• Information Systems Review
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• v.12 no.3
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• pp.1-17
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• 2010

IT Systems based on Global Single Instance (GSI) can manage a corporation's internal information, resources and assets effectively and raise business efficiency through consolidation of their business process and productivity. But, It has also dangerous factor that IT system fault failure can cause a state of paralysis of a business itself, followed by huge loss of money. Many of studies have been conducted about fault-tolerance based on using redundant component. The concept of fault tolerance is rather simple but, designing and adopting fault-tolerance system is not easy due to uncertainty of a type and frequency of faults. So, Operational fault management that working after developed IT system is important more and more along with technical fault management. This study proposes the fault management process that including a pre-estimation method using TRM (Technical Reference Model) check point and event rule engine. And also proposes a effect of fault-free process through built fault management system to representative company of Hi-tech industry. After adopting fault-free process, a number of failure decreased by 46%, a failure time decreased by 56% and the Opportunity loss costs decreased by 77%.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.3
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• pp.281-287
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• 2011

We consider the uncertainty in the elastic buckling formula for a thin tube. We take into account the measurement uncertainty of Young's modulus and Poisson's ratio and the tolerance of the tube thickness and diameter. Elastic buckling must be prohibited for a thin tube such as a nuclear fuel rod that must satisfy a self-stand criterion. Since the predicted critical buckling pressure overestimated that found in the experiment, the determination of the minimum safety factor is crucial. The uncertainty in each parameter (i.e., Young's modulus, Poisson's ratio, thickness, and diameter) is mutually independent, so the safety factor is evaluated as the sum of the inverse of each uncertainty. We found that the thickness variation greatly affects the uncertainty. The minimum safety factor of a thin tube of Zirconium alloy is evaluated as 1.547 for a thickness of 0.87 mm and 3.487 for a thickness of 0.254 mm.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.1
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• pp.1-9
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• 1980

In this paper several basic techniques for signal processing and analysis are surveyed. Firstly by the intervention of the uncertainty principle, an equality sign may have different degree of precision if non commutable operators are applied. Seconds y maximum entropy estimate and randam process based viewpoint must be enhanced to get rid of the well established and reigning deterministic image of science. Thirdly techniques for the analysis of a signal namely detection. ess]motion and modulation are explained as well as the positive definiteness of a covariance function, Karhunen-Loeve expansion and SVD of an image.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.1
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• pp.1-12
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• 2010

Recently, large amount of information in IDS(Intrusion Detection System) can be un manageable and also be mixed with false prediction error. In this paper, we propose a data mining methodology for IDS, which contains uncertainty based on training process and post-processing analysis additionally. Our system is trained to classify the existing attack for misuse detection, to detect the new attack pattern for anomaly detection, and to define border patter between attack and normal pattern. In experimental results show that our approach improve the performance against existing attacks and new attacks,from 0.62 to 0.84 about 35%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.672-675
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• 1995

Because of a sudden growth of the research of fatigue failure, recent machines or structures have been designed by damage tolerance design in many fields. Consequently, it is the most primary factor to clarity the specific character of fatique failure in the design of machines or structures considering reliability. A statistical analysis is required to analyze the outcome of an experiment or a life estimate by reason of that fatigue failure contains lots of random elements. Reliability analysis which has tukenn the place of the existing analyses in the consideration of the uncertainty of a material, is a very efficient way. Even reliability analysis, however, is not a perfect way to analyses the uncertainties of all the materials. This thesis would refer to a newly conceived data analysis that the coefficient of a system could cause the ambiguity of the relationship of an input and output.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2257-2264
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• 1994

A method to evaluate the position performance for a stochastically defined planar robot manipulator is presented. Performance is defined as the operational reliability based upon the positional errors of the manipulator tip. An analytical method is developed and applied to a two-link robot manipulator through forward kinematics. This study includes uncertainties in the link length, pin center location and radial clearance. By virtue of the effective link length model, only the nominal manipulator model and statistical information on the uncertainties are required. The results from the analytical method is compared to those from the Monte Carlo simulation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.1
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• pp.102-111
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• 2017

An automobile ball joint is the element for connecting the control arm and the knuckle arm, allowing rotational motion. The ball joint consists of the stud, plug, socket, and seat. These components are assembled through the caulking process that consists of plugging and spinning. In the existing research, the pull-out strength and gap stiffness were calculated, but we did not consider the uncertainties due to the numerical analysis and production. In this study, the uncertainties of material property and tolerance are considered to predict the distributions of pull-out strength and gap stiffness. Also, pull-out strength and gap stiffness are predicted as the a distribution rather than one deterministic value. Furthermore, a robust design applying the Taguchi method is suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.89-89
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• 2004

결정적인 알고리즘과 입력정보의 사용은 평가된 해석과 실제 시스템 값과의 차이로 잘못된 결론을 이끌지도 모른다. 실제 시스템은 대부분 각각의 입력 매개변수들(input parameters)과 관계된 넓은 공차 영역(tolerance band)을 가지고 있어서 입력정보로 하나의 단일한 값을 할당하는 것이 어렵다. 단일 입력에 대한 한가지 해는 변동의 이해 없이 제한된 값이라는 것을 인식할 필요가 있는데 대개 결정론적 설계는 형상과 관련된 치수변동, 항복강도나 부재의 밀도, 탄성계수와 같은 재료 물성치의 불확실성(uncertainty)과 시스템에 작용하는 하중의 변동 등을 직접 고려하지 않고 설계를 수행하기 때문에 수용할 수 있는 오차의 범위 안에서 시스템의 응답을 정확히 평가하기가 쉽지 않았다.(중략)

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.199-207
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• 2010

Recently, large amount of information in IDS(Intrusion Detection System) can be un manageable and also be mixed with false prediction error. In this paper, we propose a data mining methodology for IDS, which contains uncertainty based on training process and post-processing analysis additionally. Our system is trained to classify the existing attack for misuse detection, to detect the new attack pattern for anomaly detection, and to define border patter between attack and normal pattern. In experimental results show that our approach improve the performance against existing attacks and new attacks, from 0.62 to 0.84 about 35%.

• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.509-522
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• 2011

FRAPCON-3.4a and FRAPTRAN 1.4 are the most recent versions of the U.S. Nuclear Regulatory Commission (NRC) steady-state and transient fuel performance codes, respectively. These codes have been assessed against separate effects data and integral assessment data and have been determined to provide a best estimate calculation of fuel performance. Recent updates included in FRAPCON-3.4a include updated material properties models, models for new fuel and cladding types, cladding finite element analysis capability, and capability to perform uncertainty analyses and calculate upper tolerance limits for important outputs. Recent updates included in FRAPTRAN 1.4 include: material properties models that are consistent with FRAPCON-3.4a, cladding failure models that are applicable for loss-of coolant-accident and reactivity initiated accident modeling, and updated heat transfer models. This paper briefly describes these code updates and data assessments, highlighting the particularly important improvements and data assessments. This paper also discusses areas of improvements that will be addressed in upcoming code versions.