A two layers video coding scheme for ATM networks

In transmission of image sequences over ATM networks, the channel sharing efficiency in packet loss conditions is important. As one of possible approaches two-layer video coding methods have been proposed. These methods transmit video information over the network with different levels of protection with respect to packet loss. In this paper, a two-layer coding method using pyramid structure is proposed and several realizations of two-layer video coding methods are presented and their performances are compared.

Marine protected areas (MPAs) are important tools for the evaluation of the biodiversity and status of marine systems. However, not all MPAs are equal in their design and management; therefore, it is important to understand how different levels of protection affect the fish communities. In the present study, the shallow reef-area fishes of seven areas in Fernando de Noronha archipelago (north-eastern Brazil) with dissimilar habitat characteristics and different levels of environmental protection (no-take MPA and MPA) were compared. In total, 140 visual censuses were performed, in which 12 958 fishes of 27 families and 50 species were recorded. Differences were recorded between no-take MPAs and MPAs in the benthic composition, abiotic data and fish-community structure and composition. These differences were associated with a higher diversity, richness, density of larger fishes and top target fish families, and biomass per census (nearly 2-fold higher in the no-take MPA). Our findings suggested that the differences in the ichthyofauna were probably more related to the different levels of protection than to dissimilarities in the habitat structure among areas, and that the local no-take MPA (National Marine Park of Fernando de Noronha) is effective in maintaining the shallow reef-area fish communities healthy and diverse.

Statutes, regulations, and forest restoration represent measures aimed at promoting the conservation of threatened species. We analyzed the abundance of red-listed tree species within three conservation zones with differing levels of protection in the Ta Xua Nature Reserve in north-western Vietnam, a rarely studied region within a biodiversity hotspot. The study area included: (1) the undisturbed core zone; (2) the low intensity traditional forest use buffer zone; and (3) the forest restoration zone. Red-listed tree species richness (IUCN and Vietnamese Red Lists combined) amounted to 16 in the core zone, 10 in the buffer zone, and five in the restoration zone; a similar declining trend was found for all tree species at 193, 173 and 135 for each respective zone. Differences between zones were even more pronounced when species richness was predicted using the Chao2 estimator. Most red-listed species, such as Fujian Cypress ( Fokienia hodginsii), reached their highest densities in the core zone, but one species ( Quercus platycalyx) was quite abundant in the restoration zone. For some red-listed tree species, canonical correspondence analysis suggested relationships among the presence of footpaths, canopy closure and basal area, suggesting reduced abundance caused by human activities. Our data indicate that conservation effectiveness is related to the level of statutory protection afforded to a particular area, with full protection ensuring more robust conservation outcomes.

Partial protection disallowing trawling has conservation benefits in a subtropical marine park

Taking an environmental ethics perspective to understand what we should expect from EIA in terms of biodiversity protection

This paper describes a video scheme which is capable of compensating for the information losses due to packet loss. Packet losses in ATM (asynchronous transfer mode) networks have such a great impact on the design of coding algorithms and network architectures that they should be exhaustively discussed and resolved. One solution to this problem is the transmission of the video signal over the network with different levels of protection. The information which is considered sufficient to generating the minimum acceptable quality in a video signal is transmitted in a very protected way. On the contrary, other parts of the information necessary to increase the quality of the coded images up to the desired level are sent in a normal channel. In this paper a hierarchical approach is presented and its performances are compared with MPEG-2 system coding in the same circumstances.

Spatial variation of intertidal assemblages at Tavolara-Capo Coda Cavallo MPA (NE Sardinia): geographical vs. protection effect

‘The mesh method’ in lightning protection standards – Revisited

In Central Europe, protected areas are too small to ensure survival of populations of large carnivores. In the surrounding areas, these species are often persecuted due to competition with game hunters. Therefore, understanding how predation intensity varies spatio-temporally across areas with different levels of protection is fundamental. We investigated the predation patterns of Eurasian lynx (Lynx lynx) on roe deer (Capreolus capreolus) and red deer (Cervus elaphus) in both protected areas and multi-use landscapes of the Bohemian Forest Ecosystem. Based on 359 roe and red deer killed by 10 GPS-collared lynx, we calculated the species-specific annual kill rates and tested for effects of season and lynx age, sex and reproductive status. Because roe and red deer in the study area concentrate in unprotected lowlands during winter, we modeled spatial distribution of kills separately for summer and winter and calculated-the probability of a deer killed by lynx and-the expected number of kills for areas with different levels of protection. Significantly more roe deer (46.05–74.71/year/individual lynx) were killed than red deer (1.57–9.63/year/individual lynx), more deer were killed in winter than in summer, and lynx family groups had higher annual kill rates than adult male, single adult female and subadult female lynx. In winter the probability of a deer killed and the expected number of kills were higher outside the most protected part of the study area than inside; in summer, this probability did not differ between areas, and the expected number of kills was slightly larger inside than outside the most protected part of the study area. This indicates that the intensity of lynx predation in the unprotected part of the Bohemian Forest Ecosystem increases in winter, thus mitigation of conflicts in these areas should be included as a priority in the lynx conservation strategy.

The Dark Silicon provides opportunities to realize Reliability-Heterogeneous Processors with ISA compatible cores having different levels of protection against reliability threats (like soft errors). This paper presents design-time customization of Reliability-Heterogeneous Processors given a set of applications and area constraints. A run-time system adaptively manages the soft error resilience under a given thermal design power (TDP) budget. We synthesize an embedded processor with different levels of protection and present area and power results for a 45nm technology. We illustrate the benefits of adaptive soft error resilience by comparing it with four different state-of-the-art approaches where we achieve 58%-96% overall system reliability improvements under a tight TDP constraint (corresponding to a 65% dark area).

