• 한국콘텐츠학회논문지
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• 제7권4호
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• pp.39-48
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• 2007

Ad hoc 네트워크는 고정된 기지국이나 기반네트워크가 없는 무선 네트워크이다. DUDMAC(dual -channel DMAC) 프로토콜에서, 제어 채널에서의 ORTS와 OCTS는 dearness 문제를 해결하고, 데이터 채널에서의 DDATA와 DACK는 방향성 안테나에 대한 효과적인 블로킹 알고리즘을 사용함으로써 공간 재사용을 향상시킨다. 본 논문에서는 DUDMAC 프로토콜에 전송전력을 제어하는 방식을 적용한 PCDUDMAC(power controlled DUDMAC)프로토콜을 제안한다. PCDUDMAC 프로토콜에서, 데이터 채널에서의 DATA와 DACK의 전력제어는 전송 전력 소모를 최소화하고, 공간 재사용을 증가시킨다. 제안하는 MAC 프로토콜의 성능은 퀄넷(QualNet) 버전 3.8 시뮬레이터를 사용하여 확인하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.821-824
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• 1999

In this article, as a way of pursuing high spectral efficiency and flexible cell planning, co-channel dual-polarization techniques are suggested for B-WLL applications. It provides a double down stream capacity compared with conventional scheme and also makes some flexibility in cell planning. In order to implement co-channel B-WLL system, some frequency plans, interference cancellation methods, and system block diagrams are presented here.

• The Korean Journal of Physiology and Pharmacology
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• 제2권5호
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• pp.549-553
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• 1998

Using the planar lipid bilayer method, we investigated the effect of d-tubocurarine (dTC) on the extracellular side of large-conductance $Ca^{2+}-activated\;K^+$ channel from rat brain. When the initial open probability (Po) of the channel was relatively high, dTC decreased channel activity in a concentration dependent manner. In contrast, when the initial Po was lower, sub-micro molar dTC increased channel activity by destabilizing the closed states of the channel. Further addition of dTC up to micro molar range decreased channel activity. This dual effect of dTC implicates that there exist at least two different binding sites for dTC.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.203-206
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• 2007

The Space-borne electro-optical camera system has panchromatic redundant image channel as well as primary channel in order to increase reliability of satellite system. In most case redundant channel never been used during the whole mission period. Staggered array configuration using redundant image channel and new operation mode proposed which operates primary and redundant channel simultaneously. Without new hardware design, fast electronics and system complexity, we can get 1.414 times more fine GSD image of original system or we can get 1.414 times more SNR or High dynamic range imaging mode. In this paper we deal with several image quality improvement methods using dual panchromatic channel.

• 방송공학회논문지
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• 제12권5호
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• pp.516-524
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• 2007

한정된 주파수의 효율적인 사용을 위해 디지털 동일 채널 중계기(DOCR, Digital On-Channel Repeater)를 이용하여 SFN을 구성하는 연구가 진행되고 있다. 그러나 DOCR를 사용하는 경우에 송신기의 신호와 DOCR의 출력 신호 사이의 지연 시간 때문에 선행 고스트가 필연적으로 발생한다. 기존의 결정 궤환 등화기에서는 전방 필터가 선행 고스트를 제거하는 과정에서 잡음 증가 및 유색 잡음을 발생시켜 수신 성능의 열화가 심하게 발생한다. 본 논문에서는 동일 채널 중계기를 사용한 SFN 구성시 필연적으로 발생하는 선행 고스트로 인한 수신 성능의 감소를 줄이기 위해 이중 후방필터 구조의 결정 궤환 등화기를 사용할 것을 제안하였다. 제안된 등화기의 후방필터는 결정 값을 사용하는 결정 후방필터와 등화기의 출력값을 사용하는 비결정 후방필터로 구성되어 있다. 부가적으로 사용된 비결정 후방필터 때문에 제안된 등화기는 잡음 증가와 유색 잡음이 발생하지 않아 기존의 결정 궤한 등화기에 비교하여 수신 성능 이득이 발생한다. 따라서 제안된 등화기 구조는 ATSC DTV의 동일 채널 중계기를 이용하여 SFN을 구성할 때 커버리지의 확대에 기여할 것이다.

