• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.773-787
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• 2020

In the injection molding process, the controlling stability of products quality is a very important factor in terms of productivity. Even when the optimum process conditions for the desired product quality are applied, uncontrollable external factors such as ambient temperature and humidity cause inevitable changes in the state of the melt resin, mold temperature. etc. Therefore, it is very difficult to maintain prodcut quality. In this study, a system that learns the correlation between process variables and product weight through artificial neural networks and predicts process conditions for the target weight was established. Then, when a disturbance occurs in the injection molding process and fluctuations in the weight of the product occur, the stability control of the product quality was performed by ANN predicting a new process condition for the change of weight. In order to artificially generate disturbance in the injection molding process, controllable factors were selected and changed among factors not learned in the ANN model. Initially, injection molding was performed with a polypropylene having a melt flow index of 10 g/10min, and then the resin was replaced with a polypropylene having a melt floiw index of 33 g/10min to apply disturbance. As a result, when the disturbance occurred, the deviation of the weight was -0.57 g, resulting in an error of -1.37%. Using the control method proposed in the study, through a total of 11 control processes, 41.57 g with an error of 0.00% in the range of 0.5% deviation of the target weight was measured, and the weight was stably maintained with 0.15±0.07% error afterwards.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.149-156
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• 2011

Phenological variables derived from remote sensing are useful in determining the seasonal cycles of ecosystems in a changing climate. Satellite remote sensing imagery is useful for the spatial continuous monitoring of vegetation phenology across broad regions; however, its applications are substantially constrained by atmospheric disturbances such as clouds, dusts, and aerosols. By way of contrast, a tower-based ground remote sensing approach at the canopy level can provide continuous information on canopy phenology at finer spatial and temporal scales, regardless of atmospheric conditions. In this study, a tower-based ground remote sensing system, called the "Phenological Eyes Network (PEN)", which was installed at the Gwangneung Deciduous KoFlux (GDK) flux tower site in Korea was introduced, and daily phenological progressions at the canopy level were assessed using ratios of red, green, and blue (RGB) spectral reflectances obtained by the PEN system. The PEN system at the GDK site consists of an automatic-capturing digital fisheye camera and a hemi-spherical spectroradiometer, and monitors stand canopy phenology on an hourly basis. RGB data analyses conducted between late March and early December in 2009 revealed that the 2G_RB (i.e., 2G - R - B) index was lower than the G/R (i.e., G divided by R) index during the off-growing season, owing to the effects of surface reflectance, including soil and snow effects. The results of comparisons between the daily PEN-obtained RGB ratios and daily moderate-resolution imaging spectroradiometer (MODIS)-driven vegetation indices demonstrate that ground remote sensing data, including the PEN data, can help to improve cloud-contaminated satellite remote sensing imagery.

• Korean Journal of Acupuncture
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• v.28 no.3
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• pp.63-71
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• 2011

Objectives : The aim of this study is to develop the system and evaluate the optical analytical technique that reflects acupoint pigmentation and extravasated blood by cupping. Methods : We designed the system able to express XYZ coordinate on local skin color. To evaluate measurement-accuracy, we compared with 24 Color Checker Chart by standardized Commission Internationale de l'Eclairage. After confirming the performance of system, we experimented with cupping which was 80 kPa negative pressure for 1 minute on left/right BL13. The X, Y and Z values were converted to R, G and B, $L^*$, $a^*$ and $b^*$, Erythema Index (E.I.), and Melanin Index (M.I). We compared and analyzed two cases on before/after cupping. Results : The R, G and B values which were converted by X, Y and Z values had high linearity as a high level of R-square (R: 0.969, G: 0.996, and B: 0.992). Moreover, we confirmed that it was possible to quantitatively analyzed the change in skin color by cupping using R, G, B, $L^*$, $a^*$, $b^*$, E.I., and M.I. Conclusions : Therefore, we proposed the new analytical technique for objectifying the oriental medical diagnostic method using cupping and optical sensing technique.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.635-641
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• 2012

