• Progress in Medical Physics
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• v.25 no.2
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• pp.72-78
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• 2014

The aim of the study is to test a hypothesis that quasi-breath-hold (QBH) biofeedback improves the residual respiratory motion management in gated 3D thoracic MR imaging, reducing respiratory motion artifacts with insignificant acquisition time alteration. To test the hypothesis five healthy human subjects underwent two gated MR imaging studies based on a T2 weighted SPACE MR pulse sequence using a respiratory navigator of a 3T Siemens MRI: one under free breathing and the other under QBH biofeedback breathing. The QBH biofeedback system utilized the external marker position on the abdomen obtained with an RPM system (Real-time Position Management, Varian) to audio-visually guide a human subject for 2s breath-hold at 90% exhalation position in each respiratory cycle. The improvement in the upper liver breath-hold motion reproducibility within the gating window using the QBH biofeedback system has been assessed for a group of volunteers. We assessed the residual respiratory motion management within the gating window and respiratory motion artifacts in 3D thoracic MRI both with/without QBH biofeedback. In addition, the RMSE (root mean square error) of abdominal displacement has been investigated. The QBH biofeedback reduced the residual upper liver motion within the gating window during MR acquisitions (~6 minutes) compared to that for free breathing, resulting in the reduction of respiratory motion artifacts in lung and liver of gated 3D thoracic MR images. The abdominal motion reduction in the gated window was consistent with the residual motion reduction of the diaphragm with QBH biofeedback. Consequently, average RMSE (root mean square error) of abdominal displacement obtained from the RPM has been also reduced from 2.0 mm of free breathing to 0.7 mm of QBH biofeedback breathing over the entire cycle (67% reduction, p-value=0.02) and from 1.7 mm of free breathing to 0.7 mm of QBH biofeedback breathing in the gated window (58% reduction, p-value=0.14). The average baseline drift obtained using a linear fit was reduced from 5.5 mm/min with free breathing to 0.6 mm/min (89% reduction, p-value=0.017) with QBH biofeedback. The study demonstrated that the QBH biofeedback improved the upper liver breath-hold motion reproducibility during the gated 3D thoracic MR imaging. This system can provide clinically applicable motion management of the internal anatomy for gated medical imaging as well as gated radiotherapy.

• Investigative Magnetic Resonance Imaging
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• v.16 no.1
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• pp.67-75
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• 2012

Purpose : We studied enhanced method to view the vessels in the brain using Magnetic Resonance Angiography (MRA). Noticing that Maximum Intensity Projection (MIP) image is often used to evaluate the arteries of the neck and brain, we propose a new method for view brain vessels to stereo image in 3D space with more superior and more correct compared with conventional method. Materials and Methods: We use 3T Siemens Tim Trio MRI scanner with 4 channel head coil and get a 3D MRA brain data by fixing volunteers head and radiating Phase Contrast pulse sequence. MRA brain data is 3D rotated according to the view angle of each eyes. Optimal view angle (projection angle) is determined by the distance between eye and center of the data. Newly acquired MRA data are projected along with the projection line and display only the highest values. Each left and right view MIP image is integrated through anaglyph imaging method and optimal stereoscopic MIP image is acquired. Results: Result image shows that proposed method let enable to view MIP image at any direction of MRA data that is impossible to the conventional method. Moreover, considering disparity and distance from viewer to center of MRA data at spherical coordinates, we can get more realistic stereo image. In conclusion, we can get optimal stereoscopic images according to the position that viewers want to see and distance between viewer and MRA data. Conclusion: Proposed method overcome problems of conventional method that shows only specific projected image (z-axis projection) and give optimal depth information by converting mono MIP image to stereoscopic image considering viewers position. And can display any view of MRA data at spherical coordinates. If the optimization algorithm and parallel processing is applied, it may give useful medical information for diagnosis and treatment planning in real-time.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.108-121
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• 2016

