• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2011-2022
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• 2022

According to the defense-in-depth concept, not only a preventive strategy but also an integrated cyberattack response strategy for NPPs should be established. However, there are limitations in terms of responding to penetrations, and the existing EOPs are insufficient for responding to intentional disruptions. In this study, we focus on manipulative attacks on process data. Based on an analysis of the related attack vectors and possible attack scenarios, we adopt the Kalman filter to detect process anomalies that can be caused by manipulations of process data. To compensate for these manipulations and secure MCR operators' situational awareness, we modify the Kalman filter such that it can filter out the effects of the manipulations adaptively. A case study was conducted using a hardware-in-the-loop system. The results indicated that the developed method can be used to verify whether the displayed safety-related state data are reliable and to implement the required safety response actions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7357-7363
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• 2014

Korea had been known as safe region regarding volcanic disasters. On the other hand, Baekdu mountain experienced a large eruption one thousand years ago and the precursor phenomena for a volcanic eruption have been frequently reported these days. Therefore, a number of volcano experts, who warn of a volcanic eruption on the Korean peninsula, has increased. This paper describes the utilization plan and evolution of developing volcanic disaster response system based on spatial information and scientific modeling process for Baekdu mountain. First, the business processes for volcanic disaster response are derived based on an analysis of business system and related IT-based systems. Second, the design and development of a volcanic disaster response system are derived based on the business process. Third, a utilization plan is suggested to maximize the efficiency of the system. The application of the suggested volcanic disaster response system to NEMA, additional tests and system supplementation should be carried out. The complete volcanic disaster response system, which will be implemented based on this research, is expected to minimize the volcanic disaster damage in the area of Korea, China and Japan.

• Journal of the Korean Operations Research and Management Science Society
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• v.26 no.4
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• pp.71-82
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• 2001

Using the computer simulation method, we invest19ate the probability distribution of maximum eigenvalue of pair-wise comparison matrix, which has been used as a parameter for measuring the consistency of responses in analytic hierarchy process (AHP). We show that the shape of the distribution of the maximum eigenvalue is different according to the dimension of the matrix. In addition, we cannot find any evidence that the distribution of the Consistency Index is a Normal distribution, which has been claimed in the Previous literature. Accordingly, we suggest using so called K-index calcu1ated based on the concept of cumulative distribution function lather than based on that of arithmetic mean because the probabilistic distribution cannot be assumed to be a Normal distribution. We interpret the simulation results by comparing them with the suggestion of Saaty[11]. Our results show that using Saaty＇s value could be too generous when the dimension of the matrix is 3 and strict over 4. Finally, we propose new criteria for measuring the response consistency in AHP.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.786-791
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• 2005

This paper is concerned with the examination and evaluation concerning a tuning method of multivariable PID controllers based on partial model matching on frequency domain proposed by authors from practical view point. In this case, PID controller parameters are determined by minimizing the loss function defined by the difference between frequency response of ideal model transfer function and actual frequency response on several frequency points. The purpose of the paper is to examine and evaluate the performance of the method through actual experiments of MIMO liquid level experimental process control equipment.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.618-620
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• 1997

A $50{\times}50{\mu}m^2$ aluminum micromirror array is fabricated using shadow evaporation process. The fabrication process is very simple with use of shadow evaporation process, and the micromirror array has a high fill-factor. The static and dynamic characteristics such as deflection angle vs. applied voltage, step response, and frequency response are measured using a contact free optical measurement technique. The downward threshold voltage was 8 V, step response time was $13.5{\mu}s$ when 32 V step voltage applied, and a resonance observed at 11kHz. The lifetime of micromirror with anti-stiction coating was tested and micromirror operated successfully over 200 million cycles of touch-down operations.

• Transactions of Materials Processing
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• v.15 no.3 s.84
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• pp.226-231
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• 2006

The fuel injector is a pa.1 that controls the fuel supply of automotive engine. The housing of the fuel injector supports the rod, the needle valve and the solenoid. In this study, the rigid-plastic FE-analysis by using the design of experiments (DOE) and the response surface methodology (RSM) has been performed to produce the product reducing the under-fill and the maximum effective strain. From the results of DOE, the stem of counter punch and the face angle of punch at the $1^{st}$ process, and the stem of punch at the $2^{nd}$ process were determined as the significant design variables far each response such as the upper under-fill, lower under-fill and the maximum effective strain. From the results of RSM, the optimal values of the design variables have been also determined by simultaneously considering the responses.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.80-84
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• 2014

The process of petroleum involves in a large amount of oily wastewater that contains high levels of chemical oxygen demand (COD) and toxic compounds. So they must be treated before their discharge into the receptor medium. In this paper, wet peroxide oxidation (WPO) was adopted to treat the oily wastewater. Central composite design, an experimental design for response surface methodology (RSM), was used to create a set of 31 experimental runs needed for optimizing of the operating conditions. Quadratic regression models with estimated coefficients were developed to describe the COD removals. The experimental results show that WPO could effectively reduce COD by 96.8% at the optimum conditions of temperature $290^{\circ}C$, $H_2O_2$ excess (HE) 0.8, the initial concentration of oily wastewater 3855 mg/L and reaction time 9 min. RSM could be effectively adopted to optimize the operating multifactors in complex WPO process.

• Transactions on Electrical and Electronic Materials
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• v.7 no.6
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• pp.297-300
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• 2006

The response surface modeling of the pretilt angle control using ion-beam (IB) alignment on nitrogen doped diamond-like carbon (NDLC) thin film layer is investigated. This modeling is used to analyze the variation of the pretilt angle under various process conditions. IB exposure angle and IB exposure time are considered as input factors. The analysis of variance technique is settled to analyze the statistical significance, and effect plots are also investigated to examine the relationships between the process parameters and the response. The model can allow us to reliably predict the pretilt angle with respect to the varying process conditions.

• Journal of the Korea Safety Management & Science
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• v.7 no.5
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• pp.233-241
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• 2005

The most important thing in the garments enterprises is fast reaction. Expecially in the China has both many population and large territory, so each region of China, for instance, northeast, northwest, huanan, huabei, has various climate and considerably different temperature. As a result China garments enterprises require different clothes at the same time. This study build a reliable market-response process as a sub module of SCM that lay emphasis on production and sale cope with specific character of China. This process build a information chain including manufacture-planning, manufacture-ordering, production, arrivals of goods, distribution, sale, sale-evaluation, cross shipment, supplement shipment, and ordering popular goods and similar products. As a result of those, the focused points of this process are real time data gathering and various analysis of data, so it can be possible supporting more faster and more accurate market decision making system and our proposed goal is accomplishment of management profit.

• Journal of the Korean Ceramic Society
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• v.47 no.5
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• pp.365-372
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• 2010

This paper was to evaluate the influence of kiln process parameter(kiln angle, kiln rotating speed) of lightweight aggregate using waste glass and bottom ash with industrial by-products on thermal conductivity, density, water absorption, fracture load and porosity by response surface analysis. In the results of surface plot and contour plot, it has verified that kiln residence time of lightweight aggregate increase as kiln angle and rotating speed decreases. For this reason, pore size and quantity tend to increase by active reaction of forming agent. It seems to be that increase in pore size and quantity have caused decreasing density, fracture load and thermal conductivity, and increasing water absorption. In conclusion, optimization of kiln process parameter on thermal conductivity, density, water absorption, fracture load and porosity by response surface analysis are kiln angle 2.4646%, kiln rotating speed 40.7089 rpm.