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COVID-19 has influenced the way we utilise the radio spectrum in terms of increasing data rates, the localisation of usage, and the transfer of traffic from urban to rural areas. Most regulators have shown sympathy towards operator requirements, stipulating a range of mitigation actions including allowing technology neutrality and temporary assignments. Internationally, the ITU-R suspended all physical meetings and launched a new global network resiliency platform named ‘REG4COVID’ to share experiences including those related to spectrum management.

It is argued in this chapter that the pandemic has supported the calls for additional unlicensed spectrum for Wi-Fi in the 6 GHz and accelerated the rollout of 5G. Moreover, despite of increasing use of streaming, it is quite difficult to assume that traditional linear TV will be replaced, at least in the near future for a variety of reasons. The pandemic has also raised the question as to whether an innovative assignment model could be used to assign the spectrum instead of auctions, and whether, in some countries where temporary assignments were made, frequencies are kept unutilised or reserved. Concerning international spectrum management, it is expected that WRC-23 will be held on time though there will be some implications for issues such as the regulatory time-limits for bringing into use satellite networks frequency assignments. Finally, it is argued that the pandemic has also demonstrated the importance of flexibility and agility in national spectrum management, and placed spectrum managers in a new position where they were forced to be proactive instead of their traditional reactive role.

The present paper answers two significant questions: (1) What are the relative consumer and firm-level effects of marketing through metaverse compared to conventional marketing endeavors? (2) What are the current trends in utilizing the metaverse as reported in the recent literature?

This study employs a systematic literature review methodology, utilizing a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart to synthesize existing research. Thirty-five articles written in English were selected and analyzed from two databases, Web of Science and EBSCO Host.

The findings indicate that consumer-level effects of the metaverse include consumer loyalty and brand attachment. The firm-level benefits are decentralization and cost reductions. The paper proposes a framework indicating variables that could attenuate or enhance the association between immersive components of the metaverse and their resultant effects.

This study contributes to understanding the role of metaverse in marketing practices related to the marketing mix components. The study conceptualizes a novel framework for the metaverse and its resultant effects.

This chapter presented cognitive radio networks in construction. The construction industry requires an efficient bandwidth of wireless technology for effectiveness without delay. The persistence of challenges with the investment in third generation is a great concern, and this chapter identified investing in fifth generation (as an alternative) to enlarge bandwidth for better effectiveness that is capable of dealing with unavailable or scarcity of radio spectrum. The application of fifth generation will permit efficient utilisation of the radio spectrum by the primary and secondary users to detect the spectrum parameters which will highlight the direct and adequate interaction with the radio channel. This chapter further considered the usage of this technology as it relates to permitting sharing of sense in the spectrum.

The purpose of this research is to investigate the acceptance and support of neurodiverse people in society, with a focus on autism, and to use this to propose a framework to enhance inclusivity that can inform pedagogy within the education sectors.

Three case studies from higher education have been presented and mapped onto a multi-dimensional spectrum of characteristics normally associated with autistic people. Further examples have been taken from the general population and these have been used, along with user scenarios to propose a framework for inclusivity.

A framework, the human spectrum, has been proposed which encompasses all of society, regardless of diagnoses and within which people have mobility in terms of their characteristics. It is proposed that this framework should be incorporated into pedagogy in primary, secondary and tertiary education so that teaching and assessment is inclusive and so that people’s understanding of human nature is built from an early age to counter stigma and herd mentality, or othering.

The contribution of this paper could have significant implications for society as the framework provides a structure to enable people to consider others with new perspectives.

The framework proposed provides a new and original way of shaping the way people think within the education sector and elsewhere.

The purpose of variable loading conditions (392 N-785N-392N-785N) with break-in period were used to study interactions between zinc dialkyl dithiophosphate (ZDDP) 0.1 P% (phosphorus) and fine-grade molybdenum disulfide (MoS₂) 3%, in different mixtures of NLGI 2 lithium stearate grease. Four-ball wear tests were used to evaluate the tribological properties of different grease mixtures such as coefficient of friction and wear. ASTM 2266 as reported by earlier studies is useful, but it is not representative of real-life applications where variable loads and speeds and different break-in periods play a role and could change the results and the nature of tribofilms.

In this study, chemical and mechanical properties of tribofilms were examined. Moreover, design of experiment was used to examine the data and shorten experimentation time. Research described here is investigating variable loading conditions for real-life applications by using a break-in period of 2 min at the start to minimize asperities and establish a clean surface. Design expert (DOE) analyzes responses to reveal those variables that are single factor and those that are multifactor whether synergistically or antagonistically.

