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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
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Marco Deveglia 《数码世界》2004,3(17)
根据哈佛商学院最著名的教授MichaelPorte r的观点:"运营效率意味着你能在一场赛跑中跑得更快,而战略却能帮你选择一场能最终获胜的赛跑."(引自"Michael Porte r归来",<财富>1999年2月刊.)现今,客户满意度--令客户喜欢你的产品及服务的程度,取决于企业的运营效率.因此,将企业比作一艘船,如果船即将撞上冰山,即使你能令乘客满意到最后,但却不能避免整艘船的沉没.要想成功绕开冰山,你只有想出优于对手的战略. 相似文献
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Larissa Canilha Walter Carvalho Marco Giulietti Maria Das Graças Almeida Felipe João Batista Almeida E Silva 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(5):715-721
BACKGROUND: Xylitol bioproduction from lignocellulosic residues comprises hydrolysis of the hemicellulose, detoxification of the hydrolysate, bioconversion of the xylose, and recovery of xylitol from the fermented hydrolysate. There are relatively few reports on xylitol recovery from fermented media. In the present study, ion‐exchange resins were used to clarify a fermented wheat straw hemicellulosic hydrolysate, which was then vacuum‐concentrated and submitted to cooling in the presence of ethanol for xylitol crystallization. RESULTS: Sequential adsorption into two anion‐exchange resins (A‐860S and A‐500PS) promoted considerable reductions in the content of soluble by‐products (up to 97.5%) and in medium coloration (99.5%). Vacuum concentration led to a dark‐colored viscous solution that inhibited xylitol crystallization. This inhibition could be overcome by mixing the concentrated medium with a commercial xylitol solution. Such a strategy led to xylitol crystals with up to 95.9% purity. The crystallization yield (43.5%) was close to that observed when using commercial xylitol solution (51.4%). CONCLUSION: The experimental data demonstrate the feasibility of using ion‐exchange resins followed by cooling in the presence of ethanol as a strategy to promote the fast recovery and purification of xylitol from hemicellulose‐derived fermentation media. Copyright © 2008 Society of Chemical Industry 相似文献
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By analyzing an oblique ionogram several characteristics, such as LOF, MOF, FMUF, FHLOF, FLLOF, and 2FMOF, can be found. These characteristics are important both for ionospheric studies and for terrestrial communication purposes, as they give information about the sky wave communication conditions in the High Frequency (HF) radio spectrum.A RCS-5B sweeping HF receiver for oblique sounding was installed at Chania (Crete, Greece, 35.7°N, 24.0°E) in April 2005 to perform a radio link with Inskip (UK, 53.5°N, 2.5°W). The receiver, able to record the sounding only as a binary file, was not equipped with a tool to display and scale the recorded trace. This work describes software that is able to do this, consequently increasing the speed of the scaling phase performed by the operator. The usefulness of this software for validating FMUF prediction models is also shown. 相似文献
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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
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Years have lapsed since the inauguration of the first Wireless Application Protocol (WAP) application. One of the main reasons for the lukewarm response so far may be attributed to the lack of a “Killer” application. Many companies and developers have attempted to replicate email services (an Internet Killer appplication) within the WAP realm, but till now, no significant success has been reported. This paper will first discuss on the key functions which are lacking in the present WAP-email service, and which are arguably necessary if a much larger user base is to be attracted to these services. A new system will be proposed which can enable the user to send files residing in a remote personal computer (PC) as attachments to his emails using WAP-enabled mobile devices. The implementation of the system will be presented in details. Issue relating to the connection to various types of email servers and the security of the system will also be addressed in the paper. 相似文献