https://pubs.kist.re.kr/handle/123456789/75383 Sun, 05 Apr 2026 03:41:33 GMT 2026-04-05T03:41:33Z https://pubs.kist.re.kr/handle/201004/117074 Title: FDTD validation on an improved virtual transmission-line conversion model of open-ended coaxial probe Authors: Jo, YS; Kim, SY Thu, 01 Jan 2004 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/117074 2004-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/117075 Title: Effect of cell growth phase on hydrogen production by Chlamydomonas reinhardtti Authors: Pak, D; Kim, J Abstract: Effect of cell growth phase on hydrogen production was investigated with Chlamydomonas reinhardtti. Cells were continuously cultured in photobioreactor and taken at different growth phase to produce hydrogen. Hydrogen production by cells of different growth phase was compared under dark fermentation and sulfur deprivation. Hydrogen production by cells of mid or late exponential phase was higher than cells of early exponential phase or stationary phase in dark fermentation. Under sulfur deprivation, cell growth phase did not affect hydrogen production rate. Thu, 01 Apr 2004 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/117075 2004-04-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/117073 Title: Droplet-based magnetically activated cell separation Authors: Kim, YH; Hong, S; Kim, B; Yun, S; Kang, YR; Paek, KK; Lee, JW; Lee, SH; Ju, BK Abstract: In this study, we developed a method that target cells in suspension can be separated by combining magnetic force and gravitation force. Since the newly developed method involves a separating process of a droplet containing non-target cells in suspension by applying magnetic force to separate target cells, we called it droplet-based magnetic activated cell sorting (dMACS). To demonstrate the efficiency of the dMACS system, Ter119 (+) cells from mouse bone marrow cells were separated by both conventional MACS and our dMACS systems. Effects of three parameters on separation efficiency were examined in the dMACS system. As a result, both volume of droplet of cell suspension, and magnetic force did not affect the efficiency of cell separation markedly. However, the time for cell settlement in the droplet showed a critical role in the efficiency of cell separation according to increasing time. Therefore, we tried to verify that the saturation time affected increase of its efficiency and that flow rate injected to get rid of the negative cell resulted in the decrease of its efficiency. Using this dMACS system, we were able to pinpoint that the flow rate of cell suspension injected into a magnetic platform results in disturbance in the droplet, leading to turbulence in the cell suspension. Thu, 01 Jan 2004 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/117073 2004-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/117072 Title: Energy-based control of a passive haptic device Authors: Cho, C; Song, JB; Kim, M; Hwang, CS Abstract: In this paper, we propose an energy-based control method of a passive haptic device equipped with electric brakes. Unstable behavior is observed in the passive haptic system due to time delay mainly arising from the slow update rate of the virtual environment. From the passive FME (Force Manipulability Ellipsoid) analysis, a so-called direct force control method is proposed in this paper. Its gain is computed by force analysis at the end-effector of a passive haptic device so that the component of a resultant force at the end-effector causing a pullback motion becomes zero. However, this direct force control scheme requires precise measurement of the hand force input by a human operator. We also propose the indirect force control scheme in which the gain in the direct force control scheme is computed using the notion of passivity without resorting to the high precision force sensor. For the experiments a 2-link passive haptic system was developed in this research. Various experiments have been conducted to investigate the validity of both direct and indirect force control schemes proposed in this paper. It is shown that both schemes produce satisfactory performance in the force display for the wall-following task on the virtual wall. Thu, 01 Jan 2004 00:00:00 GMT https://pubs.kist.re.kr/handle/201004/117072 2004-01-01T00:00:00Z