The results indicated that spectrum loading with break-in period showed reduction in wear when tested in greases with ZDDP/MoS₂ combinations. Ramping up or down the load every 7.5 min for a rotational speed of 1,200 rpm and a total of 36,000 revolutions or 30-min time slowed the wear properties of lithium-based grease under different MoS₂ and ZDDP concentrations. Experiments indicated that wear was largely dependent on the loading condition and ZDDP additives during specific break-in period at 1,200 rotational speed. It is believed that MoS₂ greases perform better under spectrum loading and under constant loading when mixed with ZDDP phosphorus.

This research indicates that there is a synergistic interaction between ZDDP, MoS₂ and variable loading especially when a break-in period is applied. The results indicated that wear was largely dependent on the specific speed used with spectrum loading as presented in the energy dispersive spectroscopy and the Auger electron spectroscopy analysis, and thus a 3% MoS₂ grease with ZDDP (phosphorus: 0.1 Wt.%) are needed to improve the wear resistance and improve the friction characteristics.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0016/

This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

Since the performance of vehicular users and cellular users (CUE) in Vehicular networks is highly affected by the allocated resources to them. The purpose of this paper is to investigate the resource allocation for vehicular communications when multiple V2V links and a V2I link share spectrum with CUE in uplink communication under different Quality of Service (QoS).

An optimization model to maximize the V2I capacity is established based on slowly varying large-scale fading channel information. Multiple V2V links are clustered based on sparrow search algorithm (SSA) to reduce interference. Then, a weighted tripartite graph is constructed by jointly optimizing the power of CUE, V2I and V2V clusters. Finally, spectrum resources are allocated based on a weighted 3D matching algorithm.

The performance of the proposed algorithm is tested. Simulation results show that the proposed algorithm can maximize the channel capacity of V2I while ensuring the reliability of V2V and the quality of service of CUE.

There is a lack of research on resource allocation algorithms of CUE, V2I and multiple V2V in different QoS. To solve the problem, one new resource allocation algorithm is proposed in this paper. Firstly, multiple V2V links are clustered using SSA to reduce interference. Secondly, the power allocation of CUE, V2I and V2V is jointly optimized. Finally, the weighted 3D matching algorithm is used to allocate spectrum resources.

The concept of “participation” has become a buzzword in contemporary public governance models. However, despite the broad and significant interest, defining participation remains a debated topic. The aim of the current study was to explore how participants perceived and interpreted the meaning and scope of participation.

This study is part of a four-year (2019–2022) longitudinal research project investigating stakeholder participation in the context of developing and establishing a strategic regional plan in Region Skåne in southern Sweden. The research project has a qualitative approach and uses interviews with different stakeholder groups such as municipal politicians and public officials and a survey as empirical material.

The authors developed a participation spectrum including eight types of participation: to be open, to be informed, to be listened to, to discuss, to be consulted, to give and take, to collaborate and to co-create. The authors also identified four different purposes of participation: creating a joint network, creating a joint understanding, creating a joint effort and creating a joint vision. The spectrum and the purposes were related through four characteristics of participation, i.e. involvement, interaction, influence and empowerment.

The study rests on a single case, and so the results have limited transferatibility.

Researching participation in terms of the participants' perceptions contributes a new perspective to the existing literature, which has commonly focussed on the organizers' perceptions of participation. Moreover, in order to clarify what participation meant to the participants, the study puts emphasis on untangling this from the why question of participation.

This scoping review aims to (1) summarize research and design writings on residential design for adults on the autism spectrum in peer-reviewed and grey literature, (2) identify research gaps in this field and (3) understand the concept of independent living based on this literature.

A systematic search was conducted in seven databases using 47 search terms related to residence, design and autism. It was supplemented with a manual search for recommended authors and architectural websites.

A final review of 37 sources highlighted that existing residential design guidelines are supported by weak evidence due to the lack of methods for involving and limited direct contact with autistic adults. Moreover, the needs of people living or working with them tend to be overlooked. Finally, the role of independent living has received little attention in the literature on residential design for adults on the spectrum.

The findings show a need for taking on board autistic people's understanding of independent living. Future research about residential design for autistic adults should be conducted with them, in diverse housing settings, providing nuanced insight into their housing needs and those of the people around them.

This scoping review is the first to provide an overview of what is known about residential design for autistic adults with a focus on the concept of independent living.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.