• Particle and aerosol research
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• v.10 no.1
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• pp.1-8
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• 2014

In this study, we have developed a real-time monitoring device for measuring $PM_{10/2.5/1}$ of ambient aerosol particles. The real-time PM (Particulate Matter) monitor was based on the light scattering method and had 16 channels in particle size. The laboratory and field tests were carried out to evaluate the performance of the PM monitor developed. Arizona Road Dust particles ranging from diameter of 0.1 to $20{\mu}m$ were generated as test particles in the laboratory test. The field test was carried out at the Seoul Meteorological Observatory. We can obtain the particle size and number concentration (particle size distribution) only from the real-time PM monitor developed. Therefore, the average density of aerosol particles was used to obtain the PM data from the particle size distribution. The $PM_{10/2.5/1}$ results of the PM monitor were compared with the data of the Grimm Dust Monitor (Model 1.108) and a beta ray gauge (Thermo Fisher Scientific). As a result, it was shown that the $PM_{10/2.5/1}$ results obtained by the real-time PM monitor agreed well with the data of the reference devices, and overall, the real-time PM monitor could be used as a PM monitoring device for real-time monitoring of the ambient particles.

• Journal of Korean Foot and Ankle Society
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• v.10 no.1
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• pp.80-83
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• 2006

Purpose: To compare ultrasonographic size of morton's neuroma measured to actual size. Materials and Methods: Thirty-two (twenty-eight patients) of symptomic Morton's neuroma were measured by ultrasonography preoperatively and by manual method that designed by authors intraoperatively from January, 2002 to May, 2003. Two results were stastically compared by paired T-test. Results: Except one, all of cases were women and the mean age of patients was 50.6 years (32-62 years). The most common associated disease was hallux valgus deformity (17 cases). Six of Morton's neuromas located on second intermetatarsal space, sixteen of them did third intemetatarsal space and ten of neuromas located simultaneously second and third intermetatarsal space. The ultrasonographic size of neuroma averaged 3.48 mm and real size was 3.99 mm. The size checked by manual method was larger than by ultrasound with statical meaning. Conclusion: The size of Morton's interdigital neuroma checked by ultrasonography on plantar aspect is smaller than real size. If you checked Morton's interdigital neuroma size by ultrasonography, you can suspect that real size of Morton's interdigital neuroma is larger than that size.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.416-427
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• 2018

As the loan size of real estate PF is huge, its market ripple effect gets bigger when overdue occurs. Accordingly, the management of the delinquency rate and macroeconomic analysis are required. As the preceding research mainly proceeded with microeconomic analysis through the real estate PF data of individual banks to evaluate importance of list or analyzed core factors for delinquency, it lacked research on comprehensive real estate PF size. In order to overcome the limitations of such data, this research studied real estate PF delinquency rate of the entire market and effect relationship by the size. The research utilized the size of real estate PF loans, money supply, interest rate, consumer price index(CPI), and GDP data. Also, it applied the first model of VECM as linear relationship between at least two or more variables, following the result of co-integration test. As a result of Granger-causality test, the real estate PF loans delinquency rate is influenced by their loan size, and as a result of impulse response analysis, the interest rate is shown to be affecting delinquency rate the most. Interest rate could risesomeday and aggravate the delinquency rate of real estate PF. Also, risk exposure could be serious as the loan size increases.Therefore, the management of real estate PF delinquency rate requires continuous monitoring, tracking and observing issued loans from a macro point of view. The plans to prevent delinquency will be necessary.

• Journal of Positioning, Navigation, and Timing
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• v.9 no.2
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• pp.131-138
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• 2020

In this paper, we analyze the delay phenomenon that can occur when controlling an unmanned aerial vehicle using a camera and describe a solution to solve the phenomenon. The group of pictures (GOP) value is changed in order to reduce the delay according to the frame data size that can occur in the moving image data transmission. The appropriate GOP values were determined through experimental data accumulation and validated through camera self-test, system integration laboratory (SIL) verification test and system integration test.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.357-361
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• 2008

Although power analysis is of important tool of research, investigators in veterinary medicine are unaware of the concepts of the statistical power. Two types of error occur in classical hypothesis testing and, those errors should be avoided, if possible. Since power is highly dependent on the sample size, whenever declaring non-statistically significant result they should consider the potential for committing a Type II error in their studies, which refers to the probability of falsely stating that two treatments are equivalent despite true difference between them. Also, sample size determination is one of the most important tasks facing the researcher when planning a diagnostic study, and provides valuable information on the characteristics of a test performance. This type of analysis forms the basis for proper interpretation of test results. The aim of this article was to re-evaluate some selected studies on diagnostic test reported in the domestic veterinary publications to determine the power and necessary sample size for inequality testing to ensure the desired power. Power calculations were illustrated using real-life examples of comparison of a new test and a reference test for detecting antibodies of various animal diseases. Factors affecting to the power were also discussed.

