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1.
Navab SinghAuthor Vitae Moitreyee Mukherjee-RoyAuthor VitaeSohan Singh MehtaAuthor Vitae 《Microelectronics Journal》2003,34(4):237-245
The patterning of contact holes by selecting out-of-focus image plane (defocus) using attenuated phase shift masks (APSM) has been studied. Defocus is found to enhance the image modulation at low partial coherence for contact holes with negative local average of mask function. Semi-dense holes up to 130 nm in 8% APSM have been printed by 0.5 μm defocus at a partial coherence of 0.31 using KrF scanner with highest numerical aperture of 0.68. However, these holes were closed with in-focus imaging. Defocus is also found to be beneficial for patterning the pitches that have extensive side lobes with in-focus imaging. 相似文献
2.
Patrick R. Taylor Ph.D. Milton Manrique Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1996,48(6):43-45
Due to several inherent advantages, plasma processing technology may become a very useful tool in the production of new materials. An increasing research effort based on experimental as well as theoretical investigations has been invested in this area for the synthesis of advanced materials. In describing the thermal-plasma processing technique, this article employs examples from research at the Plasma Processing Laboratory at the University of Idaho. 相似文献
3.
Under carefully chosen conditions, solidification theory may be applied to solid-state transformations, and this has been
done here for composition-invariant diffusion transformations. The predictions of the modeling are compared with isovelocity
experiments in two iron systems, Fe-7.29 wt pct Cr and Fe-3.1 wt pct Ni. The ferrite to austenite phase transformation is
used to demonstrate that stabilization of a planar transformation front at absolute stability is the natural lower velocity
limit for a composition-invariant (massive) transformation. The results of the model, which includes nonequilibrium effects,
clearly show that steady-state plane-front growth leading to composition invariance can be obtained at various temperatures
depending on the growth velocity. In the lower velocity range, at the limit of absolute stability (of the order of 10 μm/s in the systems studied), the transformation interface moves under conditions of local equilibrium, and the temperature
corresponds to the lower solvus temperature. At higher velocity (of the order of the interface diffusion rate, which in these
systems is of the order of cm/s), the transformation is predicted to proceed at temperatures close to T
0. At even higher rates, atom attachment kinetic undercooling will decrease the transformation temperature with respect to
T
0. In some cases, this temperature might even drop below the lower solvus.
This article is based on a presentation made at the symposium entitled “The Mechanisms of the Massive Transformation,” a part
of the Fall 2000 TMS Meeting held October 16–19, 2000, in St. Louis, Missouri, under the auspices of the ASM Phase Transformations
Committee. 相似文献
4.
A stochastic realization problem of a stationary stochastic process is re-visited, and a new stochastically balanced realization algorithm is derived in a Hilbert space generated by second-order stationary processes. The present algorithm computes a stochastically balanced realization by means of the singular value decomposition of a weighted block Hankel matrix derived by a “block LQ decomposition”. Extension to a stochastic subspace identification method explains how the proposed abstract algorithm is implemented in system identification. 相似文献
5.
6.
Chia-Jung Pai Author Vitae Author Vitae Yu-Ming Liang Author Vitae Author Vitae Sei-Wang Chen Author Vitae 《Pattern recognition》2004,37(5):1025-1034
This paper presents a system that can perform pedestrian detection and tracking using vision-based techniques. A very important issue in the field of intelligent transportation system is to prevent pedestrians from being hit by vehicles. Recently, a great number of vision-based techniques have been proposed for this purpose. In this paper, we propose a vision-based method, which combines the use of a pedestrian model as well as the walking rhythm of pedestrians to detect and track walking pedestrians. Through integrating some spatial and temporal information grabbed by a vision system, we are able to develop a reliable system that can be used to prevent traffic accidents happened at crossroads. In addition, the proposed system can deal with the occlusion problem. Experimental results obtained by executing some real world cases have demonstrated that the proposed system is indeed superb. 相似文献
7.
V. Rodin Author Vitae A. Benzinou Author VitaeAuthor Vitae P. Ballet Author VitaeAuthor Vitae J. Tisseau Author VitaeAuthor Vitae 《Pattern recognition》2004,37(4):631-645
In this article, we present a parallel image processing system based on the concept of reactive agents. Our system lies in the oRis language, which allows to describe finely and simply the agents’ behaviors to detect image features. We also present a method of segmentation using a multi-agent system, and two biological applications made with oRis. The stopping of this multi-agent system is implemented through a technique issued from immunology: the apoptosis. 相似文献
8.
9.
Er-Wei Bai Author Vitae 《Automatica》2003,39(9):1521-1530
This paper proposes a frequency domain algorithm for Wiener model identifications based on exploring the fundamental frequency and harmonics generated by the unknown nonlinearity. The convergence of the algorithm is established in the presence of white noise. No a priori knowledge of the structure of the nonlinearity is required and the linear part can be nonparametric. 相似文献
10.
Qing-Chang Zhong Author Vitae 《Automatica》2003,39(3):499-508
This paper generalizes the frequency-domain results on the delay-type Nehari problem in the stable case to the unstable case. The solvability condition of the delay-type Nehari problem is formulated in terms of the nonsingularity of three matrices. The optimal value γopt is the maximal γ∈(0,∞) such that one of the three matrices becomes singular. All sub-optimal compensators are parameterized in a transparent structure incorporating a modified Smith predictor. 相似文献