• 센서학회지
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• 제30권3호
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• pp.139-147
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• 2021

Numerical analysis was performed using FIMMWAVE to optimize the specifications of Si₃N₄/SiO₂ slot and ridge-slot optical waveguides based on confinement factor and effective mode area. The optimized specifications were confirmed based on sensitivity in terms of the refractive index of the analyte. The specifications of the slot optical waveguide, i.e., the width of the slot and the width and height of the rails, were optimized to 0.2 ㎛, 0.46 ㎛, and 0.5 ㎛ respectively. When the wavelength was 1.55 ㎛ and the refractive index of the slot was 1.3, the confinement factor and effective mode area of 0.2024 and 2.04 ㎛², respectively, were obtained based on the optimized specifications. The thickness of the ridge and the refractive index of the slot were set to 0.04 ㎛ and 1.1, respectively, to optimize the ridge-slot optical waveguide, and the confinement factor and effective mode area were calculated as 0.1393 and 2.90 ㎛², respectively. When the confinement coefficient and detection degree of the two structures were compared in the range of 1 to 1.3 of the analyte index, it was observed that the confinement coefficient and sensitivity were higher in the ridge-slot optical waveguide in the region with a refractive index less than 1.133, but the reverse situation occurred in the other region. Therefore, in the implementation of the integrated optical biochemical sensor, it is possible to propose a selection criterion for the two parameters depending on the value of the refractive index of the analyte.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1997년도 제25회 춘계학술대회
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• pp.136-141
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• 1997

Rotary compressor is one of the most useful mechanism that is widely applied in refrigeration and air-conditioning systems. That is due to character of rotary compressor -compact, simple etc.While there is a lot of strong points, there is room for improvement because it is composed of many parts which have wear problem, friction losses and leakage. In this paper, theoretical investigation about vane and slot parts at which we observe severe wear is carried out. Through the study of lubrication, the behavior of vane during one cycle can be predicted and the cause of wear at slot will be discovered. To solve the equations, fletcher-powell method is applied. The result of analysis show that vane bevell to the slot part with discharge port before rotation of shaft is 180 degree and bevell to the slot part with suction port after 180 degree. The motion of vane is divided 3 mode that depends on behavior of vane. This paper define the first mode when vane tilt to the compression chamber, the second mode when vane tilt to the suction chamber, and the third mode when vane move straightway.

• 센서학회지
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• 제30권3호
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• pp.131-138
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• 2021

The optimization of the specifications of vertical silicon on insulator (SOI) slot optical waveguides suitable for integrated-optical biochemical sensors was performed through computational analysis of the confinement factor of the guided mode distributed in the slot in addition to analytical examination of the TE mode. The optimized specifications were confirmed based on sensitivity in terms of the change in the refractive index of the biochemical analyte. When the slot width, rail width, and height were set to 120 nm, 200 nm, and 320 nm, respectively, the confinement factor was evaluated to be about 56% and the sensitivity was at least 0.9 [RIU/nm].

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.419-422
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• 2007

This paper, designed UWB elliptical slot antenna and analysis based on the distribution of the electromagnetic fields pattern and resonant mode of designed antenna is presented. Designed antenna is fabricated on FR4 substrate with thickness of 1.524mm and relative dielectric constant 4.4. The measured bandwidth of $3.6GHz{\sim}20GHz$ for VSWR<2. Through the field pattern and resonant mode analysis that the slot antenna operates on a series of the multi-pole radiation based on TE modes matched to system impedance. And the perfect magnetic wall is along the axis of symmetry on the y-z plane. This result gives us an easier method to design the similar antennas, which is the impedance matching to the system impedance after once constructing a proper structure with a series of multi-mode resonances.

• 한국통신학회논문지
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• 제19권3호
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• pp.553-559
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• 1994

본 논문에서는 마이크로스트립-슬롯 결합 선로에 대한 Green함수를 스펙트럼 영역에서 유도하고, 수치적 결과를 정확히 얻기 위해 마이크로스트림 선로와 슬롯 부분에서의 전류분호에 대한 특이점을 고려한 기저함수를 이용한 Galerkin방법을 적용하여 선로의 특성 파라미터를 계산하였다. 특히, 마이크로스트림-슬롯 결합선로의 특성 중 마이크로스트립 선로에의한 우모드(even mode)와 슬롯에 의한 기모드(odd mode)의 특성에 의한 선로의 각 특성을 구하였고, 계산 결과값의 정확성을 비교하기 위해 기존의 데이터와 비교하였다.

