A Survey on Development of Mobile Technology

Now a day?s everything has gone wireless. This is the era of wireless communication. Mobile wireless technology is developed superior techniques. This technology has made incredible growth in the last fifteen years. Through a common wide-area radio-access technology and flexible network architecture WiMAX and LTE has enabled convergence of mobile and fixed broadband networks. This development of mobile technology allows users to utilize common realistic applications such as internet access, location based services, video-on-demand, video conferencing system, mobile financial services, mobile entertainment services and many more applications ,anytime anywhere. This paper gives overview and comparative study of of mobile technologies .The First generation(1G) of wireless telecommunication technology is known as analog cellular telephone. 1G device was comparatively heavy and expensive. Second Generation mobile phones used GSM technology, uses digital modulation and it improves voice quality with limited data service.3G provide faster communication and accommodate web based application and audio video files. Fourth Generation has global mobility support anytime anywhere. Fifth generation focus on (Voice Over IP) VOIP-enabled devices that user will experience a high level of call volume and data transmission. Fifth generation technology will fulfil all the requirements of customers who always want advanced features in cellular phones

Synthesis and properties of N-glycosylimidazoles

In a model study concerned with the mechanism of glycosidase action, six N-glycosylimidazoles and five N-(tetra- O-acetyl-glycosyl) imidazoles have been synthesized by the condensation of the appropriate tetra-O-acetyl-glycosyl halide with imidazole. These compounds have been characterised by their elemental analysis, optical rotation and NMR spectra. In all cases the beta-anomeric compounds predominated over those with alpha-configuration in the reaction products. Analysis of 1H NMR data was carried out on a first order basis,and also by non-iterative and iterative calculation procedures in order to establish the conformations of the N-glycosylimidazoles. The analysis revealed that under certain conditions, in four compounds the sugar pyranose ring is distorted from the normal 4C1 conformation. This distortion has been interpreted in terms of the operation of the reverse anomeric effect. The hydrolytic stabilities of 1-alpha- and beta-D-glucopyranosylimidazoles have been examined in water, pH 3.0 sodium formate buffer, O.56M formic acid, 6N-hydrochloric acid, 10N-sulphuric acid and 1N NaOH. Optical rotation measurements, paper chromatography and analysis for estimation of glucose failed to detect any evidence of hydrolysis. This result is strong evidence against the nucleophilic intervention of a histidinyl side chain in glycosidase action. Hydrolytic cleavage was also attempted with solutions of (yeast) alpha- and (almond) beta-glycosidases, and no glucose was released under conditions in which standard compounds methyl alpha- D-glucoside and cellobiose were hydrolysed significantly. The ORD/CD curves of N-glycosylimidazoles and a series of p-nitrophenyl-glycosides have been examined as an aid to establishing anomeric configurations for N-glycosylimidazoles. In general anomeric pairs of compounds show ORD/CD curves of opposite sign, but some exceptions have been observed in the case of N-glycosylimidazoles. 1-alpha- and beta-D-glucopyranosylimidazoles were found to possess inhibitory properties towards the enzymes (yeast) alpha-glucosidase, (almond) beta-glucosidase and lysozyme. These properties have been investigated in detail. The alpha-anomer shows an unexpectedly high degree of inhibitory behaviour.<p

Effect of Heating on Heat Capacity of Vegetable Oils Used for Biofuel Production

Biodiesel has become a major renewable fuel for diesel engines particularly from various waste sources. New biodiesel production technologies are emerging with data demands for efficient process design. This project highlights the data requirements, gaps in the thermo-physical property data, and consolidation of experimental and estimation methods for effective process development. Knowing the thermodynamic properties of a substance is important in order to know what process or procedures it has to go under. The aim of this project is to assess the potential of vegetable oils to serve as feedstock for biofuel production by determining their heat capacity (Cp). Such oils are common ingredients in daily cooking in every kitchen all over the world, as a result of which there is a lot of leftover oil that is thrown away. To understand the property and alterations of waste oils as a cheaper source for biofuel feedstock, this study has been carried out. A methodology for measuring Cp values was followed with the use of a calorimeter. The oils studied were: canola oil, corn oil and carinata oil. The experimental findings show that as each oil was heated repeatedly, its heat capacity changed and was found to be increasing. The heat capacities of canola, corn and carinata oils increased by 5.01%, 4.08% and 4.46% respectively for five times heated oils compared to virgin oils. This increase is due to compositional changes in the oils on subjecting to heating treatments. The GC-MS analysis show that the PuFAs decrease with every heating cycle while the SFA and one MFA increase. The total amount of PuFA decrease is equivalent to the total amount of SFA and MFA increase, which confirm that there is a conservation of mass and PuFA undergoes saturation on heating

Phase-based visualization and analysis of java programs

Extant JVMs apply dynamic compiler optimizations adaptively, based on the partial execution of the program, with the goal of improving performance. Understanding and characterizing program behavior is of vital importance to such systems. Recent research, primarily in the area of computer architecture, has identified potential optimization opportunities in the repeating patterns in the time-varying behavior of programs. As such, we believe that by con-sidering time-varying, i.e., phase, behavior in Java programs, adaptive JVMs will enable performance that exceeds current levels. To enable analysis and visualization of phase behavior in Java programs and to facilitate optimization devel-opment, we have implemented a freely-available, offline, phase analysis framework within the IBM Jikes Research Virtual Machine (JikesRVM) for Java. The framework couples existing techniques into a unifying set of tools for data collection, processing, and analysis of dynamic phase behavior in Java programs. The framework enables optimiza-tion developers to significantly reduce analysis time and target adaptive optimization to parts of the code that will recur with sufficient regularity. We use the framework to evaluate phase behavior in the SpecJVM benchmark suite and discuss optimizations that are enabled by the framework.

Runahead execution vs. conventional data prefetching in the IBM POWER6 microprocessor

After many years of prefetching research, most commercially available systems support only two types of prefetching: software-directed prefetching and hardware-based prefetchers using simple sequential or stride-based prefetching algorithms. More sophisticated prefetching proposals, despite promises of improved performance, have not been adopted by industry. In this paper, we explore the efficacy of both hardware and software prefetching in the context of an IBM POWER6 commercial server. Using a variety of applications that have been compiled with an aggressively optimizing compiler to use software prefetching when appropriate, we perform the first study of a new runahead prefetching feature adopted by the POWER6 design, evaluating it in isolation and in conjunction with a conventional hardware-based sequential stream prefetcher and compiler-inserted software prefetching. We find that the POWER6 implementation of runahead prefetching is quite effective on many of the memory intensive applications studied; in isolation it improves performance as much as 36 % and on average 10%. However, it outperforms the hardware-based stream prefetcher on only two of the benchmarks studied, and in those by a small margin. When used in conjunction with the conventional prefetching mechanisms, the runahead feature adds an additional 6 % on average, and 39 % in the best case (GemsFDTD). 1

Supporting Exception Handling for Futures in Java

A future is a simple and elegant construct that programmers can use to identify potentially asynchronous computation and to introduce parallelism into serial programs. In its recent 5.0 release, Java provides an interface-based implementation of futures that enables users to encapsulate potentially asynchronous computation and to define their own execution engines for futures. In prior work, we have proposed an alternative model, called directive-based lazy futures (DBLFutures), to support futures in Java, that simplifies Java programmer effort and improves performance and scalability of future-based applications. In the DBLFuture model, programmers use a new directive