• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.138-143
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• 2010

This paper presents the analysis, the fabrication and the test results of a micro passive gas pressure regulator to keep the outlet pressure costant even for a widely-varying inlet pressure. This device is to regulate the outlet pressure according to the applied reference pressure based on the pressure balancing mechanism of the structure including a membrane and a valve. This regulator consists of four layers; a bulk-micromachined silicon substrate, a sandblasted glass substrate, a PDMS valve seat layer and a glass valve layer. The device size is $10\times13\times1.7 mm3$. The device was fabricated by micromachining. The characteristic of the device was analyzed and tested. The characteristic of the fabricated pressure regulator is similar to that obtained from the analysis. The pressure regulator of this paper is feasible for portable systems and miniature drug delivery systems.

• Journal of TMJ Balancing Medicine
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• v.8 no.1
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• pp.6-10
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• 2018

In order to propose a fundamental and appliable theories for balancing therapy of temporomandibular joint (TMBT), evolutionary proofs and up-down theories in evolutionary biology and Korean medicine were investigated. Balancing therapy of temporomandibular joint treats disorder and diseases of the whole body through straightening of the abnormal linking between temporomandibular joint and axis. Although the mechanism of this therapy contains many merits like multicellular integrity and coadjustment, ease of balance and alert forward mobility by the bipedal stepping and evolution to Homo sapiens, increasing disadvantages of balancing pressure of right and left in the lengthened perpendicular axis and the balancing load of temporomandibular joint and axis following the reactional change of dental occlusion are deeply related and considered in this therapy. As for up-down theory, crossing of heavenly qi and earth qi centering on cervical joint is presented as the first mechanism for TMBT, and the other ones like in-out and up-down qi activity of tripple energizer, up-down of essence-qi-spirit in the three backbone barrier and three cinnabar field, up-down of yin-yang-water-fire of viscera and bowels can be related too.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.686-692
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• 1999

For the purpose of increasing compressed air pressure higher than 30bar lightening weight and decreasing installation area of air compressor used for shipboard and industrial power plant it is necessary to arrange its cylinders as a w-type or v-type construction multi-stage compression pro-cess more than two stages and to increase its operation speed higher than 1200rpm In this recip-rocating type air compressor operated in high speed having a crank mechanism and complicate cylinder arrangement there is a vibration problems which can be solved by balancing its recipro-cating parts with balance weight and approriate arranging of cylinder's arrangement angles.

• Journal of Biomedical Engineering Research
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• v.18 no.2
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• pp.157-166
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• 1997

Postural balancing in human is known to be maintained by the complex mechanism coupled with cerebellum, equilibrium organ of ear, proprioception and other various organs. We developed a Computerized Balance Evaluation and Training system(COBET system) to evaluate postural control and to rehabilitate geriatrics and disabled patient. In addition, 55 normal adult were tested to investigate the influencing factors on balancing posture. For the analysis of static postural sway, areas of the moving center of pressure were calculated under 8 different positions of subjects. And subjects were also asked to follow the visual targets on monitor for the evaluation of the dynamic postural sway. In comparison of the first and the second sets of tests, there was test-retest reliability($\textit{p}$< 0.05). The controllability of the static pmtwn sway was decreased as the ages of subjects increase. When the ages of subject are over 60, the controllability was significantly decrease4 The dynamic postural sway was significantly greater in the age groups of 7th and 8th decade than the younger groups. It is concluded that COBET system is a reliable system in the evaluation of postural sway. The COBET system is considered to be a valuable training modality for the disabled patients as well as the elderly.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.53-53
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• 2015

Basin-scale motions in a stratified lake rely on interactions of spatially and temporally varying wind force, bathymetry, density variation, and earth's rotation. These motions provide a major driving force for vertical and horizontal mixing of inorganic and organic materials, dissolved oxygen, storm water and floating debris in stratified lakes. In Lake Tahoe, located between California and Nevada, USA, basin-scale circulations are obviously important because they are directly associated with the fate of the suspended particulate materials that degrade the clarity of the lake. A three-dimensional hydrodynamic model, ELCOM, was applied to Lake Tahoe to investigate the underlying mechanisms that determine the characteristics of basin-scale circulations. Numerical experiments were designed to examine the relative effects of various mechanisms responsible for the horizontal circulations for two different seasons, summer and winter. The unique double gyre, a cyclonic northern gyre and an anti-cyclonic southern gyre, occurred during the winter cooling season when wind stress curl, stratification, and Coriolis effect were all incorporated. The horizontal structure of the upwelling and downwelling formed due to basin-scale internal waves found to be closely related to the rotating direction of each gyre. In the summer, the spatially varying wind field and the Coriolis effect caused a dominant anti-cyclonic gyre to develop in the center of the lake. In the winter, a significant wind event excited internal waves, and a persistent (2 week long) cyclonic gyre formed near the upwelling zone. Mechanism of the persistent cyclonic gyre is explained as a geostrophic circulation ensued by balancing of the baroclinc pressure gradient (or baroclinic instability) and Coriolis effect. Topographic effect, examined by simulating a flat bathymetry with constant depth of 300m, was found to be significant during the winter cooling season but not as significant as the wind curl and baroclinic effects.