The algorithm of Cocke, Younger, and Kasami is a dynamic programming technique well-known from string parsing. It has been adopted to hypergraphs successfully by Lautemann. Therewith, many practically relevant hypergraph languages generated by hyperedge replacement can be parsed in an acceptable time. In this paper we extend this algorithm by hypergraph completion: If necessary, appropriate fre...

Cache is employed to exploit the phenomena of locality in many modern computer systems. One way of evaluating the impact of cache is to run a simulator on traces collected from realistic work load. However, for an important category of cache, namely those of random replacement policy, each round of the näıve simulation can only give one out of many possible results, therefore requiring many rou...

With the ever-growing performance gap between memory systems and disks, and rapidly improving CPU performance, virtual memory (VM) management becomes increasingly important for overall system performance. However, one of its critical components, the page replacement policy, is still dominated by CLOCK, a replacement policy developed almost 40 years ago. While pure LRU has an unaffordable cost i...

In a path-breaking paper last year Pat and Betty O'Neil and Gerhard Weikum proposed a self-tuning improvement to the Least Recently Used (LRU) buuer management algorithmm15]. Their improvement is called LRU/k and advocates giving priority to buuer pages based on the kth most recent access. (The standard LRU algorithm is denoted LRU/1 according to this terminology.) If P1's kth most recent acces...

Caching is one of the major steps in system designing to reach a higher performance in operating systems, databases and World Wide Web. High performance processors need memory systems with a proper access time, but still there is a big gap between performances of processors and memory systems. Virtual memory management and hierarchical memory models play an important role in system performance....

Water distribution networks (WDNs) comprise a complex network of pipes and are crucial for providing potable water to urban communities. Therefore, WDNs must be carefully managed avoid problems such as contamination service failures; however, this requires large budget. Because WDN components have different statuses depending on their installation year, location, transmission pressure, flow rat...

The butterfly optimization algorithm (BOA) is a swarm intelligence proposed in 2019 that simulates the foraging behavior of butterflies. Similarly, BOA itself has certain shortcomings, such as slow convergence speed and low solution accuracy. To cope with these problems, two strategies are introduced to improve performance BOA. One random replacement strategy, which involves replacing position ...