• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.825-833
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• 2020

Currently, the K-Water uses various valves that can be remotely controlled for optimal water management. Valve system fault can be classified into rotor defects, stator defects, bearing defects, and gear defects of induction motors. If the valve cannot be operated due to a gear fault, the water management operation can be greatly affected. For effective water management, there is an urgent need for preemptive repairs to determine whether gear is damaged through failure prediction diagnosis.. Recently, deep learning algorithms are being applied for valve failure diagnosis. However, the method currently applied has a disadvantage of attaching a vibration sensor to the valve. In this paper, propose a new algorithm to determine whether a fault exists using a convolutional neural network (CNN) based on the voltage and current information of the valve without additional sensor mounting. In particular, a normalized Lisasjous diagram was used to maximize the fault classification performance in the CNN-based diagnostic system.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.61-68
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• 1991

The system such as railway bridge can be modelled as the restrained beam with intermediate supports. This kind of structures are subject to the moving load, which has a great effect on dynamic stresses and can cause sever motions, especially at high velocities. Therefore, to analyze the dynamic characteristics of the system due to the moving load is very important. In this paper, the governing equation of motion of a restrained beam subjected to the moving load is derived by using the Hamilton's principle. The orthogonal polynomial functions, which are trial functions and satisfying the geometric and dynamic boundary conditions, are obtained through simple procedure. The dynamic response of the system subjected to the moving loads is obtained by using the Galerkin's method and the numerical time integration technique. The numerical tests for various constraint, velocity and boundary conditions were preformed. Furthermore, the effects of mass of the moving load are studied in detail.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.4
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• pp.165-172
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• 2006

In this paper we present a technique for detecting cross-reference points that allows improving watermark detect-ability. In general, Harris detector is commonly used for finding salient points. Harris detector is a kind of combined corner and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. The new method proposed in this paper used not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we constructed pre-specified number of virtual lines from top to bottom and left to right, and several of cross points were selected by a random key. These selected points specify almost same positions with the accuracy more than that of Harris detector after digital attacks. These points were arranged by a random key, and blocks centered in these points were formed. A reference watermark is formed by a block and embedded in the next block. Because same alteration is applied to the watermark generated and embedded blocks. the detect-ability of watermark is improved even after digital attacks.

• Journal of the Korean housing association
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• v.16 no.1
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• pp.17-25
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• 2005

Recently there has been increasing the population of the elderly, the welfare of the elderly is no longer family's and personal problems. It is a social issue that the communities have a role to supply the systematic welfare service of the elderly and the facilities. Therefore It is needed to study the extended function and role of Gyungrodang because Gyungrodang is the most wide spreaded welfare service facilities for the normal elderly in urban single housing district. The subject of this study is to propose the facilities' program improvement method for the Gyungrodang that hold a extended role as a community welfare service facility for the elderly. This paper Is assessed as an sustainable research of normalization of the old people's living. By the comparison analysis of the existing Gyungrodang in Daejeon City and the investigation results of the welfare service present condition of the elderly in Daejeon City, finally the facilities' program improvement direction for the Gyungrodang is proposed.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.3
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• pp.293-298
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• 2015

The vessel encounter data collected from the vessel trajectories in the maritime traffic situation is possible to analyze vessel collision and near-collision risk using statistical method. In this study, analyzing variables extracted from the vessel encounter data using factor analysis, we determine main factors effecting vessel collision risk from vessel encounter data. In order to calculate each factor, it used principal component analysis for factor analysis after normalization and standardization of vessel encounter variables. As a result of the factor analysis, main effect factors are summarized into the vessel approach factor and collision avoidance variance factor.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.579-586
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• 2002

With increase of servo motor in industrial and home application, a number of papers related to PMSM control have been researched. Among them, sensorless control schemes are especially concerned in a view point of their cost reduction. In a conventional approach, a rotor position is generally estimated by the integration of estimated rotor speed. In this method, because of their tight relationship between the amplitude of back-emf and rotor position, it is somewhat difficult to find two parameters at the same time. To solve this problem, a novel sensorless control scheme is proposed. It utilizes a back-emf normalization, so that it does not require the variables related with the amplitude of back-emf. The validity of the proposed control scheme is verified through experimental results.

