• International Journal of Fluid Machinery and Systems
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• v.7 no.2
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• pp.60-67
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• 2014

In order to clarify the effect of inlet bellmouth size of semi-opened type axial fan on its performance and flow fields around rotor, fan test and flow field measurements using hotwire anemometer were carried out for 6 kinds of bellmouth size. As results of fan test, the shaft power curve hardly changed, even if the bellmouth size changed. On the other hand, the pressure-rise near best efficiency point became small with the bellmouth size decreasing. Therefore, the value of maximum efficiency became small as the bellmouth size decreased. As results of flow field measurements at fan inlet, the main flow region with large meridional velocity existed near blade tip when the bellmouth size was large. As bellmouth size became smaller, the meridional velocity at fan inlet became smaller and the one at outside of blade tip became larger. As results of flow field measurements at fan outlet, the main flow region existed near rotor hub side.

• Geomechanics and Engineering
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• v.5 no.1
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• pp.57-70
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• 2013

Constant rate of strain (CRS) consolidation tests were conducted for undisturbed Ariake clay samples from three boreholes in Saga Plain of Kyushu Island, Japan. The coefficients of consolidation ($c_{\nu}$) were interpreted from the CRS test results by small- and large-strain theory. Large-strain theory was found to interpret smaller $c_{\nu}$ values and less strain rate effect on $c_{\nu}$ than that by small-strain theory. Comparing the theoretical strain distributions within a soil specimen to those obtained by numerical simulation shows that the small-strain theory can be used only for the dimensionless parameter $c_{\nu}/\dot{\varepsilon}H_0^2{\geq}50$ (where $\dot{\varepsilon}$ is strain rate and $H_0$ is the specimen height), and the large-strain theory can be used for a larger range of strain rates. Applying the criterion to undisturbed Ariake clay with a $c_{\nu}$ value of about $1{\times}10^{-7}\;m^2/s$, it is suggested that the large-strain theory should be adopted for calculating the $c_{\nu}$ value when $\dot{\varepsilon}$ > 0.03%/min.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.4
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• pp.33-43
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• 2011

The purpose of this study is to clearify the architectural pattern of the Dogsedang(讀書堂) and it's characteristics of the Place which based on the historical background of the Saga-reagingsystem(陽假讀書制度) in the early Chosun Dynasty. The Saga-reaging(賜暇讀書) was given vacation to read books for young scholars who serve in a Royal institution chartered an academic society that we call the Giphyunjeun(集賢默). Due to the consciousness of preference about the old Documment on the history of Chosun Dynasty such as, whangchoshillok(朝蘇王朝實錄) and giligie(地理誌) and so on, I could find a clue that would lead to the solution of the problem. So to speak the division into periods about historical background of the Saga-reagingsystem(賜暇讀書制度) is analysed by questionnaire of scholars who is in. By the analysis, there were two types of the Saga-reagingsystem(賜暇讀書制度) and three places in the Dogsedang(讀書堂). Vacation to read books at the single schalor's home is we called jaegadogse(在家讀書), reading area at the temple in the deep mountain district is the Sansadogse(山寺讀書). The first place reading area at the temple in the deep mountain district was the temple of Jinkwan(律寬寺), the second place was the temple of Jangyue(藏義寺) the third was the temple of youngsan(龍山寺) so called the Namhodang(南湖堂). There is a certain difference of viewpoint with each site. These results show that the site of the Dogsedang(讀書堂) has deep consideration in relation with picturesque scenery.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.83-84
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• 2002

For estimation of chain-matching phenomena between normal paraffin as a solvent and straight-chain fatty acid as an additive, the density measurement of n-dodecane, n-tetradecane and n-hexadecane were carried out at oil temperature 313K and pressure up to 1.3 GPa. Their solidification pressure were easily determined by the appearance of molecular crystal, abrupt volumetric contraction and generation of heat of solidification and showed minima under the matching condition. The bulk modulus K of molecular crystal was evaluated using phase diagram. The bulk modulus showed maxima under the each matching condition. The chain matching effect on the bulk modulus beyond the scope of the interfacial phenomena are confirmed.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1460-1464
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• 2003

This paper describes the design and implementation techniques of a generic Internet based telerobotic system. The purpose is to make precious technical information and hands-on experience of the authors widely available for the research community. The paper is based on the telerobotics system that the authors recently implemented between KAIST and Saga University, Japan. In its current functionality, two control modes can be exercised; high-level supervisory control, and low-level supervisory control.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.34-36
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• 1996

For the test of the operating characteristics as a moor, a 20 kVA super conducting synchronous machine with rotating field windings has been made in Saga university, Japan from 1991. Before the load tests of it as a motor, we carried out cooling down tests and measured its machine constants. During the cooling down tests, we found that the rotor itself had no cryogenic problem, but the inlet part for liquid He had one. Though enough liquid He couldn't be accumulated inside the rotor because of this problem, we drove field currents up to 20 A and could acquire the machine constants and V curves of the super-conducting synchronous motor.

• Journal of computational fluids engineering
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• v.10 no.1
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• pp.80-86
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• 2005

In order to control the transonic flow field with a shock wave, a condensing flow was produced by an expansion of moist air on a circular bump model and shock waves were occurred in the supersonic parts of the fields. Furthermore, the additional passive technique of shock-boundary layer interaction using the porous wall with a cavity underneath was adopted in this flow field. The effects of these methods on the shock wave characteristics were investigated numerically. The result showed that the flow fields might be effectively controlled by the suitable combination between non-equilibrium condensation and the position of porous wall.

• International Journal of Contents
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• v.13 no.2
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• pp.1-5
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• 2017

Residents under hazard and disaster conditions should be evacuating to the pre-assigned nearest safety facilities, community hall, local schools, friend's houses, etc. in a safety zone, quickly as soon as possible. The small percentage of evacuees shows serious economy class syndrome after the quake, because those people are forced to a stressful dairy evacuee-life in scattered homes and/or in-vehicle, for instance. Then, we consider on supporting evacuees using heart rate variability, Geospatial Positioning System (GPS) and WiFi functions of a smartphone, and Web-server on the Internet to keep their health in good conditions.

• International Journal of Control, Automation, and Systems
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• v.4 no.1
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• pp.17-29
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• 2006

A novel inverse kinematics solution based on the back propagation neural network (NN) for redundant manipulators is developed for online obstacles avoidance. A laser transducer at the end-effctor is used for online planning the trajectory. Since the inverse kinematics in the present problem has infinite number of joint angle vectors, a fuzzy reasoning system is designed to generate an approximate value for that vector. This vector is fed into the NN as a hint input vector rather than as a training vector to guide the output of the NN. Simulations are implemented on both three- and four-link redundant planar manipulators to show the effectiveness of the proposed position control system.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10a
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• pp.753-758
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• 1987

The purpose of ocean thermal energy conversion (OTEC) plant control is to provide stable power efficiently by appropriately regulating the seawater flow rates and the working fluid flow rate under conditions of continually changing seawater temperatures. This paper describes digital control of working fluid flow rate based on an adaptive control theory for the "Imari 2" OTEC plant at Saga University. Provisions have been made for linkage between the software of the adaptive control theory and the hardware of the OTEC plant. In implementing the working fluid flow rate control, if persistency of excitation conditions are lost, the algorithm of identification often exhibits bursting phenomena. To avoid this difficulty, the stopping-and-starting rule for identification was derived and was used for the working fluid flow rate control. Satisfactory control performance was then obtained by using this digital control system.ol system.