위상고정 유전체 공진형 발진기의 설계 및 제작에 관한 연구

서곤,박창현,김장구,최병하,Seo Gon,Park hang-Hyun,Kim Jang-Gu,Choi Byung-Ha 대한전자공학회 2005 電子工學會論文誌-TC (Telecommunications) Vol.42 No.3

본 논문에서는 부성저항 특성을 갖는 발진기 이론을 적용하여 직렬 궤환형 유전체 공진 발진기를 구성하고 바랙터 다이오드를 삽입하여 전압 제어 유전체 공진 발진기를 제작한 후, 샘플링 위상비교기와 루프 필터를 결합한 PLL방식을 도입하여 고안정 주파수 발생기인 위상고정 유전체 공진형 발진기를 설계 및 제작하였다. 설계 제작한 PLDRO는 주파수 12.05 GHz에서 13.54 dBm의 출력 전력을 얻었으며, 이때의 주파수 가변 동조 범위는 중심 주파수에서 약 ${\pm}7.5\;MHz$ 이며, 전력 평탄도는 0.2 dBm으로서 매우 우수한 선형 특성 결과를 얻었다. 또한 데이터 전송시 오율특성에 상당한 영향을 미치는 위상 잡음은 carrier로부터 100 KHz 떨어진 offset 지점에서 14.5 dBc/Hz을 얻었다. 고조파 특성은 2 차 고조파에서 -41.49 dBc 이하의 특성을 나타내었다. 이러한 특성은 위상고정을 하기 전의 전압 제어 발진기보다 더욱 향상된 특성을 보였으며, 종전의 PLDRO보다 위상 잡음과 전력 평탄도면에서 개선시킬 수가 있었다. In this papers, we first, therefore, designed VCO(voltage controlled oscillator) that is composed of the dielectric resonator and the varactor diode, and then designed and fabricated PLDRO(phase locked dielectric resonator oscillator) that is combined with the sampling phase detector and loop filter. The measured results of the fabricated PLDRO at 12.05 [GHz] show the output power is 13.54 [dBm], frequency tuning range approximately +/- 7.5 [MHz], and Power variation over the tuning range less than 0.2 [dB], respectively. The phase noise which effects on bits error rate in digital communication is obtained with -114.5 [dBc/Hz] at 100 [KHz] offset from carrier, and The second harmonic suppression is less than -41.49 [dBc]. These measured results are found to be more improved than those of VCO without adopting PLL, and the phase noise and power variation performance characteristics show the better performances than those of conventional PLL.

황동이 피복된 코드의 표면 상태가 배합고무와 코드의 접착에 미치는 영향

서곤,류민웅,전대진,손봉영 ( Gon Seo,Min Woong Ryoo,Dae Jin Jeon,Bong Young Sohn ) 한국공업화학회 1994 공업화학 Vol.5 No.6

80℃에서 열처리하거나, 80℃와 상대습도 85%인 습도 조건에서 처리한 황동이 피복된 강선 코드의 표면 상태와 고무와 접착 성질을 조사하였다. 열처리로 황동의 산화가 진행되었으며, 습윤처리 후에는 더 심하게 산화되었다. 처리기간이 길어질수록 전처리한 코드의 접착 성질이 나빠졌으며, 고무부착 정도가 심하게 저하되었다. 황동 피복층의 산화로 인한 코드의 접착 성질 저하를 산화아연층의 과도한 성장과 연계지어 설명하였다. Adhesion between cord and rubber compound of brass plated steel cords pretreated at 80℃ in air and at 80℃ and 85% of relative humidity was studied. Surface change of brass with pretreatment was also studied. Brass was oxidized at thermal treatment and oxidation was accelerated with water at humid treatment. Adhesion of pretreated cords decreased with treatment period. The decreasing tendency of rubber coverage was severe. Decrease in adhesion properties due to brass oxidation was discussed relating to the overgrowth of zinc oxide layer.

타이어에서 스틸코드와 배합고무의 접착(2)

서곤,Seo, Gon 대한타이어공업협회 1997 타이어 Vol.191 No.-

XPS 를 이용한 금속판과 배합고무의 접착 및 접착열화 연구

서곤,강상용,김민호 ( Gon Seo,Sang Yong Kang,Min Ho Kim ) 한국화학공학회 1991 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.29 No.1

The adhesion between metal plate(Cu, Zn, and Cu/Zn) and rubber compound, and the degradation processes were studied by using X-ray photoelectron spectroscopy. Copper sulfide layer was formed at the interface through the reaction of copper plate and sulfur in rubber compound, but copper plate didn`t adhere to rubber compound because copper sulfide layer was separated from copper plate. Zinc plate did not show good adhesion to rubber compound, because the formation rate of zinc sulfide layer at the interface was too slow. Brass plate strongly adhered to rubber compound. Excellent adhesion can be interpreted in terms of fast formation of copper sulfide layer at the interface, but excessive growth of the layer is controlled by the presence of metallic zinc. The adhesion between brass plate and rubber compound was severely deteriorated after hot water aging, and similar results were found for the adhesion of zinc plate after salt solution aging. The degradation of adhesion was also discussed in related to chemical composition and phenomenological deformation at the interface.

