• Radiation Oncology Journal
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• v.38 no.2
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• pp.138-147
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• 2020

Purpose: To evaluate the dosimetric variations in patients of head and neck cancer treated with definitive or adjuvant radiotherapy using optimized non-coplanar (ncVMAT) beams with coplanar (cVMAT) beams using volumetric arc therapy. Materials and Methods: Twenty-two patients of head and neck cancer that had received radiotherapy using VMAT in our department were retrospectively analyzed. Each of the patients was planned using coplanar and non-coplanar orientations using an optimized couch angle and fluences. We analyzed the Conformity Index (C_IRTOG), Dose Homogeneity Index (DHI), Heterogeneity Index (HI_RTOG), low dose volume, target and organs-at-risk coverage in both the plans without changing planning optimization parameters. Results: The prescription dose ranged from 60 Gy to 70 Gy. Using ncVMAT, C_IRTOG, DHI and HI_RTOG, and tumor coverage (ID_95%) had improved, low dose spillage volume in the body V_5Gy was increased and V_10Gy was reduced. Integral dose and intensity-modulated radiation therapy factor had increased in ncVMAT. In the case of non-coplanar beam arrangements, maximum dose (D_max) of right and left humeral head were reduced significantly whereas apex of the right and left lung mean dose were increased. Conclusion: The use of ncVMAT produced better target coverage and sparing of the shoulder and soft tissue of the neck as well as the critical organ compared with the cVMAT in patients of head and neck malignancy.

• Journal of IKEEE
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• v.23 no.1
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• pp.295-301
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• 2019

A heater in a portable real-time polymerase chain reaction(PCR) system is one of the important factors for controlling the PCR thermocycle precisely. Since heaters are integrated on a small-sized PCR chip for rapid heating and fabricated by semiconductor processes, the cost of producing PCR chips is high. Here, we propose to use chip resistors as an inexpensive and accurate temperature control method. The temperature distribution was simulated using one or two chip resistors on a real-time PCR chip and the PCR chip with uniform temperature distribution was fabricated. The temperature rise and fall rates were $18^{\circ}C/s$ and $3^{\circ}C/s$, respectively.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.5
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• pp.223-229
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• 2023

This Paper propose the method that measure main system parameters for PI(proportional-integral) current control of a.c. motor adopting the vector control technique. For current control, the PI control input is could be tuning by several selective methods. Among the several methods, the method that using the main system parameters, wire resistance and inductance, are frequently used. In this study, the technique to dissect and measure these two system parameters through the results of simple feedback control. This analytic measurement method is measuring parameters step by step dissecting the results of P control using simple proportional feedback gain about the unit step or multiple step reference command. This strategy is an real time analytic measurement method that calculate current control gains of torque component and flux component both for vector control of A.C. motor without introducing the further measurement circuits and complex measuring algorithms.

• Journal of the Korean Dietetic Association
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• v.30 no.3
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• pp.192-203
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• 2024

The digital environment has become an integral part of human lives today. This study aimed to investigate Mukbang watching status and its association with eating behaviors, eating habits, and the nutritional status of children. We conducted a survey of the actual status of Mukbang watching, and nutrition quotient of children (NQ-C) among 222 students in elementary schools in Daejeon. The prevalence of viewing Mukbang content was 68.9%, the most common frequency of viewing was 1~2 times per month (36.5%), and the duration of watching a single episode was less than 10 minutes (54.9%). Overall, 31.4% of students responded that they ate while watching a Mukbang and, 66.0% said they felt hungry after watching a Mukbang. YouTube (82.4%) was the most common source of viewing Mukbang. The most common reason for watching Mukbang was because all the students found the content entertaining. The NQ-C score of all the subjects surveyed was 58.95, which is a moderate grade. The scores of NQ-C, balance, and practice factors were significantly higher in boys than in girls. In addition, the scores of NQ-C, and balance and moderation were significantly higher in Mukbang non-viewers than viewers for all subjects and more specifically boys. These results suggest that watching Mukbang is associated with poor nutritional status in elementary school children. Therefore, it is necessary to consider the Mukbang watching status when providing nutrition guidance to instill healthy eating habits in children.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.26-67
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• 2020

