• Journal of Photoscience
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• 제3권1호
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• pp.23-28
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• 1996

To investigate the structure and function of photosystem I, cartridge mutagenesis technique was used to inactivate the psaB gene of photosystem I. From the screen, many strains which have potential defects in photosystem I were generated. Biochemical analysis revealed that B2, one of the mutant, had a reduced amount of chlorophyll. Electron transfer activitx from photosystem II to photosystem I as oxygen uptake was the rate of 64 % of wild type. Also B2 showed a decreased photosystem I activity when measured by 77 K fluorescence emission spectrum. Particularly, immunodetection analysis showed that the B2 had reduced amount of PsaA/PsaB, but a normal range of PsaC and PsaD. Here we present a photoheterotrophic mutant for psaB gene as a unique model strain for future study of structural/functional relationship and biogenesis of photosystem I.

• 동력기계공학회지
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• 제13권4호
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• pp.5-10
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• 2009

Urea-SCR system, the selective catalytic reduction using urea as reducing agent, is a powerful technique to reduce nitrogen oxides(NOx) emitted from diesel engines. However, a tank of urea(32.5 wt%)-water solution can be frozen in low ambient temperature levels of below $-11^{\circ}C$. The purpose of this study is to understand freezing and melting phenomena of the urea-water solution, and its can be applied to get the urea-water solution from frozen it within 5 minutes after cold start. Factors considered were the type of heater and the urea tank shape. From the results, it was found that melting volume of cartridge heater B during 5 minutes of heating period was 83ml when supplying electric power of 150W. Horizontal heater B, which was put in the narrow bottom space of the tank T1, had fast melting characteristics.

• 전자공학회논문지D
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• 제35D권4호
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• pp.78-83
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• 1998

A small size cartrideg for FET type electrolyte sensor is designed and faricated with much simplified process by using micromachining tenchiques such as silicon etching andglass bonding. Size of the whole cartideg is 2.4cm*2.5cm, and the dead volume of a micro flow-channel in the cartrideg is only 8.5.mu.l. The photosensitive polymer(THB 30) is used to define a micropool and to encapsulate the sensor surface for standardizationof electrolyte sensors. To miniaturize micro flow-channel conventional reference electrode(Ag/AgCl) a differential amplification is introduced using REFET and quasi reference electrode. Refet was fabricated using photosensitive polymer(OMR 83). The fabricated cartridge with built-in pH-ISFET showed good operational characteristics such as linearity and high sensitivity (55.4mV/pH) in a wide pH range(pH2-pH12).

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권4호
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• pp.176-180
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• 2004

This paper presents the fabrication and test of a micro cell exciter actuated by an electromagnetic force for the study on the chondrogenic differentiation of rabbit mesenchymal stem cells (MSCs). The micro cell exciter is designed to apply compressive loading to the alginate gel mixed with the MSCs. The magnetic cell exciter consists of an actuator component and a cartridge-type chamber component. An actuator is composed of a permanent magnet, a core and a coil. The chamber has seven PMMA wells and a cell culture Petri dish. Two types of alginate gels were stimulated by the cell exciters for 10 minutes every 12 hours for 7 days. In order to determine the expression of these matrix components during differentiation, RT-PCR analysis was performed. Collagen type II was expressed in the MSCs subjected to the compressive stimulation.

• 한국기계가공학회지
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• 제20권2호
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• pp.38-44
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• 2021

To cater to the transition from single-color to multicolor/multi-material printing, this paper proposes a cartridge-replacing type multi-nozzle Fused Depositon Modeling(FDM) three-dimensional (3D) printer. In the test printing run, tool change failure/wobble/layer shift occurred. It was confirmed that improper support was the cause of this tool change failure. As a solution, spline and electromagnetic cartridges were designed. Wobble was caused by machine vibration and the motor stepping out. To minimize wobble, an additional Z-axis was installed, and the four-point bed leveling method was used instead of the three-point bed leveling method. The occurrence of layer shift was ascribed to the eccentricity of the Z-axis lead screw. Therefore, slit coupler was replaced with an Oldham type. In addition to the mechanical supplementation, the control environment was integrated to prevent accidents and signal errors due to wire connections. Before the final test printing run, a rectifier circuit was added to the motor to secure precise control stability. The final test printing run confirmed that the wobble/layer shift phenomenon was minimized, and the maximum error between layers was reduced to 0.05.

