Researchers have made a variety of empirical observations regarding the relative difficulty of various jobshop scheduling problems, but an understanding of why these problems are difficult remains elusive. Understanding difficulty ultimately requires an understanding the search space underlying a particular combination of problem instance and algorithm. In the case of local search algorithms, t...

Many WWW applications generate HTML or XML documents dynamically. Current tools, however, like languages using DOM or JAVA Server Pages do not allow to check the validity of the generated documents statically. Instead, validity has to be “checked” dynamically by appropriate test runs. This paper addresses this problem by introducing a new distinct class for each element type of a DTD. Each clas...

Measuring how features are actually used in a system has several potential benefits, for instance an improved requirements selection process. We have investigated how the use of features in Focal Point—a highly interactive, web-based RE tool—can be measured using log-file analysis, and we have interviewed key persons (user, developer, and consultant) in order to validate and discuss the deploye...

Caching web pages at proxies and in web servers' memories can greatly enhance performance. Proxy caching is known to reduce network load and both proxy and server caching can signiicantly decrease latency. Web caching problems have diierent properties than traditional operating systems paging , and cache replacement can beneet by recognizing and exploiting these diierences. We address two aspec...

Muscle pain is often experienced by workers who have to move repeatedly and/or forcibly. The cumulative trauma disorder that results from repetitive movements is difficult to anticipate and prevent. The present study uses a rodent model to: (1) determine the factors which produce dysfunctional muscles, (2) document changes in the matrix and myofibers which lead to pathologic muscles, and (3) st...

Since the discovery of the hepatitis C virus over 15 years ago, scientists have raced to develop diagnostics, study the virus and find new therapies. Yet virtually every attempt to dissect this pathogen has met with roadblocks that impeded progress. Its replication was restricted to humans or experimentally infected chimpanzees, and efficient growth of the virus in cell culture failed until ver...

Hepatitis C virus (HCV) will continue to be a serious global health threat for many years to come because of the chronic nature of the infection, its high prevalence and the significant morbidity of the resulting disease. Recently, a small number of molecules have produced encouraging results in proof-of-concept clinical trials. At the same time, preclinical evidence is accumulating that develo...

Working memory is a cognitive process that is responsible for temporarily holding and manipulating information. Most of the empirical neuroscience research on working memory has focused on measuring sustained activity in prefrontal cortex (PFC) and/or parietal cortex during simple delayed-response tasks, and most of the models of working memory have been based on neural integrators. But working...

Although cuckoo hashing has significant applications in both theoretical and practical settings, a relevant downside is that it requires lookups to multiple locations. In many settings, where lookups are expensive, cuckoo hashing becomes a less compelling alternative. One such standard setting is when memory is arranged in large pages, and a major cost is the number of page accesses. We propose...