Synthetic Aperture Radar(SAR) is able to photograph the earth's surface regardless of weather conditions, day and night. Because of its possibility to search for hydrological factors such as soil moisture and groundwater, and its importance is gradually increasing in the field of water resources. SAR began to be mounted on satellites in the 1970s, and about 15 or more satellites were launched as of 2020, which around 10 satellites will be launched within the next 5 years. Recently, various types of SAR technologies such as enhancement of observation width and resolution, multiple polarization and multiple frequencies, and diversification of observation angles were being developed and utilized. In this paper, a brief history of the SAR system, as well as studies for estimating soil moisture and hydrological components were investigated. Up to now hydrological components that can be estimated using SAR satellites include soil moisture, subsurface groundwater discharge, precipitation, snow cover area, leaf area index(LAI), and normalized difference vegetation index(NDVI) and among them, soil moisture is being studied in 17 countries in South Korea, North America, Europe, and India by using the physical model, the IEM(Integral Equation Model) and the artificial intelligence-based ANN(Artificial Neural Network). RADARSAT-1, ENVISAT, ASAR, and ERS-1/2 were the most widely used satellite, but the operation has ended, and utilization of RADARSAT-2, Sentinel-1, and SMAP, which are currently in operation, is gradually increasing. Since Korea is developing a medium-sized satellite for water resources and water disasters equipped with C-band SAR with the goal of launching in 2025, various hydrological components estimation researches using SAR are expected to be active.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.545-553
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• 1991

To find out the basic data for the possibility of agricultural utilization for GSA (Glutamine Synthetase Activity), the effect of nitrogen on the GSA in wheat leaf discs, the variation of GSA after light treatment and the comparative activity of GS during preservation were studied. The result of this study suggested that GSA could play an important and direct regulatory role in the nitrogen assimilation by wheat. During the growth stage of wheat its integral activity was found to closely match the organic nitrogen content. GS may therefore be the rate limiting enzyme in inorganic N assimilation. Moreover, integral GSA was closely correlated with grain yield and grain nitrogen. GSA could be suitable to utilize as a parameter for super type selection and an indicator for optimum nitrogen fertilization. Throughout the experiment, the contents of NO; were increased by N fertilization so that the NO; content was not attributable to change in the level of GSA. At investigation during dark-light transition of culture, no change in the level of GSA was observed until after 8-14 hours in the light treatment. And the level of GSA in wheat leaf discs during preservation at refrigerated storage $(-20^{\circ}C)$ was stable until 12 weeks, when its leaf discs were sampled with liquid nitrogen.

• Journal of the Korea Society of Computer and Information
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• v.15 no.6
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• pp.111-120
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• 2010

Looking at the application examples related to RFID systems around the world, it is easy to find that RFID systems are introduced in various industries, such as retail and consumer goods sectors, financial and security sectors, automotive and transport sector, leisure and sports sector, logistics, and health-related fields. This is because they can get their operational efficiency and competitiveness by means of product's visibility and transparency of information through RFID systems. However, it is required that evaluation of effectiveness on introducing RFID systems should be performed to strengthen construction willingness of RFID systems before actual introduction of the RFID systems in the process. This activity affects to introduction of RFID systems in industry-wide and then, will be able to create a synergy effect such as national industrial competitiveness improvement. The purpose of this study is to offer rational method on effectiveness analysis before and after RFID based process. Accordingly, the proposed Choquet fuzzy integral-based model will be allowed rational analysis by integrating quantitative and qualitative analysis. Through the effectiveness analysis of C company's RFID based process using the proposed evaluation model, we could identify that RFID-based logistics process was more effective than existing process.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1633-1636
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• 2015

