934 resultados para distributed denial-of-service attack


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Rapid prototyping environments can speed up the research of visual control algorithms. We have designed and implemented a software framework for fast prototyping of visual control algorithms for Micro Aerial Vehicles (MAV). We have applied a combination of a proxy-based network communication architecture and a custom Application Programming Interface. This allows multiple experimental configurations, like drone swarms or distributed processing of a drone's video stream. Currently, the framework supports a low-cost MAV: the Parrot AR.Drone. Real tests have been performed on this platform and the results show comparatively low figures of the extra communication delay introduced by the framework, while adding new functionalities and flexibility to the selected drone. This implementation is open-source and can be downloaded from www.vision4uav.com/?q=VC4MAV-FW

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Electronic services are a leitmotif in ‘hot’ topics like Software as a Service, Service Oriented Architecture (SOA), Service oriented Computing, Cloud Computing, application markets and smart devices. We propose to consider these in what has been termed the Service Ecosystem (SES). The SES encompasses all levels of electronic services and their interaction, with human consumption and initiation on its periphery in much the same way the ‘Web’ describes a plethora of technologies that eventuate to connect information and expose it to humans. Presently, the SES is heterogeneous, fragmented and confined to semi-closed systems. A key issue hampering the emergence of an integrated SES is Service Discovery (SD). A SES will be dynamic with areas of structured and unstructured information within which service providers and ‘lay’ human consumers interact; until now the two are disjointed, e.g., SOA-enabled organisations, industries and domains are choreographed by domain experts or ‘hard-wired’ to smart device application markets and web applications. In a SES, services are accessible, comparable and exchangeable to human consumers closing the gap to the providers. This requires a new SD with which humans can discover services transparently and effectively without special knowledge or training. We propose two modes of discovery, directed search following an agenda and explorative search, which speculatively expands knowledge of an area of interest by means of categories. Inspired by conceptual space theory from cognitive science, we propose to implement the modes of discovery using concepts to map a lay consumer’s service need to terminologically sophisticated descriptions of services. To this end, we reframe SD as an information retrieval task on the information attached to services, such as, descriptions, reviews, documentation and web sites - the Service Information Shadow. The Semantic Space model transforms the shadow's unstructured semantic information into a geometric, concept-like representation. We introduce an improved and extended Semantic Space including categorization calling it the Semantic Service Discovery model. We evaluate our model with a highly relevant, service related corpus simulating a Service Information Shadow including manually constructed complex service agendas, as well as manual groupings of services. We compare our model against state-of-the-art information retrieval systems and clustering algorithms. By means of an extensive series of empirical evaluations, we establish optimal parameter settings for the semantic space model. The evaluations demonstrate the model’s effectiveness for SD in terms of retrieval precision over state-of-the-art information retrieval models (directed search) and the meaningful, automatic categorization of service related information, which shows potential to form the basis of a useful, cognitively motivated map of the SES for exploratory search.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Network RTK (Real-Time Kinematic) is a technology that is based on GPS (Global Positioning System) or more generally on GNSS (Global Navigation Satellite System) observations to achieve centimeter-level accuracy positioning in real time. It is enabled by a network of Continuously Operating Reference Stations (CORS). CORS placement is an important problem in the design of network RTK as it directly affects not only the installation and running costs of the network RTK, but also the Quality of Service (QoS) provided by the network RTK. In our preliminary research on the CORS placement, we proposed a polynomial heuristic algorithm for a so-called location-based CORS placement problem. From a computational point of view, the location-based CORS placement is a largescale combinatorial optimization problem. Thus, although the heuristic algorithm is efficient in computation time it may not be able to find an optimal or near optimal solution. Aiming at improving the quality of solutions, this paper proposes a repairing genetic algorithm (RGA) for the location-based CORS placement problem. The RGA has been implemented and compared to the heuristic algorithm by experiments. Experimental results have shown that the RGA produces better quality of solutions than the heuristic algorithm.