• Progress in Medical Physics
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• v.15 no.4
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• pp.186-191
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• 2004

The periodic Quality Assurance (QA) of each radiation treatment related equipments is important one, but quality assurance of the radiation treatment planning system (RTPS) is still not sufficient rather than other related equipments in clinics. Therefore, this study will present and test the periodic QA program to compare, evaluation the efficiency of the treatment planning systems. This QA program is divided to terms for the input, output devices and dosimetric data and categorized to the weekly, monthly, yearly and non-periodically with respect to the job time, frequency of error, priority of importance. CT images of the water equivalent solid phantom with a heterogeneity condition are input into the RTPS to proceed the test. The actual measurement data are obtained by using the ion chamber for the 6 MV, 10 MV photon beam, then compared a calculation data with a measurement data to evaluate the accuracy of the RTPS. Most of results for the accuracy of geometry and beam data are agreed within the error criteria which is recommended from the various advanced country and related societies. This result can be applied to the periodic QA program to improve the treatment outcome as a proper model in Korea and used to evaluate the accuracy of the RTPS.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.2
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• pp.69-81
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• 2011

The soil moisture data of the National Aeronautics and Space Administration(NASA) and the Vrije Universiteit Amsterdam(VUA) in collaboration with NASA, retrieved from Advanced Microwave Scanning Radiometer-Earth observing system(AMSR-E) brightness temperature, were collected to evaluate the applicability of the remote sensed soil moisture in South Korea. The averages of the soil moisture by in-situ sensors, by NASA and by VUA-NASA are approximately 0.218, 0.119, and $0.402m^3/m^3$, respectively. This indicates that the soil moisture of NASA was underestimated and that of VUA-NASA was overestimated. The soil moisture products of VUA-NASA showed a better relationship with the in-situ data than that of NASA data. However, there are still limitations of C-band soil moisture measurements. To improve the applicability of satellite soil moisture measurements, bias correction and other post processings are essential using in-situ soil moisture measurements at various surface conditions.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.109-119
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• 2011

The virtual reality (VR) technology has been used as the application of architectural presentation or simulation tool in the field of industry. The high immersion and intuitive visual information are the great merits of design evaluation or environmental simulation when we are using the virtual environments. But the distortion of distance perception in VR is still a big problem when the accuracy of distance presentation is strictly required. For example, distance estimation is especially important when the virtual environments are applied to the presentational tool for evaluation the space design or planning in the field of architecture. If there are some perception error between the built space in real and represented space in virtual, the accurate design evaluation or modification of design is hard to be carried out during the design development stage. In this paper, we have carried out some experiments about distance estimation in the immersive virtual environments to verify the factors and their influence. We made a hypothesis that the lack of the information for the user in VR causes the different distance estimation from the real world because users are usually comfortable with moving fast and long distance in VR environments compared with moving slow and short distance in real space. So, we carried out basic experiment to prove our hypothesis that the lack of information makes subjects estimate the distance of walking in VR shorter compared with the same distance in real. Also, among the factors that probably affect the distance estimation in VR, we have verified the influence of the image resolution. The influence of resolution degradation of image on the distance estimation was verified with the condition of static and dynamic images. The results showed that the resolution has deep relation with the distance estimation. For example, the subject underestimated the distance at the lower resolution condition. We also found the methods of the making the lower resolution image could affect on the visual perception of subjects.

• Advances in nano research
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• v.1 no.3
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• pp.159-169
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• 2013

A preparation method for gadolinium compound (GdC) nanoparticles coated with silica ($GdC/SiO_2$) is proposed. GdC nanoparticles were prepared with a homogeneous precipitation method at $80^{\circ}C$ using $1.0{\times}10^{-3}$ M $Gd(NO_3)_3$, 0.5 M urea and $0-3.0{\times}10^{-4}$ M ethylenediarinnetetraacetic acid disodium salt dihydrate (ETDA) in water. As a result of preparation at various EDTA concentrations, GdC nanoparticles with a size as small as $40.5{\pm}6.2$ nm, which were colloidally stable, were prepared at an EDTA concentration of $2.0{\times}10^{-4}$ M. Silica-coating of the GdC nanoparticles was performed by a St$\ddot{o}$ber method at $35^{\circ}C$ using $1.0-10.0{\times}10^{-3}$ M tetraethylorthosilicate (TEOS), 11 M $H_2O$ and $1.5{\times}10^{-3}$ M NaOH in ethanol in the presence of $1.0{\times}10^{-3}$ M GdC nanoparticles. Performance of preparation at various TEOS concentrations resulted in production of $GdC/SiO_2$ particles with an average size of $106.1{\pm}11.2$ nm at a TEOS concentration of $5.0{\times}10^{-3}$ M. The gadolinium (Gd) concentration of $1.0{\times}10^{-3}$ M in the as-prepared $GdC/SiO_2$ particle colloid solution was increased up to a Gd concentration of 0.2 M by concentrating with centrifugation. The core-shell structure of $GdC/SiO_2$ particles was undamaged, and the colloid solution was still colloidally stable, even after the concentrating process. The concentrated $GdC/SiO_2$ colloid solution showed images of X-ray and magnetic resonance with contrast as high as commercial Gd complex contrast agents.

