• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.113-122
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• 2007

Purpose: We proposed the method using dose-volume Histogram index to compare prospective plan trials in tomotherapy planning optimization. Materials and Methods: For 3 patients in cranial region, thorax and abdominal region, we acquired computed tomography images with PQ 5000 in each case. Then we delineated target structure and normal organ contour with pinnacle Ver 7.6c, after transferred each data to tomotherapy planning system (hi-art system Ver 2.0), we optimized 3 plan trials in each case that used differ from beam width, pitch, importance. We analyzed 3 plan trials in each region with isodose distribution, dose-volume histogram and dose statistics. Also we verified 3 plan trials with specialized DVH-indexes that is dose homogeneity index in target organ, conformity index around target structure and dose gradient index in non-target structures. Results: We compared with the similarity of results that the one is decide the best plan trial using isodose distribution, dose volume histogram and dose statistics, and the another is using DVH-indexes. They all decided the same plan trial to better result in each case. Conclusion: In some of case, it was appeared a little difference of results that used to DVH-index for comparison of plan trial in tomotherapy by special goal in it. But because DVH-index represented both dose distribution in target structure and high dose risk about normal tissue, it will be reasonable method for comparison of many plan trials before the tomotherapy treatments.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.153-160
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• 2018

Purpose : We retrospectively analyzed doses of each radiation therapy technique used in the treatment for left breast cancer patients after partial mastectomy through dose results for normalorgans and tumor volume to use this as a clinical reference for radiation therapy of domestic left breast cancer patients. Materials and Methods : 40 patients who underwent partial mastectomy on left breast cancer were classified in 3 treatment methods. The treatment plan was evaluated by HI(homogeneity index), $D_{95%}$, and CI(conformity index), and the $V_{hot}$ for gross tumor volume and clinical target volume of each treatment method. In Cyberknife treatment, tumor volume was the same as high dose volume in the other techniques, so no consideration was given to clinical target volume. Treatment plan evaluation for normal organs were evaluated by mean dose on ipsilateral lung, heart, left anterior descending artery, opposite breast and lung, and non-target tissue. Result : Treatment with volumetric arc radiotherapy(VMAT) showed $95.84{\pm}0.75%$ of $D_{95%}$ on the clinical target volume, significantly higher than that of 3D-CRT. The $D_{95%}$ value of the total tumor volume was slightly higher than the other treatments. In Cyberknife treatment, the dose to the normal organs was significantly lower than other treatments. Overall, the maximum dose and mean dose to the heart were $26.2{\pm}6.12Gy$ and $1.88{\pm}0.2Gy$ in VMAT treatment and $20.25{\pm}9.35Gy$ and $1.04{\pm}0.19Gy$ in 3D-CRT therapy, respectively. Conclusion : In comparison on 3D-CRT and VMAT, most of the dosimetric parameters for the evaluation of the treatment plan showed similar values, so that there is no significant difference in treatment plan evaluation. It is possible to select the treatment method according to the patient's anatomical structure or possibility of breath control. Cyberknife treatment is very useful treatment for normal organs because of its accurate dose exposure to the tumor volume However, it has restrictions to treat the local area, to have relatively long treatment time and to involve invasive procedure.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.33-41
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• 2019

Purpose : To evaluate the effectiveness of Jaw-tracking(JT) technique in Intensity-modulated radiation therapy(IMRT) and Volumetric-modulated arc therapy(VMAT) for radiation therapy of esophageal cancer by analyzing volume dose of perimetrical normal organs along with the low-dose volume regions. Materials and Method: A total of 27 patients were selected who received radiation therapy for esophageal cancer with using $VitalBeam^{TM}$(Varian Medical System, U.S.A) in our hospital. Using Eclipse system(Ver. 13.6 Varian, U.S.A), radiation treatment planning was set up with Jaw-tracking technique(JT) and Non-Jaw-tracking technique(NJT), and was conducted for the patients with T-shaped Planning target volume(PTV), including Supraclavicular lymph nodes(SCL). PTV was classified into whether celiac area was included or not to identify the influence on the radiation field. To compare the treatment plans, Organ at risk(OAR) was defined to bilateral lung, heart, and spinal cord and evaluated for Conformity index(CI) and Homogeneity index(HI). Portal dosimetry was performed to verify a clinical application using Electronic portal imaging device(EPID) and Gamma analysis was performed with establishing thresholds of radiation field as a parameter, with various range of 0 %, 5 %, and 10 %. Results: All treatment plans were established on gamma pass rates of 95 % with 3 mm/3 % criteria. For a threshold of 10 %, both JT and NJT passed with rate of more than 95 % and both gamma passing rate decreased more than 1 % in IMRT as the low dose threshold decreased to 5 % and 0 %. For the case of JT in IMRT on PTV without celiac area, $V_5$ and $V_{10}$ of both lung showed a decrease by respectively 8.5 % and 5.3 % in average and up to 14.7 %. A $D_{mean}$ decreased by $72.3{\pm}51cGy$, while there was an increase in radiation dose reduction in PTV including celiac area. A $D_{mean}$ of heart decreased by $68.9{\pm}38.5cGy$ and that of spinal cord decreased by $39.7{\pm}30cGy$. For the case of JT in VMAT, $V_5$ decreased by 2.5 % in average in lungs, and also a little amount in heart and spinal cord. Radiation dose reduction of JT showed an increase when PTV includes celiac area in VMAT. Conclusion: In the radiation treatment planning for esophageal cancer, IMRT showed a significant decrease in $V_5$, and $V_{10}$ of both lungs when applying JT, and dose reduction was greater when the irradiated area in low-dose field is larger. Therefore, IMRT is more advantageous in applying JT than VMAT for radiation therapy of esophageal cancer and can protect the normal organs from MLC leakage and transmitted doses in low-dose field.

