• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1089-1092
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• 2007

New display technologies including LCD and plasma panels and Digital Light Projection (DLP) systems all offer large screens and impressive picture quality. However, flat-panel displays require a sophisticated picture processing to let these panels perform at their optimum levels. This paper explains why motion compensating techniques combined with frame rate conversion and quasi-impulse driving reduces motion blur and film judder for flat panel displays and presents the IC and its system application using this technique.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.4
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• pp.308-315
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• 2007

This study is performed to find out the climb performance of light airplane, Chang Gong-91, as a part of flight test to acquire the certification. Chang Gong-91 is a 5-passenger light aircraft of normal category with single reciprocating engine, and the first officially certified by Korean Ministry of Construction and Transportation in 1993. These flight test procedure and data for climb performance are used to get type certification. We have got maximum climb rate for operating altitude, best angle of climb speed, best rate of climb speed, and absolute ceiling of Chang Gong-91 using drag polar data reduction method from sawtooth climb flight data. Also we compare the form drag coefficient from the results of climb performance and Oswald's effectiveness coefficient to design values using lift-drag curve of light airplane.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.8
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• pp.34-42
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• 1999

In late 1997, the portion of registered light-duty diesel vehicle was 25.3% and its emission rate was 17.1% in Korea. Especially, diesel particulate matters(DPM) and NOx are hazardous air pollutants to human health and environment in urban area. The reduction technologies of exhaust emissions from diesel engines are improvement of engine combustion, fuel quality and development of diesel exhaust after treatment , In this study , a light-duty diesel oxidation catalyst(DOC) that is one of the diesel exhaust after treatment was made for performance evaluation and the emission characteristics were tested on CVS-75 mode. And the analysis of the particle size distribution with scanning mobility particle 100, 67.6% and 66.7, 10.0% for Pt and Pt-V catalyst .And for Pt catalyst, the PM increased 7.8% because of increasing sulfate but Pt-V catalyst reduced the PM to 23.0% . Test results of particle size distribution showed that peak values of number and mass densities are respectively 100∼200nm their distribution trend independent of vehicle speed.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.24-31
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• 2002

An experimental study was conducted to investigate the effects of EGR (Exhaust Gas Recirculation) variables on performance and emission characteristics in a 2-liter 4-cylinder spark-ignition LPG fuelled engine. The effects of EGR on the reduction of thermal loading at exhaust manifold were also investigated because the reduced gas temperature is desirable for the reliability of an engine in light of both thermal efficiency and material issue of exhaust manifold. The steady-state tests show that the brake thermal efficiency increased and the brake specific fuel consumption decreased with the increase of EGR rate in hot EGR and with the decrease of EGR temperature in case of cooled EGR, while the stable combustion was maintained. The increase of EGR rate or the decrease of EGR temperature results in the reduction of NOx emission even in the increase of HC emission. Furthermore, decreasing EGR temperature by $180^{\circ}C$ enabled the reduction of exhaust gas temperature by $15^{\circ}C$ in cooled EGR test at 1600rpm/370kPa BMEP operation, and consequently the reduction of thermal load at exhaust. The optimization strategy of EGR application is to be discussed by the investigation on the effect of geometrical characteristics of EGR-supplying pipe line.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.16-22
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• 2007

This study was carried out to investigate the effects of shading conditions for appropriate light level for several floricultural plants native to Korea. The results under the different shading levels of 0, 30, 50, 60% and full sun light are as follows; Growth of Miscanthus sinensis and Pennisetum alopecuroides, which are heliophyte plants, were better under 30% shading condition than full sunlight. Higher shading levels was poor than control. Growth of Sedum spectable was decreased when light intensity was decreased. As shading level increased, growth reduction rate in Sedum spectable were higher than that of other species. Growth and ornamental value of Arisaema amurense, which is sciophyte plants, were increased under 50% shading.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.131-136
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• 2002

