UNIX-derived operating systems have traditionally have a simplistic approach to process synchronization which is unsuited to multiprocessor application. Initial FreeBSD SMP support kept this approach by allowing only one process to run in kernel mode at any time, and also blocked interrupts across multiple processors, causing seriously suboptimal performance of I/O bound systems. This paper des...

Memory accesses contribute sunstantially to aggregate system delays. It is critical for designers to ensure that the memory subsystem is designed efficiently, and much work has been done on the exploitation of data re-use for algorithms that exhibit static memory access patterns in FPGAs. The proposed scheme enables the exploitation of data re-use for both static and non-static parallel memory ...

The fact that clustering is perhaps the most used technique for exploratory data analysis is only a semaphore that underlines its fundamental importance. The general problem statement that broadly describes clustering as the identification and classification of patterns into coherent groups also implicitly indicates it’s utility in other tasks such as supervised learning. In the past decade and...

Operating Systems have offered Locking as a de-facto mechanism for mutual exclusion. Locks have enjoyed widespread use due to their simplicity. However the burden of protecting a critical section is left to the programmer. Programmer has to ensure that the Locks are created, acquired, released and destroyed after use. Incorrect use of Locks can lead to race conditions. In Multi-programming, par...

 Teaching object-oriented programming in introductory computer courses is still an area not well understood by instructors and teachers. A new approach, quite different from the one used to teach the procedural paradigm, is required. We have developed and used for several years a teaching approach that is greatly influenced by constructivism, which stresses the importance of prior knowledge on...

This paper presents results on the complexity of computing event orderings for sharedmemory parallel program executions. Given a program execution, we formally define the problem of computing orderings that the execution must have exhibited or could have exhibited, and prove that computing such orderings is an intractable problem. We present a formal model of a shared-memory parallel program ex...

Real time computing is a wide open research area of intellectually challenging computer science problems with direct payoos to current technology. Real time systems have brought in huge challenges in a wide range of computer science disciplines, and each of those challenges must be met before the science of large scale real time systems can become a reality. This paper provides an overview of s...

We propose the formal study of governed blockchains that are owned and controlled by organizations and that neither create cryptocurrencies nor provide any incentives to solvers of cryptographic puzzles. We view such approaches as frameworks in which system parts, such as the cryptographic puzzle, may be instantiated with different technology. Owners of such a blockchain procure puzzle solvers ...

Reverse logistics is considered as a part of supply chain and can be minimized in the form of complaints received to strengthen the whole supply chain. Henceforth this paper attempts to analyze the gaps between identified defects and complaints received in ongoing production process through statistical analysis, which can be utilized further to minimize. A case study from a chemical industry ha...

Fast userlevel locking is an alternative locking mechanism to the typically heavy weight kernel approaches such as fcntl locking and System V semaphores. Here, multiple processes communicate locking state through shared memory regions and atomic operations. Kernel involvement is only necessary when there is contention on a lock, in order to perform queueing and scheduling functions. In this pap...