• JSTS:Journal of Semiconductor Technology and Science
• /
• 제9권1호
• /
• pp.37-50
• /
• 2009

Evaluation results about area scaling capabilities of various SRAM margin-assist techniques for random $V_T$ variability issues are described. Various efforts to address these issues by not only the cell topology changes from 6T to 8T and 10T but also incorporating multiple voltage-supply for the cell terminal biasing and timing sequence controls of read and write are comprehensively compared in light of an impact on the required area overhead for each design solution given by ever increasing $V_T$ variation (${\sigma}_{VT}$). Two different scenarios which hinge upon the EOT (Effective Oxide Thickness) scaling trend of being pessimistic and optimistic, are assumed to compare the area scaling trends among various SRAM solutions for 32 nm process node and beyond. As a result, it has been shown that 6T SRAM will be allowed long reign even in 15 nm node if ${\sigma}_{VT}$ can be suppressed to < 70 mV thanks to EOT scaling for LSTP (Low Standby Power) process.

• Earthquakes and Structures
• /
• 제5권2호
• /
• pp.129-142
• /
• 2013

Linear and nonlinear time history analyses have been becoming more common in seismic analysis and design of structures with advances in computer technology and earthquake engineering. One of the most important issues for such analyses is the selection of appropriate acceleration time histories and matching these histories to a code design acceleration spectrum. In literature, there are three sources of acceleration time histories: artificial records, synthetic records obtained from seismological models and accelerograms recorded in real earthquakes. Because of the increase of the number of strong ground motion database, using and scaling real earthquake records for seismic analysis has been becoming one of the most popular research issues in earthquake engineering. In general, two methods are used for scaling actual earthquake records: scaling in time domain and frequency domain. The objective of this study is twofold: the first is to discuss and summarize basic methodologies and criteria for selecting and scaling ground motion time histories. The second is to analyze scaling results of time domain method according to ASCE 7-05 and Eurocode 8 (1998-1:2004) criteria. Differences between time domain method and frequency domain method are mentioned briefly. The time domain scaling procedure is utilized to scale the available real records obtained from near fault motions and far fault motions to match the proposed elastic design acceleration spectrum given in the Eurocode 8. Why the time domain method is preferred in this study is stated. The best fitted ground motion time histories are selected and these histories are analyzed according to Eurocode 8 (1998-1:2004) and ASCE 7-05 criteria. Also, characteristics of both near fault ground motions and far fault ground motions are presented by the help of figures. Hence, we can compare the effects of near fault ground motions on structures with far fault ground motions' effects.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2002년도 춘계종합학술대회
• /
• pp.275-278
• /
• 2002

MOSFET의 게이트 길이가 50nm이하로 작아지면 소자를 설계함에 있어 고려해야 하는 많은 문제점들이 존재하게 된다. 본 논문에서는 MOSFET 소자에 대한 문턱 전압 특성을 조사하였다. 소자에 대한 스케일링은 generalized scaling을 사용하였고 게이트 길이 100nm에서 30nm까지 시뮬레이션 하였다. 이때 나노 구조 MOSFET에 대한 스케일링의 한계를 볼 수 있었다. 문턱 전압을 구하는 방법으로는 선형 추출 방법을 사용하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권2호
• /
• pp.790-809
• /
• 2019

The design of an efficient scaler to enhance the edge data is one of the most important issues in video signal applications, because the perceptual quality of the processed image is sensitively affected by the degradation of edge data. Various conventional scaling schemes have been proposed to enhance the edge data. In this paper, we propose an efficient scaling algorithm for this purpose. The proposed method is based on the discrete cosine transform-based interpolation filter (DCT-IF) because it outperforms other scaling algorithms in various configurations. The proposed DCT-IF incorporates weighting parameters that are optimized for training data. Simulation results show that the quality of the resized image produced by the proposed DCT-IF is much higher than that of those produced by the conventional schemes, although the proposed DCT-IF is more complex than other conventional scaling algorithms.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제4권1호
• /
• pp.1-11
• /
• 2004

A FinFET, a novel double-gate device structure is capable of scaling well into the nanoelectronics regime. High-performance CMOS FinFETs , fully depleted silicon-on-insulator (FDSOI) devices have been demonstrated down to 15 nm gate length and are relatively simple to fabricate, which can be scaled to gate length below 10 nm. In this paper, some of the key elements of these technologies are described including sub-lithographic pattering technology, raised source/drain for low series resistance, gate work-function engineering for threshold voltage adjustment as well as metal gate technology, channel roughness on carrier mobility, crystal orientation effect, reliability issues, process variation effects, and device scaling limit.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제1권2호
• /
• pp.103-110
• /
• 2001

Gate oxide scaling for sub-l00nm CMOS devices has been studied. Issues on the gate oxide scaling are reviewed, which are boron penetration, reliability, and direct tunneling leakage currents. Reliability of Sub-2.0nm oxides and the device performance degradation due to boron penetration are investigated. Especially, the effect of gate leakage currents on the transistor characteristics is studied. As a result, it is proposed that thinner oxides than previous expectations may be usable as scaling proceeds. Based on the gate oxide thickness optimization process we have established, high performance CMOS transistors of $L_{gate}=70nm$ and $T_{ox}=1.4nm$ were fabricated, which showed excellent current drives of $860\mu\textrm{A}/\mu\textrm{m}$ (NMOS) and $350\mu\textrm{A}/\mu\textrm{m}$ (PMOS) at $I_{off}=10\mu\textrm{A}/\mu\textrm{m}$ and $V_dd=1.2V$, and CV/I of 1.60ps (NMOS) and 3.32ps(PMOS).

