• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.249-255
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• 2022

Positron emission tomography for small animals has very high spatial resolution for imaging very small organs. To achieve good spatial resolution, the system must be constructed using very small scintillation pixels. When a detector is constructed using very small scintillation pixels, the size of the applicable array varies depending on the photosensor pixel. In a previous study, a study was conducted to find the maximum scintillation pixel arrangement according to the size of the photosensor. In this study, a detector with a light guide was designed to configure the detector using a more extended array of scintillation pixels, and try to find the maximum arrangement in which all scintillation pixels are imaged. The detector was designed using DETECT2000, which can simulate a detector made of a scintillator. Simulations were performed by configuring the detectors from an 11 × 11 scintillation pixel array to a 16 × 16 array. After obtaining a flood image by collecting the light generated from the scintillation pixel with a photosensor, the largest arrangement without overlap was found through image analysis. As a result, the largest arrangement in which all scintillation pixels could be distinguished without overlapping was a 15 × 15 arrangement.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.9
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• pp.1005-1014
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• 2007

In this paper, The four types SRA(Sequential Rotated Array) antennas has been analyzed. Those are consisted of a 4-elements SRA, a 8-elements SRA, the $2{\times}2$ planer array SRA and the triple (4+8+4)-elements SRA. These LHCP SRA antennas are used a probe feeding multi-layer truncated microstrip antenna whose center frequency is 11.85 CHz. The cooperated feeding circuits are designed for feeding to each elements with equal amplitude and regular phase. Comparing with the each simulation results and experiment results of this 4-type SRA antennas, the triple (4+8+4)-elements SRA showed the most electrical characteristics in the degree of integration, high gain and low cross polarization.

• Annual Conference of KIPS
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• 2016.10a
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• pp.404-405
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• 2016

본 논문은 자율주행로봇의 평면 공간 주행과 평면 공간상의 Map 정보를 생성하는 것에 관한 것이다. 자율주행 로봇은 Raspberry Pi, Sonar Sensor, Gyro Sensor를 사용해 궤적 이동에 대한 정보를 수집한다. 자율주행로봇은 정확한 직진 주행 및 회전 이동을 위해 개선된 모터 제어 기법인 PID Controller를 사용한다. 정확한 Map 정보를 생성하기 위해서 System은 주행 중에 수집한 궤도의 정보를 2차원 배열과 LIFO 자료 구조에 기록하여 Map Information을 생성해 나간다.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.219-220
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• 2009

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.10a
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• pp.255-257
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• 1987

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.261-262
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• 2007

• Journal of the Korea Computer Industry Society
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• v.8 no.1
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• pp.57-64
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• 2007

In the paper, considers the design of a detection system, consisting of n identical detectors, to process the sum of spatially invariant signal fields $S_\jmath(t)$, an additive, homogeneous, spatially isotropic (in the array plane x). covariance_separable, and zero_mean Gaussian random noise field n(t, x). consisting of arrey receivers for use in optical communication through optimum turbulence atmosphers and covriance_circuit, staistical analysis through detection the maximum gain are compared with analysis theoretical analysis theoretical value and get through experimental measured value, as well the measured valus are confirmed to agreement joint Gaussian theoretical curves.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.535-538
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• 2004

마이크로폰을 이용하여 평면상에 직교형으로 배열된 음인 도래 방향 탐지 시스템을 구성하고, A/D 변환에 있어 일반저인 샘플링 기법과 spilt-beam형 어군 탐지 시스템에 적용된 4분 샘플링 기법을 이용하여 공기중에서의 음원의 토래 방향 탐지 성능에 관한 실험을 수행하였다. 일반 실내에서 단일 주파수의 음원에 대하여 직교형 마이크로폰 배열을 사용한 음인 토래 방향 탐지 시스템 및 4분 샘플링 기법의 적용이 유용함을 확인하였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.10
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• pp.1060-1070
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• 2003

The frequency selective surface for use in Ka/Ku band parabolic antenna of domestic satellite communications is proposed. The frequency selective surface structure consists of the infinite periodic arrays of the triple square loop slot element with narrow width on the honeycomb structure of multi-layered dielectric. The frequency selective surface is fabricated and measured. The good agreement is obtained between theory and experiment. It is demonstrated that the frequency selective surface passes 14/12 GHz band wave while reflecting 30/20 GHz band wave as required.

• The Journal of the Acoustical Society of Korea
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• v.39 no.3
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• pp.170-178
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• 2020

Cymbal transducers are often used as an array rather than single because they have a high quality factor and low energy conversion efficiency. When used as an array, there occurs a big change in the frequency characteristics of the array due to the interaction between constituent transducers. In this study, we designed the structure of a cymbal transducer array to have ultra-wideband characteristics using this property. First, cymbal transducers with specific center frequencies were designed. Then, a 2×2 planar array was constructed with the designed transducers, where the cymbal transducers were arranged to have same or opposite polarization directions. For this structure, we analyzed the effect of the difference in the center frequency of and the spacing between the constituent transducers on the acoustical characteristics of the array. Based on the analysis, we designed the structure of the cymbal transducer array to have the widest possible bandwidth.