193 research outputs found
Control of H2S emissions using an ozone oxidation process: Preliminary results
The problem of eliminating industrial emission odors does not have a simple solution, and consequently has not been researched extensively. Therefore, an experimental research program regarding oxidation of H2S through ozone was undertaken to verify the applicable limits of the procedure and, in addition, was designed to supply a useful analytical means of rationalizing the design of reactors employed in the sector
Model view management with triple graph transformation systems
The final publication is available at Springer via http://dx.doi.org/10.1007/11841883_25Proceedings of Third International Conference, ICGT 2006 Natal, Rio Grande do Norte, Brazil, September 17-23, 2006In this paper, we present our approach for model view management in the context of Multi-View Visual Languages (MVVLs). These are made of a number of diagram types (or viewpoints) that can be used for the specification of the different aspects of a system. Therefore, the user can build different system views conform to the viewpoints, which are merged in a repository in order to perform consistency checking. In addition, the user can define derived views by means of graph query patterns in order to extract information from a base model (a system view or the repository). We have provided automatic mechanisms to keep synchronized the base model and the derived view when the former changes. Predefined queries by the MVVL designer result in so-called audience-oriented views. Finally, semantic views are used for analysing the system by its translation into a semantic domain.
Our approach is based on meta-modelling to describe the syntax of the MVVL and each viewpoint, and on triple graph transformation systems to synchronize and maintain correspondences between the system views and the repository, as well as between the derived, audience-oriented and semantic views and the base models. We illustrate these concepts by means of an example in the domain of security for web systems.This work has been sponsored by the Spanish Ministry of Science and Education, projects TSI2005-08225-C07-06 and TSI2004-03394
The differential impact of relational health on alcohol consumption and consequences in first year college women
The Relational Health Indices (RHI) is a relatively new measure that assesses the strength of relationships. It has been found that relational health has a protective factor for women, such that it enhances positive experiences and limits negative ones. The current study is the first to use the RHI to examine the effect of relational health on alcohol consumption and alcohol consequences. First year college women were given questionnaires assessing relational health, drinking motives, and alcohol use in their first few months at a mid-sized, private university. Due to the social nature of college settings, it was predicted that relational health would moderate the relationship between motives and alcohol consumption. Further, due to the protective factor of relational health, it was predicted that relational health would attenuate the relationship between drinking and negative consequences. These hypotheses were supported. Relational health, moderated the relationship between both social and coping drinking motives and drinking, such that women with strong relational health towards their peers and community who also had high social and coping motives, drank more than those with weaker relationships. Paradoxically, relational health also moderated the relationship between drinking and consequences such that heavy drinking women with strong relational health experienced fewer negative consequences than women with weaker relational health. Results indicate that although relational health is associated with an increase in alcohol consumption, it may also serve as a protective factor for alcohol-related negative consequences. Future research and interventions may seek to de-link the relational health-drinking connection in the college student environment
Dynamic Role-Based Access Control for Decentralized Applications
Access control management is an integral part of maintaining the security of
an application. Although there has been significant work in the field of cloud
access control mechanisms, however, with the advent of Distributed Ledger
Technology (DLT), on-chain access control management frameworks hardly exist.
