• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.612-618
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• 2016

The aim of this study is to investigate the effects of stray light originating from the blue-light blocking lens on the quality of the image. After designing the ideal spectacle lens, anti-reflection spectacle lens without internal reflection, anti-reflection spectacle lens with internal reflection, and blue-light blocking lens with internal reflection, the light intensity distribution and stray light distribution were derived. The designed spectacle lenses are meniscus lenses with a refractive power of 0.00 D, refractive index of 1.56, and a radius of 155.15 mm. The peaks of reflectance of the 4 types of blue-light blocking lenses are in the range between 430 nm and 440 nm, and their reflectances are 5%, 10%, 15%, and 20%, respectively. According to the analysis results, as the reflectance of the blue-light blocking lens increases, the light intensity in the center of the lens decreases and the intensity of the stray light in the center-periphery and periphery of the lens increases. This trend appeared to intensify with increasing reflectance of the blue-light blocking lenses. Because the increase in the reflectance of the blue-light blocking lens degrades the quality of the image by increasing the intensity of the stray light in the center-periphery and periphery of the lens, its reflectance needs to be adjusted by varying the blue-light blocking ratio and the luminous transmittance, in order to diminish the level of visual discomfort.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.19-27
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• 2010

The purpose of this study is to evaluate urban parks and green spaces within the public service framework by identifying priority elements. This study surveyed 455 residents from 80 dongs(neighborhoods), of 5 Gu(districts) districts in Daejeon. The results were as follows. Regarding the evaluation of urban parks as a public service, the average survey score, of all 46 questions, was distributed from 2.46 to 3.54(Likert 5 point scale). Interesting findings can be observed in that most of the survey participants gave high scores to Daejon's natural green environments and geographical traits. That is, Daejon residents perceived their urban nature spaces as a natural geographical environment rather than a public service provided by their local government. Therefore, it seems necessary for the local government, by and large, to improve urban parks and urban green space programs. The low scoring items were 'citizen's participation'(mean 2.46), 'acceptance of complaints, comments, and improvement proposals'(mean 2.54), 'citizen's respect', 'inclusive design' (for the physically challenged-mean 2.55), 'diverse programs and activities in the urban park'(mean 2.55) and 'implementation of revision proposals by citizens'(mean 2.61). These results indicate that citizen participation in planning and opinion sharing is needed to build public services that are satisfactory to users. To evaluate the park and green space from the viewpoint of public services is a useful method with a new point of view. In accordance with this study, the factor of 'supply decision maker' is a statistically meaningful variable of resident satisfaction while earlier studies on the satisfaction studies of physical environment, hardly discovered variables on 'supply decision maker', 'acceptance of resident opinions', and 'information usage'. Responding to or taking positive action according to significant factors, such as the findings of this study, can expand the role of public officials to exert a more positive influence on urban parks and green spaces.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.165-171
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• 2002

Purpose : In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. Materials and Method : A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetrie image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was peformed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. Results : CSI in the supine position was successfully peformed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The differences between the DRRs and the portal films were less than 3 mm in the vertebral contour. Conclusion : CSI in the supine position is feasible in patients who cannot lie on prone position, such as pediatric patienta under the age of 4 years, patients with a poor general condition, or patients with a tracheostomy.

• Progress in Medical Physics
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• v.14 no.2
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• pp.90-98
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• 2003

Purpose : A new virtual simulation technique for craniospinal irradiation (CSI) that uses a CT-simulator was developed to improve the accuracy of field and shielding placement as well as patient positioning. Materials and Methods : A CT simulator (CT-SIM) and a 3-D conformal radiation treatment planning system (3D-CRT) were used to develop CSI. The head and neck were immobilized with a thermoplastic mask while the rest of the body was immobilized with a Vac-Loc. A volumetric image was then obtained with the CT simulator. In order to improve the reproducibility of the setup, datum lines and points were marked on the head and body. Virtual fluoroscopy was performed with the removal of visual obstacles, such as the treatment table or immobilization devices. After virtual simulation, the treatment isocenters of each field were marked on the body and on the immobilization devices at the conventional simulation room. Each treatment fields was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR) and digitally composited radiography (DCR) images from virtual simulation. Port verification films from the first treatment were also compared with the DRR/DCR images for geometric verification. Results : We successfully performed virtual simulations on 11 CSI patients by CT-SIM. It took less than 20 minutes to affix the immobilization devices and to obtain the volumetric images of the entire body. In the absence of the patient, virtual simulation of all fields took 20 min. The DRRs were in agreement with simulation films to within 5 mm. This not only reducee inconveniences to the patients, but also eliminated position-shift variables attendant during the long conventional simulation process. In addition, by obtaining CT volumetric image, critical organs, such as the eyes and the spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. Differences between the DRRs and the portal films were less than 3 m in the vertebral contour. Conclusion : Our analysis showed that CT simulation of craniospinal fields was accurate. In addition, CT simulation reduced the duration of the patient's immobility. During the planning process. This technique can improve accuracy in field placement and shielding by using three-dimensional CT-aided localization of critical and target structures. Overall, it has improved staff efficiency and resource utilization by standard protocol for craniospinal irradiation.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.1
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• pp.1-11
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• 2013

