Predicting Noise-Induced Hearing Loss (NIHL) and Hearing Deterioration Index (HDI) in Malaysian Industrial Workers using GDAM Algorithm

Noise is a form of a pollutant that is terrorizing the occupational health experts for many decades due to its adverse side-effects on the workers in the industry. Noise-Induced Hearing Loss (NIHL) handicap is one out of many health hazards caused due to excessive exposure to high frequency noise emitted from the machines. A number of studies have been carried-out to find the significant factors involved in causing NIHL in industrial workers using Artificial Neural Networks. Despite providing useful information on hearing loss, these studies have neglected some important factors.  Therefore, the current study is using age, work-duration, and maximum and minimum noise exposure as the main factors involved in the hearing loss. Gradient Descent with Adaptive Momentum (GDAM) algorithm is proposed to predict the NIHL in workers. The results show 98.21% average accuracy between the actual and the predicted datasets and the MSE for both ears is 2.10x10-3. Hearing threshold shift found in the selected workers was greater than 25 dB, which means hearing impairment has occurred. Also, Hearing Deterioration Index (HDI) is found to be quite high for different sound pressure levels such as maximum exposure (dB) and average exposure (dB) but is reported normal for minimum exposure (dB) for all workers. 

Comparative air conditioning performance using SiO2 and Al2O3 nanolubricants operating with Hydrofluoroolefin-1234yf refrigerant

Nowadays, the automotive air-conditioning system operating with Hydrofluoroolefin-1234yf or R1234yf refrigerant is used to reduce the global warming potential. This study aims to investigate the performance of SiO2 and Al2O3 nanolubricants with R1234yf refrigerant in the automotive air conditioning system. The polyalkylene glycol-based nanolubricant was prepared using a two-step preparation method, and the stability of the nanolubricant was assessed using visual sedimentation observation and zeta potential analysis. The experimental investigation on the performance of automotive air conditioning system with R1234yf was undertaken for the SiO2 and Al2O3 nanolubricants at different volume concentrations and various operating conditions. The system with SiO2 nanolubricant at 0.01% volume concentration demonstrated the best cooling capacity performance with an average enhancement of 15.7%. On the other hand, the highest coefficient of performance increment and power consumption reduction were attained up to 9.8% and 27.1%, respectively for Al2O3 nanolubricant at 0.05% volume concentration. The SiO2 nanolubricant performed with better cooling capacity, higher power consumption and lower coefficient of performance than the polyalkylene glycol-based lubricant. In contrast, the Al2O3 nanolubricant improved the coefficient of performance and reduced the power consumption. Since both nanolubricants provide their respective advantages, more research into integrating the two nanoparticles for refrigeration systems with R1234yf refrigerant is encouraged

Position Tracking Optimization for An Electro-hydraulic Actuator System

Electro-hydraulic actuator (EHA) system has received a positive admission and widely utilized in the industrial field for the process such as lifting, clamping and pressing. It is well known that the EHA system is exposed to the disturbances, uncertainties, and parameter variations which are caused by various factors for instance the changes in load or total moving mass, supply pressure, friction and leakage coefficient. These problems consequently pose to a great challenge in EHA system modelling and controller development in order to achieve a good performance in the system positioning control. In this paper, a comparative study in different trajectories that represents the desired positioning which are multi-step and multi-sine reference signal is applied to the system in order to access the capability of the proportional-integral-derivative (PID) controller that is tuned by using the Ziegler-Nichols (ZN) and Particle Swarm Optimization (PSO) tuning methods. The finding shows that the PID controller variables obtained through the PSO tuning method performs better than the conventional ZN tuning method. From the simulation study, it can be concluded that the PSO technique was able to obtain a better PID controller parameter and provides a much satisfying positioning tracking capabilit

Case report: Unusual cause of difficulty in intubation and ventilation with asthmatic-like presentation of Endobronchial Tuberculosis

Endobronchial Tuberculosis is hazardous in causing circumferential narrowing of tracheobronchial tree despite the eradication of tubercle bacilli in the initial insult from Pulmonary Tuberculosis. They may present as treatment resistant bronchial asthma and pose challenge to airway management in the acute setting. We present a 25 year-old lady who was newly diagnosed bronchial asthma with a past history of Pulmonary Tuberculosis that had completed treatment. She presented with sudden onset of difficulty breathing associated with noisy breathing for 3 days and hoarseness of voice for 6 months. Due to resistant bronchospasm, attempts were made to secure the airway which led to unanticipated difficult intubation and ventilation. Subsequent investigations confirmed the diagnosis of Endobronchial Tuberculosis and patient was managed successfully with anti TB medication, corticosteroids and multiple sessions of tracheal dilatation for tracheal stenosis. This case highlights the unusual cause of difficulty in intubation and ventilation due to Endobronchial Tuberculosis, which required medical and surgical intervention to improve the condition

Search for the Zγ decay mode of new high-mass resonances in pp collisions at √s = 13 TeV with the ATLAS detector

