Comparing whole-link travel time models used in DTA

In a model commonly used in dynamic traffic assignment the link travel time for a vehicle entering a link at time t is taken as a function of the number of vehicles on the link at time t. In an alternative recently introduced model, the travel time for a vehicle entering a link at time t is taken as a function of an estimate of the flow in the immediate neighbourhood of the vehicle, averaged over the time the vehicle is traversing the link. Here we compare the solutions obtained from these two models when applied to various inflow profiles. We also divide the link into segments, apply each model sequentially to the segments and again compare the results. As the number of segments is increased, the discretisation refined to the continuous limit, the solutions from the two models converge to the same solution, which is the solution of the Lighthill, Whitham, Richards (LWR) model for traffic flow. We illustrate the results for different travel time functions and patterns of inflows to the link. In the numerical examples the solutions from the second of the two models are closer to the limit solutions. We also show that the models converge even when the link segments are not homogeneous, and introduce a correction scheme in the second model to compensate for an approximation error, hence improving the approximation to the LWR model.

Comparison of two construction algorithms for local model networks

The divide-and-conquer approach of local model (LM) networks is a common engineering approach to the identification of a complex nonlinear dynamical system. The global representation is obtained from the weighted sum of locally valid, simpler sub-models defined over small regions of the operating space. Constructing such networks requires the determination of appropriate partitioning and the parameters of the LMs. This paper focuses on the structural aspect of LM networks. It compares the computational requirements and performances of the Johansen and Foss (J&F) and LOLIMOT tree-construction algorithms. Several useful and important modifications to each algorithm are proposed. The modelling performances are evaluated using real data from a pilot plant of a pH neutralization process. Results show that while J&F achieves a more accurate nonlinear representation of the pH process, LOLIMOT requires significantly less computational effort.

Trans Governmentality: the production and regulation of gendered subjectivities

Feminist theorists have long critiqued the hierarchical gender division inherent in Western societies, with the inequalities resulting from this divide being widely decried and some progress made in reducing these. Despite increased efforts to theorise trans identification in recent times, gender is still largely understood, both culturally and theoretically, as adhering to the dualism of male/female. I argue within this paper that consideration of the narratives of transpeople and their partners could expand our conceptualisation of gender and offers possible points of resistance from which to challenge the gender binary, thereby destabilising hegemonic discourses of gender. As such I explore the narratives of transpeople and their partners in relation to the construction and reconstruction of gendered subjectivities. Transpeople’s intimate partnerships, considered here due to the critique of gender norms often evident within them, are examined through the theoretical lens of Foucault’s notion of governmentality. This paper offers an example of how governmentality can be a useful tool in the effort to understand gender regulation, not least for those apparently on the margins of ‘normality’.

Non-stationary variogram models for geostatistical sampling optimisation: An empirical investigation using elevation data

A problem with use of the geostatistical Kriging error for optimal sampling design is that the design does not adapt locally to the character of spatial variation. This is because a stationary variogram or covariance function is a parameter of the geostatistical model. The objective of this paper was to investigate the utility of non-stationary geostatistics for optimal sampling design. First, a contour data set of Wiltshire was split into 25 equal sub-regions and a local variogram was predicted for each. These variograms were fitted with models and the coefficients used in Kriging to select optimal sample spacings for each sub-region. Large differences existed between the designs for the whole region (based on the global variogram) and for the sub-regions (based on the local variograms). Second, a segmentation approach was used to divide a digital terrain model into separate segments. Segment-based variograms were predicted and fitted with models. Optimal sample spacings were then determined for the whole region and for the sub-regions. It was demonstrated that the global design was inadequate, grossly over-sampling some segments while under-sampling others.

‘Glimpses into the unmentionable: Montserrat, tourism and anthropological readings of “subordinate exotic” and “comic exotic” travel writing’

This article explores the relationship between anthropology and identity through the process of travel writing and reading. Specifically, the article examines a range of travel writing about the British Caribbean colony Montserrat to read into the culture of the writer. These deconstructive ‘glimpses into the unmentionable’ reveal an implicit racism. The travel writing texts are also found to divide into two types of representation – the ‘subordinate exotic’ and the ‘comic exotic’.

