• Kidney Research and Clinical Practice
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• v.37 no.4
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• pp.393-403
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• 2018

Background: This study compared nutritional parameters in hemodialysis (HD) subjects and controls using bioimpedance analysis (BIA) and investigated how BIA components changed before and after HD. Methods: This cross-sectional study included 147 subjects on maintenance HD from two hospitals and 298 propensity score-matched controls from one healthcare center. BIA was performed pre- and post-HD at mid-week dialysis sessions. Results: Extracellular water/total body water (ECW/TBW) and waist-hip ratio were higher in the HD patients; the other variables were higher in the control group. The cardiothoracic ratio correlated best with overhydration (r = 0.425, P < 0.01) in HD subjects. Blood pressure, hemoglobin, creatinine, and uric acid positively correlated with the lean tissue index in controls; however, most of these nutritional markers did not show significant correlations in HD subjects. Normal hydrated weight was predicted to be higher in the pre-HD than post-HD measurements. Predicted ultrafiltration (UF) volume difference based on pre- and post-HD ECW/TBW and measured UF volume difference showed a close correlation ($r^2=0.924$, P < 0.01). Remarkably, the leg phase angle increased in the post-HD period. Conclusion: The estimated normal hydrated weight using ECW/TBW can be a good marker for determining dry weight. HD subjects had higher ECW/TBW but most nutritional indices were inferior to those of controls. It was possible to predict UF volume differences using BIA, but the post-HD increase in leg phase angle, a nutritional marker, must be interpreted with caution.

• Food Engineering Progress
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• v.15 no.3
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• pp.269-275
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• 2011

The baking performance of yacon powder as a value-added food ingredient was investigated in a model system of sponge cakes. Yacon powder was incorporated into cake batter at 5 levels (0, 10, 20, and 30%, w/w) by replacing equivalent amount of wheat flour. The specific gravity of batter increased significantly while pH decreased significantly with the increase in yacon powder content (p < 0.05). The specific volume and moisture content of sponge cakes decreased while baking loss increased (p < 0.05). Volume of the cakes decreased with higher amount of yacon powder in the formulation as indicated by the decrease in the volume index. The symmetry index was not affected by the amount of yacon powder in the formulation (p > 0.05). Sponge cakes became darker and firmer with increase in yacon powder content (p < 0.05). Finally, the consumer acceptance test indicated that incorporation of yacon powder up to 20% in the formulation of sponge cakes did not significantly influence the consumers' overall acceptability.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.36-46
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• 2019

If stock market is efficient, any well-devised trading rule can't consistently outperform the average stock market returns. This study aims to verify whether the strategy based on bid-ask volume information can beat the stock market. I suggested a day trading strategy using order imbalance indicator and empirically analyzed its profitability with the KOSPI 200 index futures data from 2001 to 2018. Entry rules are as follows: If BSI is over 50%, enter buy order, otherwise enter sell order, assuming that stock price rises after BSI is over 50% and stock price falls after BSI is less than 50%. The empirical results showed that the suggested trading strategy generated very high trading profit, that is, its annual return runs to minimum 71% per annum even after the transaction costs. The profit was generated consistently during 18 years. This study also improved the suggested trading strategy applying the genetic algorithm, which may help the market practitioners who trade the KOSPI 200 index futures.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1414-1420
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• 2022

High dose rate (HDR) brachytherapy treatment planning usually involves optimization methods to deliver uniform dose to the target volume and minimize dose to the healthy tissues. Four optimizations were used to evaluate the high-risk clinical target volume (HRCTV) coverage and organ at risk (OAR). Dose-volume histogram (DVH) and dosimetric parameters were analyzed and evaluated. Better coverage was achieved with PGO (mean CI = 0.95), but there were no significant mean CI differences than GrO (p = 0.03322). Mean EQD₂ doses to HRCTV (D₉₀) were also superior for PGO with no significant mean EQD₂ doses than GrO (p = 0.9410). The mean EQD₂ doses to bladder, rectum, and sigmoid were significantly higher for NO plan than PO, GrO, and PGO. PO significantly reduced the mean EQD₂ doses to bladder, rectum, and sigmoid but compromising the conformity index to HRCTV. PGO was superior in conformity index (CI) and mean EQD₂ doses to HRCTV compared with the GrO plan but not statistically significant. The mean EQD₂ doses to the rectum by PGO plan slightly exceeded the limit from ABS recommendation (mean EQD₂ dose = 78.08 Gy EQD₂). However, PGO can shorten the treatment planning process without compromising the CI and keeping the OARs dose below the tolerance limit.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.1
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• pp.28-41
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• 2023

