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This article proposes a relaxed gradient iterative (RGI) algorithm to solve coupled Sylvester-conjugate transpose matrix equations (CSCTME) with two unknowns.

This article proposes a RGI algorithm to solve CSCTME with two unknowns.

The introduced (RGI) algorithm is more efficient than the gradient iterative (GI) algorithm presented in Bayoumi (2014), where the author's method exhibits quick convergence behavior.

The introduced (RGI) algorithm is more efficient than the GI algorithm presented in Bayoumi (2014), where the author's method exhibits quick convergence behavior.

In systems and control, Lyapunov matrix equations, Sylvester matrix equations and other matrix equations are commonly encountered.

In systems and control, Lyapunov matrix equations, Sylvester matrix equations and other matrix equations are commonly encountered.

This article proposes a relaxed gradient iterative (RGI) algorithm to solve coupled Sylvester conjugate transpose matrix equations (CSCTME) with two unknowns. For any initial matrices, a sufficient condition is derived to determine whether the proposed algorithm converges to the exact solution. To demonstrate the effectiveness of the suggested method and to compare it with the gradient-based iterative algorithm proposed in [6] numerical examples are provided.

This work describes the fabrication of composite nanogrease based on carbon nanotubes (CNTs) as an additive at different volume concentrations 0, 0.5, 1, 2 and 3 Wt.% and investigates the correlation between CNTs and grease rheological behaviour. In addition, study the influence of shear thinning rate at various temperatures and investigates the thermal conductivity of nanogrease. The results demonstrated that grease behaves like a Newtonian viscoelastic material with a narrow linear domain. The thermal conductivity of nanogrease was enhanced by about 31.58 per cent, and the thermal and mechanical stabilities improved. Moreover, the apparent viscosity and dropping point increased by about 93 and 27 per cent, respectively.

Grease was dissolved in chloroform (10 Wt.%), at 25°C for 1 h. In parallel, functionalized CNTs with different volume concentrations (0.5, 1, 2 and 3 Wt.%) were dispersed in N,N-dimethylformamide; the dispersion was stirred for 15 min, and then sonicated (40 kHz, 150 W) for 30 min. Grease solution was then added to the CNTs. The nanofluid was magnetically stirred for 15 min and then sonicated for 2 h. This ensured uniform dispersion of nanoparticles in the base fluid.

Inexpensive and simple fabrication of nanogrease. Thermal conductivity of nanogrease was typically enhanced compared to other reported studies. Apparent viscosity and dropping point increases with the increase the volume concentration.

This work describes the inexpensive and simple fabrication of nanogrease for improving properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

To enhance the tribological properties of nanogrease, one of the new technologies was used to synthesize a nanogrease having carbon nanotubes (CNTs) nanoparticles (NPs) with different concentrations. The microstructures of the synthesized NPs were characterized and evaluated by x-ray diffraction spectroscopy (XRD) and transmission electron microscopy (TEM). Tribological properties of the nanogrease were evaluated using a four-ball tester. The worn surface of four steel balls was investigated by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX).

Grease was dissolved in chloroform (10 Wt.%), at 25 °C for 1 h. In parallel, functionalized CNTs with different volume concentrations (0.5, 1, 2 and 3 Wt.%) were dispersed in N, N-dimethylformamide. The mixture was stirred for 15 min and then sonicated (40 kHz, 150 W) for 30 min. After that, the mixture was added to the grease solution and magnetically stirred for 15 min and then sonicated for 2 h.

The results suggested that CNTs can enhance the antiwear and friction properties of nanogrease at 0.5 Wt.% CNTs to about 57 and 48 per cent, respectively. In addition, the weld load of the base oil containing 0.5 Wt.% CNTs was improved by 17 per cent compared with base grease.

This work describes the inexpensive and simple fabrication of nanogrease for improving the properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

The purpose of this paper is to solve the problem of a three-dimensional computational analysis for an elliptic-shaped cavity in a pipe under constant temperature.

The three-dimensional computational solution of governing equations was performed by using finite volume method with different temperature difference.

The parafin wax was chosen as a phase change material (PCM), and melting fraction, streamlines and isotherms are formed for different time step. It is found that position B give better results than that of position A, and temperature difference effects the duration of melting of PCM.

The three-dimensional analysis of melting in an ellipsoidal pipe with inner pipe with higher temperature is the main originality of this work.

The purpose of this paper is to explore the functioning of very‐large‐scale integration (VLSI) interconnects and modeling of interconnects and evaluate different approaches of testing interconnects.

In the past, on‐chip interconnect wires were not considered in circuit analysis except in high precision analysis. Wiring‐up of on‐chip devices takes place through various conductors produced during fabrication process. The shrinking size of metal‐oxide semiconductor field effect transistor devices is largely responsible for growth of VLSI circuits. With deep sub‐micron (DSM) technology, the interconnect geometry is scaled down for high wiring density. The complex geometry of interconnects and high operational frequency introduce wire parasitics and inter‐wire parasitics. These parasitics causes delay, power dissipation, and crosstalk that may affect the signal integrity in VLSI system. Accurate analysis, sophisticated design, and effective test methods are the requirement to ensure the proper functionality and reliability of VLSI circuits. The testing of interconnect is becoming important and a challenge in the current technology.

The effects of interconnect on signal integrity, power dissipation, and delay emerges significantly in DSM technology. For proper performance of the circuit, testing of interconnect is important and emerging challenge in the nanotechnology era. Although some work has been done for testing of interconnect, however, it is still an open area to test the parasitics effects of VLSI/ultra‐large‐scale integration interconnects. Efforts are required to analyze and to develop test methods for crosstalk, delay and power dissipation in current technology with solutions to minimize this effect.