In nature, to change the consciousness of those who wish to pursue something new, the road is turning function-oriented 'Walking Path' into purpose-oriented 'Walking Trails'. Though 'Walking Trails' is a long linear journey that leads people to see, to feel and to experience while walking on the trail, but considering on the landscape of trails when selecting routes is lacking. Landscapes, which are felt and perceived while walking on the trail, provide a purpose, and can be an important factor to improve visitor satisfaction. However, the study is insufficient in terms of landscape of trails. Therefore, it is the purpose of this study to find ways to help improving visitors' satisfaction in selecting routes, by analyzing the images and preferences of trails landscapes that are visually perceived, by analyzing the correlation between visitors' satisfaction and them. For this study, landscape assessment was carried out after selecting representative landscape photos of BukhansanDulegil 13 sections and landscape images adjectives for landscape assessment. Through the assessment, analyze landscape images of each section, landscape images factors affecting a wish to walk and landscape preferences, relationship between visitors' satisfaction and them. 'Refreshing' image was higher on the path with many trees and less artificial elements; 'urban' image was higher on the path with artificial elements. 'A wish to walk' and 'landscape preference' was higher on the path showed 'refreshing' and 'pastoral' image with many natural elements. Factors affecting 'a wish to walk' were "refreshing-unpleasant", "impressive-ordinary", factors affecting 'landscape preference' were "refreshing-unpleasant", "comfortable-uncomfortable". In addition, landscape preference was found to have a high correlation with visitors' satisfaction.

• Archives of design research
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• v.17 no.4
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• pp.191-200
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• 2004

The health of feet is connected with individual's health and affects a man's activity. Shoes need to be designed to protect feet and to absorb the impact of land. Thus, design, comfort and economical efficiency are important factors of shoes. Consumers can choose suitable shoes for their feet in off-line shopping. However, in on-line shopping, because they can not wear shoes, compare to the off-line shopping, there are many problems in internet shopping. First, consumers can get limited information of shoes because they must search information of purchase without other's help. Second, because consumers can not get important information such as design, size and a comfort of wearing, they can not make a careful decision. Above these, the solution of user-oriented internet shopping is development of new type of prototype which is accessible to user and to offer visual information through 3D virtual reality.

• Smart Media Journal
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• v.8 no.3
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• pp.23-30
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• 2019

With the popularization of the Internet and smartphone uses, people in the modern era are living in a multi-channel environment in which they access the information system freely through various methods and media. In the process of utilizing such services, users must authenticate themselves, the typical of which is ID & password authentication. It is considered the most convenient method as it can be authenticated only through the keyboard after remembering its own credentials. On the other hand, modern web services only allow passwords to be set with high complexity by different combinations. Passwords consisting of these complex strings also increase proportionally, since the more services users want to use, the more user authentication information they need to remember is recommended periodically to prevent personal information leakage. It is difficult for the blind, the disabled, or the elderly to remember the authentication information of users with such high entropy values and to use it through keyboard input. Therefore, this paper proposes a user authentication method using Google Assistant, MFCC and DTW algorithms and speaker authentication to provide the handicapped users with an easy user authentication method in the login process.

