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181.
We investigate the effect of dopant random fluctuation on threshold voltage and drain current variation in a two-gate nanoscale transistor. We used a quantum-corrected technology computer aided design simulation to run the simulation (10000 randomizations). With this simulation, we could study the effects of varying the dimensions (length and width), and thicknesses of oxide and dopant factors of a transistor on the threshold voltage and drain current in subthreshold region (off) and overthreshold (on). It was found that in the subthreshold region the variability of the drain current and threshold voltage is relatively fixed while in the overthreshold region the variability of the threshold voltage and drain current decreases remarkably, despite the slight reduction of gate voltage diffusion (compared with that of the subthreshold). These results have been interpreted by using previously reported models for threshold current variability, load displacement, and simple analytical calculations. Scaling analysis shows that the variability of the characteristics of this semiconductor increases as the effects of the short channel increases. Therefore, with a slight increase of length and a reduction of width, oxide thickness, and dopant factor, we could correct the effect of the short channel.  相似文献   
182.
在简述V.35接口的基础上针对V.35接口速率可变的应用需求提出了一种速率可变的帧结构,该帧结构可支持N×64kb/s(3≤N≤32)速率,从而在V.35接口上实现了多种速率的低速业务传输.  相似文献   
183.
Mass concentration and isotopic values δ13C and 14C are presented for the water-insoluble refractory carbon(WIRC) component of total suspended particulates(TSP),collected weekly during 2003,as well as from October 2005 to May 2006 at the WMO-GAW Mt.Waliguan(WLG) site.The overall average WIRC mass concentration was(1183±120)ng/m3(n = 79),while seasonal averages were 2081 ±1707(spring),454±205(summer),650±411(autumn),and 1019±703(winter) ng/m3.Seasonal variations in WIRC mass concentrations were consistent with black carbon measurements from an aethalometer,although WIRC concentrations were typically higher,especially in winter and spring.The δ13C PDB value(-25.3 ± 0.8)%.determined for WIRC suggests that its sources are C3 biomass or fossil fuel combustion.No seasonal change in δ13C PDB was evident.The average percent Modern Carbon(pMC) for 14C in WIRC for winter and spring was(67.2 ± 7.7)%(n = 29).Lower pMC values were associated with air masses transported from the area east of WLG,while higher pMC values were associated with air masses from the Tibetan Plateau,southwest of WLG.Elevated pMC values with abnormally high mass concentrations of TSP and WIRC were measured during a dust storm event.  相似文献   
184.
Let R be a Noetherian unique factorization domain such that 2 and 3 are units,and let A=R[α]be a quartic extension over R by adding a rootαof an irreducible quartic polynomial p(z)=z4+az2+bz+c over R.We will compute explicitly the integral closure of A in its fraction field,which is based on a proper factorization of the coefficients and the algebraic invariants of p(z).In fact,we get the factorization by resolving the singularities of a plane curve defined by z4+a(x)z2+b(x)z+c(x)=0.The integral closure is expressed as a syzygy module and the syzygy equations are given explicitly.We compute also the ramifications of the integral closure over R.  相似文献   
185.
电力系统发展到今天,高压输配电无处不在,与此同时,高压引发的一些事故也引起了人们的关注。控制好高压安全距离是防止高压触电事故的根本措施,而传统的警示牌警示作用有限,在一些大雾大雪天气几乎起不到作用。本系统采用微波探测器与红外探测器双踪探测,灵敏度高,抗干扰能力强。采用声光报警系统,警示作用明显,能够很有效地控制高压危险距离,防止高压触电事故。  相似文献   
186.
缓发中子有效份额βeff是反应堆动态特性的重要参数,也是相对反应性与绝对反应性之间的转换桥梁,对于以反应性作为宏观参数的检验工作具有重要意义。测量采用基于Rossi-α方法的Nelson数法开展了快临界装置βeff的实验研究。通过采用铅屏蔽、更薄的6Li玻璃闪烁体、脉冲幅度甄别三种措施,降低了γ射线对测量的影响。实验中测量了反应堆从-60¢到缓发临界之间的7个状态,最终测量得到βeff值为0.006 66,不确定度为7.88%;与理论计算数值偏差为2.15%。测量结果与理论值符合良好,表明了测量方法的有效性。  相似文献   
187.
针对智能化柔性制造过程存在的再制造过程,对中小型设备生产车间及其仓储转运的模型构建、分析方法、以及参量相关性提出了新的解决思路.为了最大限度的减少建设周期、合理化投资成本、以及优化生产流程,建立了考虑非结构性的多级生产流程的数学模型,以完成度、完工时间和调度频次为目标函数分析生产要素间的相关性.实验结果表明,融合再加工过程的智能化柔性制造单元中,生产要素为非线性相关,个别要素具备对称性,为实际工况中的生产改进及优化提供了一定理论基础.  相似文献   
188.
Three small bandgap non-fullerene(SBG NFAs) acceptors,BDTI,BDTI-2 F and BDTI-4 F,based on a carbon-oxygen bridged central core and thieno[3,4-b]thiophene linker,end-capped with varied electronwithdrawing terminal groups,were designed and synthesized.The acceptors exhibit strong absorption from 600 nm to 1000 nm.The optimal device incorporating designed NFA and PTB7-Th polymer donor achieves a power conversion efficiency of 9.11% with near 0 eV HOMO offset.The work presents a case study of efficient non-fullerene solar cells with small HOMO offsets,which is achieved by blending PTB7-Th with fine-tuned SBG acceptor.  相似文献   
189.
建立了一套基于刀口灰度图红外探测的实验装置,对红外场景生成器的空间分辨率进行了测试。首先通过被测红外场景生成器产生带有刀口标志的红外图像,然后利用红外热像仪采集红外场景生成器所成的红外图像,通过对采集到的红外热图的数据处理,实现了对红外场景生成器空间分辨率的测量。测得的红外场景生成器的空间分辨率为5lp/mm,标准误差为0.04。  相似文献   
190.
The rapid technological convergence between Internet of Things(IoT),Wireless Body Area Networks(WBANs)and cloud computing has made e-healthcare emerge as a promising application domain,which has significant potential to improve the quality of medical care.In particular,patient-centric health monitoring plays a vital role in e-healthcare service,involving a set of important operations ranging from medical data collection and aggregation,data transmission and segregation,to data analytics.This survey paper firstly presents an architectural framework to describe the entire monitoring life cycle and highlight the essential service components.More detailed discussions are then devoted to {\em data collection} at patient side,which we argue that it serves as fundamental basis in achieving robust,efficient,and secure health monitoring.Subsequently,a profound discussion of the security threats targeting eHealth monitoring systems is presented,and the major limitations of the existing solutions are analyzed and extensively discussed.Finally,a set of design challenges is identified in order to achieve high quality and secure patient-centric monitoring schemes,along with some potential solutions.  相似文献   
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