• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.5
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• pp.339-349
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• 2020

Double-leaf blast-resistant doors consisting of steel box and slab are application-specific structures installed at the entrances of protective facilities. In these structural systems, certain spacing is provided between the door and wall. However, variation in the boundary condition and structural behavior due to this spacing are not properly considered in the explosion analysis and design. In this study, the structural response and failure behavior based on two variables such as the spacing and blast pressure were analyzed using the finite element method. The results revealed that the two variables affected the overall structural behavior such as the maximum and permanent deflections. The degree of contact due to collision between the door and wall and the impact force applied to the door varied according to the spacing. Hence, the shear-failure behavior of the concrete slab was affected by this impact force. Doors with spacing of less than 10 mm were vulnerable to shear failure, and the case of approximately 15-mm spacing was more reasonable for increasing the flexural performance. For further study, tests and numerical research on the structural behavior are needed by considering other variables such as specifications of the structural members and details of the slab shear design.

• Korean Institute of Interior Design Journal
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• v.25 no.1
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• pp.181-191
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• 2016

The purpose of this study is to analyze affordance of façade design by extracting analysis elements of affordance in façade design domestic five-star hotels. The subjects of this study were 88 domestic five-star hotels; we selected literature review and case study as methodology. The analysis elements included mass forms, exterior colors, window frame patterns, exterior characteristics, and door types based on the visual perception factors of façade design from the concept of affordance. The results of the study were as follows. First, the mass forms were divided into stackable, integral, and connection types, and stackable type was most frequent. Second, exterior colors were divided into achromatic, red, yellow, and opaque color parts, and the achromatic parts were most frequent. Third, the window frame patterns were divided into grid, irregular, full, horizontal, and vertical windows, and grid windows were most frequent. Fourth, the exterior characteristics were divided into formative mass, horizontal partition, design contrast, tiled roof, and facility connection, and the formative mass was most frequent. Fifth, the door types were divided into porch, piloti, and wall type, and porch was most frequent. The results of this study showed that the façade design elements such as mass forms, exterior colors, window frame patterns, exterior characteristics, and door types intentionally contained affordance.

• Transactions of Materials Processing
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• v.9 no.6
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• pp.653-662
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• 2000

Wrinkling is one of the major defects in sheet metal products together with tearing, springback and other geometric and surface defects. The initiation and growth of wrinkles are influenced by many factors such as stress ratios, mechanical properties of the sheet material, geometry of the workpiece, contact condition, etc. It is difficult to analyze the wrinkling initiation and growth considering all the factors because the effects of the factors are very complex and the wrinkling behavior may show a wide scatter of data even for small deviations of factors. The finite element analyses of the wrinkling initiation and growth in the sheet metal forming process provide the detailed information about the wrinkling behavior of sheet metal. The direct analyses of the wrinkling initiation and growth, however, bring about a little difficulty in complex industrial problems because it needs large memory size and long computation time. In the present study, therefore, a global-local analysis technique is introduced for the computational efficiency. Through the analysis of wrinkling in the door inner stamping process, the efficiency of the global-local analysis technique is investigated.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1473-1480
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• 2008

This article deals with a case study on evaluating RAM(Reliability, Availability and Maintainability) performance of the door systems. The RAM performance is analysed based on the field data. The definition and category of failures of the door systems are presented and reliability for each categories is predicted with field data. MTTR(Mean Time To Repair) is estimated through the replacement time of line replaceable units(LRU). The availability is predicted based on the estimated reliability and maintainability.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.97-107
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• 2017

In the field of automatic door, the infrared rays and microwave sensor are much used as the important components in charge of the motor's operation control of open and close through the incoming signal of object recognition. In case of existing system that the sensor of the infrared rays and microwave are applied to the automatic door, there are many malfunctions by the infrared rays and visible rays of the sun. Because the automatic doors are usually installed outside of building in state of exposure. The environmental change by temperature difference occurs the noise of object recognition detection signal. With this problem, the hardware fault that the detection sensor is unable to follow the object moving rapidly within detection area makes the sensing blind spot. This fault should be improved as soon as possible. Because It influences safety of passengers who use the automatic doors. This paper conducted an experiment to improve the detection area by installing extra ultrasonic sensor besides existing detection sensor. So, this paper realize the computing circuit and detection algorithm which can correctly and rapidly process the access route of objects moving fast and the location area of fixed obstacles by applying detection and advantages of ultrasonic signal to the automatic doors. With this, It is proved that the automatic door applying ultrasonic sensor is improved detection area of blind spot sensing through field test and improvement plan is proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.88-92
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• 2017

