E-Commerce
October 15, 2009| ID#6404 | |||||
| |||||
e commerce
October 13, 2009FOR SALE:
Beautiful Countryside Property,
Lot area: 20,000 sq. meters
A beautiful countryside property with lots of big old trees located along the national highway and just 2 km. away from the town center and 1 hour from Dumaguete. Can be utilized for residential, agricultural, or commercial purposes. Can be turned into a nature park/resort or organic farm. Titled property.
 |
Great opportunity with a great lifestyle. A very reluctant sale at Boracay,Malay,Aklan
Types of Topology
September 1, 2009Network topology is the physical or logical arrangement and interconnections of the elements (links, nodes, etc.) of a computer network. A local area network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN has one or more links to one or more other nodes in the network and the mapping of these links and nodes in a graph results in a geometrical shape that may be used to describe the physical topology of the network.
Basic topology types
The study of network topology recognizes three basic topologies:
- Bus topology
- Star topology
- Ring topology
Classification of network topologies
-
There are also three basic categories of network topologies:
-
- physical topologies
- signal topologies
- logical topologies
The terms signal topology and logical topology are often used interchangeably, though there is a subtle difference between the two.
Physical topologies
-
The mapping of the nodes of a network and the physical connections between them - the layout of wiring, cables, the locations of nodes, and the interconnections between the nodes and the cabling or wiring system[1].
-
Classification of physical topologies
The simplest topology is a permanent link between two endpoints. Switched point-to-point topologies are the basic model of conventional telephony. The value of an on-demand point-to-point connection is proportional to the number of potential pairs of subscribers, and has been expressed as Metcalfe’s Law.
-
Permanent (dedicated)
- Easiest to understand, of the variations of point-to-point topology, is a point-to-point communications channel that appears, to the user, to be permanently associated with the two endpoints. Children’s “tin-can telephone” is one example, with a microphone to a single public address speaker is another. These are examples of physical dedicated channels.Within many switched telecommunications systems, it is possible to establish a permanent circuit. “Nailing down” a switched connection saves the cost of running a physical circuit between the two points.
-
Switched:
-
-
- Using circuit-switching or packet-switching technologies, a point-to-point circuit can be set up dynamically, and dropped when no longer needed. This is the basic mode of conventional telephony.
Bus
- In local area networks where bus technology is used, each machine is connected to a single cable. Each computer or server is connected to the single bus cable through some kind of connector. A terminator is required at each end of the bus cable to prevent the signal from bouncing back and forth on the bus cable.
- Linear bus
-
- The type of network topology in which all of the nodes of the network are connected to a common transmission medium which has exactly two endpoints (this is the ‘bus’, which is also commonly referred to as the backbone, or trunk) – all data that is transmitted between nodes in the network is transmitted over this common transmission medium and is able to be received by all nodes in the network virtually simultaneously (disregarding propagation delays).
Distributed bus
- All of the nodes of the network are connected to a common transmission medium which has more than two endpoints that are created by adding branches to the main section of the transmission medium – the physical distributed bus topology functions in exactly the same fashion as the physical linear bus topology (i.e., all nodes share a common transmission medium).
- Star
-
-
-
Star network topologyIn local area networks where the star topology is used, each machine is connected to a central hub. In contrast to the bus topology,allows each machine on the network to have a point to point connection to the central hub.
-
- A network that is based upon the physical star topology has one or more repeaters between the central node (the ‘hub’ of the star) and the peripheral or ’spoke’ nodes, the repeaters being used to extend the maximum transmission distance of the point-to-point links between the central node and the peripheral nodes beyond that which is supported by the transmitter power of the central node or beyond that which is supported by the standard upon which the physical layer of the physical star network is based.
-
- Distributed Star
-
- Composed of individual networks that are based upon the physical star topology connected together in a linear fashion – i.e., ‘daisy-chained’ – with no central or top level connection point (e.g., two or more ’stacked’ hubs, along with their associated star connected nodes or ’spokes’).
Ring
Ring network topology
- In local area networks where the ring topology is used, each computer is connected to the network in a closed loop or ring. Each machine or computer has a unique address that is used for identification purposes. The signal passes through each machine or computer connected to the ring in one direction. Ring topologies typically utilize a token passing scheme, used to control access to the network.The primary disadvantage of ring topology is the failure of one machine will cause the entire network to fail.
- Mesh
- The value of fully meshed networks is proportional to the exponent of the number of subscribers, assuming that communicating groups of any two endpoints, up to and including all the endpoints, is approximated by Reed’s Law.
Fully connected mesh topology
- The nodes of the network is connected to each of the other nodes in the network with a point-to-point link – this makes it possible for data to be simultaneously transmitted from any single node to all of the other nodes.
Partially connected mesh topology
-
- The nodes of the network are connected to more than one other node in the network with a point-to-point link – this makes it possible to take advantage of some of the redundancy that is provided by a physical fully connected mesh topology without the expense and complexity required for a connection between every node in the network.
- Tree
Tree network topology
Also known as a hierarchical network.
