• 대한전자공학회논문지SD
• /
• 제45권8호
• /
• pp.1-10
• /
• 2008

본 논문에서는 새로운 스위칭 방식인 LFS (Local Field Switching)을 이용하여 설계한 128비트 MRAM (Magnetoresistive Random Access Memo교)에 대해 기술하였다. LFS 방식은 MTJ (Magnetic Tunnel Junction)를 직접 통과해 흐르는 전류에 의해 형성되는 국소 자기장을 이용하여 MTJ의 극성을 변환시킨다. 이 방식은 MTJ와 전류의 거리가 가깝기 때문에 작은 전류로도 충분히 큰 자기장을 형성하므로 writing current가 적어도 된다. 또한 Digit Line이 없어도 되므로 half select disturbance가 발생하지 않아 기존 MTJ를 이용한 방식에 비해 셀 선택도가 우수하다. 설계한 MRAM은 IT(트랜지스터)-1MTJ의 메모리 셀 구조를 가지며 양방향 write driver와 mid-point reference cell block, current mode sense amplifier를 사용한다. 그리고 MTJ 공정 없이 회로 동작을 확인하기 위해 LFS-MTJ cell을 CMOS emulation cell로 대체하였다. 설계한 회로를 6 metal을 사용하는 $0.18{\mu}m$ CMOS 공정으로 구현하였고 제작된 chip을 custom board 상에서 테스트하여 동작을 확인하였다.

• 전자공학회논문지A
• /
• 제33A권11호
• /
• pp.140-151
• /
• 1996

In this study, we designed the routing structure and logic block of a SRAM cell-based FPGA with symmetrical-array architecture. The designed routing structure is composed of switch matrices, routing channels and I/O blocks, and the routing channels can be subdivided into single length channels, double length channels and global length channels. The interconnection between wires is made through SRAM cell-controlled pass transistors. To reduce the signal delay in pass transistors, we proposed a scheme raising the gate-control voltage to 7V. The designed SRAM cells have built-in shift register capability, so there is no need for separate shift registers. We designed SRAM cells in the LUTs(look-up tables) to enable the wirte operations to be performed synchronously with the clock for ease of system application. Each logic block (LFU) has four 4-input LUTs, flip-flops and other gates, and the LUTs can be used a sSRAM memory. The LFU also has a dedicated carry logic, so a 4-bit adder can be implemented in one LFU. We designed our FPGA using 0.6.mu.m CMOS technology, and simulation shows proper operation of a 4 bit counter at 100MHz.

• The Korean Journal of Physiology and Pharmacology
• /
• 제3권3호
• /
• pp.305-313
• /
• 1999

To explore whether $Cl^-$ channel blockers interact with the ATP-sensitive $K^+\;(K_{ATP})$ channel, I have examined the effect of two common $Cl^-$ channel blockers on the $K_{ATP}$ channel activity in isolated rat ventricular myocytes using patch clamp techniques. In inside-out patches, 4,4'-diisothio-cyanatostilbene- 2,2'-disulfonic acid (DIDS) and niflumic acid applied to bath solution inhibited the $K_{ATP}$ channel activity in a concentration-dependent manner with $IC_{50}$ of 0.24 and 927 ${\mu}M,$ respectively. The inhibitory action of DIDS was irreversible whereas that of niflumic acid was reversible. Furthermore, DIDS-induced block was not recovered despite exposure to ATP (1 mM). In cell-attached and inside-out patches, DIDS blocked the pinacidil- or 2,4-dinitrophenol (DNP)-induced $K_{ATP}$ channel openings. In contrast, niflumic acid did not block the pinacidil-induced $K_{ATP}$ channel openings in inside-out patches, but inhibited it in cell-attached patches. DIDS and niflumic acid produced additional block in the presence of ATP and did not affect current-voltage relationship and channel kinetics. All these results indicate that DIDS among $Cl^-$ channel blockers specifically blocks the cardiac $K_{ATP}$ channel.

• 한국정보전자통신기술학회논문지
• /
• 제16권6호
• /
• pp.509-518
• /
• 2023

본 논문에서는 아날로그 회로 트리밍과 Calibration 등에 필요한 4Kb Poly-Fuse OTP IP를 설계하였다. NMOS Select 트랜지스터와 Poly-Fuse 링크로 구성된 Poly-Fuse OTP 셀의 BL 저항을 줄이기 위해 BL은 Metal 2와 Metal 3를 stack하였다. 그리고 BL 라우팅 저항을 줄이기 위해 4Kb 셀은 64행 × 32열 Sub-block 셀 어레이 2개로 나뉘었으며, BL 구동회로는 Top과 Bottom으로 나누어진 2Kb Sub-block 셀 어레이의 가운데에 위치하고 있다. 한편 본 논문에서는 1 Select 트랜지스터에 1 Poly-Fuse 링크를 사용하는 OTP 셀에 맞게 코어회로를 제안하였다. 그리고 OTP IP 개발 초기 단계에서 프로그램되지 않은 Poly-Fuse의 저항이 5kΩ까지 나올수 있는 경우까지를 고려한 데이터 센싱 회로를 제안하였다. 또한 Read 모드에서 프로그램되지 않은 Poly-Fuse 링크를 통해 흐르는 전류를 138㎂ 이하로 제한하였다. DB HiTek 90nm CMOS 공정으로 설계된 Poly-Fuse OTP 셀 사이즈는 11.43㎛ × 2.88㎛ (=32.9184㎛2)이고, 4Kb Poly-Fuse OTP IP 사이즈는 432.442㎛ × 524.6㎛ (=0.227mm²)이다.

