• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.11-19
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• 2014

Purpose : To derive the most appropriate factors by considering the effects of the major factors when applied to the optimization algorithm, thereby aiding the effective designing of a ideal treatment plan. Materials and Methods : The eclipse treatment planning system(Eclipse 10.0, Varian, USA) was used in this study. The PBC (Pencil Beam Convolution) algorithm was used for dose calculation, and the DVO (Dose Volume Optimizer 10.0.28) Optimization algorithm was used for intensity modulated radiation therapy. The experimental group consists of patients receiving intensity modulated radiation therapy for the head and neck cancer and dose prescription to two planned target volume was 2.2 Gy and 2.0 Gy simultaneously. Treatment plan was done with inverse dose calculation methods utilizing 6 MV beam and 7 fields. The optimal algorithm parameter of the established plan was selected based on volume dose-priority(Constrain), dose fluence smooth value and the impact of the treatment plan was analyzed according to the variation of each factors. Volume dose-priority determines the reference conditions and the optimization process was carried out under the condition using same ratio, but different absolute values. We evaluated the surrounding normal organs of treatment volume according to the changing conditions of the absolute values of the volume dose-priority. Dose fluence smooth value was applied by simply changing the reference conditions (absolute value) and by changing the related volume dose-priority. The treatment plan was evaluated using Conformal Index, Paddick's Conformal Index, Homogeneity Index and the average dose of each organs. Results : When the volume dose-priority values were directly proportioned by changing the absolute values, the CI values were found to be different. However PCI was $1.299{\pm}0.006$ and HI was $1.095{\pm}0.004$ while D5%/D95% was $1.090{\pm}1.011$. The impact on the prescribed dose were similar. The average dose of parotid gland decreased to 67.4, 50.3, 51.2, 47.1 Gy when the absolute values of the volume dose-priority increased by 40,60,70,90. When the dose smooth strength from each treatment plan was increased, PCI value increased to $1.338{\pm}0.006$. Conclusion : The optimization algorithm was more influenced by the ratio of each condition than the absolute value of volume dose-priority. If the same ratio was maintained, similar treatment plan was established even if the absolute values were different. Volume dose-priority of the treatment volume should be more than 50% of the normal organ volume dose-priority in order to achieve a successful treatment plan. Dose fluence smooth value should increase or decrease proportional to the volume dose-priority. Volume dose-priority is not enough to satisfy the conditions when the absolute value are applied solely.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.1
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• pp.73-78
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• 2015

Purpose : Under the assumption of change to the amplitude based sorting, the study will use four dimensional computed tomography imaging (4DCT) arrayed using the phase based sorting to analyze the respiratory phase difference. Materials and Methods : The study analyzed the 4DCT (4-dimensional computed tomography) images of 10 liver cancer patients that were treated with respiratory gated radiotherapy from 2015 February to March. Using RPM respiratory gating (RPM 1.7.5, Varian, USA) equipment, imaging according to respiratory cycle of phase based sorting was acquired and using a treatment planning system (Pinnacle 9.2, Philips, USA) the acquired imaging according to respiratory cycle was used to measure the abdominal movement value by respiratory cycle. The measuring point was the point where the center point of the Marker Block and the body surface met in the 50% phase image and here the coordinate values Lateral, Vertical, Longitudinal (X, Y, Z) were set as reference points, and on the X, Z plane identical to the reference point, using the identical method the Y axis coordinate value of each 0%, 30%, 40%, 50%, 60%, 80% phase images were acquired to quantitatively measure the variation of distance to the Y axis. The abdominal movement value according to respiration was applied to the theoretical model that the value decreases linearly from maximum inhalation to maximum exhalation to divide the variation of my value to predict as amplitude value by respiratory cycle and conversely the variation in amplitude was recalculated with the phase variation deviation value to analyze. Results : The deviation value between expected value and actual location was the largest in the 30% phase with 0.24 cm, and standard deviation was also the largest in 30% phase with 0.13 cm. The effective value of the deviation value derived from the average of the deviation squared value of each patient appeared as minimum 0.7 cm, maximum 0.18 cm, average 0.12 cm, and standard deviation 0.4 cm. Also by dividing the actual movement distance value with the peak expiration value then converting it into %Phase, the deviation value with actual phase 16.5% in 30% phase, 10.0% and 40% phase, 10.0% and 60% phase, 15.4% and 80% phase, and overall average about 13%, and arraying based on amplitude, phase shift occurred and further it was from peak expiration the chance of deviation occurrence was increasingly measured. Conclusion : Based on the results of the study there were differences between value acquired based on theoretical model and actual value. Therefore in respiratory gated radiotherapy using external surrogates, there needs to be establishment of respiration gated radiation system that avoids the combination of two Sorting methods considering that there will be occurrence of treatment and corresponding clinical differences due to the phase difference that occur due to the Amplitude based Phase Sorting.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.2
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• pp.107-115
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• 2007