-
-
The type of network topology in which a central ‘root’ node (the top level of the hierarchy) is connected to one or more other nodes that are one level lower in the hierarchy (i.e., the second level) with a point-to-point link between each of the second level nodes and the top level central ‘root’ node, while each of the second level nodes that are connected to the top level central ‘root’ node will also have one or more other nodes that are one level lower in the hierarchy (i.e., the third level) connected to it, also with a point-to-point link, the top level central ‘root’ node being the only node that has no other node above it in the hierarchy (The hierarchy of the tree is symmetrical.)
-
Signal topology
The mapping of the actual connections between the nodes of a network, as evidenced by the path that the signals take when propagating between the nodes.
- Note: The term ’signal topology’ is often used synonymously with the term ‘logical topology’, however, some confusion may result from this practice in certain situations since, by definition, the term ‘logical topology’ refers to the apparent path that the data takes between nodes in a network while the term ’signal topology’ generally refers to the actual path that the signals (e.g., optical, electrical, electromagnetic, etc.) take when propagating between nodes.
Logical topology
The logical topology, in contrast to the “physical”, is the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices. A network’s logical topology is not necessarily the same as its physical topology. For example, twisted pair Ethernet is a logical bus topology in a physical star topology layout. While IBM’s Token Ring is a logical ring topology, it is physically set up in a star topology.
Classification of logical topologies
The logical classification of network topologies generally follows the same classifications as those in the physical classifications of network topologies, the path that the data takes between nodes being used to determine the topology as opposed to the actual physical connections being used to determine the topology.
- Notes:
-
- 1.) Logical topologies are often closely associated with media access control (MAC) methods and protocols.
-
- 2.) The logical topologies are generally determined by network protocols as opposed to being determined by the physical layout of cables, wires, and network devices or by the flow of the electrical signals, although in many cases the paths that the electrical signals take between nodes may closely match the logical flow of data, hence the convention of using the terms ‘logical topology’ and ’signal topology’ interchangeably.
Daisy chains
Except for star-based networks, the easiest way to add more computers into a network is by daisy-chaining, or connecting each computer in series to the next. If a message is intended for a computer partway down the line, each system bounces it along in sequence until it reaches the destination. A daisy-chained network can take two basic forms: linear and ring.
- A linear topology puts a two-way link between one computer and the next. However, this was expensive in the early days of computing, since each computer (except for the ones at each end) required two receivers and two transmitters.
- By connecting the computers at each end, a ring topology can be formed. An advantage of the ring is that the number of transmitters and receivers can be cut in half, since a message will eventually loop all of the way around. When a node sends a message, the message is processed by each computer in the ring.
Centralization
The star topology reduces the probability of a network failure by connecting all of the peripheral nodes (computers, etc.) to a central node. When the physical star topology is applied to a logical bus network such as Ethernet, this central node (traditionally a hub) rebroadcasts all transmissions received from any peripheral node to all peripheral nodes on the network, sometimes including the originating node. All peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the central node only. The failure of a transmission line linking any peripheral node to the central node will result in the isolation of that peripheral node from all others, but the remaining peripheral nodes will be unaffected. However, the disadvantage is that the failure of the central node will cause the failure of all of the peripheral nodes also.
A tree topology (a.k.a. hierarchical topology) can be viewed as a collection of star networks arranged in a hierarchy. This tree has individual peripheral nodes (e.g. leaves) which are required to transmit to and receive from one other node only and are not required to act as repeaters or regenerators. Unlike the star network, the functionality of the central node may be distributed.
As in the conventional star network, individual nodes may thus still be isolated from the network by a single-point failure of a transmission path to the node. If a link connecting a leaf fails, that leaf is isolated; if a connection to a non-leaf node fails, an entire section of the network becomes isolated from the rest.
In order to alleviate the amount of network traffic that comes from broadcasting all signals to all nodes, more advanced central nodes were developed that are able to keep track of the identities of the nodes that are connected to the network. These network switches will “learn” the layout of the network by “listening” on each port during normal data transmission, examining the data packets and recording the address/identifier of each connected node and which port it’s connected to in a lookup table held in memory.
-
-
Decentralization
In a mesh topology (i.e., a partially connected mesh topology), there are at least two nodes with two or more paths between them to provide redundant paths to be used in case the link providing one of the paths fails. This decentralization is often used to advantage to compensate for the single-point-failure disadvantage that is present when using a single device as a central node (e.g., in star and tree networks). A special kind of mesh, limiting the number of hops between two nodes, is a hypercube. The number of arbitrary forks in mesh networks makes them more difficult to design and implement, but their decentralized nature makes them very useful. This is similar in some ways to a grid network, where a linear or ring topology is used to connect systems in multiple directions. A multi-dimensional ring has a toroidal topology, for instance.
A fully connected network, complete topology or full mesh topology is a network topology in which there is a direct link between all pairs of nodes. In a fully connected network with n nodes, there are n(n-1)/2 direct links. Networks designed with this topology are usually very expensive to set up, but provide a high degree of reliability due to the multiple paths for data that are provided by the large number of redundant links between nodes. This topology is mostly seen in military applications. However, it can also be seen in the file sharing protocol BitTorrent in which users connect to other users in the “swarm” by allowing each user sharing the file to connect to other users also involved.
