Статті в журналах з теми "UNIX FORTRAN (Computer program language)"

Computer programming has been used effectively by theoretical chemists and organic chemists to solve various types of problem in chemistry. Initially the languages used for computations in chemistry were FORTRAN and BASIC. Later the Pascal language was used for solving problems in chemistry and physics. Recently the languages C and C++ and Java have been used to solve problems in chemistry. In this paper I will illustrate features of C, C++ choosing examples from chemistry. Computer programming has been used effectively by theoretical chemists and organic chemists to solve various types of problem in chemistry. Initially the languages used for computations in chemistry were FORTRAN and BASIC. Later the Pascal language was used for solving problems in chemistry and physics. Recently the languages C and C++ and Java have been used to solve problems in chemistry. In this paper I will illustrate features of C, C++ choosing examples from chemistry. Some examples presented in this these languages are Program to calculate reduced mass of homo diatomic or hetero diatomic Program to calculate the molecular weight of a tetra atomic system ABCD Program to calculate NMR frequencies of spin 1/2 nuclei only Program to calculate NMR and ESR frequencies The examples presented in Java 2 are Program to calculate unit cell dimension of a crystal Program to generate the chair form and boat form of cyclohexane. The examples presented in this monograph will help researchers in theoretical chemistry and organic chemistry to develop their own software.

Abstract The efficiency of D4 Gaussian elimination on a vector computer, the Cray- 1/S, it examined. The algorithm used in this work is employed routinely in Phillips Petroleum Co. reservoir simulation models. Comparisons of scalar Phillips Petroleum Co. reservoir simulation models. Comparisons of scalar and vector Cray-1/S times are given for various example cases including multiple unknowns per gridblock. Vectorization of the program on the Cray- 1/S is discussed. Introduction In reservoir simulation, the solution of large systems of linear equations accounts for a substantial percentage of the computation time. Methods used today consist of both iterative and direct solution algorithms. Because of the theoretical savings in both storage and computing labor, D4 Gaussian elimination is a popular direct solution algorithm and is used widely on conventional scalar computers. In this paper we investigate the efficiency of the D4 algorithm on a computer with vector processing capabilities-the Cray-1/S. The D4 (or alternate diagonal) algorithm originally was presented by Price and Coats in 1973. Since that time much work has been done on the Price and Coats in 1973. Since that time much work has been done on the algorithm including an investigation by Nolen on the vector performance of D4 on the CDC Star 100 and Cyber 203 on single-unknown-per-gridblock example cases. Levesque has presented a comparison of the Cray-1 and Cyber 205 in reservoir simulation that includes the D4 algorithm. Vector performance of the Cray-1 on linear algebra kernels, both sparse and dense, performance of the Cray-1 on linear algebra kernels, both sparse and dense, also has been reported. Vector performance on these kernels typically is expressed in terms of million floating point operations per second (MFLOPS). Our objective here is to evaluate vector performance on a typical production code written in FORTRAN for a scalar computer. Therefore, performance, or efficiency, will be evaluated in terms of both scalar and vector CPU times on the Cray-1/S. We include vector performance on the original code with automatic vectorization enabled, and vector performance on the same code with minor restructuring, automatic performance on the same code with minor restructuring, automatic vectorization enabled, and the use of Cray assembly language (CAL) basic linear algebra kernels. Example cases for multiple unknowns per gridblock are presented. Reservoir Flow Equations The reservoir flow equations written using a seven-point finite difference formulation can be expressed as ...........................(1) where the terms A, B... G are matrices of order N equal to the number of unknowns per gridblock. represents the vector of unknowns at cell i, j, k, and H is the vector of residuals of the flow equations at cell i, j, k at iteration . Values of N from 1 to 10 typically are encountered depending on the type of simulator and the degree of implicitness used. For example, N is equal to one for an implicit pressure, explicit saturation (IMPES) black-oil model; three for a fully implicit black-oil model; five for an implicit three-component steamflood model and usually 10 or less for an implicit compositional model. Driver Program To facilitate timing studies in this work, a driver program was written to calculate coefficients for the D4 Gaussian elimination routine. Input to the program consists of grid dimensions and the number of unknowns per gridblock. All elements of the off-diagonal matrices (A, C, D... G) were set equal to 1. To guarantee a nonsingular solution, the B matrix was set equal to -5 for one unknown and as below for N unknowns. ............................(2) Right-side coefficients, H, were calculated by assuming a unit solution for . No-flow boundary conditions were used, which require specific matrices, such as A for I = 1 and C for I = NX, to be set equal to zero. Description of Hardware and Software All run times reported in this work were obtained on the Cray-1/S, Serial No. 23, at United Computing Systems in Kansas City, MO. Serial No. 23 contains 1 million 64-bit words of central memory interleaved in 16 memory banks and no input/output (I/O) subsystems. The FORTRAN compiler used was CFT 1.09. CPU times were obtained by calling SECOND, a FORTRAN-callable utility routine that returns CPU time since the start of the job in FPS'S. CPU overhead incurred for each call to SECOND is approximately 2.5 microseconds. For all reported Cray-1/S times, "vector" refers to the original FORTRAN code run with automatic vectorization enabled, which is the normal operating mode. SPEJ p. 121

NRCVAX is a complete system of programs, covering all aspects of crystal structure analysis from data reduction to the presentation of results. The system, which is written in a `neutral' Fortran 77, presently exists in two forms. The first runs on a VAX computer under VMS, on an 80386 PC under UNIX and under IBM VM/CMS and MVS/TSO. The second is an adaptation which runs on PC-XT, AT, PS/2 and comparable microcomputers under MS-DOS. The two versions differ somewhat in structure, but very little in code, operation or functionality except for the graphics. The many options of the programs can be selected in a highly interactive manner and because of this the system is very flexible. Most options are assigned default values, however, and it is usually safe to run the routines with a minimum of user input using the defaults. The system will accept data from a wide variety of sources and has interface routines for several other systems. Graphics in the VAX/UNIX version are based on the widely available Tektronix 4000 series protocol, while the microcomputer version supports most common display adapters. It is also possible to prepare files for a variety of plotters, dot-matrix printers and laser printers. Source code is distributed and it should not be difficult to adapt the system to any computer with virtual memory and a Fortran 77 compiler.

Cold startup of boiler is the process of boiler operation with water at ambient temperature and pressure with all intake and discharge valves are fully closed to permit fast development of pressure. A mathematical model is developed to estimate the pressure response during cold startup of a perfectly insulated steam generator unit. A commercial type pressure switch is used in this unit to control and maintain the desired set point of the steam operating pressure. This mathematical model assume that the thermal properties of the supplied liquid water are temperature dependent. It is based on a novel Pressure Marching Technique that is coded using a FORTRAN language computer program. The maximum percentage error of (8.24 %) was obtained when comparing the predicted results of the mathematical model with the measured values obtained from the experimental test that was done using a (2 kW) electric steam generator unit with a volume of (30 litter) and maximum operating pressure of (8 bar). In addition, the same behavior of the predicted results was obtained when compared with results of a previously published article. It was found that the time constant of the pressure control system is directly proportional with its operating pressure set point and with the volume of the steam generator and its void fraction. A (50%) increase in the pressure set point will increase the time constant by (66.16%). Increasing the boiler volume by (166.667%) will increase the time constant by (166.677%) and increasing the boiler void fraction by (150%) will increase the time constant by (23.634%). The time constant is inversely proportional with the heating power of the steam generator. A (100%) increase in the heating power will decrease the time constant by (50%). The time constant is independent of the initial water temperature. Also, it was found that the time delay to start water evaporation is directly proportional with the volume of the steam generator. A (166.667%) increase in boiler volume will increase the time delay by (166.65%). The time delay is inversely proportional with the initial water temperature and with the heating power and void fraction of the steam generator. A (38.889%) increase in the initial water temperature will decrease the time delay by (8.882%). Increasing the heating power by (100%) will decrease the time delay by (50%) and increasing the boiler void fraction by (150%) will decrease the time delay by (16.665%). The time delay is independent on the operating pressure set point.

This paper presents Mustang, a system that automatically parallellizes Fortran programs by mapping them to single assignment semantics. Specifically, sequential Fortran source programs are translated into IF1, a machine-independent dataflow graph description language that is the intermediate form for the SISAL language. During this translation, Parfrase 2 is used to parse the source program perform dependency analysis and to detect opportunities for parallelization which are then explicitly introduced into the IF1 program. The resulting IF1 program is then processed by the Optimizing SISAL Compiler which produces parallel executables on multiple target platforms. A working prototype has been developed and tested. The execution results of several Livermore Loops are presented and compared against Fortran and SISAL implementations on two different platforms. The initial results obtained provide proof of concept that Fortran can be mapped to Single Assignment Semantics without sacrificing efficiency.

A method whereby a parameter optimization program, written in FORTRAN, can be used in conjunction with ACSL (Advanced Continuous Simulation Language) models of dynamic systems is described. The optimization of a projectile's trajectory is used as an example.

A Livermore Physics Applications Language (ALPAL), a new computer language, is described. ALPAL is a tool that generates a Fortran code module from a natural description of a physics model. This capability gives the computational physicist a significant productivity boost. While ALPAL is a working computer program, significant additions are being made to it. Some of the factors that make ALPAL an important tool are: first, it eliminates many sources of errors; second, it permits building program modules with far greater speed than is otherwise possible; third, it provides a means of specifying many numerical algorithms; and fourth, it is a language that is close to a journal-style presentation of physics models and numerical methods for solving them. In sum, ALPAL is designed to magnify the abilities and creativity of computational physicists.

