Multiprocessor compute servers have been available for many years now. It is expected that the number of cores and threads per processor chip will increase in the future. Hence, parallel programming will become more common. Posix-/Win32-Threads and OpenMP are the most wide-spread programming paradigms for shared-memory parallelization. At the first sight, programming for Posix-Threads or OpenMP may seem to be easily understandable. But for non-trivial applications, reasoning about the correctness ...
Tópico(s): Advanced Data Storage Technologies
2007 - Elsevier BV | Parallel Computing
The distinguishing feature of the Internet of Things is that many devices get interconnected. The threat of side-channel attacks in this setting is less understood than the threat of traditional network and software exploitation attacks that are perceived to be more powerful.This work is a case study of Thread, an emerging network and transport level stack designed to facilitate secure communication between heterogeneous IoT devices. We perform the first side-channel vulnerability analysis of the ...
Tópico(s): Security and Verification in Computing
2018 - | IACR Transactions on Cryptographic Hardware and Embedded Systems
The current definition of the Java bytecode verifier, as well as the proposals to formalize it, does not include any check about the structured use of locks by monitorenter and monitorexit instructions. So code is run, even if critical sections are corrupted. In this paper, we isolate a sublanguage of the Java Virtual Machine with thread creation and mutual exclusion. For this subset, we define a semantics and a formal verifier that enforces basic properties of threads and lock and unlock operations. ...
Tópico(s): Formal Methods in Verification
2002 - Elsevier BV | Theoretical Computer Science
Developing multi -core computer technology made it practical to accelerate image processing algorithms via parallel running threads.In this study, performance evaluations for parallel image convolution filter on a multicore computer using Java thread utilities was presented.For this purpose, the efficiency of static and the dynamic load scheduling implementations are investigated on a multi -core computer with six cores processor.Dynamic load scheduling overhead results were measured experimentally. ...
Tópico(s): Image Enhancement Techniques
2013 - | International Journal of Computer Applications
Abstract FairThreads introduces fair threads which are executed in a cooperative way when linked to a scheduler, and in a preemptive way otherwise. Constructs exist for programming the dynamic linking/unlinking of threads during execution. Users can profit from the cooperative scheduling when threads are linked. For example, data only accessed by the threads linked to the same scheduler does not need to be protected by locks. Users can also profit from the preemptive scheduling provided by the operating ...
Tópico(s): Real-Time Systems Scheduling
2005 - Wiley | Concurrency and Computation Practice and Experience
(1890). VIII. The elastic constants of quartz threads. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Vol. 30, No. 182, pp. 99-118.
Tópico(s): Seismic Waves and Analysis
1890 - Taylor & Francis | The London Edinburgh and Dublin Philosophical Magazine and Journal of Science
For concurrent programming to become mainstream, we must discard threads as a programming model. Nondeterminism should be judiciously and carefully introduced where needed, and it should be explicit in programs. In general-purpose software engineering practice, we have reached a point where one approach to concurrent programming dominates all others namely, threads, sequential processes that share memory. They represent a key concurrency model supported by modern computers, programming languages, ...
Tópico(s): Interconnection Networks and Systems
2006 - IEEE Computer Society | Computer
A thread is a basic unit of program execution that can share a single address space with other threads - that is, they can read and write the same variables and data structures. Originally, only assembly programmers used threads. A few older programming languages such as PL/I supported thread concurrency, but newer languages such as C and C++ use libraries instead. Only recently have programming languages again begun to build in direct support for threads. Java and Ada are examples of industry-strength ...
Tópico(s): Embedded Systems Design Techniques
2004 - IEEE Computer Society | Computer
Practical solution of the structural analysis problem in a parallel processing environment is investigated through the use of the notion of cheap concurrency and the concept of threads. A thread is a lightweight process or independent instructions executing agent capable of concurrent execution with other threads. Portions of a structural analysis code implemented in C have been parallelized employing the Encore Parallel Threads on an Encore Multimax multiprocessor computer. The issues of racing ...
Tópico(s): Logic, programming, and type systems
1989 - Wiley | Computer-Aided Civil and Infrastructure Engineering
Félix García, Javier Fernández,
Tópico(s): Multimedia Communication and Technology
2000 - Belltown Media | Linux journal
Online discussion forums are considered a challenging repository for data mining tasks.Forums usually contain hundreds of threads which in turn consist of hundreds, or even thousands, of posts.Clustering posts can be used to discover outlier and off-topic posts and would provide better visualization and exploration of online threads.In this paper, we propose the Leader-based Post Clustering (LPC), a modification to the Leader algorithm to be applied to the domain of clustering posts in threads of ...
