Free predictive programing software for linux

GNU Archimedes is the GNU package for the design and simulation of submicron semiconductor devices. Archimedes is a 2D Fast Monte Carlo simulator which can take into account all the relevant quantum effects, thank to the implementation of the Bohm effective potential method.

The physics and geometry of a general device is introduced by typing a simple script, which makes, in this sense, GNU Archimedes a powerfull tool for the simulation of quite general semiconductor devices.

In the present release, GNU Archimedes is able to simulate electrons and heavy holes in Silicon and GaAs (Gamma and L-valleys) devices (holes are simulated by means of a simplified MEP model), and in the next release, which is in preparation, it will be able to make simulations in 1D, 2D and 3D (this release will be delivered as soon as possible).

The Scientifical and Industrial Motivations
In today semiconductor technology, the miniaturization of devices is more and more progressing. In this context, it is easy to see that numerical simulations play an important role at every level of device manufacture. In fact, the cost of designing and physically constructing prototypes for VLSI semiconductor devices is very high and without the availability of advanced simulators the efforts for devices miniaturization would, likely, be brought to a halt. From assessing the performance of individual transistors, to circuits and systems, and, consequently, with the promise of improved device performance, industries are encouraged to keep on miniaturizing with lower manufacture costs.

But, unfortunately, such simulations are not whithout their challenges... A first consequence of device miniaturization is that simulations of submicron semicondutor devices requires advanced transport models. Because of the presence of very high and rapidly varying electric field, phenomena occur which cannot be described by means of the well-known drift-diffusion models, which do not incorporate energy as a dynamical variable.

That is why some generalization has been sought in order to obtain more physically accurate models, like energy-transport and hydrodynamical models. The energy-transport models which are implemented in commercial simulators are based on phenomenological constitutive equations for the particle flux and energy flux depending on a set of parameters which are fitted to homogeneous bulk material Monte Carlo simulations. So, this is not, certainly, a satisfactory physical description of the internal electronic dynamics in a semiconductor device.

As current device technologies quickly approach the scales whereby quantum effects due to strong confinement of carriers and direct source-drain tunneling will begin to dominate, new simulation techniques are required in order to fully understand and acurately simulate the physics behind the technology operation.

Of all the simulation methods currently employed, ensemble Monte Carlo has always been, both in the accademic and industrial community, the most vigorous and trusted method for device simulation, as it is proven to be reliable and predictive, as one can easily see from the vast bibliography on this subject.

However, as Monte Carlo relies on the particle nature of the electron (in fact we consider an electron like a biliard ball), quantum effects associated with the wave-like nature of electrons cannot fully incorporated into the actual simulators, i.e. the ensemble Monte Carlo have to be lightly (or strongly, it depends on the point of view and on the methods implemented...) modified to take into account the quantum effects, at least at a first order of approximation, which is certainly enough to take into account correctly all the relevant quantum effects present in the present-day semiconductor devices (till 2015 probably...). In order to take into account the wave-like nature of electrons we use a recently introduced quantum theory, the so-called Bohm effective potential theory.

So it is challenging and very interesting to develop such a code for 2D quantum submicron semiconductor devices. This is why I have decided to implement this code, but these are not the only motivations...

The Ethical Motivations
The very sad situation you quickly observe working in a semiconductor industry, but also in all places in which researches about semiconductor devices are made, the only codes for simulation you can find are not free and are proprietary codes.

That is a very bad situation because, at the present time, if you need to develop your own code for the purpose of simulating a device it is IMPOSSIBLE to obtain an advanced one in a short time, and, trust me, this is EXTREMELY BAD for scientific research... (Immagine if you had to re-discover the Newtonian laws every time you need them...) So, you can find a huge amount of papers describing a lot of numerical methods for simulating, in a very advanced way, semiconductor devices (even in the quantum case), but nobody will give you a code on which you can construct your own method (with the unlikely exception that at least one of the programmers is a friend of yours :) ).

Even worst, if you are a semiconductor device designer and you want to simulate "realistically" a new device, you have to pay (trust me, at very high costs!) a BINARY (just a binary and not the code!) from some well-known software industry. This binary will certainly have some bugs (because it is coded by humans which are not perfect...) and you will never have the possibility of fix them on your own. Of course, you can write to the software house and tell them that there is a bug, but, how many time do you will wait for a new release without those bugs? I dont think it will be a short time...

My impression is that, after a long research on the Web for a Free Software dealing with advanced 2D semiconductor device simulation, there was not a free code for the purpose of semiconductor devices simulation (i mean under GPL license). To be sure about it, I asked to the great Richard Stallman (by mail) if it will be worth to do a code like this and he encouraged me to code it, because there wasnt a code like this as free. So I decided to write this code..

