• Journal of the Korea Convergence Society
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• v.8 no.10
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• pp.215-223
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• 2017

This article has tried to analyse the effect of the corporate earning return tax empirically through analysis on the impact of previous internal reservation on the dividends rate of the current year. In addition to this, this article has tried to the effectiveness of government policies with leverage ratio as a moderating variable. Moreover, DRF and GBM model were used to see the effect again. As a result of the actual proof analysis, OCF, ROE, FOR have a significance level of 99% in model1, model2, model3. However, ADV and MSE has appeared not to be meaningful in all models. In the result of DRF and GBM model for convergence was higher than GBM in depth and leaves. However, when it comes to a model explaining capability, GBM high than DRF. The further study will be required to examine the effect of government policy by time series analysis in the period of enforcement of the reflux tax, from 2015 to 2017.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.393-400
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• 2020

Unlike conventional radiographic examinations, angiointerventional procedures have a high risk of radiation exposure to patients or operators due to prolonged radiation exposure time. This study was undertaken to examine effects of reducing the radiation risk by applying dose reduction fiber (DRF) shielding cloth during angiography. To investigate the properties of DRF shielding cloth, we measured the scattered radiation below and above a human phantom using a glass dosimeter, at site distances 10 cm away from the irradiated field. The results obtained reveal a 15 ~ 31% reduction of scattered radiation in the irradiation field, and 53 ~ 70% reduced radiation measured after phantom transmission. Taken together, our data indicate that application of DRF shielding cloth for radiation reduction at non-procedural sites during interventional procedure results in reduction of scattered doses to patients and operators, without affecting the medical examinations. We propose the use of DRF shielding during angiointerventional procedures, in order to reduce the risk of radiation exposure of patients and operators.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.263-268
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• 2004

Using the Monte Carlo simulation, a study on the lion-proportionality of the prototype phoswich detector with $2'{\times}2'$ CSI(Tl) and plastic scintillator, which was made by KAERI, has been carried. The defector response functions (DRFs) calculated by simulations were compared with the experimental measurement on the $^{137}Cs\;and\;^{60}Co$. To precisely simulate the DRF for the phoswich, the CSI(Tl) non-proportionality was calculated using the electron response and the simplified electron cascade sequence for treating the photoelectric absorption event. The resulting DRFs of $^{137}Cs\;and\;^{60}Co$ sources obtained by simulations were compared with experiments for verification. For $^{137}Cs$, gamma-ray responses simulated by MCNP5 are generally good agreement with the measured ones. But the DRF of $^{60}Co$ does not match well with the results of experiment in the energy region below second peak due to the coincidence effect of two gamma-rays (1.17 MeV and 1.33 MeV). Through the analysis of the non-proportionality of CsI(Tl) in the prototype phoswich, the improved DRFs considering non-proportionality were produced and the simulation results were verified using the experimental measurements. However, to more precisely reproduce the DRF for the phoswich, further studies in relation to the electron channeling effect and the Doppler broadening effect of a scintillator are still needed as well as considering that effect of the transfer contribution.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.79-86
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• 2008

In Korea, most of the drinking water treatment relied upon the availability of the surface water, of which the raw water quality varied significantly by season and location. Therefore, the comparison of two operation modes (Pressurized type and Submerged type membrane system) must be estimated before the long-term establishment of two systems. In this study, two pilot-scale microfiltration systems with the capacity of $50m^3/day$ were installed and operated in two different modes, and the applicability of the system was determined based on the results such as the TMP (Trans-Membrane Pressure) and flux. For quantitatively comparing the two systems, a new concept, DRF (Differential Resistance Fraction) was introduced. The accumulated sum of the permeate after each cycle of chemical cleaning was also used as a tool for the system comparison.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.759-764
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• 2007

To investigate the effect of soaking and particle sizes on the properties of rice flour and gluten-free rice bread, wet-milled (WRF, dried at $20^{\circ}C$) and dry-milled rice flours (DRF) were passed through sieves (45 or 100 mesh). Soaking of the rice grains affected the particle size distribution of flour passed through the same size screen. The L and b values of WRF were higher than those of DRF and were not changed with decreasing particle sizes, but DRF increased L and decreased b values. The initial pasting temperatures and setback viscosities of both flours decreased with decreasing particle sizes. The swelling powers at $100^{\circ}C$ increased with decreasing particle sizes in DRF, but maintained in WRF. Starch granules were observed on the surface of flour particles in WRF. The apparent viscosity of WRF paste exhibited 3-5 times higher than that of DRF. Thus, wet milled rice flour with smaller particle sizes (${\phi}<150\;{\mu}m$) showed better properties for making gluten-free rice bread.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.85-88
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• 2009

