• Journal of Korean Society for Geospatial Information Science
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• v.23 no.2
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• pp.27-38
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• 2015

In this study, the 3D position coordinates were calculated for the targets using DLT and self-calibration bundle adjustment with additional parameters in close-range photogrammetry. And then, the accuracy of the results were analysed. For this purpose, the results of camera calibration and orientation parameters were calculated for each images by performing reference surveying using total station though the composition of experimental conditions attached numerous targets. To analyze the accuracy, 3D position coordinates were calculated for targets that has been identically selected and compared with the reference coordinates obtained from a total station. For the image coordinate measurement of the stereo images, we performed the ellipse fitting procedure for measuring the center point of the circular target. And then, the results were utilized for the image coordinate for targets. As a results from experiments, position coordinates calculated by the stereo images-based photogrammetry have resulted out the deviation of less than an average 4mm within the maximum error range of less than about 1cm. From this result, it is expected that the stereo images-based photogrammetry would be used to field of various close-range photogrammetry required for precise accuracy.

• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.320-325
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• 2021

In this study, an optimization for the production of water emulsion was designed by adding an extract of wheat sprout, which is known to contain a large amount of antioxidants. The central composite design of reaction surface analysis method (CCD-RSM) was used for the optimization process. The amount of emulsifier, emulsification time, and added amount of wheat sprout extract were selected as independent variables based on our preliminary experiments. The mean droplet size (MDS), viscosity, and emulsion stability index (ESI) were set as the responses to evaluate the stability of the emulsion. For each independent variable, the P-value and coefficient of determination were evaluated to verify the reliability of the experiments. From the result of CCD-RSM, optimum conditions for the emulsification were determined as 23.6 min, 7.7 wt.%, and 3.9 wt.% for the emulsification time, amount of emulsifier, and amount of sprout, respectively. From the optimized condition obtained, MDS, viscosity, and ESI after 7 days from reaction were estimated as 252.3 nm, 616.7 cP, and 88.7%, respectively. The overall satisfaction was 0.9137, which supported the validity of the experiments, and the error rate was measured at 0.5% or less by advancing the experiments. Therefore, an optimized process for producing an emulsion by adding the malt extract was designed by the CCD-RSM.

• Journal of Service Research and Studies
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• v.13 no.3
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• pp.160-171
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• 2023

The importance of design utilization as a method for establishing policies and services in the public sector is increasing. Accordingly, Korea has introduced a public service design development method and has implemented and operated a national design group for consumer-centered policy development since 2014. This study analyzes the cases of the National Design Group to expand the use of design in the public sector and propose sustainable public service design strategies. The time range of this study is from 2014 to 2021, when the National Design Group was implemented, and the content is limited to tasks that can be found on the Gwanghwamun 1st Street website and the National Design Group casebook. This study was conducted as follows. First, we looked for implications for how to use and identify the role of design in the public policy development stage by referring to the literature on design policy and public service design, and second, based on major implications, we analyzed the task name and contents. Based on literature studies and case studies, we found implications that design can be used in various public fields, and the policy implications proposed to expand the use of sustainable design in the public sector are as follows. First, by raising awareness of service design in public policies and services, it continues to provide opportunities for the use of design to expand as a role that leads to voluntary behavioral changes of citizens beyond civic participation. Second, more active publicity is needed for the successful cases of the National Design Group, a product of the active use of public service design. Third, a more specific evaluation system should be introduced to verify the effectiveness and effectiveness of public service design. Through this, it is expected that it will greatly contribute to reducing the error in policy delivery and realizing citizen-centered public services by utilizing design for various problems facing our society.

• Journal of fish pathology
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• v.26 no.2
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• pp.65-75
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• 2013

Population growth equation of scuticociliate Miamiensis avidus was obtained from the experimental results of in vitro culture condition to estimate the growth rate and carrying capacity from the growth equation. In addition, intraperitoneal infections into olive flounder Paralichthys olivaceus were carried out into 2 different conditions: different concentrations of M. avidus in same water temperature and same concentration of M. avidus in different water temperatures. Olive flounder mortality was threshold dependent with both the temperature and M. avidus density parameters. In this paper, we propose a mathematical model to study M. avidus growth in olive flounder based upon the interactions between parasite and host. The mathematical model was logistic growth differential equation (1.2). The parameters were found with Matlab program through the Levenberge-Marquardt method. In theorem, equilibrium values between the infected fish population and dead population could found. Our equilibrium points were a stable equilibrium and an unstable equilibrium. From the equation (1.6), it was possible to predict the amount of cumulative mortality of olive flounder along with the time after M. avidus infection.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.263-277
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• 2019