• Particle and aerosol research
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• v.14 no.4
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• pp.107-119
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• 2018

In this study, we have developed a real-time monitoring device for measuring PM10 and PM2.5 of ambient aerosol particles. The real-time PM monitor (SENTRY Dust Monitor) uses the optical scattering method and has 16 channels in particle size. The laboratory and field tests were carried out to evaluate the developed SENTRY Dust Monitor. Arizona Test Dust particles were used as test particles in the laboratory test and the field test was carried out at the Jongno-gu Observatory in Seoul. The measurements of PM10 and PM2.5 concentrations obtained by SENTTRY Dust Monitor were compared with Grimm Dust Monitor (Model 1.108) and a beta ray gauge. It was shown that the PM10 and PM2.5 concentrations obtained by SENTRY Dust Monitor agree well with that of the reference devices. Based on the results obtained in this study, it could be concluded that the SENTRY Dust Monitor can be used as a PM monitoring device for real-time monitoring of the ambient aerosols.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.04a
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• pp.391-398
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• 2000

To evaluate the seismic performance of a base isolated building accurate analytical model should be selected. The analytical results such as reduced accelerations member forces and relative displacements of the superstructure of the base isolated building are only meaningful when the analytical model is close enough to the real structure. Real size one bay-two story steel frame and two kinds of seismic isolators(laminated elastomeric bearing and lead-rubber bearing) are designed. manufactured and constructed in the laboratory. Free vibration tests using fuse bars were conducted to evaluate the change of dynamic characteristics(period and damping) before and after base isolation of the steel frame. The experimental results of free vibration tests were also used as a bench mark for adjusting the selected analytical modeling to real base isolated steel frame.

• Journal of the Ergonomics Society of Korea
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• v.17 no.2
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• pp.49-63
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• 1998

The purpose of this study is to study real body size and ideal body shape by considering the degree of satisfaction of body part and understanding body size by the degree of leanness/obesity. The subjects in this study were 420 males from 18 to 25 years old. Body measurements and surveys were taken and analyzed by mean, standard variation, correlation analysis, regression analysis, crosstabulation analysis, cluster analysis, one-way ANOVA, and Duncan's Test. The results of analyses indicate that the subjects tended to be satisfied with thick chest and upper limbs, wide shoulder width, and preferred to be tall and have big hands and feet. By cluster analysis of 19 variables, the subjects were divided into 4 groups, each consisting 41, 138, 134, and 47 males. Because the 19 variables were body measurements transformed to eliminate the body size factor, this classification was considered to express how lean or how obese a human body appears. The results of one way ANOVA and Duncan's Test indicate that, according to the degree of leanness/obesity from Group I (lean tendency) to Group IV(obese tendency), characteristics of the body shape changed as follows; height became lower, limbs became shorter, trunk and limbs became thicker and weight became heavier. Also it showed that Group IV were most satisfied with chest girth, upper limb girth and shoulder width and Group I with height, hip girth and waist girth.

• Tribology and Lubricants
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• v.24 no.2
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• pp.82-89
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• 2008

The purpose of this study is to develop the proto type sensor installed inside an oil filter in order to detect oil deterioration level. The sensor is made up with two concentric cylinders with constant gap in between and a filter element inside the central area. The size will be designed as similar as real oil filters. The sensor will be tested on a test rig, which is circulating engine oil, with the same size of an oil filter adapting housing as real engines'. It will be measured the capacitance of a sample engine oil, then be able to be gotten the dielectric constant. The changes in the dielectric constant could be correlated with the engine oil deterioration level if the sensor development would be completed. In this paper, it will be shown the test results carrying out under variable temperature conditions at atmosphere pressure.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1126-1133
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• 2005

The effects of mean particle size and uniformity coefficient of dredged soils to the liquefaction resistance strength and dynamic characteristics are experimentally studied in this paper. Representative 4 mean particle sizes and 3 uniformity coefficients were selected and 12 representative particle size distribution curves which have different mean particle sizes and uniformity coefficients, were artificially manufactured using the real dredged river soil. Cyclic triaxial tests and torsional shear tests were carried out to analyze the effect of mean particle size and uniformity coefficient to the liquefaction resistance strength and dynamic characteristics of soils.