• Transactions of Materials Processing
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• v.14 no.5 s.77
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• pp.473-476
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• 2005

The demand of on-chip total analyzing system with MEMS (micro electro mechanical system) bio/chemical sensor is rapidly increasing. In on-chip total analyzing system, to detect the bio/chemical products with submicron feature size, a filtration system with nano-filter is required. One of the conventional methods to fabricate nano-filter is to use direct patterning or RIE (reactive ion etching). However, those procedures are very costly and are not suitable fur mass production. In this study, we suggested new fabrication method for a nano-filter based on replication process, which is simple and low cost process. After the Si master was fabricated by laser interference lithography and reactive ion etching process, the polymeric mold was replicated by UV-imprint process. Metallic nano-filter was fabricated after removing the polymeric part of metal deposited polymeric mold. Finally, our fabrication method was applied to metallic nano-filter with $1{\mu}m$ pitch size and $0.4{\mu}m$ hole size for bacteria sensor application.

• Phonetics and Speech Sciences
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• v.2 no.3
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• pp.81-89
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• 2010

Korean and three other languages (English, Arabic, and Japanese) were compared with regard to the compensatory movements in a VC (Vowel and Consonant) sequence and word. For this, Korean data were collected from an experiment and the other languages' data from literature. All the test words of the languages had the same syllabic contexture, i.e., /CVCV(r)/, where C was an oral stop and intervocalic consonants were either bilabial or alveolar stops. The present study found that (1) Korean is most striking in the durational variations of segments (vowel and the following hetero-syllabic consonant); (2) unlike the three languages that show a constant sum of VC, Korean yields a three-way distinction in the length of VC according the type (lax unaspirated vs. tense unaspirated vs. tense aspirated) of the following stop consonant; (3) a durational constancy is maintained up to the word level in the three languages, but Korean word duration varies as a function of the feature tenseness of the intervocalic consonants; (4) consonant duration is proven to differentiate Korean the most from the other languages. It is suggested that the durational difference between a lax consonant and its tense cognate(s) and the degree of compensation between V and C are determined by the phonology in each language.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.12 s.177
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• pp.184-189
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• 2005

An experimental study of the femtosecond laser machining of Si materials was carried out. Direct laser machining of the materials for the feature size of a few micron scale has the advantage of low cost and simple process comparing to the semiconductor process, E-beam lithography, ECM and other machining process. Further, the femtosecond laser is the better tool to machine the micro parts due to its characteristics of minimizing the heat affected zone(HAZ). As a result of line cutting of Si, the optimal condition had the region of the effective energy of 2mJ/mm-2.5mJ/mm with the power of 0.5mW-1.5mW. The polarization effects of the incident beam existed in the machining qualities, therefore the sample motion should be perpendicular to the projection of the electric vector. We also observed the periodic ripple patterns which come out in condition of the pulse overlap with the threshold energy. Finally, we could machined the groove with the linewidth of below $2{\mu}m$ for the application of MEMS device repairing, scribing and arbitrary patterning.

• Journal of KIISE:Information Networking
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• v.35 no.3
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• pp.207-214
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• 2008

There are lots of studies on application systems using wireless sensor networks. As the application systems are adapted to industrial field, the reliability of these systems becomes new key feature. The lack of reliability is an obstacle to extension of wireless sensor networks. In this paper, we propose the monitoring system framework that can offer the reliability of wireless sensor networks using a micro camera module and wireless sensor network nodes. And also we propose the efficient transfer method for image information over low rate wireless networks. Using these system framework and transfer method, we implement WiSN(Wireless image Sensor Network) based fire monitoring system.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.172-175
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• 1999