Owing to the depletion of fossil energy, wind power is attracting attention as a promising environmentally friendly alternative energy source, because it is abundant, renewable, and non-polluting. Wind turbines are divided into horizontal axis wind turbines (HAWTs) and vertical axis wind turbines (VAWTs) according to the direction of the rotating shaft. VAWTs have a low power generation efficiency, but are not affected by the wind direction and, thus, no yaw system is required and their structure is simple. Small VAWTs are attracting much attention because they can generate power even at low wind speeds. In this study, the output voltages and output currents of small VAWTs with gyromill type, hinge type and double door type blades capable of generating power even at low wind speeds were analyzed at variable wind speeds in the range of 1~11 m/s. At the maximum wind speed of 11m/s, the application of the double door type blades achieved 67% and 9% higher wind turbine output voltages than that of the gyromill type and hinge type blades, respectively. As regards the wind turbine output currents, the application of the double door type blades gave rise to 93% and 5% higher results than that of the gyromill type and hinge type blades, respectively. Through this study, the excellent output characteristics and commercialization potential of the double door type blades, which can generate power both at low and high wind speeds, were confirmed.

• Land and Housing Review
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• v.5 no.4
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• pp.325-332
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• 2014

The purpose of this study was to measure the airtightness and Air-Flow Performance for 7th house of small apartment houses adopted window frame-type natural ventilation. All window and living room door is provide with window frame-type natural ventilation, and there is provide with manual controller. As the object of measurement, the 6th type small apartment houses with area of $33m^2$ to $51m^2$ was selected. airtightness performance was measured at the front door using Blower door system. We measured ventilation rate per hour on 50Pa pressure different between inside and outside by the 1st to 6th cases. As a result, when the natural ventilation frame was closed, average amounts are shown as the ventilation rate per hour were 2.27ACH (CASE1). and the result is similar to general apartment house (1.65~4.28ACH). When the natural ventilation frame was open, average amounts are shown as the ventilation rate per hour were 5.87ACH (CASE6). In addition, that's a 3.6ACH increased more than CASE1.

• Applied Microscopy
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• v.40 no.2
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• pp.109-116
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• 2010

Morphology and microstructure of the suction trap in aquatic Utricularia japonica were examined using scanning electron microscopy. Branched stems bear numerous suction traps without root formation. The traps are derived axillary from the node, and their antennae and appendages extend in a peculiar fashion. The trap walls are thin, two-celled, parenchyma tissue and simple, small glands are scattered in both internal and external surface of the trap. The entrance of the trap is surrounded by one pair of dorsal antennae and ventral appendages, where the former guides the prey to the entrance. Trap door is situated below the entrance and numerous sessile and stalked capitate trichomes cover the entrance and even on the door surface. The capitate trichomes are secretory, but four trigger hairs formed on the central areas of the door are not. They are believed to function in activating and tripping the trap door. A specialized region of the threshold come in contact with the lower portion of the door upon closing. The secretory capitate trichomes near this region are responsible for producing and secreting a mucilage-like substance which composes the velum. Two-armed bifid glands are located in the interior side of the threshold, while four-armed quadrifid glands are considerably numerous occurring over the entire inner trap wall. Bifid and quadrifid glands develop semi-spherical basal cells that connect them to the inner wall surface. Antennae, trigger hairs, capitate trichomes, bifid and quadrifid glands are more important structures in the carnivory of U. japonica.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.50
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• pp.163-185
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• 2011

The purpose of this paper is to suggest competitiveness promotion factors of korean Parcel Express Service Industry. This study considered in terms of three competitiveness promotion factors which are a firm's subjective factors, a industrial environment factors, and a governmental policy factors. According to analysis results of the factors, a firm's subjective factors(4.07 score) are scored the most ones of competitiveness promotion factors of korean Parcel Express Service Industry, to be compared with a industrial environment factors(3.89 score), with a governmental policy factors(3.76 score). Therefore, first of all, korean Parcel Express Service firms have to promote competitiveness through as follows : (1) speedy meeting to customer's needs, (2) to promote customer service, to reduce delivery lead time, (3) to procure reliability of Parcel Express Service with customers mutually, (4) strategy of global Parcel Express Service.

• Journal of Arbitration Studies
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• v.29 no.3
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• pp.99-119
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• 2019

In recent times, the volume of cross-border e-commerce has witnessed an upward trend and has been accompanied by increased disputes, with cross-border e-commerce being characterized mainly by low value and large volume issues. For this reason, Online Dispute Resolution (ODR) was formed to carry out dispute resolutions in cross-border e-commerce. A virtual multi-door ODR platform for small value, cross-border disputes in e-commerce is then proposed in this paper. For a couple of decades, researchers have tried to employ Artificial Intelligence (AI) to Law. However, it turns out that they were faced with a couple of obstacles to integrate AI to Law since it is highly difficult to program AI to process the common sense of a human being. For example, AI cannot assimilate the affective side of a human being, and it is problematic to integrate a human being's common sense into the AI system. Considering this situation, this study puts forward an ODR model for cross-border e-commerce in the evolutionary perspective.