1,604 research outputs found
Development of techniques to predict production line efficiency
This industrial based research project was undertaken for British Leyland and arose as a result of poor system efficiency on the Maxi and Marina vehicle body build lines. The major factors in the deterioration of system efficiency were identified as: a) The introduction of a 'Gateline' system of vehicle body build. b) The degeneration of a newly introduced measured daywork payment scheme. By relating the conclusions of past work on payment systems to the situation at Cowley, it was concluded that a combination of poor industrial relations and a lack of managerial control had caused the measured daywork scheme to degenerate into a straightforward payment for time at work. This ellminated the monetary incentive to achieve schedule with the consequence that both inefficiency and operating costs increased. To analyse further the cause of inefficiency, a study of Marina gateline stoppage logs was carried out. This revealed that poor system efficiency on the gateline was caused more by the nature of its design than poor reliability on individual items of' plant. The consideration given to system efficiency at the design stage was found to be negligible, the main obstacles being: a) A lack of understanding pertaining to the influence of certain design factors on the efficiency of a production line. b) The absence of data and techniques to predict system efficiency at the design stage. To remedy this situation, a computer simulation study of' the design factors was carried out from which relationships with system efficiency were established and empirical efficiency equations developed. Sets of tables were compiled from the equations and efficiency data relevant to vehicle body building established from the gateline stoppage logs. Computer simulation, the equations and the tables,when used in conjunction. with good efficiency data, are shown to be accurate methods of predicting production line system.efficiency
Can whole-drawer images measure up? A reply to Johnson et al. (2013)?
Johnson et al. (2013) found that morphometric measurements of dragonfly wings taken from actual specimens and measurements taken from whole-drawer images of those specimens were equally accurate. We do not believe that their conclusions are justified by their data and analysis. Our reasons are, first, that their study was constrained in ways that restrict the generalisability of their results, but second, and of far greater significance, their statistical approach was entirely unsuited to their data and their results misled them to erroneous conclusions. We offer an alternative analysis of their data as published. Our reanalysis demonstrates, contra Johnson et al., that measurements from scanned images are not a reliable substitute for direct measurement
Physical Origin of Differences among various Measures of Solar Meridional Circulation
We show that systematic differences between surface Doppler and magnetic
element tracking measures of solar meridional flow can be explained by the
effects of surface turbulent magnetic diffusion. Feature-tracking speeds are
lower than plasma speeds in low and mid-latitudes, because magnetic diffusion
opposes poleward plasma flow in low-latitudes whereas it adds to plasma flow at
high latitudes. Flux transport dynamo models must input plasma flow; the
model-outputs yield estimates of the surface magnetic feature tracking speed.
We demonstrate that the differences between plasma speed and magnetic pattern
speed in a flux-transport dynamo are consistent with the observed difference
between these speeds.Comment: To appear in Ap
Phosphorus and sulphur interactions, 1978.
Yield results, 78AL3, 78KE4, 78M08, 78BY3, 78BA8, 78BU3, 78N04, 78A7, 78C4, 78B4, 78MA2.
