이중대역 원형편파 하이브리드 슬롯/링 안테나

성영제 대한전자공학회 2023 전자공학회논문지 Vol.60 No.1

A dual-band circularly polarized (CP) hybrid antenna, realized by combining two different types of radiators—slot and ring resonators—is proposed in this paper. The first resonant frequency f1 (Model A: 1.96 GHz, Model B: 2.58 GHz) is generated by the square slot resonator in the hexagonal patch, and the second resonant frequency f2 (Model A: 3.74 GHz, Model B: 4.09 GHz) is formed by the square ring resonator. An asymmetric structure is obtained by cutting a pair of diagonal corners of the proposed antenna to produce CP characteristics at f1. CP performance at f2 is achieved by introducing a gap in the ring. The hexagonal patch with a slot works as a resonator at f1 and GND at f2. In this study, two types of antennas are designed. In the first model, the ring resonator is placed on the same layer with the feeding structure, and in the second model, the ring resonator is placed on the same layer with the hexagonal patch. Since f1 and f2 are formed by separate resonators, they can be adjusted independently. For the first model, the measured 3 dB bandwidths are 9.2% and 5.1%. On the other hand, for the second model, the measured 3 dB bandwidths are 10.4% and 7.5%.

Simple Patch Antenna with Filtering Function Using Two U-Slots

성영제 한국전자파학회 2021 Journal of Electromagnetic Engineering and Science Vol.21 No.5

In this study, two U-slots of different sizes are used to combine the filtering function with a patch antenna. The U-shaped slots are etched into the patch, and currents in the opposite direction exist around these slots. Therefore, the currents cancel each other out, and a radiation null is formed. As a result, two radiation nulls are implemented on the left and right sides of the passband. To demonstrate the novelty of the proposed concept, a filtering patch antenna with a center frequency of 3.21 GHz and a 10 dB impedance bandwidth of 19.9% is designed and fabricated. High suppression levels of 25.33 and 19.32 dB in the lower and higher stopbands, respectively, are achieved. Therefore, a sharp band skirt and good selectivity are exhibited in the boresight gain response. The two radiation nulls are located at 2.4 and 3.7 GHz and can be independently adjusted.

Oxidative elimination of cancer cells by core/shell nanoreactors producing hydrogen peroxide

성영제,( Frederik R. Wurm ),( Katharina Landfester ),조성민 한국공업화학회 2023 한국공업화학회 연구논문 초록집 Vol.2023 No.0

단순한 급전 구조를 갖는 Broadband Multimedia Wireless System(BMWS)용 슬롯 배열 안테나

성영제,이정수,오순수,문종용,최원규,표철식,최재익,김영식 한국전자파학회 2003 한국전자파학회논문지 Vol.14 No.3

본 논문에서는 BMWS(Broadband Multimedia Wireless System)용 370개 슬롯 배열 안테나를 설계 및 제작하여, 그 특성을 측정하였다. 동작 주파수(40.5 GHz~43.5 GHz)의 특성상 안테나의 급전 손실이 크기 때문에 혼과 평행판 도파관(parallel-plate waveguide)으로 이루어진 단순한 형태의 급전 구조를 제안하였다. 제안된 급전 구조는 급전상의 효율성을 높일 수 있고, 대량 생산이 가능하다는 장점이 있다. 제작된 안테나의 경우 설계 주파수 에서 이득이 25.8 dBi를 나타내었으며 H-면의 경우 부엽 레벨은 -18 dB로 억제되었고, 3$^{\circ}$의 좁은 3 ㏈ 빔폭을 나타내었다. 안테나의 비대칭적인 구조 때문에 H-면의 경우 3 ㏈ 빔폰은 17$^{\circ}$로 나타났으며 이 때 부엽 레벨은 -27 ㏈ 이하로 억제되었다. 실험을 통해 얻은 결과는 모의 실험의 결과와 잘 일치하였다. 본 논문에서 제안한 슬롯 배열 안테나를 전력 분배기로 평행하게 결합시킴으로써 안테나의 비대칭 구조를 극복하여 H-면의 넓은 3 ㏈ 빔폭을 개선시킬 수 있을 것으로 예상된다. We design and fabricate slot array antenna for BMWS(Broadband Multimedia Wireless System) applications. This paper presents a simple feed structure, which consists of two horns and a parallel-plate waveguide, because antennas operating at 40.5 GHz~43.5 GHz have considerable feeding losses. The simple feed structure has the advantages of high-efficiency and mass-production. The fabricated antenna has a gain of 25.8 dBi with a sidelobe level below -18 ㏈ and a 3 ㏈ beamwidth of approximately 3$^{\circ}$ in the E-plane. In case of H-plane, a 3 ㏈ beamwidth is 17$^{\circ}$ and a sidelobe level is suppressed to below -27 ㏈. The experimental results are in good agreement with the simulation results. The authors expect that narrow 3 ㏈ beamwidth is obtained by combining a few proposed slot array antennas in parallel.

