Partial Matrix Techniques.

Partial matrix techniques are those in which gravity models are fitted to a partially observed matrix of trips and journey costs, and used to infer the trips in the unobserved cells. This paper reviews the theoretical basis from which such techniques have been developed, and demonstrates the need to pay careful attention to the - underlying assumptions, which in effect require that the model be a good fit to be observed data (and also a good 'fit' to the unobserved data). Circumstances are described in which the estimates for the unobserved cells may not be uniquely determined, and the effects of data structure on the reliability of the estimates (assuming these to be unique) are discussed. Ways are suggested in which further theoretical and empirical research might demonstrate whether a given pattern of observations would lead to particularly error-prone estimates

How Can Speech Recognisers Help Applied Research in the Civil Engineering, Transport and Related Industries

BACKGROUND Speech recognition technology is rapidly advancing to the point here it can be usefully applied in a wide range of mtexts. For applications within the SERC Environment Committee's area of interest -civil engineering; construction; building; transport; water resources there are a number of kinds of recording situation in which one needs to keep one's eyes on the situation being studied; or in which the recording conditions (eg moving around with instruments) are unfavourable. The limitations of conventional pen and paper recording for these situations are obvious; and the limitations of hand-held data capture devices are also becoming apparent. Speech is therefore an easier medium to use; and a tape recorder a convenient means of recording the observations. For well defined recording tasks; speech recognisers might be a helpful way of transcribing the record. This seminar was convened to enable those who are potentially interested in such an application of information technology to hear of the latest developnents and assessments of the suitability of the technology

Microsimulation of Organised Car Sharing – Model Predications and Policy Implications.

This paper presents the results of a range of tests of organised car sharing schemes. The performance of the schemes is predicted using a sophisticated microsimulation model. A brief resume of the model is followed by a description of the tests and an analysis of their results. Conclusions are drawn on the place of organised car sharing within broader transport policies, the performance of the model when compared to the available empirical data and directions for public research. The tests here presented include: a series of sensitivity analyses; tests of organisational strategies for car sharing schemes; tests of schemes in a variety of locations and at a variety of scales and finally a batch of tests which investigate the effect of major changes in the operating environment of car sharing schemes - changes in the price of fuel and public transport fares and the provision of parking space incentives for car sharers for example

Production of a soluble and functional recombinant apolipoproteinD in the Pichia pastoris expression system

ApolipoproteinD (ApoD) is a human glycoprotein from the lipocalin family. ApoD contains a conserved central motif of an 8-stranded antiparallel β-sheet, which forms a beta-barrel that can be used for transport and storage of diverse hydrophobic ligands. Due to hydrophobic nature of ApoD, it has been difficult to generate a recombinant version of this protein. In the present work, we aimed at the production of ApoD in the robust Pichia pastoris expression system. To this end, the ApoD gene sequence was synthesized and subcloned for expression in the yeast host cells. Following integration of the ApoD gene into the yeast genomic region using homologous recombination, the ApoD recombinant protein was induced using methanol, reaching its maximum induction at 96 h. Having purified the ApoD recombinant protein by affinity chromatography, we measured the dissociation constant (KD) using its natural ligands: progesterone and arachidonic acid. Our results provide a viable solution to the production of recombinant ApoD protein in lieu of previous obstacles in generating soluble and functional ApoD protein. © 2016 Elsevier Inc. All rights reserved

The Internal Validation of a National Model of Long Distance Traffic.

During 1980/81, the Department of Transport developed a model for describing the distribution of private vehicle trips between 642 districts in Great Britain, using data from household and roadside interviews conducted in 1976 for the Regional Highways Traffic Model, and a new formulation of the gravity model, called a composite approach, in which shorter length movements were described at a finer level of zonal detail than longer movements. This report describes the results of an independent validation exercise conducted for the Department, in which the theoretical basis of the model and its the quality of its fit to base year data were examined. The report discusses model specification; input data; calibration issues; and accuracy assessment. The main problems addressed included the treatment of intrazonal and terminal costs, which was thought to be deficient; the trip-end estimates to which the model was constrained, which were shown to have substantial variability and to be biassed (though the cause of the latter could be readily removed), with some evidence of geographical under-specification; and the differences between roadside and household interview estimates. The report includes a detailed examination of the composite model specification and contains suggestions for improving the way in which such models are fitted. The main technical developments, for both theory and practice, are the methods developed for assessing the accuracy of the fitted model and for examining the quality of its fit with respect to the observed data, taking account of the variances and covariances of modelled and data values. Overall, the broad conclusion was that, whilst there appeared to be broad compatibility between modelled and onserved data in observed cells, there was clear evidence of inadequacy in certain respects, such as for example underestimation of intradistr ict trips. This work was done in co-operation with Howard Humphreys and Partners and Transportation Planning Associates, who validated the model against independent external data; their work is reported separately

