We analyze the impact of gate electrode thickness and gate underlap on the fringe capacitance of nanoscale double-gate MOS (DGMOS) transistors. We propose an analytical fringe capacitance model considering gate underlap and finite source/drain length. A comparison with the simulation results show that the model can accurately estimate the fringe capacitance of the device. We show that an optimum gate underlap can significantly reduce the fringe capacitance resulting in higher performance and lower power consumption. Also, the effects of process variation in gate underlap devices are discussed. Simulation results on a three-stage ring oscillator show that with optimum gate underlap 32% improvement in delay can be achieved. 相似文献
One of the main obstacles to the efficient solution of scientific problems is the problem of tuning software, both to the available architecture and to the user problem at hand. We describe approaches for obtaining tuned high-performance kernels and for automatically choosing suitable algorithms. Specifically, we describe the generation of dense and sparse Basic Linear Algebra Subprograms (BLAS) kernels, and the selection of linear solver algorithms. However, the ideas presented here extend beyond these areas, which can be considered proof of concept. 相似文献
A silica-based 1.5%-/spl Delta/ 100 GHz-spacing 32-channel athermal arrayed-waveguide grating (AWG) with compact size and extremely low insertion loss is described. By reducing the fibre coupling loss and the excess loss in a silicone-filled groove, an insertion loss of 1.3 dB was achieved with this athermal AWG. 相似文献
This paper sets out to share BT's leadership and experience by determining the identity management opportunities and issues,
then document the lessons learnt in previous deployments and recommend strategies for all types and sizes of organisation.
Today's ICT environment has created a mixed approach to access management across sectors. Browser-based any time, anywhere,
anyone access, coupled with the business need to access more systems and services across a changing infrastructure of distributed
platforms and networked services, has changed the administrative landscape. Enterprises are being forced to add administrative
support staff or invest in technology-driven process change. At the same time, users are undergoing significant change, creating
new expectations in service quality. Moreover, regulatory bodies are demanding confirmation that processes granting access
are controlled and documented. In this world of increasing demands, complexity and expectation, the service management tools,
techniques and options available to improve user access management are as varied and numerous as the issues faced by management
in their deployment.
Identity management is widely heralded as an opportunity to improve the end user experience, reduce costs, improve security
and deliver regulatory compliance — but is often misunderstood. Projects regularly fail to achieve the expected benefits.
These failures are the result of expectations being inappropriately set, deployment of solutions turning out to be more complex
or taking longer than expected, and/or products selected before required functionality has been determined.
For the larger more mature organisations, or those organisations that are the amalgamation of mergers and acquisitions, the
dilemma is where to start and what approach to take. 相似文献
Lasers based on InAs/InGaAs quantum dots grown on metamorphic (In,Ga,Al)As layers deposited by MBE on GaAs substrates exhibited emission near 1.5 μm with a differential quantum efficiency of about 50%. The narrow-stripe lasers operate in a single transverse mode and withstand continuous current density above 20 kA cm?2 without significant degradation. A maximum continuous-wave output power of 220 mW is obtained. Neither current nor beam filamentation was observed up to the highest pumping levels. 相似文献
We show that the Hardy-Littlewood maximal operator and a class of Calderón-Zygmund singular integrals satisfy the strong type
modular inequality in variable Lp spaces if and only if the variable exponent p(x) ∼ const.
Received: 15 September 2004 相似文献
The restricted Hartree-Fock method was used to determine the cycle size effects on the geometric parameters of several inorganic templates, cyclophosphazenes PnNnX2n (X = H, F, Cl; n = 2, 3, 4). A topological analysis of local electronic properties at the electron density critical points of bonds allowed us to quantitatively characterize the chemical bond in cyclophosphazenes and its dependence on the cycle size and substituents at phosphorus. The calculated distributions of the electron density Laplacian and electron pair localization functions revealed the special features of the electronic structure of the nitrogen and phosphorus atoms. These results explain the nature of noncovalent interactions between the P atoms of one cyclophosphazene molecule and the N atoms of the other. 相似文献
A method for calculating the parameters of formation of vacancies in crystals formed by spherically symmetrical atoms was developed. Both quantum effects at low temperatures and the possibility of the delocalization of atoms at high temperatures were studied. The parameters of formation of vacancies in carbon subgroup element crystals C-diam, Si, Ge, α-Sn, and Pb were calculated. The inclusion of the delocalization of atoms was shown to increase the enthalpy, entropy, and volume of vacancy formation. At low temperatures, the parameters of vacancy formation were found to depend strongly on the temperature, and the entropy of vacancy formation became negative. At high temperatures, close agreement with experimental data and theoretical estimates reported by other authors was obtained. The temperature dependence of vacancy parameters was studied for diamond heated isobarically from 100 to 4500 K. The applicability scope of the Arrhenius equation with a temperature-independent activation energy is discussed. The validity of the “compensation rule” (correlation between the entropy and enthalpy of vacancy formation) was demonstrated. It was also shown that the volume and entropy of vacancy formation were correlated over the whole temperature range studied.
Within the framework of a piecewise homogeneous body model, with the use of three-dimensional geometrically nonlinear exact equations of elasticity theory, a method for determining the stress—strain state in unidirectional fibrous composites with locally curved fibers is developed for the case where the interaction between the fibers is neglected. All the investigations are carried out for an infinite elastic body containing a single locally curved fiber. Numerical results illustrating the effect of geometrical nonlinearity on the distribution of the self-balanced normal and shear stresses acting on the interface and arising as a result of local curving of the fiber are presented.__________Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 433–448, July–August, 2005. 相似文献