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IEEE Software editor-in-chief Forrest Shull discusses the software sustainability and his interview with Girish Seshagiri, the CEO of AIS, an organization that offers "firm fixed-price contracting with performance guarantees, including a lifetime warranty on software defects" in government contracts. In addition, he discusses the best paper award at the 21st Annual IEEE International Requirements Engineering Conference and the best research paper award at the Agile Conference. The first Web extra at http://youtu.be/L1XN0R4koRk is an audio interview highlighting IEEE Software editor in chief Forrest Shull's discussion with Girish Seshagiri, the CEO of AIS, about the organization's philosophy of offering "firm fixed-price contracting with performance guarantees, including a lifetime warranty on software defects" in government contracts. The second Web extra at http://youtu.be/iFsZlrhSM9E is the complete audio interview in which IEEE Software editor in chief Forrest Shull's speaks with Girish Seshagiri, the CEO of AIS, about the organization's philosophy of offering "firm fixed-price contracting with performance guarantees, including a lifetime warranty on software defects" in government contracts. [ABSTRACT FROM PUBLISHER]

Objective: Reproducibility is the cornerstone of the scientific method. However, currently, many systems biology models cannot easily be reproduced. This paper presents methods that address this problem. Methods: We analyzed the recent Mycoplasma genitalium whole-cell (WC) model to determine the requirements for reproducible modeling. Results: We determined that reproducible modeling requires both repeatable model building and repeatable simulation. Conclusion: New standards and simulation software tools are needed to enhance and verify the reproducibility of modeling. New standards are needed to explicitly document every data source and assumption, and new deterministic parallel simulation tools are needed to quickly simulate large, complex models. Significance: We anticipate that these new standards and software will enable researchers to reproducibly build and simulate more complex models, including WC models. [ABSTRACT FROM PUBLISHER]

Objective: Only reproducible results are of significance to science. The lack of suitable standards and appropriate support of standards in software tools has led to numerous publications with irreproducible results. Our objectives are to identify the key challenges of reproducible research and to highlight existing solutions. Results: In this paper, we summarize problems concerning reproducibility in systems biology and systems medicine. We focus on initiatives, standards, and software tools that aim to improve the reproducibility of simulation studies. Conclusions: The long-term success of systems biology and systems medicine depends on trustworthy models and simulations. This requires openness to ensure reusability and transparency to enable reproducibility of results in these fields. [ABSTRACT FROM PUBLISHER]

This paper briefly summarizes software reuse research, discusses major research contributions and unsolved problems, provides pointers to key publications, and introduces four papers selected from The Eighth International Conference on Software Reuse (ICSR8). [ABSTRACT FROM AUTHOR]

A goal of runtime software-fault monitoring is to observe software behavior to determine whether it complies with its intended behavior. Monitoring allows one to analyze and recover from detected faults, providing additional defense against catastrophic failure. Although runtime monitoring has been in use for over 30 years, there is renewed interest in its application to fault detection and recovery, largely because of the increasing complexity and ubiquitous nature of software systems. This paper presents a taxonomy that developers and researchers can use to analyze and differentiate recent developments in runtime software fault- monitoring approaches. The taxonomy categorizes the various runtime monitoring research by classifying the elements that are considered essential for building a monitoring system, i.e., the specification language used to define properties; the monitoring mechanism that oversees the program's execution; and the event handler that captures and communicates monitoring results. After describing the taxonomy, the paper presents the classification of the software-fault monitoring systems described in the literature. [ABSTRACT FROM AUTHOR]

In the past few years, exception support for memory functions such as virtual memory, informing memory operations, software assist for shared memory protocols, or interactions with processors in memory has been advocated in various research papers. These memory traps may occur on a miss in the cache hierarchy or on a local or remote memory access. However, contemporary, dynamically scheduled processors only support memory exceptions detected in the TLB associated with the first-level cache. They do not support memory exceptions taken deep in the memory hierarchy. In this case, memory traps may be late, in the sense that the exception condition may still be undecided when a long-latency memory instruction reaches the retirement stage. In this paper we evaluate through simulation the overhead of memory traps in dynamically scheduled processors, focusing on the added overhead incurred when a memory trap is late. We also propose some simple mechanisms to reduce this added overhead while preserving the memory consistency model. With more aggressive memory access mechanisms in the processor we observe that the overhead of all memory traps--either early or late--is increased while the lateness of a trap becomes largely tolerated so that the performance gap between early and late memory traps is greatly reduced. Additionally, because of caching effects in the memory hierarchy, the frequency of memory traps usually decreases as they are taken deeper in the memory hierarchy and their overall impact on execution times becomes negligible. We conclude that support for memory traps taken throughout the memory hierarchy could be added to dynamically scheduled processors at low hardware cost and little performance degradation. [ABSTRACT FROM AUTHOR]

