• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2005.10a
• /
• pp.448-452
• /
• 2005

Punching/blanking/shearing is among the oldest and most frequently used sheet metal forming process. We have developed the shear device for burrless cutting using the micro wire. Since the burr minimization and fine shear plane, this paper is a study on the effect of the shear angle and clearance of the cutter-cutter. And, we confirm the tendency of the shear plane. It is impossible to completely remove the burr in the shearing process. In order to minimize the burr size and fine shear plane, we have accomplished the various experiment conditions such as the shear angle and clearance. Despite the quality of shear plane is not good enough yet, it is possible to make the burr minimization and fine shear plane by the optimization of process parameters.

• Journal of the Korean Society of Tobacco Science
• /
• v.22 no.1
• /
• pp.58-60
• /
• 2000

In order to improve the loading efficiency in bulk dryer for the flue-cured tobacco leaves, a new hanger device was developed. It consists of two layers frame, in which large volume of the harvested leaves could be simply loaded. As the results of experiments with new hanger device, labor hours for loading could be saved by 34 % as compared with those in conventional 3 layers hanger, and loading capacity increased by 36%. The weight of hanger could be also reduced by 0.6kg compared to conventional 3.4kg, showing possibility of cost reduction for the developed hanger device with saved number of punching the rolled steel panels.

• Transactions of Materials Processing
• /
• v.16 no.4 s.94
• /
• pp.313-316
• /
• 2007

The purpose of this paper is the development of measurement algorithm for green-sheet based on the digital image processing technique. The Low Temperature Co-fired Ceramic(LTCC) technology can be employed to produce multilayer circuits with the help of single tapes, which are used to apply conductive, dielectric and/or resistive pastes on. These single green-sheets must be laminated together and fired at the same time. Main function of the green-sheet film measurement algorithm is to measure the position and size of the punching hole in each single layer. The line scan camera coupled with motorized X-Y stage is used. In order to measure the entire film area using several scanning steps, an overlapping method is used.

• Proceedings of the KAIS Fall Conference
• /
• 2005.05a
• /
• pp.191-193
• /
• 2005

In this paper new, inverter control system for TG feedback a formula Control was developed. The motor control system with TG feedback controller as an effect of load disturbance, it is very difficult to guarantee the robustness of control system. The function of the implementation we TG feedback type, and temperature scheme. The Inverter Control System approach is based on master-slave control concept. To show validity of the developed new inverter control system, several experiments are illustrated.

• Journal of Sensor Science and Technology
• /
• v.24 no.3
• /
• pp.159-164
• /
• 2015

Solid state electrochemical and chemo-resistive gas sensors have been used widely but can operate only under high temperature. For reducing the power consumption and optimizing the structure of the substrate of these sensors, we conducted device and circuit simulations using the COMSOL Multiphysics simulator. For assessing the effective types of substrate and heat isolation, we conducted three-dimensional thermal simulations in two separate parts; (a) by changing the shape of the contacting holes and (b) punching additional holes on the substrate. Thus, it was possible to achieve high temperature in the sensor end of the substrate while maintaining low power consumption, and temperature in the circuit.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2007.10a
• /
• pp.285-288
• /
• 2007

In the recent years the using of low-density material such as high-strength Al alloy on the various industries is becoming light-weight. High strength and hollow Al alloy is good material for stiffness and recycling. Therefore the advanced manufacturing technology with Al alloy is continuously required in many industrial fields. In this study simplified hallow rectangular section of Al alloy is analyzed by FE analysis. Bending stress is affected punching and rotating of wing-die. The analysis of press bending is preformed at first. The elastic recovery value of component and stress distribution acting from the result of the bending angle of three types were obtained. The designed precesses were analyzed by the commercial FE code, Deform-3D. Forming dies for each process were designed and prototypes were manufactured by the verified forming process. Some of the important features of design parameters in the press bending were reviewed.

• Journal of the Korean Society of Safety
• /
• v.33 no.4
• /
• pp.38-45
• /
• 2018

Bridges are structures where safety must be ensured. Generally, the destruction mechanism of bridge deck shows punching shear. Lately, the high-strength concrete is often used to increase the lifespan of bridges. The benefits of using the high-strength concrete are that it increases the durability and strength. On the contrary, it reduces the cross-section of the bridges. This study suggested the optimal thickness of bridge deck with application of high-strength concrete and the study evaluated its structural performance experimentally. The evaluation result shows that 180 mm and 190 mm of thickness are optimal for 100 MPa and 120 MPa high-strength concrete bridge deck respectively.

• Structural Engineering and Mechanics
• /
• v.56 no.5
• /
• pp.745-765
• /
• 2015

This paper presents the design of reinforced concrete combined footings of trapezoidal form subjected to axial load and moments in two directions to each column using a new model to consider soil real pressure acting on the contact surface of the footing; such pressure is presented in terms of an axial load, moment around the axis "X" and moment around the axis "Y" to each column. The classical model considers an axial load and moment around the axis "X" (transverse axis) applied to each column, and when the moments in two directions are taken into account, the maximum pressure throughout the contact surface of the footing is considered the same. The main part of this research is that the proposed model considers soil real pressure and the classical model takes into account the maximum pressure, and also is considered uniform. We conclude that the proposed model is more suited to the real conditions and is more economical.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.6
• /
• pp.115-122
• /
• 2012

The purpose of this study is to optimize the design of the jack-up platform for 5MW offshore wind turbine system. Considering all the environmental loads such as currents, waves, winds and so on, the members of structures have been designed and optimized based on the AISC and API-RP-2A to be within the allowable stress even in the most critical and severe condition. In addition to the above strength check of structural members, the joint punching shear check and the hydrostatic collapse check are also performed where they are required for the design. The design life of the jack-up platform is 50 years for the static strength check and the fatigue design life is 100 years including to the DFF(Design Fatigue Factor) of 2.0 to have enough stability and workability for the design optimization.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2005.05a
• /
• pp.383-388
• /
• 2005

In this paper Research development about a micro metal forming manufacturing system has been developed. A micro forming system has been achieved in Japan and it's developed micro press is limited to single forming process. To coincide with the purpose to be more practical, research and development is necessary about the press which the multi forming process is possible. We set the development of the equipment including micro deep drawing, micro punching and micro restriking process to the goal. To achieve this goal, Research about micro forming process to be related to multi process forming must be preceded first. Material selection and analysis about micro forming process are accomplished in this paper. And the basis research to make actual system is accomplished.