Information channel diagrams: an approach for modelling information flows

In this article, the ‘information channel diagram’ (ICD) approach is introduced as a diagrammatical tool for modelling information flow during the delivery phase of organisations in which goods are deployed or delivered to customers. An initial review and evaluation of current tools for modelling information flow will be conducted based on the characteristics of information flow during the delivery phases in organisations. Diagrammatic primitives and a prescribed modelling methodology for developing an ICD will be presented, and a case scenario of the delivery phase of an organisation within the health care sector will be applied to demonstrate the use of the ICD. The article concludes by discussing some applications, generalisation potential and limitations of the ICD approach.     

Inverted polymer solar cells with a solution-processed cesium halide interlayer

We demonstrate the utility of a low-cost cesium iodide interlayer spun from an aqueous or 2-ethoxyethanol solution on ITO in inverted polymer solar cells of the structure ITO/CsI/P3HT:PCBM/MoO₃/Al, where P3HT is poly(3-hexylthiophene) and PCBM is [6,6]-phenyl-C₆₀-butyric acid methyl ester. The power conversion efficiency (PCE) of optimized cells was ～3.4%, comparable to that we obtained for inverted cells with Cs carbonate. The thickness of the CsI film was adjusted by varying the solution concentration. The concentration affected the surface morphology of P3HT:PCBM and the density of fractal-like aggregates (possibly related to the presence of Cs and film fabrication conditions) formed near the anode, as revealed by scanning electron microscopy. Auger analysis indicated a P3HT-rich surface. Optimization of the cells was achieved also by varying the thickness of the MoO₃ and the drying/annealing conditions of the active layer, as was evident from the current–voltage characteristics, external quantum efficiency spectra, and PCE. The cells with the CsI interlayer were compared additionally to cells with CsCl or CsF interlayers (with a PCE of up to ～2.7%), which were inferior to the comparable cells with Cs₂CO₃ or CsI. The surface concentrations of Cs and the halide on ITO were monitored using X-ray photoelectron spectroscopy. The iodine level was low with the Cs:I ratio exceeding 8:1. In contrast, the Cs:Cl ratio was ～1.4:1 and the Cs:F ratio was ～1:1; the Cs₂CO₃ decomposed partially, as expected. Therefore, for CsI, as is the case for Cs₂CO₃ but not for CsF, Cs–O bonds are formed at the surface. Such bonds on ITO are important in modifying the ITO work function, improving the cell performance. The results indicate that spin coating solutions of the high polarity CsI is a promising and easy approach to introduce Cs–O on ITO in inverted structures for increased electron extraction from PCBM and possibly hole extraction from the P3HT-rich surface at the anode.     

Efficient driver drowsiness detection at moderate levels of drowsiness

Previous research on driver drowsiness detection has focused primarily on lane deviation metrics and high levels of fatigue. The present research sought to develop a method for detecting driver drowsiness at more moderate levels of fatigue, well before accident risk is imminent. Eighty-seven different driver drowsiness detection metrics proposed in the literature were evaluated in two simulated shift work studies with high-fidelity simulator driving in a controlled laboratory environment. Twenty-nine participants were subjected to a night shift condition, which resulted in moderate levels of fatigue; 12 participants were in a day shift condition, which served as control. Ten simulated work days in the study design each included four 30-min driving sessions, during which participants drove a standardized scenario of rural highways. Ten straight and uneventful road segments in each driving session were designated to extract the 87 different driving metrics being evaluated. The dimensionality of the overall data set across all participants, all driving sessions and all road segments was reduced with principal component analysis, which revealed that there were two dominant dimensions: measures of steering wheel variability and measures of lateral lane position variability. The latter correlated most with an independent measure of fatigue, namely performance on a psychomotor vigilance test administered prior to each drive. We replicated our findings across eight curved road segments used for validation in each driving session. Furthermore, we showed that lateral lane position variability could be derived from measured changes in steering wheel angle through a transfer function, reflecting how steering wheel movements change vehicle heading in accordance with the forces acting on the vehicle and the road. This is important given that traditional video-based lane tracking technology is prone to data loss when lane markers are missing, when weather conditions are bad, or in darkness. Our research findings indicated that steering wheel variability provides a basis for developing a cost-effective and easy-to-install alternative technology for in-vehicle driver drowsiness detection at moderate levels of fatigue.     

Liquid Chromatography–Hybrid Linear Ion Trap–High-Resolution Mass Spectrometry (LTQ-Orbitrap) Method for the Determination of Glycoalkaloids and Their Aglycons in Potato Samples

Potatoes produce biologically active secondary metabolites like glycoalkaloids and their aglycons, which may have both adverse and beneficial effects in the diet. A new analytical method that uses liquid chromatography–mass spectrometry (LTQ-Orbitrap) has been developed for the analysis of glycoalkaloids and their aglycons in potato samples. Two glycoalkaloids, α-solanine and α-chaconine, and two aglycons, demissidine and solasodine, were quantified in potato samples. Samples were extracted using methanol, purified on an SPE Strata C₁₈ cartridge, and then analyzed in HPLC–mass spectrometry (LTQ-Orbitrap) with the FTMS operating in full scan at a resolving power of 30,000 (FWHM), enabling the detection and accurate mass measurement and with the ITMS mode operating in MRM (multiple reaction monitoring) for glycoalkaloids and their aglycons using the [M + H]⁺ ions and their optimized collision energies. After validation, the method was applied to screen different type of potatoes, and some cooking experiment were conducted.     

Look-Ahead and One-Person Games

Abstract

A preliminary investigation of the role of look-ahead in one-person games is presented. The use of look-ahead in comparing the effectiveness of different heuristic functions is discussed. There is a survey of recent work in tree-searching including that of Doran and Michie [4], Hart, Nilsson, and Raphael [7] and Pohl [17]–[19]. Based on some of Pohl's results, two theorems are proven in Section 2. These suggest a possible use for look-ahead. Some experimental results are presented in Section 3 which satisfy to a limited degree the aforementioned theorems, and some additional observations are made. In conclusion, an attempt is presented to relate look-ahead to the notion of “informedness” introduced by Hart, Nilsson, and Raphael. Finally, some further directions for research are suggested.