• Journal of Chest Surgery
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• v.31 no.9
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• pp.861-866
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• 1998

Background: Pulmonary atresia (PA) with ventricular septal defect has various morphology of pulmonary arteries and pulmonary blood flow sources, so pulmonary arterial hypoplasia and arborization abnormality make this anomaly difficult to manage surgically. In cases associated with juxtaductal stenosis, we evaluated the change of the pulmonary arterial and juxtaductal stenotic site after shunt operations, and would like to find useful information in surgical planning and methodology of these patients. Material and Method: Among 59 cases diagnosed as PA with ventricular septal defect associated with juxtaductal stenosis, 29 cases who had cardiac catheterization before and after shunt operation were selected from July, 1991 to July, 1996. In 10 cases of right shunt operation(Group I) and 19 cases of left shunt operation (Group II), the diameters of the descending aorta, both pulmonary arteries, and the juxtaductal stenosis site were measured before and after the shunt operation. Result: In both Group I and II, the pre- and postoperative ratio of diameters of the ipsilateral pulmonary artery to the descending aorta was from 0.78${\pm}$0.31 units to 1.01${\pm}$0.26 units and from 0.67${\pm}$0.18 units to 0.84${\pm}$0.27 units respectively, showing a signigicant increase. The contralateral pulmonary artery index was increased from 0.92${\pm}$0.28 units to 1.05${\pm}$0.15 units and from 0.94${\pm}$0.27 units to 1.08${\pm}$0.37 units respectively, but could not be confirmed statistically. In both groups, the change of juxtaductal stenosis showed an aggravating tendency but of no statistical significance from 0.43${\pm}$0.27 units to 0.39${\pm}$0.25 units and from 0.32${\pm}$0.10 units to 0.30${\pm}$0.16 units respectively, and we experienced 2 total obstruction in Group II. Because the increased pulmonary blood flow by shunt operation has a favorable effect to the pulmonary arterial growth, the shunt operation is a recommended treatment in patients with hypoplastic pulmonary arteries. But in PA with ventricular septal defects, the change of juxtaductal stenosis is very important. In conclusion, the growth of ipsilateral (shunt site) pulmonary artery was promoted by shunt operation, but there is a tendency for the juxtaductal stenosis to be aggravated. And we experienced 2 total obstruction in Group II. Conclusion: Thus, in cases operated with shunt method, much careful postoperative follow up study including angiographic evaluation is needed, and after the shunt operation on the side of pulmonary artery associated with juxtaductal stenosis, early precise planning for total correction is recommended.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.289-293
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• 2001

Objectives : The optimal treatment of craniopharyngioma is controversial. Despite recent advances in microsurgical management, complete surgical removal of craniopharyngioma remains very difficult. Radiation added to surgery is effective, but radiation therapy resulted in untoward side effect in young patient. Gamma knife radiosurgery offers the theoretical advantage of a reduced radiation dose to surrounding structures during the treatment of residual or recurrent craniopharyngioma compared with fractionated radiotheraphy. We described retrospective analysis of tumor size and clinical symptoms of patients after gamma knife radiosurgery in residual or recurrent craniopharyngioma were performed. Material and Methods : From September 1990 to January 2000, 18 patients of craniopharyngioma were treated by gamma knife radiosurgery. All patient had undergone surgery, but residual or recurrent tumor was found and all of them treated postoperative gamma knife radiosurgery. The mean age was 19(from 6 to 66) and male to female ratio was 10 to 8 and 8 patients were below 15 years old. In young age group(below age 15), the average volume of the tumor was $2904.8mm^3$ and mean maximal gamma knife dose was 34.9Gy. In old age group(older than 15), the average volume of the tumor was $2590.4mm^3$ and mean maximal gamma knife dose was 45.2Gy. The size of the tumor was average $2730.1mm^3$($88-12000mm^3$), mean average radiation dose was 40.7Gy and the mean prescription dose was 17.6 Gy(4-35Gy) delivered to a median prescription 50.7% isodose. Results : The follow up was from 1 year to 9 years(mean 59.1 months) after gamma knife radiosurgery. The tumor was controlled in 13(72.2%) patients. The tumor decreased in 9 patients and not changed in 4 patients. The tumor size increased in 4(22.2%) patients during follow up period. In two cases the tumor size increased because of its cystic portion was increased, but their solid portion of the tumor was not changed. In another two patients, the solid portion of the tumor was increased. So, one patient underwent reoperation and the other patient underwent operation and repeated gamma knife radiosurgery. The tumor recurred in one case(5.6%) that is a outside of irradiated site. The presenting symptoms were improved in 4 patients(improved visual acuity in 1, controlled increased intracranial presure sign in 3 patients). In one case, visual acuity decreased after gamma knife radiosurgery. The endocrine symptoms were not influenced by gamma knife radiosurgery. Conclusion : Craniopharyngioma can be treated successfully by gamma knife radiosurgery. Causes of the tumor regrowth are inadequate dose planning because of postoperatively poor margination of the tumor, close approximation of optic nerve and residual tumors outside the target lesion. Recurrence can develop 4 years after gamma knife radiosurgery. Volume is important, but the accurate targeting is more important to prevent tumor recurrence. If the tumor definition is not clear during planning gamma knife surgery, long-term image follow up is required.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.73-81
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• 2018

Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.1
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• pp.1-14
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• 2003

In this study, to take the object of this thesis on understanding the characteristics on marketing structure and marketing distribution of landscape materials after consideration in the side of prices trends which is important factors for analysis in understanding the market of landscape materials. To do this, Analysis is divided into the prices trends. The investigation of prices trends and marketing distribution are to collect data refer to purchases and sales reports, these results are used to analyzed the operative factor of forming market structure. The periodic range of this thesis is limited from 1996 to 2000 and analytic articles is limited on 609 landscape materials(planting materials : 567 articles, facility materials : 7 articles, the other : 35 articles). The results of the whole prices trends and marketing distribution survey can be summarized as follows : 1. Prices trends of showing 3 types of landscape materials : In cases of planting, facility and the others materials, the annual average increasing rate of the index number of price was 3.1%, 3.4%, 3.1% while the KPRC(Korea Price Research Center) price was 3.98% for the past five years. 2. GSP(Government Specified Prices) Prices trends of showing 3 types of landscape materials : In cases of planting, facility and the others materials, the annual average increasing rate of the index number of price was 3.7%, 1.2%, 2.6% while the KPRC(Korea Price Research Center) price was 3.98% for the past five years. This increase indicates a small price margin, particularly, the GSP price of planting materials should be adjusted to a realistic level. 3. Native and exotic product Prices trends of showing 3. types of landscape materials : In cases of Native planting, facility and the others materials, the annual average increasing rate of the index number of price was 3.2%, 3.2%, 3.6% while cases of exotic was 3.1%, 1.0%, 5.8% for the past five years. The index number increase of prices of exotic landscape materials were fluctuated more than those the native landscape materials.

• Korean Journal of Construction Engineering and Management
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• v.21 no.6
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• pp.84-94
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• 2020

Modular architecture is very important not only in the design phase but also in the construction planning phase because it affects construction methods and module sizes depending on transport equipment. There are economic risks as well as quality, as there may be defects such as internal interiors or elimination of deadlines during transportation, and structural torsion caused by rainfall and shock. However, there is a lack of objective criteria or data to refer to in determining transport equipment that has a material effect on transport. Accordingly, there is no decision model to determine the optimum transportation equipment for each construction site. Therefore, it is necessary to develop a decision support model that can be compared to the review of transport equipment selection factors. The purpose of this study is to propose the transport equipment impact factors and decision support models for systematic review and objective decision making of each construction plan in the construction of small and medium-sized modulators. The decision model proposed in this study can be used as basic data for transport studies, ensuring objectivity and transparency in the equipment selection process.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.67-77
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• 2010

Growth of oil and chemical industries has been remarkable during recent years. Hazardous materials (Hazmat) make frequent use in the wide range of industries. It increases the frequency of Hazmat transport and it leads to increase the number of accidents. Optimal Hazmat routes can reduce damage. Thus, the objective of this study is to minimize the areas impacted by Hazmat accidents by adopting experts' opinion in planning the route. We calculated weights using AHP (Analytic Hierarchy Process) and deduced the best route by applying this weights. Results showed that in the case of shortest route versus weighted route, the percentage of population damage has been decreased by 33.4% in the comparison between shortest route and optimally weighted route. And the percentage of environmental damage also has been decreased by 21.8%. Social damage has been decreased by 1521.7%. In the case of none weighted route versus weighted route, the percentage of population damage has been decreased by 2.6% when we adopted weighted route. Consequently, the recommended route with weighted risk assessment avoids densely populated area comparing with none weighted route. Further research needs to be carried out in order to figure out the specific cost-effectiveness analysis applying the equal cost unit for each factor.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.45-57
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• 2015

Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose($LD_{50}$) and median lethal concentration($LC_{50}$). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between "skin" and "no skin" substances which indicate skin penetration were not significantly different. Both $LD_{50}$ and $LC_{50}$ were correlated with TWA, while the $LC_{50}$ was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

• Journal of Distribution Science
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• v.14 no.2
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• pp.47-56
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• 2016

