33382273
Implementation of mixed current/voltage testing using the IEEE P1149.4 infrastructure
The development of a mixed-signal test bus infrastructure-IEEE P1149.4-is now in the final stages of the standardization process. Evaluating the test capabilities enabled by this infrastructure is an important step needed to support it as a well established standard. This paper presents experiments carried out with a test chip provided by the P1149.4 working group, which explore the architecture of the proposed analog boundary module to implement alternative testing methods. These include a method for parametric testing of passive components based on the monitoring of the power supply current, and a mixed current/voltage technique allowing the implementation of correlation for testing analog and mixed-signal macros.
37612228
An approach to testability improvement of mixed-signal boards
The increasing complexity of mixed-signal boards makes an integrated analogue/digital testability approach an attractive proposition. This paper investigates one such approach based on the use of mixed-signal test support ICs together with standard board level test infrastructures. The architecture of a test support IC and preliminary experimental results are also presented.<<ETX>>
14688474
A processor for testing mixed-signal cores in system-on-chip
This paper describes the design of a processor specific for testing cores embedded in system-on-chip. This processor, which can be implemented within a system's reconfigurable area, shall be responsible for scheduling and control test operations and perform preliminary data processing, as well as to provide the interface with an external tester. Building these test operations on-chip allows for simplifying external tester interface and to reduce testing time. The testing procedure and the infrastructure required to test an A/D converter is described as an example.
32609589
Avoiding checkpoint contamination in parallel systems
Checkpointing and rollback recovery is a very effective technique to tolerate faults, provided the application is able to recover from a previous checkpoint and proceed with a failure-free computation. However, this technique may fall short if the checkpoint files are somehow contaminated by errors. This paper presents two mechanisms that may be used to determine if a committed checkpoint is error-free or not. These techniques can be used simultaneously for error detection and failure recovery. Both of them are based on checkpoint duplication: one makes use of spatial redundancy while the other is based on temporal redundancy. We discuss the main problems and trade-offs that have to be dealt with to implement these techniques. We then present a performance study that clearly shows the pros and cons of each one. As far as we know, this paper presents the first implementation of these mechanisms in a standard parallel computing system.
5417799
Slicing XML Documents
Program slicing is a well-known technique to extract the program statements that (potentially) affect the values computed at some point of interest. In this work, we introduce a novel slicing method for XML documents. Essentially, given an XML document (which is valid w.r.t. some DTD), we produce a new XML document (a slice) that contains the relevant information in the original XML document according to some criterion. Furthermore, we also output a new DTD such that the computed slice is valid w.r.t. this DTD. A prototype implementation of the XML slicer has been undertaken.
17928832
Software Aging and Rejuvenation in a SOAP-based Server
Web-services and service-oriented architectures are gaining momentum in the area of distributed systems and Internet applications. However, as we increase the abstraction level of the applications we are also increasing the complexity of the underlying middleware. In this paper, we present a dependability benchmarking study to evaluate and compare the robustness of some of the most popular SOAP-RPC implementations that are intensively used in the industry. The study was focused on Apache Axis where we have observed a high susceptibility of software aging. Building on these results we propose a new SLA-oriented software rejuvenation technique that proved to be a simple way to increase the dependability of the SOAP-server, the degree of self-healing and to maintain a sustained level of performance in the applications
10139861
Dynamic slicing based on redex trails
Tracing computations is a widely used methodology for program debugging. Lazy languages, in particular, pose new demands on tracing techniques since following the actual trace of a computation is generally useless. Typically, they rely on the construction of a redex trail, a graph that describes the reductions of a computation and its relationships. While tracing provides a significant help for locating bugs, the task still remains complex. A well-known debugging technique for imperative programs is based on dynamic slicing, a method to find the program statements that influence the computation of a value for a specific program input.In this work, we introduce a novel technique for dynamic slicing in lazy functional logic languages. Rather than starting from scratch, our technique relies on (a slight extension of) redex trails. We provide a method to compute a correct and minimal dynamic slice from the redex trail of a computation. A clear advantage of our proposal is that one can enhance existing tracers with slicing capabilities with a modest implementation effort, since the same data structure (the redex trail) can be used for both tracing and slicing.
37459114
Cluster Analysis of Named Entities
This paper presents a statistics-based and language independent unsupervised approach for clustering possible named entities. We describe and motivate the features and statistical filters used by our clustering process. Using the Model-Based Clustering Analysis software we obtained different clusters of named entities. The method was applied to Bulgarian and English. For some clusters, precision is close to 100%; this helps human validation and saves time. Other clusters still need further refinement.