Horowitz’s Theory of Ethnic Party Competition and the Case of the SDLP, 1970-79

Donald Horowitz's theory of ethnic conflict suggests that a political party operating in a deeply divided society can be effected by a centrifugal pull even when it is not subject to formal electoral competition. This idea can be applied to Northern Ireland's SDLP in the 1970s, when the party faced no credible electoral rival within its primary political constituency. Doing so helps to explain why the SDLP failed in its original objective of mobilizing a cross-community constituency, and instead became what Horowitz terms an “ethnically based party,” representing the interests of only one side of the political divide in Northern Ireland.

Vegetation and climate c. 12 300-9000 cal. yr BP at Andoya, NW Norway

Owing to proximity of the North Atlantic Stream and the shelf, the And circle divide ya biota are assumed to have responded rapidly to climatic changes taking place after the Weichselian glaciation. Palynological, macrofossil, loss-on-ignition, tephra and C-14 data from three sites at the northern part of the island of And circle divide ya were studied. The period 12 300-11 950 cal. yr BP was characterized by polar desert vegetation, and 11 950-11 050 cal. yr BP by a moisture-demanding predominantly low-arctic Oxyria vegetation. During the period 11 050-10 650 cal. yr BP, there was a climatic amelioration towards a sub-arctic climate and heaths dominated by Empetrum. After 10 650 cal. yr BP the Oxyria vegetation disappeared. As early as about 10 800 cal. yr BP the bryozoan Cristatella mucedo indicated a climate sufficient for Betula woodland. However, tree birch did not establish until 10 420-10 250 cal. yr BP, indicating a time-lag for the formation of Betula ecotypes adapted to the oceanic climate of And circle divide ya. From about 10 150 to 9400 cal. yr BP the summers were dry and warm. There was a change towards moister, though comparatively warm, climatic conditions about 9400 cal. yr BP. The present data are compared with evidence from marine sediments and the deglaciation history in the region. It is suggested that during most of the period 11 500-10 250 cal. yr BP a similar situation as in present southern Greenland existed, with birch woodland in the inner fjords near the ice sheet and low-arctic heath vegetation along the outer coast.

Culture and the Irish Border:Spaces for Conflict Transformation

The Irish border has been described as a ‘natural’ cultural divide between the island's two dominant indigenous ethno-national communities. However, an examination of key resources of ethno-national group culture - religion, sport and language - provides evidence to challenge this representation. Moreover, in the post-1994 period of conflict transformation, evidence is also presented to support the proposition that the Irish border region has developed into a cultural space in which Irish nationalist and Ulster unionist ethno-national communities can explore cultural differences and commonalities through cross-border, cross-community contact and communication in small group encounters. This space underpins the reconfiguration of the border from barrier to political bridge between North and South. European Union (EU) Peace programmes for Ireland, beginning in 1995, provided the support for a cross-border approach to escaping the cage of ethno-national conflict in Northern Ireland. However, post-2004 EU enlargement signalled the beginning of the end for EU Peace funding and severe economic recession has undermined the expectation of British-Irish intergovernmental intervention to support cross-border partnerships and their work. Therefore, the outlook for the sustainability of this cross-border cultural space is gloomy with potentially deleterious consequences for the continued reconfiguration of the border from barrier to bridge.