Soil sampling data
Locating regional health policy: Institutions, politics, and practices
Poverty reduction and health became central in the agendas of Southern regional organisations in the last two decades. Yet, little is known about how these organisations address poverty, inclusion and social inequality, and how Southern regional formations are engaging in power constellations, institutions, processes, interests and ideological positions within different spheres of governance. This article reviews academic literatures spanning global social policy, regional studies and diplomacy studies, and the state of knowledge and understanding of the ‘place’ of regional actors in health governance as a global political practice therein. It identifies theoretical and thematic points of connection between disparate literatures and how these can be bridged through research focusing on the social policies of regional organisations and regional integration processes. This framework hence locates the contributions of each of the research articles of this Special Issue of Global Social Policy on the regional dimension of health policy and diplomacy in relation to Southern Africa and South America. It also highlights the ways in which the articles bring new evidence about how social relations of welfare are being (re)made over larger scales and how regional actors may initiate new norms to improve health rights in international arenas engaging in new forms of ‘regional’ diplomacy
The cladistics and classification of the Bombyliidae (Diptera: Asiloidea). Bulletin of the AMNH ; no. 219
191 p. : ill. (some col.) ; 26 cm.Includes bibliographical references (p. 165-172)."Previous classifications and phylogenetic trees of the Asiloidea and the Bombyliidae are reviewed. Data from male genital musculature presented by Ovchinnikova (1989) and female genitalia by Muhlenberg (1971b) are reanalyzed within a numerical cladistic framework. A cladogram of the Bombyliidae and their relatives is constructed based on a data matrix containing 87 taxa and 154 characters. This study includes 24 non-Bombyliidae taxa used as outgroups, from the families Rhagionidae, Nemestrinidae, Acroceridae, Asilidae, Therevidae, Apioceridae, Mydidae, Scenopinidae, Hilarimorphidae, and Apsilocephalidae. I chose 63 ingroup species representing all the currently accepted subfamilies and tribes except the Xenoprosopinae and Villoestrini. 147 of the characters used were derived from adult morphology and 7 were from larval morphology. The data set was analyzed using the parsimony program Hennig86 which identified 8 most parsimonious trees, each with a length of 716 steps, consistency index of 0.25, and retention index of 0.71. All characters are described and almost all are illustrated using line drawings, photographs, and scanning electron micrographs. Previously used characters are reanalyzed and new character systems are introduced, especially features of the postcranium and cibarium. The Acroceridae and Nemestrinidae do not form a monophyletic group and each should be recognized at superfamily level. The Asiloidea is also weakly monophyletic, based largely on larval features. The Apioceridae is found not to be monophyletic, some included genera being more closely related to the Mydidae. The Hilarimorphidae, including the proratine Apystomyia Melander, form the sister-group to the Bombyliidae. The remaining Proratinae form a clade with the Scenopinidae, confirming recent work on the subfamily. Bombyliidae, as here defined to exclude genera traditionally placed in the Proratinae, is found to be monophyletic, however the evidence for its monophyly is weak. The subfamily Heterotropinae was found to be nested within the Bombyliidae, thus the free-living, predatory habits of Heterotropus Loew larvae are interpreted as reversals from a parasitoid lifestyle rather than a primary plesiomorphic condition. In a reclassification of the Bombyliidae, 15 subfamilies are recognized: the Mythicomyiinae, Oligodraninae, Usiinae, Toxophorinae, Lordotinae new subfamily, Heterotropinae, Bombyliinae, Crocidiinae new statues, Mariobezziinae, Oniromyiinae, Cythereinae, Lomatiinae, Anthracinae, Tomomyzinae, and Antoniinae. The position of Sericosoma Macquart requires further research; it exhibits closest affinity with the Mariobezziinae. The proposed classification is conservative and reflects much of the structure of previous classifications. Chief differences include the recognition of the Gerontini and Systropodini as tribes of the Toxophorinae rather than separate subfamilies and the synonomy of the Cylleniinae within the Cythereinae. Crocidiinae is recognized as a subfamily, rather than a tribe of the Bombyliinae. Lordotinae is the only new family-level taxon proposed, characterized by the highly modified, telescoping female genitalia which are adapted for inserting the eggs into the substrate. Tribal divisions within the Bombyliinae, Lomatiinae, and Anthracinae are discussed. A key to the subfamilies of Bombyliidae is presented, and all subfamilies are diagnosed, synapomorphies listed, and their taxonomic scope, distribution, and biogeography briefly discussed. The fossil history of the Bombyliidae is discussed in relation to the cladogram. Bombyliidae probably originated in the Jurassic and had undergone much diversification at subfamily level by the end of the Cretaceous. The evolution of the bombyliid postcranium and female sand chamber is discussed in light of the cladogram. The evolution of the acanthophorites within the Bombyliidae is discussed in relation to the occurrence of this feature in other families of Asiloidea"--P. 5
Surface Flux Transport on the Sun
We review the surface flux transport model for the evolution of magnetic flux patterns on the Sun’s surface. Our underlying motivation is to understand the model’s prediction of the polar field (or axial dipole) strength at the end of the solar cycle. The main focus is on the “classical” model: namely, steady axisymmetric profiles for differential rotation and meridional flow, and uniform supergranular diffusion. Nevertheless, the review concentrates on recent advances, notably in understanding the roles of transport parameters and – in particular – the source term. We also discuss the physical justification for the surface flux transport model, along with efforts to incorporate radial diffusion, and conclude by summarizing the main directions where researchers have moved beyond the classical model
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