Tópico(s): Data Visualization and Analytics
2011 - | International Journal of Computer Science and Information Technology
The worst-case execution time (WCET) of each real-time task in multicore processors with shared caches can be significantly affected by inter-thread cache interferences. The worst-case inter-thread cache interferences are dependent on how tasks are scheduled to run on different cores. Therefore, there is a circular dependence between real-time task scheduling, the worst-case inter-thread cache interferences, and WCET in multicore processors, which is not the case for single-core processors. To address ...
Tópico(s): Embedded Systems Design Techniques
2013 - | Journal of Computing Science and Engineering
Tópico(s): Currency Recognition and Detection
2016 - Engg Journals Publications | International Journal Of Engineering And Computer Science
Alexandra Hall, Jonathan Mendel,
The international ‘data war’ that is fought in the name of counter-terror is concerned with mobilising the uncertain future to intervene ‘before the terrorist has been radicalised’. Within this project, the digital footprint has become increasingly significant as a security resource. At the international border, particularly, the traces of data that cannot help but be left behind by everyday consumption and travel activity are mobilised within ‘smart’ targeting programmes to act against threat ahead ...
Tópico(s): Sex work and related issues
2012 - Routledge | Journal of Cultural Economy
Tópico(s): Formal Methods in Verification
2010 - Springer Science+Business Media | Lecture notes in computer science
John Regehr, Nathan Cooprider,
Most of the research effort towards verification of concurrent software has focused on multithreaded code. On the other hand, concurrency in low-end embedded systems is predominantly based on interrupts. Low-end embedded systems are ubiquitous in safety-critical applications such as those supporting transportation and medical automation; their verification is important. Although interrupts are superficially similar to threads, there are subtle semantic differences between the two abstractions. This ...
Tópico(s): Embedded Systems Design Techniques
2007 - Elsevier BV | Electronic Notes in Theoretical Computer Science
Gérard Boudol, Ilaria Castellani,
We propose a type system to ensure the property of noninterference in a system of concurrent programs, described in a standard imperative language enriched with parallelism. Our proposal is in the line of some recent work by Irvine, Volpano and Smith. Our type system seems more natural and less restrictive than that originally presented by these authors for the concurrent case. Moreover, we show how to extend the language in order to formalise scheduling policies for systems of sequential threads. ...
Tópico(s): Logic, programming, and type systems
2002 - Elsevier BV | Theoretical Computer Science
The authors investigate the dynamic scheduling of tasks with well-defined timing constraints. They present a dynamic uniprocessor scheduling algorithm with an O(n log n) worst-case complexity. The preemptive scheduling performed by the algorithm is shown to be of higher efficiency than that of other known algorithms. Furthermore, tasks may be related by precedence constraints, and they may have arbitrary deadlines and start times (which need not equal their arrival times). An experimental evaluation ...
Tópico(s): Distributed systems and fault tolerance
1992 - IEEE Computer Society | IEEE Transactions on Software Engineering
Abstract This paper embarks on a functional analysis of impolite language use in discussions about the response to the pandemic of Covid-19 on the official Facebook page of the Swedish national public television broadcaster in the spring of 2020. Having combined the existing models of impoliteness ( Culpeper 2016 ) with the Appraisal theory ( Martin and White 2005 ) in a both quantitative and qualitative investigation, the study finds remarkable differences between supporters and opponents of the Swedish ...
Tópico(s): Discourse Analysis in Language Studies
2022 - John Benjamins Publishing Company | Pragmatics Quarterly Publication of the International Pragmatics Association (IPrA)
We present a high-level Abstract State Machine (ASM) model of C ♯ threads and the .NET memory model. We focus on purely managed, fully portable threading features of C ♯ . The sequential model interleaves the computation steps of the currently running threads and is suitable for uniprocessors. The parallel model addresses problems of true concurrency on multi-processor systems. The models provide a sound basis for the development of multi-threaded applications in C ♯ . The thread and memory models complete ...
