206519361
An Empirical Comparison of Data Flow and Mutation-Based Test Adequacy Criteria
Evaluation of the adequacy of a test set consisting of one or more test cases is a problem oftes encountered in software testing environments. Two test adequacy criiteria are considered, namely the data flow based all-uses criterion and a mutation based criterion. An empirical study was conducted to compare the ‘difficulty’ of satisfying the two criteria and their costs. Similar studies conducted in the past are discussed in the light of this study. A discussion is also presented of how and why the results of this study, when viewed in conjunction with the results of earlier comparisons of testing methods, are useful to a software test team.
30609851
An integrated solution for creating dependable software
Software testing and maintenance are the two most expensive phases of the software life cycle. Why, in general, are customers not satisfied with the quality of software? Studies have shown that approximately 20% of a software system is responsible for 80% of the faults and over the lifetime of an average software system as much as 70% of the cost is estimated to be dedicated to testing and maintenance. Clearly an appropriate methodology ought to be employed to address these high-leverage concerns. With the increased emphasis on software quality and the pressure to deliver software faster and cheaper such a methodology should encompass software design, architecture, development, testing, and maintenance as a whole and provide an integrated solution that leads to the creation of more dependable software. In addition, it is also crucial to have a set of effective tools with user-friendly interfaces available to software practitioners to apply this methodology in real-life contexts. We explain how to take advantage of sophisticated analysis of the dynamic behavior of the software being developed to help programmers, as well as testers, accomplish their assignments more effectively and efficiently.
31350744
Redesigning legacy systems into the object-oriented paradigm
Object-oriented/sup 1/ languages support many modern programming paradigms such as information hiding, inheritance, polymorphism, and dynamic binding. As a result, software systems implemented in OO languages are more reusable and reliable than those in non-OO. Many legacy software systems were created before OO programming became popular and needed to be redesigned and updated to OO programs. The process of abstracting OO designs from the procedural source code was often done manually or with limited assistance from program structural diagrams. Most reengineering focuses on the functionality of the original program, and the OO redesign often results in a completely new design based on the designers' understanding of the original program. Such an approach is not sufficient, for it not only takes time and effort for designers to become familiar with the original program, but the approach itself is also mistake-prone due to the human involvement. This paper presents a computer-aided semi-automatic method that abstracts OO designs from the original procedural source code. More specifically, it is a method for OO redesign based on program structural diagrams, visualization, and execution slice. We conducted a case study by applying this method to an inventory management software system. Results indicate that our method can effectively and efficiently abstract an appropriate OO design out of the original C code as well as re-generate part of the system in C++ code based on this new OO design.
206572113
Measuring distance between program features
We present a metric to determine the distance between the features of a software system. Such a measurement can elucidate how features of the system being examined are close to each other. We first use an execution slice-based technique to identify a set of code (basic blocks in our case) that is used to implement each feature. Then, depending on whether the execution frequency of each block is considered during the construction of such sets of code, a static as well as a dynamic distance is computed for each pair of features. These two types of distance differ in that the former computes the distance between two features only by how these features are implemented in the system, while the latter also takes into account how each feature is executed based on a user's operational profile. In other words, the static distance quantitatively gives the closeness of two features from the system implementation point of view, whereas the dynamic distance presents such closeness from the users' execution point of view. To illustrate the use of our metric, we report a case study on a Symbolic Hierarchical Automated Reliability and Performance Evaluator (SHARPE). The results of our study suggest that the distance metric discussed in this paper can provide a good measurement, in a quantitative way, of how close two program features are. Such information can also serve as a good start to understanding how a modification made to one feature is likely to affect other features.
39945640
Smart debugging software architectural design in SDL
Statistical data show that it is much less expensive to correct software bugs at the early design stage rather than the late stage of the development process when the final system has already been implemented and integrated together. The use of slicing and execution histories as an aid in software debugging is well established for programming languages like C and C++; however, it is rarely applied in the field of software design specification. We propose a solution by applying the source code level technologies to debugging software designs represented in a high-level specification and description language such as SDL. More specifically, we extend execution slice-based heuristics from source code-based debugging to the software design specification level. Suspicious locations in an SDL specification are prioritized by their likelihood of containing faults. Locations with a higher priority should be examined first rather than those with a lower priority as the former are more likely to contain the faults. A debugging tool, SmartD/sub DSL/, with user-friendly interfaces was developed to support our method. An illustration is provided to demonstrate the feasibility of using our method to effectively debug an architectural design.