• Korean Journal of Remote Sensing
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• v.28 no.5
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• pp.587-596
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• 2012

Verifying about eligibility of targeted site is necessary for execute Afforestation and Reforestation Clean Development Mechanism (A/R CDM) project which is followed by system of Kyoto protocol. The site have to be identified by which could not be in conformity with definition of forest. This study tried to propose a technology of classify for site selection of A/R CDM. We chose several parts of Yangpyeng as study area and applied LiDAR data and remotely sensed imagery for considering about tree height, degree of crown closure, and land area which 3 factors for identify forest. LiDAR data was used for offset the shortage of remotely sensed imagery that cannot perfectly determine the forest definition due to absence of 3-dimentional information, but can be obtained from LiDAR. Considering tree height, degree of crown closure, and land area simultaneously by moving window, classified fields to forest and non forest based on pixel size. As a result, 124.06 ha for suitable to doing plantation and approximately 357.02 ha are in negative. Technology that applied for analyzing will provide fundamental methodology not only site selection for A/R CDM, but will be utilized in other Kyoto protocol.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.2
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• pp.138-145
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• 2017

The purpose of this study is to establish a reasonable analytical method for the estimation of overall behavior characteristic from cracking to yielding of rebar and crushing of concrete and seismic performance of reinforced concrete shear wall with high-strength reinforcing bar. A total of 8 specimens of reinforced concrete walls which have constant aspect ratio and a variety of variables such as reinforcement ratio, reinforcement yielding strength, reinforcement details, concrete design strength, section shape and whether lateral restraint hoop were selected and the analysis was performed by using a non-linear finite element analysis program (RCAHEST) applying the proposed constitutive equation by the authors. The mean and coefficient of variation for maximum load from the experiment and analysis results was predicted 1.04 and 8%. The mean and coefficient of variation for displacement corresponding maximum load from the experiment and analysis results was predicted 1.17 and 19% respectively. The analytical results were predicted relatively well the fracture mode and the overall behavior until fracture for all specimens. These results are expected to be used as basic data for application of high-strength reinforcing bar to design codes in the future.

• Korean Journal of Clinical Pharmacy
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• v.27 no.1
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• pp.15-21
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• 2017

Objective: The perioperative management of antithrombotic therapy is often challenging and it requires a fine balance between the risk of hemorrhage and thrombosis. We aimed to evaluate the antithrombotic management for moderate to high risk patients in real world setting. Methods: Among the patients who were consulted to the neurologist for the evaluation of perioperative risk from 2010 to 2012, patients undergoing moderate to high risk surgery and taking antithrombotics within 30 days were identified. We analyzed the timing of discontinuation and reinitiation of antithrombotic drugs before or after surgery as well as the status of bridging therapy. In addition, the conformity with the guideline suggested by American College of Chest Physicians was assessed. The rate of thromboembolic event and major hemorrhage were also investigated. Results: A total of 329 patients were included. The concordance rate of warfarin stop and restart time with guideline was 23.4% and 10.3%, respectively. Continuing aspirin in patients undergoing coronary artery bypass surgery or non-cardiac surgery in patients with high risk for cardiovascular events were 59.2% and 2.6%, respectively. Bridging therapy was adopted in 92.9% and 81.2% in patients who had received anticoagulant before surgery and who were at high and low risk thromboembolism, respectively. In entire cohorts, 30-day incidence of major bleeding and thromboembolic event were 31.9% and 3.0%. Co-morbid renal disease were shown as independent predictor for major bleeding (adjusted OR 2.65. 95% CI 1.33-5.28). Conclusion: The concordance rate with guideline regarding perioperative antithrombotic use was low and bridging therapy was prevalent in patients undergoing moderate to high risk surgery.

