• ETRI Journal
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• v.29 no.2
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• pp.162-168
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• 2007

A new scheme for bi-directional HDTV/Gigabit Ethernet/CATV transmission over a hybrid dense-wavelength-division-multiplexing passive optical network (DWDM-PON) is proposed and demonstrated. It is based on injection-locked vertical-cavity surface-emitting lasers and distributed-feedback laser diodes as transmitters. Services with 129 HDTV channels, a 1.25 Gbps Gigabit Ethernet connection, and 77 CATV channels are successfully demonstrated over 40 km single-mode fiber links. Good performance of bit error rate, carrier-to-noise ratio, composite second order, and composite triple beat is achieved in our proposed bidirectional DWDM-PON.

• Journal of ILASS-Korea
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• v.28 no.4
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• pp.169-175
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• 2023

Multi-injection scheme is being applied to GDI combustion to reduce PM and PN emission to meet the EU7 regulation. However, very short injection duration encounters the ballistic injection region, which injection quantity does not increase linearly with injection duration when applying multi-injection. In this study, numerical studies were conducted to reveal the cause of ballistic injection and the effect of design parameters on ballistic region using 1-D simulation, AMESim. Injection rate and injection quantity were compared with experiment to validate the established model, which showed the accuracy with 10% error. The model revealed that the tendency of ballistic region coincides with the needle motion behavior, which means that parameters at the upper part of needle such as electro-magnetic force, needle spring force and needle friction force have dominant effect on ballistic injection. To figure out the effect of electro-magnetic and needle friction force on ballistic, those parameters were varied to plus and minus 10% with model. The result showed that those parameters clearly changed the ballistic region characteristics, however, the impact became insignificant for outside of ballistic region, which means that the ballistic injection is mainly influenced by initial motion of injector needle.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1809-1812
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• 2006

In this paper, the thermally evaporated molybdenum oxide $(MoO_x)$ is investigated as the effective hole-injection material for organic lightemitting devices (OLEDs). The use of $MoO_x$ significantly lowers the operating voltage of OLEDs, insensitive to the anode materials used.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1532-1536
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• 2007

A plastic substrate with tiny rectangular pillars less than 100nm is injection molded to study pattern replication in injection molding. The size of the substrate is 50mm ${\times}$ 50mm and 1mm thick. The substrate has 9 patterned areas of which size is 2mm ${\times}$ 2mm respectively. The lengths of the pillars are 50nm, 100nm, 150nm and 200nm and the width and height are 50nm and about 100nm respectively. A pattern master is fabricated by e-beam writing using positive PR(photo resist) and then a nickel stamper replicated from the PR master by nickel electro-plating. Cr is deposited on the PR pattern master before nickel electro-plating as a conducting layer. Using this nickel stamper, several injection molding experiments are done to investigate effects of the injection molding parameters such as mold temperature, injection rate, packing pressure or pattern location on the replication of the patterns under 100nm.

• Journal of Acupuncture Research
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• v.33 no.1
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• pp.9-21
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• 2016

Objectives : The aim of this study was to investigate the effect of low frequency electro-acupuncture at ST39 on intestinal motility in rats. Methods : Intestinal hypermotility and hypomotility in rats were induced by oral carbachol ingestion and loperamide injection. Rats were divided into seventeen experimental groups including the normal and holder groups. The rats were induced with intestinal hypermotility and hypomotility and divided into pre and post-treatment groups. I also carried out acupuncture (needle retention) and low frequency electro-acupuncture at ST39 or the sham point. I fed charcoal to rats after the treatment and calculated its distance travelled in the gastrointestinal tract, which was compared by groups so as to determine which treatment was more effective in increasing or decreasing intestinal motility. Results : 1. In normal rats, low frequency electro-acupuncture at ST39 showed no significant effect on intestinal motility. 2. Pre-treatment with acupuncture (needle retention) at ST39 on intestinal motility over-activated with carbachol significantly decreased intestinal motility in rats. 3. Pre-treatment with low frequency electro-acupuncture at ST39 on intestinal motility over-activated with carbachol significantly decreased intestinal motility in rats. 4. Pre-treatment with acupuncture (needle retention and low frequency electro-acupuncture) at ST39 showed no significant effect on intestinal hypomotility in rats that was induced by loperamide injection. Conclusions : These results suggest that acupuncture (needle retention) and low frequency electro-acupuncture at ST39 have preventive effects on intestinal hypermotility. Regardless of the stimulation method, ST39 showed an effect on intestinal motility. Further study is required to confirm other effects of ST39.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.5
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• pp.660-665
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• 2001

Ultrafine particles have been widely used in many high technology industrial areas. The spherical nonagglomerated and uniform nanometer-size SiO$_2$particles are synthesized by the direct injection of TEOS(Tetraethyorthosilicate) using electro-hydrodynamic spraying method. Electro-hydrodynamic spraying can generate submicron-size TEOS droplets having high electric charges by applying a high electric field between the liquid injection nozzle and the reaction tube. These TEOS droplets are evaporated, and thermally decomposed or oxidized to produce nanometresized SiO$_2$particles in the reaction tube. Spherical, nonagglomerated and ultrafine particles are generated in various conditions and examined by using SEM and SMPS. As the total gas flow rate in the furnace changes from 1.5 lpm, the mean diameter of SiO$_2$particle decreases from 120 nm to 68 nm. The synthesized particle charging fractions are also investigated.

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1153-1164
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• 2016

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.174-179
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• 2000

Ultrafine particles have been used widely in many high technology industrial areas. The spherical nonagglomerated and uniform nanometer-size $SiO_2$ particles are synthesized by the direct injection of TEOS(Tetraethyorthosilicate) using electro-hydrodynamic spray ins method. Electro-hydrodynamic spray can generate in the range of submicron-size TEOS particles with high electric charge by applying a high electric field between the liquid injection nozzle and the reaction tube. This TEOS particles are thermally decomposed or oxidized to produce nanometresized $SiO_2$ particles in the reaction tube. Spherical, nonagglomerated and ultrafine particle generated and examined at furnaced temperature, $800^{\circ}C$ and TEOS flowrate of 0.49 or $1.00cm^3/hr$ using SEM and SMPS. As the total gas flowrate changes from 1.51pm to 5.01pm, the mean diameter of $SiO_2$ particle decreases from 120 nm to 68nm.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.2 no.1
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• pp.65-74
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• 1988

For experiment, we made the electro chemical display element with the NESA glass of display electrode which had low resistance. Density of injection charge, optical density and response characteristics were observed through coloring and achromatizing phemomena in the display element As optical electric chemical reaction was occured in $WO_3$ and cell, it was possible to repeat colouring and achromatizing, and the colouring characteristics was good. And the higher colouring and achromatizing voltage, the lower resistance of electrode and the thinner $WO_3$film was, the better response characteristics. With analyzing phenomena of electro chromism, we could find the possibility of practical use of the coloring and achromatizing element for clock, instrument and guide plate.

• Transactions of The Korea Fluid Power Systems Society
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• v.8 no.4
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• pp.1-8
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• 2011

Injection molding machine is the assembly of many kinds of mechanical and fluid power part and electro-electronic control system. From in these, fluid power is a part where becomes the first core of this machine. Fluid power systems of injection molding machine are modelled and analyzed using a commercial program AMESim. The analysis model which is detailed about the parts applied a publishing catalog data. Sub system models which is divided according to functional operation are made and its analysis results shows how design parameters work on operational characteristics like displacement, pressure, flow rates at each node and so on. Total fluid power circuit model is also made and analyzed. The results made by analysis will be used design of fluid power circuit of injection molding machine.