• Geomechanics and Engineering
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• v.17 no.3
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• pp.287-294
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• 2019

The finite element method (FEM) is widely used to evaluate the seismic performance of pile-supported buildings. However, there are problems associated with modeling the pile end resistance using the FEM, such as the dependence on the mesh size. This paper proposes a new method of modeling around the pile tip to avoid the mesh size effect in two-dimensional (2D) analyses. Specifically, we consider the area of influence around the pile tip as an artificial constraint on the behavior of the soil. We explain the problems with existing methods of modeling the pile tip. We then conduct a three-dimensional (3D) analysis of a pile in various soil conditions to evaluate the area of influence of the soil around the pile tip. The analysis results show that the normalized area of influence extends approximately 2.5 times the diameter of the pile below the pile tip. Finally, we propose a new method for modeling pile foundations with artificial constraints on the nodal points within the area of influence. The proposed model is expected to be useful in the practical seismic design of pile-supported buildings via a 2D analysis.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.2
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• pp.127-142
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• 1990

Comparative studies on the quality of life, a new research specialization,have emerged only in recent years and are experiencing vigorous development in many parts of the world This study is a two year phasing-in project carried out by a jointed research team between Seoul National University and Tokyo University. As the first study of the project series, the aim of the study is to learn how different the quality of life(QOL) between Seoul and Tokyo and how the students of both cities assign the relative weights to parameters of the quality of life in their cities. The study also attempts to illustrate the current state of the art in this new field. Seoul and Tokyo are located very closely bur their physical, socia-economic and cultural aspects are not the same but rather different. Here is our interest and the reason why we started out study. The study is divided into the following two principal parts: (1 ) The survey of the variables influencing the puality of life in Seoul and Tokyo (2) The survey of the attitude of students towards the relative importance of parameter of the quality of life in Seoul and Tokyo. The researches of the variables were carried out utilizing the existing official statistics derived from 1988 Seout Statistical Year Book and 1987 Tokyo Statistical Year Book. Therefore, the choice of indicators was largely limited to data that had been compiled in two yearbooks. The attitude surveys of students were carried out by interview. The questionnaire consists of a face sheet and a question which is designed to produce information on the relative importance of the parameters by the paired comparison method.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.390-392
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• 2003

Video mosaicing techniques have been widely used in virtual reality environments. Especially in GIS field, video mosaics are becoming more and more common in representing urban environments. Such applications mainly use spherical or panoramic mosaics that are based on images taken from a rotating camera around its nodal point. The viewpoint, however, is limited to location within a small area. On the other hand, 2D-mosaics, which are based on images taken from a translating camera, can acquire data in wide area. The 2D-mosaics still have some problems : it can‘t be applied to images taken from a rotational camera in large angle. To compensate those problems , we proposed a novel method for creating video mosaics in 3D space. The proposed algorithm consists of 4 steps: feature -based optical flow detection, camera orientation, 2D-image projection, and image registration in 3D space. All of the processes are fully automatic and successfully implemented and tested with real images.

• Korean Journal of Health Education and Promotion
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• v.1 no.1
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• pp.119-124
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• 1999

Before considering health promotion programs carried out in Japan, I would like to explain a summary of today's health conditions of Japan for a while. Current major concern in public health world as well as political or economic world is an aging society. To say more precisely, it would be an aging society with relatively small children's population. Estimated total population is 126,166,000 in 1997. Among these, almost 10％ population loves in Tokyo Metropolitan Area. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.34-37
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• 2002

Freestanding azobenzene-containing liquidcrystalline network (LCN) films. with macroscopic uniaxial molecular alignment were prepared by insitu photopolymerization. By polarizing microscopy, fiber-like structures aligned in one direction were observed. Furthermore, with a confocal laser scanning microscope (CLSM), it was confirmed that the fiber-like structures were formed even in the bulk of the LCNs. Upon UV light irradiation to cause trans-cis photoisomerization of the azobenzene molecules, the LCNfilms underwent a significant and anisotropic bending toward the irradiation direction of UV light. When the bent LCNfilms were exposed to Vis light, unbending of the LCN films immediately took place and the initial flat LCN films were restored. This bending and unbending behavior of the LCN films could be repeated just by changing the wavelength of the irradiation light. It was suggested that the bending was induced by an absorption gradient which produced a volume difference between the front surface area and the bulk of the network films.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.23-27
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• 2008

