• 대한생식의학회:학술대회논문집
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• 1996.11a
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• pp.71-72
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• 1996

• Journal of Embryo Transfer
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• v.8 no.1
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• pp.37-44
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• 1993

Nuclear transplantation techinque has been found to be the most potential and efficient method for producing a large number of genetically identical animals from a single embryo. The technical development of nuclear transplantation in mammals and its application to the production of cloned animals were reviewed. For the efficient and successful production of cloned embryos by nuclear transplantation, selection and micromanipulation of recipient eggs or embryos as capacious recipient cytoplasm, and benefitial preparation of multiple totipotent embryonic cells as donor nuclei, and also fusion technique are very critical. Recent works approaching to these critical points were introduced and discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.675-676
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• 2007

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.275-276
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• 2003

인간과 같은 척삭동물문에 속하는 우렁쉥이 (Halocynthia roretzi)의 유생은 척추동물의 체제를 매우 단순화시킨 구조를 하고 있다 (Nishida, 1997). 유생은 약 10여종의 세포들로 구성되며, 미부 중앙에 척삭과 그 위에 신경관의 원형 (prototype)을 갖는다. 모든 배(embryo)들은 초기 발생과정에서 언제나 동일한 세포분열과 발생운명 양식을 나타낸다. 또한, 해부현미경을 이용하여 수정란으로부터 초기 원장배에 이르기까지 원하는 하나의 할구만을 분리, 제거 및 재결합하는 등의 micromanipulation실험이 가능하다. (중략)

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2462-2464
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• 2003

본 논문에서는 비젼 기반의 마이크로매니퓰레이션을 위해서 임의의 형태의 오브젝트에서 조작점을 추출하는 알고리듬을 제안한다. 본 알고리듬은 무게 중심점과 K-L 변환을 이용하여 오브젝트의 조작점을 선정하고 오브젝트와 마이크로 그리퍼가 접촉하게 되는 면에서 최외곽의 접점을 접촉점으로 선정한다.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.2
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• pp.101-105
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• 1993

This study was carried out to improve pregnancy rate in IVF-ET program through Assisted Hatching (AH) by the use of micromanipulation technique. Among 72 IVF patient, randomized 29 IVF patients were performed for AH by Partial Zona Dissection(PZD). Two to eight cell embryos were micromanipulated just before uterine transfer. The results were as follows: 1. The implantation rates of embryos between PZD group and control group were 10.0%, 4.9%, respectively. 2. The clincal pregnancy rates of both groups were 34.5%,20.9%, respectively. 3. Among 131 PZD embrys, only 2 embryos were damaged mechanically. Although there were no statistical difference in the rates of implantation and pregnancy between PZD group and control group due to small sample size, the PZD group had increasing trend in the rates of implantation and pregnancy. In conclusion, it would be thought that PZD could be adequately used to improve implantation rate and pregnancy rate in IVF-ET program as an assisted technique if much more studies were done. Also the risks resulting from this study can be reduced because of technical stability, which showed the low rate of damaged embryos.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2072-2077
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• 2003

Animal-like robots are serving an important role as a linkage between biology and engineering. So, in this paper, we aim to develop a biomimetic microrobot that mimics the locomotion mechanism of a gastropod. This microrobot has 3 DOF (x, y translation and rotation), and has small size, unlimited traveling range, high resolution and low cost. Its movement can be made using propagation wave that is generated by the controllable sinusoidal voltage source and piezoelectric effects. This soft motion that can be generated by propagation wave and piezoelectric mechanism would be useful for the motion on the slippery surface. So we modeled the propagation wave mechanism including piezoelectric effect and friction on the contact surface, and could know the velocity of the microrobot is dependent on the driving frequency, input voltage peak, propagation wavelength and surface friction coefficient. With these results we design the microrobot, and accomplish its fabrication and experimentation. The development of this microrobot shall be aimed to design an autonomous moving actuator like animal. Also it can be used from micromanipulation system technology to biology and medicine.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.146-150
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• 2004

We researched carbon nanotube(CNT) cartridge as a CNT sample for the fabrication of nanotweezer which is composed of a couple of single CNT tip. Our CNT cartridge was made by dielectrophoretic methods, a kind of micromanipulation technique using electric field. Therein we intended to fabricate the CNT cartridge with just conventional function generators and a set of simple electrode. A knife edge and a flat metal electrode were employed as a couple of electrode, and these electrode pair faced each other with the gap. When the gap is filled with CNT suspension, we induced AC electric field into the gap. Then CNTs was attached on the sharp edge in knife edge by dielectrophoresis. This knife edge with attached CNTs is called as the CNT cartridge.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.103.4-103
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• 2001

This paper presents a scaled teleoperation scheme for 3-D microassembly on the experimental microassembly workcell. A workspace mapping between a master and a slave microrobot system is presented to teleoperatively control the microrobot system for microassembly such as peg-in-hole task. Based on this result, a scaling factor is designed and applied to the teleoperated micromanipulation for peg-in-hole task in a mesoscale. Using 3-D virtual simulator, the workspace of microrobot system, and the working path trajectory for microassembly is visually represented. The proposed method is validated through the execution of 3-D microassembly such as peg-in-hole task on the experimental microassembly workcell. The proposed method in the developed ...

• Journal of Plant Biotechnology
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• v.1 no.1
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• pp.56-60
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• 1999

Sexual reproduction is an essential process in the propagation of flowering plants. Recent advances in plant cell biology and biotechnology have brought new and powerful methodologies to investigate and manipulate the reproductive processes of angiosperms including agronomically important crop plants. Successful cryopreservation of maize, rye and triticale pollen and young embryos of microspore-and zygote-origine contributes to long term preservation of important plant germ-lines in gene banks. Discovering morphogenetic characteristics of the different developmental pathways taking place in wheat and maize androgenesis in vitro helps to influence the procedure to produce genetically and phenotipically stable homozygous doubled haploid plants for breeding purposes. Detailed ultrastructural and cell-biological studies on the developmental sequences of male and female gametophyte development in wheat, experimental protocols developed to isolate and micromanipulate egg cell protoplasts, make it possible to use plant gametes and the sexual route itself to produce genetically improved organisms. Plant gametes can become useful tools for crop improvement in the near future. Recent achievements by our laboratory in this field are reviewed in the present paper