Tópico(s): Formal Methods in Verification
2005 - Elsevier BV | Theoretical Computer Science
Due to next-generation sequencing (NGS) technology, genome sequencing is able to process much more data at low cost. In NGS data analysis, the mapping of sequences into a reference genome takes the largest amount of time to process. Although the Burr
Tópico(s): Advanced Data Storage Technologies
2015 - IOS Press | Bio-Medical Materials and Engineering
Kuo‐Yang Tu, Zhan-Cheng Liang,
Particle Swarm Optimization (PSO) is an algorithm motivated by biological systems. However, PSO implementations are sequential, meaning that particles cannot simultaneously interact with other members in the same swarm. This study tries to develop an exact PSO model whose particles simultaneously interact with each other. To model limited communication capability, particles in a swarm are separated into several subgroups. Communication among the subgroups is implemented by parallel computation models ...
Tópico(s): Gene Regulatory Network Analysis
2010 - Elsevier BV | Expert Systems with Applications
We propose a novel online method of identifying the preferred NUMA nodes for objects with negligible overhead during the garbage collection time as well as object allocation time. Since the number of CPUs (or NUMA nodes) is increasing recently, it is critical for the memory manager of the runtime environment of an object-oriented language to exploit the low latency of local memory for high performance. To locate the CPU of a thread that frequently accesses an object, prior research uses the runtime ...
Tópico(s): Distributed systems and fault tolerance
2009 - Association for Computing Machinery | ACM SIGPLAN Notices
In a previous paper we used the backdrop of the Inca Empire for consideration of an appropriate locus for the discipline of informatics. The term informatics is used as a convenient umbrella term to stand for the overlapping disciplinary areas of Information Systems, Information Management and Information Technology. In this paper we consider one element from this case in more detail: that of the quipu. This enigmatic group of artefacts, consisting of complex assemblages of knotted cord, has been ...
Tópico(s): Data Visualization and Analytics
2009 - Elsevier BV | International Journal of Information Management
Michela Becchi, Patrick Crowley,
In a multi-programmed computing environment, threads of execution exhibit different runtime characteristics and hardware resource requirements. Not only do the behaviors of distinct threads differ, but each thread may also present diversity in its performance and resource usage over time. A heterogeneous chip multiprocessor (CMP) architecture consists of processor cores and caches of varying size and complexity. Prior work has shown that heterogeneous CMPs can meet the needs of a multi-programmed ...
Tópico(s): Cloud Computing and Resource Management
2008 - | The journal of instruction-level parallelism
Roberto M. Amadio, Silvano Dal Zilio,
We develop new methods to statically bound the resources needed for the execution of systems of concurrent, interactive threads. Our study is concerned with a synchronous model of interaction based on cooperative threads whose execution proceeds in synchronous rounds called instants. Our contribution is a system of compositional static analyses to guarantee that each instant terminates and to bound the size of the values computed by the system as a function of the size of its parameters at the beginning ...
Tópico(s): Interconnection Networks and Systems
2006 - Elsevier BV | Theoretical Computer Science
Current tools to analyze memory dumps of systems running Microsoft Windows usually build on the concept of enumerating lists maintained by the kernel to keep track of processes, threads and other objects. Therefore they will frequently fail to detect objects that are already terminated or which have been hidden by Direct Kernel Object Manipulation techniques. This article analyzes the in-memory structures which represent processes and threads. It develops search patterns which will then be used ...
Tópico(s): Security and Verification in Computing
2006 - Elsevier BV | Digital Investigation
Much of today’s software deals with multiple concurrent tasks. Web browsers support multiple concurrent HTTP connections, graphical user interfaces deal with multiple windows and input devices, and Web and DNS servers handle concurrent connections or transactions from large numbers of clients. The number of concurrent tasks that needs to be handled increases while software grows more complex. Structuring concurrent software in a way that meets the increasing scalability requirements while remaining ...
Tópico(s): Service-Oriented Architecture and Web Services
2005 - Association for Computing Machinery | Queue
Gregory Price, David K. Lowenthal,
The rising availability of multiprocessing platforms has increased the importance of providing programming models that allow users to express parallelism simply, portably, and efficiently. One popular way to write parallel programs is to use threads for concurrent sections of code. User-level threads packages allow programmers to implement multithreaded programs in which thread creation, thread management, and thread synchronization are relatively inexpensive. Fine-grain programs are multithreaded ...
Tópico(s): Advanced Data Storage Technologies
2003 - Elsevier BV | Journal of Parallel and Distributed Computing
Tópico(s): Real-Time Systems Scheduling
2000 - Springer Science+Business Media | Lecture notes in computer science