Nowadays, students can easily access online course materials at anytime or anywhere. Since the learning initiative is taken by students in an e-Iearning environment, student-centered course materials become more critical. They may be prepared based on an individual student's learning expectation and academic background. In this paper,.a model of personalized learning environment is proposed through 1) learning object design based on elaboration theory and e-learning standards; 2) applying item response theory (IRT) in student ability test; 3) managing course materials by a dynamic conceptual network (DCN); and 4) adopting a user profile to understand students' behaviors. Finally, these building blocks are developed by open-source software tools and integrated into a single system for real-life experimental study. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the design, implementation, and experimental evaluation of a middleware architecture for enabling Service Level Agreement (SLA)-driven clustering of QoS-aware application servers. Our middleware architecture supports application server technologies with dynamic resource management: Application servers can dynamically change the amount of clustered resources assigned to hosted applications on-demand so as to meet application-level Quality of Service (QoS) requirements. These requirements can include timeliness, availability, and high throughput and are specified in SLAs. A prototype of our architecture has been implemented using the open-source J2EE application server JBoss. The evaluation of this prototype shows that our approach makes possible JBoss' resource usage optimization and allows JBoss to effectively meet the QoS requirements of the applications it hosts, i.e., to honor the SLAs of those applications. [ABSTRACT FROM AUTHOR]

Developers of highly configurable performance-intensive software systems often use in-house performance-oriented "regression testing" to ensure that their modifications do not adversely affect their software's performance across its large configuration space. Unfortunately, time and resource constraints can limit in-house testing to a relatively small number of possible configurations, followed by unreliable extrapolation from these results to the entire configuration space. As a result, many performance bottlenecks escape detection until systems are fielded. In our earlier work, we improved the situation outlined above by developing an initial quality assurance process called "main effects screening." This process 1) executes formally designed experiments to identify an appropriate subset of configurations on which to base the performance-oriented regression testing, 2) executes benchmarks on this subset whenever the software changes, and 3) provides tool support for executing these actions on in-the-field and in-house computing resources. Our initial process had several limitations, however, since it was manually configured (which was tedious and error-prone) and relied on strong and untested assumptions for its accuracy (which made its use unacceptably risky in practice), This paper presents a new quality assurance process called "reliable effects screening" that provides three significant improvements to our earlier work. First, it allows developers to economically verify key assumptions during process execution. Second, it integrates several model-driven engineering tools to make process configuration and execution much easier and less error prone. Third, we evaluate this process via several feasibility studies of three large, widely used performance-intensive software frameworks. Our results indicate that reliable effects screening can detect performance degradation in large-scale systems more reliably and with significantly less resources than conventional techniques. [ABSTRACT FROM AUTHOR]

This paper extends an exponential reliability growth model to determine the optimal number of test cases to be executed for various use case scenarios during the system testing of software. An example demonstrates a practical application of the optimization model for system test planning. [ABSTRACT FROM AUTHOR]

Denormalized numbers are the most difficult type of numbers to implement in floating-point units. They are so complex that certain designs have elected to handle them in software rather than in hardware. Traps to software can result in long execution times, which renders denormalized numbers useless to programmers. This does not have to happen. With a small amount of additional hardware, denormalized numbers and underflows can be handled close to the speed of normalized numbers. This paper will summarize the little known techniques for handling denormalized numbers. Most of the techniques described here only appear in tiled or pending patent applications. [ABSTRACT FROM AUTHOR]

The investigation of processes of particle exchange and transport using filtration sampler, bottom water sampler, sediment traps, or other equipment is one important task in marine research. in this paper, we describe a modular hardware solution (microcontroller, flash memory, analog-to-digital converter, system interface) together with embedded software, which is suitable for event-triggered control of systems, which have to work autonomously for longer periods. The system developed is able to respond automatically to rapid changes at the bottom of the sea, because the decision control is available directly at runtime. [ABSTRACT FROM AUTHOR]

This paper demonstrates the usefulness and flexibility of parabolic equation methods when applied to high frequency (HF) propagation calculations over cliffs and in realistic arctic environments, which are required for estimating the performance of High Frequency Surface Wave Radar (HFSWR). All calculations are performed using a modified version of the TERPEM (TERrain Parabolic Equation Model) software package. This software has been tested extensively through comparisons with other models. As an example, a comparison between data generated with TERPEM and data published in the literature is shown. Calculations performed for four cliff heights (0, 102, 300, 498 m) show that the cliff does not significantly affect the propagation of HFSWR signals at the ranges of interest. Site-specific calculations performed for realistic arctic conditions (cold, low-salinity water covered with broken sea ice and snow) show that HFSWR propagation can be equal to or better than that for ice-free conditions over a significant range for a significant portion of the year (∼3 or 4 months). Based on these results, and other considerations related to sea clutter, ionospheric clutter, and man-made noise, it is concluded that useful operation of HFSWR at specific sites in the arctic should be feasible for a significant portion of the year. [ABSTRACT FROM AUTHOR]