This paper is written as a tutorial on how to use a one-dimensional map derived from Chua's circuit to study the circuit's complicated dynamics. While the derivation of this 1-D map is nontrivial, a user-friendly program is presented to help the beginner uncover and witness, without any prior background on chaos, numerous periodic, homoclinic, heteroclinic and chaotic orbits. In keeping with the pedagogical nature of this paper, these bifurcation phenomena will be profusely illustrated with pictures generated from a computer program, along with the exact parameters so that the reader can easily duplicate them. The program is written in the C-language for both PC-486 computers and UNIX workstations, and available upon requests from the Nonlinear Electronic Laboratory in Berkeley.

Reviewed the various constitutive mode of concrete faced rock-fill dam. Basis on the complex physical characteristic of filled the material and the framework of dam, a method of computer is given, introduced into the program of the concrete face rock-fill dam calculation with FORTRAN language on the ANSYS software. It is used to simulate two and three-dimensional nonlinear computation and compute figure simulation in the construction procedure and operation period for the concrete face rock fill dam, the result was intuitionist clarity.

A new computer program has been developed to convert electron probe microanalysis data into accurate measurements of chemical composition. It is menu-based and designed to operate off-line using any IBM PC compatible computer. As shown in the flowchart, fig. 1, the architecture is modular and the programming language adopted is a compilable version of BASIC which possesses much of the processing speed associated with FORTRAN or C. Specimens containing up to fifteen elements, with 4 ≤ Z ≤ 96, can be handled and all the major x-ray lines (Kα, Kβ, Lα, L(β, Mα and Mβ) are available for analysis purposes.The procedure itself is based upon the classical ZAF approach in which corrections for atomic number (Z), x-ray absorption (A), characteristic fluorescence (Fl) and continuum fluorescence (F2) are treated independently. The factors dealing with fluorescence are essentially those of Reed (characteristic) and Springer (continuum) although both contain minor updates. However, the atomic number and absorption factors are the authors' own and the latter, developed from a quadrilateral representation of the x-ray distribution with depth in a solid, distinguishes this program from others.

In this study, a computer program for calculating fatigue life of component is developed and introduced in LS-PrePost software. The program is written in Fortran programming language and the fatigue life equations used is taken from well-published literature. The materials covered are steel and aluminum. The developed program is able to read stress, strain and element values from d3plot and the keyword file. Having extracted the output from d3plot and keyword file, the fatigue life is then calculated and presented into a separate file called FATIGUE. The integration of output from FATIGUE will is displayed in LS-PrePost. Finally, the results of fatigue life contour are successfully displayed through LS-PrePost.

ABSTRACT As early as 1961 Mattessich suggested (in an article in The Accounting Review) to use budget simulation in form of a computerized spreadsheet. This was followed up by him in a mathematical model, outlined in his book Accounting and Analytical Methods (Mattessich 1964a) with a corresponding computer program (in FORTRAN IV on mainframe computers), including illustrations in a companion volume (Simulation of the Firm through a Budget Computer Program, Mattessich 1964b). Five years later (in 1969) Rene Pardo and Remy Landau co-presented “LANPAR” (LANguage for Programming Arrays at Random) at Random Corporation. This electronic spreadsheet type was also used on mainframe computers for budgeting at Bell Canada, AT&T, Bell operating companies, and General Motors. In 1978, Dan Bricklin and Robert Frankston introduced VisiCalc, the first commercialized spreadsheet program for personal desktop (Apple) computers. This program became the trailblazer for future developments of electronic spreadsheets.

As the progress of theory and computer technology, nonlinear analysis is widely applied in civil engineering. Strip method, as one of the numerical methods, is used widely especially in the analysis of beams, columns and shell structures. The first half of this paper introduces the theoretical model and the basic assumptions of the strip method; the latter half of this paper compiles the strip method into computer program using FORTRAN language. At last, using beams with rectangular cross-section of reinforced concrete structures as an example, the paper analyze the factors, such as the strength of the steel bars, which have an impact on the bearing capacity of reinforced concrete structures.

Based on the use of homogeneous transformation matrices with Denavit-Hartenberg notation and the Lagrangian formulation method, a general computer program ROBDYN.RED for the symbolic derivation of dynamic equations of motion for robot manipulators has been developed and is discussed in this paper. The program is developed by using REDUCE, an algebraic manipulation language, and is versatile for open-chain structure robot manipulators with any number of degrees of freedom and with any combination of types of joint. Considerations are also given to saving computer memory space required for execution and to minimizing the runtime. Several examples are included to demonstrate the use of the program. Equations of motion in scalar form can be automatically transferred to FORTRAN format for later numerical simulations. The efficiency of the resulting equations in terms of numerical integration is also discussed and some further developments to improve the efficiency are suggested.

The task of developing and implementing a software application for creating, editing, displaying on the screen, as well as saving in the form of files of various formats, which in turn will be used in programming in languages such as C, C++, Python, and the Linux system language – Bash, is being considered. The developed software application is designed to enable the user to interact with files of various extensions, edit and save changes, work with the content of files for further development of software code in languages such as C, C++, Python. The software application can be used both as a console application and with the use of a graphical interface on UNIX and MS Windows operating systems. During development, the UNIX operating system was used, namely the Linux – Ubuntu distribution, which made it possible to use the created text editor on such operating systems as Ubuntu, Linux Mint, Kali Linux, Raspberry Pi Ubuntu. A free cross–platform multimedia package of libraries – SFML was also used, which made it possible to use a text editor on the MS Windows platform. The source code of the SFML library is provided under the ZLIB/PNG Free Software Distribution License. During development, a method of processing input information, as well as saving it in a file of a separate format, was defined and implemented. The following programming languages were used: C, C++11, a convenient software application architecture was developed, which allows you to easily maintain and improve the program in the future. The use of a virtual machine was an integral part of the project. By using a virtual machine, many computer resources are utilized, such as: RAM, number of cores, data storage and discrete desktop acceleration in the desired operating system. A friendly graphical interface for user interaction has been implemented.

This paper presents the BONDYN program (BONd graph DYNamics) as a procedure for simulating dynamic systems. It is based on bond graph theory and provides a means for treating dynamic systems that simultaneously include various physical domains. The program makes use of the bond graph module handling facility in order to build a general model starting from simple submodels. Although the latter can be defined by the user, a library has been appended to the preprocessor which includes some of these submodels. Special developments for simulating multibody systems can be found among them. Once the overall bond graph has been assembled the program builds the state equations of the system in the form of a subroutine that can be accepted by a high level language compiler, which is FORTRAN 77 in this case. Simulation outputs can be shown either graphically or in a table.

The present work involves integration of the simulation stage of design of a VLSI circuit and its testing stage. The SPICE simulator, TEK LV500 ASIC Design Verification System, and TekWaves, a test program generator for LV500, were integrated. A software interface in ‘C’ language in UNIX ‘solaris 1.x’ environment has been developed between SPICE and the testing tools (TekWAVES and LV500). The function of the software interface developed is multifold. It takes input from either SPICE2G.6 or SPICE 3e.1. The output generated by the interface software can be given as an input to either TekWAVES or LV500. A graphical user interface has also been developed with OPENWlNDOWS using Xview tool kit on SUN workstation. As an example, a two phase clock generator circuit has been considered and usefulness of the software demonstrated. The interface software could be easily linked with VLSI design such as MAGIC layout editor.

The recent commercial introduction of the parallel detection electron energy-loss spectrometer has undoubtedly made electron energy-loss spectroscopy (EELS) more viable as a technique for routine microanalysis. Additionally, the increased recording efficiency of parallel EELS (PEELS) warrants the use of more involved acquisition and processing techniques than was necessary, or even possible with serial EELS. This increased complexity places greater demands on the computer systems controlling data acquisition. Multichannel analyzers systems with small resources and limited programming facilities are not capable of exploiting the full capabilities of the PEELS spectrometer.Preliminary efforts of the author with the Gatan PEELS spectrometer were concentrated on development of a flexible acquisition system at National Institutes of Health. Hardware control is performed through machine-language drivers called from high-level languages (HLL) such as FORTRAN and C. The software drivers and hardware were designed to minimize processor involvement in the data collection process, resulting in the capability to collect data while processing continues within the parent HLL. This design simplifies the HLL program structure and minimizes data collection dead time.

This paper puts forward a new mathematical model, which is a coal damage-heat-fluid-solid multi-field coupling theory, in order to reveal the mechanical mechanism of the increase of coal-bed methane recovery through thermal stimulation, and to evaluate its effect. The strain field is introduced to define the damage of coal by considering of the effects of temperature, gas pressure, and mining stress of the coal seam. It is used to quantitatively describe the degree of coal rupture and damage. Additionally, the elastic and damage constitutive equation of coal and rock mass, the governing equation of the temperature field, and the coupling equation of gas diffusion and seepage are established. Based on these equations, the finite element source program is redeveloped by using the FORTRAN language, and a multi-field coupling analysis program is compiled. This program takes the temperature, the gas seepage, and the damage and deformation of coal and rock mass into consideration. The effect of heat injection temperature on gas production efficiency, gas pressure distribution, and effective extraction radius during coal-bed methane mining process is analyzed. The results show that the injection of heat can significantly improve the desorption and diffusion of gas, as well as the gas production rate and the production efficiency of coal-bed methane.

