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991.
Impact of the discrete dopants on device performance is crucial in determining the behavior of nanoscale semiconductor devices. Atomistic quantum mechanical device simulation for studying the effect of discrete dopants on device's physical quantities is urgent. This work explores the physics of discrete-dopant-induced characteristic fluctuations in 16-nm fin-typed field effect transistor (FinFET) devices. Discrete dopants are statistically positioned in the three-dimensional channel region to examine associated carrier's characteristic, concurrently capturing “dopant concentration variation” and “dopant position fluctuation”. An experimentally validated quantum hydrodynamic device simulation was conducted to investigate the potential profile and threshold voltage fluctuations of the 16-nm FinFET. Results of this study provide further insight into the problem of fluctuation and the mechanism of immunity against fluctuation in 16-nm devices. 相似文献
992.
This paper analyzes the execution behavior of “No Random Accesses” (NRA) and determines the depths to which each sorted file is scanned in growing phase and shrinking phase of NRA respectively. The analysis shows that NRA needs to maintain a large quantity of candidate tuples in growing phase on massive data. Based on the analysis, this paper proposes a novel top-k algorithm Top-K with Early Pruning (TKEP) which performs early pruning in growing phase. General rule and mathematical analysis for early pruning are presented in this paper. The theoretical analysis shows that early pruning can prune most of the candidate tuples. Although TKEP is an approximate method to obtain the top-k result, the probability for correctness is extremely high. Extensive experiments show that TKEP has a significant advantage over NRA. 相似文献
993.
Shoudong Han Author Vitae Author Vitae Xianglin Wu Author Vitae 《Pattern recognition》2011,44(3):503-518
This paper proposes a novel texture segmentation approach using independent-scale component-wise Riemannian-covariance Gaussian mixture model (ICRGMM) in Kullback-Leibler (KL) measure based multi-scale nonlinear structure tensor (MSNST) space. We use the independent-scale distribution and full-covariance structure to replace the covariant-scale distribution and 1D-variance structure used in our previous research. To construct the optimal full-covariance structure, we define the full-covariance on KL, Euclidean, log-Euclidean, and Riemannian gradient mappings, and compare their performances. The comparison experiments demonstrate that the Riemannian gradient mapping leads to its optimum properties over other choices when constructing the full-covariance. To estimate and update the statistical parameters more accurately, the component-wise expectation-maximization for mixtures (CEM2) algorithm is proposed instead of the originally used K-means algorithm. The superiority of the proposed ICRGMM has been demonstrated based on texture clustering and Graph Cuts based texture segmentation using a large number of synthesis texture images and real natural scene textured images, and further analyzed in terms of error ratio and modified F-measure, respectively. 相似文献
994.
In this paper, all cyclic codes with length psn, (n prime to p) over the ring R = Fp + uFp +?+ uk−1Fp are classified. It is first proved that Torj(C) is an ideal of , so that the structure of ideals over extension ring Suk(m,ω)=GR(uk,m)[ω]/〈ωps-1〉 is determined. Then, an isomorphism between R[X]/〈XN − 1〉 and a direct sum ⊕h∈ISuk(mh,ω) can be obtained using discrete Fourier transform. The generator polynomial representation of the corresponding ideals over Fp + uFp +?+ uk−1Fp is calculated via the inverse isomorphism. Moreover, torsion codes, MS polynomial and inversion formula are described. 相似文献
995.
Rob J. Hyndman Roman A. Ahmed George Athanasopoulos Han Lin Shang 《Computational statistics & data analysis》2011,55(9):2579-2589
In many applications, there are multiple time series that are hierarchically organized and can be aggregated at several different levels in groups based on products, geography or some other features. We call these “hierarchical time series”. They are commonly forecast using either a “bottom-up” or a “top-down” method.In this paper we propose a new approach to hierarchical forecasting which provides optimal forecasts that are better than forecasts produced by either a top-down or a bottom-up approach. Our method is based on independently forecasting all series at all levels of the hierarchy and then using a regression model to optimally combine and reconcile these forecasts. The resulting revised forecasts add up appropriately across the hierarchy, are unbiased and have minimum variance amongst all combination forecasts under some simple assumptions.We show in a simulation study that our method performs well compared to the top-down approach and the bottom-up method. We demonstrate our proposed method by forecasting Australian tourism demand where the data are disaggregated by purpose of travel and geographical region. 相似文献
996.
A factor combination approach to developing style guides for mobile phone user interface 总被引:1,自引:0,他引:1
Wonkyu ParkSung H. Han Sungjin KangYong S. Park Jaemin Chun 《International Journal of Industrial Ergonomics》2011,41(5):536-545
This paper proposes a systematic approach to developing comprehensive guidelines for mobile phone user interface, and presents a case study to validate the approach. The approach applies a systematic combination of three critical factors: general usability principles, UI components and guideline properties to developing guidelines. In the case study, this factor combination approach was very effective in collecting experts’ ideas, creating guidelines and editing them. The resulting style guide can provide comprehensive and useful guidelines for designing mobile phone UI.
Relevance to Industry
UI designers can use the results of the study as a practical method to develop style guides for mobile phone UIs. The approach taken in the study will also be helpful in managing complex guideline information systematically. 相似文献997.
Dong Han Kim 《Theoretical computer science》2011,412(29):3413-3417
998.
999.
污水处理过程具有多变量、非线性、大滞后和强耦合的特点,建立精确的数学模型十分困难,为了精确的描述污水处理过程,本文将1种改进型的递归神经网络应用在污水处理过程建模中,建立了污水处理过程关键水质参数的智能模型。Elman网络作为1种动态神经网络,网络的动态特性可以很好的反映系统的内部动力学特征,但是标准的Elman网络只对隐含层的输出进行了反馈,并且只反馈给了隐含层的输入,反馈信息较少。针对此问题,本文提出1种改进型的Elman网络(OAF Elman网络),增加了输出层的反馈信息,将反馈信息既传给隐含层输入又传给输出层的输入,同时将隐含层的反馈也作为输入层的输入,使网络的输出包含更多的输入信息,能够更好的反映系统的时变、非线性等特征。采集污水处理厂生化反应过程实际运行数据,取对COD影响较大的MLVSS、进水COD、pH值、氨氮4个种指标作为递归神经网络模型的输入,对污水出水的关键水质参数COD进行建模,网络的训练误差达到0.011,测试误差达到0.4875。实验结果表明:与传统的Elman网络和其他几种改进型的Elman网络相比,本文提出的OAF Elman网络具有更丰富的动力学特性,建立的污水处理模型达到... 相似文献
1000.
本文基于TETRA制式的特点和在我国城市轨道交通的应用情况,提出了重庆地铁一号线TETRA系统无线覆盖规划方法,对信道数、用户容量和区间切换等技术指标进行了分析,并对无线链路指标和组网结构进行了设计。 相似文献