• Cross-Cultural Studies
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• v.37
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• pp.31-49
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• 2014

Peking has peculiar features as capital city, and has gone through various transformations, with its name changed from Peking to Peiping to Peking. Even when it did not serve as a capital city, it still played an unrivaled role in cultural aspects. Laoshe, a great writer of 'Peking flavour' literature, is famous for works full of cultural charms of Peking. In his works, which show the manners, norms, art, culture and optimistic life style of Peking, Peking culture is described as an extension of cultural traditions of Qiren. In addition, his critical view of reality is also expressed in the works. Linhaiyin's literary works show ordinary hutongs she experienced in the 1920s in Chengnan, the southern part of Peking, and the quiet and simple life of warm-hearted people living there. Her vague memories of Peking, along with her nostalgia for the city, let her describe the city with recreated happy memories of it instead of the harsh critical view. Her works express the city in her recreated memory full of hope, with her dark memories of the city being glossed over. As seen above, Laoshe realistically described the tragic and difficult life of low class people in hutongs of Peking as well as lower middle class people of the city. Meanwhile, in ChengnanJiushi, Linhaiyin expresses the daily routine and ordinary life of people in Peking from the perspective of middle class people. In addition, she showed the sympathetic view of middle class citizens towards their low-class neighbors. In Peking Menghualu, Wangdewei mentioned that the 'castle of memory' which old Peking people in Taiwan tried to establish fills an important gap for the continuity of Peking cultural history and cultural imagination. This indicates that the 'Peking castle of memories,' which Linhaiyin, a Taiwanese writer well known for 'Peking flavour,' has established plays a big role in filling part of such gap. ChengnanJiushi, Wuyigong's film based on Linhaiyin's novel of the same title, also describes the daily sceneries and culture of the southern Peking in the 1920s, which both Taiwanese and Chinese people miss, through sophisticated images with 'profound yearning tinted with calm sadness', accomplishing an artistic achievement different from that of the novel.

• Korean Journal of Remote Sensing
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• v.21 no.4
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• pp.341-369
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• 2005

Hyperspectral images have emerged as a new and promising remote sensing data that can overcome the limitations of existing optical image data. This study was designed to provide a comprehensive review on definition, data processing methods, and applications of hyperspectral data. Various types of airborne, spaceborne, and field hyperspectral image sensors were surveyed from the available literatures and internet search. To understand the current status of hyperspectral remote sensing technology and research development, we collected several hundreds research papers from international journals (IEEE Transactions on Geoscience and Remote Sensing, International Journal of Remote Sensing, Remote Sensing of Environment and AVIRIS Workshop Proceedings), and categorized them by sensor types, data processing techniques, and applications. Although several hyperspectral sensors have been developing, AVIRIS has been a primary data source that the most hyperspectral remote sensing researches were relied on. Since hyperspectral data have very large data volume with many spectral bands, several data processing techniques that are particularly oriented to hyperspectral data have been developed. Although atmospheric correction, spectral mixture analysis, and spectral feature extraction are among those processing techniques, they are still in experimental stage and need further refinement until the fully operational adaptation. Geology and mineral exploration were major application in early stage of hyperspectral sensing because of the distinct spectral features of rock and minerals that could be easily observed with hyperspectral data. The applications of hyperspectral sensing have been expanding to vegetation, water resources, and military areas where the multispectral sensing was not very effective to extract necessary information.

