• 한국인터넷방송통신학회논문지
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• 제16권2호
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• pp.145-150
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• 2016

본 논문은 갭 슬리브 모노폴 구조를 갖는 DTV 실내 수신용 안테나를 제안하였다. 제안한 안테나는 슬리브 모노폴 기본 구조와 갭 슬리브를 이용하였다. 안테나를 최적화 하기위해 복사기와 슬리브 사이 갭 조정, 슬리브와 그라 운드 사이 갭을 조정하였다. 안테나 파라미터 특성을 확인하기 위해 ANSYS사의 HFSS를 이용하였다. 안테나 제작을 위해 비유전율이 4.7인 FR4 유전체 기판을 사용하였다. 안테나의 크기는 $213{\times}40{\times}1.6mm$이다. 제작된 안테나의 주파 수대역은 432MHz~827MHz이고, 대역폭은 395MHz이다. 최대 안테나 이득은 2.19dBi이다. 시뮬레이션과 측정 데이터 를 비교분석한 결과 간격 슬리브 구조를 갖는 DTV 실내 수신용 안테나의 실용화 가능성을 확인할 수 있었다.

• Structural Engineering and Mechanics
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• 제66권6호
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• pp.783-792
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• 2018

This paper presents a detailed theoretical study of the sleeved compression members based on a mechanical model. In the mechanical model, the core protrusion above sleeve and the contact force between the core and sleeve are specially taken into account. Via the theoretical analyses, load-displacement relationships of the sleeved compression members are obtained and verified by the experimental results. On the basis of the core moment distribution changing with the increase of the applied axial load, failure mechanism of the sleeved compression members is assumed and proved to be consistent with the experimental results in terms of the failure modes and the ultimate bearing capacities. A parametric study is conducted to quantify how essential factors including the core protrusion length above sleeve, stiffness ratio of the core to sleeve, core slenderness ratio and gap between the core and sleeve affect the mechanical behaviors of the sleeved compression members, and it is concluded that the constrained effect of the sleeve is overestimated neglecting the core protrusion; the improvement of ultimate bearing capacity for the sleeved compression member is considered to be decreasing with the decrease of the core slenderness ratio and for the sleeved compression member with core of small slenderness ratio, small gap and small stiffness ratio are preferred to obtain larger ultimate bearing capacity and stiffness.

• 한국항공우주학회지
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• 제46권6호
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• pp.487-495
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• 2018

환형 갭과 핀틀갭의 면적을 동시에 제어할 수 있는 가변 슬리브 인젝터의 분무특성을 실험적으로 분석하고, 넓은 추력범위에서 일정한 성능으로 제어할 수 있는 방안을 연구하였다. 슬리브의 개도에 관계없이 일정한 차압을 설정한 경우 설계유량을 만족하지 못하는 것을 확인하였다. 이를 개선하기 위해 개도에 따라 환형 갭과 핀틀 갭에서의 차압을 개도에 따라 다르게 적용하였다. 운용범위 내에서 설계 유량을 만족하였고, 선형적인 슬리브 면적으로 25%에서 100%까지 선형적으로 추력제어가 가능한 것을 확인하였다.

• 한국지역사회생활과학회지
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• 제24권4호
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• pp.457-469
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• 2013

The purpose of this study is to quantitatively analyze the impacts of the distribution of easing contraction of the sleeve on the external appearance of bodice and sleeve through virtual clothing simulation. Virtual clothing is conducted by differentiating the sleeve easing in accordance with the experimental condition of bodice and sleeve that are followed by draping. And then the evaluation is carried out. As a result of an analysis of the similarity between the virtual garment and the actual clothing, the whole external appearance of the bodice and sleeve was expressed similarly. The external appearance according to the distribution of easing contraction got better as the easing contraction of sleeve was concentrated on sleeve cap in front while the appearance was better at the back as it was more gently distributed than in the front. In a comparison of armhole form, the clothing of which the top of it was most similar to S0 was S4 in which the gap between the armhole and the arm was the least and the front and rear silhouette fell relatively well. In a comparison between the position of bust circumference line and that of the sleeve base line, the front of the sleeve matched the bust circumference line as the easing contraction was distributed close to the center of the sleeve cap while in the back, the sleeve base line and the bust circumference line matched when some easing contraction ratio was added close to the armpit point. The cross section figures of garment space of the shoulder, the margin was evenly distributed in S4 or S5 with differing distributions of easing contraction in the front and the back. This study is significant in that it supplies the objective baseline data which makes a novice more able to make a good external appearance of the sleeve.