Purpose.The task of researching modes of established frictional oscillations of the braking mechanism is to find a solution to the initial dynamic problem with friction that satisfies the periodicity conditions. At the same time, the period of motion of the dynamic system is not known in advance. This dynamic system is described by a non-linear dissipative non-autonomous system of differential equations. The methods. The developed technique of spectral analysis of the braking mechanism's oscillations is based on the assumption that its movements are periodic. If deterministic chaos occurs in the analyzed dynamic system, then the autocorrelation function of the time series of movements must have a finite carrier, that is, vanish outside a finite time interval. Findings. In the paper, the method of computational experiment is used to identify and study the characteristics of oscillatory processes in brake mechanisms. At the first stage of the computational experiment, a numerical solution of the considered dynamic problem with friction is carried out using a computational algorithm. As a result, the time series of block movements are calculated. At the second stage of the computational experiment, the obtained time series are studied. The originality. The paper uses phase diagrams in the "displacement-velocity" variables to analyze the process of establishing the oscillations of the brake mechanism and visual detection of attractors. When studying the dependence of amplitudes of displacements, velocities and accelerations of the dynamic system under consideration on changes in its parameters, the method of continuation by parameter was used with a stepwise change in the parameters of the system. Practical implementation. The developed mathematical model of vibrations of the braking mechanism and the computational algorithm for its numerical study are implemented in the form of a computer program for personal computers in the FORTRAN algorithmic language. Almost all available commercial compilers can be used to compile the program, including Compaq Visual Fortran 6.6 and Intel Visual Fortran 10, as well as non-commercial compilers distributed under the GNU license.

This paper describes the development of a dynamic model for the thermal-hydraulic analysis of MTR research reactors during a reactivity insertion accident. The model is formulated for coupling reactor kinetics with feedback reactivity and reactor core thermal-hydraulics. To represent the reactor core, two types of channels are considered, average and hot channels. The developed computer program is compiled and executed on a personal computer, using the FORTRAN language. The model is validated by safety-related benchmark calculations for MTR-TYPE reactors of IAEA 10 MW generic reactor for both slow and fast reactivity insertion transients. A good agreement is shown between the present model and the benchmark calculations. Then, the model is used for simulating the uncontrolled withdrawal of a control rod of an ETRR-2 reactor in transient with over power scram trip. The model results for ETRR-2 are analyzed and discussed.

The processing of dielectric materials in the radio frequency field continues to be a concern in engineering. This procedure involves a rigorous analysis of the electromagnetic field based on specific numerical methods. This paper presents an original method for analysing the process of drying wooden boards in a radio frequency (RF) installation. The electromagnetic field and thermal field are calculated using the finite element method (FEM). The load capacity of the installation is also calculated, since the material being heated in the radio frequency heating installations is placed in a capacitor-type applicator. A specific method is created in order to solve the problem related to mass, a quantity which tends to change during the drying of the dielectric. In addition, special consideration is given to issues regarding the coupling of the electromagnetic field and the thermal field, along with aspects pertaining to mass. These are implemented numerically using a program written in the Fortran language, which takes the distribution of finite elements from the Flux2D program, the dielectric thermal module, intended only for the study of RF heating. The results obtained after running the program are satisfactory and they represent a support for future studies, especially if the movement of the dielectric is taken into account.

This paper reports a method of thermal analysis of expressway and the results of analysis of four expressways currently used in Japan. The authors built a mathematical model based on the principle of thermal conduction. For the boundary conditions in this mathematical model the influence of solar radiation, wind and air temperature etc. are taken into consideration. Explicit finite difference method is used in the analysis. The authors made an analysis program in Fortran language. Four main expressways distributing from the northern to the southern in Japan are chosen as the objects of this study. The observed weather data of the hottest days experienced by these expressways during the past 30 years is input into the computer calculation. The basic mechanism of expressway temperature change and effect factors are illuminated. The results are reported and discussed.

This article presents results obtained from a research into an application of simulated annealing method to the in-core fuel reloading pattern optimization for a research reactor. The decision variable of the optimization problem is a fuel reloading pattern for the next cycle after the present cycle finishes. The objective function maximizes the effective multiplication factor keff at the beginning of cycle while it is established to include an important safety paramater – the power peaking factor, in search process. A procedure for searching the optimal solutions was formed and a computer code was developed in the Fortran language running on PCs. Nuclear safety parameters for the optimization problem are provided from the results of the multigroup neutron diffusion theory computation program CITATION. A sample calculation was performed to find the optimal fuel reloading patterns for the second cycle of the Dalat research reactor and the results are presented in this article.

Python is a relatively new computing language, created by Guido van Rossum [A.S. Tanenbaum, R. van Renesse, H. van Staveren, G.J. Sharp, S.J. Mullender, A.J. Jansen, G. van Rossum, Experiences with the Amoeba distributed operating system, Communications of the ACM 33 (1990) 46–63; also on-line at http://www.cs.vu.nl/pub/amoeba/, which is particularly suitable for teaching a course in computational physics. There are two questions to be considered: (i) For whom is the course intended? (ii) What are the criteria for a suitable language, and why choose Python? The criteria include the nature of the application. High performance computing requires a compiled language, e.g., FORTRAN. For some applications a computer algebra, e.g., Maple, is appropriate. For teaching, and for program development, an interpreted language has considerable advantages: Python appears particularly suitable. Python‟s attractions include (i) its system of modules which makes it easy to extend, (ii) its excellent graphics (VPython module), (iii) its excellent on line documentation, (iv) it is free and can be downloaded from the web. Python and VPython will be described briefly, and some programs demonstrated numerical and animation of some phenomenal physics. In this article, we gave solution of circle polarization by solving Maxwell equation.

Presented in this paper is a series of bending moment influence surfaces for concrete rectangular plates simply supported at three edges and built-in at the fourth edge. The solutions are obtained analytically on the basis of thin plate's theory with small deflection using double Fourier series. The influence surfaces are presented for two observation points namely the center of the plate as well as the midpoint of the built-in edge. A computer program was written in FORTRAN language to generate the influence surfaces making use of the developed analytical solutions of this work. The validity of the computer solution was confirmed by comparing its results with published results for zero Poisson's ratio and excellent agreement was obtained. An application of the influence surfaces for the case of a line load as well as a strip load is also presented.The paper reveals that the bending moment influence surfaces depend on the actual value of Poisson's ratio, aspect ratio of the plate, and position of the observation point.

One of the objectives of this study is to elaborate an engine cycle simulation program in FORTRAN language to analyze the influence of operating parameters on the performance (theeffective power, torque and specific fuel consumption) of a four-stroke gasoline engine (Ford ZSG 416 gasoline engine) for different engine operating parameters. The GT-Powerengine simulation software was used to compare the results obtained with the developed computer program and to improve it. In this program, a single-zone thermodynamicmodel was considered, which describes each phase of the engine cycle. In order to validate the developed program, a comparison of the experimental results with those obtainedusing GT-Power software was carried out. The other objective of this paper is to investigate the influence of a number of significant engine parameters such as compression ratio, cylinder wall temperature, cylinder diameter, stroke-bore ratio and ignition angle on the performance of the chosen engine. Examining the experimental results and those obtained with the developed program, it was observed that the power difference was in the order of ± 3%, the torque difference was ± 6%, while the BSFC difference was about ± 10%. It has been noted that the most significant parameters in improving the performance of the gasoline engine are the compression ratio, the fuel/air ratio, the engine geometry and the ignition begin. The variation of these parameters was not arbitrary, the knock criteria, in other words, the achievement of normal combustion were taken into account.

Static Analysis (SA) is the practice of examining computer program source code for errors or vulnerabilities outside the compiler’s capabilities. To carry out Static Analysis on computer programs, various tools exist that parse and examine each line for known issues. These tools do not compile the program, nor do they run the program. Instead, they analyse the source code directly and infer properties about the program without executing it - thus “static” analysis. Static analysis is not new. Early UNIX contained a program called “lint” for static analysis; a tool that has now existed since the late 1970s (Johnson 1978). Increasingly, however, modern static analysis practices indicate a more focused intent; find cybersecurity weaknesses. At the 22nd European Conference on Cyber Warfare and Security, the authors presented the background of Intermediate Representations (IRs) and described how this “middleware” representation can be utilized for static analysis of source code for cybersecurity weaknesses. By examining an IR, potential flaws in the source code can be located. When utilizing the IR as opposed to the original high-level language, the static analysis process becomes independent of the original source language; if several languages such as C, Rust, and others all compile into the same IR, static analysis of the IR allows the analysis process to no longer be tied to the high-level language grammar or syntax. The previous paper implemented a literature survey of available IR analysis tools to discover prior work; the authors have subsequently advanced the research and are actively using an IR framework, LLVM, for vulnerability analysis. In this research, source code in a high-level language is first compiled to LLVM and the resulting IR is used for analysis. This approach uses a “code-to-IR” SA analysis preparation paradigm. At the same time, there is the potential for binary “lifters” to be used. These tools “lift” an executable program – binary machine instructions – back to LLVM. In this way, the paradigm can also be reversed such that static analysis of LLVM can be performed on source code compiled into LLVM, or on executable programs in the field that are “lifted”. This begs: how effective are these “lifters”? In this work, the authors present experiences in installation and operation of several binary “lifters” available as open-source projects. Some are supported better than others, some operate better than others, and some don’t operate at all. Those that do lead to the follow-up: Is the “lifted” code suitable for static analysis, or is it too obfuscated relative to the original program? This paper describes just that – our efforts and results in locating a binary “lifter” suitable for bringing executable program test cases back to LLVM for analysis by the cybersecurity vulnerability tool concurrently under development.

PIXE (Particle Induced X-ray Emission), mainly Proton Induced X-ray Emission, has been developed into a well established technique for elemental analysis, especially for trace elemental analysis down to ppm or even ppb level. Nuclear Microprobe is a quickly developing technique around the world for 2 dimensional or even 3 dimensional element analysis if several nuclear analytical techniques, such as Rutherford backscattering spectrometry (RBS) can be available at the same time. The present resolution of NMP can be down to less than 1μm. To thick target analysis, i.e., the energy loss effect and the consequent X-ray cross section Change with the depth can not be neglected, therefore we have to consider the process of particle interactions with atoms in detail. In this article, NMP (Nuclear Micro-Probe) and micro-PIXE analysis of thick target, which are mainly involved into the process of ions interaction with atoms, are reviewed on the basis of work what we have done at Fudan University. The software package TSPIXE (PIXE analysis of Thick Sample), which includes different versions for different applications, developed at Fudan University for quantitative analysis of thick target and simulation of PIXE and micro-PIXE spectra are described and its performance is demonstrated too. The TSPIXE package, which includes TSPIXE version I, version II, version III and TSμPIXE, was written in FORTRAN and C computer language and can be run at PC computer under MSDOS or WINDOWS environment. From the different demonstrations and applications we can see the package is very useful to quantitative analysis of thick samples and to understand the relationships between elemental X-ray intensity distributions and concentration distributions, sample structure, beam size and etc.