Objectives: This study was aimed to evaluate the hemodynamic feasibility using pulse parameters as a way to establish safe dose guidelines for herbal prescription containing Ephedra herb (Ephedra intermedia Schrenk & C.A.Mey) on weight loss, and to provide a foundation for developing evidence-based guidelines for clinical use. Methods: Forty-two volunteers were recruited to participate in a study examining the changes in pulse wave characteristics following the ingestion of Gambi-hwan, a herbal prescription containing ephedra, over a period of 4 weeks, and pulse wave measurements were taken before and after the administration. Pulse wave parameters were measured in this study using a 3-dimensional radial pulse tonometry device (DMP-Lifeplus). In addition, questionnaire, blood pressure, temperature, and body composition were also measured as secondary measures. Results: Fifteen minutes after administration of Gambi-hwan, the non-adverse event group (non-AE) exhibited a statistically significant increase in several power and pressure-related parameters, including h1, h5, systolic area, pulse area, and pulse width, while the AE group showed a trend of decreasing stroke volume and increasing Radial Augmentation Index (RAI), w, and w/t. After 4 weeks of administration, both groups exhibited significant changes in pulse rate, w/t, RAI, t3/t, stroke volume (SV), and stroke volume Index (SVI). Notably, there are significant differences between AE group and non-AE group in w/t, SV, and SVI. Conclusions: These findings suggest that pulse parameters may be a useful way to establish safe dosing guidelines for weight loss herbal prescription containing ephedra. Further research is needed to confirm these results and to develop evidence-based guidelines for clinical use.

• Korean Journal of Materials Research
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• v.20 no.7
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• pp.370-373
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• 2010

In fabricating plasma display panels, the photolithographic process is used to form patterns of barrier ribs with high accuracy and high aspect ratio. It is important in the photolithographic process to control the refractive index of the photosensitive paste. The composition of this paste for photolithography is based on the $B_2O_3-SiO_2-Al_2O_3$ glass system, including additives of alkali oxides and rare earth oxides. In this work, we investigated the density, structure and refractive index of glasses based on the $B_2O_3-SiO_2-Al_2O_3$ system with the addition of $Li_2O$, $K_2O$, $Na_2O$, CaO, SrO, and MgO. The refractive index of the glasses containing K2O, Na2O and CaO was similar to that of the [BO3] fraction while that of the SrO, MgO and Li2O containing glasses were not correlated with the coordination fraction. The coordination number of the boron atoms was measured by MAS NMR. The refractive index increased with a decrease of molar volume due to the increase in the number of non-bridging oxygen atoms and the polarizability. The lowest refractive index (1.485) in this study was that of the $B_2O_3-SiO_2-Al_2O_3-K_2O$ glass system due to the larger ionic radius of $K^+$. Based on our results, it has been determined that the refractive index of the $B_2O_3-SiO_2-Al_2O_3$ system should be controlled by the addition of alkali oxides and alkali earth oxides for proper formation of the photosensitive paste.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.1
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• pp.31-37
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• 2012

Purpose: This study evaluated the usefulness of Helmet bolus device using Bolx-II, paraffin wax, solid thermoplastic material in total scalp irradiation. Materials and Methods: Using Rando phantom, we applied Bolx-II (Action Products, USA), paraffin wax (Densply, USA), solid thermoplastic material (Med-Tec, USA) on the whole scalp to make helmet bolus device. Computed tomography (GE, Ultra Light Speed16) images were acquired at 5 mm thickness. Then, we set up the optimum treatment plan and analyzed the variation in density of each bolus (Philips, Pinnacle). To evaluate the dose distribution, Dose-homogeneity index (DHI, $D_{90}/D_{10}$) and Conformity index (CI, $V_{95}/TV$) of Clinical Target Volume (CTV) using Dose-Volume Histogram (DVH) and $V_{20}$, $V_{30}$ of normal brain tissues. we assessed the efficiency of production process by measuring total time taken to produce. Thermoluminescent dosimeters (TLD) were used to verify the accuracy. Results: Density variation value of Bolx-II, paraffin wax, solid thermoplastic material turned out to be $0.952{\pm}0.13g/cm^3$, $0.842{\pm}0.17g/cm^3$, $0.908{\pm}0.24g/cm^3$, respectively. The DHI and CI of each helmet bolus device which used Bolx-II, paraffin wax, solid thermoplastic material were 0.89, 0.85, 0.77 and 0.86, 0.78, 0.74, respectively. The result of Bolx-II was the best. $V_{20}$ and $V_{30}$ of brain tissues were 11.50%, 10.80%, 10.07% and 7.62%, 7.40%, 7.31%, respectively. It took 30, 120, 90 minutes to produce. The measured TLD results were within ${\pm}7%$ of the planned values. Conclusion: The application of helmet bolus which used Bolx-II during total scalp irradiation not only improves homogeneity and conformity of Clinical Target Volume but also takes short time and the production method is simple. Thus, the helmet bolus which used Bolx-II is considered to be useful for the clinical trials.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.622-629
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• 2022

