Applying Prolog to Develop Distributed Systems

Development of distributed systems is a difficult task. Declarative programming techniques hold a promising potential for effectively supporting programmer in this challenge. While Datalog-based languages have been actively explored for programming distributed systems, Prolog received relatively little attention in this application area so far. In this paper we present a Prolog-based programming system, called DAHL, for the declarative development of distributed systems. DAHL extends Prolog with an event-driven control mechanism and built-in networking procedures. Our experimental evaluation using a distributed hash-table data structure, a protocol for achieving Byzantine fault tolerance, and a distributed software model checker - all implemented in DAHL - indicates the viability of the approach

Coastal monitoring and feature estimation with small format cameras: application to the shoreline of Monte Hermoso, Argentina

Image and video processing of natural phenomena is one of the preferred non-invasive monitoring techniques for environmental studies that is, however, limited through the high cost of the required equipment and the limited access and precision of the processing algorithms. In this work we propose a low cost methodology for environmental studies using unexpensive off-the-shelf hardware and simple yet powerful processing algorithms. The images are taken using small format RGB cameras and processed in standard laptop equipments using open source libraries and processing algorithms specifically developed in general purpose programming languages. We applied this methodology to the coastal monitoring the shoreline of Monte Hermoso, Argentina, aimed at establishing accurate measurements of specific coastal features, for instance the coastal length. The experimental results show that our proposed unsupervised processing algorithm obtains results with a very high level of accuracy.VII Workshop Computación Gráfica, Imágenes y Visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

Toward an OSGi-Based Infra- structure for Smart Home Applications

[[abstract]]In this paper we show the steps to implement the prototype of a smart home environment, with emphasis on the OSGi framework and first-order logic based inference engine. Due to the inherent extensibility of the underlying system, either the interfaces of sensors/home appliances or the inference rules can be adjusted and reloaded during runtime. Moreover, we illustrate several sensor-driven services that may help develop intriguing smart home applications in the near future. Related works and future directions are also addressed to complete our current implementation afterwards.[[conferencetype]]國際[[conferencedate]]20090707~20090709[[iscallforpapers]]Y[[conferencelocation]]Brisbane, Australia

Monitoring Auditable Claims in the Cloud

When deploying mission-critical systems in the cloud, where deviations may have severe consequences, the assurance of critical decisions becomes essential. Typical cloud systems are operated by third parties and are built on complex software stacks consisting of e.g., Kubernetes, Istio, or Kafka, which due to their size are difficult to be verified. Nevertheless, one needs to make sure that mission-critical choices are made correctly. We propose a flexible runtime monitoring approach that is independent of the implementation of the observed system that allows to monitor safety and data-related properties. Our approach is based on combining distributed Datalog-based programs with tamper-proof storage based on Trillian to verify the premises of safety-critical actions. The approach can be seen as a generalization of the Certificate Transparency project. We apply our approach to an industrial use case that uses a cloud infrastructure for orchestrating unmanned air vehicles

An Analysis of Deductive-Query Processing Approaches for Logic Macroprograms in Wireless Sensor Networks

Logic macroprogramming paradigms for wireless sensor networks (WSNs) are rule-based abstractions for programming a network as a whole. Programmers only focus on the main objective of the network rather than the low-level implementation details on each node. Therefore, the low-level details are automatically handled by underlying middleware of the paradigms. To be viable, the middleware must efficiently handle the underlying issues as well as effectively minimize energy consumption and communication overhead. Not surprisingly, one major underlying issue in logic macroprogramming systems is deductive-query processing. In this paper, we analyze the characteristics of deductive-query processing and identify what have been overlooked in those previous approaches. Furthermore, we overview, analyze, and compare several recent approaches for deductive-query processing of logic macroprograms in WSNs. Our analysis reveals several important aspects that should be considered when designing such systems

Design and compilation of an object-oriented macroprogramming language for wireless sensor networks

open5siWireless sensor network (WSN) programming is still largely performed by experts in a node-centric way using low-level languages such as C. Although numerous higher-level abstractions exist, each simplifying a specific aspect of distributed programming, real applications often require to combine multiple abstractions into a single program. Using current programming frameworks, this represents a difficult task. In previous work, we therefore defined a conceptual framework that facilitates abstraction composition by defining sound compositional rules among few fundamental abstraction categories. The framework is extensible: programmers can add new abstractions within the boundaries determined by the compositional rules. In this paper we describe the design of a language - called MPL - that instantiates this conceptual framework. To support the extensible nature of the framework, the language is object-oriented, which allows programmers to add new abstractions by inheriting from existing classes that implement predefined interfaces. We modeled the syntax after Java, to make it more palatable to inexperienced embedded programmers. Compared to Java, we modified the language to enable efficient execution on WSN devices. We designed and implemented a compiler that translates MPL language into executable C code, which spares the overhead of a virtual machine. By comparing MPL implementations against functionally-equivalent Contiki/C implementations of several benchmark applications, we determined that the performance overhead of MPL is limited, and yet the programming task is simplified.openOppermann, Felix Jonathan; Römer, Kay; Mottola, Luca; Picco, Gian Pietro; Gaglione, AndreaOppermann, Felix Jonathan; Römer, Kay; Mottola, Luca; Picco, Gian Pietro; Gaglione, Andre

Coastal monitoring and feature estimation with small format cameras: application to the shoreline of Monte Hermoso, Argentina

Image and video processing of natural phenomena is one of the preferred non-invasive monitoring techniques for environmental studies that is, however, limited through the high cost of the required equipment and the limited access and precision of the processing algorithms. In this work we propose a low cost methodology for environmental studies using unexpensive off-the-shelf hardware and simple yet powerful processing algorithms. The images are taken using small format RGB cameras and processed in standard laptop equipments using open source libraries and processing algorithms specifically developed in general purpose programming languages. We applied this methodology to the coastal monitoring the shoreline of Monte Hermoso, Argentina, aimed at establishing accurate measurements of specific coastal features, for instance the coastal length. The experimental results show that our proposed unsupervised processing algorithm obtains results with a very high level of accuracy.VII Workshop Computación Gráfica, Imágenes y Visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

REED: Flexible rule based programming of wireless sensor networks at runtime

Wireless Sensor Networks (WSN) have emerged as an enabling technology for a variety of distributed applications. WSN middleware eases the development of these applications by providing a uniform programming environment. In this paper we present a rule based approach called REED (Rule Execution and Event Distribution) and describe how it supports flexible programming of WSNs at runtime. Indeed REED is required by the nature of its project setting to allow runtime programming. We demonstrate that by combining this runtime programmability with rules in an event, condition, action format we can support a range of paradigms, including Publish-subscribe and data aggregation algorithms. Current WSN middleware solutions have limited on-line programmability support so the applications cannot re-configure their WSNs while operational. Yet the runtime nature of the prototype requires both the distribution of rules and the events that trigger them so we also describe the rule management approach used to support the rule distribution; in particular a novel rule merging and filtering algorithm is described. The paper reports on the results gained from a REED prototype system constructed in our laboratory using Gumstix