• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.185-190
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• 1993

The POSTECH Hand adopting coupled tendon driven technique with planar two fingers is developed. The hand is designed to emulate principal motions of the human hand which has two and three joints respectively. Its kinematic parameters are determined through a parameter optimizing technique to aim at improving the isotropy of fingertip motions with new criterion functions of design. For the control of the hand, tension and torque control algorithms are developed. Based on the virtual stiffness concept, we develop the stiffness control method of a grasped object with redundant finger mechnism and investigate experimentally.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.178-182
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• 1992

For an industrial-scale purification and production of cephalosporin C from a culture broth of Ceplzalos#mium nmemonium CSA-2.8A3 mutant, ultrafiltration, column chromatography, reverse osmosis, and spray drying were empolyed. Above 90% of yield and high purity of cephalosporin C were obtained through WA-30, HP-20, XAD-2000 and SK-1B column chromatographies. Especially, in the tendom operation of the columns, the recovery yield was increased up to 96%. The purified cephalosporin C was stable at $4^{\circ}C$ and in acidic condition, while it was unstable at room temperature and in alkaline condition at pH above 8.0. Cephalosporin C powder or a final product prepared by spray drying contained 85.554 of sodium cephalosporin C, 6.3%' of water, 4.63% of free $Na^+$ ions. and traces of metal ions.

• Journal of Urban Science
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• v.11 no.2
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• pp.19-24
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• 2022

Conventional RC beams for crossing small and medium-sized rivers do not have a cross-sectional area, so the floating debris is accumulated and disasters such as damage to bridges occur. To improve this, the PSC method was invented. However, this also had problems such as transverse curvature, increase in dead weight due to cross-sectional shape, and negative moment generated during serialization, so it was necessary to develop a new type of girder. Therefore, it was intended to propose a LIT(Leton Interaction Thrust) girder bridge that is safer and has better performance than the conventional PSC girder with improved section efficiency. Unlike existing girder bridges, the LIT girder has the feature that the change in the strands of the entire girder occurs only in the vertical direction when the first tension is applied because the tendon arrangement is symmetrical by applying the raised portion. In addition, slab continuation generates a secondary moment that is advantageous to the continuous point, effectively controlling the negative moment and preventing the corrosion of the tendon. The dimensions of the cross section were determined, and the arrangement of the strands was designed to conduct structural analysis and detailed analysis. As a result of the structural analysis, the stress of the girder showed results within the allowable compressive stress, and the deflection showed the result within the allowable deflection. showed results. In addition, a detailed analysis was performed to examine the stress distribution around the girder body and the anchorage area and the stress distribution of the embossed portion, and as a result, the stress of the girder body due to the tension force showed a stable level.