• Journal of the Korea Furniture Society
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• v.17 no.3
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• pp.29-36
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• 2006

Juvenile and matured wood of Populus tomentiglandulosa species of Salicaceae native grown in Korea was observed by FE-SEM and optical microscope. Species is characterized by mostly diffuse-porous, simple perforation plates, polygonal alternate non-vestured intervessel pit, medium length of vessel elements and fibres, non-septate very thin walled libriform fibres and exclusively uniseriate procumbent rays. Axial parenchyma was absent or extremely rare. Vessel and fibre length were longer in both matured and juvenile latewood than those of earlywood. Ray cell lumen diameter, ray length, number and diameter of endwall pit in ray cell, endwall pit, number and diameter of pit in lateral wall of one ray parenchyma cell, vessel ray pit number and diameter vary from juvenile early and latewood to matured wood.

• Speech Sciences
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• v.8 no.1
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• pp.159-165
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• 2001

In this paper, we make an experiment on speech recognition systems with barging-in and non-barging-in utterances. Barging-in capability, with which we can say voice commands while voice announcement is coming out, is one of the important elements for practical speech recognition systems. Barging-in capability can be realized by echo cancellation techniques based on the LMS (least-mean-square) algorithm. We use three kinds of telephone interface boards with barging-in capability, which are respectively made by Dialogic Company, Natural MicroSystems Company and Korea Telecom. Speech database was made using these three kinds of boards. We make a comparative recognition experiment with this speech database.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.720-721
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• 2006

The new alloy$^{1)}$ is made from rapidly solidified Al-Ni-Zr-Ce aluminum alloy powder, and has the following unique mechanical characteristics:(1) The stress-strain curve shows a yield point; (2) The alloy shows high heat resistance; (3) Although the alloy is submicron particle diameter, it shows excellent creep resistance. We observed the micro structures of this new alloy, and it is thought that is based on the following reasons:(1) The dislocation strongly adheres to the alloy's many crystal boundaries;(2) The added alloying elements have a small diffusion coefficient in aluminum;(3) The tiny intermetallic compound particles crystallizing at the grain boundary.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.9 s.90
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• pp.861-867
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• 2004

For the evaluation of acoustic noise of a DLP projector, vibration and sound characteristics of a DLP projector were studied. The acoustic noise of DLP projector could be classified into three categories, that is, the direct noise from a body of rotation, the air-bone noise generated from turbulence or vortex occurred during cooling process and the structural born noise produced by vibrating elements. Cooling fans and color filter wheel which rotates at 9000 rpm are main causes of acoustic noise induced in DLP projector. Since the structure of an optical module in a DLP projector can be excited by the excessive vibration of a color filter wheel, the structural design for anti-vibration should be considered. To make a reduction of overall acoustic noise, the anti-vibration design and the enclosing structure have been studied and applied to a color filter wheel.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.439-443
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• 1973

2-Mercaptothiazoline is very sensitive reagent for silver, which have been used for highly selective amperometric determination of silver. A method is described for the determination of micro-quantity of silver by amperometric titration with 2-mercaptothiazoline in ammonical solution. Direct titration of milligram amount of silver (0.05∼1.00mg) is possible in the presence of a number of foreign ions in ammonical solution containing ethylenediaminetetraacetic acid as masking agent under atmosphere. The interfering elements are gold and platinum. The milligram amounts of silver can be determined by the proposed method within an error ${\pm}$5%.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1071-1073
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• 2000

The use of HDL(Hardware Description Language) is now central to the ASIC(Application Specific Integrated Circuit). HDL-based ASIC can simplify the process of development and has a competition in market because it reduce the consuming time for the design of IC(Integrated circuit) in system level. Therefore, the development of power electronics system on chip (SOC), to design microcontroller and switching logic as one chip, is required extremely for the purpose of having reliability and low cost in power electronics which is based on switching elements. The major application of SOC is variable converter, active filter inverter for induction motor. UPS and power supply with a view to reducing electro-magnetic pollution.

• BMB Reports
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• v.49 no.1
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• pp.18-25
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• 2016

Recent evidence has indicated that nano-sized vesicles called "exosomes" mediate the interaction between cancer cells and their microenvironment and play a critical role in the development of cancers. Exosomes contain cargo consisting of proteins, lipids, mRNAs, and microRNAs that can be delivered to different types of cells in nascent as well as distant locations. Cancer cell-derived exosomes (CCEs) have been identified in body fluids such as urine, plasma, and saliva from patients with cancer. Although their content depends on tumor type and stage, CCEs merit consideration as prognostic and diagnostic markers, as vehicles for drug delivery, and as potential therapeutic targets because they could transport various oncogenic elements. In this review, we summarize recent advances regarding the role of CCEs in cancer invasion and metastasis, as well as its potential clinical applications. [BMB Reports 2016; 49(1): 18-25]

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.46-52
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• 1985

A theoretical study of mutual coupling effects between two H-plane coupled microstrip patch antennas is presented. The radiation resistance and slot capacitance of a single micro-strip patch are calculated. To investigate the mutual coupling effects, the even and odd mode characteristic impedance and effective dielectric constants are obtained using the coupled microstrip line model. The S-parameter matrix elements 511,512 are used to study the mutual coupling e(facts in S-band frequency ranges for various patch spacings. Theoretical results and measurements are in good agreement.

• Steel and Composite Structures
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• v.4 no.2
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• pp.113-132
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• 2004

Double skin composite element (DSCE) is a novel form of construction comprising two skins of profiled steel sheeting with an infill of concrete. DSCEs are thought to be applicable as shear or core walls in a building where they can resist in-plane loads. In this paper, the behaviour of DSCE subjected to combined bending and shear deformation is described. Small-scale model tests on DSCEs manufactured from micro-concrete and very thin sheeting were conducted to investigate the flexural and shear behaviour along with analytical analysis. The model tests provided information on the strength, stiffness, strain conditions and failure modes of DSCEs. Detailed development of analytical models for strength and stiffness and their performance validation by model tests are presented.

• Structural Engineering and Mechanics
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• v.17 no.1
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• pp.69-85
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• 2004

The novel form of composite walling system consists of two skins of profiled steel sheeting with an in-fill of concrete. Such walling system can be used as shear elements in steel framed building subjected to lateral load. This paper presents the results of small-scale model tests on composite wall and its components manufactured from very thin sheeting and micro-concrete tested under monotonic and cyclic shear loading conditions. The heavily instrumented small-scale tests provided information on the load-deformation response, strength, stiffness, strain condition, sheet-concrete interaction and failure modes. Analytical models for shear strength and stiffness are derived with some modification factor to take into account the effect of quasi-static cycling loading. The performance of design equations is validated through experimental results.