• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.6
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• pp.350-360
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• 1988

As the capacity of DC motor is increased, we should recheck several encountered problems like volume increase. Particularly, when a large DC motor should be installed within the limited space, it is necessary to minimize the volume of motor for the effective utilization of the limited space. This paper describes the procedure and the method of finding optimum design of a large DC motor. The result of the optimization will decide the basic dimensions of a large DC motor. The flexible tolerance method and polyhedron searching method are used in this optimization. This result of simulation of the existing large DC motors is compared with the data of the existing large DC motors to confirm the validity of this optimum design.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1061-1064
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• 2009

Through dark injection space-charge-limited current (DI-SCLC) and trap-free SCLC measurements, it has been demonstrated that an indium tin oxide (ITO)/buckminsterfullerene ($C_{60}$) electrode can form a quasi-Ohmic contact with N, N'-bis (naphthalen-1-yl)-N, N'-bis(phenyl) benzidine (NPB). The DI-SCLC results show a clear peak current along with a shift of the peak position as the field intensity varies, implying an Ohmic (or quasi-Ohmic) contact. A theoretical simulation of the SCLC also shows that ITO/$C_{60}$ forms an Ohmic contact with NPB. The Ohmic contact makes it possible to estimate the NPB hole mobility through the use of both DI-SCLC and trap-free SCLC analysis. This also contributes to a reduction in power consumption.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.125-129
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• 2005

As metropolitan areas are rapidly growing in both population and physical size, so too has the problem of traffic congestion. Magnifying this is the limited financial resources and lack of road corridor space available to juggle the many competing demands. High Occupancy Vehicle (HOV) facilities have been implemented in an attempt to alleviate the problem of growing congestion while considering the issue of limited funding and lack of physical space. HOV lanes may increase the efficiency of a road corridor by maximising its person carrying capacity. These facilities are meant to provide priority treatment to HOVs, thereby luring people to choose a transport mode with a higher occupancy than the single occupant vehicle (SOV), such as buses or carpools. This paper analyze the issues surrounding HOV lanes, their effect, problems and their evaluation by using Intergration, that is Traffic Simulation Software, when HOV lanes be implemented in the Olympic Highway.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.533-534
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• 2005

Temperature-dependent current-voltage characteristics of organic light-emitting diodes(OLEDs) were studied in a device structure of ITO/TPD/$Alq_3$/Al. The OLEDs were based on the molecular compounds, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-l,1'-diphenyl-4,4'-diamine(TPD) as a hole transport and tris(8-hydroxyquinoline) aluminum($Alq_3$) as an electron transport and emissive material. The current-voltage characteristics were measured in the temperature range of 10K and 300K. We analyzed an electrical conduction mechanism of the OLEDs using space-charge-limited current(SCLC) and Fowler-Nordheim tunneling.

• Steel and Composite Structures
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• v.30 no.4
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• pp.315-325
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• 2019

Double skin composite walls offer structural and economic merits over conventional reinforced concrete counterparts in terms of higher capacity, greater stiffness, and better ductility. This paper investigated the axial behavior of double skin composite walls with steel truss connectors. Full-scaled tests were conducted on three specimens with different height-to-thickness ratios. Test results were evaluated in terms of failure mode, load-axial displacement response, buckling loading, axial stiffness, ductility, strength index, load-lateral deflection, and strain distribution. The test data were compared with AISC 360 and Eurocode 4 and it was found that both codes provided conservative predictions on the safe side.

• ETRI Journal
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• v.44 no.6
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• pp.925-935
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• 2022

In this study, we propose a limited feedback-based frequency divided group beamforming with sparse space-frequency transmit diversity coded orthogonal frequency division multiplexing (OFDM) system for ultrareliable low latency communication (URLLC) scenario. The proposed scheme has several advantages over the traditional hybrid beamforming approach, including not requiring downlink channel state information for baseband precoding, supporting distributed multipoint transmission structures for diversity, and reducing beam sweeping latency with little uplink overhead. These are all positive aspects of physical layer characteristics intended for URLLC. It is suggested in the system to manage the multipoint transmission structure realized by distributed panels using a power allocation method based on cooperative game theory. Link-level simulations demonstrate that the proposed scheme offers reliability by achieving both higher diversity order and array gain in a nonline-of-sight channel of selectivity and limited spatial scattering.

