• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.67.1-67.1
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• 2019

We present 2-dimensional continuum radiative transfer modeling for EC53. EC 53 is a Class I YSO, which was brightened at $850{\mu}m$ by a factor of 1.5. This luminosity variation was revealed by the JCMT Transient Survey. The increase in brightness is likely related to the enhanced accretion. We aim to investigate how much increase of protostellar luminosity causes the observed brightness increase at $850{\mu}m$. Thus we modeled the SED of EC 53 both in the quiescence and (small scale) outburst phases, with and without the external heating from the interstellar radiation field (ISRF). We found that the internal protostellar luminosity should increase more to fit the observed flux enhancement if the ISRF is considered in the model.

• Advances in aircraft and spacecraft science
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• v.10 no.5
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• pp.439-455
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• 2023

Free surface fluid oscillation in prolate spheroidal tanks has been investigated analytically in this study. This paper aims is to investigate the sloshing frequencies in spheroidal prolate tanks and compare them with conventional cylindrical and spherical containers to select the best tank geometry for use in space launch vehicles in which the volume of fuel is very high. Based on this, the analytical method (Fourier series expansion) and potential fluid theory in the spheroidal coordinate system are used to extract and analyze the governing differential equations of motion. Then, according to different aspect ratios and other parameters such as filling levels, the fluid sloshing frequencies in the spheroidal prolate tank are determined and evaluated based on various parameters. The natural frequencies obtained for a particular tank are compared with other literature and show a good agreement with these results. In addition, spheroidal prolate tank frequencies have been compared with sloshing frequencies in cylindrical and spherical containers in different modes. Results show that when the prolate spheroidal tank is nearly full and in the worst case when the tank is half full and the free fluid surface is the highest, the prolate spheroidal natural frequencies are higher than of spherical and cylindrical tanks. Therefore, the use of spheroidal tanks in heavy space launch vehicles, in addition to the optimal use of placement space, significantly reduces the destructive effects of sloshing.

• Korean Institute of Interior Design Journal
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• v.15 no.1 s.54
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• pp.131-138
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• 2006

This paper compares presentation methods which are characteristic among museums of natural history in Korea. The different medium for exhibitions are divided into Specimen, Model or Panel Type Displays, Video Presentations, Sound, and Tactile Exhibits, and further classified as Fixed (A Type), Observable (B Type), or Performance Art (C Type) Displays. The museums we studied were the Seodaemun Museum of Natural History, Ewha Womans University Museum of Natural History, Seoul National Science Museum, Gyeryongsan Natural History Museum, the National Science Museum, Mokpo Natural History Museum, and the JejuDo Folklore and Natural History Museum. A study of these museums' approaches to display composition, and exhibition methods according to their exhibit types and contents, revealed the following results: The museums of natural history rely more on Fixed type displays to show information, with appropriate uses of the Observable and the Performance Art type exhibitions. Better utilization of appropriate medium is desired for display contents of Astronomy Space Earth, Minerals Rocks Geology, Animals, Plants, Insects, Prehistoric Organisms Environment, and Anthropology.

• The Korean Journal of Air & Space Law and Policy
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• v.21 no.1
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• pp.215-236
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• 2006

This article focused on the meaning of the 1979 Moon Treaty and its future. Although the Moon Treaty is one of the major 5 space related treaties, it was accepted by only 11 member states which are non-space powers, thus having the least enfluences on the field of space law. And this article analysed the relationship between the 1979 Moon Treay and 1967 Space Treaty which was the first principle treaty, and searched the meaning of the "Common Heritage of Mankind(hereinafter CHM)" stipulated in the Moon treaty in terms of international law. This article also dealt with the present and future problems arising from the Moon Treaty. As far as the 1967 Space Treaty is concerned the main standpoint is that outer space including the moon and the other celestial bodies is res extra commercium, areas not subject to national appropriation like high seas. It proclaims the principle non-appropriation concerning the celestial bodies in outer space. But the concept of CHM stipulated in the Moon Treaty created an entirely new category of territory in international law. This concept basically conveys the idea that the management, exploitation and distribution of natural resources of the area in question are matters to be decided by the international community and are not to be left to the initiative and discretion of individual states or their nationals. Similar provision is found in the 1982 Law of the Sea Convention that operates the International Sea-bed Authority created by the concept of CHM. According to the Moon Treaty international regime will be established as the exploitation of the natural resources of the celestial bodies other than the Earth is about to become feasible. Before the establishment of an international regime we could imagine moratorium upon the expoitation of the natural resources on the celestial bodies. But the drafting history of the Moon Treaty indicates that no moratorium on the exploitation of natural resources was intended prior to the setting up of the international regime. So each State Party could exploit the natural resources bearing in mind that those resouces are CHM. In this respect it would be better for Korea, now not a party to the Moon Treaty, to be a member state in the near future. According to the Moon Treaty the efforts of those countries which have contributed either directly or indirectly the exploitation of the moon shall be given special consideration. The Moon Treaty, which although is criticised by some space law experts represents a solid basis upon which further space exploration can continue, shows the expression of the common collective wisdom of all member States of the United Nations and responds the needs and possibilities of those that have already their technologies into outer space.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.3
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• pp.66-73
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• 2004