Fatigue is a phenomenon that appears in items subjected to cyclic loads. Thus, rupture and partial oxidation are initiated from the beginning of the process. For this, the study of such a problem of material in fracture mechanics is based on the numerical analysis of the characteristics of a crack. In this article, we propose a modelling of crack propagation by a new method of stretching the mesh by 2D finite element in mixed mode, based on the creation of the elements through a program in the computer language Fortran. The parametric mesh with 4 nodes (CPE4) was created to make the simulation and to characterise the stress intensity factors, by the Abaqus computer code. For this, the validation of stretching finite element method (SFEM) results is done by other methods: extended finite element method (XFEM) and analytical method to simulate the crack propagation. The stress intensity factor (SIF) is an essential parameter of this study. Two possibilities for determining the SIF have been retained: one by the numerical method of our choice and the other by the analytical method. Parameters to characterise the stress state at the crack front KI and KII were evaluated in two stages one by the crack length and the other by the a/c ratio.

A simulation model consists of equations that represent the important relationships between components in a system, e.g., a plant or plant part. One of the purposes of simulation models is to simulate plant growth or plant growth processes to help further our understanding of plant growth and development. Simulation models are mechanistic or process based models that account for the physiological processes occurring in the system.Model development involves several steps. We define the problem and defuse the system, its entities, their attributes, and important relationships. A conceptual model is often expressed visually in a relational diagram showing the components and their relationships. This diagram is formally expressed as a simulation model through the use of equations repenting the relationships in the system. We often make assumptions regarding the components and their relationships to simply the model or because of a lack of knowledge. Simulation models are generally written using a simulation language such as CSMP or STELLA® or with a programming language such as FORTRAN or BASIC. The model is verified through checking the appropriateness of the relationships and the integrity of the computer program. The model is then validated through seeing bow well it simulates the behavior of the system. Simulation models provide additional insights by enabling us to ask “What if” questions by changing of the conditions of the model and seeing the resulting changes in plant growth.

The development of parameterized modeling for ST8075 tower crane is based on finite element analysis software SAP84 and high-level programming language Fortran. According to the Saint-Venant principle, the special beam elements such as rotation joint and connection knots are specially reinforced if they don’t affect force analysis and deformation analysis of the whole structure. The tower crane is built into many small modules, which include balance arms, booms, tower body and so on. The developed program for the tower crane can realize the following functions: inputting the following parameters such as the tower body standard joint number, the boom combination type, working amplitude and hoisting weight, the computer can automatically generate hoisting points and get required crane with any tower body standard joints and booms’ combination type. According to inputted boom combination type and amplitude, the program will automatically judge the balance weight value applied to the balance arm, apply the balance weight, assure the variable-amplitude vehicle’s position, apply the hoisting load, apply the hanger weight and generate data files. It can calculate tower crane’s force state when the crane is working at various working case such as working state and storm case. After calculating the crane, inner forces can be checked and judged whether the beams meet the requirements of strength, stiffness and stability. It is easy to optimize the product design, reduce the crane’s potential risks and raise its safety assurance. It has important significance for research and development of new products.

Shatt Al-Hilla was considered one of the important branches of Euphrates River that supplies irrigation water to millions of dunams of planted areas. It is important to control the velocity and water level along the river to maintain the required level for easily diverting water to the branches located along the river. So, in this research, a numerical model was developed to simulate the gradually varied unsteady flow in Shatt AL-Hilla. The present study aims to solve the continuity and momentum (Saint-Venant) equations numerically to predict the hydraulic characteristics in the river using Galerkin finite element method. A computer program was designed and built using the programming language FORTRAN-77. Fifty kilometers was considered starting from downstream of Hindiyah Barrage towards Hilla City. The gathered field measurements along different periods were used for the purpose of calibration and verification of the model. The results show that the suitable Manning roughness was 0.023. A comparison with field observations was conducted to identify the validity of the numerical solution of the flow equations. The obtained results indicate the feasibility of the numerical techniques using a weighting factor of 0.667 and a time increment of 6 hr. High accuracy and good agreement were achieved, and minimum Root Mean Square Error (RMSE) of 0.029 was gained for the obtained results compared with the corresponding field observations.

This paper studies to estimate the dynamic behavior of a demineralized water tank with a piled raft foundation system considering soil-pile-structure-fluid interaction to shock-ground motion. A three-dimensional finite element model of a coupled system is constituted in ANSYS software. Interaction between pile and soil is represented with the frictional contact element. The frictionless contact elements are utilized to model between the water and tank shell to allow for displacement of the free surface adjacent to the tank wall. Shell elements are used for the tank body and its vault. The dynamic analyses of the tank including soil-pile-structure-fluid interaction are presented by using shock response spectra. Ground shock acceleration time histories, generated by using a developed computer program based on Fortran programming language, produce shock response spectra. The effects of the different charge weights and distances from the charge center are examined in the analyses. Also, the effect of the water fill level in the tank and the number of piles is also investigated. The results of the research are presented with the directional displacements and equivalent stresses. It seen from the analyses that the dynamic responses of the tank increase with the charge weight, while decreasing with the charge center distance. Moreover, the water fill level and the number of piles extremely affect the displacement and stress values of the coupled interaction system.

Abstract. Climate modelling requires spending an extensive amount of time programming, which means reading, learning, testing, and evaluating source code. Fortunately, many climate models have been developed within the past decades, making it easier for climate studies to be conducted on a global scale. However, some climate models have millions of code lines, making the introduction of new parameterizations a laborious task that demands teamwork. While it is true that the high-complexity models perform realistic climate simulations, some researchers perform their studies using simplified climate models in the preliminary test phases. This realization motivated the development of Daily INSOLation (DINSOL-v1.0), a robust computer program to support the simplified climate models, performing solar radiation calculations while considering Milankovitch cycles and offering various simulation options for its users. DINSOL was intended to function as a program that supplies data (e.g. daily insolation, instantaneous solar radiation, orbital parameters of the Earth, and calendar dates), such as the Paleoclimate Modelling Intercomparison Project (PMIP). While preparing the boundary conditions of solar radiation for climate models, it was realized that the DINSOL model could also be a helpful tool for use in classrooms. Thus, it was decided that an intuitive graphical user interface would be required to cater to this educational purpose. The model was written in the Fortran 90 language, while its graphical user interface would be built using PyGTK, a Python application programming interface (API) based on GIMP ToolKit (GTK). Furthermore, the R language would also be used to generate a panel containing contour fields and sketches of the orbital parameters to support the graphical execution. The model evaluation made use of data from PMIP and other tools, and the data analysis was performed through statistical methods. Once all tests were concluded, an insignificant difference between the DINSOL-obtained results and the results obtained from other models validated the viability of DINSOL as a dependable tool.

A study has been done to represent the pressure changes along gathering system in pipelines transporting Iraqi's crude oils; the study is divided into four parts. The first part represents the calculations of pressure drop in pipelines transporting petroleum fluid from the well head to a gathering point. In this part, there is a two-phase flow (gas and liquid). The calculations of pressure change in this part depends upon determination of some properties such as liquid and gas density, liquid and gas viscosity, liquid hold up and friction factor. Determining the liquid hold up and then pressure drop are achieved using two methods, the first method is modified Beggs and Brill correlation, depending on three assumed flow patterns. The second is Aziz et al. correlation, depending on three flow patterns also but are different to that of modified Beggs and Brill. While a method of Colebrook used in determination of two-phase friction factor. The results of two-phase flow calculations show that modified Beggs and Brill correlation (having error of 0.26%) better than Aziz et al. correlation (having error of 0.55%). In the second part there are calculations of pressure change in liquid flow in a pipeline from the gathering point to the first stage of separators. In this part Colebrook correlation is used to determine the friction factor, Brill and Mukherjee method is used for calculation of pressure change. Mukherjee and Brill method gave good results with respect to the pressure drop of flow in the axial pipeline after the gathering point of the actual field data. The third part deals with the networking in pipelines, types of gathering systems presented and discussed, the calculations of pressure change in a simple gathering system is studied. The fourth part discusses optimization techniques; Constrained Rosenbrock is used to find optimum pressure which gives favorable oil properties. They have been achieved with some assumptions; they are: Minimum Produced gas oil ratio. Minimum formation volume factor. Maximum API gravity. Finally, two computer programs are developed. Each program performs all the calculations of the four parts. The first program is developed using FORTRAN language, while the second is developed using Visual Basic language.

AbstractA complex binary trait is a character that has a dichotomous expression but with a polygenic genetic background. Mapping quantitative trait loci (QTL) for such traits is difficult because of the discrete nature and the reduced variation in the phenotypic distribution. Bayesian statistics are proved to be a powerful tool for solving complicated genetic problems, such as multiple QTL with nonadditive effects, and have been successfully applied to QTL mapping for continuous traits. In this study, we show that Bayesian statistics are particularly useful for mapping QTL for complex binary traits. We model the binary trait under the classical threshold model of quantitative genetics. The Bayesian mapping statistics are developed on the basis of the idea of data augmentation. This treatment allows an easy way to generate the value of a hypothetical underlying variable (called the liability) and a threshold, which in turn allow the use of existing Bayesian statistics. The reversible jump Markov chain Monte Carlo algorithm is used to simulate the posterior samples of all unknowns, including the number of QTL, the locations and effects of identified QTL, genotypes of each individual at both the QTL and markers, and eventually the liability of each individual. The Bayesian mapping ends with an estimation of the joint posterior distribution of the number of QTL and the locations and effects of the identified QTL. Utilities of the method are demonstrated using a simulated outbred full-sib family. A computer program written in FORTRAN language is freely available on request.

