• 대한임상약리학회:학술대회논문집
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• 1993.12a
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• pp.27-27
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• 1993

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.5
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• pp.268-273
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• 2017

In this study, nickel hydroxide crystalline powders were synthesized by continuous reaction in the taylor fluid flow using nickel chloride, nickel sulphate and sodium hydroxide as raw materials and compared with those prepared by a conventional batch type reaction. The crystallinity of nickel hydroxide prepared by the Taylor fluid flow reaction was higher than that of nickel hydroxide obtained by batch reaction. The particle size of nickel hydroxide decreased about 2.5 to 3.6 times, and the specific surface area was increased.

• Journal of Power System Engineering
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• v.5 no.4
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• pp.38-43
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• 2001

This paper describes the effect of dynamic characteristics in tube line by external vibration conveying fluid with the power steering system. By the experimental analysis we found out that the factor of system vibration is the fluid-structure interaction of tube line. In fluid-filled tube system we study on the influence that the natural frequency of system and the frequency of wave motion produce upon through experiment. Experiments are modal test, frequency response function in continuous system, and vibrating tests when the system is driving with bolted clamping joint condition. From the results of the experimental studies, we obtained that the natural frequencies of system are very important than the wave induced vibrations. And we found that the tendency of system vibration level was decreased by bolting force, bolting condition and clamping distance.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.111-118
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• 2003

Recently, environmental damage to urban area becomes serious problem due to the exhaust emissions by increasing the number of vehicle. Especially, exhaust emission from diesel vehicles are blown to be harmful to human health and environment. Photoacoustic Spectroscopy system is very useful technology for simultaneous and continuous measurement of the various components of the automotive exhaust gas. In this study, in order to reduce emission gases from automobile, we tried to develop the measurement system of Photoacoustic Spectroscopy. To improve performance of high sensitive Photoacoustic Spectroscopy system for automotive exhaust emissions, the shape of Photoacoustic Spectroscopy cell was optimized to use the flow analysis. And Exhaust emission data of the 1,500cc gasoline engine was fixed the working fluid. The characteristics of fluid flow for cell were analyzed by various conditions in detail.

• Journal of the Korean Society of Safety
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• v.15 no.3
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• pp.45-51
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• 2000

This paper studies the effect of vibrational characteristics of the various tubes analyzed though experiment. By an experiment analysis we found out that the factor of system vibration is fluid-structure interaction of tube line. In fluid-filled tube system we study on the influence that the natural frequency of system and the frequency of wave motion produce upon through three experiments. Three experiments are modal test on each tube, FRF in continuous system, and vibrating tests when the system is driving on. From the results of the experimental studies, we obtained that the natural frequencies of system are very important than wave induced vibrations. and according to the variation of configuration, the frequencies are different each other. And we found that though fluid passed away through the tube, the tendency of system vibration level was similar with the mode shape at the simple system.

• Tribology and Lubricants
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• v.13 no.2
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• pp.27-38
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• 1997

ER clutch is a device using ER fluid, so called "intelligent material" and is a power transmission system controlled with electric field strength. This device responses very rapidly when controlled by rapid and continuous electrical signal and can form a servosystem. Wear, noise and vibration during operation is very low level. This study was undertaken to investigate substitutive possibilities of this ER clutch for existing power transmission mechanism. An analytic relationships using rheological model (so called, 'Bingham plastic model') of ER fluid were developed, and operation constraints and optimum design concepts were constructed. With this relationships, typical responses of ER clutch and effects of changing geometric, kinetic parameters of ER clutch and ER fluid properties were described. In conclusion, compared with existing mechanisms, an excellent performance of ER clutch was confirmed.confirmed.

• 한국해양학회지
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• v.30 no.4
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• pp.355-364
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• 1995

A heavy fluid is injected to a rotating cylindrical container of flat or inclined bottom filled with homogeneous lighter fluid. Continuous flow-in and spreading patterns over the bottom of the container are observed and at the same time upper-layer motions induced by the movement of the heavy fluid are traced by thymol blue solution. Regardless of bottom geometry, the injected denser fluid is deflected toward "western wall" and continuous its path along the boundary with radial spreading which occurs in the bottom boundary layer to make a quite asymmetric flow. When the bottom contains a slope(${\beta}$-plane), increased pressure gradient causes the fluid move faster to produce a stronger Coriolis force. This makes the width of the flow narrower than that of f-plane. But, when the denser flow reaches the southern part of the container, a local-depth of denser fluid increases (much greater than the Ekman-layer depth) such that the spreading velocity along the wall is reduced and the interfacial slope increases to make the upper-layer adjust geographically to have oppositely directed upper-layer motion along the interfacial boundary. The role of the denser fluid in terms of vorticity generation in the upper-layer is such that it produces local topographic effect over the western half of the container and also induces vortex-tube stretching which is especially dominant in the f-plane.

• Advances in nano research
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• v.13 no.4
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• pp.341-350
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• 2022

The continuous elements method, also known as the dynamic stiffness method, is effective for solving structural dynamics problems, especially over a large frequency range. Before applying this method to fluid-structure interactions, it is advisable to check its validity for pure acoustics, without considering the different coupling parameters. This paper describes a procedure for taking wave propagation into account in the formulation of a Dynamic Stiffness Matrix. The procedure is presented in the context of the harmonic response of acoustic pressure. This development was validated by comparing the harmonic response calculations performed using the continuous element model with the analytical solution. In addition, this paper illustrates the application of this method to a simple compressible flow problem, since it has been applied solely to structural problems to date.

• Journal of muscle and joint health
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• v.23 no.2
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• pp.84-94
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• 2016

Purpose: This research aimed to identify levels of nurses' perception and practice of fluid intake and output (I & O) measurement and to explore the relationship between perception and practice of it. Methods: Using a cross-sectional survey design, 195 nurses who practiced fluid I & O measurement were recruited from a general hospital. Nurses who agreed to participate in this study completed a structured study questionnaire to assess their levels of perception and practice of fluid I & O measurement. Results: A level of perception of I & O measurement was high (3.46 points out of 5), and scores for 3 subdomains of I & O (importance, accuracy, and efficacy) were evenly high. The level of practice of I & O was fairly high (3.76 points out of 5). Perception and practice of I & O were highly correlated (r=.73, p<.001). Conclusion: Nurses seem to have higher levels of perception and do practice fluid I & O measurement correctly. In order to have reliable and valid I & O measures, nurses need to have continuous education on I & O measurement based on clinical guideline to utilize it as an invaluable clinical instrument.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.67-75
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• 2008

In construction facilities such as bridges, the fluid boundary layer(or water film) is formed at the structure-soil interface by the inflow into the system due to rainfall or/and rising ground-water. As a result, the structure-soil interaction(SSI) state changes into the structure-fluid-soil interaction(SFSI) state. In general, construction facilities may be endangered by the inflow of water into the soil foundation. Thus, it is important to predict the dynamic SFSI responses accurately so that the facilities may be properly designed against such dangers. It is desired to have the robust tools of attaining such a purpose. However, there has not been any report of a method for the SFSI analyses. The objective of this study is to propose an efficient method of finite element modelling using the new interface element named hybrid interface element capable of giving reasonable predictions of the dynamic SFSI response. This element enables the simulation of the limited normal tensile resistance and the tangential hydro-plane behaviour, which has not been preceded in the previous studies. The hybrid interface element was tested numerically for its validity and employed in the analysis of SFSI responses of the continuous bridge subjected to seismic load under rainfall or/and rising ground-water condition. It showed that dynamic responses of the continuous bridge resting on direct foundation may be amplified under rainfall condition and consequently lead to significant variation of stresses.