• Communications of the Korean Mathematical Society
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• v.12 no.3
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• pp.717-723
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• 1997

The compact transformation group has been developed with lots of properties. Many properties which are satisfied on G-space for compact group G do not hold for noncompact case. To recover some theory on spaces with noncompact group action we give some restriction on G-spaces. Hence we introduced Cartan G-spaces and proper G-spaces for our goal and we prove some properties on these G-spaces with noncompact G.

• Bulletin of the Korean Mathematical Society
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• v.40 no.2
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• pp.309-317
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• 2003

In this paper we study the relation of Euler characteristic with respect to cohomology with compact support in F$_{p}$-coefficient for the fibration of ENR's and generalize some properties on proper G-spaces for locally compact Lie group G.G.

• Honam Mathematical Journal
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• v.34 no.4
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• pp.495-504
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• 2012

Let G be a semialgebraic group and M a proper semi-algebraic G-set which is locally complete. In this paper we show that the orbit space M/G has a semialgebraic structure such that the orbit map is semialgebraic.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.78-81
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• 2008

The number of clinics for Oriental Clinic is increasing sharply in Korea after the inception of National Health Insurance System in 1987. However there have been many troubles in making efficient plans for oriental clinic facilities because of the lack of proper guidelines related to the design of them. This research was conducted as part of the planning project for the "G" Oriental Clinic. The purpose of this project Is to place a optimal number of beds in a small oriental clinic and medical-environmental friendly design After arranging necessary spaces, such as the Director's Office, Herbal Medicine Preparation Room, Multipurpose Room, Medicine Cabinet, and Waiting Room in the clinic, partitions are used to differentiate the spaces and the storage area.

• Communications of the Korean Mathematical Society
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• v.24 no.1
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• pp.5-16
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• 2009

In this paper, we obtain the general solution and the generalized Hyers-Ulam-Rassias stability for a following functional equation $$\sum\limits_{i=1}^mf(x_i+\frac{1}{m}\sum\limits_{{i=1\atop j{\neq}i}\.}^mx_j)+f(\frac{1}{m}\sum\limits_{i=1}^mx_i)=2f(\sum\limits_{i=1}^mx_i)$$ for a fixed positive integer m with $m\;{\geq}\;2$. This is applied to investigate derivations and their stability on proper Lie $CQ^*$-algebras. The concept of Hyers-Ulam-Rassias stability originated from the Th. M. Rassias stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72(1978), 297-300.

• The Journal of the Acoustical Society of Korea
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• v.37 no.5
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• pp.363-368
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• 2018

Recently a slat type ceiling is widely used in various spaces, such as music performance spaces and concourse of airport and a general reception area of a building. However, it is hard to find a proper design guideline or material useful in designing such spaces, due to the lack of relevant researches on the effect of a slat ceiling on room acoustics. The present work investigated the effect of a slat type ceiling using a physical scale model method. A 1/20 scale model of a small shoe-box type music performance hall was built and a slat ceiling with different configurations was installed. 6 cases of different ceiling configurations were considered with the combination of 2 slat ceiling height cases and 3 distance cases between slats. The effect of a slat ceiling on the acoustics of a room was evaluated by measuring reverberance($T_{30}$), intelligibility and clarity($D_{50}$ and $C_{80}$), and loudness(G and $G_{80}$).

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.855-861
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• 2009

This paper presents the concept of dynamically reconfigurable space by introducing smart building components. Thanks to the advances in ubiquitous computing and ITC technology, we are able to expect, in the near future, the aspects of future buildings which may transform their appearance and states to perform specific functions. In other words, it is certain that the building space will actively reconfigure itself to accommodate user's needs once we acquire proper technologies. Based on the assumption that building components may not be transformed through the magical process, but change its physical states (e.g. transparency, illumination, display contents, etc.) and functions of embedded devices (e.g. audio, actuators, sensors, etc.), we can envision a dynamically reconfigurable smart space. In order to conceptualize such spaces, critical surveys have been conducted on current works of leading architects. When the room needs to be used as a specific function room, the components need to change theirs states or to behave in a certain manner to create an optimum environment. Our model defines the relationships and elements to describe the mechanism of reconfigurable space. We expect this model provides a conceptual guideline for developing a smart building components based on spatial service scenarios. Therefore, a future smart spaces implemented by integrating various technologies are not designed in deterministic manner, so that spatial functions are expanded without constrained by physical existence.

