Point-wise confidence interval estimation by neural networks: A comparative study based on automotive engine calibration.

In developing neural network techniques for real world applications it is still very rare to see estimates of confidence placed on the neural network predictions. This is a major deficiency, especially in safety-critical systems. In this paper we explore three distinct methods of producing point-wise confidence intervals using neural networks. We compare and contrast Bayesian, Gaussian Process and Predictive error bars evaluated on real data. The problem domain is concerned with the calibration of a real automotive engine management system for both air-fuel ratio determination and on-line ignition timing. This problem requires real-time control and is a good candidate for exploring the use of confidence predictions due to its safety-critical nature.

Retromer controls epithelial cell polarity by trafficking the apical determinant crumbs

The evolutionarily conserved apical determinant Crumbs (Crb) is essential for maintaining apicobasal polarity and integrity of many epithelial tissues [1]. Crb levels are crucial for cell polarity and homeostasis, yet strikingly little is known about its trafficking or the mechanism of its apical localization. Using a newly established, liposome-based system described here, we determined Crb to be an interaction partner and cargo of the retromer complex. Retromer is essential for the retrograde transport of numerous transmembrane proteins from endosomes to the trans-Golgi network (TGN) and is conserved between plants, fungi, and animals [2]. We show that loss of retromer function results in a substantial reduction of Crb in Drosophila larvae, wing discs, and the follicle epithelium. Moreover, loss of retromer phenocopies loss of crb by preventing apical localization of key polarity molecules, such as atypical protein kinase C (aPKC) and Par6 in the follicular epithelium, an effect that can be rescued by overexpression of Crb. Additionally, loss of retromer results in multilayering of the follicular epithelium, indicating that epithelial integrity is severely compromised. Our data reveal a mechanism for Crb trafficking by retromer that is vital for maintaining Crb levels and localization. We also show a novel function for retromer in maintaining epithelial cell polarity.

Supplier competitive advantage in inter-firm business relationships:is Keiretsu really a source of competitive advantage for Japanese automotive suppliers?

This paper explores how firms create and sustain competitive advantage in the inter-firm business relationships from a supplier’s perspective. Ultimately, this paper draws its attention to keiretsu partnerships and how it is perceived by Japanese automotive suppliers. Four main theoretical perspectives (resource based view, industrial organisation, transaction cost economics, and relational network) were considered when developing a conceptual framework based on competitive capability, market diversification, and level of engagement. The framework was examined against two best-practice automotive component suppliers. Later, primary data was also gathered through an interview with a CEO and a survey questionnaire with 11 Japanese companies. As a result, this paper classified these 11 companies into four supplier groups based on tier level (1 and 2) and affiliation condition. Findings propose that there may be little benefit in being an affiliated tier 1 supplier, and that independent tier 2 suppliers may be more competitive than affiliated ones.

The importance of collaborative frontloading in automotive supply networks

Purpose – The purpose of this paper is to investigate how research and development (R&D) collaboration takes place for complex new products in the automotive sector. The research aims to give guidelines to increase the effectiveness of such collaborations. Design/methodology/approach – The methodology used to investigate this issue was grounded theory. The empirical data were collected through a mixture of interviews and questionnaires. The resulting inducted conceptual models were subsequently validated in industrial workshops. Findings – The findings show that frontloading of the collaborative members was a major issue in managing successful R&D collaborations. Research limitations/implications – The limitation of this research is that it is only based in the German automotive industry. Practical implications – Practical implications have come out of this research. Models and guidelines are given to help make a success of collaborative projects and their potential impacts on time, cost and quality metrics. Originality/value – Frontloading is not often studied in a collaborative manner; it is normally studied within just one organisation. This study has novel value because it has involved a number of different members throughout the supplier network.

Assessing the financial impact of 6-Sigma in an automotive company

This paper reports on an assessment of an ongoing 6-Sigma program conducted within a UK based (US owned) automotive company. It gives an overview of the management of the 6-sigma programme and the 23 in-house methodology used. The analysis given in the paper pays particular focus to the financial impacts that individual projects have had. Three projects are chosen from the hundreds that have been completed and are discussed in detail, including which specific techniques have been used and how financially successful the projects were. Commentary is also given on the effectiveness of the overall program along with a critique of how the implementation of 6-Sigma could be more effectively managed in the future. This discussion particularly focuses upon issues such as: project selection and scoping, financial evaluation and data availability, organisational awareness, commitment and involvement, middle management support, functional variation, and maintaining momentum during the rollout of a lengthy program.