• ETRI Journal
• /
• 제28권4호
• /
• pp.506-508
• /
• 2006

A frequency selective surface (FSS), whose unit cell consists of a ternary tree loop loaded with a modified tripole, is proposed to block multiple frequency bands. Target frequency bands correspond to Korean personal communication services, cellular mobile communication, and 2.4 GHz industrial, scientific, and medical bands. Through the adjustment of inter-element and inter-unit cell gaps, and adjustment of the length of elements, we present an FSS design method that makes the precise tuning of multiple resonance frequencies possible. Additionally, to verify the validity of our approach, simulation results obtained from a commercial software tool and experimental data are also presented.

• 한국통신학회논문지
• /
• 제25권5A호
• /
• pp.611-617
• /
• 2000

비동기 방식 W-CDMA 시스템은 동기식 방식보다 복합적인 셀 구조를 갖는 차세대 이동통신 시스템에 적합하다는 장점이 있다. 그러나, 이 경우 각 기지국마다 서로 다른 코드를 부여하기 때문에 단말기가 통화가능한 셀을 찾고 코드 동기를 이루는 데에 오랜 시간이 걸린다. 셀 획득의 지연은 통화 실패로 이어질 수 있으므로, 비동기 방식 W-CDMA 시스템을 구현하기 위해서는 고속 셀 탐색 알고리즘이 필수적인 기술이다. 본 논문에서는 도약 코드 시퀀스에 의하여 셀을 구분하고, 코드 블록 내의 이진코드이 위치를 도약코드를 사용하여 변화시킴으로써 기지국의 셀을 찾아내는 코드블럭 내의 코드 위치변조를 이용한 고속 셀 탐색 알고리즘을 제안한다. 제안된 방식은 기존의 방식에 비하여 보다 빠른 시간내에 셀을 찾을 수 있으며, 수신기도 더 간단하게 구현될 수 있다는 장점이 있다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
• /
• pp.111-111
• /
• 2012

In this talk, we represent a novel approach to investigating intra-nanorod surface plasmon coupling with control over block compositions. The multi-component rod-like nanostructures, which consist of optically active components (Au and Ag) and optically less active component (for example, Ni) in UV-vis-NIR spectral window, showed interesting optical response depending on each block length and the total length of the structure. By controlling the composition and relative lengths of the blocks that comprise these structures, we can tailor the overall optical properties. Depending on the relative fraction of Au and Ag blocks, the intensity of the transverse modes varied without noticeable peak shifts. However, the strong intraparticle surface plasmon coupling resulted in the collective appearance of longitudinal LSP modes, including higher-order modes. The experimental observations were confirmed by theoretical calculation, using a discrete dipole approximation method. In addition, we will briefly discuss how single nanorod solar cells can be synthesized by using by using electrochemical deposition and AAO hard templates.

• 대한가정학회지
• /
• 제43권4호
• /
• pp.141-159
• /
• 2005

The purpose of this study is to examine the effects of warning labels of consumption goods on consumer behavior and the consumers' evaluation in order to suggest a policy of warning labels and the Product Liability Law. The following items which are somewhat risky but are used in everyday the were selected: cup noodles, one-touch can foods, washing machine, microwave range, dry cell, hydro-oxygen detergent, baby-walker, and block-toys. Data were collected from 345 respondents by internet survey with the following results. (1) The average score of the effects of warning labels on consumer behavior was so low that warning labels are not considered effective, especially in block-toys, dry cell, and baby-walker. (2) Consumers' evaluation scores on the character size, design and sticking place of warning labels were very low. Therefore an effort to make warning labels more effective is needed.

• 한국통신학회논문지
• /
• 제8권3호
• /
• pp.83-90
• /
• 1983

N-Path SC追跡濾波器를 可聽周波數이상에서 硏究하였다. 먼저 전체 SC濾波器의 特性을 決定지우는 Filter Cell에 대한 解析으로 電荷方程式과 差等方程式에 의한 解析을 수행하고 커패시터와 스위치만으로 構成된 4-path와 8-path SC濾波器를 提示하였다. 다음 실제로 SC濾波器블록과 PLL블록의 構成으로 4-path와 8-path SC追跡濾波器를 각각 構成하였으며 最大應答의 移動, 커패시터比와 path數에 따른 Q와 利得(dB)의 變動, 追跡範圍등을 考察하였다.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제9권6호
• /
• pp.598-612
• /
• 2017

The recently developed Harmonic Polynomial Cell (HPC) method has been proved to be a promising choice for solving potential-flow Boundary Value Problem (BVP). In this paper, a flux method is proposed to consistently deal with the Neumann boundary condition of the original HPC method and enhance the accuracy. Moreover, fixed mesh algorithm with free surface immersed is developed to improve the computational efficiency. Finally, a two dimensional (2D) multi-block strategy coupling boundary-fitted mesh and fixed mesh is proposed. It limits the computational costs and preserves the accuracy. A fully nonlinear 2D numerical wave tank is developed using the improved HPC method as a verification.