The presented numerical methodology is based on the finite element method (FEM) and computational procedures of the NASTRAN software package. It allows to investigate the influence of geometric imperfections in the shape of thin-walled rods of open profile on the critical values of the load, the shape of the stability loss and the stress-strain state. It has been developed an algorithm for computer modeling of initial imperfections in the shape of thin-walled rods, which is implemented in the NASTRAN software package using a neutral NASTRAN PC file and a specially developed program written in FORTRAN language and adapted to this software package. Geometric imperfections of the rods can be represented as their form of loss of stability or the form of deformation from the action of the load with the possibility of varying the maximum value of the imperfections amplitude. Computational procedures for solving the Lanczos stability problem and the geometrically nonlinear static problem by the Newton-Rafson method can be used to model imperfections. The program developed by the authors allows to form new nodal coordinates of a finite-element model of rods and to visualize geometric imperfections in a given scale. The article provides a step-by-step description of finite-element construction models of thin-walled rod of open profile with an ideal surface and taking into account the imperfection of the form, which is presented as the first form of loss of rod stability from longitudinal load applied with eccentricity. With the help of the FEMAP NASTRAN preprocessor is forming the geometry of the middle surface of an ideal rod, and setting the mechanical characteristics of the material, boundary conditions and load. The middle surface of the rod is fed as a set of flat quadrangular finite elements with six degrees of freedom in the node. In the article, a linear calculation of the stability by the Lanzosch method is performed to obtain the form of rod geometric imperfection. Setting the maximum amplitude of imperfections was performed using the program developed by the authors. Using the Newton-Rafson method, the geometrically nonlinear problem of rod statics with a given shape imperfection is solved, the critical value of the longitudinal load is determined, and the corresponding form of the rod stability loss is obtained. The presented numerical technique and the developed algorithm of computer modeling of shape imperfections allow to investigate in nonlinear formulation the stability of open profile thin-walled rods taking into account geometric imperfections of different amplitude as different forms of rod deformation, including the form of stability loss, to assess the impact of imperfections on the critical value of the load, the form of stability loss and stress-strain state. The presented algorithm and numerical technique can be used to study the stability of such thin-walled structural elements as shells, plates and others.

Numerical methods today play a useful and important role in solving various problems related to fracture mechanics including modeling crack propagation, fretting fatigue and cohesion... Furthermore, these methods have been widely used to solve problems in linear and nonlinear fracture mechanics in cases of elastic, plastic fracture problems. The evaluation of stress intensity factor in 2D and 3D geometries, thus these techniques widely used for non-standard crack configurations. The objective of this work is study the effects of the crack length and the number of structural elements on the two crack parameters such as the stress intensity factor KI and KII and the contour integral (J). As well as presenting a numerical modeling of crack propagation, for a LEHIM (Linear Elastic Homogeneous Isotopic Material) with mechanical characteristics by the method SFEMD (Stretching Finite Element Method Developed), the model chosen with quadratic elements with 4 nodes (CPE4). However, this method is based on the effect of the number of contours and the number of elements around the crack tip on the variation of the stress intensity factors. In addition, the crack propagation criterion (MCSC) was used, a computer program was created in FORTRAN language to develop and evaluate the stress intensity factors and the contour integral (J). Several examples of crack lengths a = 0.7, 1.4, 2.1, 2.8 and 3.5 mm were used. Additionally, the number of items has been changed several times. The stress intensity factors of modes I and II and direction angles (α) are calculated to solve the problem using the ABAQUS finite element code. The results obtained by the SFEMD method and the results of the analytical method are very close.

Vibration in cars is undesirable because it causes discomfort to passengers, and can also lead to fatigue and failure of some parts of the vehicle. Therefore, the study and analysis of comments movements cart embedded in ever to research vehicles since the invention. And associated vibration cart passenger comfort, safety and stability of the vehicle. The researchers analyzed several vibration of vehicles by looking at different models, such as quarter wagon model ,and Half Car Model and full vehicle model with different types of excitement experienced by the vehicle and intended here excitement is a set of external forces arising from the terrain. This research includes a half vehicle linear model , written for four degrees of freedom plus one (4 +1 DOF) after addition degree of freedom which is driver / passenger seat system becomes a five degrees of freedom, also the vehicle body is assumed as a rigid body and taking into account the Bounce and Pitch. The system governing equations of motion are formulated by using the finite element method (FEM). A Fortran language computer program has been established for this purpose and used in the process covering (Simulation) and stand on the performance evaluation and analysis riding cart at the design stage and stand on the impact driver way through a study on the subject and the quality of the driver's seat, Two criterion of standards of comfort has been used, such as standard rate of absorbed energy (Average Absorbed Power) to be the norm over the driver comfort or not. And the comfort factor which is the vertical acceleration root mean square is used as an indication for the ride comfort. In factthe driver is the most important link in the process of using vehicles because the decision-maker and dominant direct the movement of vehicle.

AbstractStructured programming is no longer enough for dealing with the large software projects allowed by today's computer hardware. An object-oriented computational model has been developed in order to achieve reuse, rapid prototyping and easy maintenance in large scale materials science calculations. The exclusive use of an object-oriented language is not mandatory for implementing the model. On the contrary, embedding Fortran code in an object-oriented language can be a very efficient way of fulfilling these goals without sacrificing the huge installed base of Fortran programs. Reuse can begin from one's old Fortran programs. These claims are substantiated with practical examples from a professional code for the study of the electronic properties of atomic clusters. Out of the about 20,000 lines of the original Fortran program, more than 70% of them could be reused in the C++ objects of the new version. Facilities for dealing with periodic systems and for scaling linearly with the number of atoms have been added without any change in the computational model.

The case of an unstable period at the initial stage of extrusion of a stepped sintered sample with a circular cross-section was simulated in the ABAQUS software environment. From the top of the cylindrical sample, uniform movement in the vertical direction is given, because of which it was deformed. Zones of von Mises stress, strain intensity, components of the deformation state and porosity of the material are obtained. The data were found for seven nodes at the entrance (е-е) and exit (д-д) from the matrix, as well as for six elements above and below them, which are presented in the form of a table. All values of deformations reach a maximum in the zones of contact between the matrix and the bar. The data obtained made it possible to plot the graphs of the components of the deformation state of the upper elements of the sections е-е and д-д and changes in porosity at the nodes of these sections. The largest of these in the е-е zone are axial deformations compression and shift deformations. In the zone д-д, shift deformations are very small compared to е-е and have changed their sign. The rest of the data qualitatively coincide with the calculated data of the program compiled in the algorithmic language FORTRAN-IV on the ЭС 1022 computer.

Purpose. The article presents a new method for numerical simulation of quasi-eigenmode oscillations in open resonators of gyrotrons — powerful vacuum generators of electromagnetic waves in the millimeter and submillimeter ranges. The gyrotron cavity has the shape of a weakly inhomogeneous hollow circular metal waveguide. Methods. The proposed approach uses the inhomogeneous string equation with radiation boundary conditions to formulate a nonlinear spectral boundary value problem describing oscillations in a resonator, neglecting the couplings of waves with different radial indices. By linearizing with respect to frequency the radiation boundary conditions, the boundary value problem is reduced to a linear boundary value problem. To discretize this boundary value problem, the finite difference method is used and a linear generalized matrix eigenvalue problem is formulated. This problem is solved by the Arnoldi method with eigenvalues calculation in a shift-invert mode. An iterative algorithm is proposed that makes it possible to sequentially calculate a given number of frequencies and quality factors of quasi-eigenmodes of oscillations. Results. The computer program was developed written in the Wolfram Language and Fortran using the algorithms proposed in the work. The results of test calculations for real gyrotron resonators are presented, which demonstrate the high accuracy of the obtained values of frequencies, quality factors and field distributions of quasi-eigenmode oscillations in the studied resonators. Conclusion. The methods, algorithms and created program proposed in the article can significantly facilitate the process of developing gyrotrons intended for various practical applications and operating in new frequency ranges. The method of iterative refinement of boundary conditions can be generalized to the case of equations of the linear theory of a gyrotron and used to develop new methods for analyzing the starting conditions for the soft self-excitation in gyrotrons — generators.

