Independent Configurable Architecture for Reliable Operation of Unmanned Systems with Distributed Onboard Services

This paper presents the development of ICAROUS-2 (Independent Configurable Architecture for Reliable Operation of Unmanned Systems with Distributed Onboard Services), the second generation of a software architecture that integrates several algorithms as distributed onboard services to enable robust autonomous UAS applications. In particular, the ICAROUS architecture defines a framework to perform detect and avoid, geofencing, path monitoring, path planning, and autonomous decision making to ensure safety and mission progress. Most of the core algorithms implemented in ICAROUS are formally verified using an interactive theorem prover. These algorithms are composed together using a plan execution engine, whose operational semantics is formally specified. A description of the integrated architecture, services currently available, and flight test results highlighting the capability of ICAROUS are presented

The digital data processing concepts of the LOFT mission

The Large Observatory for X-ray Timing (LOFT) is one of the five mission candidates that were considered by ESA for an M3 mission (with a launch opportunity in 2022 - 2024). LOFT features two instruments: the Large Area Detector (LAD) and the Wide Field Monitor (WFM). The LAD is a 10 m 2 -class instrument with approximately 15 times the collecting area of the largest timing mission so far (RXTE) for the first time combined with CCD-class spectral resolution. The WFM will continuously monitor the sky and recognise changes in source states, detect transient and bursting phenomena and will allow the mission to respond to this. Observing the brightest X-ray sources with the effective area of the LAD leads to enormous data rates that need to be processed on several levels, filtered and compressed in real-time already on board. The WFM data processing on the other hand puts rather low constraints on the data rate but requires algorithms to find the photon interaction location on the detector and then to deconvolve the detector image in order to obtain the sky coordinates of observed transient sources. In the following, we want to give an overview of the data handling concepts that were developed during the study phase.Comment: Proc. SPIE 9144, Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, 91446

Quantum Key Distribution

This chapter describes the application of lasers, specifically diode lasers, in the area of quantum key distribution (QKD). First, we motivate the distribution of cryptographic keys based on quantum physical properties of light, give a brief introduction to QKD assuming the reader has no or very little knowledge about cryptography, and briefly present the state-of-the-art of QKD. In the second half of the chapter we describe, as an example of a real-world QKD system, the system deployed between the University of Calgary and SAIT Polytechnic. We conclude the chapter with a brief discussion of quantum networks and future steps.Comment: 20 pages, 12 figure

A model-driven approach to broaden the detection of software performance antipatterns at runtime

Performance antipatterns document bad design patterns that have negative influence on system performance. In our previous work we formalized such antipatterns as logical predicates that predicate on four views: (i) the static view that captures the software elements (e.g. classes, components) and the static relationships among them; (ii) the dynamic view that represents the interaction (e.g. messages) that occurs between the software entities elements to provide the system functionalities; (iii) the deployment view that describes the hardware elements (e.g. processing nodes) and the mapping of the software entities onto the hardware platform; (iv) the performance view that collects specific performance indices. In this paper we present a lightweight infrastructure that is able to detect performance antipatterns at runtime through monitoring. The proposed approach precalculates such predicates and identifies antipatterns whose static, dynamic and deployment sub-predicates are validated by the current system configuration and brings at runtime the verification of performance sub-predicates. The proposed infrastructure leverages model-driven techniques to generate probes for monitoring the performance sub-predicates and detecting antipatterns at runtime.Comment: In Proceedings FESCA 2014, arXiv:1404.043

EMASS (trademark): An expandable solution for NASA space data storage needs

The data acquisition, distribution, processing, and archiving requirements of NASA and other U.S. Government data centers present significant data management challenges that must be met in the 1990's. The Earth Observing System (EOS) project alone is expected to generate daily data volumes greater than 2 Terabytes (2 x 10(exp 12) Bytes). As the scientific community makes use of this data, their work will result in larger, increasingly complex data sets to be further exploited and managed. The challenge for data storage systems is to satisfy the initial data management requirements with cost effective solutions that provide for planned growth. The expendable architecture of the E-Systems Modular Automated Storage System (EMASS(TM)), a mass storage system which is designed to support NASA's data capture, storage, distribution, and management requirements into the 21st century is described

Device-Centric Monitoring for Mobile Device Management

The ubiquity of computing devices has led to an increased need to ensure not only that the applications deployed on them are correct with respect to their specifications, but also that the devices are used in an appropriate manner, especially in situations where the device is provided by a party other than the actual user. Much work which has been done on runtime verification for mobile devices and operating systems is mostly application-centric, resulting in global, device-centric properties (e.g. the user may not send more than 100 messages per day across all applications) being difficult or impossible to verify. In this paper we present a device-centric approach to runtime verify the device behaviour against a device policy with the different applications acting as independent components contributing to the overall behaviour of the device. We also present an implementation for Android devices, and evaluate it on a number of device-centric policies, reporting the empirical results obtained.Comment: In Proceedings FESCA 2016, arXiv:1603.0837

Design and implementation of an integrative system for configurable exergames targeting the senior population

