• 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 Environmental Policy
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• v.9 no.2
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• pp.157-184
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• 2010

Global climate change is destroying the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. The Intergovernmental Panel on Climate Change (IPCC 2007) makes "changes in rainfall pattern due to climate system changes and consequent shortage of available water resource" a high priority as the weakest part among the effects of human environment caused by future climate changes. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes, and "direct" interactions, being indirectly affected through recharge. Therefore, in order to quantify the effects of climate change on groundwater resources, it is necessary to not only predict the main variables of climate change but to also accurately predict the underground rainfall recharge quantity. In this paper, the authors selected a relevant climate change scenario, In this context, the authors selected A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by period and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model for groundwater recharge, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems associated with how the groundwater resource circulation system should be reflected in future policies pertaining to groundwater resources, it may be urgent to recalculate the groundwater recharge quantity and consequent quantity for using via prediction of climate change in Korea in the future and then reflection of the results. The space-time calculation of changes to the groundwater recharge quantity in the study area may serve as a foundation to present additional measures for the improved management of domestic groundwater resources.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.20-33
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• 2020

This study aims to examine the trends in the preservation of urban public parks with a focus on the international movement to acknowledge and preserve the heritage value of urban parks. First, the background in which the concept of "historic urban park" first appeared internationally, as well as the current situation were investigated. Then, the cases of the United Kingdom (UK), the United States (US), and Japan, all of which are already preserving and managing urban public parks, were analyzed. In the ICOMOS-IFLA Document on Historic Urban Public Parks, the International Council on Monuments and Sites (ICOMOS), which is a group of specialists dedicated to the conservation and management of cultural heritage, mentions that it is necessary to maintain the social, intangible, aesthetic, ecological, and civic values of historic urban public parks. In addition, according to ICOMOS, it is necessary to preserve elements of parks, such as space composition, topography, light, and environment. The UK, the USA, and Japan have their own unique characteristics for the background of preserving urban parks, the preservation system, the selection of parks to be preserved, and the elements to be preserved within the park. The UK has categorized parks into certain types from each period and has tried to preserve the common elements in each type. The US has selected the parks to preserve by determining the meaning of the parks itself considering multiple aspects, embracing not only the physical form of the parks, but also the culture, monumentality, and social values. Recently, Japan began the preservation of historic urban parks as a matter of policy and started to implement a preservation policy by investigating modern parks that are believed to be worth preserving. Specialists in cultural heritage preservation have argued that the method of preservation of historic urban parks must differ from that of other parks or gardens. Nonetheless, observing cases in these three countries showed that, regardless of their administrative and legal systems regarding cultural heritage and urban public parks, their policies were still limited to preserving only the physical elements of parks. The direction and methodology for the preservation of historic urban parks must be developed further and elaborated upon in terms of the evolving concept and definition of heritage. Urban parks are where various historic values are accumulated, connoting historical meanings dealing with the memories of the parks and the urban dwellers. This study found that, worldwide, park management has been carried out in a way that the historic values of parks are respected and preserved. This global trend in preserving the historic values of urban public parks has significant implications for the management of urban public parks in Korea that are being formed and renewed repeatedly.

• 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.

• The Journal of Art Theory & Practice
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• no.2
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• pp.75-120
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• 2004

Studies on western art in Korea has been caught in a dilemma that they could deal with only those things which had been arranged according to their 'historical generalization' in their contexts because of the bounds of time and space. It is not trivial that such conditions affect art studies in Korea. Access to the original texts and to their contexts of production is so restricted that the studies on them are prone to he superficial. And it is not independent on the politics of Korean art scene. Such factors are on the background of Korean art's excessive 'assimilation or accordance' with western art. The domestic studies on western art history and art theory have failed to notice the differences in context and Korean art has simply mediated or reproduced the restricted information by those studies. Also the studies on western art in Korea have been made use of as a justifying method of one's own academic domains. In such situations we should lead the studies on western art history and western art theory to a more reflective direction and confirm that the studies should not have any privileges of the realities. And we should try to reform a scholarship which participates in our life and existence. The field of domestic studies on western art history and western art theory should free itself from the invention of objectivity or the neutrality of mechanical reading and turn its eyes to the realities of life where events happens. Constantly suggesting which way Korean art and world art should go has to be the field's new coordinates.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.258-292
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• 1996

In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.368-372
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• 1999

