• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.2
• /
• pp.135-141
• /
• 2004

We developed a polarimetric fiber-optic current sensor system for protective relaying usage. A fiber sensing coil that consisted of a length of twisted fiber and a FRM (Faraday rotator mirror) was used in order to suppress the linear birefringence effect. From the experiments with various sensing coil configurations and environmental conditions, the proposed current sensor system showed feasibility of suppressing environmental noises, and the obtained measurement stability was less than $\pm$3％ at rated primary current.

• Journal of the Korean Society of Systems Engineering
• /
• v.12 no.2
• /
• pp.39-45
• /
• 2016

In order to successfully develop a large complex system, it is important that the systems engineering processes take into account the program context and characteristics. Among these processes, the requirements management process requires a management plan based on the program plans and systems engineering management plan (SEMP) to the connection with the program management system and the policy directives. In this paper, a systems engineering based requirement management scheme and guidelines for writing requirements are proposed. is proposed.

• Journal of the Korean Society of Systems Engineering
• /
• v.11 no.2
• /
• pp.115-124
• /
• 2015

The major challenge of designing public halls or performing arts centers in Japan is meeting the expectations of the regional community; greater stakeholder involvement is required in order to solve this problem. The purpose of this paper is to examine whether stakeholders can become more involved in public hall design by using systems engineering (SE), which has never before been applied when designing public halls. As such, this study redesigned an actual public hall (Iwaki Alios) using an SE approach. The results revealed that applying SE was effective in the creation of a public hall concept.

• Convergence Security Journal
• /
• v.2 no.2
• /
• pp.165-177
• /
• 2002

IDS(Intrusion Detection System) evasion is a technology which uses vulnerability of IDS in order not to be detected by IDS. In this paper, at first, we classify IDS evasion technology. Second, we propose detection model of IDS evasion technology. Finally, we design and implement detection system of IDS evasion.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.100-101
• /
• 2014

The global warming because of the CO₂ emission and solution about this emerge as the international enviroment problem. Particularly, it is the absolutely it is needed for reducing the CO₂ in the cement industry and harmful material actual condition. And the construction of home and abroad and material manufacturers tries for the technology development for the carbon dioxide and harmful material reduction which the portland cement in manufacture is usually emitted along with the increase of concerns about the environment-friendly concrete and panel. Therefore, in this research, the compressive strength of the inorganic binder and flexural strength tries to be measured in order to draw the inappropriate high temperature cure time of the ternary system inorganic binder using the blast furnace slag, red mud, silica fumewhich is the industrial byproduct with the cement substitute material, and etc.

• Journal of the Korean Institute of Navigation
• /
• v.25 no.4
• /
• pp.371-379
• /
• 2001

We have reported the new measurement system which was substituted digital filter for the analog filter in order to develop the optimal system that could find the time delay between each sensors with high accuracy. And also we have confirmed through the experiments that the accuracy of measurements were differentiated by the methods what kind of digital filter had been adopted. This paper suggests two algorithms which approximate the sound source's bearing and distance. One is that sound source's relative bearing can be approximately regarded as the gradient of hyperbolic asymptote, the other is that the source's range can be approximated under the condition of a long range source relative to the sensor's interval. And a series of experiments were carried out with the source's distance 22.42meters and the random bearing interval within the limits of $-90^{\circ}$~$+90^{\circ}$. As a result, we have recognized that the approximation methods could measure the bearing and distance with higher accuracy than the method using trigonometric relation could do.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.2
• /
• pp.309-314
• /
• 2009

PC users could experience some inconvenience when they use their PC that was physically connected to network printers shared by other People in the network due to the overload. This paper shows how to resolve this kind of overload problem and established the embedded printer system based on embedded Linux system which performs the printer server in order for any users in the of ice to do printing work more smoothly via current network. It's own capabilities and functions were verified throughout the various tests in practical environment.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.2 no.1
• /
• pp.38-42
• /
• 2002

A fast iterative solving method of fuzzy relational equation is proposed. It is derived by eliminating a redundant comparison process in the conventional iterative solving method (Pedrycz, 1983). The proposed method is applied to image reconstruction, and confirmed that the computation time is decreased to 1 / 40 with the compression rate of 0.0625. Furthermore, in order to make any initial solution converge on a reconstructed image with a good quality, a new cost function is proposed. Under the condition that the compression rate is 0.0625, it is confirmed that the root mean square error of the proposed method decreases to 27.34% and 86.27% compared with those of the conventional iterative method and a non iterative image reconstruction method, respectively.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.14 no.2
• /
• pp.331-338
• /
• 1990

In adaptive control, the lack of persistent and rich excitation causes the estimated parameters to drift, which degrade the performance of the system and may introduces instability to the system in a stochastic environment. To solve the problem of the parameter drift, the concept of single parameter adaptation is presented. For the parameter identification, a priori error is directly used for adaptation error. The structure of the controller is based upon the minimum variance control technique. The stability and robustness analysis is carried out by the sector stability theorem for the second order system. The computer simulation is performed to justify the theoretical analysis for the various cases.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.20 no.2
• /
• pp.122-128
• /
• 2010

This paper presents vibration control performance of active engine mount system installed with the magneto-rheological(MR) mount and the piezostack mount. The performance is evaluated via hardware-in-the-loop-simulation(HILS) method. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three point mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. As a second step, sliding mode controller(SMC) is synthesized to actively control the imposed vibration. In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds(wide frequency range) using HILS method and presented in time and frequency domain.