Serum thyroxin level during the first-trimester of pregnancy

Objective: The aim of this study was to assess the requirement of serum thyroxin levels during the early stage of the first trimester of pregnancy. Methodology: Serum thyroxin levels of 120 apparently healthy women were evaluated in Gorgan in northern Iran during 2007-08 by the enzyme linked immunosorbant assay (ELISA). Results: According to the reference intervals of our standard kit, 48% of the pregnant women in this study had elevated thyroxin levels. Conclusion: The findings of this study can be misleading, because it was based on the laboratory standard kit, women normal range, as general. Pregnant women require higher levels of thyroxin and therefore, a specific normal range for the first trimester of pregnancy should be established in each particular region

Disposition Choices Based on Energy Footprints instead of Recovery Quota

This paper addresses the impact of disposition choices on the energy use of closed-loop supply chains. In a life cycle perspective, energy used in the forward chain which is locked up in the product is recaptured in recovery. High quality recovery replaces virgin production and thereby saves energy. This so called substitution effect is often ignored. Governments worldwide implement Extended Producer Responsibility (EPR). Policies are based on recovery quota and not effective from an energy point of view. This in turn leads to unnecessary emissions of amongst others CO2. This research evaluates current EPR policies and presents six policy alternatives from an energy standpoint. The Pareto-frontier model used is generic and can be applied to other closed loops supply chains under EPR, exploiting the substitution effect. The measures modeled are applied to five WEEE cases. We discuss results, pros an cons of various alternatives and complementary measures that might be taken.extended producer responsibility;disposition;energy perspective;substitution effect;government policies;Pareto efficiency

Charge disproportionation and Jahn-Teller distortion in LiNiO2 and NaNiO2: A density functional theory study

Density functional theory calculations have been performed on three potential ground-state configurations of LiNiO2 and NaNiO2. These calculations show that, whereas NaNiO2 shows the expected cooperative Jahn-Teller distortion (and therefore a crystal structure with C2/m symmetry), LiNiO2 shows at least two possible crystal structures very close in energy (within 3 meV/f.u.): P21/c and P2/c. Moreover, one of them (P2/c) shows charge disproportionation of the (expected) Ni3+ cations into Ni2+ and Ni4+. We discuss the implications of this complex ground state for the interpretation of the available electron and neutron structure data, its electronic and complex magnetic behaviour

Applications of Expert Systems in Transport

BACKGROUND Experienced judgement and specialist knowledge are essential to the proper specification, understanding and interpretation of data and computer analyses. The human expert has traditionally supplied this knowledge and judgement with the computer doing the necessary number-crunching. However, artificial intelligence (AI) research provides ways of embodying this knowledge and judgement within computer programs. Despite an early lead in the field, UK research and developmnent into AI techniques was held back in the 1970s when the then Science Research Council took the view that the 'combinatorial explosion' of possibilities would be an insurmountable obstacle to AI developent. But in America and Japan research continued, and the surge of interest in the 1980s has been a consequence of the 'Fifth Generation Computer' research programme initiated by Japan (Feigenbaum and McCorduck; 1984). This led in Europe to the ESPRIT programme of advanced technology research, and in the UK to the Alvey programme (Department of Industry, 1982). As a result, all sectors of industry have been encouraged to consider how such advanced technology can be applied, and the transport industry is no exception. This paper sets out to explain some of the relevant techniques in simple terms, and to describe a number of situations in which transport planning and operations might be helped through their use, illustrating this by reference to the pioneering work going on in transport applications in the USA, Britain and Australia