Cointegration and Causality Analysis of World Vegetable Oil and Crude Oil Prices

Because of the recent soaring petroleum price and growing environmental concerns, biodiesel has become an important alternative fuel. Biodiesel is the mono alky esters made from a vegetable oil, such as soybean or rapeseed oil, or sometimes from animal fats. The escalation in world petroleum price has stimulated the demand for biodiesel, which consequently expanded the use of vegetable oils. This paper investigates the long-run interdependence between major edible oil prices and examines the dynamic relationship between vegetable and crude oil prices. The data consists of 378 weekly observations extending from the first week of January in 1999 to the fourth week of March in 2006. We apply time-series analytical mechanisms and directed acyclic graphs to four major traded edible oils prices, including soybean, sunflower, rapeseed and palm oils, along with one weighted average world crude oil price. Tentative results suggest one long-run cointegration relationship among those five oil prices. Also, the edible oil markets are well linked in contemporaneous time with the palm oil market initiating the new information; however, soybean oil price dominates the edible oil markets in the long run. The influence of crude oil price on edible oil prices is not significant over the study period.Resource /Energy Economics and Policy,

Application of Electrical Properties to Differentiate Lard From Tallow and Palm Oil

This study aimed to differentiate lard from tallow and palm oil based on its electrical properties, namely conductance, impedance and capacitance. These properties were measured at spectra frequencies of 4.20 to 5.00 MHz in room temperature (26-27 oC). Statistic multivariate that consist on principal component analysis (PCA) and cluster analysis (CA) were used to evaluate the data. The results showed that lard and tallow can be differentiated using whole parameters electrical properties of materials. On the other hand, lard and palm oil can only be differentiated using part of the material electrical properties. Good performance of differentiation process was obtained using PCA model at 4.91 to 4.98 MHz. The first two components of PCA, which was derived from conductance, impedance and capacitance, contributed more than 90% of the total variances. CA showed that lard and tallow are different groups based on the Euclidean distance of each electrical properties. This technique can be potentially developed as an electrical sensor for differentiation lard to tallow and palm oil

Hubungan Antara Kadar Yodium Urin Dan Memori Jangka Pendek Pada Anak Sekolah Dasar Di Daerah Endemis Gaky

Background: Good short term memory ability is essential in order to improve children's academic achievement. Decrease in short term memory function can be found in children on Iodine Deficiency Disorders (IDD) endemic area. Urinary Iodine (UI) concentrations is the recommended method to determine status of IDD endemic area.Aim: To determine the correlation of urinary iodine concentrations and short term memory in elementary school children in IDD endemic area.Methods: This was an analytic observational study with cross sectional design. Samples were 50 elementary school children aged 9-11 years old who lived in IDD endemic area in Sub Kertek, Wonosobo Regency, Central Java Province. Short term memory function was evaluated by Digit Span test. Spot urine samples were retrieved to assess UI concentrations. Spearman test were used for statistical analysis.Results: Median ± deviation standard digit span forward score 4.00 ± 0.89, digit span backward score 2.00 ± 0.35, digit span scaled score 5.00 ± 1.64, and UI concentrations 287.00 ± 64.49 μg/L. There were significant correlation between UI concentrations with digit span forward score (p=0.009) and digit span scaled score (p=0.009) but not significant with digit span backward score (p=0.136)Conclusion: There were positive correlation between UI concentrations and short term memory in elementary school children on IDD endemic area

Analyzing the Economics Values of An Alternative Preprocessing Facility in the Biomass Feedstocks - Biorefinery Supply Chain

It is generally believed that preprocessing procedure can reduce the transportation and storage costs of biomass feedstock for biofuel production by condensing the feedstock’s size. However, the capital costs of preprocessing facilities could be significant in the feedstock logistics system. Applying a GIS and mixed-integer mathematical programming model, this study evaluates the economic values of a preprocessing technology, stretch‐wrap baling, in the biomass feedstock supply chain for a potential commercial-scale switchgrass biorefinery in East Tennessee. Preliminary results suggest that the stretch-wrap baling equipment outperforms the conventional hay harvest methods in terms of total delivered costs. Although the densification process involves additional capital and operation costs, the total delivered costs of switchgrass for a 25- million-gallon per year biorefinery in the preprocessing system is 12% − 21% lower than various logistic methods using conventional hay equipments.Biomass feedstock, cellulosic biofuel, logistic costs, preprocessing technology, Crop Production/Industries, Resource /Energy Economics and Policy, Q16, D24,

Phase separation and electron pairing in repulsive Hubbard clusters

Exact thermal studies of small (4-site, 5-site and 8-site) Hubbard clusters with local electron repulsion yield intriguing insight into phase separation, charge-spin separation, pseudogaps, condensation, in particular, pairing fluctuations away from half filling (near optimal doping). These exact calculations, carried out in canonical (i.e. for fixed electron number N) and grand canonical (i.e. fixed chemical potential $\mu$) ensembles, monitoring variations in temperature T and magnetic field h, show rich phase diagrams in a T-$\mu$ space consisting of pairing fluctuations and signatures of condensation. These electron pairing instabilities are seen when the onsite Coulomb interaction U is smaller than a critical value U$_c$(T) and they point to a possible electron pairing mechanism. The specific heat, magnetization, charge pairing and spin pairing provide strong support for the existence of competing (paired and unpaired) phases near optimal doping in these clusters as observed in recent experiments in doped La$_{2-x}$Sr$_x$CuO$_{4+y}$ high T$_c$ superconductors.Comment: 5 pages, 5 figure