394 research outputs found

    Ground Penetrating Radar Survey Across the Bok Bak Fault, Kedah, Malaysia

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    A ground penetrating radar (GPR) survey was done across the Bok Bak Fault zone in Baling, Kedah in order to investigate the shallow subsurface geology of the Bok Bak fault zone, its extension and associated weak zones within the study area. GPR data acquisition was compared with visual inspection on the slope of the outcrop. Ten GPR profiles were acquired using 250 MHz GPR frequency. Basic data processing and filtering to reduce some noise and unwanted signal was done using MALA RAMAC Ground Vision software. The data penetrate around 2 meters in depth for all survey lines. In most lines shows clear images of shallowest Bok Bak Fault (NW trending) as detected at distance of 28 m horizontal marker. It also exhibits several sets of faults as a result of Bok Bak Fault deformation, including the conjugate NE trending fault (Lubok Merbau Fault). Active seismicity encompasses the Malay-Thai Peninsular trigger the changes of Bok Bak Fault dipping direction, steeper dips of conjugate faults and faults or fractures rotational movement. Survei menggunakan ground penetrating radar (GPR) yang dijalankan melalui kawasan patahan Bok Bak di Baling, Kedah adalah bertujuan untuk menyelidiki geologi dangkal zona bawah tanah patahan Bok Bak, kemenerusannya beserta zona-zona lemah di sekitar patahan tersebut. Data pengukuran GPR yang diperoleh kemudian dibandingkan dengan hasil pengamatan langsung pada tebing singkapan. Sepuluh profil GPR telah diperoleh menggunakan frekuensi 250 MHz. Pemrosesan dasar dan penapisan data untuk mengurangi sinyal-sinyal yang tidak dikehendaki berikut gangguan-gangguan suara dilakukan dengan piranti halus MALA RAMAC Ground Vision. Data mampu menembus hingga kedalaman 2 meter untuk semua garis survei. Umumnya garis survei menunjukkan gambar yang jelas untuk patahan Bok Bak (ke arah Barat Laut) sebagaimana terdeteksi di jarak 28 m pada penanda horisontal. Beberapa set patahan yang dihasilkan dari deformasi patahan Bok Bak juga dapat dideteksi, termasuk pasangan patahan yang ke arah Timur Laut (patahan Lubok Merbau). Pergerakan aktif seismik di Peninsula Malaya-Thailand turut memicu Perubahan arah kemiringan patahan Bok Bak, menjadikan kemiringan pasangan patahan lebih curam, dan pergerakan rotasi patahan dan retakan

    Validation of requirements for transformation of an urban district to a smart city

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    The concept of a smart city is still debatable and yet gives attention to every country around the globe to provide their community with a better quality of life. New ideas for the development of a smart city have always evolved to enhance the quality, performance, and interactivity of services. This paper presents a model of a smart city based on the comparison of the chosen smart cities in the world and used the model to validate the requirements for the transformation of an urban district to a smart city. The proposed model for a smart city in this paper focuses on two major components, which are by utilizing IoTs (Internet of Things) in forming a model for a smart city and incorporating culture diversity. The relationship of components and culture influence are the foundation of designing the model of a smart city. In this research, the model of a smart city has been validated based on the requirements analysis from the survey instrument and the results show that the average mean of each element used is more than 4 out of 5. The model of a smart city can be used as a guideline for transformation of an urban district to a smart city

    Nuclear Modification Factors for Hadrons At Forward and Backward Rapidities in Deuteron-Gold Collisions at sqrt(s_NN) = 200 GeV

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    We report on charged hadron production in deuteron-gold reactions at sqrt(s_NN) = 200 GeV. Our measurements in the deuteron-direction cover 1.4 < eta < 2.2, referred to as forward rapidity, and in the gold-direction -2.0 < eta < -1.4, referred to as backward rapidity, and a transverse momentum range p_T = 0.5-4.0 GeV/c. We compare the relative yields for different deuteron-gold collision centrality classes. We observe a suppression relative to binary collision scaling at forward rapidity, sensitive to low momentum fraction (x) partons in the gold nucleus, and an enhancement at backward rapidity, sensitive to high momentum fraction partons in the gold nucleus.Comment: 330 authors, 6 pages text, 4 figures, REVTeX4. Published in Physical Review Letters. Minor changes over previous version in response to referee and editor comments, plus updating of references. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are publicly available at http://www.phenix.bnl.gov/papers.htm