• 한국건설순환자원학회논문집
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• 제4권4호
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• pp.396-403
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• 2016

본 연구에서는 지하 콘크리트 구조물에 누수 발생 시 콘크리트 배면에 주입하여 보수를 시행하는 1액형 점착 실링재에 대해 알아보고 새로운 콘크리트 배면 주입재인 2액형 점착 실링재에 대한 평가를 진행하였다. 2액형 점착 실링재는 아스팔트 계열의 주제와 라텍스 계열의 증점제로 구성된 실링재이며, 주제와 증점제의 배합비에 따라 실링재의 점도편차가 크게 나타났다. 이에 주제와 증점제의 배합비를 투수시험을 통해 확인한 결과 주입성, 경제성, 성능을 고려하여 적정배합비를 6:1로 정하고 KS F 4935 평가를 진행하였다. 2액형 점착 실링재는 static mixer를 활용한 카트리지 타입의 용기를 이용하여 주입이 가능하고 KS F 4935 시험방법에 따라 평가를 진행한 결과 KS 기준을 만족하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.1864-1869
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• 2007

In this study, we compare thermal performance between four different types of cold plates for humanoid robot cooling. Two commercially available cold plates made of copper have different dimensions and internal flow paths: One has $20{\times}20$ $mm^2$ base area with micro-channels and the other has $62.5{\times}62.5$ $mm^2$ base area with 85 round pin-fins. And two different types of cold plates of $20{\times}20$ $mm^2$ base area with 7 mm high are made of PC (polycarbonate), which aims to reduce the weight of cooling system. All cold plates are mounted on a $20{\times}20$ $mm^2$ copper block with two cartridge heaters of 30 $W/cm^2$. The overall heat transfer coefficient and thermal resistances for the liquid-cooled cold plates are obtained. The copper cold plate with micro-channels showed the best performance. Polycarbonate cold plates display fairly good thermal performance with more reduced system weight.

• 한국입자에어로졸학회지
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• 제6권4호
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• pp.173-183
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• 2010

The high temperature pleated filter bags which were used during this study were made of pleated nonwoven fabric of heat and acid resistant polysulfonate fibers which can withstand the heat up to $300^{\circ}C$ and have a filtration area which is 3 to 5 times larger than the conventional round filter bags. Cartridge module packed with 3 kind of the sulfur impregnated activated-carbon based sorbents were inserted in the inner of the pleated filter bag. This type of pleated filter bag was designed to remove not only the particulate matter but also the gaseous elemental mercury. The electrostatic precipitator part can enhance the particulate removal efficiency and reduce the pressure drop of the pleated filter bag by agglomerated particles to form a more porous dust layer on the surface of the pleated bag which is increased the filter bag cleaning efficiency. In addition, the most of particles are separated from the flue gas stream through the cyclone and the electrostatic precipitator part which were installed at the lower part and main body part of the convergence particulate collector, respectively. Thus reduce particulate loading of the high temperature pleated filter bags were applied in this study to analyze the removal characteristics of particulate matter and gaseous elemental mercury.

• 전기화학회지
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• 제15권4호
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• pp.249-255
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• 2012

크레아티닌 센서의 생체시료 측정 시 가장 심각한 방해 작용을 발생하는 물질인 크레아틴을 효과적으로 제거하기 위하여 creatine kinase와 adenosine triphosphate를 사용한 두 번째 효소층을 도입하여 크레아틴에 대한 방해작용을 현저히 감소시켰다. 또한 평면형 소형 크레아티닌 센서를 개발하기 위해 탄소전극 표면에 Pt black(Pt-B)을 도입하여 표면적을 증가시킴으로써 전기화학적 감응 특성을 증가시킨 스크린 프린팅 방식의 Pt-B/C 전극을 제작하였다. 최적화된 소형 크레아티닌 센서를 흐름계 카트리지에 장착하여 미지시료를 측정한 결과 5% 이내의 오차 범위 내에서 우수한 측정 정확성과 재현성을 보임을 확인하였다.

• 한국전산유체공학회지
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• 제22권1호
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• pp.26-36
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• 2017

A numerical study has been performed to evaluate thermal-hydraulic performance of a finger type cooling module with multiple-jet impingement in a divertor of nuclear fusion reactor. To analyze conjugate heat transfer in both solid and fluid domains, numerical analysis of the flow using three-dimensional Reynolds-averaged Navier-Stokes equations has been performed with shear stress transport turbulence model. The computational domain for the cooling module consisted of a single fluid domain and three solid domains; tile, thimble, and cartridge. The numerical results for the temperature variation on the tile were validated in comparison with experimental data under the same conditions. A parametric study was performed with four geometric parameters, i.e., angles between x-axis and centerlines of hole 1, 2, 3 and 4. The results indicate that the heat transfer rate was increased by 2.7% and 0.7% by the angle ${\theta}_1$ and angle ${\theta}_2$, respectively, and that the pressure drop was decreased by up to 1.8% by the angle ${\theta}_3$.