A new asymmetric 6T SRAM cell with a write assist technique in 65 nm CMOS technology

A new asymmetric 6T-SRAM cell design is presented for low-voltage low-power operation under process variations. The write margin of the proposed cell is improved by the use of a new write-assist technique. Simulation results in 65 nm technology show that the proposed cell achieves the same RSNM as the asymmetric 5T-SRAM cell and 77% higher RSNM than the standard 6T-SRAM cell while it is able to perform write operation without any write assist at V_DD=1 V. Monte Carlo simulations for an 8 Kb SRAM (256×32) array indicate that the scalability of operating supply voltage of the proposed cell can be improved by 10% and 21% compared to asymmetric 5T- and standard 6T-SRAM cells; 21% and 53% lower leakage power consumption, respectively. The proposed 6T-SRAM cell design achieves 9% and 19% lower cell area overhead compared with asymmetric 5T- and standard 6T-SRAM cells, respectively. Considering the area overhead for the write assist, replica column and the replica column driver of 2.6%, the overall area reduction in die area is 6.3% and 16.3% as compared with array designs with asymmetric 5T- and standard 6T-SRAM cells.     

主动、被动大陆边缘天然气水合物成藏模式对比

不同大陆边缘（主动、被动）沉积物中天然气水合物（以下简称水合物）赋存的控制因素与成藏模式有所差异，开展二者之间的对比研究对于指导水合物勘探具有重要的意义。为此，以主动大陆边缘卡斯凯迪亚（Cascadia）和日本南海（Nankai）海槽、被动大陆边缘布莱克海台（Blake Ridge）和尼日尔三角洲盆地（Niger Delta Basin）等典型水合物成藏区为研究对象，借助于综合大洋钻探（IODP）航次资料解剖和数值模拟分析等手段，从应力场的角度探讨了上述两种背景下含甲烷流体的驱动样式，进而对比分析了主动、被动大陆边缘水合物的成藏模式。研究结果表明：①主动大陆边缘以侧向挤压应力为气体垂向运移提供了驱动力和通道，引诱深部游离气和原位生物气沿断裂运移，气体运移通道主要为俯冲—增生产生的断层、断裂和滑塌体；②主动大陆边缘粉砂和砂质粉砂等粗粒浊流沉积孔隙度大、渗透性好，并且增生楔上沉积物厚度大，是水合物成藏较为有利的储集空间；③较之于主动型大陆边缘，被动大陆边缘虽然缺少俯冲带造成的侧向应力，但在其内巨厚沉积层塑性物质及高压流体、陆缘外侧火山活动等的共同作用下，产生垂向加积和拉张应力，形成的扩散型水合物聚集速率主要取决于甲烷的供给速度；④被动大陆边缘有机质含量、产气速率、地温梯度及沉积速率对水合物含量空间分布具有差异性影响，泥火山或底辟构造等为水合物的形成与赋存提供了理想的场所。     

Dose-mortality assessment on municipal solid waste incinerator (MSWI) ash

This study provides a novel attempt to put forward, in general toxicological terms, quantitative series of toxicity of various ashes of municipal solid waste incinerator (MSWI) for reusability in various applications. Previous study disclosed that growth inhibition of Escherichia coli DH5alpha occurred at concentrations above 0.156, 0.625 and 0.0195 gL(-1) for bottom ash (BA), cyclone ash (CA), scrubber ash (SA), respectively, suggesting the toxicity series of SA>BA>CA. However, the severity of such a toxicity series was not clearly revealed, thus whether ashes were still feasible for reuse in further applications was still remained uncertain. Compared to NaNO3, CrCl2 and CdCl2, the existing toxicities of ashes were apparently significant even these ashes were all satisfied by the TCLP guidelines for EPA regulations. Dose-response analysis based upon loss of cell viability (e.g., EC50) stated a toxicity series of SA>CrCl2>BA>CdCl2>CA>NaNO3. The ranking of Hill slope B in BA>SA>CA>NaNO3>CrCl2>CdCl2 clearly suggested the smallest tolerance (e.g., ranges from EC20 to EC50) for ashes very likely due to synergistic toxicity of multiple species present in ashes. The findings showed that toxicity attenuation of ashes should be the first-ranking task prior to practical reuse and recycle in applications.     

Impact of lateral straggle on analog and digital circuit performance using independently driven underlap DG-MOSFET

In this work, the effect of lateral straggle on independently driven underlap double gate MOSFET (IDUDGMOS) is presented based on analog and digital circuit performances. The lateral straggle in IDUDGMOS devices is due to process induced source/drain out diffusion and it varies the desired device characteristics. For the analysis of this variation on circuit performance of the device, an Amplitude Modulator (AM) circuit and a SRAM circuit is considered for analog and digital circuit application considerations respectively. For the analysis of the device in AM circuit the parameters studied are the bandwidth, the gain and the linearity, correspondingly for SRAM circuit the parameters studied are the Static Noise Margin (SNM) and the circuit delay. The analysis of the AM circuit designed using the IDUDGMOS suggested that the power loss and the bandwidth of the circuit degrade with increasing lateral straggle. For the SRAM circuit the analysis suggests that larger straggle lengths in the device results in reduced time delay but, the SNM is smaller as well.     

公共矢量的最小类内方差SVM与噪音人脸分类

提出基于公共矢量的最小类内方差支持向量机（CV-MCVSVM）,用于提高噪音人脸图像分类问题中的抗噪性能。它继承了最小类内方差支持向量机（MCVSVMs）的优点,引入了由公共矢量（CVs）构成的散度矩阵Scom,由于CVs包含了样本中的共同信息,因此CV-MCVSVM在定义中将每个样本减去了CVs的均值,保留了更多的分类信息,进一步提高了抗噪能力。给出了CV-MCVSVM的推导过程。经实验验证,在含有噪音人脸图像的分类问题中,CV-MCVSVM获得了比MCVSVMs和总间隔v-支持向量机（TM-v-SVM）更好的分类性能。