• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.521-527
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• 1996

The Hahn double 15 hue test is used for social and vacational aptitude test to separate strongly and mildly affected subjects among the colour vision defective persons, detected using colour vision test. However, the assessment of colour vision defect type and severity is based on the hue confusions which are represented diagrammatically on Hahn double 15 hue score sheet, this qualitative assessment of the test results have not provide a numerical score suitable for methematical analysis. This paper presented a new proposal for quantitatively scoring the Hahn double 15 hue test based on those hue confusions made by the subject. With this program large numbers of double 15 hue test results can be processed easily and rapidly, and program helps to compare the severity of specific type colour vision defect and monitor acquired colour vision defect which has various disease process, continuously.

• Journal of the Korea Computer Industry Society
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• v.7 no.4
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• pp.437-446
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• 2006

Mobilecomputer offers more fundamental role than role assistance enemy of modern technology equipment and new Information <중략> These main weakness puts in structural relation between elements that compose system. Therefore, dynamics research that time urea of systematic adjustment has selected method code Tuesday nerve dynamics enemy who groping of approach that become analysis point is proper and do with recycling bioelectricity signal. Nature model of do living body signal digital analysis chapter as research result could be developed and scientific foundation groping could apply HSS (Hardware-software system) by rehalibitation purpose. Special quality that is done radish form Tuesday of bioelectricity signal formation furthermore studied, and by the result, fundamental process of bodysignal in do structure circuit form of analog - digital water supply height modelling do can.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.113-122
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• 2023

This study was conducted on the premise of the development of cultural products using relic assets of traditional culture in a knowledge and information society led by culture and soft power. It was conducted in the context of exploring the possibility of cultural content products of Wa-Dang relics excavated from traditional architecture in the Unified Silla Period and expanding the scalability of commercialization motifs that are highly useful in jewelry design. First, the original form, material, use, size, meaning, and formative aesthetics of Wa-Dang were identified through literature and media research. Among the considered Wa-Dang, 10 types of Wa-Dang which represent the category and have values in modules and patterns were selected, and, then, circular images were extracted and modularized with a "formal simplification technique." Based on the "mathematical symmetry analysis technique," which is a method of systematizing pattern composition arrangement format. we derived a planar formative element that can be used in the development of the cultural content industry and jewelry design. In order to expand its usability in the jewelry industry in the future, it was presented as a 2D digital image. In the future, we hope more studies on the various cultural content industry utilizing the traditional culture will be carried out.

• The Journal of the Acoustical Society of Korea
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• v.43 no.3
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• pp.361-367
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• 2024

Ultrasound in the air is widely used in industry as a measurement technique to prevent abnormalities in the machinery. Recently, the use of airborne ultrasound imaging techniques, which can find the location of abnormalities using an array transducers, is increasing. A beamforming method that uses the phase difference for each sensor is used to visualize the location of the ultrasonic sound source. We exploit a random sparse ultrasonic array and obtain beamforming power distribution on the source in a certain distance away from the array. Conventional beamforming methods inevitably have limited spatial resolution depending on the number of sensors used and the aperture size. A high-resolution ultrasound imaging technique was implemented by applying functional beamforming as a method to overcome the geometric constraints of the array. The functional beamforming method can be expressed as a generalized beam forming method mathematically, and has the advantage of being able to obtain high-resolution imaging by reducing main-lobe width and side lobes. As a result of observation through computer simulation, it was verified that the resolution of the ultrasonic source in the air was successfully increased by functional beamforming using the ultrasonic sparse array.

• Environmental and Resource Economics Review
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• v.13 no.4
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• pp.735-761
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• 2004

As a possible alternative to Traditional Discounted Cash Flow Method, "Option Pricing Model" has drawn academic attentions for the last a few decades. However, it has failed to replace traditional DCF method practically due to its mathematical complexity. This paper introduces an option pricing valuation model specifically adjusted for the natural resource development projects. We add market information and industry-specific features into the model so that the model remains objective as well as realistic after the adjustment. The following two features of natural resource development projects take central parts in model construction; product price is a unique source of cash flow's uncertainty, and the projects have cost structure from capital-intense industry, in which initial capital cost takes most part of total cost during the projects. To improve the adaptability of Option Pricing Model specifically to the natural resource development projects, we use Two-Factor Model and Long-term Asset Model for the analysis. Although the model introduced in this paper is still simple and reflects limited reality, we expect an improvement in applicability of option pricing method for the evaluation of natural resource development projects can be made through the process taken in this paper.

