• The Journal of the Acoustical Society of Korea
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• v.22 no.1
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• pp.69-77
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• 2003

Measurements of backscattered intensity were made over a shallow water using 300 ㎑and 1200 ㎑ bottom mounted ADCP (Acoustic Doppler Current Profiler) to determine the temporal variability of vertical distribution of high-frequency volume scattering strength (Sv). The variability of Sv in relatively deep water column(85 m and 113 m was due to the daily vertical migration, probably of larger zooplankton. However it was not found with 1200㎑ data at shallow water column. From the empirical orthogonal function (EOF) analysis using 1200㎑ data, the vertical distribution of the first mode eigenvectors of Sv is characterized by the presence of the maximum values near the bottom of the water.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.2
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• pp.11-17
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• 2009

Terrestrial LiDAR can measure high capacity 3D-topography coordinates and try to apply to various public works such as tunnel surveying, facility deformation surveying. This experiment is about how to calculate ground cutting volume because the stage of the earth work spend lots of money and time among civil engineering works. Surveying cutting area using Terrestrial LiDAR and then calculating cutting area in planned area comparing sectional plan before construction and planned section and LiDAR data. Also, the values of the calculating ground cutting volume by three different resolution LiDAR has are compared and analyzed.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.652-657
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• 2007

This paper is an interim report on the investigation of thermodynamic properties of $CO_2$/oil mixture refrigerant. First, liquid density of POE (poly-ol ester) and PAG (poly alkylene glycol) were measured and expressed as a function of temperature. Then, a solubility equation was developed which enables us to calculate the weight fraction of $CO_2$ for the mixture in a liquid state. An experimental apparatus with a cell was constructed to measure P-$\upsilon$-T-$\chi$ data for $CO_2$/oil mixture. The volume of the cell was determined using a certain formula considering change in volume as a function of temperature and pressure. Then, experimental data were obtained over the temperatures $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, $70^{\circ}C$ and $80^{\circ}C$ with various mole fractions. Finally, assuming a primitive model of ideal gas, the volume of $CO_2$/oil mixture was predicted with a relatively larger error of 5.05% for $CO_2$/PAG and 8.81% for $CO_2$/POE. The volume of $CO_2$/oil mixtures would be better predicted using an appropriate equation of state, of which results will be reported soon.

• Journal of the Optical Society of Korea
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• v.15 no.1
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• pp.96-102
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• 2011

Simultaneous measurements using a scanning spectrograph system and transmissometer were performed for the first time over an urban site in Gwangju, Korea, to derive the ambient $NO_2$ volume mixing ratio. The differential slant column densities retrieved from the scanning spectrograph system were converted to volume mixing ratios using the light traveling distance along the scanning line of sight derived from the transmissometer light extinction coefficients. To assess the performance of this system, we compared the derived $NO_2$ volume mixing ratios with those measured by an in situ chemiluminescence monitor under various atmospheric conditions. For a cloudless atmosphere, the linear correlation coefficient (R) between the two data sets (i.e., data derived from the scanning spectrograph and from the in situ monitor) was 0.81; the value for a cloudy atmosphere was 0.69. The two sets of $NO_2$ volume mixing ratios were also compared for various wind speeds. We also consider the measurement errors, as estimated from an error propagation analysis.

• Journal of Korea Multimedia Society
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• v.22 no.5
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• pp.588-600
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• 2019

Each year Malaria affects over 200 million people worldwide. Particularly, African continent is highly hit by this disease. According to many researches, this continent is ideal for Anopheles mosquitoes which transmit Malaria parasites to thrive. Rainfall volume is one of the major factor favoring the development of these Anopheles in the tropical Sub-Sahara Africa (SSA). However, the surveillance, monitoring and reporting of this epidemic is still poor and bureaucratic only. In our paper, we proposed a method to fast monitor and report Malaria instances by using Social Network Systems (SNS) and precipitation volume in Nigeria. We used Twitter search Application Programming Interface (API) to live-stream Twitter messages mentioning Malaria, preprocessed those Tweets and classified them into Malaria cases in Nigeria by using Support Vector Machine (SVM) classification algorithm and compared those Malaria cases with average precipitation volume. The comparison yielded a correlation of 0.75 between Malaria cases recorded by using Twitter and average precipitations in Nigeria. To ensure the certainty of our classification algorithm, we used an oversampling technique and eliminated the imbalance in our training Tweets.