-
Hybrids
A combination of any two or more topologies in such a way that the resulting network does not exhibit one of the standard topologies (e.g., bus, star, ring, etc.). For example, a tree network connected to a tree network is still a tree network, but two star networks connected together exhibit a hybrid network topology. A hybrid topology is always produced when two different basic network topologies are connected. Two common examples for Hybrid network are: star ring network and star bus network
- A Star ring network consists of two or more star topologies connected using a multistation access unit (MAU) as a centralized hub.
- A Star Bus network consists of two or more star topologies connected using a bus trunk (the bus trunk serves as the network’s backbone).
While grid networks have found popularity in high-performance computing applications, some systems have used genetic algorithms to design custom networks that have the fewest possible hops in between different nodes. Some of the resulting layouts are nearly incomprehensible, although they function quite well.
-
OPEN SOURCE
August 27, 2009 Open source Spreadsheet Gnumeric - is part of the GNOME desktop and has Windows installers available. It is intended to be a free replacement for proprietary spreadsheet programs such as Microsoft Excel, which it broadly and openly emulates. It has the ability to import and export data in several file formats, including CSV, Microsoft Excel, HTML, LaTeX, Lotus 1-2-3, OpenDocument and Quattro Pro; its native format is the Gnumeric file format (.gnm or .gnumeric), an XML file compressed with gzip. It includes all of the spreadsheet functions of the North American edition of Microsoft Excel and many functions unique to Gnumeric. Pivot tables and conditional formatting are not yet supported but are planned for future versions. GNU Oleo OPEN SOURCE PRESENTATION ‘’an effective presentation is one in which the audience finds the information useful and interesting and where fonts, colours, images and sound are used in ways that catch their attention and help to get the information across.’’ So, in setting a presentation as an activity, what is important? There seem to be a number of bases to cover here: · Research - exploring the subject, discerning what matters and being selective, analyzing, making comparisons, telling stories, organizing things into a structure. And, of course, the content itself does matter, and having 11 year olds spend the first six lessons of senior school ICT on producing a presentation to introduce themselves to their classmates seems a wasted opportunity, when so many aspects of other subject could be explored here. · Use of the software - there are skills to be learnt here, no matter how quickly learners pick up an interface: the example of PowerPoint’s outlining tool springs to mind, and yet, this is relatively low level stuff, we’re not, after all writing code here · Design - there’s a potential conflict here with the software skills, as it’s all too easy to focus on adding complexity and distractions when, I suspect, a really effective presentation, one that stands out from the crowd, has an elegant simplicity to its design. It’s possible that folk over in the art department might be better at teaching this than the ICT staff. · The actual presenting bit - again, something which ICT teachers might not be the best folk to teach: I’m thinking cross-curricular projects with drama, English, history whatever, might have some real value here, and this is one aspect which the ESB presentation element has certainly helped my pupils towards. · Reflection - feedback from the audience, including the teacher(s), time to reflect on how the presentation went and what’s been learnt. Of course, PowerPoint, when used well, isn’t going to stand in the way of achieving these objectives. That said, my ongoing exploration of ubuntu/edubuntu has provided some interesting insights into the world of presentation software that exists beyond PowerPoint. The most obvious alternative is OpenOffice Impress, which is, I’d say, a pretty good substitute for PowerPoint. It’s a pretty good substitute for the MS product, without quite so many transition, animation and clipart effects, which given my views above, may be no bad thing. The outline tool is good, although it doesn’t have the interoperability with Writer that Word/PowerPoint have. One of the best things about Impress is its export capabilities, with native support for Flash and PDF. Impress’s PDF export capabilities are particularly good when used alongside KeyJNote as a tool for viewing presentations. In the best traditions of Open Source, we have here a small program that does a single task very well, the task in this case being showing presentation slides - lots of command line or sidecar file based options, but in essence it provides eye-candy transitions, text and mouse highlighting, and a quick overview feature to use whilst running the presentation. Really nice software, which will work with directories of image files too. The Windows and Linux versions don’t even need installing (although the Linux one needs Python to work), making them ideal for storing on a USB stick alongside the presentation slides themselves. The PDF export from Impress is also useful in conjunction with SuperShow, which will combine the slides from the pdf with audio recorded alongside and output a .swf file of the whole presentation. I have a lot of admiration for LyX’s WYSIWYM approach to document creation, although I’ve not yet managed to give up the bad habits of messing with formats acquired through using Word. Using the LaTeX Beamer class, LyX is quite capable of producing some rather elegant presentation slides, which again feed beautifully into KeyJNote. I’m not convinced that this quite has the ease of use I’m looking for for primary work, but it does keep the focus very much on the content and the structure. Elgg itself now has a presentation module, and whilst it’s not a bad way to share presentation content online, I can’t imagine many folk using it live with an audience: it’s probably best used as an e-portfolio tool, as Helen Barrett is. Something like slideshare or GoogleApps’s long expected presentation tool is, I suspect, a more transparent way of publishing