India's software industry

India today has a distinct identity as a software superpower. With the world's second largest pool of English-speaking scientific and technical professionals, India boasts a US$5.7 billion software industry with an annual growth rate of more than 50 percent. As the software industry increasingly becomes a major driver of the nation's economy and policy makers devise ways to fuel its growth, India's software industry is poised for massive expansion. As a matter of fact, policy makers and industry leaders envision this industry's growing to more than US$80 billion by 2005 (with US$50 billion worth of software exports). The author considers India's competitive advantage and software competence. He gives a financial snapshot of India's software powerhouses     

Modeling of laser scanning system to determine its associated uncertainty of measurement

In the fabrication of fine wires such as filaments of lamps and optical fibers, it is always necessary to measure the diameter in real-time and correct the extrusion process. For metrological purposes, laser beam scanning technique will produce similar results as comparative to diffraction-assisted methods. A computerized laser beam scanning measurement system (LSM) is designed and fabricated. The LSM consists of a low power helium-neon gas laser source, a specially designed collimating lens, a hysteresis synchronous motor, a photo detector and a protective replaceable window along with temperature sensor. The LSM is mathematically modeled to identify various error contributing sources. The LSM is calibrated using a set of national reference standard cylindrical pins and a set of national reference standard slots to determine its relative calibration factor. The uncertainty of measurement achieved in the range of (0–35) mm is ± (0.55 +39.2L/m) μm.     

The influence of buoyant forces and volume fraction of particles on the particle pushing/entrapment transition during directional solidification of Al/SiC and Al/graphite composites

Directional solidification experiments in a Bridgman-type furnace were used to study particle behavior at the liquid/solid interface in aluminum metal matrix composites. Graphite or siliconcarbide particles were first dispersed in aluminum-base alloysvia a mechanically stirred vortex. Then, 100-mm-diameter and 120-mm-long samples were cast in steel dies and used for directional solidification. The processing variables controlled were the direction and velocity of solidification and the temperature gradient at the interface. The material variables monitored were the interface energy, the liquid/particle density difference, the particle/liquid thermal conductivity ratio, and the volume fraction of particles. These properties were changed by selecting combinations of particles (graphite or silicon carbide) and alloys (Al-Cu, Al-Mg, Al-Ni). A model which considers process thermodynamics, process kinetics (including the role of buoyant forces), and thermophysical properties was developed. Based on solidification direction and velocity, and on materials properties, four types of behavior were predicted. Sessile drop experiments were also used to determine some of the interface energies required in calculation with the proposed model. Experimental results compared favorably with model predictions. BRU K. DHINDAW Visiting Scholar with the Solidification Laboratory at the time this work was performed.     

Thermal stability characteristics of some resins from chemically modified PVC

PVC has been modified by chlorine displacement reaction with m-aminophenol, bisphenol A, and phenophthalein. Sulfonation of these condensates yields bifunctional weak acid resins which do not exhibit ? SO₃H ionogenic group. Reaction of PVC with presulfonated bisphenol A, phenolphthalein, and phenol yields strong acid resins. Thermal stability characteristics of these various resins have been determined and the results indicate that such modifications improve the overall thermal stability of PVC.