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We examine a proposed test standard that can be used to evaluate the maximum representative change in linear dimensions of sheet encapsulation products for photovoltaic modules (resulting from their thermal processing). The proposed protocol is part of a series of material-level tests being developed within Working Group 2 of the Technical Committee 82 of the International Electrotechnical Commission. The characterization tests are being developed to aid module design (by identifying the essential characteristics that should be communicated on a datasheet), quality control (via internal material acceptance and process control), and failure analysis. Discovery and interlaboratory experiments were used to select particular parameters for the size-change test. The choice of a sand substrate and aluminum carrier is explored relative to other options. The temperature uniformity of ±5°C for the substrate was confirmed using thermography. Considerations related to the heating device (hot-plate or oven) are explored. The time duration of 5 minutes was identified from the time-series photographic characterization of material specimens (EVA, ionomer, PVB, TPO, and TPU). The test procedure was revised to account for observed effects of size and edges. The interlaboratory study identified typical size-change characteristics, and also verified the absolute reproducibility of ±5% between laboratories.

The prednisolone C-21 heteroaryl thioethers have been synthesized and evaluated in cell based transrepression and transactivation assays. Most of the compounds demonstrated weak transactivational activity in both human and rat tyrosineaminotransferase functional assay while keeping potent anti-inflammatory activity. The benzimidazole thioether 7 exhibited comparable anti-inflammatory activity and improved safety profile compared to the classical oral steroid prednisolone.

The creation of detailed virtual urban environments is an increasingly common task being faced by both the film and games industries. It is a time-consuming and expensive process that requires artists to model vast amounts of geometric detail, including terrain, roads, buildings and other associated features. We demonstrate a system that allows an artist to rapidly generate 3D cityscapes of arbitrary size, complexity and layout. This is achieved by means of an interactive interface that enables close control over key parameters while the system procedurally generates the required detail in real time. The results can be viewed and edited or exported in a format suitable for use in 3D modelling packages and game engines.

This paper addresses the issue of the reliability of modules using ultra-thin crystalline silicon cells. Do thin cells have a greater likelihood of cracking during production, transport, installation or use and if so does this result in long term degradation of the power? The present qualification test sequence, IEC 61215 does not adequately address this issue, The only mechanical test in IEC 61215 is a static mechanical load test consisting of three load cycles that are performed after the accelerated stress tests. So even if this mechanical load test does break cells, it is unlikely to result in significant power loss. BP Solar has developed a test sequence for evaluation of cracked cells in PV modules. The test sequence incorporates a dynamic mechanical load test performed before the 50 thermal cycles/10 humidity freeze cycles of IEC 61215. Usually there is no significant power loss after the dynamic load testing. However, the subsequent thermal cycling opens up the cracks that propagated during the dynamic load test resulting in significant power loss. Having a test sequence that identifies damaged cells allows us to develop processes and handling procedures to minimize or eliminate damage to the ultra-thin cells, resulting in reliable modules.

This paper will report on the BP Solar/Solarex efforts on polycrystalline silicon PV modules under the NREL/DOE PV Manufacturing Technology Program. BP Solar (previously Solarex) has been working on polycrystalline silicon PV technology under the NREL sponsored Photovoltaic Manufacturing Technology Program since 1993. This paper will review some of the major achievements of these programs. Results from a recently completed contract will be presented with emphasis on the development of processes and handling procedures for ultra-thin silicon wafers and cells. Finally the paper will conclude with a discussion of the future work planned in the present program.

Cells created from the division of the city by the primary road network form units of area upon which the secondary road generation component can operate. A technique similar to that used in the CityEngine [2001] based on L-systems can be applied for secondary road generation. The algorithm will be applied within each cell to create roads that service the land area by providing access to and from the primary road network. Global and local parameters for each cell can control the operation of the secondary road generation. Our system aims to provide an environment in which these parameters are easily accessible and a live preview is available. Buildings can be placed on the lots created by the enclosed regions from the secondary road generation. Building geometry will be constructed using L-systems taking several different building usage types into account including commercial, industrial, and residential with these usage types either stochastically assigned by the system or explicitly assigned by the user via the interactive interface. Real-Time rendering is possible in our design via the provision of a number of optimization features: city cell paging, level of detail and real-time geometry generation. City cell paging is a concept similar to terrain paging systems, the primary road network forms a skeleton for the city containing the generation parameters for the entire city partitioned into cells. The secondary road networks within each cell are paged andcan be pre-emptively generated and loaded on demand. Building structures stored as L-system strings can be parsed at run time to generate geometry. This provides a substantial reduction in memory usage by storing simple strings rather than complex geometry and also enables variants of buildings to be constructed depending on the parameters used for instantiation. A range dependent level of detail implementation can be constructed by including a parameter to specify the distance from camera to building and adjust the number of L-system iterations used accordingly. The implementation of our design is currently in progress. The interactive application has been built and the primary road generation component is complete, we expect to complete the final stages of the prototype in the next 6-8 months.