• Journal of Environmental Health Sciences
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• v.44 no.3
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• pp.283-292
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• 2018

Objectives: This study was conducted to identify hazardous factors that reflect the characteristics of the academy and to provide basic data of environmental safety standard. Methods: Heavy metals, volatile organic compounds, formaldehyde, pesticides and phthalates were measured in 20 academies, which were supplementary, music, art and physical education institutes. Results: In case of heavy metals, the 12 locations were detected for lead (Pb) over the standard value, and 15 locations were exceeded for the total heavy metal. In six locations, the concentrations of volatile organic compounds were exceeded the standard value of $400{\mu}g/m^3$, and two locations for formaldehyde were exceeded the standard value of $100{\mu}g/m^3$. The most commonly detected agents in the air dust were chlorpyrifos and diazinon. The concentrations of DEHP, DINP, and DBP were detected and exceeded in several academies, The risk assessment results showed that HCHO as carcinogen had a safety level of 10-7 to 10-6, and DEHP and DINP as non-carcinogens had a safety level as assessed to be under than 0.1. Conclusions: Through the investigation of long-term environmental and health effects related laws on academies, indoor air quality management might be needed because there were cases of exceeding standard.

• Korean Institute of Interior Design Journal
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• v.26 no.4
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• pp.42-56
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• 2017

In Korea, which has three sides of the sea, various waterfront spaces are being developed and developed along with various coastal landscapes. However, there are a lot of cases that do not consider the regional characteristic of the coast or the characteristic of the coastal landscape. In many cases, the street facilities cause the landscape degradation and the use inconvenience because of incongruity with the scenery, aging and lax management. Therefore, it is necessary to reflect the specificity of the coastal landscape in planning and directing the street facilities, harmonizing with the surrounding natural environment, and consideration of sustainability. However, there is no research or planning index for sustainable street facilities considering the coastal characteristics. Therefore, this study suggests plan elements to improve the sustainability of the street facilities on the shore and proposes them as basic plan elements, and suggests what kind of improvements should be made to improve the sustainability of coastal facilities in Korea. Based on the plan elements derived from the plan, we checked the problems and complementary points of coastal street facilities in Korea by analyzing the current status of the street facilities around the Jeju Island beach from a sustainable point of view, and suggested plan indicators that should be supplemented to improve sustainability. We surveyed the street facilities such as walkway blocks, benches, pagoda, drinking fountain, trash cans, bicycle shelters, fences, guide maps, streetlights, and shower rooms in 10 beaches in Jeju Island. This study analyzed the sustainability characteristics of the each factor of these facilities by surveying the reflectivity of the 23 plan indicators from the six aspects derived from the sustainability planning factor as conformity, partial reflection, non - reflection, and nonconformity. The results of the analysis showed that the functional aspect was the highest with 68.3%, the material aspect (53%), the landscape aspect (22.3%), the productive aspect (14.7%) and the morphological aspect (12.2%), and maintenance / management (10.6%). In addition, the facilities with the lowest fitness in each aspect are bicycle shelter in landscape aspect, bicycle storage box and trash can in form aspect, shower room in material aspect, trash can in functional aspect, showroom, guide maps and drinking fountain in product aspect, showroom In maintenance aspect. In order to improve the sustainability of coastal facilities in the future, it is necessary to complement the administrative and landscape aspects. In coastal facilities, it is necessary to consider the sustainability planning index, especially for showers, taking into account the specificity of beaches. Consideration should be given to various aspects of sustainability for bike shelters and trash facilities. Through this study, we have proposed the plan elements to systematize, supplement, and improve the planning index for sustainability improvement in coastal facilities planning.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.629-636
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• 2013

There is no safety evaluation index with marine accidents and information of ship's safety management result for good grasp of safety management level of shipping company and effective monitoring. In this paper, we proposed a SMEI(Safety Management Evaluation Index) for evaluation of shipping companies. The SMEI is consist of MAR(marine accidents ratio), SSMR(ship safety management ratio) and SAP(safety advantage point) through brainstorming of the expert group and AHP(analysis hierarchy process)in previous study. And weights of SMEI are calculated using experts's opinions through the Delphi method. We also verified the validity of proposed SMEI to 119 Korean shipping companies with 916 ocean-going ships of Korean flag, which grouped three part (small, mid and big) by number of ship and gross tonnage. And we found out 19 shipping companies, 8 companies in group1 & group2 respectively and 3 companies in group 3, with score below 1.0 by SMEI. In these companies, there are no marine accidents in recent 3 years and appeared low frequency remarkably in the detention and mojor non-conformity by data analysis.

• Journal of the Korea Concrete Institute
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• v.19 no.3
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• pp.293-300
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• 2007

In Korea, the seismic design regulations was established since 1988 about regularity scale of structures. However, It was not established about seismic performance and evaluation method as the most existing buildings was constructed before Earthquake-Resistant Design(1988). In this study, for model structures which are 4 units of non-seismic designed apartment and 3 units of seismic designed in Korea performed seismic performance evaluation by suggested KISTC (2004). And the result compare to evaluate Capacity Spectrum Method by using MIDAS Gen and SDS. As a result, we observed that suggested KISTC's method have overestimated for shear stress and drift index. The purpose of this study provides most conformity seismic performance evaluation process and the appropriate method of calculating the seismic performance index in Korea.