Commentators in the rest of Europe often have difficulty in understanding why the United Kingdom has a very liberal regulation of embryo research and often misinterpret it as based on the view that embryos are not morally important. This chapter attempts to explain how the UK reached its present regulatory position, and what it implies about the status of the embryo. In the United Kingdom somatic cell nuclear transfer (SCNT) for research, and potentially in the future therapeutic purposes, is legally permitted if it falls within the purposes specified in Schedule 3 of the Human Fertilization and Embryology (HFE) Act 1990 as amended in the HFE (Research Purposes) Regulations of January 2001. After the demonstration in 1998 of the possibilities for the derivation of human embryonic stem cell lines and of reproductive cloning in mammals it became clear that the derivation of stem cell lines was not an allowable purpose under the HFE Act.

One of the most important pieces of three-dimensional (3-D) video transmission over wireless channels is the design of error-resilient video transmission. Naturally, many techniques used in two-dimensional (2-D) can be adapted or extended to exploit 3-D video properties. One of those techniques is unequal error protection (UEP) where different parts of 3-D video are protected with different levels of protection. Exploiting the characteristics of 3-D video to provide UEP schemes is not fully investigated. In this chapter, an UEP scheme based on hierarchical quadrature amplitude modulation (HQAM) for 3-D video transmission is proposed. The proposed scheme exploits the unique characteristics of the color plus depth map stereoscopic video where the color sequence has a significant impact on the reconstructed video quality. The UEP scheme assigned more protection to the color sequence than the depth map sequence in order to achieve high quality 3-D video. However, the different levels of protection are assigned through 16-quadrature amplitude modulation (16-QAM). The color data with high priority (HP) are mapped onto the most significant bits (MSBs) of QAM constellation points and depth map with low priority (LP) is mapped onto the less significant bits (LSBs). Simulation results show that the proposed UEP scheme outperforms the classical equal error protection (EEP) by up to 5 dB gain in terms of the received left and right views quality.

The trend in the development of intelligent optical networks is the move towards a unified solution, to support voice, data, and various services. Nowadays, different applications may need different levels of protection and differ in how much they are willing to pay for the service they get. A control scheme which is used to set up and tear down lightpaths, should not only be fast and efficient, but also be scalable. In addition, it should also try to minimize the connection cost and the number of blocked connections while satisfying the requested level of availability. In this work we choose the availability of a connection as a quality of service (QoS) parameter to denote different levels of protection. It is proven that the Availability-Guaranteed least-cost (AGLC) routing problem is NP-complete. We propose a distributed control scheme based on parallel fixed alternative routing approach for establishing AGLC lightpaths. The proposed framework performance is studied through extensive simulation experiments on wavelength selective network with different traffic loads. The simulation results show that our proposed framework provides better performance in terms of average blocking probability, and average routing distance average path cost.

At present the design of the Lightning protection systems (LPS) for structures as stipulated in standards is based on the electro - geometrical method, which was initially used to protect power lines from lightning. A derivative of the electro-geometrical method is the rolling sphere method. This method together, with the protection angle method and mesh method are used almost in all lightning standards as the measure in installing the lightning protection systems of grounded structures. In the mesh method, the dimension of the cell size in different levels of protection is determined using the rolling sphere method. Since the rolling sphere method does not take into account the physics of the lightning attachment process there is a need to evaluate the validity of the stipulated value in standards of the minimum lightning current that can penetrate through the mesh in different levels of protection. In this paper, meshes of different sizes as stipulated in the lightning protection standards were tested for their ability to intercept lightning flashes using a lightning attachment model that takes into account the physics of connecting leaders on. The results are in reasonable agreement with the specifications given in the lightning protection standards.

This work considers two important aspects of modern communication networks, network survivability, and energy efficiency. Survivability is a design requirement to provide failure recovery against network outages such as fiber cuts. To ensure survivability, traditionally, spare network (i.e., backup) resources are reserved in case of failures of primary (i.e., working) network resources. On the other hand, energy efficiency is required to cope with the continuous growth of the Internet traffic. Backup resources increase the energy consumption, especially if constantly powered-on. Hence, a trade-off between energy efficiency and network resiliency arises. To increase transport capacity and reduce energy consumption, wavelength division multiplexed (WDM) networks are adopted as the most practical solution for data transport in core networks, which are the focus of our work. In WDM networks, different levels of protection (i.e., dedicated, shared) can be implemented for different traffic demands, and different protection levels are characterized by different power consumptions. We consider a differentiated quality of protection (Diff-QoP) scheme where different levels of protection are provided. In this context, we investigate on two different power-reduction strategies to be used in protected WDM networks: (i) setting backup devices into low-power modes (sleep mode) and (ii) adapting the devices (i.e., transmitting/receiving equipment) usage to hourly traffic variations. We present exact modeling through Integer Linear Program (ILP) of the three scenarios and a provisioning algorithm to solve the problem of power minimized design of resilient optical core networks, under static and dynamic traffic conditions. We evaluate the performance of the proposed algorithm under static traffic conditions by comparing the obtained results with the optimal solution, in absence of traffic grooming. We show that the proposed heuristic reduces the computational time by three orders of magnitude with an optimality gap ranging from 8.88 up to 23.88%. Furthermore, we include traffic grooming and solve the problem under dynamic traffic conditions. Our findings show that enabling sleep mode (SM) for backup devices can help reduce total power consumption up to 20 and up to 38% when considering with Diff-QoP. Finally, adapting the number of transmitting/receiving devices to actual traffic needs guarantees power savings up to 80%, especially during off-peak hours.