263 research outputs found
Comments of Board of Trustees on ILCA Mission Report
Letter from the Director General of ILCA, D. J. Pratt, conveying the comments of ILCA Board and Program Committee members on the July 1979 Report of the Second TAC Mission to ILCA. Includes general comments regarding the structure and length of the report, disagreement with particular observations and interpretations including updates on developments since the initial report's presentation at TAC 22, and points requiring clarification. Agenda document, TAC 23rd Meeting, February 1980
Target value design: using collaboration and a lean approach to reduce construction cost
Target Costing is an effective management technique that has been used in manufacturing for decades to achieve cost predictability during new products development. Adoption of this technique promises benefits for the construction industry as it struggles to raise the number of successful outcomes and certainty of project delivery in terms of cost, quality and time. Target Value Design is a management approach that takes the best features of Target Costing and adapts them to the peculiarities of construction. In this paper the concept of Target Value Design is introduced based on the results of action research carried out on 12 construction projects in the USA. It has been shown that systemic application of Target Value Design leads to significant improvement of project performance – the final cost of projects was on average 15% less than market cost. The construction industry already has approaches that have similarities with elements of the Target Value Design process or uses the same terminology, e.g. Partnering and Target Cost Contracts, Cost planning, etc. Following an exploration of the similarities and differences Target Value Design is positioned as a form of Target Costing for construction that offers a more reliable route to successful projects outcomes
Stimulated Raman scattering of picosecond light pulses in hydrogen, deuterium and methane
Experimental results are presented on stimulated Raman scattering of short pulses of approximately 100 ps duration in H2, D2, and CH4, both in capillary waveguides and in a tight focusing geometry. Experimentally determined thresholds are in good agreement with calculation. Low thresholds (<20 µJ) are observed in CH4 and preliminary results using a mode-locked dye laser as pump indicate a useful source of tunable short pulse radiation in the near infrared
Nonlinear Stress Fluctuation Dynamics of Sheared Disordered Wet Foam
Sheared wet foam, which stores elastic energy in bubble deformations, relaxes
stress through bubble rearrangements. The intermittency of bubble
rearrangements in foam leads to effectively stochastic drops in stress that are
followed by periods of elastic increase. We investigate global characteristics
of highly disordered foams over three decades of strain rate and almost two
decades of system size. We characterize the behavior using a range of measures:
average stress, distribution of stress drops, rate of stress drops, and a
normalized fluctuation intensity. There is essentially no dependence on system
size. As a function of strain rate, there is a change in behavior around shear
rates of .Comment: accepted to Physical Review
The manipulation of midsole properties to alter impact characteristics in walking
The midsole of footwear can provide an opportunity to attenuate the impact at the foot-ground interface. The present study was undertaken to quantify impact in walking in different footwear midsoles, comparing footwear thickness and hardness variations. Methods: Footbed thickness (28-41 mm) and hardness (30-55 Shore A) were varied independently in 7 flip-flops. Thirteen subjects walked in the footwear variations on a level walkway in the gait laboratory as lower limb kinematics, vertical ground reaction force and peak positive axial tibial acceleration were quantified. Peak magnitude and time of the acceleration were quantified and the heel-strike transient was characterised for comparison between conditions with a repeated-measures ANOVA. Thickness and hardness variations were also compared using a drop-test protocol to replicate walking. Results: Lower limb joint angles did not vary at heel-strike, however, a faster vertical heel-velocity was recorded in the softer midsoles (e.g. 55 Shore A = -0.294±0.055, 30 Shore A= -0.328±0.052, p<.001). Varying the hardness of the midsoles also significantly altered tibial acceleration and force variables, however limited significant differences existed between the thickness variations in walking. Increasing the hardness of the heel section of the footwear increased the peak positive axial tibial acceleration values, for example increasing Shore A from 30 to 40 resulted in a 35% increase in this variable. Concurrently, the occurrence of heel-strike transients increased from 5.8% in the 30 Shore A condition to 22.5%, 46.7% and 71.7% of all trials in the 40, 47 and 55 Shore A conditions respectively. The drop-test protocol replicated the differences evident in the walking protocol despite magnitudes being elevated. Conclusion: Modifying midsole properties of flip-flop footwear, particularly hardness, alters the gait kinematics and the shock experienced by the wearer in walking. This may pose benefits in terms of comfort and reduction in loading to the lower limb, however the influence on foot motion at initial contact and footwear longevity should be further quantified
Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration
Extensive experimental data from high-energy nucleus-nucleus collisions were
recorded using the PHENIX detector at the Relativistic Heavy Ion Collider
(RHIC). The comprehensive set of measurements from the first three years of
RHIC operation includes charged particle multiplicities, transverse energy,
yield ratios and spectra of identified hadrons in a wide range of transverse
momenta (p_T), elliptic flow, two-particle correlations, non-statistical
fluctuations, and suppression of particle production at high p_T. The results
are examined with an emphasis on implications for the formation of a new state
of dense matter. We find that the state of matter created at RHIC cannot be
described in terms of ordinary color neutral hadrons.Comment: 510 authors, 127 pages text, 56 figures, 1 tables, LaTeX. Submitted
to Nuclear Physics A as a regular article; v3 has minor changes in response
to referee comments. Plain text data tables for the points plotted in figures
for this and previous PHENIX publications are (or will be) publicly available
at http://www.phenix.bnl.gov/papers.htm
Planck intermediate results. VIII. Filaments between interacting clusters
About half of the baryons of the Universe are expected to be in the form of
filaments of hot and low density intergalactic medium. Most of these baryons
remain undetected even by the most advanced X-ray observatories which are
limited in sensitivity to the diffuse low density medium. The Planck satellite
has provided hundreds of detections of the hot gas in clusters of galaxies via
the thermal Sunyaev-Zel'dovich (tSZ) effect and is an ideal instrument for
studying extended low density media through the tSZ effect. In this paper we
use the Planck data to search for signatures of a fraction of these missing
baryons between pairs of galaxy clusters. Cluster pairs are good candidates for
searching for the hotter and denser phase of the intergalactic medium (which is
more easily observed through the SZ effect). Using an X-ray catalogue of
clusters and the Planck data, we select physical pairs of clusters as
candidates. Using the Planck data we construct a local map of the tSZ effect
centered on each pair of galaxy clusters. ROSAT data is used to construct X-ray
maps of these pairs. After having modelled and subtracted the tSZ effect and
X-ray emission for each cluster in the pair we study the residuals on both the
SZ and X-ray maps. For the merging cluster pair A399-A401 we observe a
significant tSZ effect signal in the intercluster region beyond the virial
radii of the clusters. A joint X-ray SZ analysis allows us to constrain the
temperature and density of this intercluster medium. We obtain a temperature of
kT = 7.1 +- 0.9, keV (consistent with previous estimates) and a baryon density
of (3.7 +- 0.2)x10^-4, cm^-3. The Planck satellite mission has provided the
first SZ detection of the hot and diffuse intercluster gas.Comment: Accepted by A&
Longitudinal scaling property of the charge balance function in Au + Au collisions at 200 GeV
We present measurements of the charge balance function, from the charged
particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au
collisions at 200 GeV using the STAR detector at RHIC. We observe that the
balance function is boost-invariant within the pseudorapidity coverage [-1.3,
1.3]. The balance function properly scaled by the width of the observed
pseudorapidity window does not depend on the position or size of the
pseudorapidity window. This scaling property also holds for particles in
different transverse momentum ranges. In addition, we find that the width of
the balance function decreases monotonically with increasing transverse
momentum for all centrality classes.Comment: 6 pages, 3 figure
Measurement of an Elongation of the Pion Source in Z Decays
We measure Bose-Einstein correlations between like-sign charged pion pairs in
hadronic Z decays with the L3 detector at LEP. The analysis is performed in
three dimensions in the longitudinal center-of-mass system. The pion source is
found to be elongated along the thrust axis with a ratio of transverse to
longitudinal radius of
The Green, Green Grass of Home: an archaeo-ecological approach to pastoralist settlement in central Kenya
© 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This paper considers the ecological residues of pastoralist occupation at the site of Maili Sita in Laikipia, central Kenya, drawing links with the archaeological record so as to contribute a fresh approach to the ephemeral settlement sites of mobile herding communities, a methodological aspect of African archaeology that remains problematic. Variations in the geochemical and micromorphological composition of soils along transects across the site are compared with vegetation distributions and satellite imagery to propose an occupation pattern not dissimilar to contemporary Cushitic-speaking groups further north. We argue that Maili Sita exemplifies the broad migratory and cultural exchange networks in place during the mid- to late second millennium AD, with pastoralist occupants who were both physically and culturally mobile.British Academy (2002-5 Funding)
European Union - Marie Curie Initiatives (EXT grant 2007-11
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