• 한국인터넷방송통신학회논문지
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• 제20권5호
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• pp.135-141
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• 2020

본 논문은 다양하게 적용 가능한 슬리브 구조를 갖는 모노폴 안테나 자료를 정리한 것이다. 슬리브 모노폴 안테나는 광대역 특성을 갖고 다주파수용으로 사용된다. 슬리브 모노폴 안테나는 복사기(radiator)인 수직 도체부분과 동축 케이블과 같은 구조를 갖는 슬리브(sleeve)로 구성되어져 있다. 슬리브는 복사기와 개방 스터브 동작을 한다. 슬리브 길이는 안테나 전체 길이의 1/3~2/3로 되어야 한다. 슬리브 구조를 갖는 모노폴 안테나는 차량용 와이퍼 안테나에 적용 가능하다. 더불어, 로딩 코일을 이용한 광대역 슬리브 안테나, ISM 밴드용 광대역 프린티드 슬리브 모노폴 안테나, 갭 슬리브와 이중 슬리브, 하프 커팅을 이용한 UWB 평면형 모노폴 안테나에 적용한 사례를 구조와 광대역 측면에서 정리 분석하였다.

• Journal of Magnetics
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• 제21권3호
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• pp.405-412
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• 2016

In general, surface mounted PM synchronous motors (SPMSMs) are mainly adopted as a driving motor for high-speed applications, because they have high efficiency and high power density. However, the SPMSMs have some weak points such as the increase of magnetic reluctance and additional losses as a consequence of using a non-magnetic sleeve. Especially, the magneto-motive force (MMF) in the air-gap of the SPMSMs is weakened due to the magnetically increased resistance. For that reason, a large amount of PM is consumed to meet the required MMF. Nevertheless, it cannot help using the sleeve in order to maintain the mechanical integrity of a rotor assembly in high-speed rotation. Thus, in this paper, a multi-layer interior PM synchronous motor (IPMSM) not using the sleeve is presented and designed as an alternative of a SPMSM. Both motors are evaluated by test results based on a variety of characteristics required for an air blower system of a fuel cell electric vehicle.

• 한국인터넷방송통신학회논문지
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• 제16권1호
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• pp.215-220
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• 2016

본 논문에서는 직사각형 평면 모노폴 구조에 이중 슬리브를 추가하여 광대역화를 이룬 안테나를 제안하였다. 제안된 안테나의 임피던스 매칭을 위해 두 개의 갭 슬리브와 외각 슬리브를 추가하여 이중 슬리브 구조로 안테나 성능을 개선하였다. 안테나 파라미터 특성을 확인하기 위하여 ANSYS사의 HFSS 시뮬레이터를 이용하였다. 제안한 안테나에서 VSWR이 2 이하인 시뮬레이션 주파수 대역은 2.5GHz~10.5GHz이다. 주파수 대역폭은 8GHz이다. 실제로 제작한 안테나의 주파수 대역은 2.92GHz~10.32GHz이며, 주파수 대역폭은 7.4GHz이다. 측정된 복사패턴 주파수는 3GHz, 6GHz, 9GHz이다. 모든 주파수에서 다이폴안테나 패턴과 유사한 결과를 얻을 수 있었다. 안테나 크기는 $40{\times}40mm^2$이다. 시뮬레이션 결과와 측정 데이터를 비교분석한 결과 초광대역 평면 모노폴 안테나의 실용화 가능성을 확인할 수 있었다.