Recent Advances in Antidiabetic Drug Therapies Targeting the Enteroinsular Axis

The enteroinsular axis (EIA) constitutes a physiological signalling system whereby intestinal endocrine cells secrete incretin hormones following feeding that potentiate insulin secretion and contribute to the regulation of blood glucose homeostasis. The two key hormones responsible are named glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Recent years have witnessed sustained development of antidiabetic therapies that exploit the EIA. Current clinical compounds divide neatly into two classes. One concerns analogues or mimetics of GLP-1, such as exenatide (Byetta) or liraglutide (NN2211). The other group comprises the gliptins (e. g. sitagliptin and vildagliptin) which boost endogenous incretin activity by inhibiting the enzyme dipeptidyl peptidase 4 (DPP 4) that degrades both GLP-1 and GIP. Ongoing research indicates that further incretin and gliptin compounds will become available for clinical use in the near future, offering comparable or improved efficacy. For incretin analogues there is the prospect of prolonged duration of action and alternative routes of administration. This review focuses on recent advances in pre-clinical research and their translation into clinical studies to provide future therapies for type 2 diabetes targeting the EIA.

The vegetation and climate history of the last glacial cycle in a new pollen record from Lake Fimon (southern Alpine foreland, N-Italy)

The sediments of Like Fimon N Italy contain the first continuous archive of the Late Pleistocene environmental and climate history of the southern Alpine foreland We present here the detailed palynological record of the interval between Termination II and the List Glacial Maximum The age-depth model is obtained by radiocarbon dating in the uppermost part of the record Downward we con elated major forest expansion and contraction events to isotopic events in the Greenland Ice core records via a stepping-stone approach involving intermediate correlation to isotopic events dated by TIMS U/Th in Alpine and Apennine stalagmites and to pollen records from mime cores of the Iberian margin Modelled ages obtained by Bayesian analysis of deposition are thoroughly consistent with actual ages with maximum offset of +/- 1700 years Sharp expansion of broad-leaved temperate forest and of sudden water table rise mark the onset of the Last Interglacial after a treeless steppe phase at the end of penultimate glaciation This event is actually a two-step process which matches the two step rise observed in the isotopic record of the nearby Antro del Corchia stalagmite respectively dated to 132 5 +/- 2 5 and 129 +/- 1 5 ka At the interglacial decline mixed oak forests were replaced by oceanic mixed forests the latter persisting further for 7 ka till the end of the Eemian succession Warm-temperate woody species are still abundant at the Eemian end corroborating a steep gradient between central Europe and the Alpine divide at the inception of the last glacial After a stadial phase marked by moderate forest decline a new expansion of warm broad leaved forests interrupted by minor events and followed by mixed oceanic forests can be identified with the north-alpine Saint Germain I The spread of beech during the oceanic phase is a valuable circumalpine marker The subsequent stadial-interstadial succession lacking the telocratic oceanic phase is also consistent with the evidence at the north alpine foreland The Middle Wurmian (full glacial) is marked by persistence of mixed forests dominated by conifers but with significant lime and other broad leaved species A major Arboreal Pollen decrease is observed at modelled age of 38 7 +/- 0 5 ka (larch expansion and last occurrence of lime) which his been related to Heinrich Event 4 The evidence of afforestation persisting south of the Alps throughout most of MIS 3 contrasts with a boreal and continental landscape known for the northern alpine foreland pointing to a sharp rainfall boundary at the Alpine divide and to southern air circulation This is in agreement with the Alpine paleoglaciological record and is supported by the pressure and rainfall patterns designed by mesoscale paleoclimate simulations Strenghtening the continental high pressure during the full glacial triggered cyclogenesis in the middle latitude eastern Europe and orographic rainfall in the eastern Alps and the Balkanic mountains thus allowing forests development at current sea level altitudes (C) 2010 Elsevier Ltd All rights reserved

Towards a better understanding of the nature and contribution of the interflow to catchment dynamics.

