• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.1-9
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• 2002

This study was performed to investigate vibration generated from machines that were used at factories and construction works. Vibrations were measured at three points in a straight line based on distance from the vibration sources, and analyzed to assess the vibration bevels. The average vibration level of factory machines was 65.4dBV at 2m, and that of construction machines was 74.0dBV at 5m. Vibration attenuations was 4.0~8.2dBV by double distance. All such data were applied to gain coefficients of attenuation equations for predicting vibration level by distance from the vibration sources. Data recorded on tapes were analyzed to understand the characteristics of frequency because these characteristics are important factors to design a Plan for installing the vibration-Proof devices. Finally, considering results from these analysis, assessment, and prediction, the methods for reducing vibration generated from machines were discussed.

• Journal of Distribution Science
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• v.13 no.3
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• pp.21-29
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• 2015

Purpose - This paper addresses the role of designers in design-oriented firms and how they should work together with other organization members. The aim of this paper is to investigate how designers generate ideas and cooperate with others as well as how their participation in decision-making reflects on corporate design strategies. Research design, data, and methodology - An in-depth exploratory study examined how designers actually perform their roles in enterprises; in addition, information, knowledge, communication among designers, and sources of creativity were examined. Hanssem and Ikea grew as design-intensive businesses in a declining industry. Data were obtained from interviews with the design staff of each company as well as secondary sources. Results - Designers were found to use their designs to communicate with customers as well as with communities outside of the enterprise; they also participated in overall decision-making in relation to important design strategies. Conclusions - This study emphasized the increasing importance of the innovative and creative role of designers; thus, it might substantially help companies to develop their own design capabilities and deploy design strategies.

• Journal of Nutrition and Health
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• v.24 no.6
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• pp.534-546
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• 1991

Three-day dietary records data from 237 college students(male 65, female 172) were used as the basis to estimate total dietary fiber(DF) intake of Korean adults & to investigate the major food sources of fiber. Mean daily DF intake of the subjects was 15.2$\pm$3.7g range being 7.5-34g When related to energy intake women consume more DF(7.7$\pm$1.5/1000kcal) than men(6.8$\pm$1.7g/1000kcal) Mean daily crude fiber(CF) intake of the subjects was 6.2$\pm$2.4g The mean DF:CF ratio for the subjects was 2.5$\pm$0.5 indicating that DF intake is 2-3 times of CF intakes The intakes of the two measures of fiber were highly correlated(r=0.791) The major food sources for DF in Korean are vegetables cereals and fruits and 14.3% respectively In comparision with limited international data on the DF intake by adults DF intake by the subjects was similar to those of developed countries. Present study indicates that DF intakes of the subjects are considerably lower than recommended level and they need to consume more DF than the present level.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1985-1991
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• 1999

In this paper, complete and general two-port lumped Spice-network model is developed for a lossy transmission line. This model is realized as a Spice subcircuit, by means of standard lumped network elements and mathematical functions. It is used as a component in the time-domain simulation of a high-speed data transmission line such as IMI(Inter Module Interface) data path in HANbit ACE 64 ATM switching system. The only required Spice network elements are resistance and frequency-dependent controlled-voltage sources. Such frequency-dependent sources are realized by utilizing the standard Hspice mathematical functions FREQ, DELAY, and POLY.

• Journal of The Korean Astronomical Society
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• v.39 no.4
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• pp.151-155
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• 2006

Long slit spectrometers are widely used in optical and infrared bands in astronomy. Absolute flux calibration for extended sources, however, is not straightforward, because a portion of the radiation energy from a flux calibration star is blocked by the narrow slit width. Assuming that the point spread function(PSF) of the star is circularly symmetric, we develop a robust method to extrapolate the detected stellar flux to the unobscured flux using the measured PSF along the slit-length direction. We apply this method to our long slit data and prove that the uncertainty of the absolute flux calibration is less than a few percents.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.241-244
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• 2000

This paper addresses a new method of blind source separation (BSS) when sources are nonstationary signals. Our method requires only multiple correlation matrices of the observed data at several time-windowed data frames to estimate the mixing matrix. In contrast to most existing BSS methods where higher-order statistics is necessary, our method is based on only second-order statistics. In the framework of correlation matching, we develop a new BSS algorithm. The useful behavior of the proposed method is verified by numerical experiments.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.2
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• pp.220-230
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• 2005

The purpose of this study was to compare clothing benefits and the types of fashion information sources according to family life cycle. Subjects were selected through stratified sampling technique in Seoul and suburban area. Collection of the research data was made using a self-administered questionnaire survey. Factor analysis, ANOVA, and Duncan test were used to conduct the data analysis on 562 out of 600 questionnaires. Clothing benefit variables were reduced to five factors : fashion/social status, individuality, function/comfort, figure flaws compensation, and economic value. The result showed significant differences on 3 clothing benefits(fashion/social status, individuality, and function/comfort) and 5 fashion information soures (celebrities, street fashion, T.V commercial, Internet/home shopping, fashion catalog) according to family life cycle.

• Nuclear Engineering and Technology
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• v.30 no.6
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• pp.496-506
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• 1998

This paper deals with the computational modeling of buoyancy-driven turbulent heat transfer involving spatially uniform volumetric heat sources in semicircular geometry. The Launder & Sharma low-Reynolds number k-$\varepsilon$ turbulence model without any modifications and the SIMPLER computational algorithm were used for the numerical modeling, which was incorporated into the new computer code CORE-TNC. This computer code was subsequently benchmarked with the Mini-ACOPO experimental data in the modified Rayleigh number range of 2$\times$10$^{13}$ $\times$10$^{14}$ . The general trends of the velocity and temperature fields were well predicted by the model used, and the calculated isotherm patterns were found to be very similiar to those observed in previous experimental investigations. The deviation between the Mini-ACOPO experimental data and the corresponding numerical results obtained with CORE-TNC for the average Nusselt number was less than 30% using fine grid in the near-wall region and the three-point difference formula for the wall temperature gradient. With isothermal pool boundaries, heat was convected predominantly to the upper and adjacent lateral surfaces, and the bottom surface received smaller heat fluxes.

• Journal of Korea Multimedia Society
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• v.25 no.11
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• pp.1572-1581
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• 2022

Energy conversion to renewable energy is being promoted to solve the recently serious environmental pollution problem. Solar energy is one of the promising natural renewable energy sources. Compared to other energy sources, it is receiving great attention because it has less ecological impact and is sustainable. It is important to predict power generation at a future time in order to maximize the output of solar energy and ensure the stability and variability of power. In this paper, solar power generation data and sensor data were used. Using the PCC(Pearson Correlation Coefficient) analysis method, factors with a large correlation with power generation were derived and applied to the GAM(Generalized Additive Model). And the prediction accuracy of the power generation prediction model was judged. It aims to derive efficient solar power generation in the future and improve power generation performance.

• Journal of Ocean Engineering and Technology
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• v.33 no.4
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• pp.358-363
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• 2019

The acoustic power is used as a primary index characterizing underwater sound sources and could be defined by its source level. The source level has been assessed using various experimental techniques such as the reverberation time method and reverberant tank plot method. While the reverberation time method requires reverberation time data extracted in a preliminary experiment in a reverberant water tank, the reverberant tank plot method only needs acoustic pressure data directly obtained at the reverberation water tank. In this research, these experimental techniques were studied in comparative experiments to estimate the source levels of underwater sources in a reverberant water tank. This paper summarizes the basic theories and procedures of these experimental techniques and presents the experimental results for an underwater source in a long cuboid water tank using each technique, along with a discussion.