• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2545-2547
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• 2000

In this paper, a hybrid fuzzy controller using genetic algorithm based on parameter estimation mode to obtain optimal control parameter is presented. First, The control input for the system in the HFC is a convex combination of the FLC's output in transient state and PID's output in steady state by a fuzzy variable, namely, membership function of weighting coefficient. Second, genetic algorithms is presented to automatically improve the performance of hybrid fuzzy controller utilizing the conventional methods for finding PID parameters and estimation mode of scaling factor. The algorithms estimates automatically the optimal values of scaling factors, PID parameters and membership function parameters of fuzzy control rules according to the rate of change and limitation condition of control input. Computer simulations are conducted to evaluate the performance of proposed hybrid fuzzy controller. ITAE, overshoot and rising time are used as a performance index of controller.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.18-21
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• 1996

This research is the basical experiment for designing kVp meter using the photo-conductive property of Amorphous Selenium. At first, we charged the surface with A re discharge method, and changed the formed surface potential voltage by x-raying on that surface. As a result the variations of the surface charge increased by the rising kVp, while maintaining a constant exposure time and mA. We become to know that we can apply the photoconductive property of Amorphous Selenium in designing kVp meter.

• Korean Journal of Weed Science
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• v.17 no.1
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• pp.112-123
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• 1997

Chemical pesticides have been re used for a long time to protect crops from diseases, insects, and weeds ; ample and secure supply of foods in present days would not be possible without them. However, concerns on the risk of using chemical pesticides rising steadily in recent years forced discard many of them and seek an alternate, environment-friendly control strategies. Microbial pesticide is regarded as one of the most promising methods because if properly developed, it will be effective, cheap, and environment-safe. Currently, about 180 microbial pesticides are under development throughout the world and at least 20 of them including B.t. and antibiotics are registered in Korea. This paper discusses some of the successful examples, intriguing problems, and future prospects of microbial pesticides.

• Steel and Composite Structures
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• v.19 no.6
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• pp.1421-1447
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• 2015

In this paper, the effect of material-temperature dependent on the wave propagation of a cantilever beam composed of functionally graded material (FGM) under the effect of an impact force is investigated. The beam is excited by a transverse triangular force impulse modulated by a harmonic motion. Material properties of the beam are temperature-dependent and change in the thickness direction. The Kelvin-Voigt model for the material of the beam is used. The considered problem is investigated within the Euler-Bernoulli beam theory by using energy based finite element method. The system of equations of motion is derived by using Lagrange's equations. The obtained system of linear differential equations is reduced to a linear algebraic equation system and solved in the time domain and frequency domain by using Newmark average acceleration method. In order to establish the accuracy of the present formulation and results, the comparison study is performed with the published results available in the literature. Good agreement is observed. In the study, the effects of material distributions and temperature rising on the wave propagation of the FGM beam are investigated in detail.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.328-331
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• 2009

This paper presents the behaviors of transient and conventional grounding impedances of a 30m counterpoise according to the injection point of lightning impulse currents. As a result, the trend of the conventional grounding impedances measured as a function of risetime of impulse current is similar to the transient grounding impedance of counterpoise. The injection point of impulse current greatly influences on the transient grounding impedance characteristics of counterpoise. The transient grounding impedances strongly depend on the injection point and the rising time of impulse current and the soil characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.481-484
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• 2004

A form of measured temperature distribution to estimate condition of a electrical apparatus is a absolute reference for condition of the apparatus, time rate of transition, and difference between reference and currently temperature. Because passive thermography which has not injection of external thermal stimulation shows difference of temperature being on surface of a structure and temperature difference between the structure and back ground, the result could apply only to estimation or monitor for condition of terminal relaxation and overload related with temperature rising. However, a thermal flow in active thermography is differently generated by structure and condition of surface and subsurface. This paper presents the nondestructive testing using the properties and includes the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.

• Smart Structures and Systems
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• v.22 no.6
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• pp.699-709
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• 2018

With increasing traffic volumes and rising vehicle traffic, especially in cities, the number of pedestrian bridges has also increased significantly. Like all other structures, pedestrian bridges also suffer damage. In order to increase the safety of pedestrians, it is necessary to identify existing damage and to repair them to ensure the safety of the bridge structures. Owing to the shortcomings of local methods in identifying damage and in order to enhance the reliability of detection and identification of structural faults, signal methods have seen significant development in recent years. In this research, a new methodology, based on cone-shaped kernel distribution with a new damage index, has been used for damage detection in pedestrian truss bridges. To evaluate the proposed method, the numerical models of the Warren Type steel truss and the Arregar steel footbridge were used. Based on the results, the proposed method and damage index identified the damage and determined its location with a high degree of precision. Given the ease of use, the proposed method can be used to identify faults in pedestrian bridges.

• Korean Journal of Artificial Intelligence
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• v.7 no.1
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• pp.13-16
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• 2019

While the Chinese banks have started the impact of foreign banks. At the same time, rising pressure on foreign exchange reserves and appreciation of the renminbi has prompted Chinese banks to go abroad and diversify their risks. The financial crisis of 2008 has caused the continued turbulence of the major financial markets around the world, and the valuation of foreign financial institutions has been drastically shrinking, providing opportunities for Chinese banks to carry out overseas M&A. Based on the overseas M&A status of Chinese commercial banks, this paper sums up the characteristics of the overseas M&A. Then taking a series of overseas M&A conducted by ICBC from 2006 to 2011 as an example, it analyzes the relationship between M&A and performance growth using grey incidence model. The test shows: there is a positive correlation between both overseas M&A and interest rate differential with performance growth of ICBC, and overseas M&A transactions role in promoting the performance growth is significantly higher than the interest rate differential.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2381-2389
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• 1993

In this paper the design and test results of a dynamic flow rate sensor was reported. This sensor comprises an 2-way cartridge valve as standard hydraulic component and a displacement sensor. Its working principle bases on the linear relationship between the flow rate and the piston displacement of 2-way cartridge valves under constant pressure drop. This principle is well known, however it is not easy to develop a flow rate sensor with the measurement range of 300 1/min, pressure loss of less than 8 bar at 300 1/min, maximum linearity error of less than $\pm$1% and the maximum rising time of 10 ms. This paper describes the design procedure of the flow rate sensor, the improvement procedure of static performance and test method and results of dynamic performance.

• Korean Institute of Interior Design Journal
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• no.34
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• pp.86-95
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• 2002

In the 1950’s, after modernistic hospital is begun to build in our country, there were much changes in hospital construction plan such as function, scale, operation, technology for 40 years so far. Interest about 'Healing environment furtherance' which is one of basic function of hospital within these change is continued. Specially, concept about furtherance of healing environment limited in ward department in the early time is applied to hospital space magnificently whole coming at present. Entrance of hospital and change of Lobby may speak as the representative example. This interest about practically use of lobby is rising gradually. Lobby adds to existed concept of space to the importance revaluated. The first purpose of this study is to investigates main entrance and lobby of representative hospital in our country and to search change and present condition. The second purpose is hereupon to present necessary objective standard with direction of lobby plan in general hospital forward though this.