• Journal of the Korean Society of Child Welfare
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• no.26
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• pp.7-30
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• 2008

The survival rate of children with cancer has increased significantly from less than 30% in 1960s to 75% during the recent years with the development of modern medical technologies. As a result, the cancer of children today is no longer classified as incurable diseases. Rather, it is recognized as a chronic illness. However, children with cancer are still suffering from physical and psychosocial ailments caused by long-term hospitalization. In particular, teenagers are more likely to be affected by these problems because of interests on one's appearance and peer relationships This study investigated the relationship of the level of body distortion and disease adjustment of children with cancer, and how demographic factors, disease factors, and the level of body distortion affect disease adjustment. Data were collected between October 22, 2007 and November 16, 2007 and the total respondents consisted of 82 children, ages 10 to 18. SPSS 12.0 with descriptive statistics, t-test, correlation and multiple regression were used for data analysis. The results showed that the factors which influence the disease adjustment of children with cancer were age, school enrollment, and the level of body distortion. The result of this study has major implications for the government to provide support for children with cancer to stay in school. Additionally, programs that assist children to build positive body images need to be developed in accordance with their ages and psychosocial characteristics.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.10
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• pp.421-428
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• 2021

The High Efficiency Image File Format (HEIF) is an MPEG-developed image format that utilizes the video codec H.265 to store still screens in a single image format. The iPhone has been using HEIF since 2017, and Android devices such as the Galaxy S10 have also supported the format since 2019. The format can provide images with good compression rates, but it has a complex internal structure and lacks significant compatibility between devices and software, making it not popular to replace commonly used JPEG (or JPG) files. However, despite the fact that many devices are already using HEIF, digital forensics research regarding it is lacking. This means that we can be exposed to the risk of missing potential evidence due to insufficient understanding of the information contained inside the file during digital forensics investigations. Therefore, in this paper, we analyze the HEIF formatted photo file taken on the iPhone and the motion photo file taken on the Galaxy to find out the information and features contained inside the file. We also investigate whether or not the software we tested support HEIF and present the requirement of forensic tools to analyze HEIF.

• Journal of Korean Theatre Studies Association
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• no.48
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• pp.51-84
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• 2012

In Korea, historical plays took an epoch-making turn from the previous historical plays in terms of approaches to topic and material and methods of rewriting history in the 1990s. Historical plays became dehistoricized with individual, everyday life, and faction emerging as major codes of historical plays according to mistrust in history and grand narrative as the original and disappearance of trust in the growth and totality of history. A new trend became dominant of presenting fictionality prominent instead of reproduction of history and freely playing with history outside the context. While modern historical plays were subject to the content of history, post-modern historical plays sought after new history writing to tell a new story on history within a framework of fiction. Focusing on some of the trends in post-modern historical plays since the 1990s, which include play with history, daily life-style history writing, and reproduction patterns of colonial modernity, this study examined the goals, representations, and text strategies of new history writing in three historical plays, Generation After Generation(2000) by Park Geunhyung, The Mercenaries(2000) by Park Sujin, and Chosun Detective Hong Yunshik(2007) by Sung Giwoong. In Generation After Generation, the author adopts a plot of starting with the present and tracing back to the past, breaking down the myth of racially homogeneous nation. At the same time, he discloses that the colonial history is not just by the oppressive force of Japan but also by the voluntary cooperation of Korean people. That is, we are also accountable for the colonial history of the nation. The Mercenaries contrasts the independence movement during the colonial period against the modern history developed after Liberation, thus highlighting the still continuing coloniality, namely post-colonial present. The past is presented as the "phantom of history" making its appearance according to the request of the present hoping for salvation. The author politicizes history and grants political wishes to history by summoning the history by personal memories such as fictional diaries and letters with Messiah-like images opposed to the present of collapse and catastrophe. In Chosun Detective Hong Yunshik, the author makes an attempt at the microscopic reproduction of daily life by approaching the 1930s as the modern period when capitalist daily life started to take root. The lists of signs comprising daily life in colonial Gyeongseong are divided between civilization and savagery and between modern and premodern. With the progress of narrative, however, they become mixed together and reversed in the representation system in which the latter overwhelms the former.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1161-1175
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• 2018

An unexpected event could be easily followed by a large secondary accident due to the limitation in sight of drivers in road tunnels. Therefore, a series of automated incident detection systems have been under operation, which, however, appear in very low detection rates due to very low image qualities on CCTVs in tunnels. In order to overcome that limit, deep learning based tunnel incident detection system was developed, which already showed high detection rates in November of 2017. However, since the object detection process could deal with only still images, moving direction and speed of moving vehicles could not be identified. Furthermore it was hard to detect stopping and reverse the status of moving vehicles. Therefore, apart from the object detection, an object tracking method has been introduced and combined with the detection algorithm to track the moving vehicles. Also, stopping-reverse discrimination algorithm was proposed, thereby implementing into the combined incident detection processes. Each performance on detection of stopping, reverse driving and fire incident state were evaluated with showing 100% detection rate. But the detection for 'person' object appears relatively low success rate to 78.5%. Nevertheless, it is believed that the enlarged richness of image big-data could dramatically enhance the detection capacity of the automatic incident detection system.