traditional slides. The social network dimension of these web-based applications has much going for it in terms of my reflection objective above: slideshare do seem to have got this right. Indeed, just as Flickr is a great resource for teaching photography, Slideshare would be a pretty good tool for teaching about presentation design. Alas, unlike gallery2 as an alternative to Flickr, I’m not aware of any open-source version which one could run inside a walled garden… There are other interesting ways of using the web for presentations though. Eric Meyer’s S5 is particularly impressive, although I’d be hesitant before going down the route of teaching the mark-up needed to primary children. S5 integration into Moodle and Elgg would be avenues worth exploring. Another cool idea is the XUL based tool that bright-green developed for Takahashi style minimalist presentations. The research aspect that is a key part of presentation work in school as I see it is perhaps best achieved outside of the presentation software itself. Google notebook might be a starting point here, but of course, it’s not open source. For web-based research, del.icio.us has much to be said, and clever use of tagging would allow for some content organization on the fly, together with some interesting possibilities for collaborative research. There is a whole host of open source applications which replicate del.icou.us’s functionality, and in some cases API, such as scuttle. A wiki would also provide a way to collect source material together, and with a little organization, editing, and design work, could also be used for the presentation itself. An alternative approach, and one I’ve used successfully in the past, is to use mind mapping software such as freemind or semantik for this, and I think this provides a visual, accessible route in to the crucial sifting and organization dimension. There are interesting interoperabilities here: semantik (nee kdissert) is designed as an authoring / outlining tool, and will happily produce Beamer formatted LaTeX, Freemind, on the other hand, has mediawiki and del.icio.us integration, both of which are very cool, although the wiki browser doesn’t appear to be GPLed In fact, Freemind’s non-linear, strongly visual format would, if we weren’t so wedded to the linear format of the PowerPoint presentation, make it a very appealing tool for illustrating a presentation - certainly worth experimenting with, I think. Alternative approaches to presentations are undoubtedly of value. Much could be done using images alone, such as in iphoto or photostory: linux has SlideshowCreator, but the interface is a bit OTT; there may be others out there! I have a vivid recollection of Stephen Heppell presenting by just talking us through a number of pictures, documents, webpages etc that he’d gathered together in a folder on his PowerBook. There’s also something to be said for dispensing with the slideware entirely, and just talking to and interacting with the audience. If you’re like most PC users, the word processor is one of your own most mission-critical applications. On the Linux side, the OpenOffice.org Writer word processing program has garnered a lot of attention lately, partly due to the inclusion of the OpenOffice.org suite on high-profile netbooks. But literally dozens of other word processing applications are also out there for Linux, and some of these are lighter in weight, suiting them to possible use on either a netbook, an embedded device, or that old legacy PC sitting around in your storage area. Last week, in the first installment of our series of articles on word processors for Linux, we took a look at five of the best known open source offerings: OpenOffice.org; an alternative full-featured word processor dubbed AbiWord; and three offerings honed for specialized purposes: KWord, LYX, and e:doc. Now we’re moving on to five more entries in the open source Linux category. EZ Writer is the grand-daddy of them all. The other four on this week’s list–Ted, FLWriter, WordGrinder, and EZ Word–all hold relative smallness and sleekness as their main claims to fame. In contrast to so-called proprietary word processors for Linux–StarOffice and the much newer ThinkFree, for example–these open source applications are free software programs that will cost you zilch. Ted OS Platforms: Linux and other Unix OS. If you buy a new Linux netbook such as the Dell Inspiron Mini 10 or HP Mini 100 Mi Edition, it will come with OpenOffice.org Write. Meanwhile, Chinese vendor HiVision last fall released a $98 Linux netbook outfitted with AbiWord. But some users prefer lighter word processors–either to save space, to gain speedier performance, or simply because they don’t want or need a lot of fancy capabilities. While Ted is smaller than either Write or AbiWord, it’s still strong on features, ease of use, and compatibility with Microsoft Word. Developed by Mark de Does, the multingual program actually started out as a text editor–more along the lines of Microsoft WordPad than Word. In response to user feedback, de Does has then fixed bugs and added more capabilities along the way. Ted comes with a built-in spell checker, but this function won’t annoy you by spelling as you type. Other current features include text alignment, multiple fonts, and support for headers, footers, and tables. You can also find and replace text, spice up your document with paragraph borders and shading, and insert pictures, hyperlinks, and bookmarks, for instance. While Ted doesn’t run on Windows, it’s expressly designed to achieve as much compatibility with Windows as possible. You can save documents in the Windows .RTF format for later use on Windows systems. Ted can also be configured to read formatted e-mail sent from a Windows machine to Linux or Unix. Along with source code licensed under the General Public License (GPL), binary files packaged in RPM and tar.gz files are also available for Ted. The binaries are statically linked with the Motif libraries, meaning that you don’t need to install these proprietary libraries in order to run the word processing program. FLWriter OS Platforms: Linux and other Unix OS. In the name FLWriter, the letter “F” stands for “Fast,” whereas “L” is for “Light.” Regardless of the initial intent, however, this small