KXplayer is a very simple media player, based on xine. Its my hobby-project - just a way to get a better knowledge of KDEs internals.

Besides I wanted to learn programming C++ and since I believe the best way to learn programing is to write a program, I just made my mind to write a multimedia player.

Since it is a player, this word had to be in present in the title. The K and X appered there because of KDE (interface) and XINE (backend).

I took the decision to write a player because I needed one. I needed a good media player for KDE (something like XMMS with KDE inderface), which would be working as reliably as possible.

At present my PC is a 750MHz Duron with 128MB RAM and its almost imposible to work in OpenOffice.org and listen to MP3/OGG at the same time. Running XMMS and OpenOffice 1.x together on my Mandrake results in sound fragmentation.

For some time Ive been using boombox (you can find it in kde-apps). It is based on xine and I found it working better than xmms - almost no fragmentation. Unfortunately boomboxs interface is a bit strange (IMHO) and its not saving the equalizer settings (very annoying).

Aeromys is a webmail application designed for extremely fast access to email through the web. An interesting feature of the aplication is that it caches the messages from the server before user requested it.
I had the idea for Aeromys several years ago when I was thinking about how PHP was essentially an inappropriate technology for writing a web application. I like to make the distinction between a web site, and a web application. A web site is what you are looking at right now, it displays information and can be navigated. It is by nature in page-form. However, an application is different. It takes much more processing and more overhead. This is the problem I saw with most web applications written in PHP. They were slow, not because of a flaw in their design or poor implementation, but simply because of the nature of HTTP and PHP.
As I got to thinking about it, I realized that the application server model is much more appropriate. Application servers have been in use for quite a while, they are not a new or novel concept. However, as Ill show later, some of the things Im trying to do with Aeromys are new to the webmail domain, and are pretty exciting.
Another inherent problem with using PHP for web applications is that there is a lot of down time. PHP can only run after a user has requested a page. That is, Apache will spawn the PHP process, parse the PHP script, and execute it. All this time, the user is waiting on the other end. Delays of even a second are noticed. In a webmail application, these kind of delays are common because the PHP process must connect out to the IMAP server, which takes time.
Enter Aeromys. Aeromys has a webmail daemon (webmaild) that is constantly running in the background. This daemon keeps track of the users who have logged into the system and keeps their IMAP connections alive between page loads. Also, while the user is reading his or her email, this daemon takes advantage of the down time and pre-fetches information that it thinks will be requested for the next page load. This is what I call "predictive caching." When the user makes the next page request, hopefully the information required for building that page will have already been cached and can be displayed instantly.
This semester (Spring 2005), I am working on Aeromys as an independant study project under Dr. Peter Wurman at North Carolina State University in Raleigh, NC. It is my hope to continue this work on through as my masters thesis and possibly a doctoral dissertation. So I have a personal vested interest in this project.
Enhancements:
- Added basic sorting method
- Switched back-end libraries from c-client to libEtPan
- Improved interactive mode
- Improved logging and debugging capabilities
- Fixed several crash bugs

JGachine project is a Java game machine/engine/browser.
JGachine is a networked game engine for 2D multi-player (networked) games.
It is written in Java and C++.
The games themselves are written in pure Java and can be loaded via the network.
Main features:
- easy game programing for beginners
- a game machine/engine/browser
- one client for multiple games
- you only write the game server (though the server may send bytecode to the client)
- secure client (though executing bytecode from the server
- writing multiplayer networked games within 2 hours
- portable
- try to allow output device independent games
- device independent coordinates
- help with different/changing aspect ratios

Audio::Data is a module for representing audio data to perl.

SYNOPSIS

use Audio::Data;
my $audio = Audio::Data->new(rate => , ...);

$audio->method(...)

$audio OP ...

Audio::Data represents audio data to perl in a fairly compact and efficient manner using C via XS to hold data as a C array of float values. The use of float avoids many issues with dynamic range, and typical float has 24-bit mantissa so quantization noise should be acceptable. Many machines have floating point hardware these days, and in such cases operations on float should be as fast or faster than some kind of "scaled integer".

Nominally data is expected to be between +1.0 and -1.0 - although only code which interacts with outside world (reading/writing files or devices) really cares.
It can also represent elements (samples) which are "complex numbers" which simplifies many Digital Signal Processing methods.

