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The Standard Performance Evaluation Corporation (SPEC) CPU benchmark has been widely used as a measure of computing performance for decades. The SPEC is an industry-standardized, CPU-intensive benchmark suite and the collective data provide a proxy for the history of worldwide CPU and system performance. Past efforts have not provided or enabled answers to questions such as, how has the SPEC benchmark suite evolved empirically over time and what micro-architecture artifacts have had the most influence on performance? - have any micro-benchmarks within the suite had undue influence on the results and comparisons among the codes? - can the answers to these questions provide insights to the future of computer system performance? To answer these questions, we detail our historical and statistical analysis of specific hardware artifacts (clock frequencies, core counts, etc.) on the performance of the SPEC benchmarks since 1995. We discuss in detail several methods to normalize across benchmark evolutions. We perform both isolated and collective sensitivity analyses for various hardware artifacts and we identify one benchmark (libquantum) that had somewhat undue influence on performance outcomes. We also present the use of SPEC data to predict future performance. 

A better understanding of the inner structural features (watermarks and chain line/wire intervals) of the manuscript papers of Leonardo da Vinci (1452-1519) can provide valuable information regarding chronology, geographic origins, and studio practice. For valid conclusions, however, clear representations of watermarks and chain line/wires are required. While the easient way to capture these unique physical characteristics of paper is via transmitted light, they can be difficult to decipher when writing and other surface marks found on the recto (front/obverse) and the verso (back/reverse) of the sheet obscure them. Using Leonardo's Codex Leicester (Bill Gates Collection), complied circa 1508-1510, as a case study, a computational approach was designed to minimize surface writing to enhance the watermarks and chain lines/wires detectable in the paper, by subtracting out diffuse specular (normal) light images of the recto and verso sides from the transmitted light image. This is accomplished by posing the problem as a mathematical optimization problem, and solving for the optimal weights is fast and robust. 

We share approaches for coordinating the use of many online educational tools within a CS2 course, including an eTextbook, automated grading system, programming practice website, diagramming tool, and debugger. These work with other commonly used tools such as a response system, forum, version control system, and our learning management system. We describe a number of approaches to deal with the potential negative effects of adopting so many tools. To improve student success we scaffold tool use by staging the addition of tools and by introducing individual tools in phases, we test tool assignments before student use, and we adapt tool use based on student feedback and performance. We streamline course management by consulting mentors who have used the tools before, starting small with room to grow, and choosing tools that simplify student account and grade management across multiple tools.