38 research outputs found
Performance analysis of a highly available home agent in mobile networks
Network Mobility as a service is provided by the NEMO protocol in IPv6 environments. NEMO is an extension to MIPv6, and thus inherits the same reliability problems of MIPv6. MIPv6 is not reliable because the Home Agent (HA) is a single point of failure. In order to provide real-time services for MIPv6 networks, reliability should be considered as part of any high availability solution used to deploy Mobile IPv6 networks. Approach: Many approaches have been taken to solve the problem of HA as a single point of failure. In our proposed solution, failure detection and recovery is handled by the home agent. Therefore, recovery is transparent to the mobile network. Results: In this work we opted for using HA redundancy to provide a highly available home agent solution which achieves recovery times suitable for real-time applications
Synthesized copper oxide nanoparticles via the green route act as antagonists to pathogenic root-knot nematode, Meloidogyne incognita
This investigation explains the green synthesis, characterization and biocontrol potential of copper oxide nanoparticles (CuONPs) against second-stage juveniles (J2s) of root-knot nematode, Meloidogyne incognita infesting chickpea. Mono-disperse, spherical, pure CuONPs were synthesized from Jatropha curcas leaf with particle sizes ranging from 5 to 15 nm in diameter. Antagonistic activities of synthesized CuONPs were studied against Meloidogyne incognita. The highest mortality of J2s was found in the 200 ppm concentration of CuONPs at 24 h of exposure. The exact concentration also showed maximum inhibition of J2s hatching from egg masses after six days of exposure. It was worth noting that 25 ppm concentration was the least effective. The pot experiment showed that CuONPs significantly reduced the root infection caused by M. incognita and enhanced chickpea plants’ growth and physiological attributes (Chlorophyll and carotenoid content). The results depicted when the concentration of CuONPs was increased, J2s mortality rate was also increased. We highlighted the antinematode influence of green synthesized CuONPs. Thus, it will offer an excellent eco-friendly strategy to optimize yield under pathogens attack and provide prospects of green synthesized-based nanoparticles development for pests control. Plants mediated CuONPs will also help in resolving the current toxicity concerns and future challenges in the agriculture
Effect of individual, simultaneous and sequential inoculation of pseudomonas fluorescens and meloidogyne incognita on growth, biochemical, enzymatic and nonenzymatic antioxidants of tomato (Solanum lycopersicum l.)
This study was conducted on tomato (Solanum lycopersicum cv. K-21) to investigate the bioprotective nature of Pseudomonas fluorescens and its interactive effects with Meloidogyne incognita in terms of growth biomarkers, changes in biochemical attributes and modulation in antioxidant enzymes of the tomato plant. In this study, we grew tomato plants with M. incognita and P. fluorescens in separate pots, simultaneously and sequentially (15 days prior or post) after 15 days of seed sowing. The sequential inoculation of Mi15→Pf maximally increased the root-knot index and decreased the nematode population. It was also noted that inoculation suppressed the plant growth biomarkers in comparison to control. However, maximum suppression in nematode reproduction and increment in growth and physiological attributes were observed when P. fluorescens was applied 15 days prior to the nematode (Pf15→Mi) as compared to control. All the treatments showed an increase in antioxidant enzymes. Expression of phenol content and defensive enzymes such as peroxidase (POX) and superoxide dismutase (SOD) increased, in contrast to a significant reduction in malondialdehyde (MDA) and hydrogen peroxide (H2 O2 ) contents when compared with the untreated inoculated plants. However, the highest levels of POX and SOD, and a lowest of phenol, MDA and H2 O2 were displayed in the treatment Pf15→Mi, followed by Mi+Pf and Mi15→Pf
Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017
A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5) million) in 2000 to 6.0% (55.5 (44.8–67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic
Variation in Direct Solar Irradiation with Relative Humidity and Atmospheric Temperature
A class first Pyranometer was used to measure the direct solar irradiation and the obtained results were analyzed. Separate sensors were used to measure the relative humidity and the atmospheric temperature (RH/AT sensors). The measurements were conducted for the whole year of 2013. The author analyzed the collected solar data during one day, month, and year. The maximum, minimum, average, and accumulative solar irradiation (SR) were calculated and analyzed with connection to relative humidity and atmospheric temperature. The author found that April was characterized by the average maximum solar irradiation (SR= 1112±1W/m2), May had the maximum SR accumulation (13276552± 1W/m2). The maximum average percentage relative humidity found in July (% RH = 97± 3%), while the minimum average % RH is in December (% RH = 25± 3%). In May, the maximum average atmospheric temperature was 36.0 ± 0.6°C, while the average minimum was in January (AT= 19.1 ± 0.6°C). The total accumulation of solar flux during the year 2013 is 222 ± 1MW/m2
Removing Heavy Metals Through Different Types of Soils and Marble Powder Found in Oman
In this research, adsorption followed by filtration was used for removing heavy metals (Cu, Zn, Mn, and Cr) from the polluted water. Three types of soils (silty, sandy and clay) and three types of marble powder (pure, impure, marble-granite mix) were used as an adsorbent. The soil and marble samples were collected from different regions of Oman. The maximum adsorption obtained was 96.01% for Zn using pure marble powder and the minimum adsorption obtained was 6.70% for Mn using impure marble powder. Through different soils, the maximum adsorption of 88.61% was achieved for Zn using clay and the lowest one is for Cr 16.51% using silty soil. The results suggest that among the marble powders, the pure ones show the maximum (96.01% for Zn) and marble-granite show the minimum (Mn 6.70%) adsorption performance. Among the adsorbents, Zn is the best adsorbate (96.01%) while the worst among the group is Mn, which merely adsorbed 6.70% with the selected adsorbents
Energy Efficient Optimal Design of Waste Solvent Recovery Process in Semiconductor Industry Using Enhanced Vacuum Distillation
Comparative analysis of IEEE 802.11g multimedia multicast performance using RTP with an implemented test-bed
In network layer protocols, the most efficient way of sending similar packets to a group of nodes is via multicast. Multicast is a profound concept that has been around for some time and has seen through its implementation in various aspects of today’s network access technology. The IEEE 802.11 wireless standards, however, loosely honor IP layer multicast packets by encapsulating them in broadcast frames. This in turn degrades the 802.11 network access bandwidth capacity and further decreases its data transmission reliability. An enhancement workaround which has been devised was to encapsulate multicast packets in a unicast MAC layer frame. In addition, RTP was also observed to be an enabler to better user experience in multicast streaming. In this paper, we investigate the 802.11g multicast performance with and without the enhanced multicast mechanism. We further expand our investigation by implementing RTP during the multimedia multicast stream and without it. Our results lead us to conclude that there are significant advantages of using both the enhanced multicast mechanism and RTP during a multicast streaming via the 802.11g wireless standard
Sequential coordinate random search for optimal operation of LNG (liquefied natural gas) plant
This study exploits the sequential coordinate randomization search method for optimizing LNG (liquefied natural gas) process plants. The coordinate search is based on the idea of minimizing the multivariable function considering one variable at a time. The random element is incorporated in the coordinated search for an exhaustive exploration of decision variable space. A simple implementation with few operating parameters makes the proposed approach suitable for the optimization of highly non-linear LNG process plants. The efficacy of the proposed methodology was tested on the well-known SMR (single mixed refrigerant) and propane pre-cooled mixed refrigerant (C3MR) process of NG liquefaction. The main decision variables in SMR and C3MR process plants were identified and optimized in terms of the compression energy. The results were compared with the heuristic results, which revealed the superiority, simplicity and suitability of the proposed sequential coordinate random search algorithm for LNG process plants