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By harnessing the computational power of distributed heterogeneous resources, it is possible to build a large scale integrated system so that a centralized program is partitioned and distributed across those resources in a way that maximizes the system's overall utility. However, building such a system is a staggering challenge because of the associated complexities. This paper proposes a selfmanaging distributed system ADE, that incorporates autonomic entities to handle the complexities associated with distribution, coordination and efficient execution of program components. The proposed approach models a centralized application in terms of an application graph consisting application components and then deploys the application components across the underlying hierarchically organized distributed resources so that all constraints and requirements are satisfied and the system's overall utility is maximized. Then, based on the observations obtained by the monitoring of the system resources, ADE redeploys the application graph to maintain maximized system utilization in spite of the dynamism and uncertainty involved in the system.

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A goniometer is an instrument which is frequently used in optics and other branches of physics. It enables the study of light scattered in various directions from a solid, liquid or powdered sample. The goniometric instruments that are already available on the market are designed for a specific purpose and are quite costly. Fully-computerized devices—which automatically acquire data and control the positions of the light source and detector—are even more expensive. In this work, the instrumentation of a self-fabricated, low cost, but fully computerized goniometric instrument designed for studying a light-scattering problem in planetary science is described in detail. This device uses Arduino microcontroller boards for acquiring data, and stepper motors are employed for automated control of the positions of the light source and detector. A low-cost but high-intensity laser diode was used as the light source, and a very sensitive photodiode integrated circuit was used as the light detector. This work has a pedagogical value in the sense that the reader will benefit from learning about the techniques used, the components and their calibration, the software, etc. More importantly, the cost-effectiveness of this work may be beneficial to many experimentalists and instrument designers working in this field, to control their project budgets.