• 전기학회논문지
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• 제59권7호
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• pp.1282-1288
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• 2010

This paper proposes a novel microstrip patch antenna to make impedance matching possible by using slot/T-slot capacitive coupling between the patch and 50 $\Omega$ feed line on a ground plane. The single band/linear polarization patch antenna shows linear polarization at 2.4 GHz band. Under -10 dB return loss, the single band/linear polarization patch antenna obtains 50 MHz bandwidth at 2.37 GHz~2.42 GHz. The dual band/dual polarization microstrip patch antenna shows circular polarization at 2.4 GHz band and linear polarization at 3.1 GHz band. Under -10 dB return loss, The dual band/dual polarization microstrip patch antenna obtains 340 MHz bandwidth at 2.23~2.57 GHz and 375 MHz bandwidth at 2.95~3.325 GHz.

• 한국통신학회논문지
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• 제28권3A호
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• pp.166-170
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• 2003

In this paper, the characteristics of Koch island microstrip patch antenna are investigated by numerical and experimental methods. The Koch patch is fractal shaped antenna which can be characterized by two properties such as space-filling and self-similarity. Due to its space-filling property of fractal structure, the proposed Koch fractal patch antennas are smaller in size than that of conventional square patch antenna. From numerical and experimental results, it is found that as the iteration number and iteration factor of Koch patch increase, its resonance frequency becomes lower than that of conventional patch, thus contributes to antenna size reduction. In particular, when the fractal iteration factor is 1/4, the fractal antenna is 45% smaller in size than that of conventional patch, while maintaining radiation patterns comparable to those of rectangular antenna and cross polarization level is about -20~-14 dB.

• Biomolecules & Therapeutics
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• 제4권2호
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• pp.205-207
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• 1996

Clonidine, an antihypertensive drug, stimulates postsynaptic alpha-2 adrenergic receptors in the central nervous system and lowers arterial pressure through the effects on both cardiac output and peripheral resistance. However, many patients experience that sedation and xerostomia occur upon oral administration of clonidine. These side effects are due to high plasma peak concentration and can be avoided when clonidine is given transdermally. In this study, we tested the antihypertensive effects of trandermal administration of clonidine patch on spontaneously hypertensive rat (SHR) which is a model animal for human essential hypertension. Forty eight SHR (male) were divided into six groups according to the dose levels, respectively. After transdermal administration of clonidine patch of each dose, systolic blood pressure and heart rate were measured. Clonidine patch produced maximal antihypertensive and bradycardiac effects 48 hrs after administration and antihypertensive effects showed dose-dependency. We suggest that antihypertensive effects of clonidine patch are similar to those of orally given clonidine and clonidine patch can be used instead of clonidine tablet.

• 한국멀티미디어학회논문지
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• 제24권3호
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• pp.373-381
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• 2021

In this paper, we propose a classification model based on convolutional neural network(CNN) for predicting 2-year recurrence in non-small cell lung cancer(NSCLC) patients using preoperative chest CT images. Based on the region of interest(ROI) defined as the tumor internal and external area, the input images consist of an intratumoral patch, a peritumoral patch and a peritumoral texture patch focusing on the texture information of the peritumoral patch. Each patch is trained through AlexNet pretrained on ImageNet to explore the usefulness and performance of various patches. Additionally, ensemble learning of network trained with each patch analyzes the performance of different patch combination. Compared with all results, the ensemble model with intratumoral and peritumoral patches achieved the best performance (ACC=98.28%, Sensitivity=100%, NPV=100%).

• 대한전자공학회논문지TC
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• 제43권5호
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• pp.169-175
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• 2006

본 논문에서는 GPS 수신용 안테나인 T형 슬릿을 갖는 마이크로스트립 패치 안테나를 설계 제작하였다. T형 슬릿을 삽입한 마이크로스트립 패치 안테나는 슬릿이 없는 패치 안테나 보다 낮은 주파수에서 공진한다. 이것으로부터 패치의 크기를 축소시킬 수 있다. T형 슬릿를 갖는 마이크로스트립 패치 안테나의 공진 주파수를 계산하기 위하여 패치 표면의 전류 분포로 부터 공진 주파수 공식을 유도하였다. Ensemble 6.0을 이용하여 근사식의 정확성을 검증하였다. 이렇게 구해진 공식을 이용하여 1.575GHz에서 동작하는 최적의 안테나를 설계하였으며, 그 결과 T형 슬릿을 갖는 안테나의 경우 29%까지 안테나의 크기를 감소시킬 수 있었다. 또한 슬릿을 갖는 마이크로스트립 안테나는 대역폭은 매우 좁기 때문에 협대역 특성을 개선하기 위해 구형 슬릇을 갖는 마이크로스트립 패치 안테나를 제안하였다. 제작된 T형을 갖는 마이크로스트립 패치 안테나의 공진 주파수는 1.575GHz이고 대역폭은 50MHz를 얻었다.

