Results 251 to 260 of about 46,896 (292)

Distributed database concurrency controls using before-values

Proceedings of the 1981 ACM SIGMOD international conference on Management of data - SIGMOD '81, 1981
Associated with the write of a database entity is both the "before" or old value, and the "after" or new value. Concurrency can be increased by allowing other transactions to read the before values of a given transaction. The ramifications of allowing this, particularly on a distributed system in which limited communications is desirable, are ...
Richard E. Stearns, Daniel J. Rosenkrantz   +1 more
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Distributed autonomous control of concurrent combat tasks

Proceedings of the 2001 American Control Conference. (Cat. No.01CH37148), 2001
This article discusses the use of decentralized model predictive control to manage a set of related combat tasks (e.g., the destruction of anti-aerial defenses in a given geographical area by a wing of uninhabited air vehicles (UAV)). The controller is meant to operate autonomously as it attempts to manage conditions in which success in all its ...
Jorge E. Tierno, Ruth Kreichauf
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Distributed concurrency control with limited wait-depth

[1992] Proceedings of the 12th International Conference on Distributed Computing Systems, 2003
Distributed wait-depth-limited (DWDL) concurrency control, a locking-based method that limits the wait-depth of blocked transactions to one, which assures that deadlocks are resolved as part of regular transaction processing is described. The performance of DWDL is compared with that of distributed two-phase locking (2PL) and the wound-wait concurrency
P.A. Franaszek, J.R. Haritsa, J.T. Robinson, A. Thomasian   +3 more
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Concurrency control for distributed real-time databases

ACM SIGMOD Record, 1988
The concurrency control of transactions in a real-time database must satisfy not only the consistency constraints of the database but also the timing constraints of individual transactions. In this paper, we present a real-time concurrency control protocol that can be used in a distributed and decomposable real-time database.
Lui Sha, Ragunathan Rajkumar, John P. Lehooczky   +2 more
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Moderate Concurrency Control in Distributed Object Systems

Journal of Interconnection Networks, 2004
Objects are concurrently manipulated by multiple transactions in object-based systems. We newly introduce availability and exclusion types of conflicting relations among methods. Then, we define a partially ordered relation on lock modes showing which modes are stronger than others. We newly propose a moderate locking (ML) protocol.
Yohsuke Sugiyama, Tomoya Enokido, Makoto Takizawa   +2 more
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Resilient Concurrency Control in Distributed Database Systems

IEEE Transactions on Reliability, 1983
Summary: This paper presents the resiliency features of the optimistic approach to concurrency control and demonstrates how it lends itself to a design of a reliable distributed database system. The validation of concurrency control, integrity control, and atomicity control has been integrated. This integration provides a high degree of concurrency and
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Tree-Based Concurrency Control in Distributed Groupware

Computer Supported Cooperative Work (CSCW), 2003
We present a novel algorithm, called dARB, for solving the concurrency control problem in distributed collaborative applications. The main issue of concurrency control is resolving the conflicts resulting from simultaneous actions of multiple users. The algorithm reduces the need for manual conflict resolution by using a distributed arbitration scheme.
Mihail Ionescu, Ivan Marsic
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Distributed real-time optimistic concurrency control protocol

Proceedings of the 4th International Workshop on Parallel and Distributed Real-Time Systems, 2002
Although many recent studies have suggested that optimistic concurrency control (OCC) with dynamic adjustment of serialization order (DASO) is more suitable than two phase locking (2PL) for real-time database systems (RTDBS), most of the protocols proposed for DRTDBS are based on 2PL. When OCC with DASO is extended to DRTDBS, a number of issues have to
null Kwok-Wa Lam, V.C.S. Lee, null Kam-Yiu Lam, null Sheung-Lun Hung   +3 more
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Role-based concurrency control for distributed systems

20th International Conference on Advanced Information Networking and Applications - Volume 1 (AINA'06), 2006
A concept of role is widely and significantly used to design and implement secure information systems. A role shows a job function in an enterprise. In a role-based access control (RBAC) model, a role is a set of access rights. A subject doing a job is assigned with a role showing the job. In addition, a subject can play multiple roles in an enterprise.
T. Enokido, M. Takizawa
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Concurrency control protocol on distributed multimedia objects

18th International Conference on Advanced Information Networking and Applications, 2004. AINA 2004., 2004
Multimedia objects distributed in networks are concurrently manipulated by multiple transactions in applications like co-authoring systems. Not only state but also quality of service (QoS) of object is changed through methods. We define new types of conflicting and exclusive relations on methods to serialize transactions and to realize exclusive ...
K. Hasumi, T. Enokido, M. Takizawa
openaire   +1 more source