• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.5937-5942
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• 2012

This study used silicon that is similar to the density of the tissue of the human body to compensate for the uneven areas that are in contact with air in order to reduce susceptible artifacts. The subjects of the study were 16 normal people and the areas of the human body in which there are a lot of uneven areas with complicated structure and a lot of susceptible artifacts were formed since the surface area that comes into contact with the air is large were the areas that were chosen to be examined. A 3.0T superconducting magnetic resonance device was used as the test equipment and SPIR images that are sensitive to magnetic differences were obtained as sagittal planes on a line that extended the metatarsal and the phalanges, including the middle of the longitudinal arc and the 5 distal phalanxes. The method of analysis was to reduce the susceptibility between the tissue and the air to discover the reduction of susceptible artifacts by comparing the SNR and CNR before and after applying silicon. A statistical analysis was utilized for the sample matching T examination. The results of the study revealed that the susceptible artifacts were reduced in the images of the uneven areas that were compensated and applied with silicon. The SNR increased in significant amount in correlation from $3.91{\pm}1.33$ before application to $21.69{\pm}4.52$ after application and the CNR decreased in significant amount in correlation from $28.97{\pm}8.20$ before application to $4.88{\pm}2.14$. In conclusion, this study did not affect the voxel but it was an innovative method of improvement that compensated for the fundamental issue of the difference in susceptibility between the air and the body. The application is simple and the study has great significance in that it proposed a method to reduce susceptible artifacts in a low cost and highly efficient manner.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.2
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• pp.107-113
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• 2015

Purpose : The measurement of skin dose is very important that treatment of breast cancer. On account of the cold or hot dose as compared with prescription dose, it is necessary to analyse the skin dose occurring during the various plan of the breast cancer treatment. At our hospital, we want to apply various analyses using a diversity of dosimeters to the breast cancer treatment. Subjectss and Methods : In the study, the anthropomorphic phantom is used to find out the dose difference of the skin(draining site), scar and others occurring from the tangential treatment plan of breast cancer. We took computed tomography scan of the anthropomorphic phantom and made plans for the treatment planing using open and wedge, Field-in-Field, Dose fluence. Using these, we made a comparative analysis of the dose date points by using the Eclipse. For the dose comparison, we place the anthropomorphic phantom in the treatment room and compared the measurement results by using the TLD and MOSFET on the dose data points. Results : On the central point of treatment planing basis, the upward and downward skin dose measured by the MOSFET was the highest when the fluence was used. The skin dose of inner and outer was distinguished from the figure(5.7% ~ 10.3%) when the measurements were fulfilled by using TLD and MOSFET. The other side of breast dose was the lowest in the open beam, on the other hand, is highest in the Dose fluence plan. In the different kinds of treatment, the dose deviation of inner and outer was the highest, and so this was the same with the TLD and MOSFET measurement case. The outer deviation was highest in the TLD, and the Inner'was highest in the MOSFET. Conclusion : Skin dose in relation to the treatment plan was the highest in the planing using the fluence technique in general and it was supposed that the high dose had been caused by the movement of the MLC. There's some differences among the all the treatment planning, but the sites such as IM node occurring the lack of dose, scar, drain site are needed pay close attention. Using the treatment planning of dose fluence is good to compensate the lack of dose, but It increases the dose of the selective range rather than the overall dose. Therefore, choosing the radiotherapy technique is desirable in the lights of the age and performance of the patient.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1082-1090
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• 2009

Peak expiratory flow rate(PEF) is a very important diagnostic parameter obtained from the forced vital capacity(FVC) test. The expiratory flow rate increases during the short initial time period and may cause measurement error in PEF particularly due to non-ideal dynamic characteristic of the transducer. The present study evaluated the initial rise slope($S_r$) on the flow rate signal to compensate the transducer output data. The 26 standard signals recommended by the American Thoracic Society(ATS) were generated and flown through the velocity-type respiratory air flow transducer with simultaneously acquiring the transducer output signal. Most PEF and the corresponding output($N_{PEF}$) were well fitted into a quadratic equation with a high enough correlation coefficient of 0.9997. But only two(ATS#2 and 26) signals resulted significant deviation of $N_{PEF}$ with relative errors>10%. The relationship between the relative error in $N_{PEF}$ and $S_r$ was found to be linear, based on which $N_{PEF}$ data were compensated. As a result, the 99% confidence interval of PEF error was turned out to be approximately 2.5%, which was less than a quarter of the upper limit of 10% recommended by ATS. Therefore, the present compensation technique was proved to be very accurate, complying the international standards of ATS, which would be useful to calibrate respiratory air flow transducers.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.51-63
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• 2019