Among public transportation facilities within urban area, electric railway (subway) has been a regionally based facility that has played an important role in improving the foundation of territory development and arrangement of living foundation and living environment while supplementing the regional road network. In this regard, the subway stations should be allocated in the right place to ensure mobility, convenience and economic feasibility, some of transportation characteristics of road network combined with the subway. However, it would be very hard to evaluate quantitatively the effects of public transportation facilities such as subway in metropolitan cities on regional development and change in land use and to suggest the data that would be utilized in future city planning corresponding to their results. Therefore, this study evaluated the change in land use by the conditions of location of subway stations quantitatively; then, it evaluated and analyzed the change in land use for the internal and external parts of the surrounding areas of subway stations through the GIS spatial analysis and classification of landsat TM satellite image for utilizing it as reference material for the new establishment of subway stations in the future.

• Progress in Medical Physics
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• v.28 no.3
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• pp.111-121
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• 2017

Verification of dose distribution is an essential part of ensuring the treatment planning system's (TPS) calculated dose will achieve the desired outcome in radiation therapy. Each measurement have uncertainty associated with it. It is desirable to reduce the measurement uncertainty. A best approach is to reduce the uncertainty associated with each step of the process to keep the total uncertainty under acceptable limits. Point dose patient specific quality assurance (QA) is recommended by American Association of Medical Physicists (AAPM) and European Society for Radiotherapy and Oncology (ESTRO) for all the complex radiation therapy treatment techniques. Relative and absolute point dose measurement methods are used to verify the TPS computed dose. Relative and absolute point dose measurement techniques have a number of steps to measure the point dose which includes chamber cross calibration, electrometer reading, chamber calibration coefficient, beam quality correction factor, reference conditions, influences quantities, machine stability, nominal calibration factor (for relative method) and absolute dose calibration of machine. Keeping these parameters in mind, the estimated relative percentage uncertainty associated with the absolute point dose measurement is 2.1% (k=1). On the other hand, the relative percentage uncertainty associated with the relative point dose verification method is estimated to 1.0% (k=1). To compare both point dose measurement methods, 13 head and neck (H&N) IMRT patients were selected. A point dose for each patient was measured with both methods. The average percentage difference between TPS computed dose and measured absolute relative point dose was 1.4% and 1% respectively. The results of this comparative study show that while choosing the relative or absolute point dose measurement technique, both techniques can produce similar results for H&N IMRT treatment plans. There is no statistically significant difference between both point dose verification methods based upon the t-test for comparing two means.

• Journal of Korean Library and Information Science Society
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• v.48 no.3
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• pp.207-232
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• 2017

Recent efforts to systematically transfer older materials from local library collections to preserve in a cooperative preservation facility, such as regional main library, are being made in each region. The study, in this regard, sheds light the regional preservation program, as it identifies status of preservation in local libraries and analyze the opinions of librarians in order to illustrate the planning process of regional preservation program. Based on the data about preservation status of public library in Busan metro area, the study focused on the strategies to operate a cooperative preservation program for public libraries. Specifically, 1) it investigates the preservation status of public library in Busan area and the librarians' opinion on a cooperative preservation facility in Busan library. 2) It adds a proposal composed with a materials transfer strategy and a space management program.

• Journal of Environmental Impact Assessment
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• v.13 no.2
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• pp.57-71
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• 2004

This study aims to review the environmental impact assessment systems of Japanese local governments, to compare its outcome with the systems of Korean local governments, and to suggest the development direction for the environmental impact assessment systems of Korean local governments based on the result. The study results showed that, first, due to distinction in the political systems of Japan and Korea, while Japan has bottom-up environmental impact assessment systems, Korea has topdown environment impact assessment systems. Second, although introduction of national systems on planning was put on hold as a future initiative, local governments including Tokyo and Saitama are experimenting evaluation procedures tailored to local features by legislating them as regulations. On the other hand, while 'prior environmental review system' was in effect as a national system, nothing was practiced at all by local governments. Third, in a total of 47 Japanese local governments, about 45 projects and 44 assessment items were added to local government environmental impact assessment only and designated as target projects and assessment items. Fourth, in both national and local environment impact assessment systems in Japan, screening procedures to determine assessment by separating into Type 1 projects and Type 2 projects and scoping procedures to discuss assessment items in advance were introduced and in effect. This Japanese EIA system may serve as a good reference to the Korean national and local government EIA systems.

• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.617-626
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• 2011

Home appliance proposes the experience of new lifestyle to consumers, together with digital technology-applied highly advanced functions, beyond its natural quality like the basic function of reducing the burden of housework. However, under the current circumstances that populations are rapidly aging, the number of elderly consumers, who feel it inconvenient to smoothly use even the basic function of home appliance, is increasing in proportion to populations. Therefore, the necessity for developing home appliance with improved usability in consideration of the elderly is rising up. This study analyzed the elderly's pattern of using home appliance and illustrated the procedure of their using home appliance, putting its focus on the home appliance that the elderly highly depend on in keeping their daily life and that they feel it inconvenient to control. And based on the illustrated procedure, this paper substituted various kinds of home appliance that were not surveyed by this study and found out 4 user behavioral models for home appliance. Same as the concept of universal design, product designs, which are convenient to use by the elderly whose physical functions are reduced, are expected acceptable to various user classes. The found user behavioral models purport to give references to design process for product planning and design solutions.

• Korean Institute of Interior Design Journal
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• v.23 no.5
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• pp.131-138
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• 2014

The purpose of this study is to examine spatial composition elements of the public sector through medium-sized first class urban hotels of Korea and Japan, the two countries with geopolitical closeness and high cultural and economic correlation, and to provide data needed for devising future urban hotel plans. The scope of this study included case studies on medium-sized first class urban hotels (10 urban hotels with concours composition type in the public sector) located in downtowns of Korea (5 hotels) and Japan (5 hotels). The study was conducted by analysis of drawing based on review of preceding studies and literature, and on-site survey. The results of survey and analysis on physical spatial elements shown in medium-sized urban hotels of Korea and Japan with concours composition type among composition types in the public sector are as follows. First, as a result of analyzing spatial elements of medium-sized urban hotels in the public sector, an in-depth checklist must be prepared with consideration on intimate correlation between elements to devise a construction spatial plan for urban hotel in the future. Second, as a result of comparatively analyzing area ratio for each function (public sector, sales sector and service sector) through area analysis on the lower floors of medium-sized urban hotels, reference data for planning were found in regards to spatial composition ratio of the public sector. Third, as a result of analyzing spatial elements of lobby hall and traffic line of visitors on the lower floors of medium-sized urban hotels in the public sector, there was a substantial difference between hotels of Korea and Japan.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2770-2776
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• 2011

Mutual Interference scenarios between Wireless Broadband (WiBro) and Wireless LAN (WLAN) in DTV bands are assumed. Co-channel interference and adjacent channel interference are respectively evaluated in terms of carrier to interference ratio (C/I) by using Spectrum Engineering Advanced Monte Carlo Analysis Tool (SEAMCAT) based on the Monte-Carlo simulation method. For the simulation, three frequencies such as 185 MHz, 481 MHz and 687 MHz are chosen. Analysis results indicate that interference situation of using frequency of 185 MHz is the worst case, which requires longer protection distance between WiBro MS and WLAN User Equipment (UE), lower transmit power of WiBro Mobile Station (MS) and WiBro Base Station (BS) and WLAN UE and larger guard band. Comparing to cases of using frequency of 185 MHz and 481 MHz, interference situation of using frequency of 687 MHz is slighter. Therefore, using frequency of 687 MHz is easier for coexistence between WiBro and WLAN. Analysis results can be used as reference and guideline when planning the deployment of WiBro and WLAN in DTV bands.

• Journal of Korean Library and Information Science Society
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• v.47 no.1
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• pp.279-303
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• 2016

This study proposes the Book-Curation service as part of the information service offered through school library websites. Also, this study aims to establish recommendation standards for curation prior to detailed system planning. For such service, the following tasks were carried out. First, the list of recommended books of existing systems were analyzed to identify the attributes that can be used for recommendation in the user and book information. Second, the analyzed attributes were utilized to establish 12 recommendation standards. Finally, a survey was carried out to identify the user preferences as to each standards. The results are as follows. First, the majority of students responded that curation service is necessary for using a library. Second, the top three standards are as follows: "best lending books based on the keywords of individual users"; "best lending books of the same year students"; "best lending books on the textbook-related reference booklist".