5,015 research outputs found
Length-weight relationships of demersal fishes from the upper continental slope off Colombia
Parameters of the length–weight relationship of the form W=aLb are presented for 45 demersal fish species caught on the upper continental slope of the Caribbean Sea off Colombia. The b values varied between 2.13 and 4.97, with the mean b = 3.042 (95% CI, 2.887- 3.196)
A Change Execution System for Enterprise Services with Compensation Support
Modern enterprises rely on a distributed IT infrastructure to execute their business processes, adopting Service Oriented Architectures in order to improve the flexibility and ease of adaptation of their functions. Nowadays this is a vital characteristic, as the increased competition forces companies to continuously evolve and adapt. SOA applications must be supported by management and deployment systems, which have to continuously apply modifications to the distributed infrastructure. This article presents a modelbased solution for automatically applying change plans to heterogeneous enterprise managed environments. The proposed solution uses models which describe in an abstract language the changes that need to be applied to the environment, and executes all the required operations to the specific managed elements. Also, to ensure that the environment ends in a stable state, compensation for previously executed operations is supported. The validation results from a case study taken from the banking domain are also presented here
Detector blinding attacks on counterfactual quantum key distribution
Counterfactual quantum key distribution protocols allow two sides to
establish a common secret key using an insecure channel and authenticated
public communication. As opposed to many other quantum key distribution
protocols, part of the quantum state used to establish each bit never leaves
the transmitting side, which hinders some attacks. We show how to adapt
detector blinding attacks to this setting. In blinding attacks, gated avalanche
photodiode detectors are disabled or forced to activate using bright light
pulses. We present two attacks that use this ability to compromise the security
of counterfactual quantum key distribution. The first is a general attack but
technologically demanding (the attacker must be able to reduce the channel loss
by half). The second attack could be deployed with easily accessible technology
and works for implementations where single photon sources are approximated by
attenuated coherent states. The attack is a combination of a photon number
splitting attack and the first blinding attack which could be deployed with
easily accessible technology. The proposed attacks show counterfactual quantum
key distribution is vulnerable to detector blinding and that experimental
implementations should include explicit countermeasures against it
A Model-Based Approach for the Management of Electronic Invoices
The globalized market pushes companies to expand their business boundaries to a whole new level. In order to efficiently support this environment, business transactions must be executed over the Internet. However, there are several factors complicating this process, such as the current state of electronic invoices. Electronic invoice adoption is not widespread because of the current format fragmentation originated by national regulations. In this paper we present an approach based on Model-Driven Engineering techniques and abstractions for supporting the core functions of invoice management systems. We compare our solution with the traditional implementations and try to analyze the advantages MDE can bring to this specific domain
An automated Model-based Testing Approach in Software Product Lines Using a Variability Language.
This paper presents the application of an automated testing approach for Software Product Lines (SPL) driven by its state-machine and variability models. Context: Model-based testing provides a technique for automatic generation of test cases using models. Introduction of a variability model in this technique can achieve testing automation in SPL. Method: We use UML and CVL (Common Variability Language) models as input, and JUnit test cases are derived from these models. This approach has been implemented using the UML2 Eclipse Modeling platform and the CVL-Tool. Validation: A model checking tool prototype has been developed and a case study has been performed. Conclusions: Preliminary experiments have proved that our approach can find structural errors in the SPL under test. In our future work we will introduce Object Constraint Language (OCL) constraints attached to the input UML mode
An architecture for a heterogeneous private IaaS management system
Cloud computing and, more particularly, private IaaS, is seen as a mature technology with a myriad solutions tochoose from. However, this disparity of solutions and products has instilled in potential adopters the fear of vendor and data lock-in. Several competing and incompatible interfaces and management styles have given even more voice to these fears. On top of this, cloud users might want to work with several solutions at the same time, an integration that is difficult to achieve in practice. In this paper, we propose a management architecture that tries to tackle these problems; it offers a common way of managing several cloud solutions, and an interface that can be tailored to the needs of the user. This management architecture is designed in a modular way, and using a generic information model. We have validated our approach through the implementation of the components needed for this architecture to support a sample private IaaS solution: OpenStac
Trust and distrust in relation to food risks in Spain: An approach to the socio-cultural representations of pregnant and breastfeeding women through the technique of free listing
In this paper, we explore the socio-cultural representations of trust and distrust in relation to food risks among pregnant and breastfeeding women. We have conducted a study based on an analysis of cultural domains in order to understand how mothers incorporate different social meanings and explore the most important categories they use when talking about trust/distrust in relation to food. We use the technique of free listings to analyse the main shared items or elements regarding trust and distrust in food among these mothers. Through an analysis of cultural domains that refers to concepts and themes related to trust and distrust of foods that are important to these women, and through the study of shared knowledge about these domains, we examine their socio-cultural representations related to health and diet of the 65 free listings on trust and the 64 on distrust collected from mothers. The pregnant and breastfeeding women who participated in the free listings cite foods they trust or distrust based on the specific properties they perceive them to have or other characteristics related to their origin, their handling, processing and distribution. Additionally, trust/distrust often depends on the qualities they attribute to the product. This paper shows aspects of the socio-cultural representations of food risks in periods in the life cycle of women -pregnancy and breastfeeding-characterized by a risk discourse where the precautionary principle is frequently used to manage uncertainty. These results might help the development of public health campaigns as well as adapting the messages of the health authorities to the general population
A federated repository for PaaS components in a multi-cloud environment
Cloud computing has seen an impressive growth in recent years, with virtualization technologies being massively adopted to create IaaS (Infrastructure as a Service) public and private solutions. Today, the interest is shifting towards the PaaS (Platform as a Service) model, which allows developers to abstract from the execution platform and focus only on the functionality. There are several public PaaS offerings available, but currently no private PaaS solution is ready for production environments. To fill this gap a new solution must be developed. In this paper we present a key element for enabling this model: a cloud repository based on the OSGi component model. The repository stores, manages, provisions and resolves the dependencies of PaaS software components and services. This repository can federate with other repositories located in the same or different clouds, both private and public. This way, dependencies can be fulfilled collaboratively, and new business models can be implemented
A Model-based Repository for Open Source Service and Component Integration.
Open source is a software development paradigm that has seen a huge rise in recent years. It reduces IT costs and time to market, while increasing security and reliability. However, the difficulty in integrating developments from different communities and stakeholders prevents this model from reaching its full potential. This is mainly due to the challenge of determining and locating the correct dependencies for a given software artifact. To solve this problem we propose the development of an extensible software component repository based upon models. This repository should be capable of solving the dependencies between several components and work with already existing repositories to access the needed artifacts transparently. This repository will also be easily expandable, enabling the creation of modules that support new kinds of dependencies or other existing repository technologies. The proposed solution will work with OSGi components and use OSGi itself
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