Integrating fish resources to agro-ecosystem analyses

In October 2005, a consortium of partners led by the International Water Management Institute (IWMI) proposed a project aimed at integrating fish resources management in agricultural management in the Tonle Sap area. This 2-years project assistance was accepted for funding by the Challenge Program on Water and Food and started in January 2008. The overall goal of this project is to improve allocation and use of water in combined farming and fishing systems in order to enhance food security of rural communities and water productivity. The general objectives of the Fisheries component are: 1) to contribute to the review of existing fisheries and aquaculture information, assessment and data collection systems and existing databases from a fisheries perspective 2) to determine key questions that could be asked at the commune level that would enable the identification of fisheries issues for different agroecosystem zones. These would include both threats and potential threats to fisheries based on key ecological variables and opportunities that fisheries and aquaculture could represent in local livelihoods.Research, Lake fisheries, Agropisciculture, Ecosystems, Analysis, Cambodia, Tonle Sap L.,

Superconductivity under pressure in the Dirac semimetal PdTe2

The Dirac semimetal PdTe$_2$ was recently reported to be a type-I superconductor ($T_c =$1.64 K, $\mu_0 H_c (0) = 13.6$ mT) with unusual superconductivity of the surface sheath. We here report a high-pressure study, $p \leq 2.5$ GPa, of the superconducting phase diagram extracted from ac-susceptibility and transport measurements on single crystalline samples. $T_c (p)$ shows a pronounced non-monotonous variation with a maximum $T_c =$1.91 K around 0.91 GPa, followed by a gradual decrease to 1.27 K at 2.5 GPa. The critical field of bulk superconductivity in the limit $T \rightarrow 0$, $H_c(0,p)$, follows a similar trend and consequently the $H_c(T,p)$-curves under pressure collapse on a single curve: $H_c(T,p)=H_c(0,p)[1-(T/T_c(p))^2]$. Surface superconductivity is robust under pressure as demonstrated by the large superconducting screening signal that persists for applied dc-fields $H_a > H_c$. Surprisingly, for $p \geq 1.41$ GPa the superconducting transition temperature at the surface $T_c^S$ is larger than $T_c$ of the bulk. Therefore surface superconductivity may possibly have a non-trivial nature and is connected to the topological surface states detected by ARPES. We compare the measured pressure variation of $T_c$ with recent results from band structure calculations and discuss the importance of a Van Hove singularity.Comment: manuscript 9 pages with 8 figures + supplemental material 3 pages with 6 figure

Time series forecasting of the number of Malaysia Airlines and AirAsia passengers

The standard practice in forecasting process involved by fitting a model and further analysis on the residuals. If we know the distributional behaviour of the time series data, it can help us to directly analyse the model identification, parameter estimation, and model checking. In this paper, we want to compare the distributional behaviour data from the number of Malaysia Airlines (MAS) and AirAsia passenger’s. From the previous research, the AirAsia passengers are govern by geometric Brownian motion (GBM). The data were normally distributed, stationary and independent. Then, GBM was used to forecast the number of AirAsia passenger’s. The same methods were applied to MAS data and the results then were compared. Unfortunately, the MAS data were not govern by GBM. Then, the standard approach in time series forecasting will be applied to MAS data. From this comparison, we can conclude that the number of AirAsia passengers are always in peak season rather than MAS passengers

Practical Aspects of Automatic Orientation Analysis of Micrographs

Techniques to analyse the orientation of particulate materials as observed in the scanning electron microscope are reviewed in this paper. Emphasis is placed on digital imaging, processing, and analysis methods, but many secondary electron images are not amenable to traditional image processing as adequate thresholding is often difficult to achieve. Evaluation of the intensity gradient at each pixel offers an alternative approach, and this method is described in detail including the latest developments to generalize the technique. Practical points in the acquisition, processing and analysis of the images are considered and several images, including both synthetically generated and actual back-scattered images of soil particle arrangements are presented. A discussion of methods to display the results is included as are possible future developments

Detection and characterisation of delamination damage propagation in woven glass fibre reinforced polymer composite using thermoelastic response mapping

This paper details a study on the application of Thermoelastic Stress Analysis (TSA) for the investigation of delamination damage propagation in glass fibre reinforced composite materials. A woven Glass (0/90)/ Epoxy composite sample containing a purposely created delamination was subjected to a step-cyclic loading (varying mean level) whilst monitoring the thermoelastic response of the sample with an infrared camera. A finite element analysis (FEA) was performed using cohesive elements to simulate the propagation of the delamination under a monotonically increasing axial load. It is shown that the delamination crack length inferred from the TSA results is consistent with microscopic analysis of the sample, and that the measured crack growth rate is in reasonable agreement with simulation results

Silicon isotopes in Antarctic sponges : an interlaboratory comparison

Cycling of deepwater silicon (Si) within the Southern Ocean, and its transport into other ocean basins, may be an important player in the uptake of atmospheric carbon, and global climate. Recent work has shown that the Si isotope (denoted by δ29Si or δ30Si) composition of deep sea sponges reflects the availability of dissolved Si during growth, and is a potential proxy for past deep and intermediate water silicic acid concentrations. As with any geochemical tool, it is essential to ensure analytical precision and accuracy, and consistency between methodologies and laboratories. Analytical bias may exist between laboratories, and sponge material may have matrix effects leading to offsets between samples and standards. Here, we report an interlaboratory evaluation of Si isotopes in Antarctic and sub-Antarctic sponges. We review independent methods for measuring Si isotopes in sponge spicules. Our results show that separate subsamples of non-homogenized sponges measured by three methods yield isotopic values within analytical error for over 80% of specimens. The relationship between δ29Si and δ30Si in sponges is consistent with kinetic fractionation during biomineralization. Sponge Si isotope analyses show potential as palaeoceaongraphic archives, and we suggest Southern Ocean sponge material would form a useful additional reference standard for future spicule analyses

GPU-based multiple back propagation for big data problems

The big data era has become known for its abundance in rapidly generated data of varying formats and sizes. With this awareness, interest in data analytics and more specifically predictive analytics has received increased attention lately. However, the massive sample sizes and high dimensionality peculiar with these datasets has challenged the overall performance of one of the most important components of predictive analytics of our present time, Machine Learning. Given that dimensionality reduction has been heavily applied to the problems of high dimensionality, this work presents an improved scheme of GPU based Multiple Back Propagation (MBP) with feature selection for big high dimensional data problems. Elastic Net was used for automatic feature selection of high dimensional biomedical datasets before classification with GPU based MBP and experimental results show an improved performance over the previous scheme with MBP