Internet Relay Chat (IRC) is a text-based computer-mediated communication (CMC) service in which people can meet and chat in real time. Most chat occurs in channels named for a specific topic, such as #usa or #linux. A user can take part in several channels when connected to an IRC network. For a long time the only major IRC network available was EFnet, founded in 1990. Over the 1990s three other major IRC networks developed, Undernet (1993), DALnet (1994) and IRCnet (which split from EFnet in June 1996). Several causes led to the separate development of IRC networks: fast growth of user numbers, poor scalability of the IRC protocol and content disagreements, like allowing or prohibiting 'bot programs. Today we are experiencing the development of regional IRC networks, such as BrasNet for Brazilian users, and increasing regionalisation of the global networks -- IRCnet users are generally European, EFnet users generally from the Americas and Australia. All persons connecting to an IRC network at one time create that IRC network's user space. People are constantly signing on and off each network. The total number of users who have ever been to a specific IRC network could be called its 'social space' and an IRC network's social space is by far larger than its user space at any one time. Although there has been research on IRC almost from its beginning (it was developed in 1988, and the first research was made available in late 1991 (Reid)), resources on quantitative development are rare. To rectify this situation, a quantitative data logging 'bot program -- Socip -- was created and set to run on various IRC networks. Socip has been running for almost two years on several IRC networks, giving Internet researchers empirical data of the quantitative development of IRC. Methodology Any approach to gathering quantitative data on IRC needs to fulfil the following tasks: Store the number of users that are on an IRC network at a given time, e.g. every five minutes; Store the number of channels; and, Store the number of servers. It is possible to get this information using the '/lusers' command on an IRC-II client, entered by hand. This approach yields results as in Table 1. Table 1: Number of IRC users on January 31st, 1995 Date Time Users Invisible Servers Channels 31.01.95 10:57 2737 2026 93 1637 During the first months of 1995, it was even possible to get all user information using the '/who **' command. However, on current major IRC networks with greater than 50000 users this method is denied by the IRC Server program, which terminates the connection because it is too slow to accept that amount of data. Added to this problem is the fact that collecting these data manually is an exhausting and repetitive task, better suited to automation. Three approaches to automation were attempted in the development process. The 'Eggdrop' approach The 'Eggdrop' 'bot is one of the best-known IRC 'bot programs. Once programmed, 'bots can act autonomously on an IRC network, and Eggdrop was considered particularly convenient because customised modules could be easily installed. However, testing showed that the Eggdrop 'bot was unsuitable for two reasons. The first was technical: for reasons undetermined, all Eggdrop modules created extensive CPU usage, making it impossible to run several Eggdrops simultaneously to research a number of IRC networks. The second reason had to do with the statistics to be obtained. The objective was to get a snapshot of current IRC users and IRC channel use every five minutes, written into an ASCII file. It was impossible to extend Eggdrop's possibilities in a way that it would periodically submit the '/lusers' command and write the received data into a file. For these reasons, and some security concerns, the Eggdrop approach was abandoned. IrcII was a UNIX IRC client with its own scripting language, making it possible to write command files which periodically submit the '/lusers' command to any chosen IRC server and log the command's output. Four different scripts were used to monitor IRCnet, EFnet, DALnet and Undernet from January to October 1998. These scripts were named Socius_D, Socius_E, Socius_I and Socius_U (depending on the network). Every hour each script stored the number of users and channels in a logfile (examinable using another script written in the Perl language). There were some drawbacks to the ircII script approach. While the need for a terminal to run on could be avoided using the 'screen' package -- making it possible to start ircII, run the scripts, detach, and log off again -- it was impossible to restart ircII and the scripts using an automatic task-scheduler. Thus periodic manual checks were required to find out if the scripts were still running and restart them if needed (e.g. if the server connection was lost). These checks showed that at least one script would not be running after 10 hours. Additional disadvantages were the lengthy log files and the necessity of providing a second program to extract the log file data and write it into a second file from which meaningful graphs could be created. The failure of the Eggdrop and ircII scripting approaches lead to the solution still in use today. Perl script-only approach Perl is a powerful script language for handling file-oriented data when speed is not extremely important. Its version 5 flavour allows a lot of modules to use it for expansion, including the Net::IRC package. The object-oriented Perl interface enables Perl scripts to connect to an IRC server, and use the basic IRC commands. The Socip.pl program includes all server definitions needed to create connections. Socip is currently monitoring ten major IRC networks, including DALnet, EFnet, IRCnet, the Microsoft Network, Talkcity, Undernet and Galaxynet. When run, "Social science IRC program" selects a nickname from its list corresponding to the network -- For EFnet, the first nickname used is Socip_E1. It then functions somewhat like a 'bot. Using that nickname, Socip tries to create an IRC connection to a server of the given network. If there is no failure, handlers are set up which take care of proper reactions to IRC server messages (such as Ping-pong, message output and reply). Socip then joins the channel #hose (the name has no special meaning), a maintenance channel with the additional effect of real persons meeting the 'bot and trying to interact with it every now and then. Those interactions are logged too. Sitting in that channel, the script sleeps periodically and checks if a certain time span has passed (the default is five minutes). After that, the '/lusers' command's output is stored in a data file for each IRC network and the IRC network's RRD (Round Robin database) file is updated. This database, which is organised chronologically, offers great detail for recent events and more condensed information for older events. User and channel information younger than 10 days is stored in five-minute detail. If older than two years, the same information is automatically averaged and stored in a per-day resolution. In case of network problems, Socip acts as necessary. For example, it recognises a connection termination and tries to reconnect after pausing by using the next nickname on the list. This prevents nickname collision problems. If the IRC server does not respond to '/luser' commands three times in a row, the next server on the list is accessed. Special (crontab-invoked) scripts take care of restarting Socip when necessary, as in termination of script because of network problems, IRC operator kill or power failure. After a reboot all scripts are automatically restarted. All monitoring is done on a Linux machine (Pentium 120, 32 MB, Debian Linux 2.1) which is up all the time. Processor load is not extensive, and this machine also acts as the Sociology Department's WWW-Server. Graphs creation Graphs can be created from the data in Socip's RRD files. This task is done using the MRTG (multi router traffic grapher) program by Tobias Oetiker. A script updates all IRC graphs four times a day. Usage of each IRC network is visualised through five graphs: Daily, Weekly and Monthly users and channels, accompanied by two graphs showing all known data users/channels and servers. All this information is continuously published on the World Wide Web at http://www.hinner.com/ircstat. Figures The following samples demonstrate what information can be produced by Socip. As already mentioned, graphs of all monitored networks are updated four times a day, with five graphs for each IRC network. Figure 1 shows the rise of EFnet users from about 40000 in November 1998 to 65000 in July 2000. Sampled data is oscillating around an average amount, which is resulting from the different time zones of users. Fig. 1: EFnet - Users and Channels since November 1998 Figure 2 illustrates the decrease of interconnected EFnet servers over the years. Each server is now handling more and more users. Reasons for taking IRC servers off the net are security concerns (attacks on the server by malicious persons), new payment schemes, maintenance and cost effort. Fig. 2: EFnet - Servers since November 1998 A nice example of a heavily changing weekly graph is Figure 3, which shows peaks shortly before 6pm CEST and almost no users shortly after midnight. Fig. 3: Galaxynet: Weekly Graph (July, 15th-22nd, 2000) The daily graph portrays usage variations with even more detail. Figure 4 is taken from Undernet user and channel data. The vertical gap in the graph indicates missing data, caused either by a net split or other network problems. Fig. 4: Undernet: Daily Graph: July, 22nd, 2000 The final example (Figure 5) shows a weekly graph of the Webchat (http://www.webchat.org) network. It can be seen that every day the user count varies from 5000 to nearly 20000, and that channel numbers fluctuate in concert accordingly from 2500 to 5000. Fig. 5: Webchat: Monthly graph, Week 24-29, 2000 Not every IRC user is connected all the time to an IRC network. This figure may have increased lately with more and more flatrates and cheap Internet access offers, but in general most users will sign off the network after some time. This is why IRC is a very dynamic society, with its membership constantly in flux. Maximum user counts only give the highest number of members who were simultaneously online at some point, and one could only guess at the number of total users of the network -- that is, including those who are using that IRC service but are not signed on at that time. To answer these questions, more thorough investigation is necessary. Then inflows and outflows might be more readily estimated. Table 2 shows the all time maximum user counts of seven IRC networks, compared to the average numbers of IRC users of the four major IRC networks during the third quarter 1998 (based on available data). Table 2: Maximum user counts of selected IRC networks DALnet EFnet Galaxy Net IRCnet MS Chat Undernet Webchat Max. 2000 64276 64309 15253 65340 17392 60210 19793 3rd Q. 1998 21000 37000 n/a 24500 n/a 24000 n/a Compared with the 200-300 users in 1991 and the 7000 IRC-chatters in 1994, the recent growth is certainly extraordinary: it adds up to a total of 306573 users across all monitored networks. It can be expected that the 500000 IRC user threshold will be passed some time during the year 2001. As a final remark, it should be said that obviously Web-based chat systems will be more and more common in the future. These chat services do not use standard IRC protocols, and will be very hard to monitor. Given that these systems are already quite popular, the actual number of chat users in the world could have already passed the half million landmark. References Reid, Elizabeth. "Electropolis: Communications and Community on Internet Relay Chat." Unpublished Honours Dissertation. U of Melbourne, 1991. The Socip program can be obtained at no cost from http://www.hinner.com. Most IRC networks can be accessed with the original Net::Irc Perl extension, but for some special cases (e.g. Talkcity) an extended version is needed, which can also be found there. Citation reference for this article MLA style: Kajetan Hinner. "Statistics of Major IRC Networks: Methods and Summary of User Count." M/C: A Journal of Media and Culture 3.4 (2000). [your date of access] <http://www.api-network.com/mc/0008/count.php>. Chicago style: Kajetan Hinner, "Statistics of Major IRC Networks: Methods and Summary of User Count," M/C: A Journal of Media and Culture 3, no. 4 (2000), <http://www.api-network.com/mc/0008/count.php> ([your date of access]). APA style: Kajetan Hinner. (2000) Statistics of major IRC networks: methods and summary of user count. M/C: A Journal of Media and Culture 3(4). <http://www.api-network.com/mc/0008/count.php> ([your date of access]).

