23 research outputs found

    ASSESSMENT OF THE QUADRUPLE INJECTION STRATEGY OVER TRIPLE INJECTIONS TO IMPROVE EMISSIONS, PERFORMANCE AND NOISE OF THE AUTOMOTIVE DIESEL ENGINE

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    The present study aims at investigating effectiveness of the quadruple (early-pilot-main-after [epMa]) injection strategy over three different triple [early-main-after (eMa), early-pilot-main (epM) and pilot-main-after (pMa)] injection scheduling in terms of emissions, performance [brake specific fuel consumption (BSFC), torque, brake thermal efficiency (BTE) and fuel economy] and noise. The experimentation was carried out on a heavy-duty BS-IV diesel engine with 45% EGR fraction and fixed main injection (Crank-angle) scheduling at eight different RPMs and three loads of engine (20%, 60% and 100%) using design of experiments(DOE).     This comprehensive study showed that the quadruple injection strategy provides optimum results in both performance and emissions compared to the promising three triple injection strategy. The quadruple injection strategy exhibits the best BTE at all operating conditions and best BSFC at medium to high-speed zone around 0.5–1% inline to reduce combustion noise (CN) level, especially at low speeds and low to medium load of 0.2–2.2 dBA. Among triple injections, the pMa shows the best performance in BSFC, BTE, smoke and THC emissions. The epM is the best in the CO emissions and torque performance in the low-speed zone. Smoke value is marginally higher for the epMa at low to medium speed than the pMa, although average smoke emissions were the best. Taken together, the overall PM emission level was marginally better than Triple Injections, due to the impact of double pilots in combination with post-injection. In addition, NOx emissions were improved (around 3–6%) significantly with quadruple than with triple injections. The epMa injection scheduling also showed improvement in constant speed fuel economy and in pass-by-noise at the vehicle

    Comparative Study of Power, Delay and Noise of Logic Gates between CMOS and GaAs MESFET

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    Abstract: This Gallium Arsenide MESFET based an absolutely new model of universal gates has been designed, analysed, reviewed & compared. Overall the newly designed model is fed by physical inputs which are highly researched and developed several times. This model is capable to remove all the difficulties of previously proposed and designed models. The necessity of implementing this type of structure is to encounter absence of dielectric in the CMOS structur

    Lanthanum halide nanoparticle scintillators for nuclear radiation detection

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    Nanoparticles with sizesscintillators, in order to determine the viability of using scintillators employing nanostructured lanthanum trifluoride. Preliminary results of this investigation are consistent with the idea that these materials have an intrinsic response to nuclear radiation that may be correlated to the energy of the incident radiation

    Report from Working Group 3: Beyond the standard model physics at the HL-LHC and HE-LHC

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    This is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as 33 ab1^{-1} of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as 1515 ab1^{-1} of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by 2050%20-50\% on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics

    Field Deployable Gamma Radiation Detectors for DHS Use

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    ABSTRACT Recently, the Department of Homeland Security (DHS) has integrated all nuclear detection research, development, testing, evaluation, acquisition, and operational support into a single office: the Domestic Nuclear Detection Office (DNDO). The DNDO has specific requirements set for all commercial off-the-shelf and government off-the-shelf radiation detection equipment and data acquisition systems. This article would investigate several recent developments in field deployable gamma radiation detectors that are attempting to meet the DNDO specifications. Commercially available, transportable, handheld radio isotope identification devices (RIID) are inadequate for DHS' requirements in terms of sensitivity, resolution, response time, and reach-back capability. The leading commercial vendor manufacturing handheld gamma spectrometer in the United States is Thermo Electron Corporation. Thermo Electron's identiFINDER™, which primarily uses sodium iodide crystals (3.18 x 2.54cm cylinders) as gamma detectors, has a Full-Width-at-Half-Maximum energy resolution of 7 percent at 662 keV. Thermo Electron has just recently come up with a reach-back capability patented as RadReachBack™ that enables emergency personnel to obtain real-time technical analysis of radiation samples they find in the field 1 . The current project has the goal to build a prototype handheld gamma spectrometer, equipped with a digital camera and an embedded cell phone to be used as an RIID with higher sensitivity, better resolution, and faster response time (able to detect the presence of gamma-emitting radio isotopes within 5 seconds of approach), which will make it useful as a field deployable tool. The handheld equipment continuously monitors the ambient gamma radiation, and, if it comes across any radiation anomalies with higher than normal gamma gross counts, it sets an alarm condition. When a substantial alarm level is reached, the system automatically triggers the saving of relevant spectral data and software-triggers the digital camera to take a snapshot. The spectral data including in situ analysis and the imagery data will be packaged in a suitable format and sent to a command post using an imbedded cell phone
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