Gaussian lower bounds for non-homogeneous Kolmogorov equations with measurable coefficients

We prove Gaussian upper and lower bounds for the fundamental solutions of a class of degenerate parabolic equations satisfying a weak Hörmander condition. The bound is independent of the smoothness of the coefficients and generalizes classical results for uniformly parabolic equations

Moser's estimates for degenerate Kolmogorov equations with non-negative divergence lower order coefficients

We prove Lloc 1e estimates for positive solutions to the following degenerate second order partial differential equation of Kolmogorov type with measurable coefficients of the form 11i,j=1m0 02xjavax.xml.bind.JAXBElement@14c7905daij(x,t) 02xjavax.xml.bind.JAXBElement@41a3b5feu(x,t)+ 11i,j=1Nbijxj 02xjavax.xml.bind.JAXBElement@21dceba6u(x,t) 12 02tu(x,t)++ 11i=1m0bi(x,t) 02iu(x,t) 12 11i=1m0 02xjavax.xml.bind.JAXBElement@638b72d3ai(x,t)u(x,t)+c(x,t)u(x,t)=0 where (x,t)=(x1,\u2026,xN,t)=z is a point of RN+1, and 1 64m0 64N. (aij) is a uniformly positive symmetric matrix with bounded measurable coefficients, (bij) is a constant matrix. We apply the Moser's iteration method to prove the local boundedness of the solution u under minimal integrability assumption on the coefficients

The use of patrol craft in low intensity conflict operations: an alternative model for the employment of the Cyclone-class (PC-1)

The post-Cold War era has posed a significant challenge to the U.S. Navy. The absence of a major, blue-water, naval threat has allowed the Navy to shift its focus toward the littoral arena and to develop strategies and tactics for operations close to shore. While it is hard to dispute the need for the combat power of a carrier battle group in wartime its firepower is less necessary or applicable in low intensity conflict (LIC) operations. Patrol craft, particularly the Cyclone-class (PC-1), are ideally suited for LIC. These 'niche' craft offer a valuable contribution to the close-in, coastal patrol and interdiction mission and to naval special warfare support. Unfortunately for the PCs, the institutional bias of the U.S. Navy favors multi- mission capable 'big ships' and small craft programs are often deemed non-competitive and are ignored. The thesis examines this problem through the lens of bureaucratic politics theory and uses it to compare the similarity of arguments for and against the PHM and PC programs. In an attempt to create an alternative model for PC employment, based on the mother ship/scout-fighter concept, the thesis also investigates how foreign coastal navies employ their patrol craft. The study concludes with a recommendation to more heavily involve the PCs in LIC and contingency operations and make them part of the Navy's forward presence mission.http://archive.org/details/theuseofpatrolcr1094531358NANAU.S. Navy (U.S.N.) author

SIP-based mobility management in next generation networks

The ITU-T definition of next generation networks includes the ability to make use of multiple broadband transport technologies and to support generalized mobility. Next generation networks must integrate several IP-based access technologies in a seamless way. In this article, we first describe the requirements of a mobility management scheme for multimedia real-time communication services; then, we report a survey of the mobility management schemes proposed in the recent literature to perform vertical handovers between heterogeneous networks. Based on this analysis, we propose an application-layer solution for mobility management that is based on the SIP protocol and satisfies the most important requirements for a proper implementation of vertical handovers. We also implemented our proposed solution, testing it in the field, and proving its overall feasibility and its interoperability with different terminals and SIP servers

CO2-assisted hydrolytic hydrogenation of cellulose and cellulose-based waste into sorbitol over commercial Ru/C

A single-step protocol was developed for the hydrolytic hydrogenation of microcrystalline cellulose into sorbitol over commercial carbon-supported Ru, in the presence of gaseous CO2 as an acid source and molecular hydrogen as a reductant. Under these conditions, cellulose was first hydrolysed to glucose by reversibly formed carbonic acid in water and then instantaneously hydrogenated on Ru/C. By tuning the reaction parameters, such as temperature, time and the relative pressure of CO2 and hydrogen gas, cellulose was fully converted at 220 & DEG;C in 18 h under 30 and 40 bar of H-2 and CO2, respectively, with a sorbitol yield of 81%. Blank experiments revealed that without a catalyst and hydrogen, the reaction exhibited <5% conversion and glucose was the only detected product when the reaction was performed under CO2 pressure. XRD measurements on CO2-treated cellulose surprisingly revealed no noticeable changes in the crystallinity index (<10% with respect to microcrystalline cellulose), suggesting that hydrolytic hydrogenation took place on crystalline, not amorphous, cellulose. Furthermore, not only several cellulosic feedstocks, including filter paper, cotton wool, and cotton fiber, but also typical cellulose-based wastes such as a cardboard pizza box were also tested and under the optimized conditions sorbitol was obtained with yields ranging from 56% up to 72% in all cases. No less significant was the Ru/C catalyst stability, which could be recycled at least six times without any noticeable activity loss

Conservation Status of Marine Biodiversity in Oceania: An Analysis of Marine Species on the IUCN Red List of Threatened Species

Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciformfish groups. Many of the species in these groups are threatened by themodification or destruction of coastal habitats, overfishing fromdirect or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania,many important fish groups are still in urgent need of assessment