Collagenous Fibroma (Desmoplastic Fibroblastoma) of the Finger: A Case Report

성영제,구준범 대한영상의학회 2011 대한영상의학회지 Vol.64 No.1

Collagenous fibroma is a recently described, rare, benign, soft tissue tumor that arises in the subcutaneous tissue or muscle. We report here on a case of a collagenous fibroma of the finger. A 54-year-old man was admitted to our hospital with a painless, slow-growing mass in the finger. On magnetic resonance imaging (MRI), the mass showed iso-signal intensity on the T1-weighted image, low signal intensity on the T2-weighted image and focal non-enhancing areas on the contrast-enhanced T1-weighted image. The lesion was totally removed by surgical excision and it was pathologically confirmed to collagenous fibroma.

Primitive Neuroectodermal Tumor of Mediastinum in an Adult: A Case Report

성영제,김정숙 대한영상의학회 2009 대한영상의학회지 Vol.61 No.5

A peripheral primitive neuroectodermal tumor (PNET) is a rare and aggressive malignant tumor, which most frequently occurs in children and young adults. The most well described site of origin is the chest wall. We report the case of a primitive neuroectodermal tumor in the anterior mediastinum with unusual CT findings.

A Dual Orthogonal Fed Monopole Antenna for Circular Polarization Diversity

성영제 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.3

A monopole antenna with circular polarization diversity and high isolation is proposed in this paper. The proposed antenna consists of two bent monopole antennas and a partial ground plane. Two monopole antennas are implemented on opposite planes with respect to the ground plane. The ground plane is a right-angled isosceles triangle, and the antenna is located at one end of the ground plane. Circular polarization (CP) characteristics are obtained using this structural asymmetry. In the proposed structure, the resonant frequency at S11 is controlled by the antenna length, and the null frequency at S21 (isolation) is controlled using the bending angle of the monopole and the distance between the two antennas. From the measured results, the CP operating bandwidth of the proposed antenna is 13.8% (1.76–2.02 GHz). The measured isolation is –50 dB at the resonant frequency and –20 dB within the operating bandwidth.

Clinical Outcomes of Individualized Botulinum Neurotoxin Type A Injection Techniques in Patients with Essential Blepharospasm

성영제,남상민,유혜린 대한안과학회 2015 Korean Journal of Ophthalmology Vol.29 No.2

Purpose: To assess the clinical outcomes following botulinum neurotoxin type A (BoNT-A) treatment with an individualizedinjection technique based on the types of spasms and to compare the results of the individualizedinjection technique with those of the conventional injection technique in the same patients. Methods: From November 2011 to July 2013, 77 BoNT-A injections were performed in 38 patients. Eighteenpatients were treated with conventional BoNT-A injections before 2011, and 20 patients were referred toour hospital for unsatisfactory results after a conventional injection technique. We classified the patients byspasm-dominant sites: the lateral orbital area, representing the orbital orbicularis-dominant group (ODG); theglabella, representing the corrugator-dominant group (CDG); and the ptosis, representing the palpebral partof the orbicularis-dominant group (PDG). We increased the injection dose into the spasm-dominant sites ofthe blepharospasm groups. We assessed subjective symptom scores (functional disability score, FDS) aftertreatment. Results: This study included 38 patients (26 women, 12 men; mean age, 60.6 ± 10.9 years). There were 21 patientsin the ODG, 10 patients in the CDG, and 7 patients in the PDG. Mean ages were 59.7 ± 12.6, 59.8 ± 8.5,and 66.8 ± 9.0 years, and mean BoNT-A injection dose was 38.8 ± 11.2, 38.8 ± 11.2, and 38.8 ± 10.8 U in eachgroup, respectively (p = 0.44, 0.82 Kruskal-Wallis test). Mean FDS after injection was 1.7 ± 0.7 in the ODG, 1.4± 0.8 in the CDG, and 1.2 ± 0.3 in the PDG. There were significant differences in reading and job scale amongthe three groups. In a comparison between the conventional and individualized injection techniques, there wasa significant improvement in mean FDS and in the reading scale in the PDG with the individualized injectiontechnique. The success rate was 92.1% in the conventional injection group and 94.1% in the individualizedinjection group. Conclusions: The individualized injection technique of BoNT-A according to the spasm-dominant site is aneffective and safe treatment method for essential blepharospasm patients.