Methods

The interface is object-oriented, and provides the methods below.
$audio = Audio::Data->new([method => value ...])
The "constructor" - takes a list of method/value pairs and calls $audio->method(value) on the object in order. Typically first "method" will be rate to set sampling rate of the object.

$rate = $audio->rate
Get sampling rate of object.
$audio->rate($newrate)
Set sampling rate of the object. If object contains existing data it is re-sampled to the new rate. (Code to do this was derived from a now dated version of sox.)
$audio->comment($string)
Sets simple string comment associated with data.
$string = $audio->comment
Get the comment
$time = $audio->duration
Return duration of object (in seconds).
$time = $audio->samples
Return number of samples in the object.
@data = $audio->data
Return data as list of values - not recommended for large data.
$audio->data(@data)
Sets elements from @data.
$audio->length($N)
Set number of samples to $N - tuncating or padding with zeros (silence).
($max,$min) = $audio->bounds([$start_time[,$end_time]])
Returns a list of two values representing the limits of the values between the two times if $end_time isnt specified it defaults to the duration of the object, and if start time isnt specified it defaults to zero.
$copy = $audio->clone
Creates copy of data carrying over sample rate and complex-ness of data.
$slice = $audio->timerange($start_time,$end_time);
Returns a time-slice between specified times.
$audio->Load($fh)
Reads Sun/NeXT .au data from the perl file handle (which should have binmode() applied to it.)
This will eventually change - to allow it to load other formats and perhaps to return list of Audio::Data objects to represnt multiple channels (e.g. stereo).
$audio->Save($fh[,$comment])
Write a Sun/NeXT .au file to perl file handle. $comment if specified is used as the comment.
$audio->tone($freq,$dur,$amp);
Append a sinusoidal tone of specified freqency (in Hz) and duration (in seconds), and peak amplitude $amp.
$audio->silence($dur);
Append a period of 0 value of specified duration.
$audio->noise($dur,$amp);
Append burst of (white) noise of specified duration and peak amplitude.
$window = $audio->hamming($SIZE,$start_sample[,$k])
Returns a "raised cosine window" sample of $SIZE samples starting at specified sample. If $k is specified it overrides the default value of 0.46 (e.g. a value of 0.5 would give a Hanning window as opposed to a Hamming window.)
windowed = ((1.0-k)+k*cos(x*PI))
$freq = $audio->fft($SIZE)
$time = $freq->ifft($SIZE);
Perform a Fast Fourier Transform (or its inverse). (Note that in general result of these methods have complex numbers as the elements. $SIZE should be a power-of-two (if it isnt next larger power of two is used). Data is padded with zeros as necessary to get to $SIZE samples.
@values = $audio->amplitude([$N[,$count]])
Return values of amplitude for sample $N..$N+$count inclusive. if $N is not specified it defaults to zero. If $count is not specified it defaults to 1 for scalar context and rest-of-data in array context.
@values = $audio->dB([$N[,$count]])
Return amplitude - in deci-Bells. (0dB is 1/2**15 i.e. least detectable value to 16-bit device.) Defaults as for amplitude.
@values = $audio->phase([$N [,$count]])
Return Phase - (if data are real returns 0). Defaults as for amplitude.
$diff = $audio->difference
Returns the first difference between successive elements of the data - so result is one sample shorter. This is a simple high-pass filter and is much used to remove DC offsets.
$Avalues = $audio->lpc($NUM_POLES,[$auto [,$refl]])
Perform Linear Predictive Coding analysis of $audio and return coefficents of resulting All-Pole filter. 0th Element is not a filter coefficent (there is no A[0] in such a filter) - but is a measure of the "error" in the matching process. $auto is an output argument and returns computed autocorrelation. $refl is also output and are so-called reflection coefficents used in "lattice" realization of the filter. (Code for this lifted from "Festival" speech systems speech_tools.)
$auto = $audio->autocorrelation($LENGTH)
Returns an (unscaled) autocorrelation function - can be used to cause peaks when data is periodic - and is used as a precursor to LPC analysis.

