• Journal of Sensor Science and Technology
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• 제16권4호
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• pp.254-258
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• 2007

A novel cure sensor based on the side-polished single mode fiber has been proposed and demonstrated. Two different UV curable epoxies were used to verify the feasibility of the side-polished single mode fiber as a high sensitivity cure sensor. The volume change of the epoxy by UV curing results in a corresponding change of the refractive index. The sensor can be used to monitor the curing process, the refractive index variation and the volume change of epoxy in real time during the UV curing process. In addition, small birefringence of the epoxy film can be detected using the sensor.

• Journal of Magnetics
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• 제18권3호
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• pp.276-282
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• 2013

In this paper, magnetic flux distributions of several permanent magnet arrays, including Halbach array, are analyzed and compared. Also, braking force characteristics on a moving solid conductor in the eddy current brake systems with such magnet arrays are analyzed. Then, a new performance index taking into account the maximum braking force and the volume of the magnet is introduced for the comparison and case study of permanent magnet arrays. By changing the lengths, magnetization directions and the height of the permanent magnet arrays, a higher braking force per volume of the magnet can be achieved.

• Journal of ILASS-Korea
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• 제24권3호
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• pp.122-129
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• 2019

Flow uniformity in aftertreatment system is an important factor in determining uniform catalytic reaction and filtration. In this study, variety types of DOC-DPF system design were analyzed to increase flow uniformity. For this analysis, ANSYS Fluent was used with porous media setup for DOC and DPF. Turbulent flow was modeled by standard $k-{\varepsilon}$ model excepting porous media. Uniformity index was utilized to evaluate the flow uniformity quantitatively. Reference design showed low velocity region because two large vortex were generated before baffle. When radius of DOC-DPF system was increased, exhaust pressure acting on the inlet decreases and velocity distribution was shifted to one side. When inlet pipe was set to axial center of DOC-DPF system velocity distribution was symmetric. However, flow was not dissipated until the front end of DOC and showed higher uniformity index. When the volume of DOC was reduced while fixed volume of entire DOC-DPF system and baffle plate is located downstream of the DOC-DPF system, there was improvement in uniformity index.

• Journal of the Korean Dietetic Association
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• 제19권1호
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• pp.25-33
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• 2013

We examined the perception of volume in college students with a normal weight versus those students with obesity. College students were divided into a normal weight group (<23 body mass index, n=121) and an obese group (${\geq}23$ body mass index, n=110), The perception of volume was measured under different beverage colors (colorless, black, yellow, and blue) and cup colors (colorless, black, yellow, and blue) containing the same amount of liquid (150 ml). We found that the normal weight group perceived significantly more liquid in a cup with a blue beverage versus a colorless one. The obese group perceived significantly more liquid in a cup with a yellow or blue beverage versus a colorless one. In terms of cup color, the normal weight group perceived significantly more liquid in a black color cup compared to a blue color cup. However, there were no differences in perceived volume according to the color of cup among the obese group. There were no significant differences in the perceived volume between the normal and obese group under all conditions tested. In conclusion, beverage and cup color effects volume perception in normal weight students, while only beverage color effects volume perception in obese students. Therefore, controlling, the color of beverages and cups may help to control the consumption of drinks.

• The Korean Journal of Applied Statistics
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• 제35권1호
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• pp.93-104
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• 2022

In forecasting realized volatility of the major US stock price indexes (S&P 500, Russell 2000, DJIA, Nasdaq 100), internet search volume reflecting investor's interests and implied volatility are used to improve forecast via a deep learning method of the LSTM. The LSTM method combined with search volume index produces better forecasts than existing standard methods of the vector autoregressive (VAR) and the vector error correction (VEC) models. It also beats the recently proposed vector error correction heterogeneous autoregressive (VECHAR) model which takes advantage of the cointegration relation between realized volatility and implied volatility.

• Journal of the Korea Safety Management & Science
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• 제12권4호
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• pp.255-263
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• 2010

The research developes short-run standardized control charts(SSCC) and short-run acceptance control charts(SACC) under the various demand patterns. The demand patterns considered in this paper are three types such as high-variety and repetitive low-volume pattern, extremely-high-variety and nonrepetitive low-volume pattern, and high-variety and extremely-low-volume pattern. The short-run standardized control charts developed by extending the long-run ${\bar{x}}$-R, ${\bar{x}}$-s and I-MR charts have strengths for practioners to understand and use easily. Moreover, the short-range acceptance control charts developed in the study can be efficiently used through combining the functions of the inspection and control chart. The weighting schemes such as Shewhart, moving average (MA) and exponentially weighted moving average (EWMA) can be considered by the reliability of data sets. The two types according to the use of control chart are presented in the short-range standardized charts and acceptance control charts. Finally, process capability index(PCI) and process performance index(PPI) classified by the demand patterns are presented.