• 전자공학회논문지A
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• 제33A권11호
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• pp.70-77
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• 1996

In this paper, a modifed TE$_{113}$/TM$_{012}$ triple-mode bandpass filter is implemented by using a modified inter-cavity iris in which the number of slots are reduced upto 50%. In a coventioanl iris two prirs of slot apertures are used to independently couple three resonant modes between two adjacent cavities. However, if transverse magnetic polarizability of a pair of veritcal slot apertures is used to control weak horizontal TE$_{h}$-TE$_{h}$ mode coupling, the width of novel iris slots would substitute for the slot length of the conventional iris, causing to eliminate the horizontal slot apertures. The measured data of two filters, which are the modified filter and ocnventional one, are compared. Experimental result shows that the characteristics of the novel triple-mode filter matches well that of the conventional filter.

• 전자공학회논문지A
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• 제33A권6호
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• pp.62-71
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• 1996

In this paper, we design tripel-mode channel filter using iris optimization technique and investigate its response. The cavity diameter is determined to resonate three orthogonal modes coincidently and inter-cavity iris is optimized in which one slot control one TE-TE mode and other TM-TM mode couplings simultaneously. Since the electric/magnectic field is variable due to slot position, the center position of the slot which handle coupling coefficients of two modes should be designe dwith optimizatin technique presented here. The implemented triple-mode filter in this paper saves its mass and volume upto 33% relating to the dual-mode filter, caused by the reduced number of cavities.

• 한국통신학회논문지
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• 제22권6호
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• pp.1251-1258
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• 1997

Generally, it is very important to study selective coupling between cavities of the filter structure using multimode cavity resonator. In this paper, we have manufactured 5-pole bandpass filter(BPF) using dual and triple-mode cavity resonator. To do so, we have derived the formulas for coupling coefficient about coupling between TE-modes from TM/TE-mode's tangential and lognitudinal field intensities each other. To implement the Chebyshev response, the intercabity slot combining dual-mode and triple-mode is designed to couple one H-field of TE-mode parallel to slot plate. In this paper, specially it is derived the formulas for T $E_{11p}$-mode from TE-modes, and determined after obtaining location and size of intercabity slot from the equation. In this ppaer, based on this result, we designed and implmented teh bandpass filter operated at the center frequency of 14.5GHz with a Chebyshev response. For the manufactured cavity filter, dual-mode and triple-mode cavity are resonted by two orthogonal T $E_{113}$-modes, and by two orthogonal T $E_{113}$-modes and one T $M_{012}$-mode, respecitively. The 2-stage 5-pole BPF proposed in this paper has the insertion loss of -2.32dB, the reflection loss of -15dB in the passband, and the out-or-rejection of -67dB.

• 한국통신학회논문지
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• 제21권2호
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• pp.495-504
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• 1996

본 논문에서는 슬롯결합 급전구조를 갖는 직렬급전 마이크로스트립 배열 안테나의 정확한 해석 및 설계방식을 제시하고 그 특성을 분석하였다. 슬롯결합 급전구조의 정확한 해석은 급전선에서의 진행파 모드와 비진행파를 모드를 모두 고려하는 full-wave방법과 안테나간의 회로적인 결합을 이용하여 해석하였다. 수치해석에 사용된 기저함수는 해의 수렴도, 정확도 및 계산시간을 비교하여 패치는 3개의 EB모드, 슬롯은 1개의 PWS모드, 급전선은 5개의 PWS모드를 사용하였다. 이러한 안테나 해석을 바탕으로 직렬급전 배열 안테나가 정재파형 구조로 설계되었다. 정재파형 구조에서 각 소자의 여기량을 조절하는 설계방식으로는 슬롯의 길이를 변화시키는 방식과 슬롯과 급전선과의 이격거리를 변화시키는 방식을 사용하였다. 본 논문에서 사용한 이론을 이용하여 8소자 Cheyshev배열 안테나를 설계하여 실험한 결과 슬롯과 급전선간의 이격거리를 조절하여 설계하는 방식이 각 소자간의 공진 주파수의 변화가 없으므로 슬롯의 길이를 가변시키는 방식보다 설계가 간편함을 알 수 있었고, 측정 결과도 우수하게 나타났다.

• ETRI Journal
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• 제30권2호
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• pp.282-289
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• 2008

We propose a new mini-slot transmission scheme for a passive optical network (PON) in which each customer can be switched either to access mode or to internetworking mode dynamically. In this paper, we present the system implementation (called LAN-PON) as well as the performance of the proposed transmission scheme to illustrate its feasibility and benefits. A mini-slot scheme can rapidly reduce the queuing delay, which increases due to the flooding of the deflected packets in a deflection scheme. We evaluate the impact of mode switching time on the bandwidth gain (throughput) and delay of local area network (LAN) traffic in the LAN-PON with a mini-slot scheme. We also analyze a theoretical delay model of the proposed scheme. The simulation results demonstrate that switching time has an impact on LAN performance, and the average packet delay of the proposed scheme is significantly improved compared to that of the deflection scheme.