Threads play a major role in applications programming today. For example, most Web servers are threaded, as are many Java GUI programs. Here are the major settings in which using threads has been founded convenient and/or efficient:
• Programs with asynchronous events:
Here the program must be ready for various events, but does not know the order in which they might occur. For example, in Sections 3.1 and 3.2, we have a network server connected to several clients. The server does not know from which client the next message will arrive. So, we have the server create a separate thread for each client, with each thread handling only its client.
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Adaptive algorithms are an important technique to achieve portable high performance. They choose among solution methods and optimizations according to expected performance on a particular machine. Grid environments make the adaptation problem harder, because the optimal decision may change across runs and even during runtime. Therefore, the performance model used by an adaptive algorithm must be able to change decisions without high overhead. In this paper, we present work that is modifying previous research into rapid performance modeling to support adaptive grid applications through sampling and high granularity modeling. We also outline preliminary results that show the ability to predict differences in performance among algorithms in the same program.
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The following document is intended as a guideline for developing secure web-based applications. It is not about how to configure firewalls, intrusion detection, DMZ or how to resist DDoS attacks. This is a task best addressed at system and network level. However, there is little material available today intended for developers. We have entered the dotcom age in which a web site is no longer an isolated site, but an extension of the internal business systems, yet there isn’t much about how to create this extension securely.
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GNS3 is a Graphical Network Simulator that allows emulation of complex networks. You may be familiar with VMWare or Virtual PC that are used to emulate various operating systems in a virtual environment. These programs allow you to run operating systems such as Windows XP Professional or Ubuntu Linux in a virtual environment on your computer. GNS3 allows the same type of emulation using Cisco Internetwork Operating Systems. It allows you to run a Cisco IOS in a virtual environment on your computer. GNS3 is a graphical front end to a product called Dynagen. Dynamips is the core program that allows IOS emulation. Dynagen runs on top of Dynamips to create a more user friendly, text-based environment. A user may create network topologies using simple Windows ini-type files with Dynagen running on top of Dynamips. GNS3 takes this a step further by providing a graphical environment.
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VueStar™ is the only complete global aerial survey navigation system. VueStar™ delivers precision navigation by combining NavCom’s leading edge, dual frequency GPS receiver with NavCom’s StarFire™ Network, a Global Satellite Based Augmentation System (GSBAS). The VueStar™ system, equipped with a single FAA certified tri-band antenna that receives both GPS and StarFire™ signals, provides decimeter navigation in real-time without the need for local base stations.
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Facebook is one of the most popular Internet sites today. A key feature that arguably contributed to Facebook’s unprecedented success is its application platform, which enables the development of third-party social-networking applications. Understanding how these applications are installed and used is important for the function and utility of web-based online social networks, e.g. to better engineer them and/or to design advertising campaigns.
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Electronic communication has been redefining the ways in which people communicate with each other since its wide-spread introduction in the 1990’s. E-mail, instant messaging, internet forums, and social networking have added entirely new meanings to interpersonal interaction and community. Through time, internet based communication has developed its own set of non-verbal communication (emoticons, select usage of certain punctuation, chat speak, etc.) Like all other communication technologies, it has also been adapted into everyday life and everyday communication (by those that have access of course).
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When Symbian was formed 10 years ago, it inherited a browser from Psion. In the following years, the ability to browse real Web pages became a key differentiator of smartphones as compared to feature phones, and so Web technologies have played an important role in the story of Symbian. At the time of Symbian’s formation, there was much debate in the industry on whether the future of personal and enterprise computing would be in thick or thin clients – that is, in rich client software running mainly on the phone, or software hosted on a network server with a fairly simple browsing terminal. Ten years later and we see AJAX blurring the gap between the notion of thin and thick clients with rich browsing terminals backed with colossal arrays of servers dishing out email, photos, twitters and Facebook messages.
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