• 대한전자공학회논문지SD
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• 제37권7호
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• pp.43-49
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• 2000

본 논문에서는 DDR(Double Data Rate) Synchronous DRAM에서 안전한 데이터 영역(tDV) 확보를 위한 DDL(Delay Locked Loop) 회로인 ADD(Alternate Directional Delay)회로 방식을 제안하였다. 본 방식은 디지털 DLL의 단점인 부가회로 면적(area-overhead)을 절감할 수 있는 방식으로ㅆ, 하나의 지연회로 체인(chain)을 이용하여 동시에 양방향으로 클럭을 발생할 수 있도록 함으로써 기존의 SMD(Synchronous Mirror Delay)방식에 비해 약 2배의 부가회로 면적을 감소할 수 있도록 설계하였다. 또한 설계한 ADD방식이 지터(jitter)는 50ps-140ps이고, 동ㅈ가 주파수 영역은 166MHz-66MHz이다.(205V, TYP, 동작조건)

• 한국식품영양학회지
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• 제33권3호
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• pp.309-316
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• 2020

In this study, we investigated the protective effects of Ulva lactuca methanol extracts against ultraviolet B (UVB)-induced DNA damage in HaCaT cells. First, the contents of general and antioxidative nutrient contents of Ulva lactuca were measured. The moisture, carbohydrate, crude protein, crude fat and ash were 14.01%, 44.80%, 23.19%, 3.10% and 14.90%, respectively. Magnesium that acts as DNA repair enzyme cofactor was the most abundant mineral followed by Ca, P and Fe. The total phenolic and anthocyanoside contents of Ulva lactuca were 2.69 mg/g and 0.13 mg/g, respectively. Cells treated with Ulva lactuca methanol extracts for 24 hours post UVB exposure increased cell viability in a concentration-dependent manner compared to the non-treated control. Also, Ulva lactuca methanol extracts decreased the levels of UVB-induced DNA damage such as cyclobutane pyrimidine dimer and DNA damage response (DDR) proteins such as p-p53 and p21. These results suggest that Ulva lactuca methanol extracts comprising physiological active substances such as Mg, polyphenols and anthocyanosides promote DNA repair by regulating genes related with DDR.

• 산업공학
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• 제5권1호
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• pp.3-14
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• 1992

This paper deals with the development of setup planning for Automated FIXture planning system(AFIX) which selects setups, setup sequence and operation sequence in each setup according to the machining mode. In AFIX, part type considered is prismatic workpiece that use the 3-2-1 locating system as the general structure of the fixture. The heuristic algorithms selecting setup and setup sequence are based on DDR(Degree of Dimensional Relationship), AMV(Admissible Misalignment Value) and machining sterategy and feature attributes. A case example is given to illustrate the performance fo AFIX.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2023년도 임시총회 및 춘계학술대회
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• pp.54-54
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• 2023

Nypa fruticans Wurmb (N. fruticans) is a plant that belongs to Araceae and N. fruticans is mainly found in tropical mangrove systems. The parts (leaves, stems, and roots) of N. fruticans are traditionally used for asthma, sore throat, and liver disease. N. fruticans contains flavonoids and polyphenols, which are substances that have inhibitory effects on cancer and oxidant. In previous studies, some pharmaceutical effects of N. fruticans on melanogenesis and inflammation have been reported. The present study is conducted to investigate the effect of the ethyl acetate fraction of N. fruticans (ENF) on oxidative DNA damage and UVB-induced DNA damage. DNA damage response (DDR) pathway is important in research on cancer, apoptosis, and so on. DDR pathways are considered a crucial factor affecting the alleviation of cellular damage. ENF could reduce oxidative DNA damage derived from reactive oxygen species by the Fenton reaction. Also, ENF reduced the intensity of intracellular ROS in the live cell image by DCFDA assay. UVB is known to cause skin and cellular damage, then finally contribute to causing the formation of tumors. As for the strategies of reducing DNA damage by UVB, inhibition of p53, H2AX, and Chk2 can be important indexes to protect the human body from DNA damage. As a result of confirming the protective effect of ENF for UVB damage, MMPs significantly decreased, and the expression of apoptosis-related factors tended to decrease. In conclusion, ENF can provide protective effects against double-stranded DNA break (DSB) caused by oxidative DNA damage and UVB-induced DNA damage. These results are considered to be closely related to the protective effect against radicals based on catechin, epicatechin, and isoquercitrin contained in ENF. Based on these results, it is thought that additional mechanism studies for inhibiting cell damage are needed.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.433-434
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• 2007

This paper describes a low-voltage dynamic random-access memory (DRAM) focusing on subthreshold leakage reduction during self-refresh (sleep) mode. By sharing a power switch, multiple iterative circuits such as row and column decoders have a significantly reduced subthreshold leakage current. To reduce the leakage current of complex logic gates, dual channel length scheme and input vector control method are used. Because all node voltages during the standby mode are deterministic, zigzag super-cutoff CMOS is used, allowing to Preserve internal data. MTCMOS technique Is also used in the circuits having no need to preserve internal data. Sub-1.2-V 1-Gb mobile DDR DRAM employing all these low-power techniques was designed in a 60 nm CMOS technology and achieved over 77% reduction of overall leakage current during the self-refresh mode.