Background: Although there have been few reports about minimal skin incision for the repair of congenital heart lesions, minimizing an unsightly scar is a particularly important factor in growing children. We have adopted a technique that permits standard full sternotomy, conventional open chest cardiopulmonary bypass, aortic cross-clamping, left atrial vent, and antegrade cardioplegia with minimal surgical scar. Material and Method: With minimal skin incision and full sternotomy, 40 patients with congenital heart disease underwent open heart surgery from April 1997 through September 1997. Defects repaired included 30 ventricular septal defects, 4 atrial septal defects, and 1 sinus Valsalva aneurysm in 35 children(M:F=17: 18), and 3 Atrial septal defects, 1 ventricular septal defect, and 1 partial atrioventricular septal defect in 5 adults(M:F=1:4). Midline skin incision was performed from the second intercostal space to 1 or 2 cm above the xiphoid process. For full sternotomy, we used the ordinary sternal saw in sternal body, and a special saw in manubrium under the skin flap. During sternal retraction, surgical field was obtained by using two retractors in a crossed direction. Result: The proportion of the skin incision length to the sternal length was 63.1${\pm}$3.9%(5.2∼11cm, mean 7.3cm) in children, and 55.0${\pm}$3.5%(10∼13.5cm, mean 12cm) in adults. In every case, the aortic and venous cannulations could be done through the sternal incision without additional femoral cannulation. There was no hospital death, wound infection, skin necrosis, hematoma formation, or bleeding complication. Conclusion: We conclude that minimal skin incision with full sternotomy can be a safe and effective alternative method for the repair of congenital heart diseases in children and adults.

• The Journal of Art Theory & Practice
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• no.7
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• pp.37-64
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• 2009

The theories of Korean Public Art originated by the artists who were against dictatorship and they associated with democratic politicians. They criticized the Fine art that were supported by the dictatorship and gave their efforts for restoration of 'resistance paintings(against dictatorship)', 'proletarian painting', 'realism painting'. In addition, they participated new social ideology(democracy) movement and demonstrated for their rights in arts. These became the main kernel the public art theory was initiated. The public artists splitted into several different parts and participated in the democratic social movement as well as the art movement for freedom. They opened various art exhibitions within different genre, diverse space for various art section such as an exhibition hall, a factories, a university, or a congregation square. Furthermore, the public art theorists published their divergent views through newspaper/broadcasting or unauthorized printed materials. Most of the public artist and the theorists kept their relationship strongly until 1985, the time when 'National Arts Association' started. In 1983 and 1984, they were clearly separated into two parts; artists(move only in art museums) and activists(move in public spaces like school, convention square etc). Their ideological separation also took out national problems. The division; professional artists and armatures, became the social issue as a social stratification matter. And in creating method, there are also other conflicts; critical realism, and public realism as well as western painting and traditional one. These kinds of separation and conflicts made different Public artists associations, under divergent names; 'Reality and Speak'(R&S), 'KwangJu Art Association', 'Durung', 'Dang(Land)', and 'Local Youth Students Association'. In addition, their ideology and pursuit toward art movements were very difference. However, the differences and conflicts weakened When the oppression of democratic education from new dictatorship(Pres. Jun, Doo Hwan) came out. In August. 1985 the government opened to the public so called, 'The draft of School stabilization law'(Hankwon Anjung Bup) to control the teachers' rights and that initiated bigger street demonstration and conflicts between police and educators. In November.1985, assembly meeting of National Arts Association in democracy opened as 'ONE' combined organization. In this presentation, I'd like to summarize the stream of art movement until 1984, and clarify the main art theories that lead the Public Art Movements in 1980s. The main theories in 1980s are crucial because they become the origin of public art theories. This presentation started with O,youn's "Hyunsil Dong In the first declaration" and explained the absent of practice in 1970s. In addition, Won, Dong Suk 's theory was mentioned as all over struggles in theories before 1980s. GA and R&S 's founding declarations in 1970s were the start of public art theorists' activities and this article reported the activities after the declarations. First, realism base on the consciousness of reality. Second, practice art democratization based on the ideology. Third, the subject of public art movement based on understanding people's social stratification structure. Fourth, the matters of national forms and creative ways in arts based on showing reality. Fifth, the strong points in arts that the practitioners accepted. About the public art theories around 1984, I discussed the dividing point of public art theories that were shown in 'generation theory', 'organization theory', and 'popularization theory' by the practitioners. The public realism theory that subjects the contradiction of reality and point out the limits of critical realism not only showing the new creative ways but also giving the feeling of solidarity to the public art activist groups. After that, public art movements expressed 'Dismentlement of Capitalism' and 'Public revolution'. In addition, the direction of public art movements were established strongly. There were various opinions and views during the start and formation of the public art theories. The foundation of theorists activities derived from the practitioners who had the concept based on stratification and nationalism. The strong trend of group division spreaded out by practitioners who opened art work together in factories, universities, squares and rural areas. Now many lively active practitioners are gone to the other field not related with arts, and others join into professional art field not public art one with unknown reason. The theorists have the same situation with the practitioners. It means to me that theory always have to be based on the practice.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.43-54
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• 2009