In this paper, we propose a DRF-based object detection method using the object adaptive patch in the satellite imagery. It is a Discriminative Random Fields (DRF) based work, so the detection is done by labeling to the possible patches in the image. For the feature information of each patch, we use the multi-scale and object adaptive patch and its texton histogram, instead of using the single scale and fixed grid patch. So, we can include contextual layout of texture information around the object. To make object adaptive patch, we use "superpixel lattice" scheme. As a result, each group of labeled patches represents the object or object's presence region. In the experiment, we compare the detection result with a fixed grid scheme and shows our result is more close to the object shape.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.4
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• pp.1871-1876
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• 2013

In this study, we developed and characterized the shielding properties of dose reduction fiber (DRF, Buffalo Co.) sheet during brain and chest CT examinations. The DRF sheet was composed of $1{\sim}500{\mu}m$ oxide Bismuth ($Bi_2O_3$) and 5 ~ 50 nm nano-barium sulfate ($BaSO_4$). Phantom and clinical studies were performed for characterization of the DRF shielding properties. In clinical study, we measured doses of eye, chest, abdomen and reproductive system of 60 patients in 3 hospitals during brain and chest CT examinations. We could determined the shielding effect of the DRF by comparing the doses when we used the DRF sheet or not. When we used the sheet during CT examination, the scattered dose were reduced about 20~50%. So, we suggest that the fiber should be used in radiological examinations for reducing patients doses.

• The Journal of Korean Medicine
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• v.30 no.5
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• pp.102-114
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• 2009

Objectives: HMCO5 is an extract obtained from 8 different herbal mixtures. We undertook a safety evaluation of HMCO5 for a dose range finding (DRF) toxicity test in specific pathogen free (SPF) Sprague-Dawley (SD) male and female rats. Methods: The male and female rats were divided into 4 groups, respectively; G(0), treated with distilled water: G(1), treated with 222 mg/kg HMC05: G(2), treated with 667 mg/kg HMC05, and G(3), treated with 2,000 mg/kg HMC05; HMC05 was administered orally for 4 weeks. The safety evaluation examined clinical signs, mortality, body weight, food consumption, water consumption, ophthalmic findings, urinalysis, hematological values, absolute & relative organ weights, and necropsy findings during the tests. Results: There were no changes in clinical signs, mortality, body weight, food consumption, water consumption, and ophthalmic findings examined during the test periods. In serum biochemical values, triglyceride was increased in male group G(3) and Na$^+$ decreased significantly in male groups G(2), G(3) and G(4). In male group G(4), spleen weight decreased relatively and increases of absolute & relative left ovary weights were found. In addition, an adhesion of liver to diaphragm was found in male group G(2). However, we could not find any dose-interrelationships in these changes. Conclusions: These results indicate that HMC05 extract did not show any toxicity in the DRF toxicity study. Therefore, it suggests that establishment of 1,000, 333 and 111 mg/kg dosages are moderate in a repeated dose 26-week oral toxicity study of HMC05.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.2
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• pp.61-72
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• 2018

Objectives The purpose of this experiment is to evaluate 4 weeks DRF (Dose Rate Finding) and single oral dose toxicity of ChondroT in rats. Methods In 4-week DRF, male and female Sprague-Dawely rats were treated with ChondroT at oral dose of 0, 500, 1000, and 2000 mg/kg. clinical signs, body weight, food consumption, necropsy findings, organ weight, hematological and blood-chemical parameters, and histological findings were monitored for 4 weeks. Also, after single oral administration of ChondroT, mortality, clinical signs, body weight, and necropsy findings were minitored for 2 weeks. Results In 4-week DRF and single dose oral toxicity study of ChondroT in sprague-Dawley rats, ChondroT did not exhibit any toxicity under the study conditions employed. Conclusions The results suggested a no-observed adverse effects level (NOAEL) was over 2,000 mg/kg/day in SD rats after oral administration, this study could be used as basic study of the repeated dose 13-week oral toxicity study of ChondroT.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.303-309
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• 2004

Many system devices for fluoroscopic and general X-ray studies in diagnostic radiographic system have been being changed from analog mode to digital mode. In addition, among diagnostic imaging and radiologic examinations, fluoroscopic studies that requires functional diagnosis is being widely used. The video recording method of fluoroscopic studies has been useful in functional image diagnosis and dynamic image observation, but the utility of its image quality is being reduced because of limitation in setting play segments of the video player, inconvenience of play, difficulties in preserving reproduced images, the change of image quality, etc. In order to complement these shortages, it is necessary to facilitate access to patient diagnosis information such as storing, editing and sharing functional diagnosis images in response to the trend of the digitalization of digital radiographic & fluoroscopic system(DRF). Thus this study designed and implemented a device of storing functional dynamic images real time using a computer rather than existing video recording, aiming at contribution to functional image diagnosis.