• 한국정보통신학회논문지
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• 제8권6호
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• pp.1107-1114
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• 2004

시스템 패킷 인터페이스 4레벨 2단계(System Packet Interface Leve14 Phase 2)는 10Gbps 이더넷응용 뿐만 아니라, OC-192 대역폭의 ATM 및 POS를 통한 패킷 또는 셀 전송을 위한 물리계층과 링크계층 소자간의 인터페이스이다. SPI-4.2 코어는 전송 인터페이스 블록과 수신 인터페이스 블록으로 구성되어 있으며, 전이중 통신을 지원한다. 전송부는 사용자 인터페이스로부터 64비트의 데이터와 14비트의 헤더 정보를 비동기 FIFO에 쓰고, PL4 인터페이스를 통해 DDR 데이터를 전송한다. 그리고 수신부의 동작은 전송부와 역으로 동작한다. 전송부와 수신부는 캘런더 메모리를 컨피규레이션함으로서 최대 256개의 채널 지원이 가능하고, 대역폭 할당을 제어할 수 있도록 설계하였다 DIP-4 및 DIP-2 패리티 생성 및 체크를 자동적으로 수행하도록 구현하였다. 설계된 코어는 자일링스 ISE 5.li 툴을 이용하여 VHDL언어를 사용하여 기술하였으며, Model_SIM 5.6a를 이용하여 시뮬레이션 하였다. 설계된 코어는 라인당 720Mbps의 데이터 율로 동작하였다. 따라서 총 11.52Gbps의 대역폭을 지원할 수 있다. SPI-4.2 인터페이스 코어는 기가비트/테라비트 라우터, 광학 크로스바 스위치 및 SONET/SDH 기반의 전송 시스템에서 라인카드로 사용할 경우 적합할 것으로 사료된다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권1호
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• pp.20-30
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• 2001

A 1.8V $650{\;}\textrm{mm}^2$ 4Gb DRAM having $0.10{\;}\mu\textrm{m}^2$ cell size has been successfully developed using 0.11 $\mu\textrm{m}$DRAM technology. Considering manufactur-ability, we have focused on developing patterning technology using KrF lithography that makes $0.11{\;}\mu\textrm{m}$ DRAM technology possible. Furthermore, we developed novel DRAM technologies, which will have strong influence on the future DRAM integration. These are novel oxide gap-filling, W-bit line with stud contact for borderless metal contact, line-type storage node self-aligned contact (SAC), mechanically stable metal-insulator-silicon (MIS) capacitor and CVD Al process for metal inter-connections. In addition, 80 nm array transistor and sub-80 nm memory cell contact are also developed for high functional yield as well as chip performance. Many issues which large sized chip often faces are solved by novel design approaches such as skew minimizing technique, gain control pre-sensing scheme and bit line calibration scheme.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1935-1936
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• 2008

본 논문은 High speed image를 획득하기 위하여 CMOS Image Sensor를 사용한 고속카메라 구현에 관한 연구이다. Image Sensor로는 CCD Image Sensor와 CMOS Image Sensor가 있으며 CMOS Image Sensor는 CCD Image Sensor에 비해 전력소모가 적고 주변회로의 내장으로 소형화 할 수 있는 장점이 있다. 고속카메라는 충돌 테스트, 에어벡 제어 등의 자동차 분야와 골프 자세 교정 장치와 같은 스포츠 분야, 탄도 방향 측정 장비 등의 국방 분야 등 여러 분야에 많이 사용되고 있다. 본 논문에서 구현한 고속카메라 시스템은 CMOS Image Sensor를 사용하여 1280 * 1024의 해상도로 초당 약 500 frames의 영상을 획득할 수 있다. 또한 CMOS Image Sensor를 제어하고 획득한 이미지를 저장할 수 있도록 FPGA와 DDR2 메모리를 사용하고 저장된 데이터를 PC로 전송하기 위한 Camera Link 모듈 그리고 PC에서 카메라를 제어할 수 있도록 RS-422 통신기능 등으로 구성되었다.

• 산업공학
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• 제4권2호
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• pp.1-12
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• 1991

This paper deals with the development of a computer aided fixture planning system that automatically selects set-ups, set-up sequence and fixture design for prismatic parts. This study presents the hierarchical data structure for feature-based part model and the preprocessing procedure for the proposed system. The preprocessing procedure generates tools such as DDR(Degree of Dimensional Relationship), AMV(Admissible Misalignment Value) and the datum reference frame of each feature according to the proposed decision table. The proposed system is called AFIX(Automated FIXture planning system) which is implemented by using C language on the workstation. A case study for a cavity plate is presented to show the performance of the AFM.

• 한국안전학회지
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• 제15권2호
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• pp.97-102
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• 2000

This paper presents the design, construction and performance of ground treatment to support road embankment on refuse landfill. Long-term settlement of refuse landfill is analysised by Sower and Yen/scanlon. As a results of site test, predicting settlement excess the allowable settlement and ultimate bearing capacity is not satisfied. The effectiveness of DDR(Deep Dynamic Replacement) is monitered by field tests (SPT, PBT, PMT) before, during and after construction of the stone columns. The ultimate bearing capacity for reinforced landfill by stone columns obtained from the in-situ test results has been compared with the existing theories. In municipal wastes landfill, settlement after treatment using stone column is satisfied to allowable residual settlement. Therefore, long-term stability can be gain in these cases.