The purpose of this study is to explore the issues and implications for landscape design education in Korean landscape architecture by analyzing the National Exhibition of Korean Landscape Architecture(NEKLA). This study analyzed the suggested topics and selected site as well as the commentary that appeared in the NEKLA's award-winning book published from 2004 to 2014. Results of the study are as follows: First, topics of NEKLA are not only competition guidelines but related to exploring new area and role of Korean landscape architecture. Second, most dealing with site is 'industrial heritage and regeneration space' and 'green infrastructure'. In more recent years, a larger variety of sites were addressed. Third, site locations are concentrated in metropolitan areas, and awards and participation of the non-metropolitan universities was very low. Fourth, seven criteria can be applied in a general landscape design competition such as 'newness of the concept(idea)', 'logicality of the design process', 'selection of site fidelity of analysis(interpretation)', 'presentation and completion of the master plan', 'consistency with the theme', 'linkage of concepts and results' and 'feasibility'. The evaluation criteria are increasing the sophistication of the design language to provide useful suggestions on how to find design education methods. Its implications are as follows: First, training is essential to derive innovative ideas, but it should avoid excessive concept-oriented education. Second, design education may include instruction on how to define the problems related with the site. Third, more emphasis on design logic is essential to transform the innovative concept to actual results. Fourth, 'slick images' unrelated to design should be suppressed. Fifth, practice is needed to solve the topics addressed in the design process of education. Sixth, 'feasibility' and 'creative thinking' are necessary to recognize a reciprocal relationship that is helpful to one another. This study uses direct quote commentary to minimize the subjectivity of the researcher and to trace issues of the contemporary landscape architecture more directly and vividly. This study is a record waiting for another review as meta-criticism. In this regard this study, the landscape architect of the next times will have a mean that historical records to review the current thinking of the landscape theory and design.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.5
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• pp.10-21
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• 2018

This study used text mining methodology to focus on the perceptions of the landscape embedded in text that users spontaneously uploaded to the "Taean Travel"blogpost. The study area is the Taean Coast National Park. Most of the places that are searched by 'Taean Travel' on the blog were located in the Taean Coast National Park. We conducted a network analysis on the top three places and extracted keywords related to the landscape. Finally, using a centrality and cohesion analysis, we derived landscape perceptions and the major characteristics of those landscapes. As a result of the study, it was possible to identify the main tourist places in Taean, the individual landscape experience, and the landscape perception in specific places. There were three different types of landscape characteristics: atmosphere-related keywords, which appeared in Kkotji Beach, symbolic image-related keywords appeared in Sinduri Coastal Sand Dune, and landscape objects-related appeared in Manlipo Beach. It can be inferred that the characteristics of these three places are perceived differently. Kkotji Beach is recognized as a place to appreciate a view the sunset and is a base for the Taean Coast National Park's trekking course. Sinduri Coastal Sand Dune is recognized as a place with unusual scenery, and is an ecologically valuable space. Finally, Manlipo Beach is adjacent to the Chunlipo Arboretum, which is often visited by tourists, and the beach itself is recognized as a place with an impressive appearance. Social media data is very useful because it can enable analysis of various types of contents that are not from an expert's point of view. In this study, we used social media data to analyze various aspects of how people perceive and enjoy landscapes by integrating various content, such as landscape objects, images, and activities. However, because social media data may be amplified or distorted by users' memories and perceptions, field surveys are needed to verify the results of this study.

• Journal of radiological science and technology
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• v.31 no.2
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• pp.109-114
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• 2008

There is a standard shoulder oblique method (Grashey method) available to view the shoulder joint. This method projects AP view of the shoulder joint so that the Humerus head's subuxation or joint degeneration can be easily visualized. However, in this view, the patients, with supine or sitting or erect position, have to keep their body obliquely. Whereas, the patients who are not well or operated, usually feel very uncomfortable to keep their body in this position and hence, we need other persons' help and much efforts will be needed to get the good quality shoulder joint view. Therefore, we thought of examining a method which shows the joint well by angling the tube to Medio-Lateral direction and without keeping the patients' one side upward in supine position. For this study, total 15 subjects with no history of neurological or psychiatric illness, were recruited for examinations. They consisted of 9 males and 6 females. Statistic group analysis was performed with ANOVA test. Scores of the evaluation of the experts were $1.10{\pm}0.54$ at $25^{\circ}$, $2.50{\pm}0.50$ at 30^{\circ}$, $2.85{\pm}0.36$ at $35^{\circ}$ and $2.33{\pm}0.47$ at $40^{\circ}$, respectively, and they were significant(p<0.05, Table 1). Joint space of the Humerus head and Scapula were well distinguished at $35^{\circ}$, $30^{\circ}$ and $40^{\circ}$ with the almost same score. However, the degree of distortion at $40^{\circ}$ was more severe than that at $30^{\circ}$. Ultimately, $30-35^{\circ}$ views were shown to yield good quality shoulder oblique images. In conclusion, this method may be very useful for the patients who are uncomfortable and for the emergency patients. In order to get similar or comparable view, the same X-tube angle is recommended to be used before and after the operation. Therefore, we hope that this new angled method seems to be efficient.