• Journal of Korea Multimedia Society
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• v.6 no.3
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• pp.444-454
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• 2003

An analysis of heart movement is to estimate a role which supplies blood in human body. We have constructed a left ventricle myocardium model and mathematically evaluated the motion of myocardium. The myocardial motility was visualized using some parameters about cardiac motion. We applied the myocardium model in the gated myocardium SPECT image that showed a cardiac biochemical reaction, and analyzed a motility between the gated myocardium SPECT image and the myocardium model. The myocardium model was created of the based on three dimensional super-ellipsoidal model that was using the sinusoidal function. To express a similar form and motion of the left ventricle myocardium, we calculated parameter functions that gave the changing of motion and form. The LSF algorithm was applied to the myocardium gated SPECT image data and the myocardium model, and finally created a fitting model. Then we analyzed a regional motility direction and size of the gated myocardium SPECT image that was constructed on a fitting model. Furthermore, we implemented the Bull's Eye map that had evaluated the heart function for presentation of regional motility. Using myocardium's motion the evaluation of cardiac function of SPECT was estimated by a contraction ability, perfusion etc. However, it is not any estimation about motility. So, We analyzed the myocardium SPECT's motility of utilizing the myocardium model. We expect that the proposed algorithm should be a useful guideline in the heart functional estimation.

• Journal of KSNVE
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• v.8 no.5
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• pp.964-973
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• 1998

In this paper we propose a levitation and imbalance compensation controller design methodology of magnetic bearing system. In order to achieve levitation and elimination of unbalance vibartion in some operation speed we use the discrete-time Q-parameterization control. When rotor speed p = 0 there are no rotor unbalance, with frequency equals to the rotational speed. So in order to make levitatiom we choose the Q-parameterization controller free parameter Q such that the controller has poles on the unit circle at z = 1. However, when rotor speed p $\neq$ 0 there exist sinusoidal disturbance forces, with frequency equals to the rotational speed. So in order to achieve asymptotic rejection of these disturbance forces, the Q-parameterization controller free parameter Q is chosen such that the controller has poles on the unit circle at z = $exp^{ipTs}$ for a certain speed of rotation p ( $T_s$ is the sampling period). First, we introduce the experimental setup employed in this research. Second, we give a mathematical model for the magnetic bearing in difference equation form. Third, we explain the proposed discrete-time Q-parameterization controller design methodology. The controller free parameter Q is assumed to be a proper stable transfer function. Fourth, we show that the controller free parameter which satisfies the design objectives can be obtained by simply solving a set of linear equations rather than solving a complicated optimization problem. Finally, several simulation and experimental results are obtained to evaluate the proposed controller. The results obtained show the effectiveness of the proposed controller in eliminating the unbalance vibrations at the design speed of rotation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5C
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• pp.664-672
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• 2004

Widespread popularity of wireless data communication devices, coupled with the availability of higher bandwidths, has led to an increased user demand for content-rich media such as images and videos. Since such content often tends to be private, sensitive, or paid for, there exists a requirement for securing such communication. However, solutions that rely only on traditional compute-intensive security mechanisms are unsuitable for resource-constrained wireless and embedded devices. In this paper, we propose a selective partial image encryption scheme for image data hiding , which enables highly efficient secure communication of image data to and from resource constrained wireless devices. The encryption scheme is invoked during the image compression process, with the encryption being performed between the quantizer and the entropy coder stages. Three data selection schemes are proposed： subband selection, data bit selection and random selection. We show that these schemes make secure communication of images feasible for constrained embed-ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of data hiding achieved with the computation requirements imposed on the wireless devices. Experiments conducted on over 500 test images reveal that, by using our techniques, the fraction of data to be encrypted with our scheme varies between 0.0244％ and 0.39％ of the original image size. The peak signal to noise ratios (PSNR) of the encrypted image were observed to vary between about 9.5㏈ to 7.5㏈. In addition, visual test indicate that our schemes are capable of providing a high degree of data hiding with much lower computational costs.

• Food Engineering Progress
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• v.15 no.2
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• pp.136-142
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• 2011

The objective of this research was to classify intact soybeans and foreign objects using near-infrared (NIR) spectroscopy. Intact soybeans and foreign objects were scanned using a NIR spectrometer equipped with scanning monochromator. NIR spectra of intact soybeans and foreign objects in the wavelength range from 900 to 1800 nm were collected. The classification of intact soybeans and foreign objects were conducted by using partial least-square discriminant analysis (PLS-DA) and soft independent modelling of class analogy (SIMCA) multivariate methods. Various types of data pretreatments were tested to develop the classification models. Intact soybeans and foreign objects were successfully classified by the PLS-DA prediction model with mean normalization pretreatment. These results showed the potential of NIR spectroscopy combined with multivariate analysis as a method for classifying intact soybeans and foreign objects.

• The Journal of the Acoustical Society of Korea
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• v.20 no.4
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• pp.22-28
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• 2001

This paper describes the implementation of a robust speaker position location system using the voice signal received by microphone array. To be robust to the reverberation which is the major factor of the performance degradation, low-frequency phase restoration algorithm which eliminates the influence of reverberations using the low-frequency information of the CPSP function is proposed. The implemented real-time system consists of a general purpose DSP (TMS320C31 of Texas instruments), analog part which contains amplifiers and filters, and digital part which is composed of the external memory and 12-bit A/D converter. In the real conference room environment, the implemented system that was constructed by the proposed algorithms showed better performance than the conventional system. The error of the TDOA estimation reduced more than 15 samples.