열화처리에 따른 고무와 강선코드간 접착계면의 변화

서곤,손봉영 ( Gon Seo,Bongyoung Sohn ) 한국공업화학회 1994 공업화학 Vol.5 No.4

열화처리 후 고무와 황동이 피복된 강선코드의 접착계면 변화를 오제 광전자 분광기와 주사 전자현미경으로 조사하였다. 열열화 후에는 접착층의 부분 산화와 추가 성장이, 습윤열화 후에는 접착층과 황동의 부분 소실이, 동적열화 후에는 접착층의 파괴와 철심의 부식이 관찰되었다. 이러한 접착제면의 변화를 인장시험에서 측정된 접착 성질과 관련지어 고찰하였다. The changes in adhesion interface between rubber compound and brass plated steel cord after various aging treatments were studied by using an Auger electron spectrometer and a scanning electron microscope. After thermal aging, partial oxidation and additional growth of adhesion layer were observed. The adhesion layer and brass were partially removed after humid aging. With dynamic aging the adhesion layer was destroyed and the corrosion of steel core was proceeded. The changes in adhesion interface were discussed in terms of the adhesion properties determined from the stress-strain experiments.

1 - 부텐 전환반응에서 HZSM - 5 제올라이트 촉매에 대한 인의 담지효과

서곤,김도철,고태석,박태진 ( Gon Seo,Dochul Kim,Tae Seog Ko,Taejin Park ) 한국화학공학회 1991 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.29 No.4

Conversion reaction of 1-butene over phosphorus-impregnated HZSM-5 zeolite was studied. The effect of phosphorus impregnation was discussed with the product distributions observed at various conditions of reaction temperature and partial pressure of 1-butene. The initial product distribution can be explained by the reaction path based on the formation of octene or dodecene from two or three molecules of 1-butene via cracking to smaller olefins. Activities for the cracking of pentenes and hexenes and for the dehydrocyclization to aromatic formation were reduced by the phosphorus impregnation. These effects were explained by the reduction of catalytic activity for cracking and dehydrocyclization of olefin.

Cu(Ⅱ) Y Zeolite에 흡착된 푸란화합물에 대한 EPR 연구

서곤,전학제,Gon Seo,Hakze Chon 대한화학회 1980 대한화학회지 Vol.24 No.6

Cu(Ⅱ) 이온이 교환된 zeolite Y에 푸란이 흡착되는 형태를 알아보기 위해, 푸란과 2-메틸푸란이 흡착될 때 나타나는 EPR 스펙트럼을 조사하였다. 푸란이 흡착되면, Cu(Ⅱ) 이온의 흡수 피이크는 감소되면서 g-factor가 2.002, 피이크폭이 8 gauss인 단일 흡수피이크가 나타난다. 메틸기가 치환된 2-메틸푸란이 Cu(15)Y에 흡착되면, 푸란고리 및 메틸기의 수소에 의한 초미세구조가 나타나며, 구리의 이온 교환도가 커지면, 초미세구조는 약해진다. 푸란이 Cu(Ⅱ) 이온이 교환된 zeolite Y에 흡착되어 나타나는 새로운 흡수피이크는 Cu(Ⅱ) 이온과 푸란고리사이에 형성된 전하이동착물에 의한 것으로 생각되었다. The EPR absorption of furan compounds adsorbed on CuY zeolite was studied. With the adsorption of furan on CuY a new high field having a width of 8 gauss and g-factor of 2.002 appeared in EPR spectrum, while the original signal of Cu(Ⅱ) decreased. When 2-methylfuran was adsorbed on Cu(15)Y a new absorption band with a hyperfine structure appeared. With the increase of the degree of Cu(Ⅱ) ion exchange the resolution of the hyperfine structure became poor. The appearance of the new band was interpreted in terms of the formation of a charge transfer complex between Cu(Ⅱ) ion and the furan ring.

ZSM -5 제올라이트의 결정화 속도에 관한 연구

서곤,정경환,박태진 ( Gon Seo,Kyeonghwan Chung,Tae Jin Park ) 한국화학공학회 1992 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.30 No.3

Crystallization process of ZSM-5 zeolite from dilute silicate-aluminate solution was studied. Crystallization curves, pH change of reactant, and size distribution of final product were examined at 150-195℃. The crystallization curve can be simulated adopting optimum rate constant for linear growth, if the crystal is growing from nuclei formed during induction period with the constant growth rate and the fraction of soluble species is constant till all amorphous reactant is dissolved. The rate constants for linear growth are determined as 0.009 ㎛·min^(-1) at 150℃, 0.038 ㎛·min^(-1) at 175℃, and 0.092 ㎛·min^(-1) at 195℃.

Pd / C 촉매상에서 하이드라진에 의한 용존산소 환원반응의 속도론

서곤,박경준,문전수,박태진 ( Gon Seo,Kyoung Jun Park,Jeon Soo Moon,Tae Jin Park ) 한국화학공학회 1996 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.34 No.5

The reduction reaction of dissolved oxygen in water by hydrazine over activated carbon-supported palladium catalyst was studied at 15-35℃. The initial concentration ratio of hydrazine to dissolved oxygen was varied within 1.5-5, and the ratio of catalyst mass to water volume within 0.025-0.2g·L^(-1). The reaction order for hydrazine could be approximated to ½ and for dissolved oxygen to 1, respectively. Activation energy was determined to he 52kJ·㏖^(-1).

타이어에서 스틸코드와 배합고무의 접착(1)

서곤,Seo, Gon 대한타이어공업협회 1997 타이어 Vol.190 No.-