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article is based on an analysis of narratives of 26 offenders with mental health problems living in the United Kingdom. It explores the impact of an ascribed dangerous status and the construction of the self as moral and responsible in response to this label with reference to the literature on denial, deviance disavowal and other “techniques of neutralization” and Goffman's presentation of self. Two dominant strands are identified in relation to the construction of moral self-hood: “Not my fault” and “Good at heart” narratives. “Techniques of neutralization” are widely drawn on, particularly denial of responsibility in the “Not my fault” narratives that seek to explain anti-social behavior with reference to external forces such as a hostile environment inhibiting their ability to control their lives. In contrast, “Good at heart” narratives draw on the essentially good and moral nature of the inner-self. Both are used as evidence of sharing and adhering to moral norms in order to present an acceptable and credible self.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A prominent research focus, especially in the context of EU public funding, has been the systematic use of the Internet for new ways of value creation in the services sector. This idea of service networks in the Internet, frequently dubbed the Internet of Services or Web service ecosystems, wants to make services tradable in digital media. In order to enable communication and trade between providers and consumers of services, the Internet of Services requires a standard that creates a "commercial envelope" around a service. This is where the Unified Service Description Language (USDL) comes into play as a normative and balanced unification of service information. The unified description established by USDL is machine-processable, considers technical and business aspects of a service as well as functional and non-functional attributes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Enabling web-based service networks and ecosystems requires a way of describing services by a "commercial envelope" as discussed in Chapter 1. A uniform conception of services across all walks of life (including technical services) is required capturing business, operational and technical aspects. Therefore, our proposed Unified Service Description Language (USDL) particularly draws from and generalizes the best-of-breed approaches presented in Part I. The following chapter presents the design rationale of USDL where the different aspects are put in a framework of descriptions requirements. This is followed by the subsequent chapters of this part that provide details on specific aspects such as pricing or legal issues.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The ubiquity of multimodality in hypermedia environments is undeniable. Bezemer and Kress (2008) have argued that writing has been displaced by image as the central mode for representation. Given the current technical affordances of digital technology and user-friendly interfaces that enable the ease of multimodal design, the conspicuous absence of images in certain domains of cyberspace is deserving of critical analysis. In this presentation, I examine the politics of discourses implicit within hypertextual spaces, drawing textual examples from a higher education website. I critically examine the role of writing and other modes of production used in what Fairclough (1993) refers to as discourses of marketisation in higher education, tracing four pervasive discourses of teaching and learning in the current economy: i) materialization, ii) personalization, iii) technologisation, and iv) commodification (Fairclough, 1999). Each of these arguments is supported by the critical analysis of multimodal texts. The first is a podcast highlighting the new architectonic features of a university learning space. The second is a podcast and transcript of a university Open Day interview with prospective students. The third is a time-lapse video showing the construction of a new science and engineering precinct. These three multimodal texts contrast a final web-based text that exhibits a predominance of writing and the powerful absence or silencing of the image. I connect the weightiness of words and the function of monomodality in the commodification of discourses, and its resistance to the multimodal affordances of web-based technologies, and how this is used to establish particular sets of subject positions and ideologies through which readers are constrained to occupy. Applying principles of critical language study by theorists that include Fairclough, Kress, Lemke, and others whose semiotic analysis of texts focuses on the connections between language, power, and ideology, I demonstrate how the denial of image and the privileging of written words in the multimodality of cyberspace is an ideological effect to accentuate the dominance of the institution.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Purpose – While there have been numerous studies on the antecedents and consequences of service quality, there has been little investigation of the moderators of service quality. The purpose of this study is to demonstrate the effects of two moderators: service convenience and the social servicescape. The moderating effects are tested in two service settings: retail and hedonic (concert). Design/methodology/approach – A survey of 270 customers at kitchen display showrooms and 320 concert-goers was undertaken. The results were analysed using regression analysis. Findings – The results show support for ten of the 12 hypotheses. Service convenience moderated the relationships between perceived service quality and its three sub-dimensions (interaction, environment, and outcome quality), differently in different settings (retail vs hedonic). This supports the authors' general argument that the outcome dimension tends to be more important to customers in a retail setting, while interaction and environment quality dimensions tend to be more important in hedonic service consumption. Practical implications – These findings suggest that managers need to use different service management tactics in retail and hedonic service settings. Specifically managers in retail settings need to pay more attention to service convenience to achieve service quality and managers in hedonic settings should concentrate on the social servicescape. Originality/value – This paper is the first to test the moderating factors of service convenience and social servicescape on service quality.