A Formal Technique for Composing Cloud Services

Recent cloud search engines lack a formal method in their service composition mechanisms to automatically build composite services realizing user requirements. This paper prescribes behavior composition framework as a formal tools for the search engines. The framework automatically synthesizes a controller that delegates the service operations requested by a cloud user to the proper available cloud services whose operations satisfy the request. Since most cloud search engines support semantic and ontology to discover similar service operations, the paper extends the framework to be more adaptable with such search engines through the use of resource reasoning. Several experiments are provided to demonstrate how the extended framework outperforms the original one in terms of realizing users’ requirements.

A logic of hypothetical conjunction

A binary connective that can be read as a matching conjunction for conditional connectives found in many conditional logics is considered. The most natural way to read this connective is often as a conjunction and yet, hypothetically, considered to hold of a state of affairs that could be obtained under the hypothesis. The connective can be given an intensional semantics extending a standard semantics of conditional logic that uses propositionally indexed families of binary relations on possible worlds. This semantics is determined by an adjoint relationship between the operations supporting the semantics of the conditional and the new conjunction. The semantics of the hypothetical conjunction connective subsumes the semantics, supported by a ternary relation semantics, of the fusion connective that arises in connection with substructural and relevant logics, and therefore subsumes a number of other forms of conjunction. A number of applications of the hypothetical conjunction connective are discussed, including generalized forms of resource reasoning used in computer science applications.

On-Line Reconfigurable Machines

A recent trend in intelligent machines and manufacturing has been toward reconfigurable manufacturing systems, which move away from the idea of a fixed factory line executing an unchanging set of operations, and toward the goal of an adaptable factory structure. The logical next challenge in this area is that of on-line reconfigurability. With this capability, machines can reconfigure while running, enable or disable capabilities in real time, and respond quickly to changes in the system or the environment (including faults). We propose an approach to achieving on-line reconfigurability based on a high level of system modularity supported by integrated, model-based planning and control software. Our software capitalizes on many advanced techniques from the artificial intelligence research community, particularly in model-based domain-independent planning and scheduling, heuristic search, and temporal resource reasoning. We describe the implementation of this design in a prototype highly modular, parallel printing system.

On-Line Reconfigurable Machines

A recent trend in intelligent machines and manufacturing has been toward reconfigurable manufacturing systems, which move away from the idea of a fixed factory line executing an unchanging set of operations, and toward the goal of an adaptable factory structure. The logical next challenge in this area is that of on-line reconfigurability. With this capability, machines can reconfigure while running, enable or disable capabilities in real time, and respond quickly to changes in the system or the environment (including faults). We propose an approach to achieving on-line reconfigurability based on a high level of system modularity supported by integrated, model-based planning and control software. Our software capitalizes on many advanced techniques from the artificial intelligence research community, particularly in model-based domain-independent planning and scheduling, heuristic search, and temporal resource reasoning. We describe the implementation of this design in a prototype highly modular, parallel printing system.

Chain programs for writing deterministic metainterpreters

Many metainterpreters found in the logic programming literature are nondeterministic in the sense that the selection of program clauses is not determined. Examples are the familiar ‘demo’ and ‘vanilla’ metainterpreters. For some applications this nondeterminism is convenient. In some cases, however, a deterministic metainterpreter, having an explicit selection of clauses, is needed. Such cases include (1) conversion of OR parallelism into AND parallelism for ‘committed-choice’ processors, (2) logic-based, imperative-language implementation of search strategies, and (3) simulation of bounded-resource reasoning. Deterministic metainterpreters are difficult to write because the programmer must be concerned about the set of unifiers of the children of a node in the derivation tree. We argue that it is both possible and advantageous to write these metainterpreters by reasoning in terms of object programs converted into a syntactically restricted form that we call ‘chain’ form, where we can forget about unification, except for unit clauses. We give two transformations converting logic programs into chain form, one for ‘moded’ programs (implicit in two existing exhaustive-traversal methods for committed-choice execution), and one for arbitrary definite programs. As illustrations of our approach we show examples of the three applications mentioned above.