A Survey on Energy Efficient Routing Protocols in Wireless Sensor Networks

Energy efficiency is one of the critical issues in the Wireless Sensor Networks (WSNs), since sensor devices are tiny and integrated with a limited capacity battery. In most of the advanced applications, WSNs operate in very harsh areas and not under supervision of human controls. Routing protocols play a significant role in energy balancing by incorporating the techniques that can reduce control overhead, proper data aggregation method and feasible path selection. It demands a unique requirement due to its frequent topology changes and distributive nature. One of the major concerns in the design of routing protocol in WSNs is efficient energy usage and prolonging Network lifetime. This paper mainly discusses different issues related to energy efficiency in routing protocols of all categories. It incorporates most recent routing protocols which improves the energy efficiency in various application environments. This paper also provides comprehensive details of each protocol which emphasize their principles and explore their advantages and limitations. These protocols belong to different classifications based on Network Structures, communication model, topology and QoS parameters. It also includes more relevant and prominent comparisons with all recent State-of-Art works

EBDRA: energy balanced dynamic cluster routing approach for WSN

Density of nodes deployed in WSNs is based on application requirements. The redundant data collection in dense network results in more energy consumption. The Data Routing In-Network Aggregation (DRINA) is one of the recent algorithm proposed to reduce energy consumption in dense network environment by minimizing the number of communications from source to sink. Here the Data transmission is carried out by using data aggregation in cluster based environment using shortest path method. But due to inefficient cluster head selection technique, it is unable to mange cluster head failures and evades the energy drain in sensor nodes along the common static path that leads network partition. In order to overcome these problems we proposed an algorithm known as Energy Efficient Routing using Dynamic Cluster approach (EBDRA), that includes efficient cluster head selection technique and dynamic

Current situations of animal data recording, dairy improvement infrastructure, human capacity and strategic issues affecting dairy production in sub-Saharan Africa

An on-line survey on the state of existing dairy data, dairy improvement infrastructure and human capacity in Sub-Saharan Africa (SSA) was undertaken with the aim of assessing whether the state of existing animal recording, dairy improvement methods and key issues facing dairy production together with means of addressing these issues differ among countries and regions of SSA. Respondents comprised experts and practitioners in livestock production and genetic resources from research institutes, animal breeding companies, universities, non-governmental organisations and government agricultural ministries. The main dairy farming system in which the respondents were involved was mixed crop- livestock system (30.2%) and this was mainly practiced in the private land tenure system (46.3%). Data were analysed using linear model and paired student t-test in R software package. Respondents identified key issues affecting dairy production as; poor genetic assessment of imported exotic breeds and crosses in Africa (62.3%), fluctuations in milk prices within both the formal and informal markets (50.9%), no comprehensive sire ranking systems (39.6%), housing and health management regimes which adversely affect milk yield (32.1%), poor market networks for dairy products (25.5%), poor feeding (13.3%), inadequate genetic technologies (9.4%) and poor animal performance recording systems (9.4%). Respondents emphasised the need for updated breeding policies, sire ranking systems, adequate farm management systems, capacity building, across-country collaborations and joint genetic assessments of dairy breeds found in sub-Saharan Africa. The current situation of dairy production though similar for the different countries, differed in order of emphasis and magnitude across the countries and regions in sub-Saharan Africa

Degradation Kinetics of Protein Digestibility and Available Lysine During Thermal Processing of Tuna

3 pages, 2 figures, 1 tableChanges in available lysine and protein digestibility which take place during thermal processing of canned white tuna with olive oil were evaluated using a steady-state procedure. Kinetic parameters were then calculated by means of weighted nonlinear regression and the jac!+ procedures. Good agreement was found between predicted and observed values. The resulting kinetic equations can be used to evaluate, design and optimize thermal processing of tuna in oil.This work was supported by a research grant from the Comisión Interministerial de Ciencia Y Tecnología (ALI88-0145-C02-02. Spain)Peer reviewe

A randomised, blinded, trial of clopidogrel versus aspirin in patients at risk of ischaemic events (CAPRIE). CAPRIE Steering Committee

Many clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of clinical thrombotic events. Aspirin and ticlopidine have been shown to be effective, but both have potentially serious adverse effects. Clopidogrel, a new thienopyridine derivative similar to ticlopidine, is an inhibitor of platelet aggregation induced by adenosine diphosphate. METHODS: CAPRIE was a randomised, blinded, international trial designed to assess the relative efficacy of clopidogrel (75 mg once daily) and aspirin (325 mg once daily) in reducing the risk of a composite outcome cluster of ischaemic stroke, myocardial infarction, or vascular death; their relative safety was also assessed. The population studied comprised subgroups of patients with atherosclerotic vascular disease manifested as either recent ischaemic stroke, recent myocardial infarction, or symptomatic peripheral arterial disease. Patients were followed for 1 to 3 years. FINDINGS: 19,185 patients, with more than 6300 in each of the clinical subgroups, were recruited over 3 years, with a mean follow-up of 1.91 years. There were 1960 first events included in the outcome cluster on which an intention-to-treat analysis showed that patients treated with clopidogrel had an annual 5.32% risk of ischaemic stroke, myocardial infarction, or vascular death compared with 5.83% with aspirin. These rates reflect a statistically significant (p = 0.043) relative-risk reduction of 8.7% in favour of clopidogrel (95% Cl 0.3-16.5). Corresponding on-treatment analysis yielded a relative-risk reduction of 9.4%. There were no major differences in terms of safety. Reported adverse experiences in the clopidogrel and aspirin groups judged to be severe included rash (0.26% vs 0.10%), diarrhoea (0.23% vs 0.11%), upper gastrointestinal discomfort (0.97% vs 1.22%), intracranial haemorrhage (0.33% vs 0.47%), and gastrointestinal haemorrhage (0.52% vs 0.72%), respectively. There were ten (0.10%) patients in the clopidogrel group with significant reductions in neutrophils (< 1.2 x 10(9)/L) and 16 (0.17%) in the aspirin group. INTERPRETATION: Long-term administration of clopidogrel to patients with atherosclerotic vascular disease is more effective than aspirin in reducing the combined risk of ischaemic stroke, myocardial infarction, or vascular death. The overall safety profile of clopidogrel is at least as good as that of medium-dose aspirin