• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.149-152
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• 1999

This paper addresses major issues in localising sound sources in space using the experimental data set of head-related responses in the time or frequency domain. They come from the technical realisation steps for implementing the convolution of HRIR's with sound sources, the cross-talk cancellation for transaural filtering, the matched time delay compensation, etc. in real, those technical matters seem to be minor because they can be realised in off-line signal processing schemes. This paper puts much emphasis on what we misunderstood about the sets of HRTF's or HRIR's, More specifcaily, the sets of HRTF's or HRIR's of course supply relevant information to sound localisation but include much useless 'rubbish' that have made for us to fail to put spatial image into real souno signals such as voices and music's. This paper proposes possible reasons for such failure and, furthermore, introduces detained subjects that should be challenged so as to resolve them.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.4
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• pp.131-136
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• 2016

Horizontal geothermal heat exchanger is affected by various factors such as pipe length, soil temperature, and outdoor environment. Simulation program is convenient for responding to various factors. The objective of this study was to determine the feasibility of using EnergyPlus to predict exit air temperature through horizontal geothermal heat exchanger in domestic. The correlation coefficient between EnergyPlus results and experimental results was 0.825. The correlation coefficient between EnergyPlus results and mathematical results was 0.722, indicating "The two values can based on Lousi on values can be Our results indicate that it is possible to use EnergyPlus to predict exit air temperature through horizontal geothermal heat exchanger.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.110-112
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• 1993

Acidic polysaccharide from Korean red ginseng was found to inhibit pancreatic lipase activity and cause reduction of plasma triglyceride level after oral administration of corn oil emulsion to rats. Thus acidic polysaccharide may reduce plasma triglyceride through its inhibitory action on pancreatic lipase and successive inhibition of intestinal absorption of fat due to reduction of lipolysis. In the course of this experiment, we found an unknown ninhydrin positive substance in Korean red ginseng. The unknown substance was identified to be arginyl-fructosyl glucose(Arg - Fru - Glc). Coment of this new compound was $5.37\%$ in Korean red ginseng powder. Sucrase and maltase activities in mucous layer of rat jejunum were found to be inhibited by Arg-Fru-Glc. Physiological significance of the new compound was discussed based on these experimental results.

• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.383-388
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• 2009

In this paper we propose a variance function estimation method based on kernel trick for replicated data or data consisted of sample variances. Newton-Raphson method is used to obtain associated parameter vector. Furthermore, the generalized approximate cross validation function is introduced to select the hyper-parameters which affect the performance of the proposed variance function estimation method. Experimental results are then presented which illustrate the performance of the proposed procedure.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.1
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• pp.38-44
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• 1984

Subnanosecond optical pulses with 0.8-1.Bum wavelength are generated by experimentally realizing a single pass fiber Raman laser. This fiber Raman laser is pumped by a mode-locked and Q-switched Nd-YAG laser. Two wave sum frequency phenomenon is also obsenred in the course of the experimental work. The fiber Raman laser is then used to measure dispersion characteristics of a sin\ulcorner mode fiber in the long-wavelength lesion.

• Smart Structures and Systems
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• v.19 no.4
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• pp.431-439
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• 2017

This investigation is aimed to develop a model of experimental-computation determination of a support moment of a cantilever beam loaded with concentrated force at its end including the optimal choice of coordinates of deflection data points and parameters of transformation of deflection data in case of insufficient accuracy of the assignment of initial parameters (support settlement, angle of rotation of the bearing section) and cantilever beam length. The influence of distribution and characteristics of sensors on the cantilever beam on the accuracy of determining the support moment which improves in the course of transition from the uniform distribution of sensors to optimal non-uniform distribution is shown. On the basis of the theory of inverse problems the method of transformation reduction at numerical differentiation of deflection functions has been studied. For engineering evaluation formulae of uncertainty estimate to determine a support moment of a cantilever beam at predetermined uncertainty of measurements using sensors have been obtained.

• International Journal of Fluid Machinery and Systems
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• v.2 no.4
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• pp.426-430
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• 2009

In order to investigate the design method for a micro centrifugal compressor, which is the most important component of an ultra micro gas turbine, an impeller having the outer diameter of 20mm was designed, manufactured and tested. The designed rotational speed is 500,000 rpm and the impeller has a fully 3-dimensional shape. The impeller was rotated at 250,000 rpm in the present study. The experimental results of the tested compressor with the vaned and the vaneless diffusers were compared. It was found that the vaned diffuser attained the higher flow rate than the vaneless diffuser at the maximum pressure ratio. In addition the maximum pressure ratio was higher for the diffuser having a larger diffuser divergence angle at the high flow rate. These results were compared with those obtained by the prediction method used at the design stage.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.313-313
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• 2000

Recently the number of lectures of offered as part of distance education courses is increasing due to the necessity of continuing education in this era of rapidly changing technologies. To promote this, Web-based distance education systems have been developed and put into practical use. To step further, we propose a virtual space, distance education platform called interactive virtual laboratory. The proposed system is expected to overcome many obstacles in performing the unit operations laboratory at the current setting. The server/client system implementation was programmed with ASP and Visual Basic. The availability of simple and efficient technological supports for dissemination and remote use of virtual lab systems supports more experimental practices regardless of the number of participating students and their locations. Variety of instruments, process equipments and lab procedures are being added to make it a complete package of virtual lab fur undergraduate unit operations course.

• Journal of Engineering Education Research
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• v.14 no.6
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• pp.67-72
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• 2011

This method is a new experimental model for a mathematical education in Engineering students. We compare two different classes; one was recorded the lecture with scenario and the other was not. Also we set up the detailed structures in every lecture for mathematical modeling and solving parts. The purpose for a new model is 1) to improve the students's ability to solve the mathematical problem, 2) how to approach to getting a solution for each problem by system and 3) to provide the lectures anytime to students who want to study more mathematics.

• Journal of radiological science and technology
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• v.9 no.1
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• pp.65-71
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• 1986

It is an experimental report about optimum window-width on radionuclides $^{99m}Tc$ and $^{131}I$ and obtained results as follows; 1. In case of $^{99m}Tc$, a) The difference of counting rate in each window-width is greater at the below 20% window than above 20% window-width. b) BKG counting is proportionated to the window-width. 2. In case of $^{131}I$, a) The counting rate increased according to the window-width but the increasing course is not equal in all window. The difference of counting rate is greater at the below of 20% window-width than above 20% window. b) BKG counting is proportionated to the window-width.