Designing and managing collaborative enterprises in the automotive industry

This paper presents the findings of a recently completed research project. It sheds light upon the appropriate governance of inter-firm relationships, in order to achieve competitive success for the whole partnership and its individual members. An exploratory study in the German automotive industry using inductive Grounded Theory was conducted, in order to form a set of propositions that were then validated. The research has resulted in the consolidation of these propositions into a novel concept termed Collaborative Enterprise Governance, which draws on an inter-disciplinary body of knowledge. The core of the concept is a competence based contingency framework that helps enterprise managers in selecting the most appropriate governance strategy (i.e. enterprise structure) for an inter-firm relationships within automotive supply networks (i.e. enterprises), depending on various exogenous and endogenous factors.

Alcohols and other oxygenates in automotive fuels

The aim of this research was to assess the effect of oxygenated hydrocarbons on the knocking characteristics of an engine when blended with low-leaded gasoline. Alcohols, ethers, esters and ketones were tested individually and in various combinations up to an oxygen content of 4% wt/wt in a blend with Series F-7 gasoline of 90, 92, 94 and 96 RON. Tests were carried out at wide open throttle, constant speed and standard timing setting. Engine speed was varied using a dynamometer and knock was detected by two piezoelectric transducers, one on the cylinder head monitoring all four cylinders and one monitoring the cylinder most prone to knock. The engine speeds associated with trace and light knock of a continuous nature were noted. Curves were produced for each oxygenate blend of base RON used against engine speed for the two knock conditions which were compared with those produced using pure Series F-7 fuels. From this a suggested RON of the blend was derived. RON increase was less when using a higher RON base fuel in the blend. Most individual oxygenates showed similar effects in similar concentrations when their oxygen content was comparable. Blends containing more than one oxygenate showed some variation with methanol/MTBE/3 methylbutan-2-one and methanol/MTBE/4 methyl pentan-2-one knocking less than expected and methanol/MTBE/TBA also showing good knock resistance. Further tests to optimise initial findings suggested a blend of methanol and MTBE to be superior although partial replacement of MTBE by 4 methyl pentan-2-one resulted in a fuel of comparable performance. Exhaust emissions were tested for a number of oxygenated blends in 2-star gasoline. 2-star and 4-star fuels were also tested for reference. All oxygenate blends reduced carbon monoxide emissions as expected and hydrocarbon emissions were also reduced. The largest reduction in carbon monoxide occurred using a 14.5 % (1 : 1 : 1) methanol/MTBE/4 methyl pentan-2-one blend. Hydrocarbon emissions were most markedly reduced by a blend containing 25.5 % 4 methyl pentan-2-one. Power output was tested for the blends and indicated a maximum increase of about 5 % at low engine speeds. The most advantageous blends were methanol/4 methyl pentan-2-one (6 : 5) 11% in 2-star and methanol/MTBE/4 methyl pentan-2-one (6 : 3 : 2) 11% in 2-star. In conclusion methanol/MTBE (6 : 5) and (5 : 5), and various combinations of methanol/MTBE/4 methyl pentan-2-one, notably (6 : 3 : 2) gave good results in all tests conducted. CFR testing of these blends showed them to increase both RON and MON substantially.

Associative knowledge controls deployment of visual selective attention

According to some models of visual selective attention, objects in a scene activate corresponding neural representations, which compete for perceptual awareness and motor behavior. During a visual search for a target object, top-down control exerted by working memory representations of the target's defining properties resolves competition in favor of the target. These models, however, ignore the existence of associative links among object representations. Here we show that such associations can strongly influence deployment of attention in humans. In the context of visual search, objects associated with the target were both recalled more often and recognized more accurately than unrelated distractors. Notably, both target and associated objects competitively weakened recognition of unrelated distractors and slowed responses to a luminance probe. Moreover, in a speeded search protocol, associated objects rendered search both slower and less accurate. Finally, the first saccades after onset of the stimulus array were more often directed toward associated than control items.