In Korea, slurry composted and biofiltered (SCB) liquid fertilizer is produced through the composting and biofiltering of animal waste. An appropriate guidelines involving proper treatment of SCB liquid fertilizer on turfgrass should be considered. An experiment was conducted to determine the optimum application amount, timing, and frequency of SCB liquid fertilizer for Zoysia japonica 'Millock'. The SCB liquid fertilizer was applied in low, medium, and high amount (N at 15, 25, and 40 $g{\cdot}m^{-2}$ per year in 2010, and 10, 20, and 40 $g{\cdot}m^{-2}$ per year in 2011, respectively) and treated during the growing season or dormancy period. During the growing season, SCB liquid fertilizer was applied twice or four times. The greatest improvement in turf quality for both years was in SCB plots applied four times with N at 40 $g{\cdot}m^{-2}$ per year during the growing season (SH4). This treatment exhibited turf color retention in the fall, and enhanced clipping yield during the growing and fall seasons. SCB plots with four times during the growing season (SL4, SM4, and SH4) exhibited higher shoot density relative to the same amount of other SCB treatments. Plots treated during the dormancy period also showed a high turf color index during the next growing season in 2011. The results indicate that SCB with high amount up to N at 40 $g{\cdot}m^{-2}$ per year applied four times during the growing season and dormant application produced high turf quality and growth, and could be recommended as an optimum application guide.

• Nutrition Research and Practice
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• v.7 no.2
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• pp.77-81
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• 2013

The hypothesis of this study was that greater sugar consumption at breakfast promotes a stronger sensation of hunger and a later increase in energy consumption. The objective was to assess the relation between sugar consumption in a meal and the subsequent sensations of hunger and ad libitum food consumption. Sixteen women consumed a breakfast accompanied by 2 drinks sweetened ad libitum with sugar. After 3 h, a lunch was offered to evaluate ad libitum food consumption. During the period from breakfast to lunch, hunger sensations were evaluated at 30 min intervals. Women were divided according to the median amount of sugar used to sweeten the breakfast drinks (20 g). The group who consumed sugar above the median showed a greater hunger sensation in the preprandial period, and a greater ad libitum intake at lunch ($390{\pm}130g{\times}256{\pm}67g$, P = 0.002), compared to the group who had a lower sugar consumption. The amount of sugar consumed at breakfast was correlated positively with the sensation of preprandial hunger and food intake at lunch. We concluded that foods with a high glycemic index can modulate the appetite within a short period of time.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.182-188
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• 1999

Production of extracellular polysaccharide by Monilinia fructigena in B-I medium containing cereals was higher than that in glucose medium. Productivities in B-I medium and glucose medium were 0.7g/l nd 0.2-03g/l respectively. The maximum content of polysaccharide occurred at the rising point from the lowest pH of culture. As the apparent viscosity of the polysaccharide solution increased, the flow Index (m) decreased, and the consistency Index (Kc) also increased. The polysaccharide solution was a typical pseudoplastic fluid. The mycelium was separated from the culture solution by $300\mu m$ mesh-filter and the polysaccharide was precipitated by adding 50% of ethanol (v/v). The amount of the polysaccharide removed from the filtrated solution was 0.45 g/l and the amount adhered to the mycelium was 0.25g/l. In experiments for investigating growth enhancement of rotifer (Brachionus plicatilis) by the polysaccharide, the dose of the polysaccharide was 1mg per 10,000 organisms of rotifer. Maximum specific growth rate of rotifer with feed consisting of sea Chlorella sp. and the polysaccharide was 1.095/day in the batch culture for 10 days. A semi-continuous culture was done for 30 days, the biomass of rotifer could be harvested twice. Maximum specific growth rate with sea Chlorella sp. and the polysaccharide was 0.734/day before the first harvest, and 1.685/day before the second harvest. Productivity was 38 $cells/ml\; \cdot\; day$ with sea Chlorella sp. and the polysaccharide.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.233-239
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• 2009