Medical professionals in nephrology are trained to think about improving quality and quantity of life with their patients, but only recently are they being urged to consider ways to improve end-of-life care. For many staff, this still feels contradictory. One nephrologist recently told these authors, "I was trained to help people live, not to help them die." The RWJF Promoting Excellence in End-of-Life Care work group has investigated, accumulated, and designed resources to help renal teams improve in this challenging arena. Peer mentoring is one such powerful resource, and, once in operation, is cost free. In conjunction with renal social work and the renal team, peer mentoring is a wonderful program that can decrease anxiety and preserve caring relationships in our burgeoning dialysis communities.

The objectives of this NREL sponsored Photovoltaic Manufacturing Technology (PVMaT) Program are to advance Solarex's cast polycrystalline silicon manufacturing technology, reduce module production cost in half, increase module performance and expand Solarex's commercial production capacity by a factor of three. To meet these objectives Solarex has: (1) modified the casting process and stations to grow larger ingots; (2) developed wire saws to cut wafers on as little as 400 /spl mu/m centers; (3) developed a laboratory process to increase cell efficiencies to 15% using back surface fields, mechanical texturing and gettering; (4) modified the casting, wires saw and cell processes in order to fabricate larger (15.2 cm by 15.2 cm) wafers and cells; (5) improved the automated assembly of modules, reducing labor requirements and increasing throughput; (6) developed a frameless module with a lower cost backsheet and a simple, low cost electrical termination system; and (7) determined the stress levels leading to wafer breakage and designed equipment for automated handling of thin wafers.

Realizing that the cost per channel of computerized scene generation would likely drop rapidly in the future and that the cost of visual projectors was similarly decreasing, the authors concluded that a full field-of-view display, consisting of many scene generation channels and projectors, could become economically feasible. Phase I of this project was tested by installing eight rear screen projectors on eight facets of a dodecahedron, and driving it with six channels of an existing scene generator. The result was a very bright, high-contrast display that has been most pleasing to all who have seen it. Phase II development attempts to increase resolution. While the resolution obtained in Phase I is sufficient for many tasks, it is inadequate for some air-to-ground weapon delivery tasks and longer range interaction with aircraft in air-to-air engagements. Phase II adds a two level of resolution, low cost, light weight, high resolution helmet mounted display. The result will be an affordable high performance display system.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The problem of voids and porosity has long plagued the dental technician. Many times an otherwise acceptable casting has had to be discarded because voids or porosities have developed within the casting. Because of numerous variables a technician often does not know the cause of the casting failure. Many investigators have studied variables that may affect the occurrence of voids and porosities.'-5 Asgar6 has conducted a study on the effects of sprue gauge, length, direction, shape, number of sprues, and flaring. He also studied the pressure of the casting machine and the amount of gold used when casting. He found that all of these variables have some effect on the occurrence of voids and porosities. Tucillo and Nielsen7 have reported that short, thick sprues tend to minimize local porosity but tend to form surface porosities. They found that the reverse was true with long, thin sprues. Brumfield8 recommended inserting a wax rod into the core of the investment when investing the pattern. In this way, gasses could leave the mold cavity in a short time and be free of voids and porosities. Strickland and Sturdevant9 say that "back pressure" porosity will be eliminated if a mold temperature of over 1,100 F is used. They have also found that the type of investment can be important in the elimination of "back pressure" porosity. Strickland and Sturdevant9 contend that varying the temperature of the casting alloy has no effect on "back pressure" porosity. Sprue size, oven burnout temperature, casting temperature of the gold, presence of a vent or heat sink, and type of investment are among the variables that confront the operator in casting. Small full crowns such as those on premolars are probably the castings most often destroyed by voids and porosities. By making over 200 castings using

The Handbook of Clinic Practice is a major surviving document that shows Dr. Kelly's early development as a clinician. The Handbook began as a guide for bachelor and master level students working in the Clinc. This was a major teaching tool for Dr. Kelly during his years at Fort Hays Kansas State College. It represents his early position regarding behavior in a clinical setting, and also provides a glimpse of the immense variety and scope of Dr. Kelly's talents.

The manuscript of which this issue is the first part, contains studies by nine graduate students made under the direction of Dr. George A. Kelly, Director of the Fort Hays State College Clinic, and consists of 243 pages. The manuscript will be published in three or four parts.