what-you-see-is-what-you-get (WYSIWYG) word processor hasn’t seen any further development–or very much use–in several years. It’s now being usurped by rivals. In an indication of FLWriter’s decline, the Damned Small Linux (DSL) project dropped the program from its distribution in favor of the fuller-featured Ted way back in 2006. The last version of FLWriter was only released in XD640, a now practically defunct project to build a desktop environment at 640-by-480 resolution for legacy PCs. FLWriter uses UTF-8 XHTML as its native file format. That format, however, has since been merged into the FTLK library, so that a separate library is no longer necessary if you still wish to try out the program. WordGrinder OS Platforms: Linux, other Unix OS, Windows, and OS X. Now in beta, WordGrinder has recently enjoyed some copious open source development from members of the Puppy Linux community, for example. WordGrinder is emphatically not a WYSIWYG word processor, according to its creator, David Given. “It is not point and click. It is not desktop publisher. It is not a text editor. It [does] not do fonts and it barely does styles. It’s designed for writing text. It gets out of your way and let you type,” Given writes in the online documentation. Consisting of only 6,300 lines of code, the tiny program DOES offer Unicode character support; an intuitive menu system; fast-access keyboard shortcuts configurable from within WordGrinder; a certain amount of character and style support; HTML import and export; and LATEX and Troff export. Pathetic Writer OS Platforms: Linux and other flavors of Unix. Pathetic Writer is part of the long-time Siag Office suite, together with the Siag spreadsheet, Egon animation program, Xfiler file manager; Sed Plus text editor; and Gvu, a PostScript document viewer. On its own, Pathetic Writer is a simple but rather complete word processor, supporting functions such as styles, selectable fonts, simple formatting, and column and row sorting. Its Toolbar offers icons for things like opening a file and saving a document, yet many other functions are still command-driven. However, this X-based word processor offers big benefits in terms of customizability (if you know what you’re doing with that, at least.) People conversant with programming lantuages such as Scheme, Ruby, Python, Guild, or Tcl can easily built extensions that let them make Pathetic Writer do exactly what they’d like it to do. Pathetic Writer supports RTF for file exchange with Microsoft Word. Moreover, external converters such as Carolan McNamara’s WV can be used for reading documents from a wide range of outside programs, While PW is copyrighted by its creator, Ulrick Eriksson, it’s available for use by anyone free of charge. EZ Word OS Platforms: Linux and additional Unix variants. EZ Word is less likely than a lot of other word processors to get installed on any type of PC these days. But it’s good to know about, anyhow, from a historical standpoint. Originally devised as part of the Andrew User Interface System (AUIS), a user-interface research project conducted by IBM with Carnegie Mellon University, EZ Word was the very first graphical word processor to become available for Linux. Despite its name, though, EZ Word was never easy for most folks to use. If you didn’t climb EZ Word’s learning curve more than a decade ago, you probably won’t want to start now. Although still available under a BSD free sofware license, the program hasn’t been updated since the release of version 8.0 in 1997, and bugs still linger. Open Source Database Apache Derby, an Apache DB subproject, is an open source relational database implemented entirely in Java and available under the Apache License, Version 2.0. Some key advantages include:
It’s accuracy has helped it to establish a niche among people using it for statistical analysis and other scientific tasks. For improving the accuracy of Gnumeric, the developers are cooperating with the R Project.
- is a lightweight free software spreadsheet software package. Oleo was originally designed as a text-based spreadsheet (using the curses library).
It is much older than the GNU Gnumeric spreadsheet (a part of the GNOME desktop system) and has fewer capabilities. It is also not as active as a project, not having had a release since 2001.
KSpread
KSpread is part of KOffice, an integrated office suite for the KDE Desktop Environment.
Among KSpread features are multiple sheets per document, assorted formatting possibilities, support for more than 100 built-in functions, templates, chart, spell-check, hyperlinks, data sorting and scripting with Python, Ruby and Javascript.
It’s native format is XML, compressed with ZIP. However, KSpread has the ability to import in several spreadsheet formats, including Microsoft Excel, Applix Spreadsheet, Quattro Pro, CSV and OpenOffice.org Calc.
OpenOffice.org Calc
- is a component of the OpenOffice.org software package. It is similar to Microsoft Excel, with a roughly equivalent range of features. Calc is capable of opening and saving spreadsheets in Microsoft Excel file format. It provides a number of features not present in Excel, including a system which automatically defines series for graphing based on the layout of the user’s data. Calc is also capable of writing spreadsheets directly as PDF files.
The default file format for OpenOffice.org 2.0 Calc can be set to either Microsoft Excel or the OASIS Open Document Format (ODF). Calc also supports a wide range of other file formats, for both opening and saving files.
As with the entire OpenOffice.org suite, Calc can be used across a variety of platforms, including Mac OS X, Microsoft Windows, Linux, FreeBSD and Solaris. Available under the GNU Lesser General Public License, Calc is free software.
SIAG
SIAG (Scheme in a grid) is a spreadsheet using a SIOD engine or base. The grid, siag is fast and very configurable. Suitable for small unix distributions, it was selected by DSL to provide a spreadsheet inside their fifty megabyte system footprint. Consequently, siag can be used on older PCs with their limited memory and disk space.
Language modules for C, SIOD, Guile, Python, Ruby, Tcl, etc. permit extensive control over input and output data. Any unix shell can further script siag grids to display cells in algorithmic form.