“As the old technologies become automatic and invisible, we find ourselves more concerned with fighting or embracing what’s new”—Dennis Baron, From Pencils to Pixels: The Stage of Literacy Technologies What constitutes a computer, as we have come to expect it? Are they necessarily monolithic “beige boxes”, connected to computer monitors, sitting on computer desks, located in computer rooms or computer labs? In order for a device to be considered a true computer, does it need to have a keyboard and mouse? If this were 1991 or earlier, our collective perception of what computers are and are not would largely be framed by this “beige box” model: computers are stationary, slab-like, and heavy, and their natural habitats must be in rooms specifically designated for that purpose. In 1992, when Apple introduced the first PowerBook, our perception began to change. Certainly there had been other portable computers prior to that, such as the Osborne 1, but these were more luggable than portable, weighing just slightly less than a typical sewing machine. The PowerBook and subsequent waves of laptops, personal digital assistants (PDAs), and so-called smart phones from numerous other companies have steadily forced us to rethink and redefine what a computer is and is not, how we interact with them, and the manner in which these tools might be used in the classroom. However, this reconceptualization of computers is far from over, and is in fact steadily evolving as new devices are introduced, adopted, and subsequently adapted for uses beyond of their original purpose. Pat Crowe’s Book Reader project, for example, has morphed Nintendo’s GameBoy and GameBoy Advance into a viable electronic book platform, complete with images, sound, and multi-language support. (Crowe, 2003) His goal was to take this existing technology previously framed only within the context of proprietary adolescent entertainment, and repurpose it for open, flexible uses typically associated with learning and literacy. Similar efforts are underway to repurpose Microsoft’s Xbox, perhaps the ultimate symbol of “closed” technology given Microsoft’s propensity for proprietary code, in order to make it a viable platform for Open Source Software (OSS). However, these efforts are not forgone conclusions, and are in fact typical of the ongoing battle over who controls the technology we own in our homes, and how open source solutions are often at odds with a largely proprietary world. In late 2001, Microsoft launched the Xbox with a multimillion dollar publicity drive featuring events, commercials, live models, and statements claiming this new console gaming platform would “change video games the way MTV changed music”. (Chan, 2001) The Xbox launched with the following technical specifications: 733mhz Pentium III 64mb RAM, 8 or 10gb internal hard disk drive CD/DVD ROM drive (speed unknown) Nvidia graphics processor, with HDTV support 4 USB 1.1 ports (adapter required), AC3 audio 10/100 ethernet port, Optional 56k modem (TechTV, 2001) While current computers dwarf these specifications in virtually all areas now, for 2001 these were roughly on par with many desktop systems. The retail price at the time was $299, but steadily dropped to nearly half that with additional price cuts anticipated. Based on these features, the preponderance of “off the shelf” parts and components used, and the relatively reasonable price, numerous programmers quickly became interested in seeing it if was possible to run Linux and additional OSS on the Xbox. In each case, the goal has been similar: exceed the original purpose of the Xbox, to determine if and how well it might be used for basic computing tasks. If these attempts prove to be successful, the Xbox could allow institutions to dramatically increase the student-to-computer ratio in select environments, or allow individuals who could not otherwise afford a computer to instead buy and Xbox, download and install Linux, and use this new device to write, create, and innovate . This drive to literally and metaphorically “open” the Xbox comes from many directions. Such efforts include Andrew Huang’s self-published “Hacking the Xbox” book in which, under the auspices of reverse engineering, Huang analyzes the architecture of the Xbox, detailing step-by-step instructions for flashing the ROM, upgrading the hard drive and/or RAM, and generally prepping the device for use as an information appliance. Additional initiatives include Lindows CEO Michael Robertson’s $200,000 prize to encourage Linux development on the Xbox, and the Xbox Linux Project at SourceForge. What is Linux? Linux is an alternative operating system initially developed in 1991 by Linus Benedict Torvalds. Linux was based off a derivative of the MINIX operating system, which in turn was a derivative of UNIX. (Hasan 2003) Linux is currently available for Intel-based systems that would normally run versions of Windows, PowerPC-based systems that would normally run Apple’s Mac OS, and a host of other handheld, cell phone, or so-called “embedded” systems. Linux distributions are based almost exclusively on open source software, graphic user interfaces, and middleware components. While there are commercial Linux distributions available, these mainly just package the freely available operating system with bundled technical support, manuals, some exclusive or proprietary commercial applications, and related services. Anyone can still download and install numerous Linux distributions at no cost, provided they do not need technical support beyond the community / enthusiast level. Typical Linux distributions come with open source web browsers, word processors and related productivity applications (such as those found in OpenOffice.org), and related tools for accessing email, organizing schedules and contacts, etc. Certain Linux distributions are more or less designed for network administrators, system engineers, and similar “power users” somewhat distanced from that of our students. However, several distributions including Lycoris, Mandrake, LindowsOS, and other are specifically tailored as regular, desktop operating systems, with regular, everyday computer users in mind. As Linux has no draconian “product activation key” method of authentication, or digital rights management-laden features associated with installation and implementation on typical desktop and laptop systems, Linux is becoming an ideal choice both individually and institutionally. It still faces an uphill battle in terms of achieving widespread acceptance as a desktop operating system. As Finnie points out in Desktop Linux Edges Into The Mainstream: “to attract users, you need ease of installation, ease of device configuration, and intuitive, full-featured desktop user controls. It’s all coming, but slowly. With each new version, desktop Linux comes closer to entering the mainstream. It’s anyone’s guess as to when critical mass will be reached, but you can feel the inevitability: There’s pent-up demand for something different.” (Finnie 2003) Linux is already spreading rapidly in numerous capacities, in numerous countries. Linux has “taken hold wherever computer users desire freedom, and wherever there is demand for inexpensive software.” Reports from technology research company IDG indicate that roughly a third of computers in Central and South America run Linux. Several countries, including Mexico, Brazil, and Argentina, have all but mandated that state-owned institutions adopt open source software whenever possible to “give their people the tools and education to compete with the rest of the world.” (Hills 2001) The Goal Less than a year after Microsoft introduced the The Xbox, the Xbox Linux project formed. The Xbox Linux Project has a goal of developing and distributing Linux for the Xbox gaming console, “so that it can be used for many tasks that Microsoft don’t want you to be able to do. ...as a desktop computer, for email and browsing the web from your TV, as a (web) server” (Xbox Linux Project 2002). Since the Linux operating system is open source, meaning it can freely be tinkered with and distributed, those who opt to download and install Linux on their Xbox can do so with relatively little overhead in terms of cost or time. Additionally, Linux itself looks very “windows-like”, making for fairly low learning curve. To help increase overall awareness of this project and assist in diffusing it, the Xbox Linux Project offers step-by-step installation instructions, with the end result being a system capable of using common peripherals such as a keyboard and mouse, scanner, printer, a “webcam and a DVD burner, connected to a VGA monitor; 100% compatible with a standard Linux PC, all PC (USB) hardware and PC software that works with Linux.” (Xbox Linux Project 2002) Such a system could have tremendous potential for technology literacy. Pairing an Xbox with Linux and OpenOffice.org, for example, would provide our students essentially the same capability any of them would expect from a regular desktop computer. They could send and receive email, communicate using instant messaging IRC, or newsgroup clients, and browse Internet sites just as they normally would. In fact, the overall browsing experience for Linux users is substantially better than that for most Windows users. Internet Explorer, the default browser on all systems running Windows-base operating systems, lacks basic features standard in virtually all competing browsers. Native blocking of “pop-up” advertisements is still not yet possible in Internet Explorer without the aid of a third-party utility. Tabbed browsing, which involves the ability to easily open and sort through multiple Web pages in the same window, often with a single mouse click, is also missing from Internet Explorer. The same can be said for a robust download manager, “find as you type”, and a variety of additional features. Mozilla, Netscape, Firefox, Konqueror, and essentially all other OSS browsers for Linux have these features. Of course, most of these browsers are also available for Windows, but Internet Explorer is still considered the standard browser for the platform. If the Xbox Linux Project becomes widely diffused, our students could edit and save Microsoft Word files in OpenOffice.org’s Writer program, and do the same with PowerPoint and Excel files in similar OpenOffice.org components. They could access instructor comments originally created in Microsoft Word documents, and in turn could add their own comments and send the documents back to their instructors. They could even perform many functions not yet capable in Microsoft Office, including saving files in PDF or Flash format without needing Adobe’s Acrobat product or Macromedia’s Flash Studio MX. Additionally, by way of this project, the Xbox can also serve as “a Linux server for HTTP/FTP/SMB/NFS, serving data such as MP3/MPEG4/DivX, or a router, or both; without a monitor or keyboard or mouse connected.” (Xbox Linux Project 2003) In a very real sense, our students could use these inexpensive systems previously framed only within the context of entertainment, for educational purposes typically associated with computer-mediated learning. Problems: Control and Access The existing rhetoric of technological control surrounding current and emerging technologies appears to be stifling many of these efforts before they can even be brought to the public. This rhetoric of control is largely typified by overly-restrictive digital rights management (DRM) schemes antithetical to education, and the Digital Millennium Copyright Act (DMCA). Combined,both are currently being used as technical and legal clubs against these efforts. Microsoft, for example, has taken a dim view of any efforts to adapt the Xbox to Linux. Microsoft CEO Steve Ballmer, who has repeatedly referred to Linux as a cancer and has equated OSS as being un-American, stated, “Given the way the economic model works - and that is a subsidy followed, essentially, by fees for every piece of software sold - our license framework has to do that.” (Becker 2003) Since the Xbox is based on a subsidy model, meaning that Microsoft actually sells the hardware at a loss and instead generates revenue off software sales, Ballmer launched a series of concerted legal