• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.3
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• pp.315-323
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• 2004

An electrical cascade impactor is a multi-stage impaction device to separate airborne particles into aerodynamic size classes using particle charging and electrical detection techniques. A Faraday cage and an aerosol charger, which are basic components of the electrical cascade impactor, were designed and evaluated in this study. The low-level current response of the Faraday cage was investigated with changing particle size and air flow rate by using sodium chloride (NaCl) particles. The response of the prototype Faraday cage was very similar to that of a commercial aerosol electrometer (TSI model 3068) within ${\pm}$5% for singly-charged particles. The response linearity of the prototype Faraday cage could be extended up to flow rate of 30 L/min. For the performance evaluation of the aerosol charger the monodisperse liquid dioctyl sebacate (DOS) particles, with diameters of 0.1∼0.8$\mu\textrm{m}$, were generated using spraying from an atomizer followed by evaporation-condensation process. Typical performance parameters of the aerosol charger such as P$.$n, wall loss, and elementary charges per particle were evaluated. The performance of the prototype aerosol charger was found to be close to that of the aerosol charger used in an electrical low pressure impactor (ELPI, Dekati).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.869-870
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• 2009

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.5 s.120
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• pp.563-568
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• 2007

In this paper, the proposed package antenna, which is meander line structure with short pin, is miniaturized to realize RF-SoP at 900 MHz RFID band. The RFID BGA(Ball Grid Array) chip is put in a cavity of LTCC Layers. The coupling and cross talk, which are happen between BGA chip and proposed package antenna, are reduced by faraday cage, which consists of ground and via fences, is realized to enhance the isolation between BGA chip and antenna. The proposed antenna structure is focused on the package level antenna realization at low frequency band. The novel proposed package antenna size is $13mm{\times}9mm{\times}3.51mm$. The measured resonance frequency is 0.893 GHz. The impedance bandwidth is 9 MHz. The maximum gain of radiation pattern is -2.36 dBi.

• Resources Recycling
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• v.22 no.1
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• pp.29-35
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• 2013

The study on the recovery of Nylon from a radiator of End-of-Life Vehicle was conducted by using triboelectrostatic separation technique. For the effective separation of the sample(Nylon, PP glass), charge polarity and amount of each sample with various charging materials have been investigated by faraday cage. And then, charging material was selected as carrying out basic separation experiments with materials that can be possible to polarize samples. Finally, the continuos type triboelectrostatic separator was developed with selected charging material and the recovery possibility of the sample was confirmed as carrying out various separation experiments.

• Asian Journal of Atmospheric Environment
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• v.9 no.2
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• pp.137-145
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• 2015

This study focused on the measurement of the actual charging state of ambient aerosol particles, which is important for understanding the intricate process of adverse health effects caused by particulate matter (PM). The net electrostatic charging state of $PM_{2.5}$ collected on filter media was measured in this study. The Faraday cage method and surface potential measurements were used in this study. The results showed that the polarities of the net charging state measured using these two methods were in agreement for 42 out of 48 samples (87.5%), and 36 samples (75%) were negatively charged. The filters were not significantly charged by friction between the filters and air not containing PM. Charge addition to or leakage from the filters was not observed over a two-month storage period. Net charging state of $PM_{2.5}$ collected on the filters was concluded to be negative in most cases, based on data's support of the assumption that aerosol charging state is not altered by the process of PM collection using filter.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1995.05a
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• pp.171-175
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• 1995

Semiconductor diode lasers that can generate one watt or more of optical energy for tens of milliseconds (quasi continuous wave) are now readily available. Several researchers have demonstrated that this power level, when properly coupled, can reliably initiate pyrotechnic mixtures. This means that the initiator containing the pyrotechnic can be protected against inadvertent initiation from electromagnetic radiation or electrostatic discharge by a conducting Faraday cage surrounding the explosive. Only a small dielectric window penetrates the housing of the initiator, thereby eliminating the conductors necessitated by a bridgewire electroexplosive device. The diode laser itself, however, functions at a low voltage (typically 3 volts) and hence is susceptible to inadvertent function from power supply short circuits, electrostatic discharge or induced RF energy. The rocket motor arm-fire device de-scribed in this paper uses a diode laser, but protects it from unintentional function with a Radio Frequency Attenuating Coupler (RFAC).The RFAC, invented by ML Aviation, a UK company, transfers power into a Faraday cage via magnetic flux, thereby protecting the diode, its drive circuit and the pyrotechnic from all electromagnetic and electrostatic hazards. The first production application of a diode laser and RFAC device was by the Korean Agency for Defense Development.