Simple Spreadsheet
Simple Spreadsheet is a web-based spreadsheet program written in JavaScript, HTML, CSS and PHP. It features formulas, charts, formats, cell/row merging, cell locking, keyboard navigation, etc. Simple Spreadsheet is released under the GNU General Public License, and is thus free software.
Custom macros can be written in Javascript. Javascript is also used as the default (human-readable) data format. Future versions will contain collaborative features to allow many people working simultaneously together on one sheet. The charts are generated on the server-side using a PHP library called JpGraph. On the client side they are referenced with a function inside a formula.
Simple Spreadsheet can be used with all common browsers like Firefox, Opera, Konqueror, and Internet Explorer. Safari may be used, but was not yet tested.
wikiCalc
wikiCalc is a web application, created by Dan Bricklin, that allows for the creation and editing of spreadsheets through a wiki-style user-editable interface. It is currently released as version 1.0 for use on Windows, Mac, Linux/Unix, and other platforms that can run the Perl language.
The product was envisioned in 2005 by Bricklin, who 27 years earlier created VisiCalc, the first commercial spreadsheet program for the personal computer. Version Alpha 0.1 was released for alpha testing in November 2005. Version 1.0 was released on January 25, 2007. wikiCalc is written in the Perl programming language.
.
* Derby has a small footprint — about 2 megabytes for the base engine and embedded JDBC driver.
* Derby is based on the Java, JDBC, and SQL standards.
* Derby provides an embedded JDBC driver that lets you embed Derby in any Java-based solution.
* Derby also supports the more familiar client/server mode with the Derby Network Client JDBC driver and Derby Network Server.
* Derby is easy to install, deploy, and use.
| Berkeley DB JE is a high performance, transactional storage engine written entirely in Java. Like the highly successful Berkeley DB product, Berkeley DB JE executes in the address space of the application, without the overhead of client/server communication. It stores data in the application’s native format, so no runtime data translation is required. Berkeley DB JE supports full ACID transactions and recovery. It provides an easy-to-use interface, allowing programmers to store and retrieve information quickly, simply and reliably. Berkeley DB JE was designed from the ground up in Java. It takes full advantage of the Java environment. The Berkeley DB JE API provides a Java Collections-style interface, as well as a programmatic interface similar to the Berkeley DB API. The architecture of Berkeley DB JE supports high performance and concurrency for both read-intensive and write-intensive workloads. Berkeley DB JE is different from all other Java databases available today. Berkeley DB JE is not a relational engine built in Java. It is a Berkeley DB-style embedded store, with an interface designed for programmers, not DBAs. Berkeley DB JE’s architecture employs a log-based, no-overwrite storage system, enabling high concurrency and speed while providing ACID transactions and record-level locking. Berkeley DB JE efficiently caches most commonly used data in memory, without exceeding application-specified limits. In this way Berkeley DB JE works with an application to use available JVM resources while providing access to very large data sets. |
Go To Berkeley DB Java Edition
| hsqldb is a relational database engine written in Java, with a JDBC driver, supporting a rich subset of ANSI-92 SQL (BNF tree format). It offers a small (less than 160k), fast database engine which offers both in memory and disk based tables. Embedded and server modes are available. Additionally, it includes tools such as a minimal web server, in-memory query and management tools (can be run as applets) and a number of demonstration examples. |
| Axion is a small, fast, open source relational database system (RDBMS) supporting SQL and JDBC written in and for the Java programming language. |
| db4o (database for objects) is the open source object database for Java. Features include: fast native Java object persistence, ACID transactions, query-by-example, S.O.D.A. object query API, automatic class schema recognition, small footprint. |
| The Ozone Database Project is a open initiative for the creation of an open source, Java based, object-oriented database management system. Ozone includes a fully W3C compliant DOM implementation that allows you to store XML data. You can use any XML tool to provide and access these data. Support classes for Apache Xerces-J and Xalan-J are included. |
| NeoDatis ODB is a new generation Object Oriented Database. ODB is a real transparent persistence layer that allows anyone to persist native objects with a single line of code. ODB can be used as an embedded database engine that can be seamlessly integrated to any product as an embedded database or in client/server mode. |
| Mckoi SQL Database is optimized to run as a client/server database server for multiple clients, however it can also be embedded in an application as a stand-alone database. It is highly multi-threaded and features an extendable object-oriented engine. |
| H2 is a SQL database engine written in Java. JDBC and ODBC drivers, embedded and client/server mode. Clustering is supported. In-memory and disk based tables. A web console application is included. |
| Perst is an object-oriented embedded database for Java and .NET applications that need to deal with persistent data. It is easy to use and provides high performance. Although Perst is very simple, it provides fault-tolerant support (ACID transactions) and concurrent access to the database. The main advantage of Perst is its tight integration with programming languages. |
| Ashpool is a lightweight XML Database written in Java(tm). It’s goal is to use standard SQL92 syntax to query, add, update, and delete XML documents via a JDBC driver. The XML documents must hold to a table like structure. The reason for the table structure restriction is that SQL was designed to query table data not hierarchical data. |