In recent year, it has been investigated on the reduction of mass of structures for the purpose of the larger space and the economy with the industry developing very fast and qualitatively. So the purpose of this study is to investigate the manufacture of light weight concrete panel using the artificial light-weight aggregate as a part of the substitution of foamed styrene and polyurethane because of narrow allocable temperature zone in use. The compressive strength, flexural strength, unit weight, absorption test and thermal conductivity were practised at 3, 7 and 28 days after manufacturing the light-weight concrete lot the panel core: the filling ratio of continuous void was defied as 40%, 50%, and 60% and water-cement rate was 35, 40 and 45%. As a result of this, it was revealed that the mixture derived from filling ration of void of 50% and water-cement ratio 40% were developing the best properties of the others.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.225-231
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• 2005

This study was carried out to observe the stability of riboflavin in dietary supplements. Dietary supplements were in the type of tablet, powder, capsule and liquid. Various factors on the stability of riboflavin such as effect of light, storage temperature and time were examined using HPLC method. Samples were exposed to various temperatures (-9, 4, $30^{\circ}C$) and light at room temperature far 9 months. As well as storage period became longer, reduction rate constant of riboflavin increased. Riboflavin reduction rate constants were higher during storage with light than without light. And there was a significant difference of reduction rate constants in types of dietary supplement. In other words, riboflavin in tablet types was significantly more stable than the others, and liquid type was the most unstable. Therefore, type, light, and packing container of dietary supplements containing riboflavin would be considered in order to establish their appropriate shelf lives. In consideration with riboflavin decrease in dietary supplements, riboflavin would be appropriate for the nutritional labelling guide when predicting them at the end of shelf lives.

• The Plant Pathology Journal
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• v.16 no.5
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• pp.257-263
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• 2000

Infection with rice blast fungus (Magnaporthe grisea) significantly reduced foliar net photosynthesis (A) of rice cultivars: Ilpoom, Hwasung, and Choochung in greenhouse experiments. By measuring the amount of diseased leaf area with a computer image analysis system, the relation between disease severity (DS) and net photosynthetic rate was curvilinearly correlated (r=0.679). Diseased leaves with 35% blast symptom can be predicted to have a 50% reduction of photosynthesis. The disease severity was linearly correlated (r=0.478) with total chlorophyll (chlorophyll a and chlorophyll b) per unit leaf area(TC). Light use efficiency was reduced by the fungal infection according to the light response curves. However, dark respiration (Rd) did not change after the fungal infection (p=0.526). Since the percent of reduction in photosynthesis greatly exceeded the percent of leaf area covered by blast lesions, loss of photosynthetic tissue on an area basis could not by itself account for the reduced photosynthesis. Quantitative photosynthetic reduction can be partially explained by decreasing TC, but cannot be explained by decreasing Rd. By photosynthesis (A)-internal CO$_2$ concentration (C$_i$ curve analysis, it was suggested that the fungal infection reduced ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, ribulose-1,5-bisphosphate (RuBP) regeneration, and inorganic phosphate regeneration. Thus, the reduction of photosynthesis by blast infection was associated with decreased TC and biochemical capacity, which comprises all carbon metabolism after CO$_2$ enters through the stomata.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.377-381
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• 2006

A study was carried out to determine a suitable light intensity and inoculum size for the growth of Rhodopseudomonas palustris strain B1. The pollution reduction of sago effluent using free and immobilised R. palustris cells was also evaluated. The growth rate in glutamatemalate medium was highest at 4 klux compared to 2.5 and 3 klux. The optimal inoculum size was 10% (v/v). Both the COD and BOD of the sago effluent were reduced by 67% after three days of treatment. The difference in biomass production or BOD and COD removal with higher inoculum sizes of 15 and 20% was minimal. This could be attributed to limited nutrient availability in the substrate. The use of immobilised cells of R. palustris reduced the pollution load 10% less compared to pollution reduction by free cells. Hence, there was no significant difference in using free or immobilised cells for the treatment of sago effluent.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.2
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• pp.112-119
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• 2016

Many studies have been conducted on the performance of a passive autocatalytic recombiner (PAR), but not many have focused on the locations where the PAR is installed. During a severe accident in a nuclear reactor containment, a large amount of hydrogen gas can be produced and released into the containment, leading to hydrogen deflagration or a detonation. A PAR is a hydrogen mitigation method that is widely implemented in current and advanced light water reactors. Therefore, for this study, a PAR was installed at different locations in order to investigate the difference in hydrogen reduction rate. The results indicate that the hydrogen reduction rate of a PAR is proportional to the distance between the hydrogen induction location and the bottom wall.