• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.247-247
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• 2000

A new bioelectric impedance measurement method is proposed for the precise measurement of the bioelectric impedance. To obtain the impedance from the known applied a.c. current and the measured voltage signals, a frequency conversion circuit, like the mixer in heterodyne receivers, is introduced to reduce the frequency of the original current. It can be observed from several lines of derivation that the impedance is independent on the amplitude and phase of the mixing signals. This makes it possible to use low-speed analog-to-digital converters and thus utilize cheaper electronic parts in the implementation. The possibility of the method is shown by simulations, and a generic structure applicable to bioelectric impedance measurement devices is also proposed.

• Journal of Sensor Science and Technology
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• v.24 no.1
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• pp.35-40
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• 2015

Electrospinning method has easy preparation of nanofibers with a simple and versatile technique. Electrospun nanofiber is widely used by the simple approach and have great potentials in the numerous applicaitons of medicine, photonics, catalysts, sensors, etc. including advantage of their specific characteristics such as large surface to volume ratio. This paper focused on the fabrication of cobalt electrospun nanofibrer for applications such as electronic, optical and mechanical devices by metal based material. We fabricated cobalt nanofibers on aluminum foil by an electrospinning method. The electrospinning process was performed at a high voltage, 8 kV. The distance between the needle tip and the solution surface in the bath was 5 cm. The PVB - cobalt based nitrate solution was filled in a 10 mL syringe connected to a 22 gauge needle. We confirmed electrospun cobalt nanofiber after annealing process by SIMS (Secondary Ion Mass Spectrometry) analysis. The concept design, fabrication and results of mapping measurements are reported.

• Journal of Sensor Science and Technology
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• v.16 no.4
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• pp.313-318
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• 2007

Single-wall carbon nanotube field-effect transistors (SWCNT FETs) of top gate structure were fabricated in a conventional metal-oxide-semiconductor field effect transistor (MOSFET) with gate electrodes above the conduction channel separated from the channel by a thin $SiO_{2}$ layer. The carbon nanotubes (CNTs) directly grown using thin Fe film as catalyst by thermal chemical vapor deposition (CVD). These top gate devices exhibit good electrical characteristics, including steep subthreshold slope and high conductance at low gate voltages. Our experiments show that CNTFETs may be competitive with Si MOSFET for future nanoelectronic applications.

• Journal of Technology Innovation
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• v.8 no.2
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• pp.119-143
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• 2000

The main objective of this study is to test hypotheses by empirical study on the technology transfer from a national institute to small and medium sized enterprises(SMEs) in the Korean electronic devices industry. The important findings of the study are as follows: First, the success of the technology transfer from national institute to SMEs depends on the character of the project manager such as research experience and academic degree level. Second, the success of the technology transfer is related to the nature of the research project, especially to the technology life cycle stage but insignificantly to the amount of R&D fund and duration. Third, another success factor for technology transfer is the joint technology development between institute and SMEs, which is due to the possibility of early commercialization of the technology development project. Fourth, the hypothesis about the relationship between the project selection and evaluation results and technology transfer success is not statistically supported.

• Fashion & Textile Research Journal
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• v.9 no.5
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• pp.493-499
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• 2007

The purpose of this study was to investigate the components of newness and product innovativeness of smart clothing, and to examine the evaluation of newness and innovativeness of smart clothing according to the consumer innovativeness. The survey was conducted on male and female subjects aged from 17 to 50. A total of 338 valid responses were used for the analysis. Exploratory factor analysis and confirmatory factor analysis confirmed the evaluation of smart clothing newness consisted of five items: 'novel', 'modern', 'original', 'fresh' and 'up-to-date'. The evaluation of smart clothing innovativeness consisted of two dimensions. One is the evaluation of innovativeness as clothing and the other is the evaluation of innovativenss as electronic devices. The validity of two dimensions were verified by confirmatory factor analysis. The results of ANOVA and Duncan test indicated that there were differences in the evaluation of newness and smart clothing innovativenss according to consumer innovativeness.

• Progress in Superconductivity
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• v.4 no.1
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• pp.14-18
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• 2002

We had succeeded to grow bulk sing1e crystals of La／sub 2-x／Sr／sub x／$CuO_4$by the traveling solvent floating zone method (TSFZ), and to prepare La／sub 2-x／Sr／sub x／CuO$_4$single-crystalline thick films on the Zn-doped La$_2$$CuO_4$ substrate by new liquid phase epitaxial technique using an infrared heating furnace (IR-LPE). In this paper, Ireview growth of bulk single crystals and single-crystalline thick films of La／sub 2-x／Sr／sub x／$CuO_4$, and discuss on their device properties to develop high speed integrated electronic devices.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.72-74
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• 2014

Multilayer ceramic capacitor (MLCC) makes acoustic noise of electronic devices. Conversed piezoelectric effect of dielectric substance consists of $BaTiO_3$ causes vibration of MLCC so it must be analyzed to reduce the noise. Thus, finite element model for piezoelectric analysis of MLCC was constructed in this paper. Piezoelectric characteristics of MLCC was considered for the accurate simulation result. Displacement response for sinusoidal voltage signal was measured and simulation result was verified with test result.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.507-510
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• 2002

We developed a human-sized BWR(biped walking robot) named KUBIRI driven by a new actuator based on the ball screw which has high strength and high gear ratio. KUBIRI was developed to walk autonomously such that it is actuated by small torque motors and is boarded with DC battery and controllers. To utilize informations on the human walking motion and to analyze the walking mode of robot, a motion capture system was developed. The system is composed of the mechanical and electronic devices to obtain the joint angle data. By using the obtained data, a 3-D graphic interfacer was developed based on the open inventor tool. Through the graphic interfacer, the control input of KUBIRI is performed.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.7-7
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• 2011

Graphene and graphene derivatives have attracted enormous attention from various research fields for applications in electronic devices, transparent electrodes, biosensors, drug delivery system and surface coatings. In the viewpoint of chemist, the chemical structure of graphene derivatives seems intriguing but detailed structures are being revealed only recently while engineering approaches for various applications are being executed very actively. In addition, cytotoxicity and mammalian cellular responses to graphene have not thoroughly investigated yet in spite of the importance in bio-applications and environment. In this talk, I'll introduce recent studies which report cytotoxicity and behaviors of mammalian cells when the cells are exposed to graphene (as well as some bio-applications of graphene), especially to get closer to answers to these questions, "how we understand and how/why we use graphene in biotechnology".

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.300-300
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• 2011

Si oxidation is a key process in developing silicon devices, such as highly integrated metal-oxide-semiconductor (MOS) transistors and antireflection-coating (ARC) on solar cell substrate. Many experimental and theoritical studies have been carried out for elucidating oxidation processes and adsorption structure using ab initio total energy and electronic structure calcultaions. However, the initial oxidation processes at step edge on vicinal Si surface have not been studied using the ReaxFF reactive force field. In this work, strucutural change, charge distribution of oxidized Si throughout the depth from Si surface were observed during oxidation processes on vicinal Si(001) surface inclined by $10.5^{\circ}$ of miscut angle toward [100]. Adsorption energys of step edge and flat terrace were calculated to compare the oxidation reaction at step edge and flat terrace on Si surface.