As a rocket propellent of hydrocarbon fuels, the characteristics of liquefied natural gas was evaluated with the viewpoint of the constituents and content, the cooling performance as a coolant, and characteristic velocity and specific impulse as parameters of the engine performance. Content of methane was a principal factor to determine the characteristics as a rocket propellant and more than 90% of it was needed as a fuel and coolant in the regenerative cooled liquid rocket engine. Some constituents of the liquefied natural gas can be frozen by the pre-cooling of the pipe lines, therefore they can be a factor disturbing the normal working of engine. In case the content of methane is around 90% in the liquefied natural gas, a normalized stoichiometric O/F mixture ratio of 0.75 is suggested for a nominal operation condition to get the maximum specific impulse and characteristic velocity.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.87-101
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• 2010

This research has a significance on providing basic material of landscape ecological planning and open space planning of the future site by selecting Sinseo innovative city area, large residential land development district in rural area, by classifying biotope types and implementing recreational value assessment in the level of area. First of all, as a result of classification of biotope types in research site, total 11 biotope type groups including stream biotope and its subordinate 51 biotope types. Also, as a result of the first value assessment of classified biotopes, there are total 5 types such as vegetation-full natural river, fallow ground in I grade. In addition, it is analyzed that grade II have 18 types, III are 10, IV are 12, the least valuable V are 6. Especially, grassland biotope(GD) was classified into grade II, which is one grade raised, because it is analyzed that it has high value in terms of normal access and availability although it was assessed as grade ill in terms of natural experience quality. Lastly, as a result of the second assessment, special areas for natural experience and recreation(1a, 1b) are 15, areas for natural experience and recreation(2a, 2b, 2c) are 47. Especially, the 52th drawing mark space was grade II in the first assessment but its value grade was upgraded because of its high value in terms of use evidence, size of the area, accessibility with housing area, history and cultural character and so on.

• Journal of the Korea Furniture Society
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• v.20 no.5
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• pp.504-516
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• 2009

Korean traditional architecture has been carried out in the manner that it harmonized surrounding natural environments and never disturbed them in the scale which did not overwhelm the nature, based on the view of architecture predicated on Yin Yang School. The exposed grain of the wood like pillar, hinge and house rafte, the linear expression of the construction material and the formation between the window and door monopolizing the front side presented a harmony with the nature showing the linear structure. Furthermore the ceiling is low due to the sit life style thanks to the ondol (Korean under-floor heating system and the furniture was made in simple manner to utilize the space as large as possible, for the interior was narrow and close, and also the furniture placing in the middle of the room was movably manufactured to improve the room space. Like this Korean traditional furniture was close associated with the low height and simplicity and harmonized with the blank of the wall accordingly, and it characterized linear & planar natural beauty focusing on the simple and refined unique beauty, because it was made in a good harmony with the interior utensils. This study has presented that the organic characteristics of Korean traditional aesthetic of architecture and the natural beauty being intrinsic in traditional furniture have a mutual relation on the basis of not only the visual recognition, also the aesthetic of naturalism made of the natural material, the constructional naivety as a frame method and the linear & planar formative beauty shown in appearance.

• Korean Institute of Interior Design Journal
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• v.25 no.2
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• pp.70-82
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• 2016

The playgrounds installed in the city try a variety of changes in play equipment more than traditional playgrounds, these playgrounds with formal rides are still different from nature friendly playground. For this reason, when in 2014 the department of environment pushed forward 'Aitteulag' project constructing ecological playground, the department aimed to provide the natural ecological spaces that are insufficient in the city and act as play space for children, leisure and community space for residents. Therefore, after inspecting 10 ecological playgrounds in Europe and Japan, in this study we suggested the construction guidelines of ideal ecological playground by comparing and analyzing these cases. We checked the environment-friendliness of these playgrounds in the 2 fields (playground component, ecological program) based on the ecological playground guidelines presented by the ministry of environment. The playground components are classified as siting location, spatial configurations, natural elements, play area, amusement facilities, play materials, open spaces, additional facilities. The ecological programs are divided into habitat, species, natural material, five senses. The following is the summary of the results about the reflection of eco-friendly planning factors. In terms of "habitat": bush and shade wood were highest at 95%. In terms of "species": local indigene(100%) and habitat for insects(95%) were higher than others. In terms of "natural material": wood(61.1%) was the highest. In terms of "details of wood(61.1%)": wood fence (95%), exploring wood and using sticks(85%) were higher than others. In terms of "five senses": hearing (32.1%), tactile(26.4%), and visual(23.9%) were in order. Therefore, on the basis of these results, this study proposed the planning factors that should be considered and complemented more in the construction of domestic urban ecological playground in future.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.4
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• pp.1-17
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• 2012

