This paper discusses the effect of a new skylight prototype on the energy and environmental performance of an office building. It has been considered as a priority the study of the factors that relate daylighting and energy, as well as, to a certain extent, other aspects such as ventilation and insulation. Many architectural designs are presented as correct if the thermal requirements alone are met, even at the risk of later energy waste in lighting devices and visual or physical discomfort. On the other hand, large glazed areas allow more daylight into a space, but they may also allow excessive heat gains or losses which increase the air-conditioning cooling or heating load. To avoid these problems, we have considered the combined effect of daylight and energy from the beginning of the skylight design-process. The environmental analysis tool Ecotect has been used together with a daylighting software based on configuration factors that we have used in former PLEA conferences to study the problems of direct sun over architectural structures. This question can not be treated adequately with conventional programs for overcast skies. The skylights have already been constructed and on-site measurements in the offices have been taken to complement the computer simulations data. The results show that it is possible to achieve energy saving and high daylight levels in winter without increasing heat loads during the summer.

Arequipa, an UNESCO World Cultural Heritage site, is a good example of how the harmonious interaction between climate, local materials, construction techniques and traditions can generate architectural solutions with positive values in terms of quality of life and cultural identity. The paper discusses under an environmental prism and with the help of scientific instruments the architectural patterns of the city. On-site measurements and energy computer simulations have been used to study the effect of climate factors on the adaptation process of the European models to a new natural surroundings and cultural context. The research has been focused on the study of traditional typologies by using a methodology in which environmental and technological aspects are related. The traditional architecture of Arequipa had never been analyzed before using real measures and computer science technologies. The research contributes objective and novel data about the advantages of vernacular solutions in light of a modern environmentally aware evaluation.

We use observedUVthrough near-IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal Type Ia supernovae (SNe Ia) and to examine its individual peculiarities. As a benchmark, we use a delayed-detonationmodel with a progenitormetallicity of Z⊙/20. We study the sensitivity of features to variations in progenitor metallicity, the outer density profile, and the distribution of radioactive nickel. The effect of metallicity variations in the progenitor have a relatively small effect on the synthetic spectra. We also find that the abundance stratification of SN 2011fe resembles closely that of a delayed-detonation model with a transition density that has been fit to other Branch-normal SNe Ia. At early times, the model photosphere is formed in material with velocities that are too high, indicating that the photosphere recedes too slowly or that SN 2011fe has a lower specific energy in the outer ≈0.1 M⊙ than does the model. We discuss several explanations for the discrepancies. Finally, we examine variations in both the spectral energy distribution and in the colours due to variations in the progenitor metallicity, which suggests that colours are only weak indicators for the progenitor metallicity, in the particular explosion model that we have studied. We do find that the flux in the U band is significantly higher at maximum light in the solar metallicity model than in the lower metallicity model and the lower metallicity model much better matches the observed spectrum.

The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy √s= 7 TeV, were measured in the central pseudorapidity region {pipe}η{pipe} < 1. Comparisons are made with previous measurements at √s = 0.9 TeV and 2.36 TeV. At √s = 7 TeV, for events with at least one charged particle in {pipe}η{pipe} < 1, we obtain dNch/dη = 6.01 ± 0.01(stat.)+0.20-0.12(syst.). This corresponds to an increase of 57.6% ± 0.4%(stat.)+3.6-1.8%(syst.) relative to collisions at 0.9 TeV, significantly higher than calculations from commonly used models. The multiplicity distribution at 7 TeV is described fairly well by the negative binomial distribution. © 2010 CERN for the benefit of the ALICE collaboration.

On 23rd November 2009, during the early commissioning of the CERN Large Hadron Collider (LHC), two counter-rotating proton bunches were circulated for the first time concurrently in the machine, at the LHC injection energy of 450 GeV per beam. Although the proton intensity was very low, with only one pilot bunch per beam, and no systematic attempt was made to optimize the collision optics, all LHC experiments reported a number of collision candidates. In the ALICE experiment, the collision region was centred very well in both the longitudinal and transverse directions and 284 events were recorded in coincidence with the two passing proton bunches. The events were immediately reconstructed and analyzed both online and offline. We have used these events to measure the pseudorapidity density of charged primary particles in the central region. In the range |η|<0.5, we obtain dNch/dη=3. 10±0. 13(stat.)±0. 22(syst.) for all inelastic interactions, and dNch/dη=3.51±0. 15(stat.)±0. 25(syst.) for non-single diffractive interactions. These results are consistent with previous measurements in proton-antiproton interactions at the same centre-of-mass energy at the CERN Spp̄S collider. They also illustrate the excellent functioning and rapid progress of the LHC accelerator, and of both the hardware and software of the ALICE experiment, in this early start-up phase. © CERN 2009.

Charged-particle production was studied in proton-proton collisions collected at the LHC with the ALICE detector at centre-of-mass energies 0.9 TeV and 2.36 TeV in the pseudorapidity range {pipe}η{pipe}<1.4. In the central region ({pipe}η{pipe}<0.5), at 0.9 TeV, we measure charged-particle pseudorapidity density dNch/dη= 3.02 ± 0.01 (stat.)-0.05+0.08(syst.) for inelastic interactions, and dNch/dη = 3.58 ± 0.01 (stat.)-0.12+0.12(syst.) for non-single-diffractive interactions. At 2.36 TeV, we find dNch/dη = 3.77 ± 0.01 (stat.)-0.12+0.25(syst.) for inelastic, and dNch/dη = 4.43 ± 0.01(stat.)-0.12+0.17(syst.) for non-single-diffractive collisions. The relative increase in charged-particle multiplicity from the lower to higher energy is 24.7% ± 0.5%(stat.)-2.8+5.7(syst.) for inelastic and 23.7% ± 0.5%(stat.)-1.1+4.6% 1.1%(syst.) for non-single-diffractive interactions. This increase is consistent with that reported by the CMS collaboration for non-single-diffractive events and larger than that found by a number of commonly used models. The multiplicity distribution was measured in different pseudorapidity intervals and studied in terms of KNO variables at both energies. The results are compared to proton-antiproton data and to model predictions. © 2010 CERN for the benefit of the ALICE collaboration.