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The purpose of this study is to experimentally investigate the trends in shock wave Mach number that were observed when different diaphragm material combinations were used in the small-scale shock tube.

A small-scale shock tube was designed and fabricated having a maximum Mach number production capacity to be 1.5 (theoretically). Two microphones attached in the driven section were used to calculate the shock wave Mach number. Preliminary tests were conducted on several materials to obtain the respective bursting pressures to decide the final set of materials along with the layered combinations.

According to the results obtained, 95 GSM tracing paper was seen to be the strongest reinforcing material, followed by 75 GSM royal executive bond paper and regular 70 GSM paper for aluminium foil diaphragms. The quadrupled layered diaphragms revealed a variation in shock Mach number based on the position of the reinforcing material. In quintuple layered combinations, the accuracy of obtaining a specific Mach number was seen to be increasing. Optimization of the combinations based on the production of the shock wave Mach number was carried out.

The shock tube was designed taking maximum incident shock Mach number as 1.5, the experiments conducted were found to achieve a maximum Mach number of 1.437. Thus, an extension to further experiments was avoided considering the factor of safety.

The paper presents a detailed study on the effect of change in the material and its position in the layered diaphragm combinations, which could lead to variation in Mach numbers that are produced. This could be used to obtain a specific Mach number for a required study accurately, with a low-cost setup.

In wireless sensor networks, improving the network lifetime is considered as the prime objective that needs to be significantly addressed during data aggregation. Among the traditional data aggregation techniques, cluster-based dominating set algorithms are identified as more effective in aggregating data through cluster heads. But, the existing cluster-based dominating set algorithms suffer from a major drawback of energy deficiency when a large number of communicating nodes need to collaborate for transferring the aggregated data. Further, due to this reason, the energy of each communicating node is gradually decreased and the network lifetime is also decreased. To increase the lifetime of the network, the proposed algorithm uses two sets: Dominating set and hit set.

The proposed algorithm uses two sets: Dominating set and hit set. The dominating set constructs an unequal clustering, and the hit set minimizes the number of communicating nodes by selecting the optimized cluster head for transferring the aggregated data to the base station. The simulation results also infer that the proposed optimized unequal clustering algorithm (OUCA) is greater in improving the network lifetime to a maximum amount of 22% than the existing cluster head selection approach considered for examination.

In this paper, lifetime of the network is prolonged by constructing an unequal cluster using the dominating set and electing an optimized cluster head using hit set. The dominator set chooses the dominator based on the remaining energy and its node degree of each node. The optimized cluster head is chosen by the hit set to minimize the number of communicating nodes in the network. The proposed algorithm effectively constructs the clusters with a minimum number of communicating nodes using the dominating and hit set. The simulation result confirms that the proposed algorithm prolonging the lifetime of the network efficiently when compared with the existing algorithms.

The proposed algorithm effectively constructs the clusters with a minimum number of communicating nodes using the dominating and hit sets. The simulation result confirms that the proposed algorithm is prolonging the lifetime of the network efficiently when compared with the existing algorithms.

This paper aims to introduce a systematic computing and analytical procedure that is applied to the co-author network to identify the temporal evolution and growth of research collaborations in the area of e-governance. The empirical analysis of the temporal co-author network can trace the emerging authors and knowledge bursts over time.

The study applied social network theory to trace the author collaboration patterns in the domain of e-governance. Analysis of the co-author network using micro and macro parameters was done to trace the temporal evolution of the author collaborations.

E-governance is a multi-disciplinary research domain split over streams of management, politics, information technology and electronics. Hence, research collaborations play a significant role in its advancement. The knowledge sharing between individual authors, institutions and groups through research collaborations, resulting in extensive sharing of data, equipment and research methods, has boosted research activities and development in e-governance. In this paper, the authors systematically analyse the current scenario of research collaborations in the area of e-governance using co-author network to estimate its impact on the advancement of the field. The authors also analysed the temporal evolution of the co-author networks, which show remarkable growth of research collaborations in the domain of e-governance from the year 2000.

The co-author network analysis is only a proxy measure for the analysis of research collaborations. The names of the authors and the university affiliations used in the article are as retrieved from the research repository of Scopus. The degree, citations and other parameters related with authors have scope only within the environment of the co-author network used in the analysis. The criteria used in the study is limited to the degree of research collaborations and the number of co-authored publications in the giant component of the co-author network.

Institutions, authors and governments can trace and select suitable topics and choose research groups of co-authors over the world for future research collaborations in e-governance. The knowledge about the emerging and most discussed topics gives an overview of the global research trends of e-governance.

The study identified the evolution of creative collaborations in e-governance in the global perspective. The methodology introduced here is helpful to detect the proficient and productive author collaborations and the spectrum of related e-governance research topics associated with them. As the author collaborations can be mapped to the institutional and country-level collaborations, the information is helpful for researchers, institutions and governments to establish the best collaborations in e-governance research based on the author proficiency, collaboration patterns and research topics as per the requirements.

The paper introduces a novel research methodology using temporal analysis of co-author network to identify the evolution of research patterns and the associated research topics.

People with learning disabilities have high dependency needs and high prevalence of physical, psychological and social morbidities. Some studies have shown that South Asian and white populations have a similar prevalence of learning disabilities and related psychological morbidity (McGrother et al, 2002), although other studies have shown an increased prevalence of severe levels of learning disabilities in the South Asian population (Emerson et al, 1997). The aim of this study was to compare stress levels and unmet service needs in informal carers of South Asian and white adults with learning disabilities.A sample of 742 informal carers was selected from the Leicestershire Learning Disability Register. Data on carers' and subjects' demographic details, stress levels and unmet service needs were analysed and compared using chi‐square tests and logistic regression analyses. Substantial differences were observed between the two groups. Carers of South Asian adults with learning disabilities reported significantly higher levels of care provision and unmet needs. Major stress was reported in 23% of carers. This was more common in carers with poor health, in those caring for younger adults, carers of adults with psychological symptoms, and in those with an expressed need for moral support or respite care.Stress is common among informal carers of adults with learning disabilities and inequalities, in reported care given and unmet needs, exist between carers of South Asian and white adults. Practitioners need to be aware of factors associated with stress when assessing carers in this population.

