• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.300-303
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• 1987

A microwave plasma generating system has been designed to study the properties of plasma. A microwave(2.45GHz) generated by the magnetron is transmitted to the cylindrical cavity through the the rectangular wave guide to generate hydrogen plasma. The electron temperature and the plasma density are measured by the Double Langmuir probe. A dilectric such as alumina is heated by the microwave add plasma. The surface temperature varies with the neutral gas pressure.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.52-60
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• 1997

Hornbeam trees(Carpinus laxiflora BL.) are growing in Korea and have good characteristics such as relatively high density, fine texture, split- resistance, and white colour. However, they have seldom been used as manufacturing materials This study was carried out to evaluate the possibility of using hornbeam wood as bent, wood furniture materials. Softening methods were steaming and micro-wave heating. The specimens of $15{\times}15{\times}350mm$ were used green or air-dried, and were steamed at $100^{\circ}C$ for 20min, or microwave heat ed f or 60 seconds. The bending processing conditions are showed in Table 3. The minimum solid-bending radii of air-dried wood were 40mm for steaming and 200mm for micro-wave heating, respectively. And that of green wood were 40mm for micro-wave heating. In conclusion, both of the steamed wood and micro-wave heated green wood showed very good solid bending processing properties, but micro-wave heated air-dried wood were not sufficient for bent-wood furniture.

• Journal of the Korean Wood Science and Technology
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• 제11권2호
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• pp.52-60
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• 1983

Hornbeam trees(Carpinus laxiflora BL.) are growing in Korea and have good characteristics such as relatively high density, fine texture, split-resistance, and white colour. However, they have seldom been used as manufacturing materials This study was carried out to evaluate the possibility of using hornbeam wood as bent-wood furniture materials. Softening methods were steaming and micro-wave heating. The specimens of $15{\times}15{\times}350mm$ were used green or air-dried, and were steamed at $100^{\circ}C$ for 20min, or microwave heated for 60 seconds. The bending processing conditions are showed in Table 3. The minimum solid-bending radii of air-dried wood were 40mm for steaming and 200mm for micro-wave heating, respectively. And that of green wood were 40mm for micro-wave heating. In conclusion, both of the steamed wood and micro-wave heated green wood showed very good solid bending processing properties, but micro-wave heated air-dried wood were not sufficient for bent-wood furniture.

• Journal of Biosystems Engineering
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• 제34권5호
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• pp.371-376
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• 2009

Microwave digestion is a preferred pretreatment method for agricultural samples because of its quick chemical reaction and minimum loss of analytes. In this research, a feedback temperature controller was developed to control the temperature inside a vessel for the microwave-assisted digestion system. An existing industrial microwave oven was fitted with the temperature controller for controlling inside temperature of the vessel. Four control methods, On/Off, proportional (P), proportional integral (PI), and proportional integral derivative (PID) were used and compared. Experimental results showed that PID control produced best temperature control performance. The PID controller could maintain the temperature of water sample and rice sample in the digestion system with error range of $-2.5{\sim}3.3^{\circ}C$ and $-1.9{\sim}0.5^{\circ}C$ at set temperature of $170^{\circ}C$, respectively.

• 한국세라믹학회지
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• 제47권2호
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• pp.163-168
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• 2010

Effects of compositions on the microwave dielectric properties of the MgO-$TiO_2$ system were investigated as a function of the molar ratio of MgO to $TiO_2$ ($0.9{\leq}MgO/TiO_2\;(x){\leq}1.2$). With the compositional changes, secondary phases of $MgTi_2O_5$ and $Mg_2TiO_4$ were also detected along with $MgTiO_3$. Microwave dielectric properties of the specimens were dependent on the types of phases developed in the sintered specimens. A single phase of $MgTiO_3$ showed a dielectric constant (K) of 18.2, a quality factor (Qf) of 198,000 GHz, and a temperature coefficient of resonant frequency (TCF) of $-51\;ppm/^{\circ}C$. However, the dielectric properties of the specimens with a secondary phase of $MgTi_2O_5$ (K=19.9, Qf=48,000 GHz) and/or $Mg_2TiO_4$ (K=15.6, Qf=56,000 GHz) were worsened. Dependence of the microwave dielectric properties on the secondary phase of the MgO-$TiO_2$ system was also discussed in terms of dielectric mixing rules.

