118 research outputs found
Geological Effect on GPR System Due to Soil Properties in Malaysia
This paper present the measurement of dielectric properties of soil in Malaysia in three differences condition which are normal condition (ambience), heated (up to 50 OC) and wet condition (10 % water content). Eight (8) samples of soil have been collected in the local region and was measured in the frequency range from 0.5 GHz to 3.5 GHz for Ground Penetrating Radar (GPR) applications. The measurement of the dielectric properties has been conducted using Agilent high temperature probe (Model) integrated with Performance Network Analyzer (PNA E8362B). The uncertainties in measurement process, especially dealing with measurement data have been considered in order to eliminate the probability of error during the measurement. The measured result for permittivity and loss factor of the measured samples are tabulated in graphs and the analysis of the measured data are discussed in this paper
Study of 5.8 GHz Band-Stop Frequency Selective Surface (FSS)
This paper presents the study of 5.8 GHz frequency selective surface (FSS) acts as a band stop to eliminate unwanted radiation signal at 5.8GHz. The FSS was designed using computer simulation technology (CST) Microwave Studio software. The paper shows the comparison of square loop, octagon loop and hexagon loop of Band stop FSS (BSFSS) performance at 5.8 GHz. Besides, the BSFSS design using four different type of dielectric substrate such as FR-4, TLY-5, Roger RT5870 and Roger RT5880 were compared. The results obviously show that the Rogers RY5880 has the attenuation -44.72 dB. The fabricated FSS were measured by using free space technique with two horn antennas connected to performance network analyzer (PNA). The measured and simulated results were compared. The results show that the square loop FSS structure have the better attenuation -26.76 dB (simulated) and -38.34 dB (measured) at 5.8 GHz
Effect of polymer-modified bitumen and reclaimed asphalt pavement on the physical properties of bitumen
The high cost of road construction due to the energy required for new material production
and the environmental impact necessitates the use of reclaimed asphalt pavement (RAP) and other
waste materials. This paper examined the effect of using RAP with a PET additive as a rejuvenator.
PET additive (2%) was added to the virgin binder (VB) of 60/70 penetration grade to form a
Polymer modified bitumen (PMB). RAP percentages used were 30, 40, and 50%, respectively. The
physical properties were examined using the penetration, softening point, and ductility. The results
show that the physical properties of RAP were improved by utilizing Rap binder (RB) and PMB
mix ratio. The penetration and ductility values increased by 46.4% and 66.7%, respectively, with
the PMB (30): RB (70) ratio blend, compared to RB: VB blend. This suggests a reduction in brittle
behavior and less stiffness with the addition of PMB in the blend, enhancing the flexibility of the
RAP. Although both mixtures blended with RB exhibited softening points within the acceptable
range, improved performance was observed with RB/PMB mix blend over RB/VB blend when used
in hot asphalt mixtur
Effect of polymer-modified bitumen and reclaimed asphalt pavement on the physical properties of bitumen
The high cost of road construction due to the energy required for new material production
and the environmental impact necessitates the use of reclaimed asphalt pavement (RAP) and other
waste materials. This paper examined the effect of using RAP with a PET additive as a rejuvenator.