• Cartoon and Animation Studies
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• s.40
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• pp.521-549
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• 2015

We recognize all objects by seeing. However, we are not sure that the things we see through our eyes are their essence. Here comes my question: What does it mean that humans see and recognize things? The things we see are images and so I consider recognizing an object as semiosis via our visual sensation and brain. That is because objects are defined not by their essence but as symbols we recognize. In the era of post-modernism art is a voluntary creative activity that creates a kind of spiritual value and plays an important role for appreciators who realize the fact to enjoy the life value. This paper focused on the art putting aesthetic value on humans' recognition and explored works of art in a visually perceptible way through semiosis. That is because art, an act of creating things, is symbolic and closely linked to semiotic system. Furthermore, derivative visual signs can be considered to be in line with the viewers' visual perception. If we interpreted by recognizing the works of art along with symbol, we can enjoy the works in depth through recognizing their color or shape. Therefore, I intended to discourse on color perception focusing on colors in order to analyze the relationship between art and symbol in the process of recognizing works of art. This paper looked into background of color recognition, status of colors and ways of expression for impressionist who painted with various colors and examined colors as a sensory language. In the process of interpreting art works by communication between the artist and viewers, the role of color is considered as visual symbol through the artist's experience, consciousness, emotions, and their senses. It can be interpreted the visual language through signification of the symbols when the colors are formed in works of art as a recognizable space. Therefore we expect to study in the Visual arts to be the colors symbolic analysis is extended to more effective communication tool.

• Cartoon and Animation Studies
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• s.44
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• pp.1-31
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• 2016

In this thesis, the movie with mise-en-scene established was compared with the peculiarity of the play that is the etymological source of the term to identify the peculiarity of mise-en-scene which was substituted into animation to find the peculiarity of mise-en-scene in animation. To emphasize the direct connection between the frame's visual peculiarity and the director's opinions, the mise-en-scene of director centered animation created under a restricted environment was reviewed. Mise-en-scene which started from movie critics theory does not simply mean the arrangement of images in a frame. Mise-en-scene emphasizes the exposure of the work's motive by the visual components. The animation's assuming the middle point of environmental share possessed by play and movie when schematizing the genre peculiarity of animation, play and movie was a noteworthy result. It can be said that the cause is that the animation's peculiarity yield different results depending on the making methods; we verified that this is a key factor in the analysis of animation's mise-en-scene. I emphasized that the peculiarity of animation mise-en-scene is in its making method and material and suggested identifying the work's making methods and analyzing the work's aesthetic results derived in this way. The russian animation which was perceived as peripheral arts was relatively free from the burden of censorship while receiving support from the Soviet as a media for propaganda. The russian animation's mise-en-scene which found the material for its works in the country's folklore was metaphorical, focused on new expression forms and achieved experimental elements. Russian animation pursues a unique aesthetic world through space expression based on the forms of opera or ballet and heavy motions formed static inbetweens.

• Journal of the Korean earth science society
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• v.34 no.7
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• pp.693-710
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• 2013

This study investigates the distribution of suspended particulates during the Asian dust period in Busan, Korea in the spring of 2009. Weather map and automatic weather system (AWS) data were used to analyze the synoptic weather conditions during the period. Particulate matter 10, laser particle counter data, satellite images and a backward trajectories model were used to analyze the aerosol particles distribution and their origins. In Case 1 (20 February 2009), when the $PM_{10}$ concentration increased, the aerosol volume distribution of small ($0.3-1.0{\mu}m$) particles decreased, while the concentration of large ($1.0-10.0{\mu}m$) particles increased. When the $PM_{10}$ concentration decreased, the aerosol volume distribution was observed to decrease as well. The prevailing winds changed from weak northerly winds to strong southwesterly winds when the concentration of the large particles increased. The correlation coefficient between the $PM_{10}$ concentration and aerosol volume distribution of large particles showed a high positive value of over 0.9. The results from the trajectory model show that the Asian dust originated in the Gobi desert and the Nei Mongol plateau. In Case 2 (25 April 2009), when the $PM_{10}$ concentration increased, the aerosol volume concentration of small ($0.3-0.5{\mu}m$) particles decreased, but the concentration of large ($0.5-10.0{\mu}m$) particles increased. The opposite was observed when the $PM_{10}$ concentration decreased. The prevailing winds changed from northeasterly winds to southwesterly and northeasterly winds. The correlation coefficient between the $PM_{10}$ concentration and aerosol volume distribution of large particles ($1.0-10.0{\mu}m$) showed a high positive value of about 0.9. The results from the trajectory model show that the Asian dust originated in Manchuria and the eastern coast of China.