Exchange controls and European stock market integration

This paper examines the impact on stock price predictability that the removal of exchange controls had on major European countries during the late 1970s and 1980s. It is found that for Germany, Switzerland and France, the removal of exchange controls led to an increase in the interdependence between these and other markets. In contrast, there is little evidence of an increase in interdependence for the UK and Italy.

Exchange controls and the transmission of equity market volatility:the case of the UK

The paper investigates the impact that the relaxation of UK exchange controls in October 1979, had on the transmission of equity market volatility from the UK to other major equity markets. It is suggested that the existence of exchange controls in the UK was an important source of market segmentation which disturbed the transmission of shocks from one country to another, even when shocks contained global information. It is found that when a spillover GARCH(1,1) model is estimated for the five years before and after the removal of exchange controls, volatility shocks spill over from the UK to other markets much more strongly after the removal of exchange controls. This appears to suggest that volatility as well as returns have become more closely related since the UK removed exchange controls.

Documentation of antibiotic prescribing controls in UK NHS hospitals

Objectives: To identify the types, prevalence and nature of antibiotic prescribing control documents within NHS hospitals in the UK. Methods: A self-completion postal questionnaire was sent to each Chief Pharmacist at 465 NHS hospitals in 2001/2002. This contained questions covering hospital demographics, and hospital antibiotic prescribing control documentation, including format, dissemination, approval and review processes. Results: In total, 253 (54%) completed questionnaires were returned. Of these, 168 respondents' hospitals had an antibiotic formulary, 107 had a policy for antibiotic prescribing and 216 had guidelines on antibiotic use. All three types of antibiotic prescribing documents were used by 82 hospitals but 18 did not have any documents; 44% of formularies, 45% of policies and 35% of guidelines were available electronically. The Drug and Therapeutics Committee was the most frequently cited body for document approval and approximately one-third of documents had been approved during the current year of the questionnaire. Only about one-half of responding hospitals had an annual review of documents. Conclusions: Despite publication of high-profile national guidance in response to growing concerns regarding antimicrobial resistance, there has been little increase in the use of antibiotic prescribing control documents in NHS hospitals over the past decade. It is clear that appropriate controls for antibiotic prescribing are not yet universally applied in the UK and recommendations for action have been proposed. © The British Society for Antimicrobial Chemotherapy 2004; all rights reserved.

A post-structural analysis of perceptions and experiences of continuity and change within the UK automotive supplier base

Firms acting as suppliers to the British automotive industry have a long history of so doing, with some evidencing histories that predate even the invention of the motor car. In exploring the challenges faced by the descendants of these firms in the 1990s, a review is undertaken of the bodies of literature surrounding the changes wrought through the increased globalisation of the industry; the impact of new manufacturing technologies and techniques; the rising levels of co-operation between firms; and the growing impact of the automotive 'service sector'. Moreover, an exploration is undertaken of the perceived 'realities' of the automotive industry as constructed through discourse, including the ways in which discourse effects a continual reinterpretation and re-evaluation of the historical evolution of the industry. Attention is focused on the implications of the above for the automotive supply chain, and the means for its rationalisation proposed by the major car manufacturers and their partner-suppliers. Post-structuralist approaches are introduced as part of an attempt to establish and appropriate research methodology that can explore and deconstruct the discourses surrounding 'modernity', 'supply chain rationalisation', 'flexible specialisation' and 'globalisation' within the automotive industry. Analytical research is conducted into the small- to medium-sized business that constitute the majority of the supplier base in the United Kingdom, and the findings of this research are compared with those of a similar study conducted a quarter-century ago. In this way, the relationships of these firms with their customers, suppliers, and peers are investigated, as are their perceptions of a changing marketplace and their reactions to the impact of policies such as the 'supply chain rationalisation' pursued by the major automotive manufacturers. Authoritative discourses of industry form, function, and structure are challenged, with voice being granted to the marginalised: small suppliers, 'service sector' firms, or those only partly involved in the automotive industry.