16024151
An adaptable architecture for secure delivery of converged services
We present an approach for secure delivery of multimodal services to end users over heterogeneous converged networks. Our approach leads to an easily adaptable and extensible system architecture, in which system components interact with each other through loosely coupled interfaces based on asynchronous exchange of messages. It also effectively separates service logic from service delivery, through the introduction of a secure broker between the end user devices and the enterprise level application that contains the service logic. This separation also provides additional levels of security at the application level. This paper describes how our approach provides the features mentioned above. We have also validated our approach through the implementation of a prototype system, a description of which is also provided.
33298176
ORION: an adaptive home-based software distributed shared memory system
The authors describe a multithreaded software distributed shared memory, (DSM) system named Orion. It has been developed to provide a POSIX-thread (pthread) like interface. We believe this will avoid creating another unique set of application programming interfaces and ease the porting of pthread programs to a distributed environment. Orion implements a home based consistency model. We also present 2 adaptive schemes for home based DSM systems: home migration and dynamic adaptation between write-invalidation and require-update protocols. The two fully automatic schemes aim to involve minimal user intervention and yet deliver good performances with some speedups ranging from 2% to 79% observed in some 8 benchmarks tested.
10876551
Trilateral filtering for biomedical images
Filtering is a core operation in low level computer vision. It is a preliminary process in many biomedical image processing applications. Bilateral filtering has been applied to smooth biomedical images while preserving the edges. However, to avoid oversmoothing structures of sizes comparable to the image resolutions, a narrow spatial window has to be used. This leads to the necessity of performing more iterations in the filtering process. In this paper, we propose a novel filtering technique namely trilateral filter, which can achieve edge-preserving smoothing with a narrow spatial window in only a few iterations. The experimental results have shown that our novel method provides greater noise reduction than bilateral filtering and smooths biomedical images without over-smoothing ridges and shifting the edge locations, as compared to other noise reduction methods.
14960694
Comparative analysis of gene sets in the gene ontology space under the multiple hypothesis testing framework
The gene ontology (GO) resource can be used as a powerful tool to uncover the properties shared among, and specific to, a list of genes produced by high-throughput functional genomics studies, such as microarray studies. In the comparative analysis of several gene lists, researchers maybe interested in knowing which GO terms are enriched in one list of genes but relatively depleted in another. Statistical tests such as Fisher's exact test or Chi-square test can be performed to search for such GO terms. However, because multiple GO terms are tested simultaneously, individual p-values from individual tests do not serve as good indicators for picking GO terms. Furthermore, these multiple tests are highly correlated, usual multiple testing procedures that work under an independence assumption are not applicable. In this paper we introduce a procedure, based on false discovery rate (FDR), to treat this correlated multiple testing problem. This procedure calculates a moderately conserved estimator of q-value for every GO term. We identify the GO terms with q-values that satisfy a desired level as the significant GO terms. This procedure has been implemented into the GoSurfer software. GoSurfer is a windows based graphical data mining tool. It is freely available at http://www.gosurfer.org.
26732405
BaLinda Lisp: Design and Implementation
BaLinda Lisp is a parallel Lisp dialect employing a shared memory model of parallel processing together with a subset of the Linda tuple space operators. Also included in the design is speculative processing. The aim is to have shared memory multiprocessing with the tuple space acting as the main data structure through which synchronization is done. The result is a flexible programming language. In this paper, we shall describe the design philosophy of BaLinda Lisp, discuss its implementation on three multiprocessing platforms, give examples of programs written in BaLinda Lisp and discuss future work on the language.
13948106
Design of clocked circuits using UML
Clocking is an essential component of any embedded system design. However, traditional design techniques are either short of clocking support or too complex for users. The Unified Modeling Language (UML) has been proposed as design tool in real time system design, but the clocking semantics has not been properly dealt with. In this paper, we will present our experience of using UML to design a clocked system. In particular, UML is used to model the digital down converter, an essential component of software radios. Our tool chain automatically generates the simulation as well as synthesizes the final implementation.