As a biofuel source, direct photosynthetic/metabolic biofuel cells (DPBFC) use cyanobacteria whose photosynthesis and metabolization reactions can convert light energy to electricity, In our previous work, we fabricated a prototype micro-DPBFC that could generate a peak current density of $36{\mu}A/cm^{2}$ and a maximum power density of $270nW/cm^{2}$. In this study, we improve on the previous results by using carbon micro electromechanical systems (C-MEMS), formed from the pyrolysis of patterned photoresist, to fabricate carbon electrodes of an arbitrary shape and controlled porosity to increase the surface area. With these new C-MEMS electrodes, the maximum power density of the micro-DPBFC was $516nW/cm^{2}$, a performance twice as good as the results of our previous work.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1028-1031
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• 2009

High quality poly-SiGe thin films were prepared on 6-inch substrates using Reactive-thermal CVD with $Si_2H_6$ and $GeF_4$ around at $500^{\circ}C$ directly. Its thickness uniformity was ~ 3% on the entire substrate area. N-channel mobility of ~30 nm thick bottom-gate TFTs exceeded 20 $cm^2$/Vs without any further crystallization.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2007.10b
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• pp.99-104
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• 2007

With their deity groves, Japanese Shinto shrines form unique green spaces. Further, many shrines are located between a settlement and the rural or natural environment. This location relates to the nature-worship of the Shinto tradition. However, when visiting present shrine precincts, it gives the impression that their original landscape location and green space is impaired by urban changes. This study focuses on the point how the scenic condition of district shrines at the fringe of Tokyo is challenged in the present, and presents an example of a successful preservation in the urban area. The key point of such preservation is that it goes beyond the shrine precinct itself. If there still exists a natural or beautiful scenery next to a shrine with some distinct historical or religious relationship, both shrine and scenery should be preserved together.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1115-1117
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• 2003

The information about transactions of real estate has tended to be not open. Therefore, it has been difficult for individuals to judge the proper price of each real estate. In the course of time several studies have been conducted on proposing criterions for judging the proper price of real estates. As to office buildings and apartments, it is proved techniques required for making criterions have been achieved to a certain extent. Therefore, this research aims to make methods that propose to consumers reliable criteria for judging the proper price of detached houses. The methods are based on hedonic price method and micro-level spatial elements peculiar to detached houses are considered.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.3
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• pp.176- 184
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• 2010

A low-power inductorless 1:4 DEMUX and a 4:1 MUX for a 90 nm CMOS are presented. The DEMUX can be operated at a speed of 25 Gb/s with the power supply voltage of 1.05 V, and the power consumption is 8.9 mW. The area of the DEMUX core is $29\;{\times}\;40\;{\mu}m^2$. The operation speed of the 4:1 MUX is 13 Gb/s at a power supply voltage of 1.2 V, and the power consumption is 4 mW. The area of the MUX core is $30\;{\times}\;18\;{\mu}m^2$. The MUX/DEMUX mainly consists of differential pseudo-NMOS. In these MUX/DEMUX circuits, logic swing is nearly rail-to-rail, and a low $V_{dd}$. The component circuit is more scalable than a CML circuit, which is commonly used in a high-performance MUX/DEMUX. These MUX/DEMUX circuits are compatible with conventional CMOS logic circuit, and it can be directly connected to CMOS logic gates without logic level conversion. Furthermore, the circuits are useful for core-to-core interconnection in the system LSI or chip-to-chip communication within a multi-chip module, because of its low power, small footprint, and reasonable operation speed.