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The reliable transcranial imaging of brain inner structures for diagnostic purposes is deemed crucial owing to the decisive importance and contribution of the brain in human life. The purpose of this paper is to investigate the potential application of medical ultrasounds to transcranial imaging using advanced techniques, such as the total focussing method.

Initially, the fundamental details of the total focussing method are presented, while the skull properties, such as the increased acoustic velocity and scattering, are thoroughly examined. Although, these skull characteristics constitute the main drawback of typical transcranial ultrasonic propagation algorithms, they are exploited to focus the acoustic waves towards the brain. To this goal, a virtual source is designed, considering the wave refraction, to efficiently correct the reconstructed brain image. Finally, the verification of the novel method is conducted through numerical simulations of various realistic setups.

The theoretically designed virtual source resembles a focussed sensor; therefore, the directivity increment, owing to the propagation through the skull, is confirmed. Moreover, numerical simulations of real-world scenarios indicate that the typical artifacts of the conventional total focussing method are fully overcome because of the increased directivity of the proposed technique, while the reconstructed image is efficiently corrected when the proposed virtual source is used.

A new systematic methodology along with the design of a flexible virtual source is developed in this paper for the reliable and precise transcranial ultrasonic image reconstruction of the brain. Despite the slight degradation owing to the skull scattering, the combined application of the total focussing method and the featured virtual source can successfully detect arbitrary anomalies in the brain that cannot be spotted by conventional techniques.

Survey research of top managers is critical to addressing many contemporary research questions in the field of strategic management. Yet, the threat of low response rates has discouraged many researchers from attempting this type of work, steering the field of strategic management away from issues related to strategic process. This article provides an empirical examination of factors that determine the likelihood and quality of response to top management surveys. More generally, we advance a theoretical perspective on survey response rooted in social influence theory that should help researchers make better choices about the design of their survey questionnaires.

Despite the perfect nutritional value of imperfect “ugly” produce, they are either never harvested or discarded, resulting in escalating farm-to-fork food waste problems in the USA. The purpose of this paper is to investigate US consumers’ perceptions of imperfect “ugly” produce and their willingness to purchase and consume these foods in their households.

Four focus group sessions with at least five voluntary participants per session were conducted. Each session used structured interview questions and the discussions were led by the same moderator. All sessions were recorded, transcribed and analyzed based on published focus group guidelines and recommendations.

The research study has revealed two categories of potential consumers, Influencers and Learners, when it comes to an initial understanding of “ugly” produce consumption. The study also identified nine themes (i.e. food safety, price sensitivity, location of sale, product display, name/label, purpose of use, fun, targeted education and food waste) that consumers hold regarding imperfect “ugly” produce.

Insights from this study provide strategies for sustainable food management that could help stakeholders along all points of the food chain save money, reduce hunger and diminish food waste in our communities.

This study serves to provide preliminary insights in approaching the issue of consumers’ perception of imperfect “ugly” fruits and vegetables from a research perspective. Although a limited number of real consumers from the local community participated, their rich and in-depth qualitative responses defined the scope and the defining questions that need further exploration.

This paper aims to propose a new ultrasonic diagnosis method for stainless steel weld defects based on multi-domain feature fusion to solve two problems in the ultrasonic diagnosis of austenitic stainless steel weld defects. These are insufficient feature extraction and subjective dependence of diagnosis model parameters.

To express the richness of the one-dimensional (1D) signal information, the 1D ultrasonic testing signal was derived to the two-dimensional (2D) time-frequency domain. Multi-scale depthwise separable convolution was also designed to optimize the MobileNetV3 network to obtain deep convolution feature information under different receptive fields. At the same time, the time/frequent-domain feature extraction of the defect signals was carried out based on statistical analysis. The defect sensitive features were screened out through visual analysis, and the defect feature set was constructed by cascading fusion with deep convolution feature information. To improve the adaptability and generalization of the diagnostic model, the authors designed and carried out research on the hyperparameter self-optimization of the diagnostic model based on the sparrow search strategy and constructed the optimal hyperparameter combination of the model. Finally, the performance of the ultrasonic diagnosis of stainless steel weld defects was improved comprehensively through the multi-domain feature characterization model of the defect data and diagnosis optimization model.

The experimental results show that the diagnostic accuracy of the lightweight diagnosis model constructed in this paper can reach 96.55% for the five types of stainless steel weld defects, including cracks, porosity, inclusion, lack of fusion and incomplete penetration. These can meet the needs of practical engineering applications.

This method provides a theoretical basis and technical reference for developing and applying intelligent, efficient and accurate ultrasonic defect diagnosis technology.

The purpose of this paper is to investigate cotton fabric behavior that is exposed to radar waves between selected operation frequencies as an alternative radar-absorbing material (RAM) response. Cotton fabric biocomposite materials were compared with carbon fabric composite materials, which are good absorbers, in terms of mechanical and electromagnetic (EM) properties for that purpose.

