• 한국전기전자재료학회논문지
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• 제21권3호
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• pp.255-259
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• 2008

Built-in voltage in ITO/$Alq_3$/ Al organic light-emitting diodes was studied by varying a thickness of $Alq_3$ layer using modulated photocurrent technique at ambient condition. A thickness of the $Alq_3$ layer was varied from 100 to 250 nm. From the bias voltage-dependent photocurrent, built-in voltage of the device was able to be determined. The obtained built-in voltage is about 0.8 V irrespective of the $Alq_3$ layer thickness in the device. This value of built-in voltage confirms that the built-in voltage is generated due to a difference of work function of the anode and cathode. The $Alq_3$ layer thickness independent built-in voltage indicates that the built-in electric field in the device is uniform across the organic layer.

• 가정과삶의질연구
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• 제8권1호
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• pp.101-113
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• 1990

Apartment houses are repidly being assimialated into the Korean lifestyle. Little study of space utilization and specificially built-in storage needs has been implemented into design of these apartment units. The purposes of this study were, first, to ascertain attitudes of a select group of Korean housewives(N=250) living in apartments in Seoul toward closets and built-in storage units, and second, to determine the acceptability of proposed alternative plans which include built-in storage facilities by Korean women(N=31) living in the United States. Overall results reflect that built-in closets and storage are highly prized and additional units required in Korean apartment plans. Of the respondents, about 86% thought portable storage bought at marirage would be phased out if more storage was built into Korean apartmemts. Most Korean housewives would perceive the advantages of built-in storage units, and would prefer differentiated built-in storage units to undifferentiat d ones. Yet attitudes were equally split on the aesthetic value of the elimination of the portable storage. Five Korean apartment plans were drawn to scale then altered through the incorporation of additional built-in storage. These altered plans all received greater then 83% preferences to the existing Korean apartment plans. Additional study needs to be undertaken to address the implementation of additional storage in existing units as well as impact the current space planning concepts related to more built-in storage. Consideration needs to be given to the concerns related to aesthetic value of portable units as part of the study process.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제3권5호
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• pp.129-140
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• 2014

기존의 메모리에서 발생하는 다양한 고장들을 검출하기 위한 기법으로 BIST(Built-in self test)가 있고 고장이 검출되면 Spare를 할당하여 수리하는 BIRA(Built-in redundancy analysis)가 있다. 그리고 BIST와 BIRA를 통합한 형태인 BISR(Built-in self repair)를 통해 전체 메모리의 수율을 증가시킬 수 있다. 그러나 이전에 제안된 기법들은 RAM을 위해 제안된 기법으로 RAM의 메모리 구조와 특성이 다른 NAND-형 플래시 메모리에 사용하기에는 NAND-형 플래시 메모리의 고유 고장인 Disturbance를 진단하기 어렵다. 따라서 본 논문에서는 NAND-형 플래시 메모리에서 발생하는 Disturbance 고장을 검출하고 고장의 위치도 진단할 있는 BISD(Built-in self diagnosis)와 고장 블록을 수리할 수 있는 BISR을 제안한다.

• 대한건축학회논문집:구조계
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• 제33권12호
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• pp.99-106
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• 2017

Recently, the condensation and mold problems of apartment buildings has been growing due to high insulation and high air-tightness performance for energy saving. Most of all, occupants in residential buildings has suffered from property damages due to the condensation and mold of built-in furniture. Condensation at built-in furniture were generally found in winter at the of furniture's back panels, adjacent surfaces of wall, floor and ceiling. The aim of paper is to analyze the characteristics of adjacent area around built-in furniture's condensation problem and the thermal environment around the built-in furniture in winter through the field measurements at apartment buildings. In this research, the thermal conditions and surface temperature around the built-in furniture were measured during winter season. In this research, we analyzed thermal conditions for built-in furniture which were applied and not applied auxiliary heating device. In results, it is important to consider increasing surface temperature for using heater and decreasing absolute humidity due to the occupants' behavior around built-in furniture for preventing condensation.

• 한국주거학회논문집
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• 제14권6호
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• pp.15-22
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• 2003

The regeneration of built-up areas is considered as one of the necessary measures for the effectiveness of urban growth management. In this vein, this study explores how to limit the number of people who leaves the built-up areas and to restore the area with the resident. For this, a residential area of the built-up area is analyzed in terms of why people in that area are moving out of the area and who fills in it after all. This study founds that narrow roads in a residential area and the changes in land use from residential purposes to commercial are major forces that push the people in the built-up area. In addition, the lack of welfare facilities, the pavement of roads, and pedestrian roads. education. crime. the lack of interaction between neighbors, and the quality of housing are all emerged contributing the loss of people in the built-up areas. It is recommended that all the factors here should be restored in an appropriate way. Another finding is that those who fill in the built-up area are largely over 50, self-employed, comparably wealthy, and having their own families. Hence, it is advised that the built-up area would be rearranged in order to attract those type of people in there.

