Modelling by supersaturated designs

The analysis of supersaturated designs is an interesting problem of great importance since it provides economic estimates. Moreover, this problem is challenging due to the fact that the design matrix has a complicated structure. The identification of the active factors in supersaturated designs is investigated. The singular value decomposition (SVD), principal components analysis and regression analysis are used together in an SVD principal regression method to reveal the hidden true linear model. Special cases are studied by using simulation data under idealized conditions. Simulations are used to investigate the performance of the method and also to compare the proposed method with other known methods from the literature.     

Agglomeration problems during fluidized bed gasification of olive-oil residue: evaluation of fractionation and leaching as pre-treatments

The effect of two pre-treatment techniques leaching and fractionation on the agglomeration problems observed during the gasification of the olive-oil residue material in a fluidized bed reactor was studied. The obtained results proved to be very positive in the case of leaching showing a substantial decrease of the agglomeration phenomena in the bed during the gasification tests compared with the results from the tests with the un-treated material. On the other hand, fractionation appeared to increase the ash reactivity leading to a dramatic increase of the agglomeration problems during the gasification process.     

Monitoring the coefficient of variation using a variable sample size control chart

This paper proposes an adaptive Shewhart control chart implementing a variable sample size strategy in order to monitor the coefficient of variation. The goals of this paper are as follows: (a) to propose an easy-to-use 3-parameter logarithmic transformation for the coefficient of variation in order to handle the variable sample size aspect; (b) to derive the formulas for computing the average run length, the standard deviation run length, and the average sample size and to evaluate the performance of the proposed chart based on these criteria; (c) to present ready-to-use tables with optimal chart parameters minimizing the out-of-control average run length as well as the out-of-control average sample size; and (d) to compare this chart with the fixed sampling rate, variable sampling interval, and synthetic control charts. An example illustrates the use of the variable sample size control chart on real data gathered from a casting process.     

Study of organic acids, volatile fraction and caseins of a new Halloumi-type cheese during ripening in whey brine

Organic acids, fat hydrolysis, volatile compounds and sensory characteristics of a new brine cheese which combines characteristics of Halloumi and Feta cheeses during its ripening in whey brine (100g NaCl L⁻¹) were studied. Thermotolerant protease of Mucor miehei as a coagulant enzyme and a mixture of thermotolerant starter cultures Enterococcus faecium 0165 (0.5% w/w) and Lactobacillus casei 80 10D were used. Good quality new Halloumi-type cheese was produced with higher proteolysis than traditional Halloumi cheese kept in whey brine. The volatile compounds identified comprised alcohols, aldehydes, ketones, acids, esters, hydrocarbons and sulphur compounds. Ethanol was the dominant volatile compound determined. Lactic acid was the dominant acid produced; its concentration increased during ripening, reaching a maximum value of 9929 mg kg⁻¹ at day 30. Acetic acid was also found in high amounts, which increased during cheese ripening. Lipolysis of cheese was not intense. The most abundant acids of the mature cheese were palmitic, oleic and acetic acid. The Halloumi-type cheese scored higher in the sensory analysis when fresh than did the mature cheese.     

Impacts of biodiesel production on Croatian economy

The aim of this paper is to assess the direct and indirect impacts on a national economy from biodiesel (rapeseed methyl ester (RME)) production using input–output (I–O) analysis. Biodiesel development in Croatia is used as a case study. For Croatia, as for many other countries in Europe, biodiesel is a new activity not included in the existing I–O sectoral accounts. For this reason the I–O table has to be modified accordingly before being able to quantify the effect of an exogenous demand for biodiesel. Impacts in terms of output, income and employment lead to the conclusion that biodiesel production could have significant positive net impact on the Croatian economy despite the high level of subsidies for rapeseed growing.     

Optically Active Spherical Polyelectrolyte Brushes with a Nanocrystalline Magnetic Core

The unique properties of magnetic nanocrystals have triggered intensive research towards their effective functionalization and application in many technological fields. Although synthesis of magnetic colloids is being thoroughly studied, there is limited knowledge on the synthesis, characterization, and properties of magnetic polyelectrolyte spherical brushes. In the present work, the preparation of such hybrids and the subsequent formation of stable aqueous colloids are described. The core of the spherical brush consists of a magnetic γ‐Fe₂O₃ nanocrystallite (faceted but mostly spherical‐like) with a mean diameter of 17 nm. The bioadhesive polyelectrolyte poly(sodium 4‐styrene sulfonate), forming the surrounding brush layer, was proven to be an effective covalently modifying macromolecule for the iron oxide surface, as Fourier transform IR spectroscopy revealed. Several observations on colloidal aspects are discussed and are successfully explained by models and experiments describing polyelectrolyte brushes with a soft polymeric core. Finally, the hybrids exhibit their multifunctional character and their technological importance by combining in a single and soluble product with magnetic and nonlinear optical properties.     

Delivering a lifelong integrated electronic health record based on a service oriented architecture.

Efficient access to a citizen's Integrated Electronic Health Record (I-EHR) is considered to be the cornerstone for the support of continuity of care, the reduction of avoidable mistakes, and the provision of tools and methods to support evidence-based medicine. For the past several years, a number of applications and services (including a lifelong I-EHR) have been installed, and enterprise and regional infrastructure has been developed, in HYGEIAnet, the Regional Health Information Network (RHIN) of the island of Crete, Greece. Through this paper, the technological effort toward the delivery of a lifelong I-EHR by means of World Wide Web Consortium (W3C) technologies, on top of a service-oriented architecture that reuses already existing middleware components is presented and critical issues are discussed. Certain design and development decisions are exposed and explained, laying this way the ground for coordinated, dynamic navigation to personalized healthcare delivery.     

Environmental cost-effectiveness of bio diesel production in Greece: Current policies and alternative scenarios

Following European Directive 2003/30/EC, the Greek Government adapted legislation that introduces and regulates the bio diesel market. The implemented quota scheme allocates the country's annual, predetermined, tax exempt production of bio diesel to industries based on their ability to meet several criteria. A number of bio diesel supply chain stakeholders have criticized this policy for being efficiency-robbing and vague. This paper uses 2007 data from energy crop farms and three bio diesel-producing companies in order to assess these criticisms. We study the economic and environmental aspects of the currently adopted policy and compare them to three alternative scenarios. We conclude that such criticisms have a merit and that policy makers need to reconsider their alternative options regarding the promotion of bio diesel in transport. Permission of sales directly to local consumers and promotion of forward integration by farmers are efficiency enhancing and environment-friendly means of promoting the use of bio diesel in transport.