• The Journal of the Acoustical Society of Korea
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• v.21 no.8
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• pp.708-718
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• 2002

In this paper, the problems in identifying the noise sources by using the sound intensity technique are dealt with for the general radiated near-field from vibro-acoustic sources. For this purpose, a three-dimensional model structure resembling the engine room of a car or heavy equipment is considered. Similar to the practical situations, the model contains many mutually coherent and incoherent noise sources distributed on the complicated surfaces. The sources are located on the narrow, connected, reflecting planes constructed with rigid boxes, of which a small clearance exists between the whole box structure and the reflecting bottom. The acoustic boundary element method is employed to calculate the acoustic intensity at the near-field surfaces and interior spaces. The effects of relative source phases, frequencies, and locations are investigated, from which the results are illustrated by the contour map, vector plot, and energy streamlines. It is clearly observed that the application of sound intensity technique to the reactive or reverberant field, e.g., scanning over the upper engine room as is usually practiced, can yield the detection of fake sources. For the precise result for such a field, the field reactivity should be checked a priori and the proper effort should be directed to reduce or improve the reactivity of sound field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.28-44
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• 1998

This study was conducted to suggest the ecological restoration strategies for the disturbed landscapes by theoretical study. Especially, it is aimed to suggest three objectives for restoration by using native plants ; (1) prevention or reduction of wind and water erosion, (2) provision of food and cover for variety of animal species, (3) improvement of the visual or aesthetic quality of disturbed sites. The main results were summarized as follows. 1. Cooperation between restoration ecologists and restoration practitioners is needed to delineate a scientific approach to restoration ; (1) Being aware of published literature that describes similar work and/or establish general principles. (2) Preparedness to carry out proper experiments to test ideas. (3) Preparedness to monitor fundamental parameters in a restoration scheme. (4) Providing information about the behavior of species. (5) Publish results. 2. There are three models of succession in theories of plant succession. The tolerance and facilitation models were recommended to ecological restoration. The inhibition model applies in most secondary succession, but the actual species which are introduced first may inhibit the germination and growth of slower-growing species, or they may prevent the growth of other species whose propagules arrive later. 3. The objectives of erosion control, wildlife habitat provision, and visual quality improvement are not mutually exclusive. However, many revegetation practices in the past have emphasized one of these aspects at the expense of the others. 4. A native plant community can be the model of ecological restoration. By stylization/abstraction of native plant community, trying to learn the most essential characteristics of community types - environmental factors ; dominant, prevalent, and "visual essence" species composition - in order to use such information in restoration. 5. After developing mass/spaces plan, match plant communities to the mass/space plan. In utilizing community grouping, there needs aesthetic ability to understand design elements. 6. Several hydrophytes such as Pennisetum saccharifluous, Themeda triandra, Cirsium pendulum show relatively good germination rates. In case of mesophytes and xerophytes, Arundinella hina, Artemisia princeps, Oenothera odorata and legumes seem to have quick-germinating abilities at barren sites. Pinus thunbergii, Rhus chinensis, Evodia daniellii, Alnus firma and Albizzia julibrissin can be considered as "late succession" woody plants because they show low germinating rates and slow growing habitat. 7. The seeds used for restoration should be collected within a certain radius of where it will be planted. Consideration in genetic issues in the collection and use of germplasm can increase the odds for successful restoration efforts. 8. The useful model in the "drift" pattern occurs so abundantly in naturally evolving landscapes. As one species diminishes in density, a second or third species are increased. Thus, dynamic interactions between species are created. Careful using of "drift phenomenon" in planting was recommended. 9. Virtually no stand of vegetation today is immune from the introduction and/or spreading of exotic species. Therefore, the perpetuation of a restored sites requires conscious monitoring and management. Thus, management would be the most important process in ecological restoration. 10. In order to keep the sites "natural", alternative management strategies would be applied in management ; Atenative management strategies are decelerating successional process, accelerating successional processes or modifying species composition. As management tools, mechanical, chemical, biological or environmental factor manipulation, e.g., fire could be used.