This study was carried out to propose the improved method by analyzing the change of green space arrangement and planting structure of apartment complexes in Seoul. 12 survey sites, which have obvious differences, were selected by reflecting the change of floor area ratio, underground parking place, and green space ratio. We divided the survey sites into four types that high green ratio(over 40%) apartment on natural ground, low green ratio(under 40%) apartment on natural ground, low green ratio(under 40%) apartment on artificial ground, and high green ratio(over 40%) apartment on artificial ground each period based on green space ratio and ground structure, plant crown volume, planting density, and planting pattern. The main factors of change of green space arrangement were green space ratio and ground structure. The Green space ratio was changed by the floor area ratio with constructing underground parking place and floor area ratio was adjusted by government policy and economic status. Average width of front green area has been changed from 10.0m in high green ratio apartment on natural ground for 3.5m, 2.7m, and 4.5m each period. The average width of the buffer green area has been changed from 15.0m in high green ratio apartment on natural ground of 7.7m, and 2.7m by extending parking place in the low green ratio apartment of artificial ground, so buffer green areas have been reduced and disconnected. So buffer green area in apartment complexes has been extended that the average width of the buffer green area was 3.8m caused by growing recognition of green since 2001. The ratio of native plant in canopy layer was increased from 45.1 % in the case of the high green ratio apartment of natural ground in 1980~1983 to 55.6%. Average plant crown volume increased from $1.27m^3/m^2$ in high green ratio apartment on natural ground for $3.47m^3/m^2$ in a low green ratio apartment on natural ground. But average plant crown volume is $0.27m^3/m^2$ in the high green ratio apartment of the artificial ground plant density of canopy layer was changed from 5 individuals per $100m^2$ to 14.5 individuals per $100m^2$. We should construct the buffer green area with natural ground and get the function of ecological and beautiful environment regarding to garden concept in case of front green area, width 4.5m. We should get the function of increasing green volume by multi-layer planting with shade woody species and flower woody species in case of back-side green area, width over 5.0m. We should get the function of covering the wall and increasing green landscape by planting with high woody species in case of side green area. We should apply the ecological planting technique to buffer green area and connect buffer green area to inner green area in apartment complexes.

• Journal of the Korean housing association
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• v.16 no.6
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• pp.101-109
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• 2005

As a circumstantial-existance character (the human character who takes action after grasping circumstances and fears things with reason) the Japanese were more interested in the active doctrines of Wang Yang-ming than other speculative studies. All of people were inhumanely incorporated into the rigorous class system under pressure in the samurai society. In the atmosphere of the society a natural phenomenon was understood as the ksana of change, and instead of the whole, the part was mainly described with emphasis on the reality. Therefore nature came near to the man after being reduced and then was symbolized in the Interior space. Also the classification of spaces, that is to say, the settlement of borders by the social position was shown in the great interior space like a labyrinth. As a self-existance character(the human style who carves out for and does not have a regard other's feeling), however, the Korean were much influenced by the Taoist Idea as they tried to be similar to nature in nature itself. Therefore the idea of Asaniskrota was in their origin. There was a tendency for space to be extended toward the outdoor in Korea, since the Korean people who are speculative and like to be natural tried to be close to nature. Therefore the division of spaces according to class and sexuality and the settlement of borders were already shown in outside by Che-Na-Num(Divided-Mass:Koren's own style). These are closely related with that houses were built after a village settle down in Korea while built before a village settle down in Japan. Architectural space consists of the interior and the exterior. The layout and (on of architectural space has a great variety of characters by region and culture. In other words, it can be understood which has a priority between the interior and the exterior in developing the layout and the form of architectural space. Belonging to the culture area of Chinese characters with Korea, Japan has maintained its own Identity. It has an identity in the layout and form of architectural space as well. Therefore, the architecture and architectural theories of the two countries were compared and analyzed with priority given to the traditional architecture, also the backgrounds of architecture and architectural theories of two countries were examined in this study. This study shows that each country has different characters in how to introduce nature, how to expand space and how to compose windows, including the view of nature and the cult of space. As a result, the space in Korean architecture has relatively the exterior-oriented character but in Japan architecture spatial character is interior-oriented. The interior-oriented character can be relevant to the word 'reduction' and the exterior-oriented character to 'extension' after all. Also it can be thought that each character has a great relation with climate and idea of people in power.