Book review

The goal of this study is to extend Rasmussen's framework for risk management to research organisations having to deal with reduced income from government funding and increased market orientation. One human factors research organisation was studied in detail. Using archival records, changes were studied over the period 1989–2010. The results showed an increase in income from market funding relative to government funding, and a decrease in written output. Predictions by stress–strain theory were confirmed in that during the first 5 years of the period under consideration, a linear relationship between the increase in market funding and written output was observed, whereas a nonlinear relationship was observed in the next 5–10 years, indicating a larger decrease in written output than would be expected. Generally, the results show that research organisations are adaptive systems that trade off resource allocation to either commercial activities or scientific activities, depending on incentive schemes.     

A review on carbon nanotube/polymer composites for organic solar cells

Carbon nanotubes (CNTs) have unique properties, such as their electrical conductivity, that enable them to be combined with conducting polymers to form composites for use in organic solar cells (OSCs). It is envisaged that the improved composite has a higher efficiency of green energy and will reduce the cost of these cells. The use of such alternative energy sources also drastically reduces overuse of fossil fuels and consequently limits environmental degradation. This review compares research and performance between conventional silicon solar cells and OSCs. It also discusses OSC photoexcitation and charge carrier generation with the incorporation of CNTs, physicochemical properties of the composites and other factors that affect the efficiencies of OSCs. In addition, properties of CNTs that favour their dispersion in polymer matrices as acceptors and charge carriers to the electrodes are covered. The effects of CNTs containing dopants, such as nitrogen and boron, on charge transfer are discussed. Also, the fabrication techniques of OSCs that include CNT/polymer composite processing and the methods of film deposition on the substrate are described. Finally, the case studies of OSCs containing polymers with single‐walled CNTs, double‐walled CNTs or multi‐walled CNTs are evaluated. Copyright © 2014 John Wiley & Sons, Ltd.     

Enhancing learning outcomes through self-regulated learning support with an Open Learner Model

Open Learner Models (OLMs) have great potential to support students’ Self-Regulated Learning (SRL) in Intelligent Tutoring Systems (ITSs). Yet few classroom experiments have been conducted to empirically evaluate whether and how an OLM can enhance students’ domain level learning outcomes through the scaffolding of SRL processes in an ITS. In two classroom experiments with a total of 302 7th- and 8th-grade students, we investigated the effect of (a) an OLM that supports students’ self-assessment of their equation-solving skills and (b) shared control over problem selection, on students’ equation-solving abilities, enjoyment of learning with the tutor, self-assessment accuracy, and problem selection decisions. In the first, smaller experiment, the hypothesized main effect of the OLM on students’ learning outcomes was confirmed; we found no main effect of shared control of problem selection, nor an interaction. In the second, larger experiment, the hypothesized main effects were not confirmed, but we found an interaction such that the students who had access to the OLM learned significantly better equation-solving skills than their counterparts when shared control over problem selection was offered in the system. Thus, the two experiments support the notion that an OLM can enhance students’ domain-level learning outcomes through scaffolding of SRL processes, and are among the first in-vivo classroom experiments to do so. They suggest that an OLM is especially effective if it is designed to support multiple SRL processes.     

Exact solution of a plastic hollow sphere with a Mises–Schleicher matrix

In this paper we establish the exact solution for a hollow sphere with a rigid-plastic pressure-sensitive matrix and subjected to hydrostatic tension or compression. The matrix is assumed to obey to a parabolic Mises–Schleicher criterion. The closed-form expressions of the velocity field and of the stress field are provided. These exact solutions, expressed by means of the Lambert W function, allow to assess and discuss existing results.     