• Journal of Communication Design
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• v.65
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• pp.530-538
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• 2018

Recently, museums are attracting the attention of visitors and society. However, research on museum interpretation conducted at domestic and foreign is relatively limited. The plan design of the museum commentary system was mainly based on the perspective of the experts, and most of them do not reflect the desire of the visitors. This study focused on visitors' experience of using museum Interpretation system. Through analyzing the effect of the Interpretation system of the museum that the visitor feels, we examined whether the Interpretation system of the museum meets the cultural needs of the visitors and identified the problems and deficiencies in the system. After that, the problems were rearranged and suggested the main elements of the commentary system of the museum finally, so as to help improve the museum commentary system and the educational function.In the first part of the study, the four major explanatory methods existing in the museum were confirmed. After that, we conducted in - depth interviews on four types of commentary methods and collected existing problems and deficiencies. The results of the type analysis were grouped into 14 types and the questionnaire was used to conduct a general survey on 14 problems. In this study, the user 's discomfort and problems were identified in the museum Interpretation system, and based on this, five key elements necessary for the museum Interpretation system were derived. Among them, inhalation is the weakest element in the museum commentary system, and future research will be conducted on how to apply each factor. I hope that you will be a reference material when you carry out research on the optimization of the Interpretation system of the museum and the improvement of the Interpretation experience.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.5
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• pp.257-262
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• 2006

Purpose: The standard protocol using large volume of oral contrast media may cause gastrointestinal discomfort and contrast-related artifacts in PET/CT. The aim of this study was to evaluate the usefulness of low dose oral contrast in $^{18}F-FDG$ PET/CT. Materials and Methods: We retrospectively reviewed the whole-body PET/CT images in a total of 435 patients. About 200 ml of oval contrast agent (barium sulfate) was administered immediately before injection of $^{18}F-FDG$. The FDG uptake of intestines was analyzed by visual and semi- quantitative method on transaxial, coronal and saggital planes. Results: Seventy (16%, 113 sites) of 435 images showed high FDG uptake (peak SUV > 4); 50 (74%, 84 sites) with diffuse and 20 (15%, 29 sites) with focal uptake. The most commonly delivered site of oral contrast media was small bowel (n=27, 39%). On PET/CT images, FDG uptake coexisted with oral contrast media in 26 patients (54%, 38 sites) with diffuse pattern and 9 (45%, 9 sites) with focal pattern, and by sites, those were 38 (45%) and 9 (31%), respectively. In small bowel regions, the proportion of coexistence reached as high as 61% (29/47 sites). A visual analysis of available non-attenuation corrected PET images of 27 matched regions revealed no contrast-related artifact. Conclusion: We concluded that the application of low dose contrast media could be helpful in the evaluation of abdominal uptake in the FDG PET/CT image.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.347-356
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• 2013

Purpose: To evaluate the visual acuity and visual performance after implantation of a aspheric multifocal (ReSTOR$^{(R)}$ SN6AD3) intraocular lens (IOL). Methods: Nineteen cataract patients (30 eyes) implanted with an aspheric multifocal IOL (ReSTOR$^{(R)}$ SN6AD3) either unilaterally or bilaterally were participated. Visual acuity (VA) and objective optical performance were evaluated at the time of preoperation, 1 week, 1 month, and 3 month after operation. At 3 month of post-operation, objective visual performance were measured and compared with the 38 eyes of 20 age-matched normal control. Distance VA was measured by using the ETDRS LCD chart and intermediate and near visual acuity were measured using Jaeger chart. Objective visual performance was assessed preoperatively and 1 week, 1 month and 3 month postoperatively using a double-pass system (Optical Quality Analysis System) with a 4-mm pupil diameter, the OSI (objective scatter index), MTF (modulation transfer function) cut off and strehl ratio. At 3 month of post-operation, visual acuity and visual performance compared with age matched normal control. Results: The uncorrected distance VA, OSI, MTF cut off and strehl ratio were significantly improved (p<0.05) until 1 month postoperatively. Visual performance of MTF cut off and strehl ratio after 3 month of operation were significantly improved compared to the normal control (p=0.063, p=0.103 respectively), however, OSI was higher than normal control. Patients implanted with aspheric multifocal IOL were satisfied with distance and near VA however, were unsatisfied with intermediate VA and reported glare and halos. Conclusions: The visual performance reaches to a stable condition in 1 month of implantation of aspheric multifocal IOL and improved to the level of age-mated normal patients. Also patients were satisfied with their quality of vision, however, intermediate VA, glare and halos were reported as complications.