| One$DB is a version of Daffodil DB , a J2EE-certified, JDBC 3.0 and SQL-99 compliant Java database. It is available in both Network and Embedded editions and has been designed to handle complex computing environments that demand a robust, scalable and feature-rich RDBMS that can operate across platforms. |
| Neo4j is a graph database. It is an embedded, disk-based, fully transactional Java persistence engine that stores data structured in graphs rather than in tables. A graph (mathematical lingo for a network) is a flexible data structure that allows a more agile and rapid style of development. |
| SmallSQL is a 100% pure Java DBMS, a relational database for Java desktop applications. It has a JDBC 3.0 interface and offering many ANSI SQL 92 and ANSI SQL 99 features. It is very small and fast because it does not have a network interface. |
| Jalisto is a lightweight transactional database written entirely in Java. Jalisto comes in two versions: Jalisto SE (Standard Edition) and Jalisto ME (Micro Edition). Jalisto SE is an ideal solution for embedded and stand-alone systems. Jalisto ME, which will be available in Q4, targets mobile environments including cell phones, PDAs, and is compatible with the Java 2 Platform Micro Edition (J2ME). |
| QED, the Quadcap Embeddable Database. QED is a fast, small, pure Java, relational database, implementing the SQL 92 standard, with transactions and resilient failure recovery. QED has a novel open source license permitting free use of QED by all and free redistribution in other open source projects. |
Go To Quadcap Embeddable Database
| A very lightweight 100% Java text SQL engine that includes a JDBC driver |
| JDBC Driver for the spreadsheets Excel, StarOffice and OpenOffice. Turn a directory with spreadsheets into a database. xls filenames become database schema’s, sheets become tables. Use a rich subset of SQL to create sheets and query sheets. Join sheets, query database data and store it into excel or fill database tables with spreadsheets. |
| MyOODB (My Object-Oriented Database) is an integrated database and Web environment that provides true distributed objects, implicit/explicit multi-concurrent nested transactions, seamless Web tunneling, and database self-healing. MyOODB is one part of a two part SDK solution. Together with MyOOWEB, MyOOSDK provides a development environment for people who desire small, fast, but powerful applications. |
| A 100% pure Java, lightweight, single file embeddable database. Functionally similar to a cross between SQLite and BerkeleyDB. Developed for use with PDA and Mobile applications. |
| JODB (Java Objects Database) is an open source object-oriented database. The database uses a cache based on Soft References to avoid using too much memory when the application requires it. The queries are optimized to use the minimal possible object instantiations during the search to avoid excessive garbage collection. |
| AcornDB is a high performance, small footprint, transactional object oriented database written entirely in Java. It stores data in the application’s native format, so no runtime data translation is required. AcornDB supports full ACID transactions and recovery. It provides an easy-to-use interface like query-by-example, object query API, automatic class schema recognition allowing programmers to store and retrieve information quickly, simply and reliably. AcornDB enabling high concurrency and speed while providing ACID transactions. AcornDB efficiently caches the data in memory, without exceeding application-specified limits. In this way works with an application to use available JVM resources while providing access to very large data sets. |
| The yaRDBMS (yet another relational database management system) is a Java based, transactional highly concurrent relational database management system with advanced query optimization, indexing features and crash recovery. |
| jiql is a Java database for Cloud computing. The database is accessed via a jdbc client. The data is actually stored in a cloud-based data store, such as Google’s BigTable. The fact is Google App Engine at present only supports python. Java programmers need not be excluded, as jiql provides a way to at least utilize Google’s BigTable. By uploading the jiql python controller (jiql.py) to Google App Engine (GAE), the jiql.py acts as a gateway between the jiql database engine and Google’s BigTable (GBT). So a Java application, using standard JDBC calls to the jiql JDBC client, is able to store critical data in GBT. As the DataStore sits in the cloud, you essentially have a solution for distributed database access. Thus, although you may not be able to host a JAVA program on GAE, you can still use the Data Store, which is probably the most important aspect of cloud-computing - that is scalability and high availability. |
my midterm
August 17, 2009Women, Justice and Peace and Integrity of Creation (WJPIC) Thrust- The direction that propels the Province to carry out our charism and mission given the W-JPIC Perspective.
W-JPIC Perspective:
II. based on analysis of economic, social, political, cultural, gender and ecological structures in society that can either be life-giving or death-dealing
III. enriched and challenged by reflections in the light of our faith (which includes scriptural and congregational) heritage
IV. flowing (“daluyan”) into a commitment towards transformative actions, responses and way of life
V. integrating celebrations through creative liturgies and rituals, acts of reconciliation and reparation
It is a Perspective which after being borne of a critical analysis of an experience oppression, relating with an understanding of the roots of the problems of our society and challenged by our faith and culture commits us to transform whatever is oppressive and death-dealing towards liberative and life-giving actions and responses eventually celebrating the awareness of the New Paradigm!
