d. inter-occurrence times of errors, we derive the reliability of the model as a function of the number of verifications between two checkpoints and the duration of work interval between two verifications.

• Journal of Biosystems Engineering
• /
• 제42권2호
• /
• pp.86-97
• /
• 2017

Purpose: This study aims to evaluate the applicability of a tractor-baler system equipped with a newly developed round baler by conducting stability analyses via static-state mathematical simulations and verification experiments for the tractor equipped with a loader. Methods: The centers of gravity of the tractor and baler were calculated to analyze the transverse overturning of the system. This overturning of the system was analyzed by applying mathematical equations presented in previous research and comparing the results with those obtained by the newly developed mathematical simulation. For the case of the tractor equipped with a loader, mathematical simulation results and experimental values from verification experiments were compared and verified. Results: The center of gravity of the system became lower after the baler was attached to the tractor and the angle of transverse overturning of the system steadily increased or decreased as the deflection angle increased or decreased between $0^{\circ}$ and $180^{\circ}$ on the same gradient. In the results of the simulations performed by applying mathematical equations from previous research, right transverse overturning occurred when the tilt angle was at least $19.5^{\circ}$ and the range of deflection angles was from $82^{\circ}$ to $262^{\circ}$ in counter clockwise. Additionally, left transverse overturning also occurred at tilt angles of at least $19.5^{\circ}$ and the range of deflection angles was from $259^{\circ}$ to $79^{\circ}$ in counter clockwise. Under the $0^{\circ}$ deflection angle condition, in simulations of the tractor equipped with a loader, transverse overturning occurred at $17.9^{\circ}$, which is a 2.3% change from the results of the verification experiment ($17.5^{\circ}$). The simulations applied the center of gravity and the correlations between the tilt angles, formed by individual wheel ground contact points excluding wheel radius and hinge point height, which cannot be easily measured, for the convenient use of mathematical equations. The results indicated that both left and right transverse overturning occurred at $19.5^{\circ}$. Conclusions: The transverse overturning stability evaluation of the system, conducted via mathematical equation modeling, was stable enough to replace the mathematical equations proposed by previous researchers. The verification experiments and their results indicated that the system is workable at $12^{\circ}$, which is the tolerance limit for agricultural machines on the sloped lands in South Korea, and $15^{\circ}$, which is the tolerance limit for agricultural machines on the sloped grasslands of hay in Japan.

• 호남수학학술지
• /
• 제27권4호
• /
• pp.641-647
• /
• 2005

This note is a verification on the relations between multiplicative and almost multiplicative linear maps; and the continuity of almost multiplicative linear maps.

• 대한수학회보
• /
• 제46권2호
• /
• pp.199-207
• /
• 2009

This note is a verification on the relations between almost linear and nearly additive maps; and the continuity of almost multiplicative nearly additive maps. Also we consider the stability of nearly additive and almost linear maps.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1995년도 추계학술발표회논문집(1)
• /
• pp.173-178
• /
• 1995

The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential ewer checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP (Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompleteness in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assumed error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

• Nuclear Engineering and Technology
• /
• 제28권6호
• /
• pp.522-531
• /
• 1996

The adoption of expert systems mainly as operator supporting systems is becoming increasingly popular as the control algorithms of system become more and more sophisticated and complicated. The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential error checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP(Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompletensess in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assume error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

• 한국수학교육학회지시리즈E:수학교육논문집
• /
• 제24권1호
• /
• pp.221-234
• /
• 2010

현재 알려진 피타고라스의 정리의 증명은 370여 가지가 될 정도로 다양한 증명 방법이 소개되고 있으며 이를 통해 증명 방법의 분석에 대한 많은 연구가 이루어지고 있다. 하지만 피타고라스의 정리의 일반화에 관한 연구는 부족한 실정이다. 따라서 본 연구에서는 유클리드 '원론'의 1권 명제47에 제시된 내용을 바탕으로 수학적 자료 즉, 데이터(길이, 넓이, 각의 크기 등)를 추출하여 학교수학 및 문헌 연구를 통해 피타고라스 정리의 일반화에 관한 다양한 방법을 고찰하였다.