The Royal College of Psychiatrists set up an interface group to look at the interface between old age psychiatry and learning disability and, as part of its work, the group commissioned a survey of learning disability and old age psychiatrists to investigate their experience of working across the boundary between the two specialities. This paper is based on the report produced. It summarises the findings of the survey and sets out eight recommendations to further the work. There was no clarity on how services should be provided to older people with a learning disability who develop a mental health problem in later life but the need for collaboration between the two specialities is compelling.

Clozapine is a well-known antipsychotic medication licensed for treatment-resistant schizophrenia, but there is limited research available to suggest its efficacy in the context of personality disorder and intellectual disabilities presenting with high-risk behaviour with or without psychotic symptoms. The purpose of this paper is to raise awareness of the benefits of using clozapine in patients with intellectual disabilities and personality disorder that present with a complex picture of serious risk of harm to both their life and the lives of others.

The authors present five patients with intellectual disabilities and serious life-threatening challenging behaviour whom were started on clozapine as part of their multidisciplinary treatment plan to manage their presentation. The authors completed baseline assessment of five main symptom domains and then repeated this assessment following treatment with clozapine.

In all five cases use of clozapine was objectively associated with an improvement in symptomatology, quality of life and a safe transfer to the community.

The findings suggest that judicious use of clozapine could be considered as one of the effective pharmacological strategies in the management of patients with intellectual disabilities and personality disorder who present with serious life-threatening challenging behaviours.

The purpose of current study deals with the development and wear testing of jute and cotton fiber reinforced with nano fly ash-based epoxy composites. Performance of waste cotton fabric nano hybrid composites are compared with waste jute fabric nano hybrid composites.

Basic hand layup technique was used to develop composites. To optimize the parameters and design of experiments, Taguchi design was implemented to test wear rate and co-efficient of friction as per ASTM standards. Performance of waste cotton fabric nano hybrid composites is compared with waste jute fabric nano hybrid composites.

Result shows that nano fly ash lowers the wear rate and co-efficient of friction in developed composites. Findings reveals that hybrid composites of waste jute Fabric with 3 Wt.% of nano fly ash performed best amongst all composites developed. Morphology of nano composites worn out surfaces are also analyzed through SEM.

Practically, textile waste, i.e. jute, cotton and nano fly ash (thermal power plant) all wastes, is used to develop composites for multi-function application.

Wastes are reused and recycled to develop epoxy-based composites for sustainable structures in aviation.

To the best of the authors’ knowledge, nano fly ash and jute, cotton combination is used for the first time to develop and test for wear application.

Lean management is a suitable methodology for companies that want to improve their productive performance and competitiveness. This study aims to research levels of implementation and internalisation of Lean production tools in Spanish manufacturing companies, and explores differences in behaviour between SMEs and large companies based on data gathered over three time periods. The correlation between Lean adoption and company performance is also analysed.

Company survey data for the years 2012, 2015 and 2018 collected from 354 respondents were used to conduct a longitudinal study on the level of lean tool adoption and internalisation in manufacturing companies.

Over the years, the use of Lean tools has increased, whereas levels of internalisation have remained stable. Lean tool use in SMEs and large companies show significant differences in 2012 and 2015, but this is no longer the case 2018. Results also show that higher Lean tool use helps increase return on sales (ROS), and higher levels of internalisation of tools helps reduce the number of products rejected.

To date, there are no known studies on the use and internalisation of Lean tools or their correlations with business performance indicators in Spanish manufacturing companies.

In recent years, the emergence of Industry 4.0 technologies as a way of increasing productivity has attracted the attention of the manufacturing industry. This study aims to investigate the relationship between Industry 4.0 technologies and lean tools (LTs) by measuring how the internalisation of LTs influences the adoption of Industry 4.0 technologies and how the synergy between them helps improve productivity in European manufacturing firms.

Results from 1,298 responses were used to analyse linear regression and study the correlation between the use of LTs and Industry 4.0 technologies.

Results show that the companies analysed tend to implement more Industry 4.0 technologies when their level of lean internalisation is high.

This study provides useful information for managers of manufacturing firms by showing the correlation between LT internalisation and Industry 4.0 technologies, corroborating that optimal implementation of these technologies is preceded by a high level of LT internalisation. Furthermore, although there are studies showing the relationship between LTs and Industry 4.0 technologies, none consider the intensity of their implementation.

The purpose of this paper is to study the mixed convection in a nanofluid along an inclined wavy surface embedded in a porous medium.

The complex wavy surface is transformed to a smooth surface by employing a coordinate transformation. Using the similarity transformation, the governing equations are transformed into a set of ordinary differential equations and then lineralized using the successive linearization method. The Chebyshev pseudo spectral method is then used to solve linearized differential equations.

The effects of Brownian motion parameter, thermophoresis parameter, amplitude of the wavy surface, angle of inclination of the wavy surface for aiding and opposing flows on the non-dimensional velocity, temperature, nanoparticle volume fraction, heat and nanoparticle mass transfer rates are studied and presented graphically.

This is the first instance in which mixed convection, inclined wavy surface and nanofluid is employed to model fluid flow.