Existing access control management mechanisms are tightly coupled with the
business logic, resulting in governance issues, non-coherent with existing
Identity Management Solutions, low security, and compromised usability. We
propose a novel framework to implement dynamic role-based access control for
decentralized applications (dApps). The framework allows for managing access
control on a dApp, which is completely decoupled from the business application
and integrates seamlessly with any dApps. The smart contract architecture
allows for the independent management of business logic and execution of access
control policies. It also facilitates secure, low cost, and a high degree of
flexibility of access control management. The proposed framework promotes
decentralized governance of access control policies and efficient smart
contract upgrades. We also provide quantitative and qualitative metrics for the
efficacy and efficiency of the framework. Any Turing complete smart contract
programming language is an excellent fit to implement the framework. We expect
this framework to benefit enterprise and non-enterprise dApps and provide
greater access control flexibility and effective integration with traditional
and state of the art identity management solutions.Comment: 6 pages, 3 figures, 1 tabl
Comprehensive Life Cycle Support for Access Rules in Information Systems: The CEOSIS Project
The definition and management of access rules (e.g., to control access to business documents and business functions) is a fundamental task in any enterprise
information system (EIS). While there exists considerable work on how to specify and represent access rules, only little research has been spent on access rule changes. Examples include the evolution of organizational models with need for subsequent adaptation of related access rules as well as direct access rule modifications (e.g., to state a previously defined rule more precisely). This paper
presents a comprehensive change framework for the controlled evolution of role-based access rules in EIS. First, we consider changes of organizational models and elaborate how they affect existing access rules. Second, we define change operations which enable direct adaptations of access rules. In the latter context, we define the formal semantics of access rule changes based on operator
trees. Particularly, this enables their unambiguous application; i.e., we can precisely determine which effects are caused by respective rule changes. This is
important, for example, to be able to efficiently and correctly adapt user worklists in process-aware information systems. Altogether this paper contributes to comprehensive life cycle support for access rules in (adaptive) EIS
The iTEC Technical Artefacts, Architecture and Educational Cloud
This chapter introduces the technical artefacts of the iTEC project in
the context of a cloud architecture. The rationale for the technology developed
in the iTEC project follows from its overall aim to re-engineer the uptake of ICT
in schools. To that end, iTEC focused (a) on some important barriers for the uptake
of ICT such the effort that teachers must make in redesigning their teaching and
fi nding the right resources for that, and (b) on enablers for the uptake of ICT, such
as providing engaging experiences both for the learner and teacher. The technical
innovations are centred around three themes: innovations in the support of learning
design, innovations by using a-typical resources, and innovations in the integration
and management of learning services and resources. Next this chapter presents the
cloud architecture adopted by all technology providers, including a shared user
management and control system, the shared data models and interoperability solutions.
The technical artefacts and then further elaborated in the ensuing chapters
Relaxin-1–deficient mice develop an age-related progression of renal fibrosis
Relaxin-1–deficient mice develop an age-related progression of renal fibrosis.BackgroundRelaxin (RLX) is a peptide hormone that stimulates the breakdown of collagen in preparation for parturition and when administered to various models of induced fibrosis. However, its significance in the aging kidney is yet to be established. In this study, we compared structural and functional changes in the kidney of aging relaxin-1 (RLX-/-) deficient mice and normal (RLX+/+) mice.MethodsThe kidney cortex and medulla of male and female RLX+/+ and RLX-/- mice at various ages were analyzed for collagen content, concentration, and types. Histologic analysis, reverse transcription-polymerase chain reaction (RT-PCR) of relaxin and relaxin receptor mRNA expression, receptor autoradiography, glomerular isolation/analysis, and serum/urine analysis were also employed. Relaxin treatment of RLX-/- mice was used to confirm the antifibrotic effects of the peptide.ResultsWe demonstrate an age-related progression of renal fibrosis in male, but not female, RLX-/- mice with significantly (P < 0.05) increased tissue dry weight, collagen (type I) content and concentration. The increased collagen expression in the kidney was associated with increased glomerular matrix and to a lesser extent, interstitial fibrosis in RLX-/- mice, which also had significantly increased serum creatinine (P < 0.05) and urinary protein (P < 0.05). Treatment of RLX-/- mice with relaxin in established stages of renal fibrosis resulted in the reversal of collagen deposition.ConclusionThis study supports the concept that relaxin may provide a means to regulate excessive collagen deposition during kidney development and in diseased states characterized by renal fibrosis
Fog computing security: a review of current applications and security solutions
Fog computing is a new paradigm that extends the Cloud platform model by providing computing resources on the edges of a network. It can be described as a cloud-like platform having similar data, computation, storage and application services, but is fundamentally different in that it is decentralized. In addition, Fog systems are capable of processing large amounts of data locally, operate on-premise, are fully portable, and can be installed on heterogeneous hardware. These features make the Fog platform highly suitable for time and location-sensitive applications. For example, Internet of Things (IoT) devices are required to quickly process a large amount of data. This wide range of functionality driven applications intensifies many security issues regarding data, virtualization, segregation, network, malware and monitoring. This paper surveys existing literature on Fog computing applications to identify common security gaps. Similar technologies like Edge computing, Cloudlets and Micro-data centres have also been included to provide a holistic review process. The majority of Fog applications are motivated by the desire for functionality and end-user requirements, while the security aspects are often ignored or considered as an afterthought. This paper also determines the impact of those security issues and possible solutions, providing future security-relevant directions to those responsible for designing, developing, and maintaining Fog systems
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