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Selecting a small set of nodes called pivots, from all the nodes in a network and maintaining the routing infrastructure to and among each other can reduce routing overhead and excessive broadcast redundancy. In this paper a new problem, called "k-fold cover t- set" (for short, k-fold cover), is proposed: we select a smaller set of nodes than the k-fold dominating set, to act as alternative routers for messages in the network. An advantage of the k-fold cover is that it can be defined for graphs where the k-fold dominating set cannot be defined. Computing the minimum size k-fold cover for any k ges 1 is NP-complete. Two approximation algorithms for the k-fold cover problem are proposed: one uses a greedy approach to compute the cover and the other uses randomization.

Three 50 mm aperture model quadrupole magnets, designated as QSE-101 through 103, have been built at SSC Laboratory, two of which have have been tested at 4.25 K. The original concepts for the magnet and tooling design as well as assembly procedures have been evaluated in this program. Throughout this process, several magnet components were modified to improve the performance, reliability, and manufacturing of the magnet. The original magnet assembly procedures and design specific tooling were also evaluated and modified to accommodate fabrication of the model magnet. Fabrication and redesign of the model quadrupole magnet has resulted in good magnet performance as well as a more reliable, cost effective, and more production oriented magnet and tooling design. The new concepts which have emerged and the lessons learned from this effort are being applied to the design of magnets and tooling for the SSC Interaction Region quadrupoles as well as other SSC magnets which may be fabricated at the SSC. In this paper a discussion of the magnet and tooling design modifications, assembly processes, and the lessons learned during assembly and evaluation of QSE-101 through 103 is presented.

Industrial Computerized Tomography has been applied to magnet components in various stages of the manufacturing process. These Computerized Tomographic images can be analyzed to infer detailed dimensional information about magnet component positions (conductor, wedges, collars, etc.) throughout the magnet manufacturing process (cable winding, collaring, yoked/skinned). An analysis technique will be presented and measurement accuracies will be discussed.

The in process measurement system that is described below was designed to monitor the strain gauge instrumentation collar pack during all phases of quadrupole magnet manufacture. The primary goal was to implement a monitoring system that incorporated standard measurement techniques while maintaining signal integrity. The flexibility and robustness required in a production environment were taken into account throughout the design and implementation. All major components were chosen from commercially available supplies. The driving software was chosen to provide a user friendly interface while keeping software development efforts to a minimum without sacrificing adaptability.

Non-destructive digital photon transmission imaging can be performed with the IRIS™ system to provide internal component dimensions and locations of manufactured superconducting magnets and sub-assemblies. With non-destructive evaluation of the magnet components and sub-assemblies at critical stages of the manufacturing process, it is possible to assess the quality at each stage with the goal of improving manufacturing reproducibility and reliability. Evaluations of the feasibility of the IRIS™ system have been performed on a NbTi billet used for the production of monofilament rods used in the manufacturing of multifilament strand. The system has also been used to perform inspections on 40-mm and 50-mm collared coil sections and on cold masses. The dimensional accuracy for locating the conductor winding positions in a collared coil section has been found to be ±80 μm. Non-destructive analysis using the IRIS™ system offers examination capabilities in process and post-assembly inspection previously unavailable except through destructive physical analysis by sectioning and polishing for optical inspection after vacuum impregnation. This novel inspection tool may give us deep insights into the validity of our mechanical and electromagnetic models currently used to evaluate magnet design and may lead to substantial savings per magnet analysis.

The task of the legislator is indeed difficult when he has to consider and decide how far to extend the area to which the criminal law applies. The difficulty is most apparent in those forms of conduct which are seemingly directed towards some individual to whom civil law remedies are available, for then it must be asked whether these remedies are sufficient or if there is good reason for the addition of criminal sanctions.The usual considerations in this respect are many and various—has the normal victim of the harmful conduct the ways and means himself of resisting it without the assistance of the authorities; does the normal perpetrator of certain kinds of harmful conduct possess sufficient means which enable him to restore the status quo if civilly sued; is conduct of this kind highly frequent; does certain behaviour have a special temptation, which can only be fought by the deterrent force of a criminal sanction; and especially, does the public conscience regard this form of behaviour a serious infringement of public values that justifies and demands public punitive reaction, irrespective of the wishes of the injured person.

We have measured ultrasonic absorption in sinter-forged high Tc YBa2Cu3O7 − δ. Owing to the anisotropic properties of the sinter-forged samples, longitudinal ultrasonic attenuation measurements showed very strong anisotropy when waves were propagated parallel and perpendicular to the forging axis. Sound absorption was found to increase with decreasing temperature for shear waves travelling parallel to the forging axis.