Metal-insulator transition and electrically-driven memristive characteristics of SmNiO3 thin films

The correlated oxide SmNiO3 (SNO) exhibits an insulator to metal transition (MIT) at 130 {\deg}C in bulk form. We report on synthesis and electron transport in SNO films deposited on LaAlO3 (LAO) and Si single crystals. X-ray diffraction studies show that compressively strained single-phase SNO grows epitaxially on LAO while on Si, mixed oxide phases are observed. MIT is observed in resistance-temperature measurements in films grown on both substrates, with charge transport in-plane for LAO/SNO films and out-of-plane for Si/SNO films. Electrically-driven memristive behavior is realized in LAO/SNO films, suggesting that SNO may be relevant for neuromorphic devices

ESTIMATION OF COEFFICIENT OF ISOTHERMAL OIL COMPRESSIBILITY AT RESERVOIR PRESSURE GREATER THAN BUBBLE POINT PRESSURE USING GROUP METHOD OF DATA HANDLING

The procedures of determining the oil compressibility through PVT analyses are usually costly and time consuming. Therefore, various empirical correlations were designed in order to accurately estimate the oil compressibility. This project focuses on designing a model correlation which could accurately predict the oil compressibility coefficient above bubble point pressure. The new model correlation using the Polynomial GMDH method will be compared in terms of its accuracy and reliability with actual PVT data and also current oil compressibility correlation using different types of analysis such as trend analysis, group error analysis, statistical error analysis and graphical error analysis. A total number of 195 data sets were collected from the Mediterranean Basin, Africa, Persian Gulf and the North Sea and after data filtration 183 data were used and divided into 3 sections of training, validation and testing data sets in a ratio of 2:1:1. Using the Polynomial GMDH technique, 3 input parameters were found to be affecting the outputs which are Reservoir Pressure, Solution GOR and Bubble Point Pressure. The new model correlations were then compared with the other correlations and it surpasses all of the other correlations in terms accuracy by having the lowest Root Mean Square Error, Average Percent Relative Errors, Average Absolute Percent Relative Error and Standard Deviations. Furthermore, it is worth to note that the Absolute Percent Relative Error was the main statistical analysis criteria in this study and the Polynomial GMDH model obtained the lowest value. Overall, the Polynomial GMDH model is a robust model and can be affectively applied within its trained data ranges

Conductivity noise study of the insulator-metal transition and phase co-existence in epitaxial samarium nickelate thin films

Interaction between the lattice and the orbital degrees of freedom not only makes rare-earth nickelates unusually "bad metal", but also introduces a temperature driven insulator-metal phase transition. Here we investigate this insulator-metal phase transition in thin films of $\mathrm{SmNiO_3}$ using the slow time dependent fluctuations (noise) in resistivity. The normalized magnitude of noise is found to be extremely large, being nearly eight orders of magnitude higher than thin films of common disordered metallic systems, and indicates electrical conduction via classical percolation in a spatially inhomogeneous medium. The higher order statistics of the fluctuations indicate a strong non-Gaussian component of noise close to the transition, attributing the inhomogeneity to co-existence of the metallic and insulating phases. Our experiment offers a new insight on the impact of lattice-orbital coupling on the microscopic mechanism of electron transport in the rare-earth nickelates.Comment: 5 pages, 4 figure

The potential of community fish refuges (CFRs) in rice field agro-ecosystems for improving food and nutrition security in the Tonle Sap region

The fisheries sector in Cambodia contributes 8%–12% to national GDP and 25% - 30% to agricultural GDP, with an estimated 4.5 million people involved in fishing and associated trades. Fish and other aquatic animals are important food sources, contributing an estimated national average of 60% - 70% of total animal protein intake. Of the 2013 total fish production, 550,000 metric tons were harvested from freshwater habitats, of which rice field fisheries and small-scale family fisheries contributed approximately 20%. The productivity and value of rice field fisheries to households in rural Cambodia has been highlighted in a number of previous studies. The Fisheries Administration of the Ministry of Agriculture, Forestry and Fisheries plans to increase productivity from rice field fisheries and aquaculture at an annual rate of 15% to maintain supply for a growing population. This report draws mainly on the baseline and monitoring data from the Rice Field Fisheries Enhancement Project (RFFEP) during its implementation between 2012 and 2014. Reference is also made to the Fish on Farms project to highlight the relative contribution of fish from small-scale aquaculture compared to wild-caught fish

Music sight-reading expertise, visually disrupted score and eye movements

Previous studies have shown that performance at a defined level of music sight reading for pianists (6th Grade) is predictive of eye movement patterns (Waters, 1998) and that such patterns resemble those of text reading experts (Furneaux & Land, 1999; Sloboda, 1974; Truitt, 1997; Wolf, 1976). However, little is known about how expertise might affect eye movement patterns when the score has been visually disrupted using notational features that are unexpected or outside conventional presentation.The current project examined the effect of altering features of the music score on eye movement patterns of expert and non-expert music sight readers. Participants sight read specifically composed musical excerpts, which were then re-presented with the bar-lines removed, altered inter-note spacing and unpredictable beaming directions. Fixation and saccade characteristics were measured and compared between the two performances. It was expected that expert music sight readers would be most affected when the score was disrupted as they would be less capable of grouping notes into familiar, single units for efficient visual processing. Expert sight readers performed significantly faster than non-experts in both conditions: p<0.0001. Saccadic latency increased significantly for experts in the disrupted condition: p=0.0259, while non-experts increased slightly, not reaching significance. This suggests that the disruption of visual expectation was sufficient to cause a lengthening of saccade programming in the experts - an indication of interference with the chunking process. The resultant EM patterns for the non-experts demonstrated heightened non-expert behaviours: increased fixations of shorter duration.