963 resultados para Avian Survey Techniques
Resumo:
The Internet has become a universal communication network tool. It has evolved from a platform that supports best-effort traffic to one that now carries different traffic types including those involving continuous media with quality of service (QoS) requirements. As more services are delivered over the Internet, we face increasing risk to their availability given that malicious attacks on those Internet services continue to increase. Several networks have witnessed denial of service (DoS) and distributed denial of service (DDoS) attacks over the past few years which have disrupted QoS of network services, thereby violating the Service Level Agreement (SLA) between the client and the Internet Service Provider (ISP). Hence DoS or DDoS attacks are major threats to network QoS. In this paper we survey techniques and solutions that have been deployed to thwart DoS and DDoS attacks and we evaluate them in terms of their impact on network QoS for Internet services. We also present vulnerabilities that can be exploited for QoS protocols and also affect QoS if exploited. In addition, we also highlight challenges that still need to be addressed to achieve end-to-end QoS with recently proposed DoS/DDoS solutions. © 2010 John Wiley & Sons, Ltd.
Resumo:
The community of Ferryland is located on the southeastern coast of the Avalon Peninsula. The town traditionally relied on a fishing-based economy until the collapse of the fishery in the early 1990s. The present economy emphasizes sustainable development in the tourism sector with focus on archaeology, geotourism and other recreational uses. This paper discusses coastal erosion and impacts on sites and infrastructure using methods including: local knowledge, Real Time Kinematic (RTK) surveying and other survey techniques, seawater level measurement, meteorological data from a locally-installed station, custom-made drifter tube buoys, photography, HD video, and investigation using various modes of transport including inflatable boat. The major findings of the study include that the residents and stakeholders are genuinely interested in and knowledgeable of coastal erosion. The causes of coastal erosion include: large waves, surge, longshore currents, harbour oscillations, mass wasting, and location of infrastructure causing alterations of these processes. Freeze-thaw Cycles (FTC), rainfall, and gravity loosen and transport rock, till, and fill materials downslope. Large waves and currents transport the materials alongshore or into the nearshore. Harbour oscillations causing high velocity currents (> 2 m/s) are responsible for shoreline erosion and damage to property in The Pool. Historical resources such as gun batteries and ordnance pieces which date to the 1700s are being lost or threatened through coastal erosion of till and rock cliffs. Improper drainage and maintenance is responsible for erosion of roads and supporting shoulders, necessitating mitigation measures. Sediment transport and deposition during and after large wave and surge events lead to undercutting of infrastructure and increased risk of washover of existing infrastructure. Erosion is ongoing at Bois Island and Ferryland Head Isthmus through slope processes and undercutting; The Pool and the lower Colony of Avalon site through harbour oscillations and related undermining; the tombolo and the main breakwater through wave attack; and Meade’s Cove including the East Coast Trail through wave attack and undercutting. The floor of the latrine in the lower Colony of Avalon site indicates that sea level was approximately 1.25m below present in the 1620s, a relative sea level rise rate of 3.2 mm/y. The recommendations include suggested mitigation to reduce impacts specific to each site.
Resumo:
Surveying habitats critical to the survival of grey nurse sharks in South-East Queensland has mapped critical habitats, gathered species inventories and developed protocols for ecological monitoring of critical habitats in southern Queensland. This information has assisted stakeholders with habitat definition and effective management. In 2002 members of UniDive applied successfully for World Wide Fund for Nature, Threatened Species Network funds to map the critical Grey Nurse Shark Habitats in south east Queensland. UniDive members used the funding to survey, from the boats of local dive operators, Wolf Rock at Double Island Point, Gotham, Cherub's Cave, Henderson's Rock and China Wall at North Moreton and Flat Rock at Point Look Out during 2002 and 2003. These sites are situated along the south east Queensland coast and are known to be key Grey Nurse Shark aggregation sites. During the project UniDive members were trained in mapping and survey techniques that include identification of fish, invertebrates and substrate types. Training was conducted by experts from the University of Queensland (Centre of Marine Studies, Biophysical Remote Sensing) and the Queensland Parks and Wildlife Service who are also UniDive members. The monitoring methods (see methods) are based upon results of the UniDive Coastcare project from 2002, the international established Reef Check program and research conducted by Biophysical Remote Sensing and the Centre of Marine Studies. Habitats were mapped using a combination of towed GPS photo transects, aerial photography, bathymetry surveys and expert knowledge. This data provides georeferenced information regarding the major features of each of Sites mapped including Wolf Rock
Resumo:
En la civilización de la antigua Roma, tres de los aspectos más importantes de la vida cotidiana estaban vinculados a la arquitectura: las termas, los acueductos y las tumbas. Esta investigación propone el estudio de la integración de sistemas avanzados para la documentación, gestión y valorización del patrimonio arquitectónico funerario de la Vie Latina y la Appia Antica, en estrecha relación con el tema del Paisaje Cultural. De hecho, el Parque de las Tumbas Latinas alberga uno de los complejos funerarios más importantes, que en la actualidad conserva el aspecto tradicional del antiguo paisaje romano. A lo largo de una vía empedrada, como todas las vías consulares, la Vía Latina (al igual que la Vía Appia Antica), que, como recordaba Tito Livio, conectaba en su día las ciudades de Roma con Capua, sigue manteniendo "congelado" el antiguo trazado urbano/paisajístico. El sistema multiforme del Ager Romanus y del sitio cultural Via Latina/Appia Antica estudiado en esta investigación es, por tanto, comparable a una estructura viva y dinámica y, como tal, debe ser analizada. Por lo tanto, para diseñar una herramienta de protección y gestión tan "potente" y adecuada para un sitio histórico de enorme importancia, fue necesario utilizar las técnicas de levantamiento arquitectónico más avanzadas que se utilizan actualmente (como el escaneo láser y la fotogrametría, junto con un software de análisis específico), acompañadas de un estudio en profundidad de las técnicas de construcción antiguas. El último aspecto clave que pretende abordar la investigación es la catalogación. De hecho, los sitios y monumentos históricos no se pueden mantener sólo mediante su uso y utilización pasiva, sino activando todas las operaciones de protección y conservación mediante intervenciones directas (mantenimiento/restauración) e indirectas, como la catalogación constante de las obras históricas y la consiguiente "catalogación dinámica".