The laminated composite plates were manufactured by using a vacuum infusion process. The EM tests were experimentally performed with a vector network analyzer to measure reflection, transmission and absorption ability of cotton fabric, carbon fabric and cotton–carbon fabric (side by side) composite plates between 3 and 18 GHz. The tensile and low-velocity impact tests were carried out to compare the mechanical properties of cotton fabric and carbon fabric composite plates. A scanning electron microscope was used for viewing the topographical features of fracture surfaces.

The cotton fabric composite plate exhibits low mechanical values, but it gives higher EM wave absorption values than the carbon fabric composite plate in certain frequency ranges. Comparing the EM absorption properties of the combination of cotton and carbon composites with those of the carbon composite alone, it appears that the cotton–carbon combination can be considered as a better absorber than the carbon composite in a frequency range from 12 to 18 GHz at Ku band.

This paper shows how cotton, which is a natural and easily supplied low-cost raw material, can be evaluated as a RAM.

The purpose of this paper is to provide comprehensive information on preventive maintenance (PM) planning and methods used in the industry in order to achieve an effective maintenance system.

The literature review is organized in a way that provides the general overview of the researches done in the PM. This paper discusses the literatures that had been reviewed on four main topics, which are the holistic view of maintenance policies, PM planning, PM planning concept and PM planning-based in developing optimal planning in executing PM actions.

PM policy is one of the original proactive techniques that has been used since the start of researches on maintenance system. Review of the methods presented in this paper shows that most researches analyse effectiveness using artificial intelligence, simulation, mathematical formulation, matrix formation, critical analysis and multi-criteria method. While in practice, PM activities were either planned based on cost, time or failure. Research trends on planning and methods for PM show that the variation of approaches used over the year from early 1990s until today.

Research about PM is known to be extensively conducted and majority of companies applied the policy in their production line. However, most analysis and method suggested in published literatures were done based on mathematical computation rather than focussing on solution to real problems in the industry. This normally would lead to the problems in understanding by the practitioner. Therefore, this paper presented researches on PM planning and suggested on the methods that are practical, simple and effective for application in the real industry.

The originality of this paper comes from its detail analysis of PM planning in term of its research focus and also direction for application. Extensive reviews on the methods adopted in relation to PM planning based on the planning-based such as cost-based, time-based and failure-based were also provided.

Consumer expectations of quality have grown in recent years, forcing organisations, both service and manufacturing, to adopt total quality management (TQM) principles to satisfy customer demands efficiently. However, previous studies on the performance impacts of total quality management practices have mainly focused on the financial performance of firms in the manufacturing sector. This study focusses on the research questions: (1) What is the effect of TQM practices on operational performance? and (2) How do TQM practices combine to influence the operational performance of healthcare facilities?

Using a sample of 154 health facilities (i.e. private hospitals, pharmacies, maternity clinics, and diagnostic centres), the authors applied symmetric (PLS-SEM) and asymmetric (fsQCA) data analysis approaches to examine how TQM practices influence the operational performance of health facilities in the Ashanti Region of Ghana.

The PLS-SEM results revealed that five out of the seven TQM practices investigated influenced operational performance. However, the fsQCA results identify five different complex combinations of TQM practices that lead to operational performance.

Longitudinal studies can be conducted in the future to assess changes in the variables over time. A control variable, such as firm size, should be considered to assess the level of implementation of TQM practices based on firm size. A different performance measure, for instance, sustainability indicators or the balance score card, could be used to examine performance.

A proper and coordinated integration of the TQM practices is required for firms to be able to achieve operational performance. TQM practices vary in their sufficiency for operational outcomes; therefore, management needs to carefully consider their implementation as part of the organisation's strategy.

This research, by focussing on TQM practices from both symmetrical and asymmetrical perspectives, contributes to the understanding of the literature on TQM, thereby providing actionable insight on how to invest in the various TQM practices for improved operational performance.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

Increased competition in the banking sector coupled with long queues in the banking hall has necessitated the introduction of internet banking among banks in Ghana. As a result, internet banking has attracted a great deal of attention from both academicians and practitioners. The purpose of this paper is to examine the effect of internet banking on the performance of banking institutions in Ghana.

In total, 20 banks in Ghana were selected from the Bank of Ghana website for the study. The financial information about the banks’ operations was retrieved from the financial statements of the respective banks for the end of the year 2016. The data envelopment analysis-bootstrap approach with principal component analysis and cluster analysis was used to estimate 49 models.

The findings of the study indicated that the integration of internet banking into traditional banking methods has led to superior bank performance in Ghana. It was observed that while the independent application of internet banking as a strategy to raise performance was not yielding higher returns due to the low patronage of internet services among banking consumers, its integration with possible traditional methods is widely observed among the top performers in the banking industry.

Traditional banking methods, integrated banking service strategies and the internet banking service-oriented strategy emerged as the main banking strategies among the banks.

Extant literature is quite silent on the effect of internet banking on bank performance in Africa. However, this paper is among the first significant attempts to examine the effect of internet banking on bank performance.