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In recent years, de-regulation in the airline industry and the introduction of low-cost carriers have conspired to produce significant changes in the airport landscape. From an airport operator’s perspective, one of the most notable has been the shift of capital revenue from traditional airline sources (through exclusive use, long term lease arrangements) to passengers (by way of fees collected from ticket sales). As a result of these developments, passengers have become recognized as major stakeholders who have the power to influence airport profitability. This link between passenger satisfaction and profitability has generated industry wide interest in the “passenger experience”. In this paper, we define the factors which influence passenger experience, namely (a) artifacts, (b) services and (c) the terminal building, and explore the challenges that exist in the current approaches to terminal design. On the basis of these insights, we propose a conceptual model of passenger experience, and motivate its use as a framework for further research into improving terminal design from a passenger oriented perspective.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

TOD: - A fully planned, mixed use development equipped with good quality transit service and infrastructure for walking and cycling Hypothesis: -TOD will help to reduce urban transport congestion Method: -Comparison of a TOD with non TOD urban environments -Residents’ trip characteristics

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Deterministic transit capacity analysis applies to planning, design and operational management of urban transit systems. The Transit Capacity and Quality of Service Manual (1) and Vuchic (2, 3) enable transit performance to be quantified and assessed using transit capacity and productive capacity. This paper further defines important productive performance measures of an individual transit service and transit line. Transit work (p-km) captures the transit task performed over distance. Passenger transmission (p-km/h) captures the passenger task delivered by service at speed. Transit productiveness (p-km/h) captures transit work performed over time. These measures are useful to operators in understanding their services’ or systems’ capabilities and passenger quality of service. This paper accounts for variability in utilized demand by passengers along a line and high passenger load conditions where passenger pass-up delay occurs. A hypothetical case study of an individual bus service’s operation demonstrates the usefulness of passenger transmission in comparing existing and growth scenarios. A hypothetical case study of a bus line’s operation during a peak hour window demonstrates the theory’s usefulness in examining the contribution of individual services to line productive performance. Scenarios may be assessed using this theory to benchmark or compare lines and segments, conditions, or consider improvements.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Higher ambient temperatures will increase heat stress on workers, leading to impacts upon their individual health and productivity. In particular, research has indicated that higher ambient temperatures can increase the prevalence of urolithiasis. This thesis examines the relationship between ambient heat exposure and urolithiasis among outdoor workers in a shipbuilding company in Guangzhou, China, and makes recommendations for minimising the possible impacts of high ambient temperatures on urolithiasis. A retrospective 1:4 matched case-control study was performed to investigate the association between ambient heat exposure and urolithiasis. Ambient heat exposure was characterised by total exposure time, type of work, department and length of service. The data were obtained from the affiliated hospital of the shipbuilding company under study for the period 2003 to 2010. A conditional logistic regression model was used to estimate the association between heat exposure and urolithiasis. This study found that the odds ratio (OR) of urolithiasis for total exposure time was 1.5 (95% confidence interval (CI): 1.2–1.8). Eight types of work in the shipbuilding company were investigated, including welder, assembler, production security and quality inspector, planing machine operator, spray painter, gas-cutting worker and indoor employee. Five out of eight types of work had significantly higher risks for urolithiasis, and four of the five mainly consisted of outdoors work with ORs of 4.4 (95% CI: 1.7–11.4) for spray painter, 3.8 (95% CI: 1.9–7.2) for welder, 2.7 (95% CI: 1.4–5.0) for production security and quality inspector, and 2.2 (95% CI: 1.1–4.3) for assembler, compared to the reference group (indoor employee). Workers with abnormal blood pressure (hypertension) were more likely to have urolithiasis with an OR of 1.6 (95% CI: 1.0–2.5) compared to those without hypertension. This study contributes