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Objective The aim of this study was to assess pharmacists' knowledge about the safe use of topical corticosteroids (TCS) in the treatment of atopic dermatitis (AD) and to determine whether their knowledge and beliefs can be modified after reading the designed module on TCS use in AD. Methods A multicentre cross-sectional survey study was conducted among pharmacists working in the healthcare facilities of Malaysia between February 2018 and April 2019. A total of 310 pharmacists were participated and requested to complete the questionnaire before (pre-test) and 1 week after reading the designed TCS module (post-test). Results Pharmacist's post-module score [median = 8 (interquartile range {IQR} 5–11)] was significantly higher than their pre-module score [median = 5 (IQR1–10; P < 0.001)]. After reading the TCS module, there was a significant increase in correct responses observed to the dispensing activities, application recommendations and side effects associated with the inappropriate use of TCS (P < 0.001). Pharmacists were found highly confident in the use of TCS after reading the designed module with a mean score of 8.0 (95% confidence interval 7.87–8.13) out of 10 measured on the Likert scale. Conclusion TCS module has been proven effective in enhancing pharmacists' knowledge about the safe use of TCS in the treatment of AD. [ABSTRACT FROM AUTHOR]

High-pressure torsion (HPT) is an established material strengthening technique through severe plastic deformation. Expanding its strengthening capabilities requires an appropriate deformation control. Unlike the thoroughly reviewed associated strengthening parameters like sample and processing variables, limited information concerning the apparatus variables is available due to the high experimental cost. This limitation was addressed in this present work by conducting parametric analysis through finite element simulation. This study examined the effects of anvil parameters, including the free flow gap between anvils, anvil wall inclination angle and anvils alignment, on the stress characteristics during HPT. The systematic analysis revealed that the free flow gap, j of 1 mm, leads to a heterogeneous pressure distribution across the sample radius. However, the pressure homogeneity depends slightly on the wall inclination angle, β . In particular, j ≤ 0.2 mm and β ≤ 10° could generate continuous strengthening behaviour with the applied strain. Furthermore, misalignment also demonstrated contributing to the disc centre strengthening, a critical explanation that the fundamental torsion test formula could not describe. The presented parametric analysis through a computer-aided numerical computation serves as an effective deformation control and optimisation. It complements the existing theory and experimental findings at a minimal computation cost. [ABSTRACT FROM AUTHOR]

This document is a reference list for a research paper on fracture mechanics and structural integrity. The paper explores the effect of element size on fracture propagation stress using energy criteria. The research was funded by the Ministry of Higher Education Malaysia. The document also includes a Python code for an artificial neural network algorithm used in the research. The reference list contains other research papers on fracture mechanics, machine learning, and structural integrity. [Extracted from the article]

A review of nonlocal theories utilized in the fatigue and fracture modeling of solid structures is addressed in this paper. Numerous papers have been studied for this purpose, and various nonlocal theories such as the nonlocal continuum damage model, stress field intensity model, peridynamics model, elastic-plastic models, energy-based model, nonlocal multiscale model, microstructural sensitive model, nonlocal lattice particle model, nonlocal high cycle fatigue model, low cycle fatigue model, nonlocal and gradient fracture criteria, nonlocal coupled damage plasticity model and nonlocal fracture criterion have been reviewed and summarized in the case of fatigue and fracture of solid structures and materials. [ABSTRACT FROM AUTHOR]

This paper presents a durability analysis of two types of copper leadframe, i.e. the un-oxidised leadframe and the oxidised leadframe. Both leadframe types were used in the fabrication process of a Quad Flat No-Lead (QFN) package, which can be said as a recent type of the 3D stacked die semiconductor package. This study involved the durability test and analysis on QFN packages when these packages were subjected under constant cyclic loadings. In order to perform the cyclic test, the procedure of the three-point cyclic bending test has been employed on the packages. In addition, a strain gauge which was connected to the dynamic data acquisition system was used for each tested QFN package for determining the response of the captured cyclic strain signal. It has been found that the variable amplitude pattern of signal response has been obtained during the constant cyclic test. The obtained response signals for both type of leadframe were then analysed using the approaches of signal processing technique, which is relatively new in this field. The collected response signal were analysed using the normal statistical methods, the Power Spectrum Density (PSD) calculation and also the time-frequency localization analysis. From the detail signal analysis, it has been found that the un-oxidised leadframe showed a lower range of strain response compared to the oxidised leadframe, indicating higher lifetime. As a result, this finding lead to the durability conclusion, for which the un-oxidised leadframe has more durability effects and it also has higher lifetime compared to the oxidised leadframe. Finally, a micro-crack phenomenon at the epoxy interface between the die and the leadframe was also observed for the QFN package with the oxidised leadframe. [ABSTRACT FROM AUTHOR]