A Robust Transferable Method for the Determination of Glyphosate Residue in Liver After Derivatization by Ultra-high Pressure Liquid Chromatography–Tandem Mass Spectrometry

Glyphosate determination in liver is challenging due to this particular molecule/matrix combination. Glyphosate is a very polar molecule and liver composition is highly variable between individuals and species. Since 2014, the Multiannual Control Program (MACP) of the European Union (EU) demands to analyse glyphosate in food of animal origin on a voluntary basis. Moreover, this analysis will be mandatory in 2017. This paper describes a robust and easily transferable method for glyphosate quantification in liver of animal origin by means of liquid chromatography–tandem mass spectrometry (LC-MS/MS). An intensive clean-up was used to eliminate matrix interferences and was combined with a derivatization step which ensures good retention of glyphosate on a conventional reverse-phase LC column. This method allows to meet the MACP requirements without a time-consuming change in the set-up of the routinely used LC-MS/MS system. Furthermore, it allows the use of an LC column and mobile phases often used in multi-residue analysis. The analytical method was validated according to the SANCO/12571/2013 criteria. Isotopic dilution was used to quantify glyphosate, leading to mean apparent recoveries of 115 and 101 % for the low (0.025 mg kg^?1) and the high (0.250 mg kg^?1) fortification levels, respectively. At both levels, the relative standard deviation was below 10 %. The limit of quantification of 0.025 mg kg^?1 was found to be satisfactory as it was below the maximum residue level (MRL) value set at 0.050 mg kg^?1 for glyphosate in liver. It is also the lowest MRL for all commodity types.     

Evaluation of Agronomic and Seed Characteristics in Elevated Oleic Acid Soybean Lines in the South-Eastern US

Increasing oleic acid, a monounsaturated fatty acid, is reported to strike the best balance between cold flow properties and oxidative stability in soybean seed oil to enhance biodiesel and produce a better burning fuel. In addition, it is important that elevated oleic acid soybeans have the agronomic traits of local cultivars and maintain oleic acid stability across environments. Research was conducted in 2007–2008 to evaluate six Roundup Ready^® soybean recombinant inbred lines exhibiting enhanced levels of oleic acid. The six elevated oleic lines averaged a 55% increase in oleic acid and a 43% decrease in linolenic acid over the two commercial cultivars (AG3906 and AG4103). Some elevated oleic acid genotypes fulfilled the linear regression definition of a stable genotype. TN03-93RR was the best genotype because of its oleic acid content (397 g kg^?1) and desirable regression estimates for stability. Iodine value (IV), peroxide value (PV), and induction period (IP) were used to evaluate the fuel properties of the two lines with the highest oleic acid content and the two commercial cultivars. The elevated oleic acid lines had significantly better IP, PV and IV for better biodiesel properties and oxidative stability than the two commercial cultivars.     

Improving database performance with a mixed fragmentation design

The performance of database operations can be enhanced with an efficient storage structure design using attribute partitioning and/or tuple clustering. Previous research deals mostly with attribute partitioning. We address here the combined problem of attribute partitioning and tuple clustering. We propose a novel approach for this mixed fragmentation problem by applying a genetic algorithm iteratively to attribute partitioning and tuple clustering sub-problems. We compared our results to attribute-only partitioning and random search solution, resulting in a database access cost reduction of upto 70% and 67% respectively. We analyzed the effect of varying genetic parameters on the optimal solution through experimentation.     

Fault diagnosis based on adaptive observer for a class of non-linear systems with unknown parameters

In this paper, the fault diagnosis problem for a class of non-linear systems with uncertainty which depends on states, inputs and unknown constant parameters is discussed. Under some geometric conditions, the system is transformed into two different subsystems. One is not affected by actuator faults, so a non-linear adaptive observer can be designed based on the assumption of the strictly positive realness (SPR). The other whose states can be measured is affected by the faults. Actuator fault diagnosis is based on estimations of both the state and the unknown parameters with good accuracy. Discussions on release of SPR requirement and extension to the sensor fault case are also made. Finally, two examples are given in order to illustrate the applicability of the proposed methods for actuator fault diagnosis and sensor fault diagnosis respectively.