• Resources Recycling
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• v.11 no.3
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• pp.37-45
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• 2002

Triboelectrostatic Separation procese is a technology that different particles charged after contact and rubbing different materials are separated in an electric field. At this time, charged polarity of different materials depends on their own work function. Therefore this study discovers work functions of various plastics and determines charging characteristics for the specific optimum operation condition. The experiment is conducted with two sample sets composed of various different plastics. Each sample is charged by contact and rubbing different materials. Surface charge of charged particles is measured by Faraday Cage. The specific work function of an each plastic is driven by measured charging amount and charged particles are separated in a certain electric field ($\pm$20 kV). At last, the relationship between charging amount and separation efficiency is induced by the separation experiment.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.117-118
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• 2000

대전 입자의 거동은 입자의 제어 측면뿐만 아니라 입자의 측정에서 중요한 요소 중 하나이다. 특히, 입자를 실시간으로 측정하는 경우 입자의 대전량을 정밀하고 정확하게 측정하는 것은 측정 대상이 심하게 변할 때 매우 중요하다. 입자의 전기적 특성(대전량)을 이용하여 입경분포를 측정하는 장비로는 EAA(electrical aerosol analyzer), SMPS(scanning mobility particle sizer), ELPI(electrical low pressure impactor) 등이 있다. (중략)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.329-333
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• 1996

In this Paper, the streaming electrification of transformer oils generated at the interface of transformer oils and the AC breakdown with impurity is studied. The electrification current is measured by the electrometer connected the faraday cage. And a oil velocity is maintained equally. In case of the AC breakdown test, the temperature are 30[$^{\circ}C$], 50[$^{\circ}C$], 80[$^{\circ}C$] and 90[$^{\circ}C$], repetitively. As a result of breakdown experiment, the dielectric breakdown strength is decreased in low temperature region and is increased in high temperature region according to increase of contained sodium. In case of streaming electrification experiment, the streaming current is more increased with the specimen contained sodium than the original specimen.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.135.2-135.2
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• 2012

일반적으로 전자파챔버는 패러데이 케이지(Faraday Cage)라고 불리는 금속재질의 차폐구조물과 구조물 내부에서 발생할 수 있는 전자파의 반사를 억제하는 전파 흡수체로 구성되어 있다. 전자파 환경시험의 무결성을 유지하기 위해서는 챔버 내부에서 발생하는 전자기파가 외부로 나가는 것이 차단되어야 하며 역으로 챔버 외부에서 발생하는 전자기파도 챔버 내부로 유입되지 않도록 전자파챔버 차폐완결성이 유지되어야 한다. 이를 정량적으로 측정함으로서 전자파챔버의 차폐율(Shielding Effectiveness)이 정의될 수 있다. 이상적으로는 전자파챔버의 차폐구조물이 이음새 없이 완벽한 차폐완결성이 유지되어야 하나, 시험품의 이동을 위한 도어 및 외부 EGSE와 시험품간 전기적인 연결을 위한 포트 플레이트의 설치로 인해 완벽한 차폐완결성을 유지하는 것은 불가능하다. 따라서, 본 논문에서는 항공우주연구원에 설치된 전자파챔버의 일반 차폐면, 도어, 포트 플레이트에 대한 차폐율 측정을 통해 차폐율을 정량적으로 검증하였다. 또한, 본 측정 경험과 결과 분석은 전자파 챔버에서 이뤄지는 전자파환경시험의 신뢰성을 증진하고 향후 전자파 챔버 유지보수 및 대형 위성의 전자파 환경시험을 위한 대형 전자파 시험시설의 성능시험을 위해 활용될 수 있을 것이다.