    Centrality dependence of charged hadron production in deuteron+gold and nucleon+gold collisions at sqrt(s_NN)=200 GeV

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    We present transverse momentum (p_T) spectra of charged hadrons measured in deuteron-gold and nucleon-gold collisions at \sqrts = 200 GeV for four centrality classes. Nucleon-gold collisions were selected by tagging events in which a spectator nucleon was observed in one of two forward rapidity detectors. The spectra and yields were investigated as a function of the number of binary nucleon-nucleon collisions, \nu, suffered by deuteron nucleons. A comparison of charged particle yields to those in p+p collisions show that the yield per nucleon-nucleon collision saturates with \nu for high momentum particles. We also present the charged hadron to neutral pion ratios as a function of p_T.Comment: 330 authors, 15 pages text, 16 figures, 3 tables. Submitted to Phys. Rev. Lett. v2 has minor changes to reflect revisions during review process. 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

    High-pT pi^zero Production with Respect to the Reaction Plane in Au + Au Collisions at sqrt(s_NN) = 200 GeV

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    Measurements of the azimuthal anisotropy of high-\pT neutral pion neutral pion production in Au+Au collisions at sqrt(s_NN) = 200 GeV by the PHENIX experiment are presented. The data included in this paper were collected during the 2004 RHIC running period and represent approximately an order of magnitude increase in the number of analyzed events relative to previously published results. Azimuthal angle distributions of pi^0s detected in the PHENIX electromagnetic calorimeters are measured relative to the reaction plane determined event-by-event using the forward and backward beam-beam counters. Amplitudes of the second Fourier component (v_2) of the angular distributions are presented as a function of pi^0 transverse momentum p_T for different bins in collision centrality. Measured reaction plane dependent pi^0 yields are used to determine the azimuthal dependence of the pi^0 suppression as a function of p_T, R_AA (Delta phi,p_T). A jet-quenching motivated geometric analysis is presented that attempts to simultaneously describe the centrality dependence and reaction plane angle dependence of the pi^0 suppression in terms of the path lengths of hypothetical parent partons in the medium. This set of results allows for a detailed examination of the influence of geometry in the collision region, and of the interplay between collective flow and jet-quenching effects along the azimuthal axis.Comment: 344 authors, 35 pages text, RevTeX-4, 24 figures, 8 tables. Submitted to Physical Review

    Particle-species dependent modification of jet-induced correlations in Au+Au collisions at sqrt(s_NN) = 200 GeV

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    We report PHENIX measurements of the correlation of a trigger hadron at intermediate transverse momentum (2.5<p_{T,trig}<4 GeV/c), with associated mesons or baryons at lower p_{T,assoc}, in Au+Au collisions at sqrt(s_NN) = 200 GeV. The jet correlations for both baryons and mesons show similar shape alterations as a function of centrality, characteristic of strong modification of the away-side jet. The ratio of jet-associated baryons to mesons for this jet increases with centrality and p_{T,assoc} and, in the most central collisions, reaches a value similar to that for inclusive measurements. This trend is incompatible with in-vacuum fragmentation, but could be due to jet-like contributions from correlated soft partons which recombine upon hadronization.Comment: 344 authors, 4 pages text, RevTeX, 4 figures. Submitted to Physical Review Letters. 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

    Transverse-energy distributions at midrapidity in pp++pp, dd++Au, and Au++Au collisions at sNN=62.4\sqrt{s_{_{NN}}}=62.4--200~GeV and implications for particle-production models

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    Measurements of the midrapidity transverse energy distribution, d\Et/d\eta, are presented for pp++pp, dd++Au, and Au++Au collisions at sNN=200\sqrt{s_{_{NN}}}=200 GeV and additionally for Au++Au collisions at sNN=62.4\sqrt{s_{_{NN}}}=62.4 and 130 GeV. The d\Et/d\eta distributions are first compared with the number of nucleon participants NpartN_{\rm part}, number of binary collisions NcollN_{\rm coll}, and number of constituent-quark participants NqpN_{qp} calculated from a Glauber model based on the nuclear geometry. For Au++Au, \mean{d\Et/d\eta}/N_{\rm part} increases with NpartN_{\rm part}, while \mean{d\Et/d\eta}/N_{qp} is approximately constant for all three energies. This indicates that the two component ansatz, dET/dη(1x)Npart/2+xNcolldE_{T}/d\eta \propto (1-x) N_{\rm part}/2 + x N_{\rm coll}, which has been used to represent ETE_T distributions, is simply a proxy for NqpN_{qp}, and that the NcollN_{\rm coll} term does not represent a hard-scattering component in ETE_T distributions. The dET/dηdE_{T}/d\eta distributions of Au++Au and dd++Au are then calculated from the measured pp++pp ETE_T distribution using two models that both reproduce the Au++Au data. However, while the number-of-constituent-quark-participant model agrees well with the dd++Au data, the additive-quark model does not.Comment: 391 authors, 24 pages, 19 figures, and 15 Tables. Submitted to Phys. Rev. C. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are publicly available at http://www.phenix.bnl.gov/papers.htm

