Abstract
Sensor networks can be viewed as a collection of tiny, low-cost devices programmed to sense the physical world and that communicate over radio links [12]. The devices are commonly called motes or smart dust [676], in allusion to their computational and sensing capabilities, as well as their increasingly small size. © 2009 Springer Berlin Heidelberg.

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Abstract
Prolog affords concise, elegant, and clean solutions for many interesting problems, but is not immune to the software engineering challenges of large-scale application development. Code modularization, using modules or objects, is a key feature to keep projects manageable. Since most literature, instruction, and practice focus exclusively on object-oriented languages derived from imperative languages, objects are perceived as alien to logic programming while modules are considered a natural fit. Logtalk is an object-oriented logic programming language that can use most Prolog implementations as a back-end compiler. Logtalk objects are about code encapsulation and reuse, providing an alternative to Prolog module systems, and enabling natural solutions for a wide range of problems that would be awkward to solve using modules. This talk presents the Logtalk design goals, followed by a tutorial on Logtalk programming and some application examples. The talk ends with a discussion on the problems and benefits of developing Logtalk as a portable Prolog application. © 2009 Springer Berlin Heidelberg.

Abstract
This paper presents a survey of programming patterns for Logtalk parametric objects. A parametric object is an object whose identifier is a compound term containing logical variables. These variables play the role of object parameters. Object predicates can be coded to depend on the parameter values. Parametric objects are a common feature of some other object-oriented logic programming languages and Prolog object-oriented extensions. Logtalk extends the usefulness of parametric objects by introducing the concept of object proxies. An object proxy is a compound term that can be interpreted as a possible instantiation of the identifier of a parametric object. Object proxies, when represented as predicate facts, allow application memory footprint to be minimized while still taking full advantage of Logtalk object-oriented features for representing and reasoning with taxonomic knowledge. © 2011 Springer-Verlag Berlin Heidelberg.

Abstract
This paper identifies potential security loopholes in the implementation of support for meta-predicates Closing these loopholes depends on three conditions: a clear distinction between closures and goals, support for an extended meta-predicate directive that allows the specification of closures, and the availability of the call/2-N family of built-in meta-predicates. These conditions provide the basis for a set of simple safety rules that allows meta-predicates to be securely supported. These safety rules are currently implemented by Logtalk, all object-oriented logic programming language, and may also be applied in the context of Prolog predicate-based module systems. Experimental results illustrate how these rules can prevent several security problems, including accidental or malicious changes to the original meta-predicate arguments and bypassing of predicate scope rules and predicate scope directives.