• Journal of Environmental Science International
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• v.12 no.4
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• pp.367-373
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• 2003

The focus of this study was to identify and describe environmental preconceptions held by pre-service elementary teachers about three issues : greenhouse effect, ozone layer depletion and acid rain. Two hundred and twenty nine pre-service elementary teachers participated in this study. A 36 question survey was created by one of the authors. The questions focused on the cause, effects, and interactions of three environmental issues greenhouse effect of one layer depletion and acid rain. Pre-service elementary teachers answered the questions on a Likert scale. An analysis of the survey data indicated that the majority of pre-service elementary teachers possess an array of incorrect conceptions about the causes and effects of the greenhouse effect ozone layer depletion, and acid rain. and also many pre-service elementary teachers thought that there were causal relationships among the increase in greenhouse effect, the destruction of ozone layer, and the increase of acid rain.

• Journal of Astronomy and Space Sciences
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• v.16 no.2
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• pp.159-166
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• 1999

As the spatial resolution of remote sensing satellites becomes higher, very accurate determination of the position of a LEO (Low Earth Orbit) satellite is demanding more than ever. Non-symmetric Earth gravity is the major perturbation force to LEO satellites. Since the orbit propagation is performed in the celestial frame while Earth gravity is defined in the terrestrial frame, it is required to convert the coordinates of the satellite from one to the other accurately. Unless the coordinate conversion between the two frames is performed accurately the orbit propagation calculates incorrect Earth gravitational force at a specific time instant, and hence, causes errors in orbit prediction. The coordinate conversion between the two frames involves precession, nutation, Earth rotation and polar motion. Among these factors, unpredictability and uncertainty of Earth rotation, called UTI-UTC, is the largest error source. In this paper, the effect of UTI-UTC on the accuracy of the LEO propagation is introduced, tested and analzed. Considering the maximum unpredictability of UTI-UTC, 0.9 seconds, the meaningful order of non-spherical Earth harmonic functions is derived.

• Korean Journal of Cognitive Science
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• v.10 no.1
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• pp.13-24
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• 1999

In this paper, we propose a classifier based on modular networks using an unsupervised learning method. The structure of each module is designed through stochastic analysis of input data and each module classifier data independently. The result of independent classification of each module and a measure of the nearest distance are integrated during the final data classification phase to allow more precise c classification. Computation time is decreased by deleting modules that have been classified to be incorrect during the final classification phase. Using this method. a neural network sharing the best performance was implemented without considering. lots of of variables which can affect the performance of the neural network.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.6
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• pp.333-341
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• 2003

In induction motor control systems driven by the indirect vector control scheme, the rotor speed is measured to determine the flux angle which is a key variable in the control algorithm. The most popular way to measure the angular velocity is the use of rotary encoder. Since the errorneous measurement of rotor speed results in incorrect flux angle estimate, the control input generated based on the faulty information should be far from the desired (correct) value and deteriorates the overall control performance. In this paper the effects of encoder fault on motor variables and control performance are analyzed by both theoretical approach and experimental study. A parity equation based on the Power is suggested and applied to detect the incipient fault of encoder.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.29-32
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• 2000

This paper presents the analysis of Cheju power system characteristics by performing modeling/simulation in order to match the field recorded data. The comparisons between simulation results and recorded data does not show good match due to the incorrect supposed data, but it is believed that this study is enough to simulate the Cheiu power system characteristics.

• The Journal of Fisheries Business Administration
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• v.32 no.2
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• pp.127-148
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• 2001

Korean distant water trawl fisheries were sector of most important distant water fisheries with tuna long liner fisheries during the development age in Korea. Nevertheless Korean distant water trawl fisheries have suffered from catches and Income problem. It was caused to the strengthen regulation of costal countries, the rapid liberalization trend of trade on the fishing products and the shortage of cheap manpower, etc. In this situation, Korean government is inclined to convert big adjacent trawl fisheries of distant water trawl fisheries for structure adjustment In domestic fisheries. that is analyzed to incorrect method because the efficiency of management indicator in adjacent trawl fisheries was bad than distant water trawl fisheries. Then this policy of Korean government needs to convert anything else. Also it was compared with one of Japan to the efficiency of management indicator of Korean distant trawl fisheries. The result of analysis, Korea was better than Japan in some factor, especially labor cost Then if Korean government will put weighted policy on this viewpoint, Korean distant water trawl can more grow.

• Journal of The Association for Neo Medicine
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• v.1 no.1
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• pp.91-101
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• 1996

This study was subjectived elementary school books published between 1989 and 1991. There focused on the oriental medicine of all Health-Medical contents. The results of analysis for elementary school books were much less oriental medicine contents than the others.Also,it was negative trend in many contents like incorrect of historical incidence etc.That contents was not two medicine's complementarity but two division. This result did possible contribute to misunderstand and negative action toward oriental medicine in the elder age attitude. Oriental Medicine has been successive to the present and shall be continue to the future as natural korea culture. In order to continuity of normal Health-Medical culture and obtain of worldwide oriental medicine trend, it need to revise contents of elementary school books rapidly.

• Journal of Korea Multimedia Society
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• v.6 no.5
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• pp.921-927
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• 2003

There are problems to research the aquatic ecosystems. One is that an observer must be stationed in the specified environment and the other is that his subjective analysis causes incorrect results. In this paper, we proposed the model to evaluate and manage resources. It is based on the simulation of data acquisition and hydrodynamic model in the aquatic ecosystems. We used the artificial neural network to detect the collision between fluids. In the experiment result, the proposed model if very effective and accurate in the detection of collision.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.623-627
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• 2009

Recently, we have many kinds of picture format and display, and resizing (scaling) of picture becomes important. In this processing, quality of picture depends on re-sizing method. For this, some methods to improve the PSNR have been proposed. However, subjective picture quality is more important. Especially, degradation caused by re-sizing, such as jaggy (aliasing) and ringing, should be reduced. To solve them, we have proposed the method using directional adaptive interpolation. To improve the performance of this method, we consider the shape analysis this time. In the proposed method, directional adaptive processing is applied for pure edge only. In the texture area and flat area, 8 tap re-sampling filter is used. As the results of processing, the reductions of jaggy and incorrect interpolated pixels are recognized. The subjective picture quality of proposed method is significantly better than 8-tap re-sampling which gives good PSNR.

• Journal of Drive and Control
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• v.9 no.2
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• pp.28-38
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• 2012

Monitoring of system cleanliness levels and counting of particulate contaminant are fundamental to achieving hydraulic system reliability as any departure from the specified cleanliness level is often a precursor to future failures. On-line monitoring of cleanliness levels has the advantage of giving data both very quickly and accurately as environmental influences are eliminated. In this way, corrective actions can be promptly implemented. Most on-line instruments are sensitive to system conditions to a greater or lesser extent, but Automatic Particle Counters (APCs) working on light extinction principles are especially sensitive to the presence of optical interfaces caused by such conditions as fluid mixtures, emulsions, free water and air bubbles. These conditions give erroneous data and can result in drawing incorrect conclusions, wasting maintenance time and ultimately, reduced user confidence in cleanliness monitoring. This paper describes such conditions and shows how the correct selection of the analysis technique can result in reliable cleanliness level data.