Purpose: Radiation therapy for breast cancer should consider the change in breast shape due to breathing and swelling. In this study, we evaluate the benefit of using virtual bolus for IMRT of left breast cancer. Materials and methods: 10 patients with early breast cancer who received radiation therapy after breastconserving surgery compared the VMAT and IMRT plans using the virtual bolus method and without using it. The first analysis compared the V95%, HI, CI of treatment volume, Dmean, V5, V20, V30 of ipsilateral lung, and Dmean of heart in VMAT plan made using the virtual bolus method(VMAT_VB) to the plan without using it(VMAT_NoVB) in case there is no change in the breast. In IMRT, the same method was used. The second analysis compared TCP and NTCP based on each treatment plan in case there is 1cm expansion of treatment volume. Result: If there is no change in breast, V95% in VB Plan(VMAT_VB, IMRT_VB) and NoVB Plan(VMAT_NoVB, IMRT_NoVB) is all over 99% on each treatment plan. V95% in VMAT_NoVB and VMAT_VB is 99.80±0.17% and 99.75±0.12%, V95% in IMRT_NoVB and IMRT_VB is 99.67±0.26% and 99.51±0.15%. Difference of HI, CI is within 3%. OAR dose in VB plan is a little high than NoVB plan, and did not exceed guidelines. If there is 1cm change in breast, VMAT_NoVB and IMRT_NoVB are less effective for treatment. But VMAT_VB and IMRT_VB continue similar treatment effect compared in case no variation of breast. Conclusion: This study confirms the benefit of using a virtual bolus during VMAT and IMRT to compensate potential breast shape modification.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.899-908
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• 2004

The rise of income and introduction of 5 day a week working system give korean people opportunities to enjoy their leisure time. And many korean people have much interest in oceanic sports such as yachting and also oceanic leisure equipments. With the popularization and development of the equipments, the scope of oceanic activities has been expanding in Korea just as in the advanced oceanic countries. However, The current conditions for the sports in Korea are not advanced and even worse than underdeveloped countries. In order to develop the underdeveloped resources of Korean marina, we need to customize the marina models of advanced nations to serve the specific needs and circumstances of Korea As such we have carried out a comparative analysis of how Austrailia, Newzealand, Singapore, japan and Malaysia operate their marina, reaching the following conclusions. Firstly, in marina operations, in order to protect personal property rights and to preserve the environment, we must operate membership and non-membership, profit and non-profit schemes separately, yet without regulating the dress code entering or leaving the club house. Secondly, in order to accumulate greater value added, new sporting events should be hosted each year. There is also the need for an active use of volunteers, the generation of greater interest in yacht tourism, and the simplification of CIQ procedures for foreign yachts as well as the provision of language services. Thirdly, a permanent yacht school should be established, and classes should be taught by qualified instructors. Beginners, intermediary, and advanced learner classes should be managed separately with special emphasis on the dinghy yacht program for children. Fourthly, arrival and departure at the moorings must be regulated autonomically, and there must be systematic measures for the marina to be able, in part, to compensate for loss and damages to equipment, security and surveillance after usage fees have been paid for. Fifthly, marine safety personnel must be formed in accordance with Korea's current circumstances from civilian organizations in order to be used actively in benchmarking, rescue operations, and oceanic searches at times of disaster at sea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.551-560
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• 2016

