12720907
XCS for robust automatic target recognition
A primary strength of the XCS approach is its ability to create maximally accurate general rules. In automatic target recognition (ATR) there is a need for robust performance beyond so-called standard operating conditions (SOCs, those conditions for which training data is available) to extended operating conditions (EOCs, conditions of known targets that cannot be foreseen and trained for). EOCs include things like vehicle-specific variations, environmental effects (mud, etc.), unanticipated viewing angles, and articulation of components of the target (hatches, turrets, etc.). This paper presents experiments where XCS addresses structural generalization over global and local features normally used in ATR classification. In many SOCs, these features are adequate for target recognition. Our goal with XCS is to form generalized rules that utilize these features for effective ATR in EOCs. Results show that XCS is effective in this generalization task. Conclusions and future directions for research are discussed.
6433216
XCS Applied To Mapping FPGA Architectures
This paper considers the application of XCS to the complex, real-world problem of mapping Boolean networks to technology-specific layout of field programmable gate arrays (FPGAs). The mapping is formulated as a temporal task, where the XCS's actions are to create blocks (based on an abstract Boolean network) that can be placed in the FPGA, one-at-a-time. Despite the complexity of this task, we demonstrate that the system is effective. We demonstrate the transfer of knowledge stored in an XCS rule set from a small FPGA mapping problem, to a larger problem. We present a novel technique that utilizes a problem-specific finite state machine and two populations of classifiers to treat the problem hierarchically. Final sections of the paper discuss implications and future directions for this work.
33919116
The Fighter Aircraft LCS: A Case of Different LCS Goals and Techniques
A system employed by the authors to acquire novel fighter aircraft manoeuvres from combat simulation is more akin to the traditional LCS model than to more recent systems. Given the difficulties often experienced in LCS research on simple problems, one must ask how a relatively primitive LCS has had consistent success in the complex domain of fighter aircraft manoeuvring. This paper presents the fighter aircraft LCS, in greater detail than in previous publications. Positive results from the system are discussed. The paper then focuses on the primary reasons the fighter aircraft LCS has avoided the difficulties of the traditional LCS. The authors believe the system's success has three primary origins: differences in credit assignment, differences in action encoding, and (possibly most importantly) a difference in system goals. In the fighter aircraft system, the goal has been simply the discovery of innovative, novel tactics, rather than online control. The paper concludes by discussing the most salient features of the fighter aircraft learning system, and how those features may be profitably combined with other LCS developments.
15267324
The Contract Net Protocol: High-Level Communication and Control in a Distributed Problem Solver
The contract net protocol has been developed to specify problem-solving communication and control for nodes in a distributed problem solver. Task distribution is affected by a negotiation process, a discussion carried on between nodes with tasks to be executed and nodes that may be able to execute those tasks.
11105386
Automated auditing of design principle adherence
Software design patterns and refactoring browsers are useful tools in developing high-quality software. Object-Oriented Oracle (OOO) is a tool that combines patterns and refactoring and extends them with the ability to recognize when the source-base doesn't adhere to software design principles. OOO relies on sophisticated compiler analyses and a set of heuristics to recognize characteristics of the code where a design principle is applicable, but is not being used. We present an example where the OOO can recognize noncompliance of design rules and the analyses and heuristics that are used to do the recognition. We also discuss other patterns where this approach applies and results from a prototype.
15470855
A field study of developer pairs: productivity impacts and implications
Pair programming purportedly delivers quality code with little productivity loss. The authors' field study, outside the pair programming environment, shows that two-person teams working independently are more productive than those working concurrently; agile methods may overcome inherent productivity losses of concurrent development. This research contrasts starkly with our field study findings. We decided to reexamine our earlier productivity data from teams of two and ask: Would our previous findings of concurrent-work productivity loss be reversed if we look only at programming pairs rather than teams of all sizes? If so, we could conclude that pairs are naturally more productive than larger teams, regardless of the collaborative process. If not, we could conclude that the collaboration mechanisms prescribed in pair programming might overcome a natural loss of productivity from concurrent work. We offer these findings and their implications as a benchmark against which we might measure the potential of pair programming practices.
226549
Using type enforcement to assure a configurable guard
Prior to the introduction of guard systems for electronic mail, guards tended to be overly specialized and not versatile enough for today's user community. The paper examines the use of type enforcement to create a highly assured yet administrator configurable guard. The administrator must be able to trust that the configuration provided will indeed be followed. This occurs by using highly assured or trusted components. These trusted components are then linked together via type enforcement to form a pipeline, with one input channel for data to enter the guard, and one separate, connected output channel for data to exit the guard. These channels are connected via assured processes whose behavior is restricted by the type enforcement mechanism. Furthermore, type enforcement is also used to isolate many components of the guard, which simplifies the assurance arguments. This technology is applied in the latest operational guards developed by the Secure Computing Corporation.
10260970
Pure adaptive search in global optimization
Pure adaptive seach iteratively constructs a sequence of interior points uniformly distributed within the corresponding sequence of nested improving regions of the feasible space. That is, at any iteration, the next point in the sequence is uniformly distributed over the region of feasible space containing all points that are strictly superior in value to the previous points in the sequence. The complexity of this algorithm is measured by the expected number of iterations required to achieve a given accuracy of solution. We show that for global mathematical programs satisfying the Lipschitz condition, its complexity increases at mostlinearly in the dimension of the problem.