Operational Definition of Terms:
Women
a. Recognition of their dignity, equality, rights and contribution to development and to society
b. No discrimination because of their gender, class, race, entity and caste
c. Greater appreciation of the role of women as givers and nurtures of life in their present context of destruction of human life and nature
d. Empowerment in all levels/aspects
Justice
§ What is due a person-balance of rights and relationships
§ respects for and the promotion of the bacic rights and services necessary for the existence of all beings (including creatures’ rights)
§ right relationships between people, between people and creation, etc.
§ efforts to build constructive and liberating relationships
§ shift from the human-centered worldview to the web of life worldview
§ Fundamental equality of all persons
§ Promotion and the defense of rights of all beings
§ Acts of solidarity with the poor, oppressed, deprived and exploited
§ Common Good
§ Inclusion vs. Exclusion, Marginalization
§ Acts of hospitality to the stranger, the scared child, the beaten down women, the enthusiastic youth group, the co-worker who needs talk etc.
Peace
1. The fruit if Justice
2. Intercultural understanding
3. Interfaith, Interreligious Dialogue
4. Acts of Justice:signature-campaign, lobbying, petitions, perspective in non-violence, in words and in thoughts, to live conscientiously and simply in order not to do wrong anyone
Integrity of Creation
ü Growing awareness of environment concerns
ü Just and mutual relationships between human beings and the environment
ü Well-being of the universe/earth is primary; the well-being of humanity is derivative
ü Sustainable Future/Sustainability of the Planet Earth
Humans are not separate, over and above earth. Earth with all subsystems of land, water, air, plants, animals and humans is one web of life.
History Of Computer
July 16, 2009450 bc
Stones and pebbles-introduced by the Greek as “counting aids” and will return in this form as a means to count similar to an Abacus (around 50 bc) in the Roman Empire. It spread through Europe.In Western Europe these counting boards stay in use for a pretty long time but gradually one starts to use the indo-Arabic notation of numbers: “0123456789″. (+/- 1200).
Muhammed idn Musa Al-Khwarizmi - born in 780 A.D. and died in 850 A.D. He was an Arabic mathematician who introduced the Hindu decimal system and the use of zero into Arabic mathematics. He also extended the work of Diophantis on algebraic equations in a book, the title which included the word al-jabr (transposition) from which the modern word algebra is derived.
1594
Lord John Napier (1550-1617) -from Merchiston (Scotland), thought to practice black arts. Develops the Natural Logarithm (ln). He also invents a kind of mechanical calculator the famous Napier Bones and writes about it in his Rabdologica. Now it was rather simple to multiply. His best known implement however is or are the so called “bones” this is an aid to multiplication. But maybe the chessboard calculator is the most ingenious and least known. |
1726
Jonathan Swift (England) -describes a machine that writes books automatically in: Gulliver’s Travels. A revolutionary idea that even in the 21st century is not yet fully realized.
1727
Antonius Braun (Austria) -develops in this year the first calculator with the four basis calculations: add - subtract - multiply and divide.
1822Charles Babbage -designs a calculator. It should be operated by punched cards (see Jacquard 1801) and the results printed on paper.
|
Mechanical (tolerances), financial (subsidies) and differences of opinion with his chief engineer - Joseph Clement a tool engineer and draftsman, a rare combination in these days - are causing the project to be shelved in 1833. But the concept of the machine is of course extremely advanced and probably too far out of most peoples league for this days to even think about. Or let alone conceptualize.
In 1990-1991 Reg Crick en Barry Holliday - two engineers of the Science museum in London - will reconstruct the calculating section of the Difference Engine.
1834
It was at this point, 1834, that Babbage had an idea for a completely different machine — one that would operate more rapidly and have far more extensive powers than the Difference Engine.
For basic elements are:
- Input unit
- The ALU or Algorithmic Unit
- Central controller
- Output unit
With his experience with the difference engine he knows that to build a machine like that the funding must come from his private funds. He succeeds in building a small model of the Analytical Engine.They had spent 17,000 pounds with nothing to show.
1886
Herman Hollerith (USA) -constructs the first “electro mechanical adding and sorting machine”. He wins the contest and his machine will be used with the census in 1890. The machine is ready with the data processing one whole year before anything done by hand would have been ready. Off course this establishes the fame of automation and people become convinced of the speed and accuracy of machines like that. Hollerith will found Tabulating and Recording Company. This company, with other mergers as well, will become the IBM company.
IBM is officially founded from the Computing Tabulating Recording Company.
Search
| M | T | W | T | F | S | S |
|---|---|---|---|---|---|---|
| « Oct | ||||||
| 1 | 2 | 3 | 4 | |||
| 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| 26 | 27 | 28 | 29 | 30 | 31 | |
Monthly Archives
Sponsored Links
Tag Cloud
About Me
Most Popular
- Types of Topology (280)
- OPEN SOURCE (133)
- PrinsEsa (86)
- History Of Computer (36)
- my midterm (26)
Recent Photo
Message Board
- Procure:
I’ve only spent a short amount of time in Manila but I really must say it’s an amazing area. But anyway, I just wanted to stop by because I’m researching blogs about the Philippines and found your site on yahoo. If you have any ideas on things to try while here in the Philippines then I’d appreciate hearing them
- support:
Congratulations, you’ve just completed the installation of this shoutbox.
- support:
Hi! Your shoutbox is working fine!