• 한국ITS학회 논문지
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• 제12권5호
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• pp.46-51
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• 2013

본 논문에서는 RF 에너지 충전 시스템 기능이 가능한 이중대역 RFID 태그 안테나(Tag antenna)를 제안한다. 제안된 안테나는 UHF 대역과 Microwave 대역에서 각각 수동형과 능동형의 RFID 태그 안테나로 동작을 한다. 또한 능동형으로 동작하는 Microwave 대역 RFID 태그의 제한된 배터리 용량을 보충하기 위하여 수동형 태그로 동작하는 UHF 대역의 RFID 태그를 위한 RF 신호를 충전 회로에 적용 가능한 이중대역 RFID 태그 안테나의 특징을 가진다. 제안된 안테나는 UHF 대역 (917~923.5 MHz)과 Microwave 대역 (2.4~2.45 GHz)에서 동작을 위한 $50{\Omega}$의 단일급전이 이용된 다이폴(Dipole) 구조와 미앤더(Meander) 기생 소자들을 이용한 ${\lambda}/2$ 다이폴과 $1{\lambda}$ 다이폴로 각각 동작하는 이중대역 안테나의 특징을 가진다. 다이폴 구조는 Microwave 대역에서 동작을 하며, 다이폴 구조에 추가된 미앤더 기생 소자와 함께 UHF 대역에서 동작을 한다. 즉, Microwave 대역에 대하여 동작하는 다이폴 구조는 UHF 대역에서 동작을 위한 기생 소자들의 간접급전의 역할을 한다. 제작된 안테나는 UHF 대역의 917~923.5 MHz와 Microwave 대역의 2.4~2.45 GHz의 대역에 대하여 VSWR 2:1 이하를 만족하며, 또한 전방향적인 방사패턴 (Omni-directional radiation pattern)을 가진다. 안테나의 효율은 UHF 대역에서 45 % 이상, Microwave 대역에서 70 % 이상이며, 각각의 대역에서 0.18 dBi, 2.8 dBi 이상의 최대 이득을 가진다.

• 농업과학연구
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• 제26권1호
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• pp.50-57
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• 1999

본 시험은 L. monocytogenes KCTC 3443을 액체 배양한 후, 일반적인 열처리 및 마이크로파를 조사함으로써 가열효과에 의한 균의 불활성효과를 파악하는데 그 목적을 두었다. 2,450MHz, microwave oven을 통한 마이크로파의 온도 제어는 시료가 각각의 시험 설정 온도에 도달한 후 30분간 온도를 유지할 수 있도록 컴퓨터에 의해 제어되었으며, 온도의 편차는 ${\pm}1^{\circ}C$ 정도로 비교적 안정된 제어 효과를 보여주었다. 마이크로파 조사와 일반 가열처리 간의 균의 불활성효과를 비교한 시험에서는 55, 65, $75^{\circ}C$ 및 $85^{\circ}C$의 제어온도에서 거의 유사한 불활성도를 보여주었으며 이와같은 결과로 미루어 L. monocytogenes KCTC3443의 경우, 마이크로파 조사에 의한 비가 열 효과는 없는 것으로 보여진다. 아울러 공시균주인 L. monocytogenes KCTC3443는 $85^{\circ}C$의 30분간 가열에서도 약 $10^2{\sim}10^3cells/ml$의 균체가 생존하는 것으로 나타나 식품의 조리나 가열 후에도 2차 오염의 위험이 있는 병원성 균주로 주위가 요구된다.

• 한국세라믹학회지
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• 제34권9호
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• pp.935-940
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• 1997

This study investigated the crystallization behavior in PbO-ZnO-B2O3-TiO2 system sealing glass, inorganic polymer heat-treated by conventional heat and microwave energy. After determining heat-treated temperature for crystallization and characteristic points by DTA analysis, samples were heat-treated in a classical electric furnace and a home-style microwave oven (LG Electronic Co., 2.45 GHz, 700 W). A microwave heat-treated sample had the growth of PbTiO3 crystal at 45$0^{\circ}C$, 2$0^{\circ}C$ lower than that of a conventionally heat-treated sample. Also, it had crystallinity about 20% higher than the conventionally heat-treated sample. At 49$0^{\circ}C$, the size of PbTiO3 crystal in the conventionally heat-treated sample was larger than that in the microwave heat-treated sample due to longer heat-treated time.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.471-474
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• 2008

The pyrolytic behavior of waste tire under microwave heating was investigated. Experiments were conducted using a lab- and bench-scale system to delineate the effects of microwave output power on the response. As the results of experiments, it was found that as the microwave output power was increased between 0.84 and 3.04 kW/kg, the oil yield and required time rapidly increased and decreased, respectively. With further increase of the microwave output power, the oil yield and required time did not change significantly.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1012-1014
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• 2003

Since it's establishment Malaysian Center for Remote Sensing (MACRES) has focused on the measurements from airborne and space borne remote sensors. In the year 1999 MACRES in collaboration with Multimedia University Malaysia (MMU) began developing it's own remote sensing sensors to meet Malaysian Remote Sensing needs. MACRES adopted a very systematic approached to the development of these microwave sensors. Starting from non-imaging ground base microwave remote sensing sensors MACRES is now well into developing it's first Airborne Synthetic Aperture Radar. With the capability of developing it's own sensors MACRES will profit more on the microwave remote sensing application research. This paper will demonstrate MACRES capability in developing Microwave Remote Sensing Sensors to meet Malaysian remote sensing society needs.