This paper reviews the functioning of VLSI interconnects from micrometer to nanometer technology. The development of various interconnect models from simple short circuit to latest resistance inductance capacitance transmission line model are discussed. Furthermore, various methodologies such as built‐in self test and other techniques for testing interconnect for crosstalk and delay are discussed.

In most conventional pattern recognition methods, the first step is extracting features from objects. These features are always expressed in the form of feature vectors. Then, the distribution of feature vectors is estimated for each category. Finally, an unknown input pattern is assigned to the category with the maximum probability. In this work, we present a system that is able to recognize objects according to the likeness of feature vectors. A database, which consists of images that were identified from a vector of related features, is used by the system to discover these objects. If the resulting image features are compared with the ones included in the database, we obtain the object that has the highest similarity with the one we proposed. The probability of success using our feature vector has been very high.

The purpose of this research paper is to analyze the combined effects of driver size and coupling parasitics on crosstalk noise and delay for static and dynamically switching victim line. Furthermore, this paper shows the effect of inductance on delay and qualitatively optimizes its value to obtain minimum delay.

The interwire parasitics are the primary sources of crosstalk or coupled noise that may lead to critical delays/logic malfunctions. This paper is based on simulating a pair of distributed resistance inductance capacitance (RLC) interconnects coupled capacitively and inductively for measurements of crosstalk noise/delay. The combined effects of driver sizing and interwire parasitics on peak overshoot noise/delay are observed through simulation program with integrated circuit emphasis (SPICE) simulations for different switching patterns. Furthermore, the analysis of inductive effect on propagation delay as a function of coupling capacitance is carried out and the optimization of delay is worked out qualitatively. The simulations are carried out at 0.13 μm, 1.5 V technology node.

This paper observes the contradictory effects of coupling parasitics on wire propagation delay; however, the effect on peak noise is of a different kind. Further, this paper shows that the driver size exhibits opposite kind of behavior on propagation delay than peak over shoot noise. It is observed that the delay is affected in presence of inductance; thus, the optimization of delay is carried out.

The effects of driver sizing and interwire parasitics are analyzed through simulations. The optimum value of coupling capacitance for delay is found qualitatively. These findings are important for designing very large scale integration (VLSI) interconnects.

To investigate wavelet modulus maxima distribution (MMD) in machinery condition monitoring and extract a parameter that can give a quantitative description of machinery‐operating status.

Signal decomposition technique is applied to extract gear motion signal and then wavelet transform modulus maxima are utilized to define fault growth parameter (FGP).

MMD were proposed and the distribution used to derive an EWMA statistic representing machinery fault growth. A comparison with other research works indicates better performance of this parameter.

This paper presents an innovative scheme for the machinery condition monitoring, on the basis of wavelet modulus maxima representation. The definition of MMD can be utilized to derive a parameter that describes the operating status of machinery. This parameter is load‐independent so that it demonstrates better performance when compared with other research works. Further, the MMD may be treated as input of condition classification system in the future work.

The idea for this paper stems from wavelet modulus maxima representation, whilst the application in vibration signal analysis is new. It was found that, by applying this approach, the occurrence of failure is correctly identified and the proposed EWMA FGP is independent of the load applied, which is a very important property in machinery condition monitoring and fault detection.

Service quality in academics is imperatively crucial. Therefore, the purpose of the current research is to examine the effect of academic service quality factors in higher education institutions which mainly focuses on students' satisfaction and the extent of recommending the same institution to other students.

This research evaluated the effect of service quality on student satisfaction and word of mouth (WOM). Data were collected from 200 respondents from various business schools, and hypotheses were tested through a quantitative method using partial least square-structural equation modelling (PLS-SEM) with the help of SmartPLS to validate the measurement model.

The findings of the current research revealed that all three components of service quality including information quality, teaching quality and service efficiency have a significant impact on student satisfaction. Results also indicated that student satisfaction is significantly linked with WOM which means satisfied students spread positive WOM and recommend the same institution to other students.

This research provides an extension towards the body of knowledge on the issue, which will be used in future detailed and critical examinations. The focus of the research was on SERVQUAL and how, when and why business schools may spot possible applications that can have an influence on their admissions by WOM.

Understanding the antecedents of patient safety culture among medical staff is essential if hospital managers are to promote explicit patient safety policies and strategies. The factors that influence patient safety culture have received little attention. The authors aim to investigate the antecedents of patient safety culture (safety climate) in relation to medical staff to develop a comprehensive approach to improve patient safety and the quality of medical care in China.

The Chinese version of the Safety Attitudes Questionnaire (CSAQ) was used to examine the attitudes toward patient safety among physicians and nurses. This medical staff was asked to submit the intra-organizational online survey via email. A total of 1780 questionnaires were issued. The final useable questionnaires were 256, yielding a response rate of 14.38%. One-way analysis of variance (ANOVA) was employed to test if different sex, supervisor/manager, age, working experience, and education result in different perceptions. Confirmatory factor analysis (CFA) was used to verify the structure of the data. Then linear regression with forward selection was performed to obtain the essential dimension(s) that affect the safety culture (safety climate).

The CFA results showed that 26 CSAQ items measured 6 safety-related dimensions. The linear regression results indicated that working conditions, teamwork climate, and job satisfaction had significant positive effects on safety culture (safety climate).

Hospital managers should put increased effort into essential elements of patient-oriented safety culture, such as working conditions, teamwork climate, and job satisfaction to develop appropriate avenues to improve the quality of delivered medical services as well as the safety of patients.

This study focused on the contribution that the antecedents of patient safety culture (safety climate) make with reference to the perspective of medical staff in a tertiary hospital in China.