The sound insulation of autoclaved aerated concrete panels lined with gypsum plasterboard

This paper gives the results of 27 laboratory measurements of the sound insulation of 75mm thick tongue and groove autoclaved aerated concrete (AAC) panels with stated nominal dry density of 510kg/m3 (a surface density of 38.2kg/m2).which are lined with 13mm thick gypsum plasterboard. Two configurations that are presently common forms of construction in a region of Australia were tested; 1. Furring channel one side and stud wall the other that maintained an overall wall width of 243mm, and 2. Direct fix one side and stud wall the other. In both cases the gypsum plasterboard is mounted on 64mm steel studs. The gap between the panels and the steel studs is 20, 35 or 48mm. With the exception of one empty cavity, the cavity on this side contains 11kg/m3 glass fibre batts with thickness of 50, 75, 90 or 110mm. On the other side of the panels, the gypsum plasterboard is mounted on furring channels and adjustable clips which are screwed to the panels or in 6 cases directly screwed to the panels. Except for the directly screwed cases, the gap between the panels and the gypsum plasterboard is 30, 43 or 58mm. The cavity is empty or contains 50 or 70mm thick 11kg/m3 glass fibre batts or 25mm thick 24kg/m3 glass fibre batts. The 13mm gypsum plasterboard has nominal surface densities of 7.2, 8.5 or 10.5kg/m2. The aim was to develop a system which has a laboratory measured Rw+Ctr equal to or greater than 50dB which is required by the National Construction Code (NCC) of Australia for walls between separate dwellings. A system with cavities on both sides of the wall is desirable because it allows services to be accommodated without the need for chasing which is not permitted. The undesirable effect is a resultant large Ctr making it difficult to achieve an Rw +Ctr equal to or greater than 50dB

Study of neutron irradiation effects in Depleted CMOS detector structures

In this paper results of Edge-TCT and I-V measurements with passive test structures made in LFoundry 150 nm HV-CMOS process on p-type substrates with different initial resistivities ranging from 0.5 to 3 k$\Omega$cm are presented. Samples were irradiated with reactor neutrons up to a fluence of 2$\cdot$10$^{15}$ n$_{\mathrm{eq}}$/cm$^2$. Depletion depth was measured with Edge-TCT. Effective space charge concentration $N_{\mathrm{eff}}$ was estimated from the dependence of depletion depth on bias voltage and studied as a function of neutron fluence. Dependence of $N_{\mathrm{eff}}$ on fluence changes with initial acceptor concentration in agreement with other measurements with p-type silicon. Long term accelerated annealing study of $N_{\mathrm{eff}}$ and detector current up to 1280 minutes at 60$^\circ$C was made. It was found that $N_{\mathrm{eff}}$ and current in reverse biased detector behaves as expected for irradiated silicon

Search for dark mesons decaying to top and bottom quarks in proton-proton collisions at √s = 13 TeV with the ATLAS detector

A search for dark mesons originating from strongly-coupled, SU(2) dark favor symmetry conserving models and decaying gaugephobically to pure Standard Model final states containing top and bottom quarks is presented. The search targets fully hadronic final states and final states with exactly one electron or muon and multiple jets. The analyzed data sample corresponds to an integrated luminosity of 140 fb−1 of proton-proton collisions collected at √s = 13 TeV with the ATLAS detector at the Large Hadron Collider. No significant excess over the Standard Model background expectation is observed and the results are used to set the first direct constraints on this type of model. The two-dimensional signal space of dark pion masses mπD and dark rho-meson masses mρD is scanned. For mπD /mρD = 0.45, dark pions with masses mπD < 940 GeV are excluded at the 95% CL, while for mπD /mρD = 0.25 masses mπD < 740 GeV are excluded

Combination of searches for Higgs boson decays into a photon and a massless dark photon using pp collisions at √s = 13 TeV with the ATLAS detector

A combination of searches for Higgs boson decays into a visible photon and a massless dark photon (H → γγd) is presented using 139 fb−1 of proton-proton collision data at a centre-of-mass energy of √s = 13 TeV recorded by the ATLAS detector at the Large Hadron Collider. The observed (expected) 95% confidence level upper limit on the Standard Model Higgs boson decay branching ratio is determined to be B(H → γγd) < 1.3% (1.5)%. The search is also sensitive to higher-mass Higgs bosons decaying into the same final state. The observed (expected) 95% confidence level limit on the cross-section times branching ratio ranges from 16 fb (20 fb) for mH = 400 GeV to 1.0 fb (1.5 fb) for mH = 3 TeV. Results are also interpreted in the context of a minimal simplified model

Assessment of problem solving ability in novice programmers.

Problem Solving (PS) skills allow students to handle problems within an educational context. PS is a core competence of Computer Science education and affects programming success. In this vein, this paper aims to investigate PS ability performance in primary school pupils of a computer course, implemented according to the Neo-Piagetian theory of cognitive development. The study included 945 Slovenian pupils, ranging from fourth to sixth grade. The effects of gender, age and consecutive years of attending the course were examined on pupils' PS ability at the pre-operational and concrete operational stages. Pupils completed a survey questionnaire with four types of tasks (a series of statements, if-statements, loops and variables) at both stages. The analysis revealed three findings: the performance of PS ability in all tasks was, at the pre-operational stage, associated positively with performance at the concrete operational stage; there were no gender differences in PS performance at both stages, and both the grade and consecutive year of taking the computer course had an effect on PS ability performance at both stages. Those in the lowest grade and those taking the course for the first year reported lower performances than their older counterparts. These findings may help curriculum designers across the world develop efficient approaches to teaching computer courses

Measurements of time resolution of the RD50-MPW2 DMAPS prototype using TCT and ⁹⁰Sr

Abstract Results in this paper present an in-depth study of time resolution for active pixels of the RD50-MPW2 prototype CMOS particle detector. Measurement techniques employed include Backside- and Edge-TCT configurations, in addition to electrons from a  90Sr source. A sample irradiated to 5 · 1014 neq/cm2 was used to study the effect of radiation damage. Timing performance was evaluated for the entire pixel matrix and with positional sensitivity within individual pixels as a function of the deposited charge. Time resolution obtained with TCT is seen to be uniform throughout the pixel's central region with approx. 220 ps at 12 ke- of deposited charge, degrading at the edges and lower values of deposited charge. 90Sr measurements show a slightly worse time resolution as a result of delayed events coming from the peripheral areas of the pixel.</jats:p