• 대한가정학회지
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• 제9권2호
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• pp.40-47
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• 1971

The purpose of this study was to examine the effects of several methods of the patching on the strength of the seam-texture. The main findings warranted from the present study were as follows : 1. The breaking strength was increased in proportion to the number of stitches in the case of 5 stitches per cm and 7 stitches per cm, not in the case of 9 stitches per cm where the tendency to damage the texture stitches appeared because of the excessive. 2. In comparing the effects of three methods (1. attaching a single patch, 2. attaching a single patch and seaming, 3. attaching several ply patch), no significant difference was found among these three. 3. There was a significant difference between the effects of two methods (1. attaching a single patch and stitching one edge of it on one side of the seam, 2. attaching a single patch and stitching both edges of it on the both sides of seam). In other words, the latter was found to be significantly more effective than the former. 4. In the case of unbalanced texture 9for example, single to two ply, single ply to two ply, or single to three ply), attaching a single patch to single ply and stitching both edges of it, and attaching a single patch to cover the plain-seam and stitching both edges of it, were more effective than attaching a single patch without stitching. 5. In comparing the effects of stitching both edges of the patch in 4 stitches per cm by the machine and by the hand, no significant difference was found. But these were more effective than stitching its both edges in 2 stitches per cm by hand. 6. The plain-seam stitched one edge of patch in 2 stitches per cm by machine and other by hand was significantly stronger than the plain-seam without a patch or with patch not stitched.

• 대한전자공학회논문지TC
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• 제49권6호
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• pp.48-56
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• 2012

서로 다른 유전 상수를 가지는 기판에서 반 파장 길이 공진 모드를 이용한 ILPA (Inductive Loaded Patch Antenna)와 일반적인 패치 안테나를 설계하여 방사 특성에 대하여 연구하였다. 설계한 ILPA는 일반적인 패치 안테나보다 수평 방향으로의 방사가 억제되고 전방 이득이 향상되는 특성을 가진다. 수평 방향으로의 방사가 가장 크게 억제되며 전방 이득이 가장 큰 ILPA의 방사 패치의 길이와 via 반경이 존재함을 보인다.

• International Journal of Precision Engineering and Manufacturing
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• 제2권3호
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• pp.5-10
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• 2001

Due to the development of high-strength fibers and adhesives, it is now possible to repair cracked metallic plates by bonding reinforced patches to the plate over the crack. In this study, pre-cracked aluminum 6061-T6 alloy plates repaired with bonded carbon/epoxy composite patch are applied to investigate the effect of various patch shapes on the tensile strength and the fatigue behavior of the structure. A non-patch-boned cased and 2 type-50$\times$50, 40$\times$20 mm-composite patch-bonded cases were tested to obtain fracture loads and fatigue crack growth rate. The results showed that the patch-bonded repair improves the static strength by 17% and the fatigue life by 200% compared to non-repaired case. It means that patch-boned repair is more effective in the fatigue life. It was also revealed that the patching method along crack growth direction is more efficient in cost and weight reduction. By observing the fractography, patch-bonded repair specimens demonstrated zigzag fracture patterns compared with the non-patched specimens, which shows a typical ductile fracture.

• 대한전자공학회논문지TC
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• 제47권4호
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• pp.25-30
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• 2010

새로운 메타매터리얼 구조 패치안테나는 기존 메타매터리얼 패치안테나의 이득을 개선하였다. 새로운 메타매터리얼 커버의 구조는 $9{\times}9$ 격자 중에서 중심을 기준으로 $7{\times}7$격자를 제거하는 구조로 만들었다. 또한 그 메타매터리얼 커버는 보통 기판을 사용하여 쉽게 제작이 가능하다. 패치안테나, 메타매터리얼 패치안테나, 제안된 메타매터리얼 패치안테나의 결과를 비교해 보았으며, 비교한 결과 제안된 메타매터리얼 패치안테나는 보통 메타매터리얼 패치안테나보다 약 3dB 더 좋은 결과를 보였다.

• 대한전자공학회논문지TC
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• 제46권12호
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• pp.44-51
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• 2009

핀 배열 안테나를 이용한 선형 위상 배열 안테나의 방사 특성을 일반적인 패치안테나를 이용한 선형 위상 배열 안테나와 방사 특성을 비교하였다. 핀 배열 안테나를 이용한 위상 배열 안테나는 단위 안테나간의 상호결합이 작게 발생하기 때문에 일반적인 패치안테나를 이용한 위상 배열 안테나의 성능보다 향상되었다. 핀 태열 안테나를 이용한 선형 위상 배열 안테나는 주빔의 방향에 따른 이득과 side lobe level 의 변화가 적은 우수한 방사 특성을 가진다.