PET additive (2%) was added to the virgin binder (VB) of 60/70 penetration grade to form a
Polymer modified bitumen (PMB). RAP percentages used were 30, 40, and 50%, respectively. The
physical properties were examined using the penetration, softening point, and ductility. The results
show that the physical properties of RAP were improved by utilizing Rap binder (RB) and PMB
mix ratio. The penetration and ductility values increased by 46.4% and 66.7%, respectively, with
the PMB (30): RB (70) ratio blend, compared to RB: VB blend. This suggests a reduction in brittle
behavior and less stiffness with the addition of PMB in the blend, enhancing the flexibility of the
RAP. Although both mixtures blended with RB exhibited softening points within the acceptable
range, improved performance was observed with RB/PMB mix blend over RB/VB blend when used
in hot asphalt mixtur
The SCUBA-2 Cosmology Legacy Survey: Ultraluminous star-forming galaxies in a z=1.6 cluster
We analyze new SCUBA-2 submillimeter and archival SPIRE far-infrared imaging of a z = 1.62 cluster, Cl 0218.3–0510, which lies in the UKIRT Infrared Deep Sky Survey/Ultra-Deep Survey field of the SCUBA-2 Cosmology Legacy Survey. Combining these tracers of obscured star-formation activity with the extensive photometric and spectroscopic information available for this field, we identify 31 far-infrared/submillimeter-detected probable cluster members with bolometric luminosities 1012 L ☉ and show that by virtue of their dust content and activity, these represent some of the reddest and brightest galaxies in this structure. We exploit ALMA submillimeter continuum observations, which cover one of these sources, to confirm the identification of a SCUBA-2-detected ultraluminous star-forming galaxy in this structure. Integrating the total star-formation activity in the central region of the structure, we estimate that it is an order of magnitude higher (in a mass-normalized sense) than clusters at z ~ 0.5-1. However, we also find that the most active cluster members do not reside in the densest regions of the structure, which instead host a population of passive and massive, red galaxies. We suggest that while the passive and active populations have comparable near-infrared luminosities at z = 1.6, MH ~ –23, the subsequent stronger fading of the more active galaxies means that they will evolve into passive systems at the present day that are less luminous than the descendants of those galaxies that were already passive at z ~ 1.6 (MH ~ –20.5 and MH ~ –21.5, respectively, at z ~ 0). We conclude that the massive galaxy population in the dense cores of present-day clusters were already in place at z = 1.6 and that in Cl 0218.3–0510 we are seeing continuing infall of less extreme, but still ultraluminous, star-forming galaxies onto a pre-existing structure
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV
The Lambda(b) differential production cross section and the cross section
ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum
pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7
TeV using data collected by the CMS experiment at the LHC. The measurements are
based on Lambda(b) decays reconstructed in the exclusive final state J/Psi
Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and
Lambda to proton pion, using a data sample corresponding to an integrated
luminosity of 1.9 inverse femtobarns. The product of the cross section times
the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls
faster than that of b mesons. The measured value of the cross section times the
branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06
+/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for
anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are
statistical and systematic, respectively.Comment: Submitted to Physics Letters
Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV
A search is presented for physics beyond the standard model (BSM) in final
states with a pair of opposite-sign isolated leptons accompanied by jets and
missing transverse energy. The search uses LHC data recorded at a
center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to
an integrated luminosity of approximately 5 inverse femtobarns. Two
complementary search strategies are employed. The first probes models with a
specific dilepton production mechanism that leads to a characteristic kinematic
edge in the dilepton mass distribution. The second strategy probes models of
dilepton production with heavy, colored objects that decay to final states
including invisible particles, leading to very large hadronic activity and
missing transverse energy. No evidence for an event yield in excess of the
standard model expectations is found. Upper limits on the BSM contributions to
the signal regions are deduced from the results, which are used to exclude a
region of the parameter space of the constrained minimal supersymmetric
extension of the standard model. Additional information related to detector
efficiencies and response is provided to allow testing specific models of BSM
physics not considered in this paper.Comment: Replaced with published version. Added journal reference and DO
Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV
Isolated photon production is measured in proton-proton and lead-lead
collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the
pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80
GeV with the CMS detector at the LHC. The measured ET spectra are found to be
in good agreement with next-to-leading-order perturbative QCD predictions. The
ratio of PbPb to pp isolated photon ET-differential yields, scaled by the
number of incoherent nucleon-nucleon collisions, is consistent with unity for
all PbPb reaction centralities.Comment: Submitted to Physics Letters
A study of single and multi-photon production in collisions at centre-of mass energies of 130 and 136 GeV
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