This study attempted to develop a model for selecting sites for ecologically effective, multi-functional wetlands during the environmental and ecological planning stage, prior to land use Planning. This model was developed with an emphasis upon the creation of a water circulation system for a newly-created city, dispersing and retaining the run-off that is increased due to urbanization and securing spaces to create wetlands that can promote urban biodiversity. A series of Precesses for selecting sites for wetland restoration and creation - watershed analysis, selection of evaluation items, calculation of weights, reparation of thematic maps and synthesis - were incorporated into the model. Its potentials and limitations were examined by applying it to the recently-planned WiRae New Community Development Area, which is located in the Seoul metropolitan region. At the watershed analysis stage, the site was divided into 13 sub-catchment areas. Inflow to watersheds including the area was $3,020,765m^3$ Run-off before and after development is estimated as $1,901,969m^3$ and $1,970,735{\sim}2,039,502m^3$, respectively. The total storage capacity required in the development area amounts to $68,766{\sim}137,533m^3$. When thematic maps were overlapped during the selection stage for wetland sites, 13 sub-catchment areas were prioritized for wetland restoration and creation. The locations and areas for retaining run-off showed that various types of wetlands, including retaining wetlands (area wetlands), riverine wetlands (linear wetlands) and pond wetlands (point wetlands), can be created and that they can be systematically connected. By providing a basic framework for the water circulation system plan of an entire city, it may be used effectively in the space planning stage, such as planning an urban eco-network through integration with greet areas. In order to estimate reasonable run-off and create an adequate water circulation system however, a feedback process following land use planning is required. This study strived to promote urban changes in a positive direction while minimizing urban changes in negative forms.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.5
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• pp.41-54
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• 2018

In recent years, as interest in youth startup has increased, the Korean government has established various policies to support young entrepreneurs and actively implements such policies. Especially, as a way to promote youth startup, the development of startup clubs in universities is being suggested, and the importance of startup clubs is growing day by day. As reflected in these points, the Korean government is increasing its budget every year to support the startup clubs of universities, and actively supports the funds and space required for the startup clubs of universities. Unfortunately, however, despite the growing importance of startup clubs and the active support of the government for the startup clubs, academic attempts to see how effectively the startup clubs are operating are not enough. For this reason, this study analyzes the effect of entrepreneurship of university start-up club members on the effectiveness of start-up club. More specifically, in this study, entrepreneurship of club members is classified as risk-taking propensity, proactiveness, and innovativeness, as emphasized in previous researches. We empirically analyzed the effects of these independent variables on the effectiveness of the start-up clubs, focusing on the moderating effect of club members' diversity. We conducted empirical analyses on 1112 start-up club members from 12 universities located in Jeollanam-do and Jeollabuk-do, and the analysis results are as follows. First, the entrepreneurship of the start-up club members, namely risk taking propensity, proactiveness and innovativeness, all have a positive effect on the effectiveness of the start-up club. These results are consistent with the emphasis of many previous studies. The higher the tendency to take risks, the more inclined to move forward through difficulties, and the higher the tendency to break out of the existing framework and pursue new things, suggesting that the effectiveness of the club is enhanced. Second, as a result of verifying the moderating effect of the club members' diversity, it was found that club members' diversity moderates the relationship between the proactiveness of club members and club effectiveness in the negative (-) direction. In other words, the positive effect of the entrepreneurship of club members on the effectiveness of the start-up club means that the proactiveness is weakened in the case of a club having members from different major backgrounds. The results of this study are expected to provide meaningful theoretical and practical implications by identifying the influencing factors of the start-up club's effectiveness, which has not received much attention so far.