phpWebApp is an application framework which makes easy and simple the task of building PHP web applications based on relational databases. It separates the task of designing and changing the layout of the application from the task of implementing the logic of the application, by using XML templates that are an extension of XHTML.
The project also simplifies the task of implementing the logic of the application by offering an event based programming model. In addition, phpWebApp tries to offer modularity and code reusability to the community of webApp developers.
Main features:
- The framework separates the layout from the logic of the application, so a graphical designer can easily improve the layout of the application without getting messed with the logic and without having to understand it. It makes easier the work of both the graphical designer and the programer. This also facilitates an iterative and incremental development approach for web application projects.
- The framework gives the possibility to divide a page into several parts which can be used in other pages as well. This makes the user interface of the application (the layout, the graphical part) more structured and easier to understand and maintain and makes easier the work of the graphical designer.
- The framework looks at web applications from a new point of view. From this point of view, a web application is a state machine, which can be represented and described by one or more statechart diagrams. Each page of the application that is displayed, represents the application in a certain state. Clicking to a link causes a transition to another state of the application. This simplifies the design and the implementation of web applications. Later, if this point of view is formalised and elaborated enough, it may provide the theoretical bases for automatic code generation of web applications from state chart diagrams (e.g. from UML state chart diagrams), and for reverse engineering.
- The framework supports an event based programing model. When a transition from one state of the application to another happens, it may trigger an event as well, which is handled by a function (event handler). This makes the logic of the application easy to build, understand and maintain, and makes easy the work of the web programer.
- The framework gives to the web programers the possibility to create independent web components (called WebBox-es) which have their own user interface (graphical design), client side behaviour, server side behaviour, states, events, event handlers, etc. These components can be very easily reused in other web applications and thus provide code reusability to web programers. This means that if you have constructed something once, you dont have to re-construct it again when you need it another time, but use it ready.
- The framework brings closer the client-side and the server-side logic of a web application. E.g. the session variables (which are usually used to keep the state of various parts of the application), are available and can be accessed both on client side and on server side.
- The framework makes the interaction with the database almost database independent. This means that in case that you decide to change the database on which your application is based (e.g. switching from MySQL to Oracle), then the application itself doesnt need to be changed at all, it will work all the same.
Enhancements:
- Bugfixes and some improvements in documentation were made.

Test::STDmaker is a Perl module to generate test scripts, demo scripts from a test description short hand.

SYNOPSIS

#######
# Procedural (subroutine) interface
#
use Test::STDmake qw(find_t_roots get_data perl_command);

@t_path = find_t_paths()
$date = get_date();
$myperl = perl_command();

#####
# Class interface
#
use Test::STDmaker

$std = new Test::STDmaker( @options ); # From File::Maker

$success = $std->check_db($std_pm);
@t_path = $std->find_t_paths()
$date = $std->get_date();
$myperl = $std->perl_command();

$std->tmake( @targets, %options );
$std->tmake( @targets );
$std->tmake( %options );

######
# Internal (Private) Methods
#
$success = $std->build($std_driver_class);
$success = $std->generate();
$success = $std->print($file_out);

The Test::STDmaker program module provides the following capabilities:
Automate Perl related programming needed to create a test script resulting in reduction of time and cost.

Translate a short hand Software Test Description (STD) file into a Perl test script that eventually makes use of the Test module.

Translate the sort hand STD data file into a Perl demo script that demonstrates the features of the the module under test.

Provide in the POD of a STD file information required by a Military/Federal Government Software Test Description (STD) document that may easily be index and accessed by automated Test software. ISO, British Military require most of the same information, US agencies such as the FAA. The difference is that ISO, British Military do not dictate detail format. US agencies such as FAA will generally tailor down the DOD required formats.

Thus, there is an extremely wide variation in the format of the same information among ISO certified comericial activities and militaries other than US. Once the information is in a POD, different translators may format nearly exactly as dictated by the end user, whether it is the US DOD, ISO certified commericial activity, British Military or whoever. By being able to provide the most demanding, which is usually US DOD, the capabilities are there for all the others.

The Test::STDmaker package relieves the designer and developer from the burden of filling out word processor boiler plate templates (whether run-off, Word, or vi), counting oks, providing documentation examples, tracing tests to test requirments, making sure it is in the proper corporate, ISO or military format, and other such extremely time consuming, boring, development support tasks. Instead the designers and developers need only to fill in a form using a test description short hand. The Test::STDmaker will take it from there and automatically and quickly generate the desired test scripts, demo scripts, and test description documents.

Look at the economics. It does not make economically sense to have expensive talent do this work. In does not even make economically sense to take a bright 16 year, at mimimum wage and have him manually count oks. Perl can count those oks much much cheaper and it is so easily to automated with Perl. And something like this were you are doing it year in and year out, the saving are enormous. To a program manager or contract officer, this is what programming and computers are all about, saving money and increasing productivity, not object oriented oriented programing, gotos or other such things.

The Test::STDmaker class package automates the generation of Software Test Descriptions (STD) Plain Old Documentation (POD), test scripts, demonstrations scripts and the execution of the generated test scripts and demonstration scripts. It will automatically insert the output from the demonstration script into the POD -headx Demonstration section of the file being tested.