• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.53 no.4
• /
• pp.237-246
• /
• 2004

The advantages of the Magnetic Fluid Linear Pump(MFLP) is that this device could Pump the non-conductive. non-magnetic liquid such as Insulin or blood because of the segregation structure of the magnetic fluid and pumping liquid. In this device. the sequential currents are needed to Produce pumping forces so that Pumping Forces and Pumping speed mainly depend on the current Patterns. The excessive forces at Pumping moment could cause the medical shock, and weak forces at intermediate moment could cause the back flow or the pumping liquid. So the ripples of the pumping forces need to be reduced for the medical application. In this research, the driving characteristics in the MFLP by operating current is analysed. The change of magnetic fluid surface according to the driving currents could be obtained be magneto-hydrodynamic analysis so that Pumping fortes could be computed by integration of the surface moving to the pumping direction at each moment. The actual MFLP with 13mm diameter was made and tested for experiments. The effects of driving current and frequency on the pumping forces and pumping speed were analyzed and compared with experimental measurements.

• Fire Science and Engineering
• /
• v.30 no.4
• /
• pp.82-87
• /
• 2016

The ventilation system for the efficient operation of the building services systems in the ventilation plan of super high-rise buildings is used to combine smoke control systems. This study evaluated models of super high-rise buildings with four basement levels and 59 stories and investigated the pressure distribution of each floor by the smoke driving forces by numerical analysis. The smoke driving forces on the building of analytical model was analyzed to determine the effects of the ventilation plan and smoke control plane. In addition, when a combination with ventilation and smoke control of the kitchen ventilation damper in the ventilation plan of analysis model building was designed based on the these results, the relationship between the opening and closing force of the damper and smoke driving combined forces to act on the design pressure of the damper by a motion analysis simulation. The driving units of the damper were selected from the analytical results.

• Journal of Mechanical Science and Technology
• /
• v.14 no.1
• /
• pp.30-38
• /
• 2000

This paper presents a framework how to estimate crack driving forces in terms of crack-tip opening displacement and J-integral for mismatched dissimilar joints with interface cracks. The mismatch in elastic, thermal, and plastic hardening properties is not considered, but the mismatch in plastic yield strengths is emphasized here. The main outcome of the present work is that the existing methods to estimate crack driving forces for homogeneous materials can be used with slight modification. Such modification includes (i) mismatch- corrected limit load solutions, and (ii) evaluating the contribution of each material in dissimilar joints to the total crack driving force, which depends on the strength mismatch of the dissimilar joints.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.6
• /
• pp.871-883
• /
• 1997

Kinetodynamics of a cam driving slider mechanism consists of kinematic analysis and force analysis. The kinematic analysis is to determine the kinematic characteristics of a cam driving mechanism and a slider mechanism. The force analysis is to determine the joint forces of links, the contact forces of the cam and follower, and the driving torque of a main shaft. This paper proposes a close loop method and a tangent substitution method to formulate the relationships of kinematic chains and to calculate the displacement, velocity and acceleration of the cam driving slider mechanism. Also, and instant velocity center method is proposed to determine the cam shape from the geometric relationships of the cam and the roller follower. For dynamic analysis, the contact force and the driving torque of the cam driving slider mechanism are calculated from the required sliding forces, sliding motion and weight of the slider.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2004.04a
• /
• pp.184-190
• /
• 2004

Over the last few years, there has been a growing interest in quantitative representation of the weld pools in order to relate the processing conditions to the driving forces of the weldment produced and to use this information for the optimization of the welding process. A theoretical model offers a powerful alternative to check the physical concepts of the welding process and the effects of driving forces. To solve this problem, a 2-D thermo-fluid model were eve loped for determining temperature and velocity distribution for the GMA welding process.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.398-401
• /
• 2003

Along with rapid changes and increasing competitions of the global market, a country with advanced technology can gain competitiveness edges. The Korean government recently announced 'Strategic Plan for the Next Generation Driving Forces Industry' in order to respond this global challenges. However, it appears that the construction industry has been put out from the discussions. It can be argued that considering the size and contributions of the industry to the national economy, driving engines for the industry should be considered and identified. The objective of this paper is to propose the criteria of driving engines for the construction industry based on the analysis of the common characteristics of 6T industries' driving forces as recently announced.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1997.10a
• /
• pp.76-85
• /
• 1997

Recently, bent-axis-type axial piston pumps drived by rod being in extensively used in the world, because of simple design, lightweight, effective cost. So, to guarantee the quality of bent-axis-type axial piston pumps drived by rods, it is necessary to know chracteristics of the forces applied to rods and the driving mechanism of rods. But, as they perform both reciprocating and spinning motions, it is difficult to understand driving mechanism. In this paper, I explained the theoretical driving mechanisms of cylinder block drived by rods through geometric method and the characteristics of the forces applied to them.

• Journal of Mechanical Science and Technology
• /
• v.17 no.2
• /
• pp.181-186
• /
• 2003

In order to assure the quality of the bent axis design axial piston pumps driven by tapered pistons, it is necessary to know the characteristics of force applied to tapered pistons and the mechanism for driving the tapered pistons. Since they are able to perform both reciprocating and spinning motions in cylinder block, it is difficult to understand the driving mechanismand-tomeasure the forces applied to tapered pistons experimentally In the present study, the theoretical mechanism for driving the tapered pistons is studied by use of the geometric method. The driving area of the tapered pistons is measured by measuring the strain of a cylinder forced against a tapered piston using an electric strain gauge and a slip ring. The forces applied to tapered pistons is also investigated with the change of discharge pressure and the rotational speed. As a results of this investigation, it is concluded that the cylinder block is driven by one tapered piston in a limited area and the driving area is changed due to space angle of the tapered pistons and the swivel angle of the cylinder block. It is also observed that the force applied to tapered pistons increases as the discharge pressure and the rotational speed increase.

• Journal of the Korean Society for Heat Treatment
• /
• v.9 no.4
• /
• pp.243-251
• /
• 1996

Dilatometric experiment and thermodynamic calculation have been performed to determine $M_s$, $A_s$ and driving forces for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation of Fe-Mn alloys. The transformation temperatures($M_s$, $A_s$, $T_o) were decreased with increasing manganese content and were newly formulated as a function of manganese content. Driving force for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation was increased from -75J/mole to -105J/mole with increasing manganese content from 15wt.% to 25wt.%. Transformation temperature hysteresis($A_s-M_s$) was also increased from 50K to 80K with increasing mangenese content from 15wt.% to 25wt.%. The small driving force(-75J/mole~-105J/mole) and small ${\Delta}T$(50K~80K) for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation indicated that Fe-Mn alloys behave like thermoelastic martensitic alloys : We would like to call them semi-thermoelastic martensitic alloys.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.4 no.2
• /
• pp.1-10
• /
• 1996

The objective of this paper is to develop a motion base for the vehicle driving simulator. Kinematic analysis are carried out to obtain maximum strokes and velocities of hydraulic actuators. Hydraulic control forces of the actuators are estimated by inverse dynamic analysis. Finally, an optimal design is performed to find attachment points of the actuators so that control forces are minimized. A control logic for the motion base is developed to make the motion base follow the given reference signals. The control logic is implemented on a digital signal processor(DSP) board.