Background: The advantages of Rapid Arc plans versus Intensity modulated radiotherapy plans for Carcinoma left breast were analyzed. Materials and Methods: In this study 20 Post mastectomy carcinoma left breast patients were analyzed. Both Intensity modulated Radiotherapy and Rapid Arc plans were generated for these patients. IMRT plans with 7 beams in an arc fashion and VMAT plans with two semi arcs were made to achieve 95% dose coverage to 100% volume. The plans were evaluated using Dose volume Histograms. Results: The mean Conformity and Homogeneity index in VMAT is found to be 1.05 and 0.065 respectively whereas in IMRT it was 1.07 and 0.069. The 20% volume of Heart received a mean dose of 960cGy in VMAT and 1300cGy in IMRT. The mean dose was 1236cGy in VMAT and 1870cGy in IMRT. The ipsilateral Lung received 3395cGy to 5% volume and 1840cGy to 20% volume on an average and the mean dose was 1205cGy in VMAT, while the same were found to be 3525cGy, 2012cGy and 1435cGy respectively in IMRT. The Contralateral Lung received a mean dose of 505cGy in VMAT and 553cGy in IMRT. The mean Monitor units in VMAT were 512MU and 1170MU in IMRT. The NTID in VMAT is $108.8{\times}10^5Gycm^3$ and $110.1{\times}10^5Gycm^3$ in IMRT. Conclusions: The target coverage, homogeneity and Conformity index were better in VMAT plans. The Ipsilateral Lung and heart dose were very less in VMAT plans. The Contralateral Lung dose and the Normal Tissue Integral Dose were also lesser in VMAT plans however the difference is not very appreciable. The MU in VMAT plans is almost 50% that of the IMRT plans which results in the reduction of treatment time. On the whole VMAT proves to be a better modality for treating Ca. Left Breast Patients.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.888-901
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• 1996

Oxidations of cyclopentene and of 1-pentene with air have been studied on a V/Mo/P/Al/Ti-mixed oxide catalyst in a fixed bed integral reactor. At high levels of conversion maleic anhydride was in each case produced as the major organic product, along with minor amounts of phthalic anhydride and, only starting from 1-pentene, also of citraconic anhydride. At lower levels of conversion a total of 30 organic products have been identified, some of which may be intermediates on the way from the substrates to the three anhydrides mentioned above. Based on the dependence of selectivities of the organic products on conversion, reaction schemes for the formation of maleic anhydride, phthalic anhydride and citraconic anhydride have been proposed. Oxidation at $310^{\circ}C$ led to increasing conversions and selectivities for maleic anhydride with decreasing space velocities. The highest selectivities for maleic anhydride were obtained at conversion of ca. 100%. Oxidation at a constant space velocity of $2{\cdot}10^4h^{-1}$ led to increasing conversions with increasing temperatures in the range of $300^{\circ}C{\sim}420^{\circ}C$, while the selectivity for maleic anhydride passed through a maximum value of ca. 39% at $370^{\circ}C$ in the oxidation of cyclopentene and a maximum value of ca. 30% at $400^{\circ}C$ in the oxidation of 1-pentene.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.65-72
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• 1985

Vitamin C is known as an integral element for the formation and maintenance of intercellular supporting structures. Ascorbic acid has been used for the treatment of certain poisonings and hypovitaminosis(scurvy) but also known as a powerful reducing agent, and can kill a variety of bacteria and detoxify bacterial exotoxins including various clostridial exotoxins in vitro. For viruses, vitamin C inactivates herpes virus, vaccinia virus and influenza virus and has been used for the prevention and treatment of the common cold. Thus ascorbic acid plays an important role in antimicrobial action. Scurvy also promotes the development of tubercles in experimentally infected guinea pig and the tuberculosis patients require more vitamin C than normal persons. However there is no reports that ascorbic acid could inhibit the growh of M. tuberculosis. In this paper, antibacterial effects of ascorbic acid against M. tuberculosis were studied. The results are as follows: 1. The single use of the ascorbic acid exhibited antibacterial effect in vitro against $5{\times}10^3/ml$ of M. tuberculosis $H_{37}$ Rv at the concentration of ascorbic acid 0.625mg/ml over 3 hours exposure and 0.05mg/ml over 9 hours exposure. 2. In vivo mice administered with ascorbic acid 50mg/day for 5, 10 and 15 days respectively were protected from M. tuberculosis $2LD_{50}$, $3LD_{50}$, $4LD_{50}$ and $5LD_{50}$ given intravenously.