the proceedings contain 18 papers. the special focus in this conference is on Querying and Query Optimisation. the topics include: Semistructured computation;on the power of incremental evaluation in SQL-like language...
ISBN:
(纸本)3540414819
the proceedings contain 18 papers. the special focus in this conference is on Querying and Query Optimisation. the topics include: Semistructured computation;on the power of incremental evaluation in SQL-like languages;optimization of nested SQL queries by tableau equivalence;user-defined aggregates in database languages;how to make SQL stand for string query language;structured document transformations based on XSL;extensions of attribute grammars for structured document queries;a component-based paradigm for data source integration;defining and handling transient fields in PJama;a framework for optimizing distributed workflow executions;querying semistructured data based on schema matching;union types for semistructured data;query optimization for semistructured data using path constraints in a deterministic data model;expressing topological connectivity of spatial databases;a representation independent language for planar spatial databases with euclidean distance;an abstract interpretation framework for termination analysis of active rules;on the difference between navigating semi-structured data and querying it and integrating structured and semistructured data .
this paper describes a native ATM support for CORBA. Our system provides three advanced features. the first feature is to extend the CORBA interface to explicitly support network bandwidth reservation provided by ATM....
详细信息
ISBN:
(纸本)0769509304
this paper describes a native ATM support for CORBA. Our system provides three advanced features. the first feature is to extend the CORBA interface to explicitly support network bandwidth reservation provided by ATM. the second feature is to support the negotiation between a client and a server to reserve network bandwidth. the last feature is to support multiple transport protocols simultaneously. Our system allows a programmer to select either IIOP to invoke methods in a best effort way or GIOP over ATM for timing critical invocations.
In this paper we demonstrate how a default theory, expressed through a set of conditional defaults that the agent possesses, can be traduced into extended logic programs. Additionally, the proposed trans-lation allows...
详细信息
Guarded logics are fragments of first-order logic, fixed point logic or second-order logic in which all quantifiers are relativised by guard formulae in an appropriate way. Semantically, this means that such logics ca...
详细信息
ISBN:
(纸本)3540412859
Guarded logics are fragments of first-order logic, fixed point logic or second-order logic in which all quantifiers are relativised by guard formulae in an appropriate way. Semantically, this means that such logics can simultaneously refer to a collection of elements only if all these elements are ‘close together’ (e.g. coexist in some atomic fact). Guarded logics are powerful generalizations of modal logics (such as propositional multi-modal logic or the modal μ-calculus) that retain and, to a certain extent, explain their good algorithmic and model-theoretic properties. In this talk, I will survey the recent research on guarded logics. I will also present a guarded variant of Datalog, called Datalog LITE, which is semantically equivalent to the alternation-free portion of guarded fixed point logic. the main focus of the talk will be on model checking (or equivalently, query evaluation) algorithms for guarded *** the complexity of evaluating arbitrary guarded fixed point formulae is closely related to the model checking problem for the modal μ-calculus (for which no polynomial-time algorithms are known up to now), there are interesting fragments that admit efficient, in fact linear time, evaluation algorithms. In particular this is the case for the guarded fragment of first-order logic and for Datalog LITE.
Alpha-Beta is a well known optimized algorithm used to compute the values of classical combinatorial games, like chess and checkers. the known proofs of correctness of Alpha-Beta do rely on very specific properties of...
详细信息
the priority inversion problem has been detected two decades ago. the decisive ideas to cope withthis problem have been published one decade ago. In the meantime the vendors of operating systems and run-time systems ...
详细信息
ISBN:
(纸本)0769509304
the priority inversion problem has been detected two decades ago. the decisive ideas to cope withthis problem have been published one decade ago. In the meantime the vendors of operating systems and run-time systems have occupied this topic in providing certain protocols in order to avoid priority inversion. However, at a closer look there are considerable differences in the usage and the results of the various protocol interfaces. this is really pitiful in the scope of real-time systems, because the application programmer wants to rely on certain predictability criterions, depending only on the kind of protocol used. Hence, we propose test-suites to check the degree of conformance between the protocol proposed in literature and the one implemented in a certain environment.
this paper is focused on the performance analysis;sis, comparison and optimization of the most important distributed object models for Java: RMI (Remote Method Invocation) and RMI-IIOP (Remote Method invocation over I...
详细信息
ISBN:
(纸本)0769505686
this paper is focused on the performance analysis;sis, comparison and optimization of the most important distributed object models for Java: RMI (Remote Method Invocation) and RMI-IIOP (Remote Method invocation over Internet Intel-ORB Protocol). the paper presents the following contributions to the research on distributed object performance. First, a detailed performance analysis of both models is provided withthe in-depth comparison. these results help to understand how the models perform, Second, an overhead analysis and the bottleneck identification is presented withthe explanation why there are differences in performance. third, optimizations and the results for performance improved post-beta RMI-IIOP versions are presented. these show considerably beta performance in all areas compared to the original beta release, with RMI-IIOP having equivalent or better performance to RMI in almost all cases.
this paper presents a new framework for constructing flexible event-driven systems for distributed networked devices and appliances, referred to as Dragon. Dragon enables constructing and modifying an event-driven sys...
详细信息
ISBN:
(纸本)0769509304
this paper presents a new framework for constructing flexible event-driven systems for distributed networked devices and appliances, referred to as Dragon. Dragon enables constructing and modifying an event-driven system easily by visualizing distributed services which are handled in an integrated manner. the update of the system is conducted immediately following a modification by Dragon. Dragon is built on to of Jini/Java and can. be executed on any Jini/Java-compliant machines. In addition, Dragon incorporates soft real-time event delivery to enhance the predictability of behavior of the constructed system. In. this paper, we describe in detail of design and implementation of Dragon.
To develop the applications for Internet appliances, embedded software development tools need various host tools such as cross compilers and binary utilities as well as a remote debugger, an interactive shell, and rea...
详细信息
ISBN:
(纸本)0769509304
To develop the applications for Internet appliances, embedded software development tools need various host tools such as cross compilers and binary utilities as well as a remote debugger, an interactive shell, and real-time resource monitors. the heavy host-target communication overhead and inconsistency caused by various host tools make target monitor programs more complex. In this paper, we propose a debugging protocol for these tools that supports several host-resident tools under the existence of RTOS. To abstract the details of the target systems, we have developed a target agent running as a task on the RTOS. Target agent is the counterpart of host agent that supports host tools through the communication over UDP/IP. the proposed architecture is implemented and tested on Esto (Embedded Systems Toolset), a development tool for Internet-based embedded applications.
there is art increasing demand for methods that calculate the worst case execution rime (WCET) of real-time programs. the calculations are typically based on path information for the program, such as the maximum numbe...
详细信息
ISBN:
(纸本)0769509304
there is art increasing demand for methods that calculate the worst case execution rime (WCET) of real-time programs. the calculations are typically based on path information for the program, such as the maximum number of iterations in loops and identification of infeasible paths. Most often, this information is given as manual annotations by the programmer. Our method calculates path information automatically for real-time programs, ther ebv relieving the programmer from tedious and error-prone work. the method, based on abstract interpretation, generates a safe approximation of the path information. A trade-of between quality and calculation cost is made, since finding the exact information is a complex, often intractable problem for nontrivial programs. We describe the method by a simple, worked example. We show that our prototype tool is capable of analyzing a number, of program examples from the WCET literature, without using any extra information or consideration of special cases, needed in other approaches.
暂无评论