• International journal of advanced smart convergence
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• 제2권2호
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• pp.16-18
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• 2013

In this paper, we develop a method to design a flexible thin film audio systems utilizing Polyvinylidene fluoride. The system we designed showed the properties of increased transparency and sound pressure levels. As an input terminal transparent oxide thin film is adopted. In order to provide dielectric insulation, a transparent insulating oxide thin film is coated to obtain double -layered structure. In the range of visible light, the output from the output of the system showed an increased and improved sound pressure level. The piezoelectric polymer film of polyvinylidene fluoride (PVDF) is used to produce mechanical vibration due to the applied electrical voltage signal. An analog electric voltage signal is transformed into sound waves in the audio system.

• International journal of advanced smart convergence
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• 제2권2호
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• pp.23-26
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• 2013

Social networking services that connect a person to other people are attracting people's attention and various types of services are provided on the Internet. Library has been playing a role of social media by providing us with materials such as books and magazines, and with a place for reading, studying, getting lectures, etc. In this paper, we present a method for finding candidates of groups of the library's patrons who share interest areas by utilizing the loan records, which are obtainable in every library. Such a homogeneous group can become a candidate for a study group, a community for exchange ideas, and other activity group. We apply the method to a collection of loan records of a university library, find some problems to be solved, and propose measures for more detailed solutions. Even though the potential group finding problem still remains a lot of issues to be solved, its potential importance is very high and thus to be studies even more for future applications.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1225-1228
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• 2004

Principles and mechanism of energy transduction of dielectric polymer materials are well known from the various smart material related publications. However their introduction to industrial actuator applications is limited mainly due to difficulties guarantee controllability and reliability. Most of the previous publications have elaborates energy transduction physics of chunk of polymer while development of construction methods for feasible actuators made of the material is rarely proposed. In the present article, a conceptual design of multi-DOF linear polymer actuator construction that is to be controllable with moderate level of control work os introduced. In addition, numerical models that are developed with a unified energy based approach are presented not only for basic working mechanism analysis of the polymetric soft actuator but for providing analytical foundation to expend the concept toward design of multi-DOF actuator controls.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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• pp.416-421
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• 2005

Concrete are brittle materials and they are which come to brittle fracture rapidly by progress of cracks. Therefore, what the time for repairing the damage portion is understands importantly by such cracks. When they happened the glass pipe similar to concrete was used. Such a glass pipe can insert repair material in an inside, or can use it by switch. They are interested in the crack monitoring of structure using FM radio sensor and PZT sensor. In this study, the monitoring to a crack was studied using FM radio sensor and PZT sensor. Therefore, the purpose of this study is the fundamental research which detects damages of main members using the compound sensor which consisted of the radio sensors of resistance, PZT, and FM system.

• Smart Structures and Systems
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• 제21권6호
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• pp.777-791
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• 2018

This paper discusses the shape control of deformable mirrors for Adaptive Optics in the dynamic range. The phenomenon of control-structure interaction appears when the mirror becomes large, lowering the natural frequencies $f_i$, and the control bandwidth $f_c$ increases to improve the performance, so that the condition $f_c{\ll}f_i$ is no longer satisfied. In this case, the control system tends to amplify the response of the flexible modes and the system may become unstable. The main parameters controlling the phenomenon are the frequency ratio $f_c/f_i$ and the structural damping ${\zeta}$. Robustness tests are developed which allow to evaluate a lower bound of the stability margin. Various passive and active strategies for damping augmentation are proposed and tested in simulation.

• Smart Structures and Systems
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• 제16권4호
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• pp.667-681
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• 2015

The scour induced by strong currents and wave action decreases the embedded length of monopiles and leads to a decrease of their structural stability. The objective of this study is the development and consideration of scour-monitoring techniques for offshore monopile foundations. Tests on physical models are carried out with a model monopile and geo-materials prepared in a cylindrical tank. A strain gauge, two coupled ultrasonic transducers, and ten electrodes are used for monitoring the scour. The natural frequency, ultrasonic reflection images, and electrical resistivity profiles are obtained at various scour depths. The experimental results show that the natural frequency of the model monopile decreases with an increase in the scour depth and that the ultrasonic reflection images clearly detect the scour shape and scour depth. In addition, the electrical resistivity decreases with an increase in scour depth. This study suggests that natural frequency measurement, ultrasonic reflection imaging, and electrical resistivity profiling may be used as effective tools to monitor the scour around an offshore monopile foundation.

• 대한화학회지
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• 제46권3호
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• pp.225-228
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• 2002

폴리아닐린에 전자주게기(-CH3)를 치환하여 전자효과(electronic effect) 와 입체장애효과(steric effect)를 확인하기 위하여 폴리아닐린 유도체인 폴리톨루이딘(POT)1을 화학적 및 전기화학적으로 합성한 결과 입체장애효과가 더 우세하였다. 순환전압 전류법(Cyclic Voltammetry)과 전위차벗김 분석법(Constant Current Potentiometric Stripping Analysis)을 사용한 결과 POT의 IP는 4.95eV, EA는 3,24eV, Eg는 1.71eV임을 확인하였다.

• 대한화학회지
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• 제46권3호
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• pp.229-232
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• 2002

폴리아닐린에 전자주게기(-CH3)를 치환하여 전자효과(electronic effect) 와 입체장애효과(steric effect)를 확인하였다.1 폴리아닐린 유도체 폴리톨루이딘(POT)의 산화상태를 변화시키면서 ITO/POT/Al 구조의 유기발광소자를 제작하여 PL, I- V 특성 및 전기발광 특성을 확인하였다. 발광소자의 구동전압은 9∼14 V 이었다.

• 분석과학
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• 제27권3호
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• pp.121-139
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• 2014

In this review, we will discuss aptamer technologies including in vitro selection, signal transduction mechanisms, and designing aptamers and aptazyme for label-free biosensors and catalysts. Dye-displacement, a typical label-less method, is described here which allows avoiding relatively complex labeling steps and extending this application to any aptamers without specific conformational changes, in a more simple, sensitive and cost effective way. We will also describe most recent and advanced technologies of signaling aptamer and aptazyme for the various analytical and clinical applications. Quantum dot biosensor (QDB) is explained in detail covering designing and adaptations for multiplexed protein detection. Application to aptamer array utilizing self-assembled signaling aptamer DNA tile and the novel methods that can directly select smart aptamer or aptazyme experimentally and computationally will also be finally discussed, respectively.

• 한국수정란이식학회지
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• 제14권1호
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• pp.47-57
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• 1999

Among proteins separated from methanol extract of follicular fluid with superose column, the components inducing sperm swim-up separation through sucrose layer were analysed with superose column in Smart system and SDS-PAGE. And the results obtained were as follows; The fractions of retention volume (RV) 0.83ml and RV 1.36ml separated with superose column should stimulate sperm migration and movement. However, RV 0.83 fraction was consisted of complex materials containing RV 1.36 component. RV 1.36 fraction contained a BSA analogue of 67 kilodaltons (Kd) and showed identical peak pattern with BSA fraction V. In conclusion, the protein of 67 Kd in follicular fluid should stimulate sperm migration and movement.