This study analyzed the current use of science-related test tools in affective area in Korean academic journals for the last 30 years since 1989 and the cases of modification of the original tools related to the tools. This provides practical information on the development and improvement of test tools in the future and offers the basis for developing valid test tools. The study was conducted in two stages. We analyzed the status of 88 domestic science education researches dealing with testing tools related affective characteristics and 57 domestic and foreign resource tools referenced by them. After that, we compared the characteristics of the five cases in which the original tool was revised and the concrete item correction examples. The results were analyzed as follows: topics that have emerged continuously or that have recently begun to appear in domestic research, the research situations according to their purpose and measurement methods used by the tool, and use state of original tools. The background and key points of revision were analyzed for the five tools, TOSRA, SAI, PISA items, STEBI-A/B, SMQ, whose revision process were disclosed. In addition, the changes of the items were analyzed by comparing the four test items with the questions before and after the revision. As a result of item analysis, item improvement was proceeding in the direction of enhancing readability, clarifying meaning, and changing items according to change of sub constructs. The implications of this study are as follows: notes on interpreting the results obtained from the tool with multiple mixed constructs, the possibility of the testing tool that broadens the horizon of the research, error recognition in the subjective self-report, and notes when applying test tools from other disciplines to science.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.289-295
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• 2014

Purpose : Cone Beam Computed Tomography(CBCT) in Image Guided Radiation Therapy(IGRT), Set-up error can be reduced but exposure dose of the patient due to CBCT will increase. Through this study, we are to evaluate by making a scenario with the implementation period of CBCT as every other day. Materials and Methods : Of prostate cancer patients, 9 patients who got a Intensity Modulated Radiation Therapy(IMRT) with CBCT in IGRT were analyzed. Based on values corrected by analyzing set-up error by using CBCT every day during actual treatment, we created a scenario that conducts CBCT every other day. After applying set-up error values of the day not performing CBCT in the scenario to the treatment planning system(Pinnacle 9.2, Philips, USA) by moving them from the treatment iso-center during actual treatment, we established re-treatment plan under the same conditions as actual treatment. Based on this, the dose distribution of normal organs and Planning Target Volume(PTV) was compared and analyzed. Results : In the scenario that performs CBCT every other day based on set-up error values when conducting CBCT every day, average X-axis : $0.2{\pm}0.73mm$, Y-axis : $0.1{\pm}0.58mm$, Z-axis : $-1.3{\pm}1.17mm$ difference was shown. This was applied to the treatment planning to establish re-treatment plan and dose distribution was evaluated and as a result, Dmean : -0.17 Gy, D99% : -0.71 Gy of PTV difference was shown in comparison with the result obtained when carrying out CBCT every day. As for normal organs, V66 : 1.55% of rectal wall, V66 : -0.76% of bladder difference was shown. Conclusion : In case of a CBCT perform every other day could reduce exposure dose and additional treatment time. And it is thought to be able to consider the application depending on the condition of the patient because the difference in the dose distribution of normal organs, PTV is not large.

• Progress in Medical Physics
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• v.10 no.2
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• pp.63-71
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• 1999

For the purpose of utilization in 3-D conformal radiotherapy and whole body radiosurgery, the Whole Body 3-Dimensional Topographic Radiation Therapy System has been developed. Whole body frame was constructed in order to be installed on the couch. Radiopaque catheters were engraved on it for the dedicated coordinate system and a MeV-Green immobilizer was used for the patient setup by the help of side panels and plastic rods. By designing and constructing the whole body frame in this way, geometrical limitation to the gantry rotation in 3-D conformal radiotherapy could be minimized and problem which radiation transmission may be altered in particular incident angles was solved. By analyzing CT images containing information of patient setup with respect to the whole body frame, localization and coordination of the target is performed so that patient setup error may be eliminated between simulation and treatment. For the verification of setup, the change of patient positioning is detected and adjusted in order to minimize the setup error by means of comparison of the body outlines using 3 CCTV cameras. To enhance efficiency of treatment procedure, this work can be done in real time by watching the change of patient setup through the monitor. The method of image subtraction in IDL (Interactive Data Language) was used to visualize the change of patient setup. Rotating X-ray system was constructed for detecting target movement due to internal organ motion. Landmark screws were implanted either on the bones around target or inside target, and variation of target location with respect to markers may be visualized in order to minimize internal setup error through the anterior and the lateral image information taken from rotating X-ray system. For CT simulation, simulation software was developed using IDL on GUI(Graphic User Interface) basis for PC and includes functions of graphic handling, editing and data acquisition of images of internal organs as well as target for the preparation of treatment planning.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.186-192
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry. In this study, previous algorithm for estimation of transmission dose was modified for use in cases with tissue deficit. Materials and Methods : The beam data was measured with flat solid phantom in various conditions of tissue deficit. New algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. The algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients using multiple sheets of solid phantoms. Results : The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ${\pm}1.0\%$ in most situations and within ${\pm}3.0\%$ in experimental settings with irregular contours mimicking breast cancer treatment set-up. Conclusion : Developed algorithm could accurately reflect the effect of tissue deficit and irregularly shaped body contour on transmission dosimetry.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.99-106
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• 2007