Resumo:
As part of an epidemiological study of infectious bronchitis virus (IBV) in Brazil, 252 samples from IBV-suspect flocks were tested and the IBV-positive samples were analysed by sequencing of hypervariable regions 1 and 2 of the S1 gene. A high prevalence of IBV variants was found and the sequence analysis of 41 samples revealed a high molecular similarity among the Brazilian isolates (from 90.2 to 100% and from 85.3 to 100% nucleotide and amino acid identity, respectively). The Brazilian isolates showed low genetic relationship with Massachusetts (63.4 to 70.7%), European (45.9 to 75.6%), American (49.3 to 76.4%) and other reference serotypes (67.5 to 78.8%). The Brazilian isolates branched into one unique cluster, separate from the reference serotypes used for infectious bronchitis control in other countries. The variants analysed in this work had a high similarity with all previously published Brazilian IBV isolates, suggesting the presence and high prevalence of a unique or predominant genotype circulating in Brazil. In addition, the virus neutralization test showed that the three Brazilian isolates analysed in the present study are antigenically related to one another but are different from the Massachusetts serotype. The present study shows that IBVs of a unique genotype can be associated with different clinical diseases, and that low genetic variation was detected in this genotype over a long period of time. The molecular characterization of the Brazilian variants isolated from 2003 to 2009 from different geographic regions of the country shows that only one predominant genotype is widespread in the Brazilian territory, denominated in this study as BR-I genotype.
Resumo:
When exploring a virtual environment, realism depends mainly on two factors: realistic images and real-time feedback (motions, behaviour etc.). In this context, photo realism and physical validity of computer generated images required by emerging applications, such as advanced e-commerce, still impose major challenges in the area of rendering research whereas the complexity of lighting phenomena further requires powerful and predictable computing if time constraints must be attained. In this technical report we address the state-of-the-art on rendering, trying to put the focus on approaches, techniques and technologies that might enable real-time interactive web-based clientserver rendering systems. The focus is on the end-systems and not the networking technologies used to interconnect client(s) and server(s).
A Survey on Detection Techniques to Prevent Cross-Site Scripting Attacks on Current Web Applications
Resumo:
Social network has gained remarkable attention in the last decade. Accessing social network sites such as Twitter, Facebook LinkedIn and Google+ through the internet and the web 2.0 technologies has become more affordable. People are becoming more interested in and relying on social network for information, news and opinion of other users on diverse subject matters. The heavy reliance on social network sites causes them to generate massive data characterised by three computational issues namely; size, noise and dynamism. These issues often make social network data very complex to analyse manually, resulting in the pertinent use of computational means of analysing them. Data mining provides a wide range of techniques for detecting useful knowledge from massive datasets like trends, patterns and rules [44]. Data mining techniques are used for information retrieval, statistical modelling and machine learning. These techniques employ data pre-processing, data analysis, and data interpretation processes in the course of data analysis. This survey discusses different data mining techniques used in mining diverse aspects of the social network over decades going from the historical techniques to the up-to-date models, including our novel technique named TRCM. All the techniques covered in this survey are listed in the Table.1 including the tools employed as well as names of their authors.
Resumo:
Image-based Relighting (IBRL) has recently attracted a lot of research interest for its ability to relight real objects or scenes, from novel illuminations captured in natural/synthetic environments. Complex lighting effects such as subsurface scattering, interreflection, shadowing, mesostructural self-occlusion, refraction and other relevant phenomena can be generated using IBRL. The main advantage of image-based graphics is that the rendering time is independent of scene complexity as the rendering is actually a process of manipulating image pixels, instead of simulating light transport. The goal of this paper is to provide a complete and systematic overview of the research in Imagebased Relighting. We observe that essentially all IBRL techniques can be broadly classified into three categories (Fig. 9), based on how the scene/illumination information is captured: Reflectance function-based, Basis function-based and Plenoptic function-based. We discuss the characteristics of each of these categories and their representative methods. We also discuss about the sampling density and types of light source(s), relevant issues of IBRL.
Resumo:
National Highway Traffic Safety Administration, Washington, D.C.
Resumo:
"BNWL-WIND-9. UC-60."