attacks against the Xbox Linux Project and similar efforts. In 2002, Nintendo, Sony, and Microsoft simultaneously sued Lik Sang, Inc., a Hong Kong-based company that produces programmable cartridges and “mod chips” for the PlayStation II, Xbox, and Game Cube. Nintendo states that its company alone loses over $650 million each year due to piracy of their console gaming titles, which typically originate in China, Paraguay, and Mexico. (GameIndustry.biz) Currently, many attempts to “mod” the Xbox required the use of such chips. As Lik Sang is one of the only suppliers, initial efforts to adapt the Xbox to Linux slowed considerably. Despite that fact that such chips can still be ordered and shipped here by less conventional means, it does not change that fact that the chips themselves would be illegal in the U.S. due to the anticircumvention clause in the DMCA itself, which is designed specifically to protect any DRM-wrapped content, regardless of context. The Xbox Linux Project then attempted to get Microsoft to officially sanction their efforts. They were not only rebuffed, but Microsoft then opted to hire programmers specifically to create technological countermeasures for the Xbox, to defeat additional attempts at installing OSS on it. Undeterred, the Xbox Linux Project eventually arrived at a method of installing and booting Linux without the use of mod chips, and have taken a more defiant tone now with Microsoft regarding their circumvention efforts. (Lettice 2002) They state that “Microsoft does not want you to use the Xbox as a Linux computer, therefore it has some anti-Linux-protection built in, but it can be circumvented easily, so that an Xbox can be used as what it is: an IBM PC.” (Xbox Linux Project 2003) Problems: Learning Curves and Usability In spite of the difficulties imposed by the combined technological and legal attacks on this project, it has succeeded at infiltrating this closed system with OSS. It has done so beyond the mere prototype level, too, as evidenced by the Xbox Linux Project now having both complete, step-by-step instructions available for users to modify their own Xbox systems, and an alternate plan catering to those who have the interest in modifying their systems, but not the time or technical inclinations. Specifically, this option involves users mailing their Xbox systems to community volunteers within the Xbox Linux Project, and basically having these volunteers perform the necessary software preparation or actually do the full Linux installation for them, free of charge (presumably not including shipping). This particular aspect of the project, dubbed “Users Help Users”, appears to be fairly new. Yet, it already lists over sixty volunteers capable and willing to perform this service, since “Many users don’t have the possibility, expertise or hardware” to perform these modifications. Amazingly enough, in some cases these volunteers are barely out of junior high school. One such volunteer stipulates that those seeking his assistance keep in mind that he is “just 14” and that when performing these modifications he “...will not always be finished by the next day”. (Steil 2003) In addition to this interesting if somewhat unusual level of community-driven support, there are currently several Linux-based options available for the Xbox. The two that are perhaps the most developed are GentooX, which is based of the popular Gentoo Linux distribution, and Ed’s Debian, based off the Debian GNU / Linux distribution. Both Gentoo and Debian are “seasoned” distributions that have been available for some time now, though Daniel Robbins, Chief Architect of Gentoo, refers to the product as actually being a “metadistribution” of Linux, due to its high degree of adaptability and configurability. (Gentoo 2004) Specifically, the Robbins asserts that Gentoo is capable of being “customized for just about any application or need. ...an ideal secure server, development workstation, professional desktop, gaming system, embedded solution or something else—whatever you need it to be.” (Robbins 2004) He further states that the whole point of Gentoo is to provide a better, more usable Linux experience than that found in many other distributions. Robbins states that: “The goal of Gentoo is to design tools and systems that allow a user to do their work pleasantly and efficiently as possible, as they see fit. Our tools should be a joy to use, and should help the user to appreciate the richness of the Linux and free software community, and the flexibility of free software. ...Put another way, the Gentoo philosophy is to create better tools. When a tool is doing its job perfectly, you might not even be very aware of its presence, because it does not interfere and make its presence known, nor does it force you to interact with it when you don’t want it to. The tool serves the user rather than the user serving the tool.” (Robbins 2004) There is also a so-called “live CD” Linux distribution suitable for the Xbox, called dyne:bolic, and an in-progress release of Slackware Linux, as well. According to the Xbox Linux Project, the only difference between the standard releases of these distributions and their Xbox counterparts is that “...the install process – and naturally the bootloader, the kernel and the kernel modules – are all customized for the Xbox.” (Xbox Linux Project, 2003) Of course, even if Gentoo is as user-friendly as Robbins purports, even if the Linux kernel itself has become significantly more robust and efficient, and even if Microsoft again drops the retail price of the Xbox, is this really a feasible solution in the classroom? Does the Xbox Linux Project have an army of 14 year olds willing to modify dozens, perhaps hundreds of these systems for use in secondary schools and higher education? Of course not. If such an institutional rollout were to be undertaken, it would require significant support from not only faculty, but Department Chairs, Deans, IT staff, and quite possible Chief Information Officers. Disk images would need to be customized for each institution to reflect their respective needs, ranging from setting specific home pages on web browsers, to bookmarks, to custom back-up and / or disk re-imaging scripts, to network authentication. This would be no small task. Yet, the steps mentioned above are essentially no different than what would be required of any IT staff when creating a new disk image for a computer lab, be it one for a Windows-based system or a Mac OS X-based one. The primary difference would be Linux itself—nothing more, nothing less. The institutional difficulties in undertaking such an effort would likely be encountered prior to even purchasing a single Xbox, in that they would involve the same difficulties associated with any new hardware or software initiative: staffing, budget, and support. If the institutional in question is either unwilling or unable to address these three factors, it would not matter if the Xbox itself was as free as Linux. An Open Future, or a Closed one? It is unclear how far the Xbox Linux Project will be allowed to go in their efforts to invade an essentially a proprietary system with OSS. Unlike Sony, which has made deliberate steps to commercialize similar efforts for their PlayStation 2 console, Microsoft appears resolute in fighting OSS on the Xbox by any means necessary. They will continue to crack down on any companies selling so-called mod chips, and will continue to employ technological protections to keep the Xbox “closed”. Despite clear evidence to the contrary, in all likelihood Microsoft continue to equate any OSS efforts directed at the Xbox with piracy-related motivations. Additionally, Microsoft’s successor to the Xbox would likely include additional anticircumvention technologies incorporated into it that could set the Xbox Linux Project back by months, years, or could stop it cold. Of course, it is difficult to say with any degree of certainty how this “Xbox 2” (perhaps a more appropriate name might be “Nextbox”) will impact this project. Regardless of how this device evolves, there can be little doubt of the value of Linux, OpenOffice.org, and other OSS to teaching and learning with technology. This value exists not only in terms of price, but in increased freedom from policies and technologies of control. New Linux distributions from Gentoo, Mandrake, Lycoris, Lindows, and other companies are just now starting to focus their efforts on Linux as user-friendly, easy to use desktop operating systems, rather than just server or “techno-geek” environments suitable for advanced programmers and computer operators. While metaphorically opening the Xbox may not be for everyone, and may not be a suitable computing solution for all, I believe we as educators must promote and encourage such efforts whenever possible. I suggest this because I believe we need to exercise our professional influence and ultimately shape the future of technology literacy, either individually as faculty and collectively as departments, colleges, or institutions. Moran and Fitzsimmons-Hunter argue this very point in Writing Teachers, Schools, Access, and Change. One of their fundamental provisions they use to define “access” asserts that there must be a willingness for teachers and students to “fight for the technologies that they need to pursue their goals for their own teaching and learning.” (Taylor / Ward 160) Regardless of whether or not this debate is grounded in the “beige boxes” of the past, or the Xboxes of the present, much is at stake. Private corporations should not be in a position to control the manner in which we use legally-purchased technologies, regardless of whether or not these technologies are then repurposed for literacy uses. I believe the exigency associated with this control, and the ongoing evolution of what is and is not a computer, dictates that we assert ourselves more actively into this discussion. We must take steps to provide our students with the best possible computer-mediated learning experience, however seemingly unorthodox the technological means might be, so that they may think critically, communicate effectively, and participate actively in society and in their future careers. About the Author Paul Cesarini is an Assistant Professor in the Department of Visual Communication & Technology Education, Bowling Green State University, Ohio Email: pcesari@bgnet.bgsu.edu Works Cited http://xbox-linux.sourceforge.net/docs/debian.php>.Baron, Denis. “From Pencils to Pixels: The Stages of Literacy Technologies.” Passions Pedagogies and 21st Century Technologies. Hawisher, Gail E., and Cynthia L. Selfe, Eds. Utah: Utah State University Press, 1999. 15 – 33. Becker, David. “Ballmer: Mod Chips Threaten Xbox”. News.com. 21 Oct 2002. http://news.com.com/2100-1040-962797.php>. http://news.com.com/2100-1040-978957.html?tag=nl>. http://archive.infoworld.com/articles/hn/xml/02/08/13/020813hnchina.xml>. http://www.neoseeker.com/news/story/1062/>. http://www.bookreader.co.uk>.Finni, Scott. “Desktop Linux Edges Into The Mainstream”. TechWeb. 8 Apr 2003. http://www.techweb.com/tech/software/20030408_software. http://www.theregister.co.uk/content/archive/29439.html http://gentoox.shallax.com/. http://ragib.hypermart.net/linux/. http://www.itworld.com/Comp/2362/LWD010424latinlinux/pfindex.html. http://www.xbox-linux.sourceforge.net. http://www.theregister.co.uk/content/archive/27487.html. http://www.theregister.co.uk/content/archive/26078.html. http://www.us.playstation.com/peripherals.aspx?id=SCPH-97047. http://www.techtv.com/extendedplay/reviews/story/0,24330,3356862,00.html. http://www.wired.com/news/business/0,1367,61984,00.html. http://www.gentoo.org/main/en/about.xml http://www.gentoo.org/main/en/philosophy.xml http://techupdate.zdnet.com/techupdate/stories/main/0,14179,2869075,00.html. http://xbox-linux.sourceforge.net/docs/usershelpusers.html http://www.cnn.com/2002/TECH/fun.games/12/16/gamers.liksang/. Citation reference for this article MLA Style Cesarini, Paul. "“Opening” the Xbox" M/C: A Journal of Media and Culture <http://www.media-culture.org.au/0406/08_Cesarini.php>. APA Style Cesarini, P. (2004, Jul1). “Opening” the Xbox. M/C: A Journal of Media and Culture, 7, <http://www.media-culture.org.au/0406/08_Cesarini.php>