• Journal of Aerospace System Engineering
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• v.11 no.5
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• pp.36-41
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• 2017

As the space debris in the satellite orbit increases, the risk of collision between the currently operating satellites and the space debris is continuously increasing. Therefore, in this study, we designed one-degree-of-freedom capture device using simple deployment mechanism. The capture device consists of four link groups connected with net. To increase the reliability, each link group is connected to one driving part so that the total degree of freedom is 1. In addition, the links were stowed on each side of the satellites so that they would not affect the janitor satellite mission. Finally, to confirm the possibility of deployment in the space environment, we carried out deployment experiments in water similar to the microgravity environment, and confirmed the deployment of capture device and the possibility of capturing target satellite.

• Korean Journal of Organic Agriculture
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• v.28 no.3
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• pp.405-415
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• 2020

In order to effectively control the Ricania sp., we investigated the light response to adults and developed an adult capturing device using light with superior attractiveness. The preference among six light sources such as daylight color, green, etc. for the Ricania sp. adult was favored with daylight color 97 > black 79 = red 79 = blue 79 > green 24 > yellow 13. We have developed an adult catching device using the most preferred daylight colors and behavioral habits of the Ricania sp.. The capture device consisted of two daylight compact lamps (30W, 20W), a yellow plate, and a catcher using water, and caught about 700 individuals a day. The capturing device has a large amount of capturing because adult is activity at high nighttime temperatures, but the capturing amount decreased significantly when the temperature dropped below 23℃. More than 85% of the Ricania sp. adults were trapped for 3 hours from 19:00 to 23:00. Therefore, it is considered that the adult capturing device for the control of Ricania sp. is used from mid July to late August when the night temperature is over 23℃, and lights up from 19:00 to 23:00.

• Journal of Aerospace System Engineering
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• v.14 no.3
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• pp.10-16
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• 2020

We propose a capture mechanism based on the principles of fishing nets that can be mounted on the drone using cable. The gripper mechanism, mainly proposed for the drone is heavy, and is limited to catch standardized objects. In contrast, the proposed capture device in this paper is light, flexible, and can capture various types of objects from a long distance. The theoretical relationships between cables and mechanisms were analyzed. Finally, the capture device was designed and manufactured to be installed in the drone (DJI S900) to conduct capturing experiments for various objects and verify the validity.

• Korean journal of communication and information
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• v.65
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• pp.76-92
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• 2014

The purpose of this paper is to disclose the characteristics of SNS service platform in the perspective of 'dispositif'. To achieve this I extended Foucault's concept of 'dispositif' to the Internet and service platform of Google, Facebook. The platform dispositif is a complex of the interface services for the users, collection of data produced by users and the control of them. These three aspects are combined in the service platform modifying their modes in terms of time and space. This study would provide a critical approach toward the appropriation and control of user activities based upon platform.

• 전기의세계
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• v.38 no.5
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• pp.34-42
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• 1989

포항 방사광가속기의 입사장치인 2.5GeV 양전자 선형 가속기에서 양전자를 포획하는 solenoid lens와 접속용 사극자석의 system에 대하여 살펴보았다. 이론적 결과를 토대로 하여 이를 PLS 양전자 injector에 적용한 결과를 소개하고자 한다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.93.1-93.1
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• 2012

세라믹 고온초전도체는 에너지 저장장치의 핵심소재로 사용된다. 초전도 플라이휠 에너지 저장장치(Superconductor flywheel energy storage system)는 전기 에너지를 운동 에너지로 변환하여 저장하는 친환경, 고효율 에너지 저장장치이다. 에너지를 최소화하는데 사용되는 초전도 베어링은 고온초전도체와 영구자석으로 구성된다. 베어링에는 희토류계 초전도 물질(RE-Ba-Cu-O, RE:Rare-earth elements)가 사용된다. 베어링의 효율은 영구자석의 자력크기, 초전도체의 자기부상력과 포획자력에 비례한다. 에너지 저장효율을 높이려면 고온 초전도체의 임계전류밀도(초전도체 내부에 흘릴 수 있는 전기량)를 높이고, 초전도 결정립의 크기를 키워야 한다. 결정크기를 키우는 공정으로 종자결정성장법(Seed growth process)이 사용된다. 초전도체 제조공정은 분말의 성형, incongruent melting을 포함하는 부분 용융, 액상에서의 입성장, 포정반응을 통한 초전도 결정의 성장과정을 포함한다. 본 발표에서는 초전도 에너지 저장장치의 기본 원리, 초전도 베어링의 구성, 베어링용 초전도체의 제조방법과 특성(자기부상력과 포획자력) 평가기술, 차세대 에너지 저장장치로서의 초전도 플라이휠 에너지 저장장치의 전망에 대해 요약하였다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.1
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• pp.33-38
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• 2003

Turbidity meter calibrations were conducted using bottom sediment and suspended material collected with a vertical array of sediment traps at the coastal water off Gaduk Island. Compared to the bottom sediment comprising sand fraction of approximately 6％, trapped suspended material was composed entirely of silt and clay fractions and showed a tendency to get finer as elevation from the sea-bed increases. Slope parameter of linear regression due to bottom sediment was of minimum value and values of those due to suspended material increased gradually as the height of sediment trap increases (i.e., sediment size decreases). This result shows that turbidity meter calibration using bottom sediment can cause an overestimation error in the calculation of suspended sediment concentration and that the error can reach up to 25% in case of this study. Therefore, it is suggested that the use of a corrected calibration curve based on grain size distribution of suspended material instead of bottom sediment may reduce the measurement error of suspended sediment concentration.

• Electrical & Electronic Materials
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• v.6 no.3
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• pp.220-227
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• 1993

본 논문에서는 산화막의 두께가 23.angs.이며 질화막의 두께를 각각 530.angs., 1000.angs.으로한 캐패시터형 MNOS소자를 제작하고 기억특성을 비교, 분석하였다. 특성조사를 위해 자동 .DELTA. $V_{FB}$ 추적장치를 설계, 제작하여 사용하였다. 기억트랩밀도는 질화막 두께 530.angs.인 소자가 1000.angs.인 소자보다 0.18 x $10^{16}$ $m^{-2}$ 크며, 0.31 x $10^{8}$ V/m 낮은 산화막 전기장에서 전자가 주입되었으며 $10^{4}$sec경과후 포획전자의 유지율도 우수하였다. 또한 포획된 전자는 실리콘쪽으로의 역터넬링으로 인한 감쇠가 우세하게 나타났다. 펄스전압 인가에 따른 플랫밴드전압의 변화가 선형적으로 증가하는 영역에서는 산화막 전류가 지배적이었으며 포화하다 감소하는 영역에서는 질화막 전류의 영향이 컸다. 소거동작은 포획된 전자의 방출과 실리콘으로 부터의 정공주입이 동시에 일어남을 관측하였다.

• The Journal of the Korea Contents Association
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• v.4 no.2
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• pp.76-82
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• 2004

The thermal neutron capture cross-section (at 2,200 m/s value) of the $^{141}$Pr(n,$\gamma$)$^{142}$Pr reaction was measured by an activation method by using the heavy water ($D_2$O) thermal neutron facility at the KUR(Kyoto University Reactor). The thermal neutron fiux used in this experiment was monitored with the$^{197}$Au(n,$\gamma$)$^{198}$Au standard cross-section. The previous results and the evaluated data of JENDL-3.2, ENDF/B-VI, and JEF-2.2 were in good agreement with the current result.

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1047-1050
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• 2002