• Journal of Korean Society of Forest Science
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• 제105권3호
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• pp.330-335
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• 2016

This study was conducted to derive merchantable volume ratio for 5 major species such as Pinus Densiflora (Central Region). The data used for this study was from at least more than 1,300 trees of research data throughout the country. the study applied two estimation equations, which were the estimation equation for wood volume ratio representing total wood volume to total tree stem volume and the estimation equation for merchantability representing ratio of merchantable volume to total wood volume. The merchantable volume ratio was derived by multiplying those two estimation equations. In order to gain wood volume ratio(W) from DBH, $W=\frac{a_1}{1+a_2/D}+\frac{b_1}{1+b_2/D}$ model was used. Fitness index of it was more than 99% by species, and other test statistics also indicated the suitability of this equation enough. Merchantability (M) for wood volume applied $M=e^{a_1\(\frac{d}{D}\)^{a_2}}-(b_0+b_1D+b_2D^2+b_3D^3)$ model and fitness index was more than 96% by species. Merchantable volume ratio was assessed using those two estimation equations by each 5 species, and constructed a merchantable volume ratio table. In result, merchuntable volume ratio was little difference between stand types, but there was slightly different with the existing standard such as conifers of 85% and non-conifers of 70%.

• The Journal of the Korea Contents Association
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• 제12권6호
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• pp.338-345
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• 2012

Benign prostatic hyperplasia (BPH) is increasing in Korea owing to the westernized eating habits and changes in living environment. However, very few studies have been made to determine the standard value of the prostate volume as a diagnostic reference. Also, most of the previous studies have been focusing on the elder population over 40 years old. This study retrospectively analyzes the results of prostate volume measured by transrectal ultrasonography in the healthy Korean men in their 30's who visited our institution's center for health promotion for routine checkups. The mean age of the total of 157 men enrolled was $34.6{\pm}2.9$ years, and the mean prostate volume was $19.4{\pm}4.0ml$. Prostate volume of these men was correlates proportionally to their age, prostate specific antigen, body mass index, body surface area, and abdominal girth. Among these, the strongest correlation is between the prostate volume and the abdominal girth (r=0.317, p<0.001).

• Journal of the East Asian Society of Dietary Life
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• 제21권6호
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• pp.863-870
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• 2011

In this study, muffins containing Bokbunja, popularly known as a psychological activator and functional material, was made, and its preference levels and qualitative characteristics were evaluated. We measured the height and weight of muffins containing Bokbunja powder. Height decreased when the volume of Bokbunja powder increased (p<0.001). When weight was measured, there was no meaningful difference between the samples, although the Bokbunja powder-containing samples were heavier than the samples not containing Bokbunja powder. When we measured the weight and specific volume of the muffins containing Bokbunja powder, the specific volume decreased when the amount of Bokbunja powder increased (p<0.001). The moisture and pH levels of the muffins not containing Bokbunja powder were 17.04% and pH 8.59, respectively. As the volume of Bokbunja powder increased, the moisture level of Bokbunja muffin increased while the pH decreased, and there was a significant difference (p<0.001). As a result of measuring the colors of muffins, the brightness of the muffins containing Bokbunja powder decreased, and the muffins showed decreased yellowness index and increased redness. In measuring the texture of Bokbunja muffins, hardness decreased as the volume of Bokbunja power increased (p<0.001). Further, springness of the muffins decreased as the volume of Bokbunja powder increased, and there was a significant difference (p<0.001). The chewiness of the muffins not containing Bokbunja powder was higher than any other muffin sample, and there was a significant difference between the samples (p<0.001). Further, the cohesiveness of the decreased as the volume of Bokbunja powder increased (p<0.001). Bokbunja muffins showed a lower gumminess index than those not containing Bokbunja powder (p< 0.05). When the sensual qualities of the muffins were measured, the color, flavor, taste, and softness of all of the samples showed significant differences (p<0.001), and the muffins containing 8% Bokbunja powder showed the highest sensual quality indexes. When the general preference level for the muffins was measured, the muffins containing 8% Bokbunja powder showed the highest index, 7.03${\pm}$0.96. Based on this result, the ideal volume of Bokbunja powder when making muffins is 8%.

• Advances in nano research
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• 제9권4호
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• pp.251-261
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• 2020

In this article, vibration attributes of single walled carbon nanotubes based on Galerkin's method have been investigated. The influence of power law index subjected to different end supports has been overtly examined. Application of the Hamilton's variational principal leads to the formation of partial differential equations. The effects of different physical and material parameters on the fundamental frequencies are investigated for armchair and zigzag carbon nanotubes with clamped-clamped, simply supported and clamped-free boundary conditions. By using volume fraction for power law index, the fundamental natural frequency spectra for two forms of Single-Walled Carbon Nanotubes (SWCNTs) are calculated. The influence of frequencies against length-to-diameter ratios with varying power law index are investigated in detail for these tubes. MATLAB software package has been utilized for extracting tube frequency spectra. The obtained results are confirmed by comparing with available literature.