Symbolic Solution of Linear Differential Equations

An algorithm for solving linear constant-coefficient ordinary differential equations is presented. The computational complexity of the algorithm is discussed and its implementation in the FORMAC system is described. A comparison is made between the algorithm and some classical algorithms for solving differential equations

Applications of symbolic computing methods to the dynamic analysis of large systems

Since the symbolic computing language is very well suited to the operations with algebraic equations, techniques use the transfer function concept as a tool for the analysis of large linear dynamic systems. Techniques were coded in the experimental symbolic computer language FORMAC. The first of these approaches, REDUCE 1, establishes the techniques and a computer program to symbolically reduce arbitrary block diagrams associated with large systems for desired transfer functions. Symbolic closed form solutions are determined in several forms including an expanded form in terms of the driving frequencies and system constants. Programs are also written to numerically evaluate the symbolic solutions. A second computer program, REDUCE 2, is also based on the use of symbolic computing methods and was written to accommodate large engineering systems

A computer program to generate equations of motion matrices, L217 (EOM). Volume 2: Supplemental system design and maintenance document

The equations of motion program L217 (EOM) is described. The program formulates the matrix coefficients for a second order linear differential equation which describes the motion of an airplane relative to its level equilibrium flight condition. Aerodynamic data from FLEXSTAB or Doublet Lattice (L216) programs are used to derive the equations for quasi-steady or complete unsteady aerodynamics

Fiber Optic Tactical Local Network (FOTLAN)

A 100 Mbit/s FDDI (fiber distributed data interface) network interface unit is described that supports real-time data, voice and video. Its high-speed interrupt-driven hardware architecture efficiently manages stream and packet data transfer to the FDDI network. Other enhancements include modular single-mode laser-diode fiber optic links to maximize node spacing, optic bypass switches for increased fault tolerance, and a hardware performance monitor to gather real-time network diagnostics

CRIME AND PUNISHMENT WITH HABIT FORMATION

Moral concepts affect crime supply. This idea is modelled assuming that illegal activities is habit forming. We introduce habits in a intertemporal general equilibrium framework to illegal activities and compare its outcomes with a model without habit formation. The findings are that habit (i) reduces the crime level; (ii) reduces the marginal effect of illegal activities return on crime; (iii) reduces the efficacy of punishment.

Alguns contributos para a qualidade da formação do CENFIM: Caracterização dos formandos, satisfação e sucesso escolar

O CENFIM e um centro de formação profissional, associado à indústria Metalúrgica e Metalomecânica, para empresas, adultos e jovens. Para o sucesso da formação torna-se importante conhecer os fatores que levam os seus formandos a escolher este centro de formação, quais as suas motivações e as razões para o sucesso escolar. Para tal, construiu-se um inquérito por questionário que se distribuiu pelos centros do CENFIM. Neste trabalho analisamos os resultados desse inquérito. Começamos por realizar uma análise exploratória de dados visando caraterizar o tipo de alunos que frequenta o Centro. De seguida identificamos alguns fatores que podem influenciar o sucesso escolar recorrendo para tal à regressão logística e à regressão ordinal. Concluímos que os alunos do sexo feminino, que residem num meio rural, com pouca dedicação ao estudo e falta de bases relativamente a anos anteriores manifestam mais dificuldades na aprendizagem. Além disso, concluímos também que os alunos com um mau ambiente familiar tendem a apresentar dificuldades que podem levar ao insucesso escolar

Symbolic-numeric interface: A review

A survey of the use of a combination of symbolic and numerical calculations is presented. Symbolic calculations primarily refer to the computer processing of procedures from classical algebra, analysis, and calculus. Numerical calculations refer to both numerical mathematics research and scientific computation. This survey is intended to point out a large number of problem areas where a cooperation of symbolic and numerical methods is likely to bear many fruits. These areas include such classical operations as differentiation and integration, such diverse activities as function approximations and qualitative analysis, and such contemporary topics as finite element calculations and computation complexity. It is contended that other less obvious topics such as the fast Fourier transform, linear algebra, nonlinear analysis and error analysis would also benefit from a synergistic approach

Experiencing War as the \u27Enemy Other\u27: Italian Scottish experience in World War II (Book Review) by Wendy Ugolini

Review of Experiencing War as the \u27Enemy Other\u27: Italian Scottish experience in World War II. Wendy Ugolini. Manchester: Manchester University Press, 2011. Pp. 288