낮은 삽입손실을 갖는 소형 이중모드 공진기와 스위치 기능을 가진 여파기로의 응용

성영제,김보연,이건준,김영식 한국전자파학회 2004 한국전자파학회논문지 Vol.15 No.3

본 논문에서는 마이크로스트립 공진기에 엇갈린 슬롯과 한 쌍의 spur-line을 삽입한 소형 이중모드(dual-mode)여파기를 제안하였다. 제안한 여파기는 급전선과 공진기 사이에 존재하는 급전 갭(coupling gap)을 없앰으로써 삽입손실의 특성이 향상되었다. 엇갈린 슬롯만 가진 기존의 이중모드 여파기와 비교할 때, 엇갈린 슬롯과 spur-line을 동시에 갖는 이중모드 여파기는 이중모드 특성을 나타내는 섭동의 범위가 상당히 넓기 때문에 이중 모드 여파기의 설계가 용이해졌다. 또한, 제안된 구조의 가장자리에 존재하는 spur-line에 2개의 PIN다이오드를 삽입하여 개폐기 특성을 갖는 여파기로의 응용도 가능하였다. 또한 제안한 구조는 공진기에 삽입된 슬롯과 spur-line에 의해 전기적인 길이가 길어지므로 기존의 구조에 비해 34.7 %의 크기 감소 효과를 얻을 수 있었다. In this paper, a compact dual-mode filter structure without coupling gaps is proposed. The novel design is achieved by embedding a pair of equal crossed slots and spur-lines. Without coupling gaps between feed lines and patch resonator, the new filter can provide low insertion loss. It is found that this design has wide coupling range for dual-mode operation. It means that these characteristics of the proposed filter can reduce uncertainty in fabrication. By using two PIN diodes mounted inside a pair of spur-lines, the proposed structure works as a switchable filter. Also, it has a size reduction of about 34.7 %, compared with conventional dual-mode filters.

비디오 데이터로부터 전경 및 배경 영역 분할 방법

성영제,강행봉 가톨릭대학교 자연과학연구소 2000 자연과학논문집 Vol.21 No.-

MPEG-4에서 사용되는 객체 기반 압축(object-based coding) 기법은 영상내의 특징을 이용하여 자동으로 전경(foreground) 물체를 얻어내어 객체 단위의 압축을 실현한다. 전경 물체 추출은 영상의 압축을 효율적으로 수행할 수 있게 할 뿐 아니라 영상의 개체 단위 편집을 가능하게 하고 전송이나 검색에도 적용할 수 있어 그 활용 범위가 매우 넓다. 현재 많은 곳에서 활발한 연구가 진행 중이지만 아직 인간이 생각하듯이 정확하게 전경 물체를 추출해 낼 알고리즘이 개발되지 못한 실정이다. 본 논문에서는 전경 물체를 얻기 위한 방법으로 공간상에서 컬러의 유사도를 이용한 공간 분할(spatial segmentation)을 통하여 정지 영상을 여러 개의 영역으로 분할 한 후, 시간 축 상에서 움직임이 있는 영역을 찾아서 전경과 배경을 분할하는 방법을 제안한다. 공간 분할에서는 M-RSST방법을 이용하여 계산시간을 단축하고 과분할(over-segment) 되는 것을 방지하며, 시간 분할에서는 프레임간의 차이 영상에서의 분산 값을 이용하여 움직이는 영역을 찾아내는데 이때 기준이 되는 분산의 임계 값을 F-test를 통하여 결정하여 오차를 최소화한다. The object-based coding proposed in MPEG-4 compresses each object unit. It requires the object extracting skill. But there is no good result of extraction. So we propose a good skill of object extraction, using color and motion information of moving picture. It automatically separates foreground objects and background objects from picture. This approach is useful in the picture compression and can be also used in image transmission and retrieval. Even though it is being studied elsewhere at present, algorithms that extract the foreground objects have not reached their limit of development. In this paper, we propose foreground-background separation using spatial segmentation based on color similarity and temporal segmentation for searching for the change detection mask. Spatial segmentation performs to divide each image into several regions, which have color similarity and spatial proximity. We use the M-RSST (Multi-resolution Recursive Spanning Tree) method for spatial segmentation. Using M-RSST is faster and ensures that spatial segmentation is not over-segmented. On the other hand, the temporal segmentation yields a change detection mask that indicates moving area. We can detect the region that has the motion extracted from the variances in the different images of the three adjacent images. And we use the F-test to find out the threshold of variances in the different images.