The aim of this paper is to characterise the fatigue reliability for various random strain loads under extreme value distribution while considering the cycle sequence effect condition in fatigue life prediction. The established strain–life models, i.e., Morrow and Smith–Watson–Topper, considered a mean stress effect and strain amplitude; nevertheless, it excluded the load sequence effect, which involves the fatigue crack closure that is subjected to overload or underload. A FESEM-EDX analysis is conducted to characterise the failure features that occurred on the leaf spring. A finite element is simulated to determine the critical region in order to obtain the strain load behaviour. In addition, the strain signal is captured experimentally at 500 Hz for 100 s under operating conditions for three different road loads based on the critical location obtained from the finite element analysis. The fatigue life correlation shows that the Pearson correlation coefficients are greater than 0.9, which indicates the effective strain damage model is linearly correlated with the strain–life models. The fatigue life data are modelled using extreme value distribution by considering the random strain loads as extreme data. The reliability rate for the fatigue life is reported to be more than 0.59 within the hazard rate range of 9.6 × 10−8 to 1.2 × 10−7 based on the mean cycle to the failure point. Hence, the effective strain damage model is proposed for a fatigue reliability assessment under extreme conditions with higher reliability and provides fatigue life prediction when subjected to cycle sequence effects. [ABSTRACT FROM AUTHOR]

The factors that are normally considered by customers for comfortable driving upon purchasing a car are acoustical comfort and exposed vibration. Keeping this in mind, the level of noise annoyance in reference to the vehicle acoustical comfort index is proposed. This index can be categorized by five states which are generally used in the computation that involve acoustical levels in the car cabin. This study is carried out in order to improve this index by classifying and categorizing these five states using the fuzzy set theory approach. Besides, identified sources of vibration are usually linked with engine transmission and tire-road interaction. This study includes the observation on the effects of the vibration due to tire interaction with the road, as well as the pattern of the trends toward the experienced noise against the engine speed [rpm] at both stationary and non-stationary positions. A combination of fuzzy set theory and nonlinear programming has been employed to develop a multi-objective model of hybrid fuzzy nonlinear weighted goal programming. This developed model adopts the results that have been provided in order to optimize the acoustics level by referring to the vibration level which is required at a certain value of the engine speed [rpm]. The proposed model has a significant impact towards a better environment, in the perspective of acoustics – a key factor in vehicle manufacturing process. [ABSTRACT FROM AUTHOR]

One of the characteristics that may influence customers in vehicle purchasing is the level of comfort of the vehicle’s sound vibration in the vehicle cabin. The basic principle suggests that the sound vibration discomfort level is affected by a few factors which are mainly based on magnitudes, frequencies, directions and also the exposed periods. Normally, the phenomenon of sound vibration disrupts the performance of the driver by affecting the driver’s vision and also inducing a certain degree of stress due to the sound and vibration to which the driver and his or her passengers are exposed. The sound vibration is generally contributed by a few sources originated from the transmission of the vehicle’s engine, tire interactions with the road surface and also the exposure of vehicle’s body vibration during the movement. The objective of this study is to propose an approach that clusters the level of sound and vibration into a few categories and classifies them into those categories without implementing the subjective test that normally involves human assessment. The study has observed the changes of the sound quality and the level of vibration at particular points in the vehicle cabin over the changes of engine speeds. In reference to the results, the study has successfully provided a technical procedure in order to cluster, and also to classify, the level of sound vibration by taking into account the correlation between experienced noise and exposed vibration in the vehicle cabin. [ABSTRACT FROM AUTHOR]

Vehicle vibration and acoustical comfort are crucial criteria which may attract customers when purchasing a vehicle. This phenomenon will influence the performance of the drivers in a way that it will distract their vision which can be stressful to both the driver and passengers. Two identified main sources that contribute to the generation of vibration are the transmission of the engine and also the tire and road contact while the car is being driven. As we take into account the factor of tire-road contact, we investigate the correlation that exists between the sound quality from the noise and the changes of the exposed vibration at particular parts in the cabin. Here the trend?s significance levels will be obtained by performing data analysis towards the factor of sound and vibration. Through the results, we have found that the exposed vibration influences the generation of noise that is linked with the level of acoustical comfort in the cabin. At the end of the study, a model of evaluation method on the experienced sound and exposed vibration was successfully proposed using the clustering and classification method. [ABSTRACT FROM AUTHOR]