to the understanding of the association between ambient heat exposure and urolithiasis among outdoor workers in China. In the context of global climate change, this is particularly important because rising temperatures are expected to increase the prevalence of urolithiasis among outdoor workers, putting greater pressure on productivity, occupational health management and health care systems. The results of this study have clear implications for public health policy and planning, as they indicate that more attention is required to protect outdoor workers from heat-related urolithiasis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: The present study seeks to examine the impact of therapeutic interventions for people from refugee backgrounds within a naturalistic setting. Method: Sixty-two refugees from Burma were assessed soon after arriving in Australia. All participants received standard interventions provided by a resettlement organisation which included therapeutic interventions, assessment, social assistance, and referrals where appropriate. At the completion of service provision a follow-up assessment was conducted. Results: Over the course of the intervention, participants experienced a significant decrease in symptoms of post-traumatic stress disorder, anxiety, depression and somatisation. Pre-intervention symptoms predicted symptoms post-intervention for post-traumatic stress, anxiety, and somatisation. Post-migration living difficulties, the number of traumas experienced, and the number of contacts with the service agency were unrelated to all mental health outcomes. Conclusions: In the first Australian study of its kind, reductions in mental health symptoms post-intervention were significantly linked to pre-intervention symptomatology and the number of therapy sessions predicted post-intervention symptoms of post-traumatic stress. Future studies need to include larger samples and control groups to verify findings.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Currently in the Australian higher education sector higher productivity from allied health clinical education placements are a contested issue. This paper will report results of a study that investigated output changes associated with occupational therapy and nutrition/dietetics clinical education placements in Queensland, Australia. Supervisors’ and students’ time use during placements and how this changes for supervisors compared to when students are not present in the workplace is also presented. Methodology/Principal Findings: A cohort design was used with students from four Queensland universities, and their supervisors employed by Queensland Health. There was an increasing trend in the number of occasions of service delivered when the students were present, and a statistically significant increase in the daily mean length of occasions of service delivered during the placement compared to pre-placement levels. For project-based placements that were not directly involved in patient care, supervisors’ project activity time decreased during placements, with students undertaking considerably more time in project activities. Conclusions/Significance: A novel method for estimating productivity and time use changes during clinical education programs for allied health disciplines has been applied. During clinical education placements there was a net increase in outputs, suggesting supervisors engage in longer consultations with patients for the purpose of training students, while maintaining patient numbers. Other activities are reduced. This paper is the first time these data have been shown and form a good basis for future assessments of the economic impact of student placements for allied health disciplines.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Late discovery is a term used to describe the experience of discovering the truth of one’s genetic origins as an adult. Following discovery, late discoverers face a lack of recognition and acknowledgment of their concerns from family, friends, community and institutions. They experience pain, anger, loss, grief and frustration. This presentation shares the findings of the first qualitative study of both late discovery of adoptive and donor insemination offspring (heterosexual couple use only) experiences. It is also the first study of late discovery experiences undertaken from an ethical perspective. While this study recruited new participants, it also included an ethical re-analysis of existing late discovery accounts across both practices. The findings of this study (a) draws links between past adoption and current donor insemination (heterosexual couple only) practices, (b) reveals that late discoverers are demanding acknowledgment and recognition of the particularity of their experiences, and (c) offers insights into conceptual understandings of the ‘best interests of the child’ principle. These insights derive from the lived experiences of those whose biological and social worlds have been sundered and secrecy and denial of difference used to conceal this. It suggests that acknowledging the equal moral status of the child may be useful in strengthening conceptual understandings of the ‘best interests of the child’ principle. This equal moral status involves ensuring that personal autonomy and the ability to exercise free will is protected; that the integrity of the relationships of trust expected and demanded between parent/s and children is defended and supported; and that equal access to normative socio-cultural practices, that is; non-fictionalised birth certificates and open records, is guaranteed.