• Transactions on Electrical and Electronic Materials
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• 제7권2호
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• pp.53-57
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• 2006

In this paper, a Symmetric Dual-gate Single-Si TFT, which includes three split floating n+ zones, is simulated. This structure drastically reduces the kink-effect and improves the on-current. This is due to the separated floating n+ zones, the transistor channel region is split into four zones with different lengths defined by a floating n+ region. This structure allows effective reduction in the kink-effect, depending on thy length of the two sub-channels. The on-current of the proposed dual-gate structure is 0.9 mA, while that of the conventional dual-gate structure is 0.5 mA, at both 12 V drain and 7 V gate voltages. This result shows an 80% enhancement in on-current. In addition, the reduction of electric field in the channel region compared to a conventional single-gate TFT and the reduction of the output conductance in the saturation region, is observed. In addition, the reduction in hole concentration, in the channel region, in order for effectively reducing the kink-effect, is also confirmed.

• 한국전기전자재료학회논문지
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• 제18권5호
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• pp.423-430
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• 2005

In this paper, we have simulated a Symmetric Dual-gate Single-Si TFT which has three split floating $n^{+}$ zones. This structure reduces the kink-effect drastically and improves the on-current. Due to the separated floating $n^{+}$ zones, the transistor channel region is split into four zones with different lengths defined by a floating $n^{+}$ region. This structure allows an effective reduction of the kink-effect depending on the length of two sub-channels. The on-current of the proposed dual-gate structure is 0.9 mA while that of the conventional dual-gate structure is 0.5 mA at a 12 V drain voltage and a 7 V gate voltage. This results show a $80 {\%}$ enhancement in on-current by adding two floating $n^{+}$ zones. Moreover we observed the reduction of electric field In the channel region compared to conventional single-gate TFT and the reduction of the output conductance in the saturation region. In addition we also confirmed the reduction of hole concentration in the channel region so that the kink-effect reduces effectively.

• 한국임상약학회지
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• 제30권4호
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• pp.259-263
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• 2020

Background: Dual-type calcium channel blockers (CCBs), such as efonidipine and cilnidipine, are renoprotective drugs that reportedly reduce proteinuria by dilating afferent and efferent arterioles of the glomerulus. However, studies comparing the effect of dual-type CCB on proteinuria have not been conducted. Therefore, we aimed to compare the effect of dual-type CCB (efonidipine and cilnidipine) usage patterns in hypertensive patients with chronic kidney disease (CKD). Methods: This single-center, retrospective study included 53 patients with CKD who 1) initiated efonidipine or cilnidipine treatment while on a renin-angiotensin system inhibitor and 2) had received efonidipine or cilnidipine for at least one year. We compared usage patterns between the efonidipine and cilnidipine groups during the one-year period and analyzed the following outcomes: urinary protein-to-creatinine ratio, blood pressure, and serum creatinine. Results: The study included 25 patients in the efonidipine group and 28 patients in the cilnidipine group. In both groups, blood pressure and urinary protein-to-creatinine ratios tended to decrease; however, the change during each interval was not significant. Conclusions: In patients with CKD who were on renin-angiotensin system inhibitor therapy, the addition of a dual-type CCB (i.e., efonidipine or cilnidipine) tended to reduce proteinuria; however, the change during each interval was not significant.

• JSTS:Journal of Semiconductor Technology and Science
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• 제9권2호
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• pp.110-116
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• 2009

The prominent advantages of Dual Material Surrounding Gate (DMSG) MOSFETs are higher speed, higher current drive, lower power consumption, enhanced short channel immunity and increased packing density, thus promising new opportunities for scaling and advanced design. In this Paper, we present Transconductance-to-drain current ratio and electric field distribution model for dual material surrounding gate (DMSGTs) MOSFETs. Transconductance-to-drain current ratio is a better criterion to access the performance of a device than the transconductance. This proposed model offers the basic designing guidance for dual material surrounding gate MOSFETs.

• 한국통신학회논문지
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• 제27권4B호
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• pp.372-378
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• 2002

본 논문에서는 Ku 대역 위성 중계기용 도파관형 협대역 채널 여파기를 설계, 제작하였으며 2단 반시형 등화기를 사용하여 대역 내에서의 군지연 및 진폭 변화를 최소화하였다. 주파수 선택도 규격을 만족시키기 위하여 채널 여파기는 8차 타원 응답형으로 설계하였으며 무게 및 부피 최소화를 위하여 여파기와 등화기 공히 원통형 공동의 TEl13 모드의 수직, 수평 편파를 이용하는 이중모드 공진기로 설계하였다. 제작한 채널 여파기와 등화기는 위성 중계기에 적용 가능한 성능을 나타내었다.