• The Korean Journal of Applied Statistics
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• v.34 no.5
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• pp.773-794
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• 2021

Prediction of vehicle traffic volume is very important in planning municipal administration. It may help promote social and economic interests and also prevent traffic congestion costs. Traffic volume as a time-varying trajectory is considered as functional data. In this paper we study three functional regression models that can be used to predict an unseen trajectory of traffic volume based on already observed trajectories. We apply the methods to highway tollgate traffic volume data collected at some tollgates in Seoul, Chuncheon and Gangneung. We compare the prediction errors of the three models to find the best one for each of the three tollgate traffic volumes.

• Journal of Technologic Dentistry
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• v.45 no.2
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• pp.48-53
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• 2023

Purpose: This study aimed to provide the basic data for dental barrel finishing by observing the abrasiveness of the metal body according to the time of the barrel finishing. Methods: This study included three types of Co-Cr alloys. The specimens were manufactured by casting method using 10-mm diameter wax spheres (n=10). The cast alloys were polished for 60 minutes at intervals of 5 minutes in barrel finishing. The weight and volume of the specimens were measured, and the rate of change was calculated. The data obtained from the three groups (α=0.05) were compared and analyzed using one-way ANOVA. Results: As a result, the overall volume and weight of the group decreased after grinding compared with the control group. Conclusion: When grinding dental barrel finishing, no difference was observed in the processing rate depending on the type of alloy and the processing rate of the alloy body is within 30 minutes; hence, dental barrel finishing can be effectively used for grinding.

• Korea Journal of Hospital Management
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• v.21 no.1
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• pp.51-61
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• 2016

This study attempted to investigate how mass media marketing of a hospital influences patient volume. Additionally, the association of patient volume with exposure time and the type of mass media was examined. Data from a university hospital in Bundang (from January 2014 to November 2014) were used. Degree of physicians' mass media marketing was measured by the number of media exposure. Linear mixed model for repeated measures data was run to identify the associations between the number of media exposure and patient volume. First, the number of hospital physician's mass media exposure and new patients and the first visit patients were positively associated. Second, broadcasting media which has relatively significant in patient volume is TV programs such as cultural programs and news. Third, hospital physicians with higher ranks who were exposed to press media receive more patient appointment. Also, nonsurgical hospital physicians who were exposed to press media receive more patients. Fourth, medical treatment activities for hospital staff who hold the rank of Professor in case of making an appearance at press media have relatively increased. Hospital physician's media exposure, particularly TV programs, was significantly related to patient volume for outpatients.

• Journal of KIISE:Computing Practices and Letters
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• v.12 no.5
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• pp.286-299
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• 2006

Due to the continuing technical progress in the capabilities of modeling, simulation, and sensor devices, huge volume data with very high resolution are common. In scientific visualization, various interactive real-time techniques on high performance parallel computers to effectively render such large scale volume data sets have been proposed. In this paper, we present a mobile volume visualization system that consists of mobile clients, gateways, and parallel rendering servers. The mobile clients allow to explore the regions of interests adaptively in higher resolution level as well as specify rendering / viewing parameters interactively which are sent to parallel rendering server. The gateways play a role in managing requests / responses between mobile clients and parallel rendering servers for stable services. The parallel rendering servers visualize the specified sub-volume with rendering contexts from clients and then transfer the high quality final images back. This proposed system lets multi-users with PDA simultaneously share commonly interesting parts of huge volume, rendering contexts, and final images through CSCW(Computer Supported Cooperative Work) mode.

• Journal of Biomedical Engineering Research
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• v.20 no.4
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• pp.409-417
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• 1999

Talairach atlas consists of three orthogonal sets of coronal, sagittal, and axial slices. This atlas has recently an important role as a standard brain atlas in diagnosing disease related with brain function and analyzing cause of brain disease. The 3D digital volume data set reconstructed from the atlas is widely applied to visualization and quantitative analysis of results processed in the digital computer. This paper represented application method of bi-linear interpolation technique, proposed tri-planar interpolation algorithm for 3D volume data reconstruction of Talairach atlas. And we implemented Talairach atlas editor and discussed problems in volume reconstruction of Talairach atlas. The bi-linear method was applied to only one set of the slices and considered the on intensity value in the interpolation process. The tri-planar technique concurrently uses three orthogonal sets of slices with the same information of brain structures. Talairach atlas editor visualized three sets. of atlas slices on the same coordinate and had editing function. Using the atlas editor, we represented problems in volume reconstruction by showing inconsistency of brain structures among three sets of atlas slices.