This paper deals with a suppression method for the resonance oscillation in the ac side of a pulse-width modulation (PWM) current source converter. The converter is operated with the PWM switching pattern which is generated by the full digital control of computer software. The resonance current, caused by the LC low pass filter at the step change of the pattern, can be effectively suppressed by one pulse control of the pattern. The proposed method does not need to have the feedback loop of the current/voltage and does not offer the switching stress of the devices. The switching timing of the control is determined by pre-calculation of the off-line in consideration of the circuit constants. The experimental and the simulated results in the single-phase and the three-phase PWM converters are given, compared with those without the control, and show good response of the supply current. [ABSTRACT FROM AUTHOR]

The objective of this paper is to gain a better under standing of factors influencing software piracy. A model explaining the contribution of different factors to software piracy intention and its subsequent effect on actual software piracy is constructed based on established theories of human behavior. The model is then tested empirically in a longitudinal study with a survey. Findings show that social factors and beliefs concerning consequences of software piracy have significant effects on software piracy intentions. The data also show that while habits and facilitating conditions were significantly related to actual piracy behavior, intentions did not necessarily lead to the actual act of software piracy. The implications of the findings to research and practice are discussed. [ABSTRACT FROM AUTHOR]

This paper discusses the use of genetic algorithms (GAs) for automatic software test data, generation. This research extends previous work on dynamic test data generation where the problem of test data generation is reduced to one of minimizing a function [1], [2]. In our work, the function is minimized by using one of two genetic algorithms in place of the local minimization techniques used in earlier research. We describe the implementation of our GA-based system and examine the effectiveness of this approach on a number of programs, one of which is significantly larger than those for which results have previously been reported in the literature. We also examine the effect of program complexity on the test data generation problem by executing our system on a number of synthetic programs that have varying complexities. [ABSTRACT FROM AUTHOR]

The construction of software cost estimation models remains an active topic of research. The basic premise of cost modeling is that a historical database of software project cost data can be used to develop a quantitative model to predict the cost of future projects. One of the difficulties faced by workers in this area is that many of these historical databases contain substantial amounts of missing data. Thus far, the common practice has been to ignore observations with missing data. In principle, such a practice can lead to gross biases and may be detrimental to the accuracy of cost estimation models. In this paper, we describe an extensive simulation where we evaluate different techniques for dealing with missing data in the context of software cost modeling. Three techniques are evaluated: listwise deletion, mean imputation, and eight different types of hot-deck imputation. Our results indicate that all the missing data techniques perform well with small biases and high precision. This suggests that the simplest technique, listwise deletion, is a reasonable choice. However, this will not necessarily provide the best performance. Consistent best performance (minimal bias and highest precision) can be obtained by using hot-deck imputation with Euclidean distance and a z-score standardization. [ABSTRACT FROM AUTHOR]

This paper presents and evaluates a specification-based methodology for testing concurrent programs. This methodology requires sequencing constraints, which specify restrictions on the allowed sequences of synchronization events. Sequencing constraints for a concurrent program can be derived from the program's formal or informal specification. Details of the proposed testing methodology based on the use of Constraints on Succeeding and Preceding Events (CSPE) are given. How to achieve coverage and detect violations of CSPE constraints for a concurrent program, according to deterministic and nondeterministic testing of this program, are described. A coverage criterion for CSPE-based testing is defined and analyzed. The results of empirical studies of CSPE-based testing for four concurrent problems are reported. These results indicate that the use of sequencing constraints for specification-based testing of concurrent programs is a promising approach. [ABSTRACT FROM AUTHOR]

Experimentation in software engineering supports the advancement of the field through an iterative learning process. In this paper we present a framework for analyzing most of the experimental work performed in software engineering over the past several years. We describe a variety of experiments in the framework and discuss their contribution to the software engineering discipline. Some useful recommendations for the application of the experimental process in software engineering are included. [ABSTRACT FROM AUTHOR]

The article focuses on the percentage of software projects failure rates. The author has seen software failure trumpeted from so many academic research papers that he had to quit counting. However, if one closely examines the citations they use to support the claims of crisis, over and over again the citations boil down to one primary source, the Standish Chaos Reports. Those academic researchers who quote those original 1994 figures have ignored the fact that Standish has updated the Chaos Report periodically. The 2000 report, for example, saw a drop in cancelled projects to 23 percent, a small drop in challenged projects to 49 percent, and a corresponding increase in successful projects to 28 percent. Looking at other research studies of software failures, they discovered something interesting. Whereas Standish reported those 189 percent overruns, three other studies reported a consistent 33 to 34 percent cost overrun. Clearly, something was at best inconsistent between what Standish was doing and what the other three studies had learned.