Mathematical Modelling of Transient Thermography and Defect Sizing

The principle employed to obtain an image of a sub-surface defect by transient thermography is deceptively simple. A surface is heated by powerful flash lamps and subsequent thermal transients are recorded by an infrared camera. Defects cause perturbations in heat flow which are revealed by the camera. Whilst there is now a considerable body of practical experience of the application of the technique, there is rather less precise quantitative information about the image formation process that could lead to reliable defect sizing. In earlier papers [1,2] one of the authors considered circular air gap defects by treating them as buried uniformly heated disks. The thermal edge-effect occurring at the tip of a perfect crack-like defect was dealt with analytically by adapting the well established Wiener-Hopf [3] solution for the scattering of light or sound from the edge of a semi-infinite half-plane. The problem was solved in the frequency-domain, i.e. to obtain a thermal wave solution, and then a time-domain solution was obtained by a suitable transformation. The analysis showed an edge-effect amounting to a decay in temperature contrast over a distance of about a thermal diffusion length from the edge of the crack. A crucial feature of the edge-effect was the decay of thermal contrast to zero at the crack tip. This, and the edge-effect as a whole, is caused by the flow of heat around the crack tip from the hot upper surface of the crack to the cold under surface. The symmetry of this process ensures that there is no net flux increase for material in front of the crack tip

Thermographie Imaging of Defects in Anisotropie Composites

Composite materials are of increasing interest to the aerospace industry as a result of their weight versus performance characteristics. One of the disadvantages of composites is the high cost of fabrication and post inspection with conventional ultrasonic scanning systems. The high cost of inspection is driven by the need for scanning systems which can follow large curve surfaces. Additionally, either large water tanks or water squirters are required to couple the ultrasonics into the part. Thermographic techniques offer significant advantages over conventional ultrasonics by not requiring physical coupling between the part and sensor. The thermographic system can easily inspect large curved surface without requiring a surface following scanner. However, implementation of Thermal Nondestructive Evaluations (TNDE) for flaw detection in composite materials and structures requires determining its limit

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector

The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV

Search for R-parity-violating supersymmetry in events with four or more leptons in sqrt(s) =7 TeV pp collisions with the ATLAS detector

A search for new phenomena in final states with four or more leptons (electrons or muons) is presented. The analysis is based on 4.7 fb−1 of $\sqrt{s}=7\;\mathrm{TeV}$ proton-proton collisions delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in two signal regions: one that requires moderate values of missing transverse momentum and another that requires large effective mass. The results are interpreted in a simplified model of R-parity-violating supersymmetry in which a 95% CL exclusion region is set for charged wino masses up to 540 GeV. In an R-parity-violating MSUGRA/CMSSM model, values of m 1/2 up to 820 GeV are excluded for 10 < tan β < 40

Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector

This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}$and correspond to an integrated luminosity of$4.6\;{\rm f}{{{\rm b}}^{-1}}$. The measurement is performed by reconstructing the boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet centre-of-mass frame is used to suppress the large multi-jet background. The cross-section for events with a hadronically decaying W or Z boson, with transverse momentum${{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}$and pseudorapidity$|\eta |\lt 1.9$, is measured to be${{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques

High-Performance Work Systems and Organizational Performance in Emerging Economies: Evidence from MNEs in Turkey

This study examines the association between the usage of high-performance work systems (HPWS) by subsidiaries of multinational enterprises (MNEs) in Turkey and employee and subsidiary level outcomes. The study is based on a survey of 148 MNE subsidiaries operating in Turkey. The results show that the usage of HPWS has a significant positive impact on employee effectiveness. However, their impact on employee skills and development, and organizational financial performance are far less clear. Our findings highlight the extent to which HWPS need to be adapted to take account of context-specific institutional realities. © 2014 Springer-Verlag Berlin Heidelberg

PERAN ORANG TUA DALAM MEMBINA NILAI KARAKTER ANAK DI KECAMATAN SIMPANG TIGA ACEH BESAR

ABSTRAKRahmayanti KS, Sri. 2016. Peran Orang Tua Dalam Membina Nilai Karakter Anak di Kecamatan Simpang Tiga Kabupaten Aceh Besar. Skripsi, Jurusan Pendidikan Kesejahteraan Keluarga, Fakultas Keguruan dan Ilmu Pendidikan, Universitas Syiah Kuala. Pembimbing:(1)Dr. Anizar Ahmad, M.Pd., (2). Dra. Fitriana, M.SI.Kata Kunci: Nilai Karakter Anak, Peran Orang TuaPeran orang tua adalah partisipasi atau kesadaran jiwa orang tua untuk memperdulikan anaknya, terutama dalam hal memberikan dan memenuhi kebutuhan hidup anaknya baik dari segi sosial maupun material. Penelitian ini untuk mengetahui usaha orang tua dalam membina nilai karakter anak di Kecamatan Simpang Tiga Kabupaten Aceh Besar. Penelitian ini bertujuan untuk (1) mengetahui usaha yang dilakukan orang tua dalam membina nilai karakter anak dan (2) mengetahui sistem pengawasan yang diterapkan oleh orang tua terhadap anak. Metode yang digunakan dalam penelitian ini adalah metode deskriptif kuantitatif. Data penelitian ini bersumber dari orang tua yang memiliki anak usia 4 sampai 10 tahun berjumlah 28 keluarga, pengumpulan data menggunakan kuisioner. Pengolahan data penelitian ini menggunakan rumus persentase. Simpulan penelitian ini berpengaruh pada usaha orang tua dalam membina nilai karakter anak, walau sebagian kecil yang mengetahui nilai-nilai karakter, tetapi sebagian besar sudah berusaha menanamkan nilai karakter tersebut. Lebih dari setengah responden menanamkan nilai religius kepada anak dengan tujuan agar anak mempunyai akhlak yang mulia kedepannya. Sedangkan yang berperan dalam membina nilai karakter anak adalah suami dan istri. Sistem pengawasan yang diterapkan orang tua berpengaruh terhadap pembentukkan nilai karakter anak. Seluruh anak termasuk kedalam katagori anak yang mudah bersahabat. Penanaman nilai karakter pada anak di mulai pada awal masa kanak-kanak ketika berumur 2-6 tahun. Responden juga menerapkan perilaku disiplin kepada anak karena usia awal kanak-kanak merupakan usia yang masih rentan, dan akan meniru semua yang dikerjakan oleh orang tuanya. Saran untuk orang tua agar dapat mendidik anaknya dengan baik, tidak mengedepankan emosi, dapat meluangkan waktu, adanya komunikasi yang dibina orang tua dengan anak, dan jangan bersikap apatis terhadap apa yang dikerjakan sianak

Measurements of normalized differential cross sections for tt̄ production in pp collisions at √(s)=7 TeV using the ATLAS detector

Measurements of normalized differential cross sections for top-quark pair production are presented as a function of the top-quark transverse momentum, and of the mass, transverse momentum, and rapidity of the t¯t system, in proton–proton collisions at a center-of-mass energy of √s=7  TeV. The data set corresponds to an integrated luminosity of 4.6  fb−1, recorded in 2011 with the ATLAS detector at the CERN Large Hadron Collider. Events are selected in the lepton+jets channel, requiring exactly one lepton and at least four jets with at least one of the jets tagged as originating from a b-quark. The measured spectra are corrected for detector efficiency and resolution effects and are compared to several Monte Carlo simulations and theory calculations. The results are in fair agreement with the predictions in a wide kinematic range. Nevertheless, data distributions are softer than predicted for higher values of the mass of the t¯t system and of the top-quark transverse momentum. The measurements can also discriminate among different sets of parton distribution functions