PaMS: A component-based service for finding the missing full text of articles cataloged in a digital library

Providing access to the full text of cataloged articles is a highly desirable feature for a digital library. However, in many such systems, not all metadata records have (a direct pointer to) a corresponding full-text document. In this article, we present PaMS: a new service for finding the missing full text of articles cataloged in a digital library. This service is implemented as a software component in order to be readily deployable to existing systems. It works as a parameterized meta-search engine and allows digital library administrators to easily set up a search strategy, i.e., a list of existing search engines to be queried for the missing full text, as well as the filtering and ranking policies to be applied to the results retrieved by each search engine. We evaluate our service with respect to its effectiveness and efficiency with collections from two distinct fields: computer science and biomedical and life sciences. Our results attest the effectiveness of PaMS for finding missing full-text documents as well as other relevant material while keeping its overall execution time at a reasonable level.     

Optimal Design of Piezoelectric Modal Transducers

Piezoelectric materials are those having the ability to convert electrical energy into mechanical one, and vice versa. Often surface bonded to structures, they are commonly used for sensing, acting and even for reducing noise and structural vibrations as part of active control systems. And, further, they can isolate specific mode shapes of structures when working as spatial filters in the frequency domain (i.e. modal transducers) by shaping properly the piezoelectric layers. This article is intended to revise that concept, initially conceived for beam-type structures only, and explain how it has been extended to plates and shells by means of optimization techniques.     

Practical Formulas for the Dimensioning of Air Valves

On the basis of theoretical considerations, the technical note presents two practical formulas for the dimensioning of air valves when filling a pipe with water. One is to be used for designing air valves on the basis of the maximum allowed water hammer overpressures; the other when the maximum in pipe water velocity is set. The reliability of these formulas was tested with a numerical model based on the same hypothesis, which was in turn verified with experimental tests.     

Natural and hybrid bimanual interaction for virtual assembly tasks

This paper focuses on the simulation of bimanual assembly/disassembly operations for training or product design applications. Most assembly applications have been limited to simulate only unimanual tasks or bimanual tasks with one hand. However, recent research has introduced the use of two haptic devices for bimanual assembly. We propose a more natural and low-cost bimanual interaction than existing ones based on Markerless motion capture (Mocap) systems. Specifically, this paper presents two interactions based on a Markerless Mocap technology and one interaction based on combining Markerless Mocap technology with haptic technology. A set of experiments following a within-subjects design have been implemented to test the usability of the proposed interfaces. The Markerless Mocap-based interactions were validated with respect to two-haptic-based interactions, as the latter has been successfully integrated into bimanual assembly simulators. The pure Markerless Mocap interaction proved to be either the most or least efficient depending on the configuration (with 2D or 3D tracking, respectively). Usability results among the proposed interactions and the two-haptic based interaction showed no significant differences. These results suggest that Markerless Mocap or hybrid interactions are valid solutions for simulating bimanual assembly tasks when the precision of the motion is not critical. The decision on which technology to use should depend on the trade-off between the precision requested to simulate the task, the cost, and inner features of the technology.     

Input disturbance suppression for a class of feedforward uncertain nonlinear systems

This paper deals with the problem of asymptotically rejecting bounded unknown disturbances affecting the input channel of a feedforward uncertain nonlinear system. The problem is solved assuming that the matched disturbance belongs to the class of signals generated by an autonomous neutrally stable exosystem whose state is not accessible. We design an internal model-based regulator capable on one hand to reject the matched disturbance for any initial state of the exosystem and, on the other hand, to robustly globally asymptotically stabilize the system using state feedback.     

Typed Mobile Ambients in Maude

Maude has revealed itself as a powerful tool for implementing different kinds of semantics so that quick prototypes are available for trying examples and proving properties. In this paper we show how to define in Maude two semantics for Cardelli and Gordon's Ambient Calculus. The first one is the operational (reduction) semantics which requires the definition of Maude strategies in order to avoid infinite loops. The second one is a type system defined by Cardelli and Gordon to avoid communication errors. The correctness of that system was not formally proved. We enrich the operational semantics with error rules and prove that well-typed processes do not produce such errors. The type system is highly non-deterministic. We show here one possible way of implementing such non-determinism in the rules.     

Reasoning about Object-based Calculi in (Co)Inductive Type Theory and the Theory of Contexts

We illustrate a methodology for formalizing and reasoning about Abadi and Cardelli’s object-based calculi, in (co)inductive type theory, such as the Calculus of (Co)Inductive Constructions, by taking advantage of natural deduction semantics and coinduction in combination with weak higher-order abstract syntax and the Theory of Contexts. Our methodology allows us to implement smoothly the calculi in the target metalanguage; moreover, it suggests novel presentations of the calculi themselves. In detail, we present a compact formalization of the syntax and semantics for the functional and the imperative variants of the ς-calculus. Our approach simplifies the proof of subject deduction theorems, which are proved formally in the proof assistant Coq with a relatively small overhead. Supported by UE project IST-CA-510996 Types and French grant CNRS ACI Modulogic.     

品质与创新是产品的关键

Fermax是一家拥有近60年历史的可视对讲产品制造厂商，产品供应全球市场，1995年该公司进入中国市场，凭借其在产品设计和品质上的突出表现，该品牌一直保持着市场领先的地位。面对当下众多本土厂商的竞争，以及产品被仿冒的不良市场行为，弗曼科斯（上海）电子有限公司董事长Alberto Maestre是如何思考的呢？     

Modular Structural Operational Semantics with Strategies

Strategies are a powerful mechanism to control rule application in rule-based systems. For instance, different transition relations can be defined and then combined by means of strategies, giving rise to an effective tool to define the semantics of programming languages. We have endowed the Maude MSOS Tool (MMT), an executable environment for modular structural operational semantics, with the possibility of defining strategies over its transition rules, by combining MMT with the Maude strategy language interpreter prototype. The combination was possible due to Maude's reflective capabilities. One possible use of MMT with strategies is to execute Ordered SOS specifications. We show how a particular form of strategy can be defined to represent an OSOS order and therefore execute, for instance, SOS specifications with negative premises. In this context, we also discuss how two known techniques for the representation of negative premises in OSOS become simplified in our setting.     

Prototype Platforms for Distributed Agreements

We present a prototype application for coordinating distributed agreements in multi-parties negotiations, where participants can dynamically join ongoing negotiations and where participants know only those parties they have interacted with. Our prototype is tailored to Ad-Hoc network scenarios involving the assignment of tasks for a rescue team operating over disaster areas. Our application is based on asynchronous communication and it exploits the d2pc protocol for committing or aborting a negotiation. Parties have been developed both in Jocaml+Perl and Polyphonic C. The implementation of the commit protocol allows components of both types to participate within the same negotiation.