The study aim was to derive a stem taper equation for Phyllostachys pubescens, a type of bamboo in South Korea, and to develop a stem volume table. To derive the stem taper equation, three stem taper models (Max & Burkhart, Kozak, and Lee) were used. Since bamboo stalks are hollow because of its woody characteristics, the outer and inner diameters of the tree were calculated, and connecting them enabled estimating the tree curves. The results of the three equations for estimating the outer and inner diameters led to selection of the Kozak model for determining the optimal stem taper because it had the highest fitness index and lowest error and bias. We used the Kozak model to estimate the diameter of Phyllostachys pubescens by stem height, which proved optimal, and drew the stem curve. After checking the residual degree in the stem taper equation, all residuals were distributed around "0", which proved the suitability of the equation. To calculate the stem volume of Phyllostachys pubescens, a rotating cube was created by rotating the stem curve with the outer diameter at 360°, and the volume was calculated by applying Smalian's method. The volume of Phyllostachys pubescens was calculated by deducting the inner diameter calculated volume from the outer diameter calculated volume. The volume of Phyllostachys pubescens was only 20~30% of the volume of Larix kaempferi, which is a general species. However, considering the current trees/ha of Phyllostachys pubescens and the amount of bamboo shoots generated every year, the individual tree volume was predicted to be small, but the volume/ha was not very different or perhaps more. The significance of this study is the stem taper equation and stem volume table for Phyllostachys pubescens developed for the first time in South Korea. The results are expected to be used as basic data for bamboo trading that is in increasing public and industrial demand and carbon absorption estimation.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.11-25
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• 2002

Objectives: This study was undertaken to investigate the effects of Yijin-tang and GamiYijin-tang on the gastrointestinal functions of rats Methods: Sprague-Dawley rats were used as experimental animals, and were administered Yijin-tang (Sample I group, 47.5 mg/ml) and GamiYijin-tang(Sample II group, 38.37 mg/ml, Sample ill group, 85.3 mg/ml) water extract once a day. Changes of gastric juice volume and intestinal mobility index were measured. The effects on colitis induced by dextran sulfate sodium in the rats were also observed. Results: 1. Gastric juice volume was decreased significantly in the sample I group (P<0.05) compared to the control group; there was not significant effect in the sample II and sample III groups. 2. The moving distance of carbon bolus was increased significantly in the sample n (p<0.05) and sample II (p<0.05) groups compared to the control group; there was not significant effect in the sample I group. 3. The intestinal mobility index was increased significantly only in the sample II group (P<0.05) compared to the control group. 4. The feces consistency was increased significantly on the 3rd and 5th day of the sample I group (P<0.05), on 3rd, 4th, and 5th day of the sample II (p<0.05) and the sample III (p<0.05) groups compared to the control group. 5. The feces property index was increased significantly only on the 5th day of the sample III group (p<0.05) compared to the control group. 6. The number of WBC and RBC, levels of hemoglobin and hematocrit were not changed in all sample groups compared to the control group. 7. The number of the type B Goblet cells were increased significantly in the sample II (p<0.05) and the sample III (P<0.05) groups, but the number of the type C Goblet cells were decreased significantly only in the sample ill group (P<0.05) compared to the control group. Conclusions: According to the above results, GamiYijin-tang compared to the Yijin-tang were decreased hight significantly in gastrointestinal mucose and histological antidiarrheal function with protection of the goblet cell more excellently were observed.

• Journal of KIISE:Software and Applications
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• v.30 no.7_8
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• pp.610-617
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• 2003

Similarity matching in video database is of growing importance in many new applications such as video clustering and digital video libraries. In order to provide efficient access to relevant data in large databases, there have been many research efforts in video indexing with diverse spatial and temporal features. however, most of the previous works relied on sequential matching methods or memory-based inverted file techniques, thus making them unsuitable for a large volume of video databases. In order to resolve this problem, this paper proposes an effective and scalable indexing technique using a trie, originally proposed for string matching, as an index structure. For building an index, we convert each frame into a symbol sequence using a window order heuristic and build a disk-resident trie from a set of symbol sequences. For query processing, we perform a depth-first search on the trie and execute a temporal segmentation. To verify the superiority of our approach, we perform several experiments with real and synthetic data sets. The results reveal that our approach consistently outperforms the sequential scan method, and the performance gain is maintained even with a large volume of video databases.