The effects of guar gum (GG) and xanthan gum (XG) at different concentrations (0, 0.2, 0.4, and 0.6% w/w) on the rheological properties of Korean waxy rice starch (WRS) pastes were evaluated under both steady and dynamic shear conditions. The flow properties of WRS-gum mixtures were determined from the rheological parameters of the power law model. The addition of GG and XG to WRS resulted in an increase in the apparent viscosity ($\eta_{a,100}$) and consistency index (K) values obtained from power law model. The flow behavior index (n) values of the WRS-XG mixtures decreased with an increase in gum concentration while there was only a marginal difference between n values for the WRS-GG mixtures. Dynamic moduli (G', G", and $\eta^*$) values in the WRS-gum mixture systems also increased with an increase in gum concentration. WRS-XG mixtures had higher dynamic moduli and lower tan $\delta$ (ratio of G"/G') values than WRS-GG mixtures, indicating that the higher dynamic rheological properties of WRS-XG can be attributed to an increase in the viscoelasticity of the continuous phase in the starch-gum mixture systems, which was due to the higher viscoleastic properties of XG compared to GG. The dynamic ($\eta^*$) and steady shear ($\eta_a$) viscosities of the WRS-XG paste at a 0.2% gum concentration followed the Cox-Merz superposition rule.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.388-394
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• 2014

Inorganic-organic hybrid coating solutions were synthesized using titania sol from titanium isopropoxide (TTIP) as an inorganic component and mixture of two or three types of silane coupling agents, such as methacryloxypropyl trimethoxysilane (MPTMS), aminopropyl triethoxysilane (APS), glycidoxypropyl trimethoxysilane (GPTMS) and vinyltriethoxysilane (VTES) as an organic component. The hard coating films were obtained by spin-coating on the polycarbonate sheets and curing the inorganic-organic hybrid coating solutions. The coating films made from the mixture of two types of silane coupling agents showed poor pencil hardness and adhesion, while those from the mixture of three types of silane coupling agents exhibited an improved pencil hardness of 2H~4H and adhesion of 5B. The refractive indexes of coating films were increased from 1.56 to 1.63 at 550 nm by increasing the content of titania sols from 20 to 30 g.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1025-1029
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• 2012

Objective: To determine the killing effects on extracorporeal HepG2 cells under different temperatures, pressures of permeability and lengths of treatment time. Method: According to different temperatures, pressures of permeability and lengths of treating time, extracorporeal HepG2 cells of human hepatoma cell-line were grouped to 80 groups. Cell index (CI) as the measurement of killing effect were calculated by monotetrazolium (MTT) methods, i.e., CI =1- (the OD value in treated group - the OD value in blank control group) / (mean of untreated control group - mean of blank control group). According to the factorial design, data were fed into SPSS 10.0 and analyzed by three-way ANOVA (analysis of variance). Result: Temperature, pressure of permeability and length of treating time all had effects on the CI (cell index) level. Length of treating time was the most influential factor of the three. Additionally, any two of them all had statistically significant interactive effects on the CI level. When treated for 5-30 min, destilled water at $46^{\circ}C$ stably generated the highest CI. Conclusion: The "$46^{\circ}C$-destilled water-60 min" was considered as the optimal combination of conditions which lead to highest CI. We suggest exerting celiac lavage for 15 min with stilled water at $40^{\circ}C-43^{\circ}C$ in surgical practice as a hyperthermia treatment to achieve ideal killing effects on free cancer cells, which is feasible, practical, and clinically effective.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.28 no.2
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• pp.84-88
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• 2017

Background and Objectives : The purpose of this study was to compare the usefulness of Cepstral peak prominence (CPP) with parameter of Multiple Dimensional Voice Program (MDVP) in evaluating unilateral vocal fold paraylsis patients with subjective voice impairment. Materials and Methods : From July 2014 to August 2016, 37 patients with unilateral vocal fold paralysis who had been diagnosed with unilateral vocal fold paralysis and had received two or more voice tests before and after the diagnosis were evaluated for maximum phonation time (MPT), MDVP and CPP. Respectively. Voice tests were performed with short vowel /a/ and paragraph reading. Results : The CPP-a (CPP with vowel /a/) and CPP-s (CPP with paragraph reading) of the Cepstrum were statistically negatively correlated with G, R, B, and A before the voice therapy. Jitter, Shimmer, and NHR of MDVP were positively correlated with G, R, B. Jitter, Shimmer, and NHR of the MDVP were significantly correlated with the Cepstrum index. G, B, A and CPP-a and CPP-s showed a statistically significant negative correlation and a somewhat higher correlation coefficient between 0.5 and 0.78. On the other hand, in MDVP index, there was a positive correlation with G and B only with Jitter of 0.4. Conclusion : CPP can be an important evaluation tool in the evaluation of speech in the unilateral vocal cord paralysis when speech energy changes or the cycle is not constant during speech.