Purpose: The patient's position and anatomy during the treatment course little bit varies to some extend due to setup uncertainties and organ motions. These factors could affected to not only the dose coverage of the gross tumor but over dosage of normal tissue. Setup uncertainties and organ motions can be minimized by precise patient positioning and rigid immobilization device but some anatomical site such as prostate, the internal organ motion due to physiological processes are challenge. In planning procedure, the clinical target volume is a little bit enlarged to create a planning target volume that accounts for setup uncertainties and organ motion as well. These uncertainties lead to differences between the calculated dose by treatment planning system and the actually delivered dose. The purpose of this study was to evaluate the differences of interfractional displacement of organ and GTV based on the tomoimages. Materials and Methods: Over the course of 3 months, 3 patients, those who has applied rectal balloon, treated for prostatic cancer patient's tomoimage were studied. During the treatment sessions 26 tomoimages per patient, Total 76 tomoimages were collected. Tomoimage had been taken everyday after initial setup with lead marker attached on the patient's skin center to comparing with C-T simulation images. Tomoimage was taken after rectal balloon inflated with 60 cc of air for prostate gland immobilization for daily treatment just before treatment and it was used routinely in each case. The intrarectal balloon was inserted to a depth of 6 cm from the anal verge. MVCT image was taken with 5 mm slice thickness after the intrarectal balloon in place and inflated. For this study, lead balls are used to guide the registration between the MVCT and CT simulation images. There are three image fusion methods in the tomotherapy, bone technique, bone/tissue technique, and full image technique. We used all this 3 methods to analysis the setup errors. Initially, image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours and then the radiation therapist registered the MVCT images with the CT simulation images based on the bone based, rectal balloon based and GTV based respectively and registered image was compared with each others. The average and standard deviation of each X, Y, Z and rotation from the initial planning center was calculated for each patient. The image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours. Results: There was a significant difference in the mean variations of the rectal balloon among the methods. Statistical results based on the bone fusion shows that maximum x-direction shift was 8 mm and 4.2 mm to the y-direction. It was statistically significant (P=<0.0001) in balloon based fusion, maximum X and Y shift was 6 mm, 16mm respectively. One patient's result was more than 16 mm shift and that was derived from the rectal expansions due to the bowl gas and stool. GTV based fusion results ranging from 2.7 to 6.6 mm to the x-direction and 4.3$\sim$7.8 mm to the y-direction respectively. We have checked rotational error in this study but there are no significant differences among fusion methods and the result was 0.37$\pm$0.36 in bone based fusion and 0.34$\pm$0.38 in GTV based fusion.

• The Korean Journal of Nuclear Medicine
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• v.32 no.5
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• pp.414-424
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• 1998

Purpose: Cross-modality coregistration of positron emission tomography (PET) and magnetic resonance imaging (MR) could enhance the clinical information. In this study we propose a refined technique to improve the robustness of registration, and to implement more realistic visualization of the coregistered images. Materials and Methods: Using the sinogram of PET emission scan, we extracted the robust head boundary and used boundary-enhanced PET to coregister PET with MR. The pixels having 10% of maximum pixel value were considered as the boundary of sinogram. Boundary pixel values were exchanged with maximum value of sinogram. One hundred eighty boundary points were extracted at intervals of about 2 degree using simple threshold method from each slice of MR images. Best affined transformation between the two point sets was performed using least square fitting which should minimize the sum of Euclidean distance between the point sets. We reduced calculation time using pre-defined distance map. Finally we developed an automatic coregistration program using this boundary detection and surface matching technique. We designed a new weighted normalization technique to display the coregistered PET and MR images simultaneously. Results: Using our newly developed method, robust extraction of head boundary was possible and spatial registration was successfully performed. Mean displacement error was less than 2.0 mm. In visualization of coregistered images using weighted normalization method, structures shown in MR image could be realistically represented. Conclusion: Our refined technique could practically enhance the performance of automated three dimensional coregistration.