• Journal of IKEEE
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• v.18 no.3
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• pp.420-426
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• 2014

In this paper, we have implemented the low temperature fluidity test system with the composited fuel filter and heater, which has tested the low temperature fluidity of gasoline, an engine start time, the consumption of electricity and power to evaluate the system performance. The test condition have used the diesel fuel, the normal temperature, the diesel fuel supply pressure $3.4kgf/cm^2$ at $-20{\sim}-30^{\circ}C$, the fuel supply quantization 60 l/H, the setting current 30 A and the voltage $13V_{dc}$. In order to simulate the operation of diesel fuel filter, we will establish the composited fuel filter into test jig, and be filled with chamber tank and filter by a constant flow quantization and pressure. After these, it shall be cold for setting time. And then we have measured the consumption current and power of heater, an operating time and pressure of filter.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.3
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• pp.213-219
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• 2015

Piezoelectric-based hydraulic actuator is a hybrid device consisting of a hydraulic pump driven by piezoelectric stacks that is coupled to a conventional hydraulic cylinder via a set of fast-acting valves. Nowadays, such hybrid actuators are being researched and developed actively in many developed countries by requirement of high performance and compact flight system. In this research, a piezoelectric hybrid actuator has been designed and tested. To achieve bi-directional capabilities in the actuator, solenoid valves were used to control the direction of output fluid. The experimental testing of the actuator in uni-directional and bi-directional modes was performed to examine performance issues related to the solenoid valves. The results showed that the bi-directional performance was slightly lower than uni-directional performance due to air bubble developed in the valve system. A new design to solve the vacuum problem has been proposed to improve the performance of the hybrid actuator.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04a
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• pp.43-43
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• 1999

98년말 동일제지에 도입 설치된 Condebelt 설비는 세계 최초의 대형생산설비로 국제적 인 관심을 모으고 있다. 이러한 첨단 Condebelt 기술의 국산화를 위해서는 국내 원료 특성 에 적합하도록 공정최적화가 요청된다. 본 연구에서는 KOCC를 원료로 이용한 라이너지를 C Conde belt를 이용하여 생산할 경우 주요 공정변수에 따른 물성 변화를 평가하고, 이를 통하 여 Condebelt 공정을 최적화하고자 실험실용 파일로트 건조기를 이용하여 Condebelt 공정의 주요 변수가 지질에 미치는 영향을 검토하였다. 실험용 Condebelt 건조장치의 상부플레이트는 18WC까지, 하부플레이트는 냉각수를 이용 하여 40-80'C까지 조절이 가능하도록 설계하였으며, 유압을 이용하여 압체 압력과 시간을 변화시킬 수 있도록 하였다. 구축된 실험장치를 이용하여 Conde belt 공정의 주요 변수인 온도, 압력, 압체시간, 유입 지필의 건조도 변화에 따른 라이너지의 물성 변화를 평가하고 이를 실린더 건조된 종이의 물성과 비교하였다. 그 결과 본 연구에서 검토된 모든 건조조건에서 Conde belt 건조된 종이가 실린더 건조 된 종이보다 높은 강도를 나타내었으며, 투기저항성과 광택도 역시 향상되었다. 투기저항성 과 광택도는 강도적 성질과 달리 유입지 건조도가 높을수록, 상부플레이트의 온도가 높을수 록 그 효과가 저하되었다. 일반적으로 KOCC를 원료로한 라이너지를 Conde belt로 제조할 경우 상부 고온챔버의 온도를 160'C, 압체압력을 5 bar로 조절하는 것이 가장 좋을 것으로 판단되었다. 원료펄프의 조성에 따른 Condebelt 공정의 건조효과를 연구한 결과 모든 펄프에서 공히 C Condebelt 건조방법이 실린더 건조방법에 비하여 물성 향상 효과가 있는 것으로 나타났으 며, 그 효과는 펼프의 리그닌 함량이 높을수록 크게 나타났다. 또 Condebelt의 물성개선 특 성을 이용한 원료비 절감 가능성을 평가하기 위해 AOCC와 KOCC를 이용하여 단층지와 이 층지를 제조하고 물성을 비교평가하였다. 그 결과 Condebelt를 이용하면 KOCC의 비율을 증가시키더라도 AOCC만을 이용하여 실린더 건조한 종이보다 우수한 물성을 얻을 수 있었다. 이러한 연구를 통하여 Condebelt 공정이 국내 저급원료로 제조된 종이의 강도 저하를 극복할 수 있는 기술임을 확인하였다.

• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.370-378
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• 2015

The data acquisition unit, signal acquiring and processing equipment, processes and provides major data of an aircraft such as engine system, power train system, hydraulic system, etc. However, it had lots of failure related to the system during production test flight, and it is necessary to fix them perfectly as soon as possible because of the significance of the equipment. In this paper, it contains failure classification and analysis for each defect element to improve whole software as well as electrical circuit. Particularly, utilizing Fault Injection Method based interworking test, more efficient improvement activity was performed for not only equipment level but also aircraft level, and as a result, it is achieved that considerable betterment of Surion quality and flight safety.

