Image scoring in ad-hoc networks : an investigation on realistic settings

Encouraging cooperation in distributed Multi-Agent Systems (MAS) remains an open problem. Emergent application domains such as Mobile Ad-hoc Networks (MANETs) are characterised by constraints including sparse connectivity and a lack of direct interaction history. Image scoring, a simple model of reputation proposed by Nowak and Sigmund, exhibits low space and time complexity and promotes cooperation through indirect reciprocity, in which an agent can expect cooperation in the future without repeat interactions with the same partners. The low overheads of image scoring make it a promising technique for ad-hoc networking domains. However, the original investigation of Nowak and Sigmund is limited in that it (i) used a simple idealised setting, (ii) did not consider the effects of incomplete information on the mechanism’s efficacy, and (iii) did not consider the impact of the network topology connecting agents. We address these limitations by investigating more realistic values for the number of interactions agents engage in, and show that incomplete information can cause significant errors in decision making. As the proportion of incorrect decisions rises, the efficacy of image scoring falls and selfishness becomes more dominant. We evaluate image scoring on three different connection topologies: (i) completely connected, which closely approximates Nowak and Sigmund’s original setup, (ii) random, with each pair of nodes connected with a constant probability, and (iii) scale-free, which is known to model a number of real world environments including MANETs

The wages of CIN

Aneuploidy and chromosome instability (CIN) are hallmarks of the majority of solid tumors, but the relationship between them is not well understood. In this issue, Thompson and Compton (Thompson, S.L., and D.A. Compton. 2008. Examining the link between chromosomal instability and aneuploidy in human cells. J. Cell. Biol. 180:665–672) investigate the mechanism of CIN in cancer cells and find that CIN arises primarily from defective kinetochore–spindle attachments that evade detection by the spindle checkpoint and persist into anaphase. They also explore the consequences of artificially elevating chromosome missegregation in otherwise karyotypically normal cells. Their finding that induced aneuploidy is rapidly selected against suggests that the persistence of aneuploid cells in tumors requires not only chromosome missegregation but also additional, as yet poorly defined events

Effect of Partial Rootzone Drying Irrigation on Nutrient Concentration in Leaves, Photosynthesis, Photosynthesis Active Radiation and Yield of Sorghum Cultivar

The effects of partial rootzone drying irrigation technique on nutrient concentration in leaves, photosynthesis, photosynthetic active radiation and yield of sorghum grown on Rhu Tapai and Rengam series soil were examined at Control Environment House, Faculty of Agrotechnology and Food Science, University Malaysia Terengganu. The experiments partial rootzone drying irrigation consisted of a factorial combination of irrigation regimes and soil types laid in a randomized complete block design with eight treatments. Irrigation regimes were at four levels namely: I100, I75, I50 and I25 and the soil types were at two levels namely: Rhu Tapai and Rengam series soil.  The treatments were randomly assigned to experimental pots and replicated four times. All agronomic practices starting from planting of sorghum to harvesting were adhered to and photosynthesis, photosynthetic active radiation and yield parameters were recorded for the experiment. The result of the study shows that, sorghum performed better under partial rootzone drying technique. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of photosynthesis, photosynthetic active radiation and yield parameters compared to I50 and I25 irrigation regimes. The study also revealed that there was no significant different between the two types of soil used for the study. The study, therefore, recommended the use of I75 percent regulated deficit irrigation for optimizing sorghum yield production in semi-arid regions. Keywords:Partial rootzone drying irrigation, nutrient concentration, photosynthesis,    photosynthetic active radiation, yield, sorghu

Effect of Partial Rootzone Drying Irrigation on Nutrient Concentration in Leaves, Photosynthesis, Photosynthesis Active Radiation and Yield of Sorghum Cultivar

The effects of partial rootzone drying irrigation technique on nutrient concentration in leaves, photosynthesis, photosynthetic active radiation and yield of sorghum grown on Rhu Tapai and Rengam series soil were examined at Control Environment House, Faculty of Agrotechnology and Food Science, University Malaysia Terengganu. The experiments partial rootzone drying irrigation consisted of a factorial combination of irrigation regimes and soil types laid in a randomized complete block design with eight treatments. Irrigation regimes were at four levels namely: I100, I75, I50 and I25 and the soil types were at two levels namely: Rhu Tapai and Rengam series soil.  The treatments were randomly assigned to experimental pots and replicated four times. All agronomic practices starting from planting of sorghum to harvesting were adhered to and photosynthesis, photosynthetic active radiation and yield parameters were recorded for the experiment. The result of the study shows that, sorghum performed better under partial rootzone drying technique. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of photosynthesis, photosynthetic active radiation and yield parameters compared to I50 and I25 irrigation regimes. The study also revealed that there was no significant different between the two types of soil used for the study. The study, therefore, recommended the use of I75 percent regulated deficit irrigation for optimizing sorghum yield production in semi-arid regions. Keywords:Partial rootzone drying irrigation, nutrient concentration, photosynthesis,    photosynthetic active radiation, yield, sorghu

