• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.647-650
• /
• 2001

In case of bent axis type axial piston hydraulic pump or motor, hydrostatic bearing used to achieve the lubrication effect on the mechanical sliding contact areas between the following pairs ; piston shoe and swash plate, valve plate and cylinder block, piston and cylinder block, etc. In this research, we designed two pairs of spherical ball joint in witch connecting rod piston end. The one is not hydrostatic bearing, the other is designed with spherical hydrostatic bearing in point of view minimum pumping power loss. By varying supply pressure on the piston, we can know that it is possible to reduce the friction torque by using hydrostatic bearing designed one. Finally, by comparing the results of driving torque between the two models, it was verified that the spherical hydrostatic bearing is well designed.

• IMMUNE NETWORK
• /
• v.12 no.2
• /
• pp.41-47
• /
• 2012

Contemporary studies illustrate that peripheral injuries activate glial components of the peripheral and central cellular circuitry. The subsequent release of glial stressors or activating signals contributes to neuropathic pain and neuroinflammation. Recent studies document the importance of glia in the development and persistence of neuropathic pain and neuroinflammation as a connecting link, thereby focusing attention on the glial pathology as the general underlying factor in essentially all age-related neurodegenerative diseases. There is wide agreement that excessive glial activation is a key process in nervous system disorders involving the release of strong pro-inflammatory cytokines, which can trigger worsening of multiple disease states. This review will briefly discuss the recent findings that have shed light on the molecular and cellular mechanisms of glia as a connecting link between neuropathic pain and neuroinflammation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.112-112
• /
• 2010

The purpose of development is to localize a connector for connection of cable and GIS for underground transmission system. The cable connector for GIS provides electrical insulation of GIS housing part and makes connection of ultra high voltage electrical apparatus and power cable by controlling electrical stress between electrodes of power cable termination. Generally Korean switchgear makers are using a connector for GIS made by foreign companies. We manufactured sample by best structure design of great capacity conductor connecting part and then modified the design by analysis of shape and section. We completed the suitable sample for current cycling test condition of conductor connecting part sample and ensured surge characteristics of line by short-time current test.

• Journal of Ocean Engineering and Technology
• /
• v.20 no.6 s.73
• /
• pp.75-81
• /
• 2006

In this study, the dynamic response of the umbilical cable in a deep-water unmanned underwater vehicle system was analyzed. In order to analyze the forces acting on the cable, the launcher and umbilical cable were modeled by the simple 1-D mass-spring system. Damping and dynamic analysis was carried out by a direct time integration scheme using the $Newmark-{\beta}$ method with inverse iteration procedure, considering the nonlinear drag forces acting on the launcher. The obtained results of the present study can be used for the design of connecting the structure of the launcher and cable of the UUV system.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.6 no.4
• /
• pp.44-49
• /
• 2007

In this paper, propose an optimal design to improve the mechanical efficiency of gate valve made by forging method. In order to design the experiments using table of orthogonal array and optimization design is conducted as application of real response model to Taguchi method based approximation model using computer simulation. Also, from verification of the response model with optimized results was confirmed that usefulness and reliance of application Taguchi method to structural optimum design using finite element analysis and equation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.895-898
• /
• 2001

This paper presents an optimization cutting speed(OCS) program developed to improve the machining precision and tool life in high speed machining using ball end milling. This program optimized the cutting speed that is changing at any time in free surface machining of an automobile part like a connecting load die. The technique of optimization cutting speed makes the CAD/CAM-generated NC code go through a reverse post process, conducts cutting simulation, and obtain the effective tool diameter of the ball end milling. Then it changes the spindle revolution to within the range of critical cutting speed fit for the material of the workpieces depending upon the effective tool diameter. In this study, the machining precision and tool life were compared for the two connecting load dies processed using the general cutting method and the proposed optimization cutting speed technique, respectively.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1605-1608
• /
• 2003

A unstructured tetrahedral mesh generation algorithm has been presented. To make better meshes in interior region using an advancing front technique, a connecting operator has been developed in addition to the existing operators. Before applying digging operators that generate new nodes inside of a meshing region, a connecting operator is employed that uses existing nodes which satisfy certain conditions for producing well-conditioned elements if possible. By introducing this new operator, tetrahedral meshing process becomes more robust and produces better quality of meshes.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.8 s.197
• /
• pp.50-57
• /
• 2007

In this paper, two types of novel planar Translational Parallel Manipulators (TPMs) by using parallelogram mechanism are conceived. One is made up of two Pa-P (Parallelogram-Prismatic) legs connecting the base to the moving platform. The other consists of two P-Pa legs, which is the kinematic inversion of the former. Since connecting links in a parallelogram mechanism are subject to only tensile/compressive load and all the heavy actuators are mounted at the base, the proposed manipulators can be applied for planar positioning/assembly tasks requiring high stiffness and high speed. The position, velocity, and statics are analyzed, and the design methodology using prescribed workspace and velocity transmission capability is presented. Finally, two types of prototype manipulators have been developed.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.33 no.7
• /
• pp.512-519
• /
• 2009

Flow pulsation in the gap connecting with two parallel channels is investigated by RANS and URANS approaches. The two parallel channels are connected by a small channel called for a gap. The parallel channels are designed to have different cross section area with its ratio of 0.5. Computations are conducted using a CFX 11.0 code. The bulk Reynolds number is 60,000. Predicted results are compared with the previous experimental data. Mean velocity profile at the center of gap region are compared with experiments for its validation. Spectral analysis on the lateral velocity in the center of the gap was performed. Auto correlation for the axial-flow velocity pattern was presented. The unsteady structure of the flow pulsation was visualized in the region of the gap in the parallel channel.

• Journal of the korean society of oceanography
• /
• v.34 no.4
• /
• pp.231-235
• /
• 1999

A simple analytic model for estimating the volume transport of the Tsushima Current is considered by assuming that the transports through the connecting channels, the Korea and Tsugaru Straits, are geostrophically controled. The model gives a much simpler form of solution than that by Minato and Kimura (1980). It depends no longer on the geometry of the marginal sea and on the thickness of western boundary layer relative to the dimension of the ocean, but considers the geometry of the connecting channels ignored by Nof (1993). The external parameters turn out to be the oceanic meridional sea level difference between the two channels, the depth of the channels and the meridional position of the marginal sea. For typical value of the depth ratio of the channels to the ocean, the model gives an estimate of the Tsushima Current transport of acceptable magnitude.