The aim of this study was to verify the effect of the parameters in relation to college students' awareness of sexual assault and sexual violence experience. The subjects were 408 male and female college students attending four universities located in Jeju island. Sexual assault awareness measures, sexual violence experience scale, and the scale of sexual violence allowance scale were used in the questionnaires. First, correlation analysis showed a significant negative correlation between sexual violence awareness and sexual violence. Also, sexual violence awareness and sexual violence allowance scale showed a considerable negative correlation. This suggests that the higher the sexual assault awareness, the lower the sexual damage and sexual violence allowance scale. Second, after analyzing the division of the subject into research model and competition model to verify the mediation effect in relationship of the sexual violence awareness and sexual violence experience, it was clear that sexual awareness does not have a direct effect on the experience of sexual damage. It rather mediated the sexual violence allowance scale. Therefore, the research model, which is the full mediation model, was selected. In other words, sexual assault awareness appeared to fully mediate the relationship between sexual assault awareness and sexual assault experience. This means that sexual assault perception has an indirect influence through sexual assault allowance rather than a direct effect on the sexual assault experience. Thus, the more well established that sexual assault awareness is, the lower the sexual assault allowance scale. Finally, the lowered sexual assault allowance scale could reduce the sexual assault harm. To improve the sexual assault recognition, a systematic sexual violence prevention education should be conducted. Sexual assault prevention education would allow students in dating relationships to become mature in their human rights and maintain the proper emotional relationship and enable a reduction in the harm sexual assault as a result of giving them the consideration. Finally, this study had a limitation in selecting the subjects as the college students living in Jeju. Therefore, in order to compensate for this limitation, follow-up studies should be carried out on with a sample of generalized and various research subjects.

• Korean Journal of Environment and Ecology
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• v.31 no.3
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• pp.337-343
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• 2017

This study is going to contribute the activation of ecosystem services written in the 3rd National Basic Plan for Nature Conservation(2016~2025) in Korea. Meanwhile we considered the benefits that the nature has given to the humankind as free goods or services which we may consume traditionally without due payment therefore. But on account of the expansion of cities and expedition of development, as the carrying capacity of the nature has been breached, people have come to try to restore and enhance artificially such vulnerable capacity. It is necessary to compensate the opportunity cost which the land owners or occupiers have to pay for conservation and maintenance of natural capitals which yield the ecosystem services. Therefore the institutionalization of ecosystem services should be established that the consumers who enjoy such services should share the interest from enjoying services with the land owners or occupiers who produce the ecosystem services, under the legal system which will make it possible to connect the benefit sharing with the conservation of environment. However it is the first task that the present legal system could not realize the fair and equitable benefit sharing between the producers and consumers of ecosystem services. And the second task in such legal system is that the value of ecosystem services could not be fully considered in the process of development planning. According to the analysis of this study, the institutionalization of ecosystem services in the government side and the civilian side could be realized to somewhat extent, although not sufficient. Especially the transactions of ecosystem services through the private contract among stakeholder are possible in the course of development planning or without any relevancy to a development project. The final task in the institutionalization of ecosystem services is how to assess the ecosystem services and to value the economic benefits therefrom on the basis of what kinds of procedures relating to some development processes. To overcome such difficulties, it is necessary that the state, trend and change of ecosystem services confronting with a developing project should be assessed concretely at the threshold of development. It is possible to integrate the ecosystem services into the environmental impact assessment(IEA), not by way of the Act of IEA, but by way of the Decree thereof.

• Journal of the Korean Geotechnical Society
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• v.28 no.5
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• pp.13-25
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• 2012

Ground anchor method is one of the most popular reinforcing technology for slope in Korea. For the health monitoring of slope which is reinforced by permanent anchor for a long period, monitoring of the tension force of ground anchor is very important. However, since electromechanical sensors such as strain gauge and V/W type load cell are also subject to long-term risk as well as suffering from noise during long distance transmission and immunity to electromagnetic interference (EMI), optical FBG sensors embedded tendon was developed to measure strain of 7-wire strand by embedding FBG sensor into the center king cable of 7-wire strand. This FBG sensors embedded tendon has been successfully applied to measuring the short-term anchor force. But to adopt this tendon to long-term monitoring, temperature compensation of the FBG sensors embedded tendon should be done. In this paper, we described how to compensate the effect in compliance with the change of underground temperature during long-term tension force monitoring of ground anchors by using optical fiber sensors (FBG: Fiber Bragg Grating). The model test was carried out to determine the temperature sensitivity coefficient (${\beta}^{\prime}$) of FBG sensors embedded tendon. The determined temperature sensitivity coefficient ${\beta}^{\prime}=2.0{\times}10^{-5}/^{\circ}C$ was verified by comparing the ground temperatures predicted from the proposed sensor using ${\beta}^{\prime}$ with ground temperatures measured from ground thermometer. Finally, temperature compensations were carried out based on ${\beta}^{\prime}$ value and ground temperature measurement from KMA for the tension force monitoring results of tension type and compression type anchors, which had been installed more than 1 year before at the test site. Temperature compensated tension forces are compared with those measured from conventional load cell during the same measuring time. Test results show that determined temperature sensitivity coefficient (${\beta}^{\prime}$) of FBG sensors embedded tendon is valid and proposed temperature compensation method is also appropriate from the fact that the temperature compensated tension forces are not dependent on the change of ground temperature and are consistent with the tension forces measured from the conventional load cell.