• Journal of Biosystems Engineering
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• v.33 no.5
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• pp.309-316
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• 2008

The goal of this study was to develop prediction models to estimate the storage days of tomato. The transmittance spectral data measured on tomato were preprocessed through normalization, SNV, Savitzky-Golay, and Norris Gap and then were used to build the prediction models using partial least square (PLS) method. For the experiments, the tomato samples of different varieties were collected at different harvest time. The samples were taken right after harvest from the field and then were stored in a low-temperature storage room in which room temperature was maintained at $10^{\circ}C$. The transmittance spectral data of the tomato samples were measured at three-day intervals for 16 days. The performance of the prediction models was affected by the preprocessing techniques as well as the varieties and harvest time of the tomato. The best model was found when SNV was applied. The accuracy of the best model was 90.2%. It can be concluded that the transmittance spectra are useful information for predicting the period of storage of tomato.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.3
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• pp.117-131
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• 2014

As interests in the management of government-owned corporation rise, in these days, debt reduction and normalization of management of those companies have been proceeding under the lead of government. At this point, it is very important to seek internal marketing method for improvement of internal employees' satisfaction, loyalty and organization performance. This study analyzes impact of factors of internal marketing effect on organization satisfaction, loyalty and organization performance in the context of the domestic public companies, the Korea Electric Power Corporation (KEPCO) and the Korea Water Resources Corporation (K-WATER)'s employees empirically. There are some significant differences between the two publics. It is proved that delegation of the authority influences on internal satisfaction and organization performance in the case of KEPCO, and education and training influence on internal satisfaction and organization performance in the case of K-WATER. On the other hand, in the case of K-WATER, any internal marketing factors don't influence on loyalty. The results of this study show somewhat different characteristics depending on the characteristics of firm, however, it is expected that this study can be very useful in regards to similar public enterprises or businesses.

• Journal of the Korea Computer Industry Society
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• v.8 no.4
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• pp.281-288
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• 2007

In this paper, we set 6 interesting points around lips. Analyzed and characterized is the distance change of these 6 interesting points when people pronounces 5 vowels of Korean language. 450 data are gathered and analyzed. Based on this analysis, the system is constructed and the recognition experiments are performed. In this system, we used the camera connected to computer to measure the distance vector between 6 interesting points. In the experiment, 80 normal persons were sampled. The observational error between samples was corrected using normalization method. We analyzed with 30 persons and experimented with 50 persons. We constructed three recognition systems and of those the neural net system gave the best recognition result of 87.44 %.

• Proceedings of the KSRS Conference
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• v.2
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• pp.852-855
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• 2006

There is an increasing need to use data from different sensors in order to maximize the chances of obtaining a cloud-free image and to meet timely requirements for information. However, the use of data from multiple sensor systems is depending on comprehensive relationships between sensors of different types. Indeed, a study of inter-sensor relationships is well advanced in the effective use of remotely sensed data from multiple sensors. This paper was concerned with relationships between sensors of different types for vegetation indices (VI). The study was conducted using IKONOS and Landsat-7 ETM+ images. IKONOS and Landsat-7 ETM+ image of the same or about the same dates were acquired. The Landsat-7 ETM+ images were resampled in order to make them coincide with the pixel sizes of IKONOS. Inter-relationships of vegetation indices between images were performed using at-satellite reflectance obtained by converting image digital number (DN). All images were applied to topographic normalization method in order to reduce topographic effect in digital imagery. Also, Inter-sensor model equations between two sensors were developed and applied to other study region. In the result, the relational equations can be used to compute or interpret VI of one sensor using the VI of another sensor.