Performance evaluation of mobile agent based resource management protocol for MANETs

The nodes with dynamicity, and management without administrator are key features of mobile ad hoc networks (1VIANETs). Increasing resource requirements of nodes running different applications, scarcity of resources, and node mobility in MANETs are the important issues to be considered in allocation of resources. Moreover, management of limited resources for optimal allocation is a crucial task. In our proposed work we discuss a design of resource allocation protocol and its performance evaluation. The proposed protocol uses both static and mobile agents. The protocol does the distribution and parallelization of message propagation (mobile agent with information) in an efficient way to achieve scalability and speed up message delivery to the nodes in the sectors of the zones of a MANET. The protocol functionality has been simulated using Java Agent Development Environment (JADE) Framework for agent generation, migration and communication. A mobile agent migrates from central resource rich node with message and navigate autonomously in the zone of network until the boundary node. With the performance evaluation, it has been concluded that the proposed protocol consumes much less time to allocate the required resources to the nodes under requirement, utilize less network resources and increase the network scalability. (C) 2015 Elsevier B.V. All rights reserved.

Tax-Based Fisheries Management: The Case Study Of The Cantabrian Anchovy Fishery

A dynamic optimisation framework is adopted to show how tax-based management systems theoretically correct the inefficient allocation of fishing resources derived from the stock externality. Optimal Pigouvian taxes on output (τ) and on inputs (γ) are calculated, compared and considered as potential alternatives to the current regulation of VIII division Cantabrian anchovy fishery. The sensibility analysis of optimal taxes illustrates an asymmetry between (τ) and (γ) when cost price ratio varies. The distributional effects also differ. Special attention will be paid to the real implementation of the tax-based systems in fisheries.

Prey preference of lingcod (Ophiodon elongatus), a top marine predator: implications for ecosystem-based fisheries management

Many highly exploited ecosystems are managed on the basis of single-species demographic information. This management approach can exacerbate tensions among stakeholders with competing interests who in turn rely on data with notoriously high variance. In this case study, an application of diet and dive survey data was used to describe the prey preference of lingcod (Ophiodon elongatus) in a predictive framework on nearshore reefs off Oregon. The lingcod is a large, fast-growing generalist predator of invertebrates and fishes. In response to concerns that lingcod may significantly reduce diminished populations of rockfishes (Sebastes spp.), the diets of 375 lingcod on nearshore reefs along the Oregon Coast were compared with estimates of relative prey availability from dive surveys. In contrast to the transient pelagic fishes that comprised 46% of lingcod diet by number, rockfishes comprised at most 4.7% of prey items. Rockfishes were the most abundant potential prey observed in dive surveys, yet they were the least preferred. Ecosystem-based fisheries management (EBFM) requires information about primary trophic relationships, as well as relative abundance and distribution data for multiple species. This study shows that, at a minimum, predation relative to prey availability must be considered before predator effects can be understood in a management context.

Community-based aquaculture in India: strengths, weaknesses, opportunities and threats

Community-based aquaculture founded on the principles of common interest groups working together regardless of sex and age has been an effective tool for implementing scientific aquaculture programs in India. Water bodies that do not interset villagers are targeted for use to avoid communal problems. Farmers who share common interests are identified and organized and a team leader chosen among them. An inventory of resources using the SWOT analysis is made. A participatory approach to identify major problems, socioeconomic and biophysical constraints is used and appropriate interventions are planned. This process is then evaluated and the results of the impact assessment are provided to research/extension /policy planners for setting directions and priorities for further improvement. The potential for expanding community aquaculture for generating self-employment and improving food security of the rural poor as well as improving the environmental conditions of the villages in India can be further tapped.

Beel fishery and livelihood of the local community in Rajdhala, Netrakona, Bangladesh

Baseline survey and Participatory Rural Appraisal (PRA) during January 2003 to December 2004 on the fishing community revealed that unregulated fishing, use of destructive fishing gears, poaching of fishes, difficulties encountered in enforcing fisheries regulation and the helplessness of fishers to find alternative sources of income during banned fishing period (June to October) were the major management problems. CBFM (Community Based Fisheries Management) system as an alternative management strategy has been introduced to ensure active participation of the target group-the poor fishers living around the beet who were previously deprived to get access to the beet. Establishing a leasing system for controlled access, ensuring greater user-group participation through equitable distribution of all resource benefits among members, attempting to enforce penalties for illegal fishing linked with surprise checks to enforce management regulations are some of the recent steps taken by the BMC (Beel Management Committee). Chapila fish intake by the community was 31.25 g/head/day before stocking the beel by carp fingerlings. After stocking, they consumed chapila as fish protein from 8.33 g to 20.8 g/head/day during the fishing season (November to May) indicating that due to introduction of carp fingerlings, chapila production has been decreased in 2003-2004. About 77.5% families around the beel were found to be dependent directly and/or indirectly on chapila and other indigenous fishes of the beel for their livelihood, through fishing, marketing and other activities like net and boat preparation and nets mending etc. Particularly fishers' families were found to face serious problem during non-fishing period like June to October for their livelihood. Analyzing the present research result it was also observed that other than declination in biodiversity, the fishing pressure on promising chapila of the beel was found high and that is why the production of chapila has also been decreased. To get sustainable chapila production from the heel, it is suggested to ensure successful spawning and recruitment as juveniles, and hence the chapila should be undisturbed during its breeding period from March to July, and fishing pressure on the same species needs to be reduced for obtaining sustainable fish production.