Exergames have been proposed as a solution for the promotion of physical activity in the senior population. The diversity of needs and limitations of the target users demand that the exergaming systems allow the configuration and adjustment of game parameters according to each user profile. Such systems are ideal to use in nursing homes, senior gymnasiums, or even rehabilitation centers. Health and sports professionals are then the main interacting users with the interface of such exergaming systems. Configuration can be difficult and time-consuming when considering complex systems with a significant amount of parameter choices. Since professionals working on such places already have time constraints, if they face long-time configuration of these systems they might give up of using them. Therefore, there is an evident need for systems that assist professionals in two ways. First, providing management support for training sessions and plans with exergames. Second, providing automatic decision-making processes that assist in game selection and parameters configuration to fit the user needs. The acceptance and effectiveness of such systems can only be achieved if the main prospective interactors with the system are involved in the development process so that the system can fulfill the users’ needs and expectations. This thesis reports on the design, implementation, and usability evaluation of an integrative system using some of the most-known human-centric techniques, such as interviews, card sorting, and paper prototyping. Results of a usability study of the UI and the main functionalities of the system showed a considerable acceptance and interest by the professionals. The usability study revealed to be a great resource to find aspects of the system that should be further considered for improvement in future iterations. Furthermore, the high results of the USE (Usefulness, Satisfaction, and Ease of use) questionnaire confirm that this system is a promising tool that sports professionals may be willing to use in their daily practice.A literatura suporta que os exergames, ou jogos que requerem exercício físico, constituem uma opção válida para promoção da atividade física na população idosa. A diversidade de necessidades e limitações do público-alvo exige que estes exergames sejam configuráveis de forma a permitir ajustar os parâmetros do jogo de acordo com o perfil de cada indivíduo. Estes sistemas personalizáveis são ideais para a utilização em lares, centros de dia, ginásios específicos para idosos ou até mesmo em centros de reabilitação. Os profissionais de saúde e de desporto são, assim, os principais utilizadores a definir as configurações destes exergames. Neste contexto, escolher as definições ideais para cada perfil pode ser um processo difícil e demorado, tendo em conta que a interface destes sistemas apresenta normalmente uma quantidade significativa de opções. Considerando que estes profissionais já têm constrangimentos de tempo na sua prática diária, se forem confrontados com uma interação longa e complexa com estes sistemas, podem acabar por desistir de usá-los. Neste sentido, existe uma clara necessidade de sistemas que auxiliem os profissionais a incluir os exergames na sua prática diária com a população idosa. Este sistema deverá assistir os profissionais de duas maneiras. Primeiro, que permita gerir sessões e planos de treino com os exergames. Segundo, que disponibilize processos de decisão automáticos de forma a auxiliar na escolha dos jogos, bem como nas configurações ideais para cada perfil de utilizador. A aceitação e a eficácia destes sistemas podem apenas ser alcançadas se os profissionais forem envolvidos no processo de desenvolvimento desde o início. Tal permitirá que este possa ser desenhado tendo em conta as suas necessidades e expectativas. Esta dissertação descreve as técnicas aplicadas no desenho, implementação e avaliação de um sistema integrativo para exergames, com base em algumas técnicas bem conhecidas na área de interação homemmáquina, como por exemplo entrevistas, card sorting e prototipagem em papel. Resultados de um estudo de usabilidade da interface do sistema integrativo demonstraram uma considerável aceitação e interesse por parte dos profissionais. O estudo de usabilidade revelou ser um bom recurso para encontrar aspetos do sistema que devem ser considerados para melhoramento em futuras iterações. Além disso, os resultados promissores do questionário USE (Utilidade, satisfação e facilidade de uso) confirmam que os profissionais poderão estar interessados em usar este sistema na sua prática diária

NETEMBED: A Network Resource Mapping Service for Distributed Applications

Emerging configurable infrastructures such as large-scale overlays and grids, distributed testbeds, and sensor networks comprise diverse sets of available computing resources (e.g., CPU and OS capabilities and memory constraints) and network conditions (e.g., link delay, bandwidth, loss rate, and jitter) whose characteristics are both complex and time-varying. At the same time, distributed applications to be deployed on these infrastructures exhibit increasingly complex constraints and requirements on resources they wish to utilize. Examples include selecting nodes and links to schedule an overlay multicast file transfer across the Grid, or embedding a network experiment with specific resource constraints in a distributed testbed such as PlanetLab. Thus, a common problem facing the efficient deployment of distributed applications on these infrastructures is that of "mapping" application-level requirements onto the network in such a manner that the requirements of the application are realized, assuming that the underlying characteristics of the network are known. We refer to this problem as the network embedding problem. In this paper, we propose a new approach to tackle this combinatorially-hard problem. Thanks to a number of heuristics, our approach greatly improves performance and scalability over previously existing techniques. It does so by pruning large portions of the search space without overlooking any valid embedding. We present a construction that allows a compact representation of candidate embeddings, which is maintained by carefully controlling the order via which candidate mappings are inserted and invalid mappings are removed. We present an implementation of our proposed technique, which we call NETEMBED – a service that identify feasible mappings of a virtual network configuration (the query network) to an existing real infrastructure or testbed (the hosting network). We present results of extensive performance evaluation experiments of NETEMBED using several combinations of real and synthetic network topologies. Our results show that our NETEMBED service is quite effective in identifying one (or all) possible embeddings for quite sizable queries and hosting networks – much larger than what any of the existing techniques or services are able to handle.National Science Foundation (CNS Cybertrust 0524477, NSF CNS NeTS 0520166, NSF CNS ITR 0205294, EIA RI 0202067