Purpose - The purpose of this study is to investigate the difference in the degree of significance and satisfaction perceived by college students and ordinary consumers on the HMR product attributes. Comparison of the difference on HMR product attributes between ordinary consumers and college students who belong to the current and future consumption groups of HMR will provide information for clear marketing strategies and PR on target consumers from the aspects of companies. Also, overall difference on HMR was investigated through IPA(importance-performance analysis) on significance and satisfaction with each product attribute. This result will provide information to food companies that produce or supply HMR products to be supplemented and improved. Finally, IPA was conducted between groups on product attribute to find which difference exists between groups. This result is also expected to provide crucial information to companies as suggested in the first purpose. Research design, data, and methodology - The procedure of analysis is as follows. First, independent sample t-test was conducted on the significance and satisfaction on HMR product attributes. Second, with using IPA, the significance and satisfaction on HMR product attributes of the respondents were checked to investigate marketing strategy direction on overall HRM products. Third, the difference between generations was verified using IPA on the college student and consumer groups. According to this result, the direction of marketing strategy on HRM products was to be proposed to food companies. Results - It was known that consumers consider HMR product attributes statistically and significantly such as nutrient content(nutrition), country of origin, brand, main raw material, packaging, and awareness of manufacturer. They keep after purchase more importantly than college students who considered only volume and price than consumers. In comparison with the difference in satisfaction on HMR product attributes, the college student group was more satisfied than ordinary consumers only in flavor, condition of food additives, and volume. Also, HMR related food companies must maintain taste, cooking method, manufacturing date, expiration date, and safety on current products continuously. Finally, as a result of analysis from the groups, the attributes such as cooking method, manufacturing date, expiration date, and safety were considered significantly with high achievement by the two groups. It was known that college students considered food texture to be important, but consumers considered storage method to be important after purchasing it. Conclusions - There is necessity to differentiate effectiveness of products when releasing HMR products subject to consumers and college students. The result will give great assistance to the improvement of companies, produce or supply HMR products. It will also provide entry strategies on target groups of companies that are planning for entry. The factors that consumers commonly considered not to be significant were brand, package form(appearance), cooking time, and sale(purchase) location, which were found in the comparison with the groups that awareness about manufacturers and storage method after purchase corresponded to college students and that distribution route corresponded to ordinary consumers.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.637-645
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• 2019

Due to the transformation to the intelligent information society, the rapid change of our life and environment is expected. The Ministry of Science and ICT (MSIT) and the National Research Council of Science and Technology (NST) introduced a five-year government supported research institution's planning and evaluation based on the mid-to long-term perspective. This study collects international benchmarking information including industry, academia, and research fields by collecting mid- and long-term strategy reports from public research institutes, surveys by experts from abroad universities and research institutes, and analyzing overseas market information reports. The British Geological Survey (BGS), the U.S. Geological Survey (USGS) and the japanese geological survey related institutes (AIST-GSJ) plans for three-dimensional national geological information, predictions of geological environmental disasters, and development of important metals and material in the low carbon economic transformation and in the era of the Fourth Industrial Revolution. The mid- and long-term program emphasizes basic and public research on geological information through abroad experts survey such as the IPGP-CNRS etc. The market analysis of the mining automation and digital map sectors has been able to derive the fields in which the role of public research institutes by the market is expected such as data collection on land and in the air, mobile or three-dimensional information production, smooth/fast/real-time maps, custom map design, mapping support to various platforms, geological environmental risk assessment and disaster management information and maps.

• Progress in Medical Physics
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• v.28 no.3
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• pp.100-105
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• 2017

The purpose of the present study was to develop and evaluate patient-customized helmets with a three-dimensional (3D) printer for radiation therapy of malignant scalp tumors. Computed tomography was performed in a case an Alderson RANDO phantom without bolus (Non_Bolus), in a case with a dental wax bolus on the scalp (Wax_Bolus), and in a case with a patient-customized helmet fabricated using a 3D printer (3D Printing_Bolus); treatment plans for each of the 3 cases were compared. When wax bolus was used to fabricate a bolus, a drier was used to apply heat to the bolus to make the helmet. $3-matic^{(R)}$ (Materialise) was used for modeling and polyamide 12 (PA-12) was used as a material, 3D Printing bolus was fabricated using a HP JET Fusion 3D 4200. The average Hounsfield Unit (HU) for the Wax_Bolus was -100, and that of the 3D Printing_Bolus was -10. The average radiation doses to the normal brain with the Non_Bolus, Wax_Bolus, and 3D Printing_Bolus methods were 36.3%, 40.2%, and 36.9%, and the minimum radiation dose were 0.9%, 1.6%, 1.4%, respectively. The organs at risk dose were not significantly difference. However, the 95% radiation doses into the planning target volume (PTV) were 61.85%, 94.53%, and 97.82%, and the minimum doses were 0%, 77.1%, and 82.8%, respectively. The technique used to fabricate patient-customized helmets with a 3D printer for radiation therapy of malignant scalp tumors is highly useful, and is expected to accurately deliver doses by reducing the air gap between the patient and bolus.