• Journal of the Korean Geographical Society
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• v.40 no.2 s.107
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• pp.221-241
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• 2005

Land Use and Land Cover Changes (LUCC) occur over a wide range of space and time scales, and involve complex natural, socio-economic, and institutional processes. Therefore, modelling and predicting LUCC demands an understanding of how various measured properties behave when considered at different scales. Understanding spatial and temporal variability of driving forces and constraints on LUCC is central to understanding the scaling issues. This paper aims to 1) assess the heterogeneity of land cover change processes over the landscape in northern Ghana, where intensification of agricultural activities has been the dominant land cover change process during the past 15 years, 2) characterise dominant land cover change mechanisms for various spatial scales, and 3) identify the optimal spatial scale for LUCC modelling in a savanna landscape. A multivariate statistical method was first applied to identify land cover change intensity (LCCI), using four time-sequenced NDVI images derived from LANDSAT scenes. Three proxy land use change predictors: distance from roads, distance from surface water bodies, and a terrain characterisation index, were regressed against the LCCI using a multi-scale hierarchical adaptive model to identify scale dependency and spatial heterogeneity of LUCC processes. High spatial associations between the LCCI and land use change predictors were mostly limited to moving windows smaller than 10$\times$10km. With increasing window size, LUCC processes within the window tend to be too diverse to establish clear trends, because changes in one part of the window are compensated elsewhere. This results in a reduced correlation between LCCI and land use change predictors at a coarser spatial extent. The spatial coverage of 5-l0km is incidentally equivalent to a village or community area in the study region. In order to reduce spatial variability of land use change processes for regional or national level LUCC modelling, we suggest that the village level is the optimal spatial investigation unit in this savanna landscape.

• Investigative Magnetic Resonance Imaging
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• v.7 no.1
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• pp.47-55
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• 2003

Purpose : Cortical dysplasia is known to be of variety of MR imaging findings. We attempted to classify MR imaging findings of cortical dysplasia into several types and to correlate those with histopathologic grades and subtypes. Materials and Methods : Preoperative MR images of 97 patients with pathologically-proven cortical dysplasia were retrospectively reviewed with knowledge of the diagnosis and operative sites. The patients were divided into MR-positive and MR-negative groups based on the presence or absence of MR imaging abnormalities. In MR-positive group, MR imaging features were arbitrarily classified into four types (atrophic, cortical-band, inward-rounding, and nonspecific types) on the basis of size of the gyrus and adjacent CSF space, cortical thickness, signal intensity of the subcortical white matter, and blurring of the gray-white matter junction. The pathologic findings were also retrospectively reviewed without knowledge of MR imaging findings and divided into three grades (mild, moderate, and severe) and two subtypes (nonballoon-cell and balloon-cell). Pathologic grades and subtypes we re compared between MR-positive and MR-negative groups. Four MR types of the MR-positive group were correlated with the pathologic grades and subtypes. Results : MR-positive and MR-negative groups consisted of 39 (40%) and 58 (60%) patients, respectively. Of the MR-positive group, atrophic type was seen in 13 patients (33 %), cortical-band type in 9 (23%), inward-rounding type in 9 (23%), and nonspecific type in 8 (21%). There was no significant difference in the pathologic grades between MR-positive and MR-negative groups, although MR-positive group tended to have higher pathologic grades than MR-negative group did. Balloon-cell subtype was found significantly higher in MR-positive group than in MR-negative group (p<0 .05): 21% (8/39) versus 5% (3/58). The inward-rounding type corresponded to the pathologically severe grade and balloon-cell subtype in 78% (7/9) and 56% (5/9) of the patients, respectively, while the atrophic type to the mild grade and nonballoon-cell subtype in 77% (10/13) and 100% (13/13), respectively. Conclusion : A variety of MR imaging abnormalities were found in 40% of the patients with cortical dysplasia and those were classified into four types (atrophic, cortical-band, inward-rounding, and nonspecific types), of which the inward-rounding type correlated well with the pathologically severe grade and balloon-cell subtype, whereas the atrophic type with the mild grade and nonballoon-cell subtype.