    High transverse momentum eta meson production in p+p, d+Au and Au+Au collisions at sqrt(s_NN) = 200 GeV

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    Inclusive transverse momentum spectra of eta mesons in the range p_T~2-12 GeV/c have been measured at mid-rapidity (|\eta| < 0,35) by the PHENIX experiment at RHIC in p+p, d+Au and Au+Au collisions at sqrt(s_NN) = 200 GeV. The eta mesons are reconstructed through their eta--> \gamma\gamma channel for the three colliding systems as well as through the eta-->pi^0 pi+ pi- decay mode in p+p and d+Au collisions. The nuclear modification factor in d+Au collisions, R_dAu(p_T~1.0-1.1, suggests at most only modest p_T broadening ("Cronin enhancement"). In central Au+Au reactions, the eta yields are significantly suppressed, with R_AuAu(pT)~0.2. The ratio of eta to pi^0 yields is approximately constant as a function of p_T for the three colliding systems in agreement with the high-p_T world average of R_eta/pi^0 \approx 0.5 in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions for a wide range of center-of-mass energies [sqrt(s_NN)~3-1800 GeV] as well as, for high scaled momentum x_p, in e+e- annihilations at sqrt(s)=91.2 GeV. These results are consistent with a scenario where high-p_T eta production in nuclear collisions at RHIC is largely unaffected by initial-state effects, but where light-quark mesons (pi^0;eta) are equally suppressed due to final-state interactions of the parent partons in the dense medium produced in Au+Au reactions.Comment: 391 authors, NN pages text, RevTeX4, figures, tables. Submitted to Physical Review C. 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

    Azimuthal Angle Correlations for Rapidity Separated Hadron Pairs in d+Au Collisions at sqrt(s_NN) = 200 GeV

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    We report on two-particle azimuthal angle correlations between charged hadrons at forward/backward (deuteron/gold going direction) rapidity and charged hadrons at mid-rapidity in deuteron-gold (d+Au) and proton-proton (p+p) collisions at sqrt(s_NN) = 200 GeV. Jet structures are observed in the correlations which we quantify in terms of the conditional yield and angular width of away side partners. The kinematic region studied here samples partons in the gold nucleus carrying nucleon momentum fraction x~0.1 to x~0.01. Within this range, we find no x dependence of the jet structure in d+Au collisions.Comment: 330 authors, 6 pages text, 4 figures, no tables. Submitted to Phys. Rev. Lett. 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

    Energy Loss and Flow of Heavy Quarks in Au+Au Collisions at sqrt(s_NN) = 200 GeV

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    The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) has measured electrons from heavy flavor (charm and bottom) decays for 0.3 < p_T < 9 GeV/c at midrapidity (|y| < 0.35) in Au+Au collisions at sqrt(s_NN) = 200 GeV. The nuclear modification factor R_AA relative to p+p collisions shows a strong suppression in central Au+Au collisions, indicating substantial energy loss of heavy quarks in the medium produced at RHIC. A large azimuthal anisotropy, v_2, with respect to the reaction plane is observed for 0.5 < p_T < 5 GeV/c indicating non-zero heavy flavor elliptic flow. Both R_AA and v_2 show a p_T dependence different from those of neutral pions. A comparison to transport models which simultaneously describe R_AA(p_T) and v_2(p_T) suggests that the viscosity to entropy density ratio is close to the conjectured quantum lower bound, i.e., near a perfect fluid.Comment: v2 replaced Fig. 3 to fix an error in using a wrong theory curve; v3 minor changes in review process, including last 2 sentences of abstract. 422 authors, 58 institutions, 6 pages text, 3 figures, REVTeX4. Submitted to Physical Review Letters. Plain text data tables for the points plotted in figures available at http://www.phenix.bnl.gov/papers.htm
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