• 한국인터넷방송통신학회논문지
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• 제17권2호
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• pp.257-262
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• 2017

본 논문에서는 이중 슬리브를 갖는 직사각형 평면 모노폴 안테나에 하프 커팅과 불연속 급전 구조를 적용하여 안테나 특성을 확인하였다. 이중 슬리브를 갖는 직사각형 평면 모노폴 안테나를 자기 대칭 라인을 중심으로 하프커팅을 하고, 급전부에 불연속 구조를 적용과 이중 슬리브 간격을 조정하여 임피던스 매칭을 하였다. 안테나 파라미터 특성을 확인하기 위하여 ANSYS사의 HFSS 시뮬레이터를 이용하였고, 안테나 크기는 $21{\times}40mm^2$이다. 제안한 안테나에서 VSWR이 2 이하인 시뮬레이션 주파수 대역은 2.6GHz~10.25GHz이다. 주파수 대역폭은 7.65GHz이다. 실제로 제작한 안테나의 주파수 대역은 3.3GHz~9.75GHz이며, 주파수 대역폭은 6.45GHz이다. 측정된 복사패턴 주파수는 3.5GHz, 5.5GHz, 7.5GHz, 9.5GHz이다. 모든 주파수에서 다이폴안테나 패턴과 유사한 복사패턴 결과를 얻을 수 있었다.

• Computers and Concrete
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• 제12권2호
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• pp.131-149
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• 2013

Various types of reinforcement splicing methods have been developed and implemented in reinforced concrete construction projects for achieving the continuity of reinforcements. Due to the complicated reinforcement arrangements and the difficulties in securing bar spacing, the traditional lap splicing method, which has been widely used in reinforced concrete constructions, often shows low constructability and difficulties in quality control. Also, lap spliced regions are likely to be over-reinforced, which may not be desirable in seismic design. On the other hand, mechanical splicing methods can offer simple and clear arrangements of reinforcement. In order to utilize the couplers for the ribbed-deformed bars, however, additional screw processing at the ends of reinforcing bars is typically required, which often lead to performance degradations of reinforced concrete members due to the lack of workmanship in screw processing or in adjusting the length of reinforcing bars. On the contrary, the use of screw-ribbed reinforcements can easily solve these issues on the mechanical splicing methods, because it does not require the screw process on the bar. In this study, the mechanical coupler suitable for the screw-ribbed reinforcements has been developed, in which any gap between the reinforcements and sleeve device can be removed by grouting high-flow inorganic mortar. This study presents the uniaxial tension tests on the screw-ribbed reinforcement with the mechanical sleeve devices and the cyclic loading tests on RC columns with the developed coupler. The test results show that the mechanical sleeve connection developed in this study has an excellent splicing performance, and that it is applicable to reinforced concrete columns with a proper confinement by hoop reinforcement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2020-2022
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• 2000

The cross-linked polyethylene(herein after XLPE) insulated power cable emit the methane($CH_4$)gas in the course of chemical cross-linking process. The general stranded conductor easily discharge this methane gas through the gap of each stranded wires. But the special stranded conductor that filled with semi-conducting rubber compound to prevent water penetration which is applied to water proof type of cable(22.9kV CN/CV-W), disturb the methane gas emission. The pre-mold type cable joint shall be expanded gradually by emit of gas left in XLPE insulation. For example, sometimes the corona problem outbreak on a new power distribution line, resulted from the gap between the sleeve and semi-conductive layer of cable joint. If above mentioned problem especially happened on the way of operating. We have to shut down the line and try to discharge the methane gas in cable joint. In this point, we would like to explain the mechanism of methane gas & cable joint and our test result briefly. At last, we are pleased to introduce the solution for preventing reoccurrence of this problem.