Relative DNA contents in some harmful algae were measured using DAPI staining and image analysis system. This method was useful to identify some morphologically similar species and isolates from harmful algal blooms (HABs). In exponential phase, Prorocentrum micans had higher relative DNA content (RD) of $1.83\pm0.52$ than any other isolates, followed by Cochlodinium polykrikoides $(1.10\pm0.46)$ Alexandrium tamarense $(0.93\pm0.32)$ Gyrodinium impudicum $(0.56\pm0.17)$, Scrippsiella trochoidea $(0.41\pm0.26)$ and P. minimum$(0.05\pm0.01)$. When they were fixed with Lugol's solution, it was difficult to d,iscern C. polykrikoides from G. impudicum under the light microscope, but the DNA contents were quite different in two species. C. polykrikoides contained about twice as much RD as G. impudicum under the same culture conditions and exponential phase. DAPI­stained DNA feature in C. polykrikodes showed concentrated in the peripheral part of the cell, but in G. impudicum showed a compact structure in the central part. Although A. tamarense and S. trochoidea were morphologically similar under the light microscope, nuclear DNA content of A. tamarense was twice as much as that of S. trochoidea.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.856-860
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• 2007

In this paper, we propose a microstrip antenna with sufficient impedance bandwidths and gains for the 2.65GHz antenna which used in the satellite digital multimedia broadcasting. The proposed 2.65GHz S-DMB bandwidth microstrip antenna on a substrate, which is small enough to be installed in practical mobile phones, and described simulation feature using by CST Microwave Studio program. The measured result is similar with commercial antenna and acceptable frequency band is found that more wide than the existing products.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.4
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• pp.406-412
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• 2009

ECG is used on purpose to keep good health or monitor cardiac function of aged person as well as on purpose to diagnose the disease of heart patients. The ambulatory ECG monitoring system under guarantee of safety and accuracy is very efficient to prevent the progress of heart disease and sudden death. These systems can detect the temporary change of ECG that is very significant to diagnose heart disease such as myocardial ischemia, arrhyamia and cardiac infarction. In this paper, we describe the ECG signal analysis algorithm and measurement device for ECG monitoring. The authors designed a small-size portable ECG device that consisted of instrumentation amplifier, micro-controller, filter and RF module. The device measures ECG with four electrodes on the body and detects QRS complex and ST level change in realtime. Also it transmits the measured signals to the personal computer. The developed software for ECG analysis in personal computer has the function to detect the feature points and ST level changes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12C
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• pp.1157-1164
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• 2006

In this paper, we proposed a method for measuring accurate positions and sizes of package and balls in a micro BGA. To find defects of BGA accurately, we focused on finding positions of package and balls. After labeling, we detected connected components of package and balls using feature parameters. After the detection of package component, we measured position and size of package by employing rectangular model which was constructed by the package information. After the detection of the ball components, we measured positions and diameters of balls by employing circular models which were constructed by the ball informations. We did calibration based on landmarks to measure real length, and we compared the measured results with the SEM data. Finally, we found that the accuracy of the proposed method is 94% in terms of ball's radius.

• Convergence Security Journal
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• v.14 no.7
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• pp.9-15
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• 2014

In this paper, we proposed a new LDP code to solve a previous LDP code's problem and can include a face-color information. To include the face-color information, we developed various methods reducing the existing LDP code and analyzed the results. A new LDP code is represented by 6-bits different from the previous LDP code To adapt to a noise and environmental changes effectively and include 2-bits face-color information. The result shows better recognition rates of face and facial-expression than the existing methods effectively.

• Journal of IKEEE
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• v.19 no.1
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• pp.52-57
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• 2015

The disease diagnosis system has been developed using the thin nitride(Si3N4) cantilever arrays which can measure the difference of capacitances between sensor and reference. The system consists of 32-bits RISC(Reduced Instruction Set Computer), RAM/Flash, bus, communication IP's, ADC(Analog Digital Converter) board, and LCD display. The marker selection method, which give us the good accuracy from reasonal numbers of markers, is suggested. The developed system has the resolution under 1fF and can detect 10nM concentration of Thrombin.