• Journal of the Korea Convergence Society
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• v.10 no.12
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• pp.293-298
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• 2019

The global market for temperature sensors for power plants is estimated at around 35 billion won, of which South Korea relies on imported products for more than 95 percent. This study is that a temperature measurement device for gas turbine rotators for power plants and can be applied to more than 800 of 100 MW gas turbine generators operating in Korea. This study has improved durability by changing the shape of the measuring part, structure of the connecting part, and material changes, and is a component technology applicable to other measuring devices such as humidity, gas and hydraulic pressure used in precision chemical process and plant export industry. As a result of this study, temperature sensors designed as three types of sensors for measuring the temperature of the gas turbine for power plants met Class 1 temperature accuracy in the range of 0℃ to 300℃, and improved durability significantly compared to similar products.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.7
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• pp.919-928
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• 2010

Four patterns for width adjustment were studied with an aim to increase the width-adjustment speed in continuous casting. The main goals are to minimize the actuating force of a WAM actuator, to develop a deformation analysis model of a solidified shell in the mold, and to induce the main limit factor for the speedup of width adjustment. On the basis of the width-adjustment experiment, the notable features of four patterns types were considered, and we compared the corresponding actuating forces. For comparing the driving forces of the patterns, during the experiment, the same casting speed was maintained for each pattern. To optimize the parameter of the deformation analysis model of the solidified shell, the experiment results were applied to them. To speed up width adjustment and to reduce the driving force, we controlled the pattern parameters. The most effective pattern was the fast-mode pattern, and the taper was the main parameter that helped reduce the driving forces during the motion of the actuator.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.3
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• pp.17-22
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• 2003

This paper presents an experimental investigation of a reversible colloidal seismic damper, which is statically loaded, The porous matrix is composed from silica gel (labyrinth or central-cavity architecture), coated by organo-silicones substances, in order to achieve a hydrophobic surface. Water is considered as associated lyophobic liquid. Reversible colloidal damper static test rig and the measuring technique of the static hysteresis are described. Influence of the pare and particle diameters, particle architecture and length of the grafted molecule upon the reversible colloidal damper hysteresis is investigated, for distinctive types and mixtures of porous matrices, Variation of the reversible colloidal damper dissipated energy and efficiency with temperature, pressure, is illustrated.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.11
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• pp.141-145
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• 1992

심부전 환자의 심근회복을 도울 수 있는 장비인 전기유압방식 좌심실보조기를 개발하였다. 좌심실보조기는 혈액펌프, 압력펌프, 제어기로 구성되어 있으며, 혈액펌프에 내장된 혈액주머니는 동물실험을 위하여 50 ml의 크기로 제작하였다. 좌심실보조기의 성능평가를 위하여 최대 박출량을 측정하고 있으나 실험실에서 측정된 간은 동물 실험에서 관찰되는 것보다 일반적으로 증가된 박출량을 보이게 된다. 이는 생체에서는 좌심방의 체적이 박동 주기에 따라 변하여 좌심실보조기가 받아들일 수 있는 유효 혈액량이 변하는 반면, 모의순환장치에서는 좌심방을 단순 저장고로 사용하기 때문에 좌심방의 박동주기에 따른 체적변화를 감안하지 못하여 생기는 것이다. 본 실험에서는 모의순환 장치에 체적변화 가능한 100ml 크기의 좌심방을 연결하여 좌심방으로 들어오는 혈류량이 제한된 동물실험 상황을 모방하였다. 좌심실보조기의 제어방식중 수측기 이완기 비율(SD 비율)변화에 따른 좌심방 음압발생효과를 관찰한 결과 SD 비율을 40 %로 유지하면 행정거리가 클때도 좌심실의 음압발생을 줄일 수 있는 것을 관찰하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.2
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• pp.59-66
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• 2003

A novel application of nano-technology in the field of engineering, called colloidal damper, is investigated. This device is complementary to the hydraulic damper, having a cylinder-piston construction. Particularly for colloidal damper, the hydraulic oil is replacedby a colloidal suspension, which is consisted from a nano-porous matrix with controlled architecture and a lyophobic fluid. In this experimental work, the porous matrix is composed from silica gel, with labyrinth architecture, coated by organo-silicones substances in order to achieve a hydrophobic surface. Water is considered as associated lyophobic fluid. The colloidal damper test rig and the measuring technique of the hysteresis are described. the influence of the hydrophobicity level upon the colloidal damper hysteresis is investigated, for silica gels with similar pores distribution. A certain desired shape of the hysteresis can be achieved by employing mixture of silica gels with different level of hydrophobicity and/or architecture. With these results, it is believed that the proposed damper can be designed and be applied to the desired structure.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2609-2614
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• 2007

Shell & Tube type Oil Cooler is widely used for hydraulic presses, die casting machines, generation equipments, machine tools and construction heavy machinery. Temperature of oil in the hydraulic system changes viscosity and thickness of oil film. They have a bad effect to performance and lubrication of hydraulic machinery, so it is important to know exactly the heat exchanging efficiency of oil cooler for controlling oil temperature. But most Korean manufacturers do not have test equipment for oil cooler, so they cannot carry out the efficiency test of oil cooler and it is impossible to verify its performance. This paper includes information of construction of necessary utilities for oil cooler test and design and manufacture of test equipment. One can select the optimum product by obtaining performance data through tests of various kinds of oil coolers. And also the paper developed a program which can be easily used for design of 2D and 3D drawings of oil cooler.