• Journal of the Korean earth science society
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• v.24 no.8
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• pp.684-690
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• 2003

Recently Choongchung provinces in the central part of South Korea have received increasing attention because of the newly Planned administrative capital construction. In this area, a seismic network of Korea National University of Education has been installed since September 1996, and analyzed Q$_P^{-1}$ and Q$_S^{-1}$ by the extended Coda normalization method based on 60 events recorded by 2 stations of the network. To compensate for insufficient data, we combined the data from 33 events observed at 1 of the stations of the network of Korea Institute of Geology, Mining & Materials. Estimated Q$_P^{-1}$ and Q$_S^{-1}$ showed frequency dependence that decrease from (1.9${\pm}$3.0)${\times}$10$^{-3}$ and (2.4${\pm}$1.4)${\times}$10$^{-3}$ at 3.0 Hz to (5.4${\pm}$1.5)${\times}$10$^{-4}$ and (6.3${\pm}$1.1)${\times}$10$^{-4}$ at 24 Hz, respectively. Using a power law dependent on frequency, the best fit of Q$_P^{-1}$ and Q$_S^{-1}$ are 0.003f$^{-0.62}$ and 0.006f$^{-0.71}$ respectively. These values correspond to those of seismically stable regions, and are slightly less dependent on frequency than those of the southeastern part of Korea due to high Q$^{-1}$ values in high frequencies. Further observations are required in the central part of S. Korea to evaluate the difference of Q$^{-1}$ between central and southeastern parts of S. Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.52-58
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• 2004

The active principle responsible for lipid lowering in Chinese cabbage kimchi, 3-(4-hydroxyl-3'5'-dimethoxyphenyl)propionic acid, of molecular weight 226, was chemically synthesized and then used for the treatment of hypercholesterolemia in male New Zealand white rabbit. Hypercholesterolemia in rabbits were induced by feeding 0.5% cholesterol added chow diet for 5 weeks. Each experimental group has four rabbits in it. for the 1st experiment,3-(4-hydroxyl-3'5'-dimethoxyphenyl)propionic acid or simvastatin was injected to the ear vein of rabbit every other day for 16 days (2 mg/3 kg/2 days) while normal chow diet was provided. Blood was drawn every 4th day. For the 2nd experiment, all the experimental condition was same as the 1st trial except 0.5% cholesterol diet was provided while 16 days. Plasma cholesterol level was decreased when cholesterol in the diet was removed. Decreased in cholesterol in kimchi and simvastatin groups were 18.65 and 29.67%, respectively compared to the control when the normal diet was given, and cholesterol increase was inhibited by 33.79 and 21.81% for kimchi and simvastatin groups, respectively, when 0.5% cholesterol diet was provided. The drop in LDL-C level by the active principle of kimchi and simvastatin was not significant when normal diet was given, however the changes was significant (p<0.05), approximately 130% decrease, when 0.5% cholesterol diet was given. The 105% and 62% decreased in triglyceride concentration were observed from 0.5% cholesterol diet fed kimchi and simvastatin groups respectively HDL cholesterol levels in experimental groups were not changed significantly from the both trials. The HMG-CoA reductase activity of kimchi and simvastatin groups were found to be higher than that of control to compensate the hypercholesterolemic condition induced by 0.5% cholesterol diet in these groups. In conclusion, diet is an important factor to control the hypercholesterolemia besides drug treatment. 3-(4-hydroxyl-3'5'-dimethoxyphenyl)propionic acid that is the active principle in Chinese cabbage kimchi seems a beneficial to the hypercholesterolemia and its effect is comparable to that of simvastatin.