Noise has various effects on comfort, performance and health of human. Sound are analysed by human brain based on the frequencies and amplitudes. In a dynamic system, transmission of sound and vibrations depend on frequency and direction of the input motion and characteristics of the output. It is imperative that automotive manufacturers invest a lot of effort and money to improve and enhance the vibro-acoustics performance of their products. The enhancement effort may be very difficult and time-consuming if one relies only on ‘trial and error’ method without prior knowledge about the sources itself. Complex noise inside a vehicle cabin originated from various sources and travel through many pathways. First stage of sound quality refinement is to find the source. It is vital for automotive engineers to identify the dominant noise sources such as engine noise, exhaust noise and noise due to vibration transmission inside of vehicle. The purpose of this paper is to find the vibro-acoustical sources of noise in a passenger vehicle compartment. The implementation of spectral analysis method is much faster than the ‘trial and error’ methods in which, parts should be separated to measure the transfer functions. Also by using spectral analysis method, signals can be recorded in real operational conditions which conduce to more consistent results. A multi-channel analyser is utilised to measure and record the vibro-acoustical signals. Computational algorithms are also employed to identify contribution of various sources towards the measured interior signal. These achievements can be utilised to detect, control and optimise interior noise performance of road transport vehicles. [Copyright &y& Elsevier]

This study characterized the properties of random strain loading data for using power spectral density (PSD) in frequency domain of a heavy vehicle leaf spring. This is due to missing data caused by the sensitivity of the strain gauges in capturing strain signal. Strain signal was captured from a leaf spring component for 100 s at a sampling rate of 200 Hz using strain gauge. Fatigue life prediction was computed using strain-life models: Coffin-Manson, Morrow and Smith-Watson-Topper (SWT). The fatigue strain data showed that downhill data produces the lowest fatigue life prediction at 3.42 × 102 cycles/block with high energy of 3.6 × 104μɛ2.Hz-1; then it was followed by curve and highway data. This was supported by the root-mean-square (RMS) value at 324.24 μɛ as it is directly related towards the PSD based on the energy contained for each captured signal. The correlation of fatigue life and strain amplitude was calculated to identify the distribution of fatigue strain data of leaf spring. Thus, the fatigue strain loading data can be characterized properly based on the energy content in PSD, the statistical parameter in the form of RMS value and the correlation with strain amplitude for random strain loading of leaf spring. [ABSTRACT FROM AUTHOR]

In this study, analytical and computational analysis is performed to determine the effect of thermodynamic detonation parameters on the performance of the pulse detonation engine. For analytical study along with pure fuels blend of hydrogen (50 %) + kerosene (50 %), hydrogen (50 %) + methane (50 %) and methane (50 %) + kerosene (50 %) are considered. The ANSYS FLUENT program is utilized two-dimensional computational fluid dynamics (CFD) simulation using a stoichiometric mixture of three pure fuels: hydrogen-air, methane-air, and kerosene-air. Time-dependent numerical simulations are used to explore the flow condition inside the detonation tube. Excellent performance is observed for hydrogen-air fuel. Hydrogen shows the highest velocity of 2524.36 m/s and a specific impulse of 6842.16 s. The lowest velocity and specific impulse are produced by kerosene of 1520 m/s and 1473.6 s, respectively. It is shown that measured parameters could vary significantly depending on the choice of fuels used. The results infer that hydrogen blends of methane and kerosene fuels are also suitable for pulse detonation engine (PDE) application. Finally, these analytical and simulated results are validated with the previously published literature and NASA CEA (national aeronautics and space administration -chemical equilibrium with applications). • Analytical & CFD studies are conducted to analyse the effect of fuels on PDE. • Effect of fuels on performance of pulse detonation tube are investigated. • Combustion ingredients involving basic light molecules easier to detonate. • Alternative & blended fuels are recommended for PDE along with hydrogen fuel. [ABSTRACT FROM AUTHOR]

Abstract: Sound quality is among the main factors that influence customers’ preference for choosing good automobile products. It all started more than 10 years ago and grows up so fast due to high competition in the automotive industries. A-weighted noise levels and sound power are usually utilised to measure the noise but they are not adequate to characterise the impact sound inside a car. The most popular approach to determine sound quality of a product is to define an annoyance or specific index, which involves both subjective and objective evaluations. Subjective and objective tests should be studied concurrently in order to determine the sound quality inside a passenger car. This approach is used in this paper to evaluate vehicle comfort index according to most frequently used sound quality metrics, namely; Zwicker loudness, sharpness, roughness and fluctuation strength. As a result researchers of different fields of automotive acoustics investigations can use this index according to the type of road (international road roughness) without any need to perform time-consuming jury tests. The metrics are correlated with jury test results that show which of them and how much has affected the acoustical comfort of the vehicle. The relation between road roughness and vehicle acoustical comfort index is another point of interest in this research. [Copyright &y& Elsevier]