An Efficient Data Aggregation Algorithm for Cluster-based Sensor Network

Data aggregation in wireless sensor networks eliminates redundancy to improve bandwidth utilization and energy-efficiency of sensor nodes. One node, called the cluster leader, collects data from surrounding nodes and then sends the summarized information to upstream nodes. In this paper, we propose an algorithm to select a cluster leader that will perform data aggregation in a partially connected sensor network. The algorithm reduces the traffic flow inside the network by adaptively selecting the shortest route for packet routing to the cluster leader. We also describe a simulation framework for functional analysis of WSN applications taking our proposed algorithm as an exampl

A comparison of software platforms for Wireless Sensor Networks: MANTIS, TinyOS and ZigBee

Wireless sensor networks are characterized by very tight code size and power constraints, and by a lack of well-established standard software development platforms such as Posix. In this paper, we present a comparative study between a few fairly different such platforms, namely MANTIS, TinyOS and ZigBee, when considering them from the application developer's perspective, i.e. by focusing mostly on functional aspects, rather than on performance or code size. In other words, we compare both the tasking model used by these platforms and the API libraries they offer. Sensor network applications are basically event based, so most of the software platforms are also built on considering event handling mechanism, however some use a more traditional thread based model. In this paper, we consider implementations of a simple generic application in MAN- TIS, TinyOS and the Ember ZigBee development framework, with the goal of depicting major differences between these platforms, and suggesting a programming style aimed at maximizing portability between them

Using Hydrophilic Ionic Liquid, [bmim]BF4 – Ethylene Glycol System as a Novel Media for the Rapid Synthesis of Copper Nanoparticles

In this work, we present a novel method for the synthesis of copper nanoparticles. We utilize the charge compensatory effect of ionic liquid [bmim]BF4 in conjunction with ethylene glycol for providing electro-steric stabilization to copper nanoparticles prepared from copper sulphate using hydrazine hydrate as a reducing agent. The formed copper nanoparticles showed extended stability over a period of one year. Copper nanoparticles thus prepared were characterized by powder X-ray diffraction measurements (pXRD), transmission electron microscopy (TEM) and quasi elastic light scattering (QELS) techniques. Powder X-ray diffraction (pXRD) analysis revealed relevant Bragg's reflection for crystal structure of copper. Powder X-ray diffraction plots also revealed no oxidized material of copper nanoparticles. TEM showed nearly uniform distribution of the particles in methanol and confirmed by QELS. Typical applications of copper nanoparticles include uses in conductive films, lubrication and nanofluids. Currently efforts are under way in our laboratory for using these nanoparticles as catalysts for a variety of organic reactions

Prevalence and Determinants of Metabolic Syndrome among Women in Chinese Rural Areas

BACKGROUND AND AIMS: Metabolic syndrome (MS) is prevalent in recent years but few data is reported in the rural areas in China. The aim of this study was to examine MS prevalence and its risk factors among women in rural China. METHODS AND RESULTS: The Nantong Metabolic Syndrome Study (NMSS), a population based cross-sectional study, was conducted during 2007-2008 in Nantong, China. In person interviews, blood glucose and lipid measurements were completed for 13,505 female participants aged 18-74 years. The International Diabetes Federation (IDF), the US Third Report of the National Cholesterol Education Program, the Adult Treatment Panel (ATPIII) and modified ATPIII for Asian population has determined three criteria of MS. These criteria for MS were used and compared in this study. The prevalence of MS was 22.0%, 16.9% and 23.3% according to IDF, ATPIII and ATPIII-modified criteria, respectively. Levels of agreement of these criteria for MS were above 0.75. We found that vigorous-intensity of occupational physical activity was associated with a low prevalence of MS with OR of 0.76 (95% confidence interval (CI): 0.63-0.91). Rice wine drinkers (alcohol >12.8 g/day) had about 34% low risks of developing MS with OR of 0.66 (95% CI: 0.48-0.91), compared with non-drinkers. Odds ratio of MS was 1.81 (95% CI: 1.15-2.84) in women who smoked more than 20 pack-years, compared to non-smokers. Odds ratio of MS was 1.56 (95% CI: 1.25-1.95) in women who had familial history of diseases, including hypertension, diabetes and stroke, compared to women without familial history of those diseases. CONCLUSION: MS is highly prevalent among women in rural China. Both physical activity and rice wine consumption play a protective role, while family history and smoking are risk factors in MS development. Educational programs should be established for promoting healthy lifestyles and appropriate interventions in rural China

Productivity and Resource Use Efficiency of Boro Rice Production

This study was attempted to measure and compare resource use efficiency and relative productivity of farming under different tenure conditions in an area of Bhola district. A random sampling technique was used in the study. Sample farmers were classified as owner, crop share tenant and cash tenant farmers. A total of 90 samples, 30 from each class were selected on the basis of random sampling technique. The study explored the difference in the efficiency and productivity among owner, cash tenant and crop share tenant. Total cash expenses as well as total gross costs for producing HYV Boro rice was highest in owner farms and lowest in crop share tenant's farm. When individual inputs were concerned it was observed that expenses on human labor shared a major portion of expenses in the production of HYV Boro rice where owner operators used more hired labor in compare to other groups. However, the cash tenant farmers were more efficient than owner and crop share tenant farmers. Due to poor resource base the crop share tenants were unable to invest on modern farm inputs. It may be mentioned that in Bangladesh the predominant tenancy arrangement is share cropping, which is an inefficient form of tenure arrangement in compare to cash tenancy