This letter presents a search for narrow, high-mass resonances in the Zγ final state with the Z boson decaying into a pair of electrons or muons. The √s = 13 TeV pp collision data were recorded by the ATLAS detector at the CERN Large Hadron Collider and have an integrated luminosity of 140 fb−1. The data are found to be in agreement with the Standard Model background expectation. Upper limits are set on the resonance production cross section times the decay branching ratio into Zγ. For spin-0 resonances produced via gluon–gluon fusion, the observed limits at 95% confidence level vary between 65.5 fb and 0.6 fb, while for spin-2 resonances produced via gluon–gluon fusion (or quark–antiquark initial states) limits vary between 77.4 (76.1) fb and 0.6 (0.5) fb, for the mass range from 220 GeV to 3400 GeV

Searches for exclusive Higgs boson decays into D⁎γ and Z boson decays into D0γ and Ks0γ in pp collisions at √s = 13 TeV with the ATLAS detector

Searches for exclusive decays of the Higgs boson into D⁎γ and of the Z boson into D0γ and Ks0γ can probe flavour-violating Higgs boson and Z boson couplings to light quarks. Searches for these decays are performed with a pp collision data sample corresponding to an integrated luminosity of 136.3 fb−1 collected at s=13TeV between 2016–2018 with the ATLAS detector at the CERN Large Hadron Collider. In the D⁎γ and D0γ channels, the observed (expected) 95% confidence-level upper limits on the respective branching fractions are B(H→D⁎γ)<1.0(1.2)×10−3, B(Z→D0γ)<4.0(3.4)×10−6, while the corresponding results in the Ks0γ channel are B(Z→Ks0γ)<3.1(3.0)×10−6

The ATLAS trigger system for LHC Run 3 and trigger performance in 2022

The ATLAS trigger system is a crucial component of the ATLAS experiment at the LHC. It is responsible for selecting events in line with the ATLAS physics programme. This paper presents an overview of the changes to the trigger and data acquisition system during the second long shutdown of the LHC, and shows the performance of the trigger system and its components in the proton-proton collisions during the 2022 commissioning period as well as its expected performance in proton-proton and heavy-ion collisions for the remainder of the third LHC data-taking period (2022–2025)

Combination of searches for heavy spin-1 resonances using 139 fb−1 of proton-proton collision data at √s = 13 TeV with the ATLAS detector

A combination of searches for new heavy spin-1 resonances decaying into diferent pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fb−1 of proton-proton collisions at √s = 13 TeV collected during 2015–2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb, tt¯, and tb) or third-generation leptons (τν and τ τ ) are included in this kind of combination for the frst time. A simplifed model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confdence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion

Search for a new heavy scalar particle decaying into a Higgs boson and a new scalar singlet in final states with one or two light leptons and a pair of τ-leptons with the ATLAS detector

A search for a new heavy scalar particle X decaying into a Standard Model (SM) Higgs boson and a new singlet scalar particle S is presented. The search uses a proton-proton (pp) collision data sample with an integrated luminosity of 140 fb−1 recorded at a centre-of-mass energy of s√ = 13 TeV with the ATLAS detector at the Large Hadron Collider. The most sensitive mass parameter space is explored in X mass ranging from 500 to 1500 GeV, with the corresponding S mass in the range 200–500 GeV. The search selects events with two hadronically decaying τ-lepton candidates from H → τ+τ− decays and one or two light leptons (ℓ = e, μ) from S → VV (V = W, Z) decays while the remaining V boson decays hadronically or to neutrinos. A multivariate discriminant based on event kinematics is used to separate the signal from the background. No excess is observed beyond the expected SM background and 95% confidence level upper limits between 72 fb and 542 fb are derived on the cross-section σ(pp → X → SH) assuming the same SM-Higgs boson-like decay branching ratios for the S → VV decay. Upper limits on the visible cross-sections σ(pp → X → SH → WWττ) and σ(pp → X → SH → ZZττ) are also set in the ranges 3–26 fb and 6–33 fb, respectively

Measurement of the cross-sections of the electroweak and total production of a Zγ pair in association with two jets in pp collisions at √s = 13 TeV with the ATLAS detector

This Letter presents the measurement of the fiducial and differential cross-sections of the electroweak production of a Zγ pair in association with two jets. The analysis uses 140 fb−1 of LHC proton–proton collision data taken at √s = 13 TeV recorded by the ATLAS detector during the years 2015–2018. Events with a Z boson candidate decaying into either an e+e− or μ+μ− pair, a photon and two jets are selected. The electroweak component is extracted by requiring a large dijet invariant mass and by using the information about the centrality of the system and is measured with an observed and expected significance well above five standard deviations. The fiducial pp → Zγ jj cross-section for the electroweak production is measured to be 3.6 ± 0.5 fb. The total fiducial cross-section that also includes contributions where the jets arise from strong interactions is measured to be 16.8+2.0 −1.8 fb. The results are consistent with the Standard Model predictions. Differential cross-sections are also measured using the same events and are compared with parton-shower Monte Carlo simulations. Good agreement is observed between data and predictions