• 방사성폐기물학회지
• /
• 제18권4호
• /
• pp.517-536
• /
• 2020

The radionuclide inventory in radioactive waste from nuclear power plants should be determined to secure the safety of final repositories. As an alternative to time-consuming, labor-intensive, and destructive radiochemical analysis, the indirect scaling factor (SF) method has been used to determine the concentrations of difficult-to-measure radionuclides. Despite its long history, the original SF methodology remains almost unchanged and now needs to be improved for advanced SF implementation. Intense public attention and interest have been strongly directed to the reliability of the procedures and data regarding repository safety since the first operation of the low- and intermediate-level radioactive waste disposal facility in Gyeongju, Korea. In this review, statistical methodologies for SF implementation are described and evaluated to achieve reasonable and advanced decision-making. The first part of this review begins with an overview of the current status of the scaling factor method and global experiences, including some specific statistical issues associated with SF implementation. In addition, this review aims to extend the applicability of SF to the characterization of large quantities of waste from the decommissioning of nuclear facilities.

• 한국융합학회논문지
• /
• 제5권3호
• /
• pp.45-51
• /
• 2014

Computer science and computing technologies are applied into mathematical, science, medical, engineering and educational applications. The models are used to solve the issues in all the domains. Educational systems are used top down, bottom up, Gap Analysis model in the educational learning system. Educational learning process integrated with Lerner, content and the methodology. The Learners and content are same in the educational system or similar courses but the teaching methodologies are differing one with another. The determinations of teaching methodologies are based on the factors related to that particular model or subject. The learning model influencing determinations are made by the surveys, analysis and observation of data to maximize the learning outcome. This paper attempted to evaluate the SNE learners cognitive using NASA Scaling.

• 한국농림기상학회지
• /
• 제7권1호
• /
• pp.4-14
• /
• 2005

CarboKorea and HydroKorea are the domestic projects aiming to improve our understanding of carbon and water cycles in a typical Korean forest located in a complex terrain with a watershed connected to large rivers. The ultimate goal is to provide a nowcasting of these cycles for the whole Peninsula. The basic strategy to achieve such goal is through the inter- and multi-disciplinary studies that synthesize the in-situ field observation, modeling and remote sensing technology. The challenge is the fact that natural ecosystems are nonlinear and heterogeneous with a wide range of spatio-temporal scales causing the variations of mass and energy exchanges from a leaf to landscape scales. Our paradigm now shifts from temporal variation at a point to spatial patterns and from spatial homogeneity to complexity of water and carbon at multiple scales. Yet, a large portion of our knowledge about land-atmosphere interactions has been established based on tower observations, indicating that the development of scaling logics holds the key to the success of CarboKorea and HydroKorea. Here, we review the pioneering work of FIFE (First ISLSCP Field Experiment) on scaling issues in a temperate grassland and discuss the lessons from it for the application to Gwangneung forest site.

• 한국버섯학회지
• /
• 제18권1호
• /
• pp.95-99
• /
• 2020

본 연구는 버섯 수출입의 무역역조가 심화되고 있는 상황에서 버섯 수출 확대를 위해 해결해야 할 당면과제들의 우선순위를 도출하는데 목적을 두고 있다. 본 연구는 버섯산업의 부문별 전문가들을 대상으로 집단심층면접조사(FGI)를 실시하여 11개의 당면과제를 발굴한 다음 BWS(Best-Worst Scaling) 분석방법을 이용하여 당면과제들의 우선순위를 도출하였다. 분석결과 11개의 당면과제들 가운데 버섯의 품질 및 가격 경쟁력 강화(1순위)가 가장 중요하고도 시급한 과제로 제시되었다. 그 다음으로는 해외 수출시장 다변화, 버섯의 국내 가격 안정이 각각 2순위와 3순위의 당면과제로 나타났다. 본 연구의 분석결과를 바탕으로 우선순위가 높게 나타난 당면과제들을 해결하기 위한 정책방향을 제시하면 다음과 같다. 첫째, 버섯의 품질 및 가격 경쟁력 강화를 위해서는 다방면에 걸친 유기적인 노력이 필요하다. 생산기반 측면에서 배지원료의 안정적인 수급체계를 구축하고, 우수한 국산 종균의 개발 및 보급을 확대하는 한편 고품질 버섯 안전 생산을 위한 표준재배기술을 개발, 보급하여야 한다. 그리고 장거리 유통이 가능하도록 기능성 포장재를 개발하고, 다양한 수확 후 저장기술(post harvest technology)의 개발을 통하여 품질 및 가격 경쟁력을 높여야 한다. 둘째, 버섯의 해외 수출시장 다변화를 위해서는 STP(segmentation, targeting and positioning) 전략에 맞춰 해외시장을 전략적으로 분할하는 한편 수출 수발주 통합관리 등을 위한 자율적인 통합마케팅조직을 구축하여 수출 창구를 일원화하여야 한다. 또한 해외 마케팅을 강화하고 소비촉진을 위한 다양한 홍보를 추진하여야 한다. 그 일환으로 해외시장 개척 박람회, 판촉행사, 해외마케팅, 바이어(buyer) 초청 등의 행사를 활발하게 추진하여야 한다. 셋째, 버섯의 국내가격 안정을 위해서는 전문유통센터를 건립하여 내수 안정화 및 수출기반을 조성하여야 한다. 버섯은 일반 도매시장을 통하여 유통할 경우 품질관리 및 유통물량 조절이 취약하다는 특성을 지닌다. 따라서 품목별 또는 지역(산지)별로 버섯 전문유통센터를 건립하여 유통효율성을 제고하는 한편 버섯가격 안정화를 도모하여야 한다.