• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.41-45
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• 2018

We have simulated the process induced warpage for panel level package using finite element method. Silicon chips of $5{\times}5mm^2$ were redistributed on $122.4{\times}93.6mm^2$ size panel and the total number of redistributed chips was 221. The warpage at each process step, for example, (1) EMC molding, (2) attachment of detach core, (3) heating, (4) removal of a carrier, and (5) cooling was simulated using ANSYS and the effects of detach core and carrier materials on the warpage were investigated. The warpage behaved complexly depending on the materials for the detach core and carrier. However, glass carrier showed the lower warpage than FR4 carrier regardless of detach core material, and the minimum warpage was observed when the glass was used for the detach core and carrier at the same time.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.756-759
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• 2007

We have fabricated pentacene OTFT on ultra-thin flexible polyimide film with a rigid glass support. Polyimide film of the thickness of $10{\mu}m$ has formed on glass by spin coating from the solution. After the entire OTFT process, the OTFT exhibited a fieldeffect mobility of $0.4\;cm^2/Vs$, an $I_{on}/I_{off}$ ratio of $10^7$ and a subthreshold swing of 0.7 V/dec. The OTFT on polyimide film has been detached from the glass support and laminated on a plastic support of $130\;{\mu}m-thick$ PET film. After the detach process, in spite of the degrading of its field-effect mobility, the OTFT showed high $I_{on}/I_{off}$ as high $as{\sim}10^6$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.40-44
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• 2000

A microscopic study was carried out to get the fundamental informations for the ozone deinking technology. The differential interference microscopic observation showed that ozone treatment was helpful to detach the toner ink from the surface of pulp fiber. The modifications of fiber surfaces by ozone treatment were observed with scanning electron microscope. Modification of fiber surfaces was not severe at the early stage of ozone treatment, but it increased with ozone treatment time and pulp consistency, Therefore, it would be possible to improve the properties of deinked pulp by controlling the condtion of ozone treatment.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.414-417
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• 2008

A lid & frame used as the shield of electromagnetic waves in cellular phones are composed of frame, which is welded at their electric circuits, and lid, of which debonding and joining are available from the frame. Typical lid & frame were mechanically bonded by contact between the embossing of lid and the piercing of frame Bonding force of this part have to allow us to detach the lid from frame for exchange or fix of the electric part and have to be high enough to protect the electric part from external impacts. This study is designed to estimate the effect of design variable of lid & frame on its debonding force. Estimations were performed by finite element method.

• Tribology and Lubricants
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• v.21 no.5
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• pp.236-240
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• 2005

In order to prepare for the suitable surfaces of implants or medical devices, quantitative evaluation of adhesion between cells and biomaterials is essential. To better understand adhesion formation between cells and biomaterials, we used the cytodetachment technique which measures the adhesive force of a single cell through changing the, culture time and detachment speed. The results showed that the adhesive force could be affected by the culture time of cells on the surface of materials and the detachment speed. Moreover, there was a large discrepancy among the adhesion strength measured by similar techniques conducted on the different cells and substrates. It can be 'concluded that the variation of the force measurement technique can seriously alter the level of the force required to detach a cell on the surface of materials.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.1
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• pp.90-101
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• 1998

This paper presents a scheduling method that uses Petri net modeling and heuristic search to handle the tool setup. In manufacturing systems, a tool is attached to a particular machine to process a particular operation. The activity to attach a tool to a particular machine and detach the tool from the machine requires time. The processing time of operations varies according to the attached tool and the machine used. The method proposed in this paper uses Petri net to model these characteristics and applies a search algorithm to the reachability graph of the Petri net model to generate an optimal or near-optimal schedule. New heuristic functions are developed for efficient search. The experimental results that show the effectiveness of the proposed method are presented.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1519_1520
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• 2009

This paper investigates forces on a charged particle used in the e-paper application. The particles were inserted into the pixels and according to the applied voltage, particles moves up or down to the electrodes. So, to design the e-paper, the force analysis is very important for the stable operation of e-paper. For these purposes, we divided forces into 4 different forces and numerically evaluated each force. From the simulation results, we confirmed that the minimum voltage to detach the particle from the bottom electrode can be obtained for the given condition.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.362-366
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• 2004

Quantitative evaluation of substrates for cells is essential to understanding cell-material adhesive interaction and it is also necessary for the development of new biomaterials. Many cells on adhesive molecules will form an organization of actin into bundles and production of the large, highly organized structures termed focal adhesions. To better understand adhesion formations between cells and substrata, we have quantified the force required to displace attached cell. we allowed rabbit knee chondrocyte to attach on a substratum of microscope slide glass. Our results demonstrate that a force is required to detach cells is changed according to detachment time variation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.307-315
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• 1993

A direct draft measurement system was developed based on the swingle tree- the rear component of the single-animal harnessing (or yoking) system . The prototype was made from a tube, on which four strain gages were attached. The pull of the draft animal through the flexible pull chains or ropes causes the beam to bend, The bending strain is sensed by the strain gages and the bridge converts this to a voltage signal. Counterweights keep the tube correctly oriented if the angle of pull changes , while end bearing follow the variations in the angle of pull. Hence, the voltage output is proportional to the draft. the device has highly linear response, acceptable sensitivity negligible error and hysteresis. It is suitable for electronic data acquisition, non-intrusive , easy to attach and detach and is reasonably priced.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.456-460
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• 2009

Biofilm is a structured community of microorganism encapsulated within a self-developed polymeric matrix and adherent to a living or a solid surface. In this study, we investigated the effects of various substrates on the formation of biofilm in Vibrio parahaemolyticus. We found that biofilm formation profoundly increased in a substrate, that consisted of calcium chloride, calcium nitrate, and calcium sulfate in 1% peptone water. On the other hand, a dramatic reduction in biofilm formation was observed in a substrate, that consisted of glucose and ferric chloride in LB broth. These results suggest that V. parahaemolyticus prefer to form a biofilm on the surface of a crustacean or a clam, where calcium ion is rich, and also where seawater temperature is relatively lower. In contrast, high levels of glucose in a crustacean or a clam body resulting from increased seawater temperature, can make V. parahaemolyticus detach from it and lead to free floating.