• Korean Institute of Interior Design Journal
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• v.22 no.6
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• pp.181-189
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• 2013

Space in the past had characteristics of place which are required for specific behavior to be done as we recognized it easily. However, for space in modern times, the purpose, forms and behavior space has, have changed as tools comprising the space have changed. 'Virtual space' which has been a conversation topic recently is unspecific and changeable space whose forms and geological location are not defined clearly. In addition, behaviors caused by this virtual space in combination with real space are taking place. The nature of Flash Mob which is one of the typical behaviors which take place starting from virtual space to be connected with real space, is that it is intangible game culture whose forms and behaviors are not fixed, and it is not limited to a specific place. Besides, Flash Mob is characteristic of representing game culture in modern society, and its nature can be summarized as temporariness, non-placeness, anonymity, double-sidedness and so forth. Since events generally take place in every place when man is involved in space, it's possible to generally think events derived from interpersonal relationships between man and man. We are to study spatial characteristics of Flash Mob by analyzing features and cases of the Flash Mob by means of them.

• Korean Institute of Interior Design Journal
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• v.24 no.2
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• pp.142-150
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• 2015

The purpose of this study is to analysis the change of rural house type and house plans in Bonghwa province. According to definition of rural area, the scopes of the research of rural houses limited the Bonghwa rural area(1 eup, 9 myeon). The method of study is to compare and analyze about housing situation, structure of house, housing type and construction of house space etc. through the statistical data of Bongwha statistical yearbook, space syntax(convex analysis) and other various data etc. during these 10 years. As a results of the analysis 1) According to Change of family member the supply ratio of detached house is steadily decreasing and changing from a detached house to multi-household house in Bongwha areas. 2) Most of houses structure were using lightweight steel construction because of cost-cutting of construction and easy way to construct etc.. 3) The highest Integration space is living space in rural house plans 4) The highest segregation space is bathroom space of master bed room in rural house plans. Some of bed rooms are classed as segregation space regardless of Integration space 5) Traditional front yard's function is changing from the place with the various functions to the place with the specific functions.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.2
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• pp.15-23
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• 2011

The purpose of this study is to analyze the methods applied to educational facilities of Steven Holl's architecture, especially focusing on sensible elements in the public space. Steven Holl has realized distinct space by applying very specific and limited concept. such as perspective space, color, light and shadow, time duration and perception, haptic realm, and proportion & scale. Education facilities designed by Steven Holl, are influenced the sensible aspects of space, form, materials, patterns, and other various sensible elements. Beyond the limits of color and sculptural vocabulary, Steven Holl utilizes a variety of ways which shown in educational facilities design and is identified by the emotional phenomenology of perceptual experience. Various elements in the public space are reinforced through light and materials to make experiential space in the educational facilities. This study used a composition of space that combines various sensible elements, meanings, and senses to examine how Steven Holl's architecture can mediate and reproduce user' emotional experiences and discover the existential relationship between space and user in public space of educational facilities.

• East Asian mathematical journal
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• v.26 no.4
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• pp.553-579
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• 2010

Geometric education emphasize reasoning ability and spatial sense through development of logical thinking and intuitions in space. Researches about space understanding go along with investigations of space perception ability which is composed of space relationship, space visualization, space direction etc. Especially space visualization is one of the factors which try conclusion with geometric problem solving. But studies about space visualization are limited to middle school geometric education, studies in elementary level haven't been done until now. Namely, discussions about elementary students' space visualization process and ability in plane or space figures is deficient in relation to geometric problem solving. This paper examines these aspects, especially in relation to plane and space problem solving in elementary levels. Firstly we propose the analysis frame to investigate a visualization process for plane problem solving and a visualization ability for space problem solving. Nextly we select 13 elementary students, and observe closely how a visualization process is progress and how a visualization ability is played role in geometric problem solving. Together with these analyses, we propose concrete examples of visualization ability which make a road to geometric problem solving. Through these analysis, this paper aims at deriving various discussions about visualization in geometric problem solving of the elementary mathematics.