Effect of Regulated Deficit Irrigation on Photosynthesis, Photosynthetic Active Radiation on Yield of Sorghum Cultivar

The effects of regulated deficit irrigation technique on photosynthesis, photosynthetic active radiation and yield of sorghum grown on Rhu Tapai and Rengam series soil were examined in a Control Environment House at the Faculty of Agrotechnology and Food Science, University Malaysia Terengganu. The experiments regulated deficit irrigation consisted of a factorial combination of irrigation regimes and soil types laid in a randomized complete block design with eight treatments for. Irrigation regimes were at four levels namely: I100, I75, I50 and I25 and the soil types were at two levels namely: Rhu Tapai and Rengam series soil.  The treatments were randomly assigned to experimental pots and replicated four times. All agronomic practices starting from planting of sorghum to harvesting were adhered to and photosynthesis, photosynthetic active radiation and yield parameters were recorded for the experiment. The result of the study shows that sorghum performed better under regulated deficit irrigation technique. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of photosynthesis, photosynthetic active radiation and yield parameters compared to I50 and I25 irrigation regimes. The study also revealed that there was no significant different between the two types of soil used for the study. The study, therefore, recommended the use of I75 percent regulated deficit irrigation for optimizing sorghum yield production in semi-arid regions. Keywords: Regulated deficit Irrigation, photosynthesis, photosynthetic active radiation, yield, sorghu

Phosphate and Sulphate Adsorptions in Bungor Series Soil

Phosphate and sulphate adsorption in Bungor series soil were studied using soil sample and equilibrated with 0.1 M CaCl2 containing concentrations of phosphate and sulphate of   0, 50, 100, 200, 400, 800 and 1200µg-1 phosphate and sulphate was determined using double beam spectrophotometer. The result of the study shows that Bungor series soil has high capacity to adsorb phosphate and sulphate ions.. Keywords: Phosphate, sulphate, adsorption, Bungor series soi

Effect of Regulated Deficit Irrigation on Nutrient Concentration in Leaves,Growth and Yield of Sorghum

The effects of regulated deficit irrigation technique on nutrient concentration in leaves, growth and yield of sorghum was examined in a greenhouse at the School of Science and Food Technology, Universiti Malaysia Terengganu. The experiments regulated deficit irrigation (RDI) consisted of a factorial combination of irrigation regimes and soil types laid in a randomised complete block design with eight treatments for each experiment which resulted into a total of sixteen treatments. Irrigation regimes were at four levels namely: I100, I75, I50 and I25 and the soil types were at two levels namely: Rhu Tapai and Rengam soil series. The treatments were randomly assigned to experimental pots and replicated four times. A total of thirty two pots were used for the study. All agronomic practices starting from land preparation to harvesting were adhered to and growth parameters were recorded for both experiments. The result of the study shows that sorghum performance improved under regulated deficit irrigation techniques. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of growth parameters, crop water use efficiency under RDI and compared to I50 and I25 irrigation regimes. The study also revealed that there were interaction effects of deficit irrigation and the two types of soil on some of the parameters used for the study. The study, therefore, recommended the use of I75, for optimizing sorghum growth in this agro ecological zone. Keywords: Regulated deficit irrigation, Nutrient Concentration, Growth, Yield, Sorghum, Water use efficiency

Modeling Probability of Path Loss for DSDV, OLSR and DYMO above 802.11 and 802.11p

This paper presents path loss model along with framework for probability distribution function for VANETs. Furthermore, we simulate three routing protocols Destination Sequenced Distance Vector (DSDV), Optimized Link State Routing (OLSR) and Dynamic MANET On-demand (DYMO) in NS-2 to evaluate and compare their performance using two Mac-layer Protocols 802.11 and 802.11p. A novel approach of this work is modifications in existing parameters to achieve high efficiency. After extensive simulations, we observe that DSDV out performs with 802.11p while DYMO gives best performance with 802.11.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

Lubrication effects on the flow of wet granular materials

We investigate the dynamics of a partially saturated grain-liquid mixture with a rotating drum apparatus. The drum is partially filled with the mixture and then rotated about its horizontal axis. We focus on the continous avalanching regime and measure the impact of volume fraction and viscosity of the liquid on the dynamic surface angle. The inclination angle of the surface is observed to increase sharply to a peak and then decrease as a function of liquid volume fraction. The height of the peak is observed to increase with rotation rate. For higher liquid volume fractions, the inclination angle of the surface can decrease with viscosity before increasing. The viscosity where the minima occurs decreases with the rotation rate of the drum. Limited measurements of the flow depth were made, and these were observed to show only fractional changes with volume fraction and rotation speeds. We show that the qualitative features of our observations can be understood by analyzing the effect of lubrication forces on the timescale over which particles come in contact.Comment: 7 pages, 8 figure