A detailed understanding of flow and contaminant transfer along each of the key hydrological pathways within a catchment is critical for designing and implementing cost effective Programmes of Measures under the Water
Framework Directive.
The Contaminant Movement along Pathways Project (’The Pathways Project’) is an Irish, EPA STRIVE funded, large multi-disciplinary project which is focussed on understanding and modelling flow and attenuation along each of these pathways for the purposes of developing a catchment management tool. The tool will be used by EPA and RBD catchment managers to assess and manage the impacts of diffuse contamination on stream aquatic ecology. Four main contaminants of interest — nitrogen, phosphorus, sediment and pathogens — are being
investigated in four instrumented test catchments. In addition to the usual hydrological and water chemistry/quality parameters typically captured in catchment studies, field measurements at the test catchments include ecological
sampling, sediment dynamics, soil moisture dynamics, and groundwater levels and chemistry/quality, both during and between significant rainfall events. Spatial and temporal sampling of waters directly from the pathways of
interest is also being carried out.
Sixty-five percent of Ireland is underlain by poorly productive aquifers. In these hydrogeological settings, the main pathways delivering flow to streams are overland flow, interflow and shallow bedrock flow. Little is
known about the interflow pathway and its relative importance in delivery of flow and contaminants to the streams. Interflow can occur in both the topsoil and subsoil, and may include unsaturated matrix flow, bypass or macropore
flow, saturated flow in locally perched water tables and artificial field drainage.
Results to date from the test catchment experiments show that artificial field drains play an important role in the delivery of interflow to these streams, during and between rainfall events when antecedent conditions are
favourable. Hydrochemical mixing models, using silica and SAC254 (the absorbance of UV light at a wavelength of 254 nm which is a proxy for dissolved organic matter) as tracers, show that drain flow is an important end
member contributing to the stream and that proportionally, its contribution is relatively high.
Results from the study also demonstrate that waters originating from one pathway often mix with the waters from another, and are subsequently delivered to the stream at rates, and with chemical/quality characteristics,
that are not typical of either pathway. For example, pre-event shallow groundwater not far from the catchment divide comes up to the surface as rejected recharge during rainfall events and is rapidly delivered to the stream
via overland flow and/or artificial land drainage, bringing with it higher nitrate than would often be expected from a quickflow pathway contribution. This is contrary to the assumption often made in catchment studies that the
deeper hydrological pathways have slower response times in stream hydrographs during a rainfall event, and it emphasizes that it is critical to have a strong three-dimensional conceptual model as the basis for the interpretation
of catchment data.

Automatic decomposition and efficient semi-structured meshing of complex solids

In this paper, a novel approach to automatically sub-divide a complex geometry and apply an efficient mesh is presented. Following the identification and removal of thin-sheet regions from an arbitrary solid using the thick/thin decomposition approach developed by Robinson et al. [1], the technique here employs shape metrics generated using local sizing measures to identify long-slender regions within the thick body. A series of algorithms automatically partition the thick region into a non-manifold assembly of long-slender and complex sub-regions. A structured anisotropic mesh is applied to the thin-sheet and long-slender bodies, and the remaining complex bodies are filled with unstructured isotropic tetrahedra. The resulting semi-structured mesh possesses significantly fewer degrees of freedom than the equivalent unstructured mesh, demonstrating the effectiveness of the approach. The accuracy of the efficient meshes generated for a complex geometry is verified via a study that compares the results of a modal analysis with the results of an equivalent analysis on a dense tetrahedral mesh.

A VLSI architecture for multiplication, division and square root

A high-performance VLSI architecture to perform combined multiply-accumulate, divide, and square root operations is proposed. The circuit is highly regular, requires only minimal control, and can be reconfigured for every cycle. The execution time for each operation is the same. The combination of redundancy and pipelining results in a throughput independent of the wordsize of the array. With current CMOS technology, throughput rates in excess of 80 million operations per second are achievable.

VLSI processor for high-performance arithmetic computations

A high performance VLSI architecture to perform combined multiply-accumulate, divide, and square root operations is proposed. The circuit is highly regular, requires only minimal control, and can be pipelined right down to the bit level. The system can also be reconfigured on every cycle to perform one or more of these operations. The throughput rate for each operation is the same and is wordlength independent. This is achieved using redundant arithmetic. With current CMOS technology, throughput rates in excess of 80 million operations per second are expected.