• 가정과삶의질연구
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• 제5권2호
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• pp.99-107
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• 1987

The purpose of this study is to examine the remodeling behavior on the apartment built in furniture. The data were collected from 363 residents in Seoul area, living in apartments equipped with built-in furnitures. The major findings are as follows; 1)It was found out that 62-75% of those surveyed did not remodel their built-in furniture and 25-39% remodeled it. The major reasons for remodeling are the inconvenience in storing household items, lack of storage space and dissatisfaction of the design and color. 2)More than 80% of the apartment residents surveyed recognizes the necessity of the built-in furnitures, which were equipped already, in living room, kitchen, bathroom and the entrance area. A strong need is also indicated for the additional built-in furnitures in each bedroom, multi-service room and veranda. 3) This survey also indicated that 63-73% shows no intention of remodeling their built-in furnitures. On the other hand, 27-37% of those surveyed indicates their desire and plan to remodel them.

• Steel and Composite Structures
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• 제28권2호
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• pp.233-250
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• 2018

Back-to-back built-up cold-formed steel un-lipped channel sections are used in cold-formed steel structures; such as trusses, wall frames and portal frames. In such built-up columns, intermediate fasteners resist the buckling of individual channel-sections. No experimental tests or finite element analyses have been reported in the literature for back-to-back built-up cold-formed steel un-lipped channel sections and specially investigated the effect of screw spacing on axial strength of such columns. The issue is addressed in this paper. The results of 95 finite element analyses are presented covering stub to slender columns. The finite element model is validated against the experimental tests recently conducted by authors for back-to-back built-up cold-formed steel lipped channel sections. The verified finite element model is then used for the purposes of a parametric study to investigate the effect of screw spacing on axial strength of back-to-back built-up cold-formed steel un-lipped channel sections. Results are compared against the built-up lipped channel sections and it is shown that the axial strength of un-lipped built-up sections are 31% lesser on average than the built-up lipped channel sections. It was also found that the American Iron and Steel Institute (AISI) and the Australian and New Zealand Standards were over-conservative by around 15% for built-up columns failed through overall buckling, however AISI and AS/NZS were un-conservative by around 8% for built-up columns mainly failed by local buckling.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집
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• pp.14-16
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• 2008

Built-in voltage in organic light-emitting diodes was studied using modulated photocurrent technique ambient conditions. From the bias voltage-dependent photocurrent, built-in voltage of the device is determined. The applied bias voltage when the magnitude of modulated photocurrent is zero corresponds to a built-in voltage. Built-in voltage in the device is generated due to a difference of work function of the anode and cathode. A device was made with a structure of anode/$Alq_3$/cathode to study a built-in voltage. ITO was used as an anode, and Al and LiAl were used as a cathode. A layer thickness of Al and LiAl were 100nm. Obtained built-in voltage is about 1.0V in the Al layer was used as a cathode. The obatined built-in voltage is about 1.6V in the LiAl layer was used as a cathode. The result of built-in voltage is dependent of cathode. We can see that the built-in voltage increase up to 0.4V when the LiAl layer was used as the cathode. These results correspond to the work function of LiAl which is lower than that of Al. As a result, the barrier height for an electron injection from the cathode to the organic layer could be lowered when the LiAl was used as a cathode.

• Wind and Structures
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• 제22권4호
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• pp.503-524
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• 2016

The suitability of Computational Fluid Dynamics (CFD) simulations on the built environment for the purpose of estimating average roughness characteristics and for studying wind flow patterns within the environment is assessed. Urban models of various levels of complexity are considered including an empty domain, array of obstacles arranged in regular and staggered manners, in-homogeneous roughness with multiple patches, a semi-idealized built environment, and finally a real built environment. For each of the test cases, we conducted CFD simulations using RANS turbulence closure and validated the results against appropriate methods: existing empirical formulas for the homogeneous roughness case, empirical wind speed models for the in-homogeneous roughness case, and wind tunnel tests for the semi-idealized built environment case. In general, results obtained from the CFD simulations show good agreement with the corresponding validation methods, thereby, giving further evidence to the suitability of CFD simulations for built environment studies consisting of wide-ranging roughness. This work also provides a comprehensive overview of roughness modeling in CFD-from the simplest approach of modeling roughness implicitly through wall functions to the most elaborate approach of modeling roughness explicitly for the sake of accurate wind flow simulations within the built environment.

• KIEAE Journal
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• 제10권1호
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• pp.97-107
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• 2010

Although aspiration towards quality of life and holistic health has been growing faster in our modern society and the affordance of health in built environment has been more acknowledged, there has been hardly any development on built environment planning and design theory that can be comfortably and confidently used in creating built environment to promote holistic health. Thereby, this study sets out to experimently formulate a composite theory that explains the relationship between health and built environment. The main methodology of this study is literature review and analysis. Theories that have been applied in other similar fields were chosen to be analyzed by health related perspectives and graft those theories onto holistic health viewpoints to compose a comprehensive theory. Selected theories that were considered useful to be analyzed were Lawton's Environment Press Theory, Carp & Carp's Complementary & Congruence Theory, Valins' Activity-based Design Criteria Theory, Atchley's Continuity Theory, Murtha & Lee's User Benefit Criteria Theory, and Alexander's Pattern Language Theory. Characteristics of these theories were compared by their abstractness and concreteness, and the range of application, and analyzed by a holistic health perspective. Then, these theories were comprehensively structuralized and synthesized as a built environment for health theory. This study has its significance in providing a base to develop healthy built environment research further as it introduced a conceptual framework which explains spatial elements in the health functionality point of view.