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Design a MIMO printed dipole antenna for 5G sub-band applications
Get PDFYesIn this paper, a planar multiple input, multiple output (MIMO) dipole antenna for a future sub-6 GHz 5G application is proposed. The planar MIMO structure consists of 4 antenna elements with an overall size of 150×82×1 mm3. The single antenna element is characterized by a size of 32.5×33.7×1 mm3 printed on an FR-4 dielectric substrate with εr=4.4 and tanδ=0.02. The suggested antenna structure exhibits good impedance bandwidth equal to 3.24 GHz starting from 3.3 to 6.6 GHz with an S11 value of less than -10 dB (S11≤-10 dB) with antenna gain varying from 5.2 up to
7.05 dB in the entire band, which covers all the sub-6 GHz frequency band
of the 5G application. Good isolation is achieved between the MIMO elements due to low surface waves inside the MIMO antenna substrate. The radiation of the MIMO antenna structure can be manipulated and many beam-types can be achieved as desired. The high-frequency structure simulator (HFSS) software package is used to design and simulate the proposed structure, while the CST MWS is used to validate the results
A compact broadband Circularly Polarized wide-slot antenna with axial ratio bandwidth encompassing LTE 42 and LTE 43 standards of 5G mid-band
Get PDFYesThis study presents a compact broadband wide-slot antenna with broadband left-hand circular polarization compatible with both LTE 42 and LTE 43 standards of 5G mid-band applications. The proposed antenna is fabricated on an FR4 dielectric substrate with overall dimensions of , where is the free space wavelength at the resonant frequency of the antenna. The antenna ground plane is etched to form a square radiating slot with a pair of rectangular ground stubs that are diagonally placed inside the slot. On the other side of the antenna, the feed line is loaded by horizontal and vertical stubs to improve the coupling between the feed line and the square slot. To generate a circular polarization, the feeding stubs cooperate with the pair of rectangular ground stubs to excite the radiating slot of the antenna at two different feeding points whose currents have approximately equal amplitude and 90o phase shift. The measured impedance bandwidth (BW) of the proposed wide-slot antenna is 16.2% (580 MHz along the band 3.3-3.88 GHz), while the observed axial ratio bandwidth (ARBW) is 12.2% (440 MHz in the 3.4-3.84 GHz band). The measured gain values are found to be larger than 2.5 dB along both standards of the 5G mid-band applications.UK Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/E022936/1 and European Union's Horizon 2020 Research and Innovation Programme under Grant H2020-MSCA-ITN-2016 SECRET-722424
Intra and Inter-Rater Reliability of a Novel Isometric Test of Neck Strength.
Get PDFYesThere is no single, universally accepted method of measuring isometric neck strength to inform exercise prescription and injury risk prediction. This study aimed to establish the inter- and intra-rater reliability of a commercially available fixed frame dynamometer in measuring peak isometric neck strength. A convenience sample of male (n = 16) and female (n = 20) university students performed maximal isometric contractions for flexion (Flex), extension (Ext), left- (LSF) and right-side flexion (RSF) in a quadruped position over three sessions. The intra-rater reliability results were good-to-excellent for both males (ICC = 0.83–0.90) and females (ICC = 0.86–0.94) and acceptable (CV < 15%) across all directions for both males and females. The inter-rater reliability results were excellent (ICC = 0.96–0.97) and acceptable (CV < 11.1%) across all directions. Findings demonstrated a significant effect for sex (p ≤ 0.05): males were stronger in all four directions, and a significant effect for direction (p ≤ 0.05): Ext tested stronger (193 N) than Flex (176 N), LSF (130 N) and RSF (125 N). The findings show that the VALD fixed frame dynamometer can reliably assess isometric neck strength and can provides reference values for healthy males and females
Applications and life cycle assessment of shape memory polyethylene terephthalate in concrete for crack closure
No full textYesShape memory polymer (SMP) products have been developed for application as crack closure de-vices in concrete. They have been made from PET in the form of both fibres and hollow tubes. Here, manufacturing methods using die-drawing and mandrel-drawing to induce shape memory are reported. The fibre-based devices are incorporated into concrete and, upon triggering, exert shrinkage restraint forces that close cracks in the concrete. The evolution of shrinkage restraint force in the fibres as manufactured was measured as a function of temperature, showing stresses in excess of 35 MPa. Tendons consisting of fibre bundles are incorporated into concreate beams subjected to controlled cracking. When activated, the tendons reduce the crack widths by 80%. The same fibres are used to produce another class of device known as knotted fibres, which have knotted ends that act as anchor points when they incorporated directly into concrete. Upon acti-vation within the cracked concrete, these devices are shown to completely close cracks. The tubes are used to enclose and restrain prestressed Kevlar fibres. When the tubes are triggered, they shrink and release the prestress force in the Kevlar, which is transferred to the surrounding con-crete in the form of a compressive force, thereby closing cracks. The Kevlar fibres also provide substantial reinforcement after activation. The devices are shown to be able to partially and fully close cracks that have been opened to 0.3 mm and achieve post-activation flexural strengths com-parable to those of conventional reinforced and prestressed structural elements. Finally, a pre-liminary life cycle assessment study was used to assess the carbon footprint a nominal unit of concrete made with SMPs fibres compared to conventional concrete.This research was funded by the UKRI-EPSRC Resilient Materials 4 Life (RM4L), grant number EP/P02081X/1 and the support of ARUP via the UKIMEA research funding
The use of wearable activity trackers in schools to promote child and adolescent physical activity: A descriptive content analysis of school staff's perspectives
Get PDFYesThe school environment is an ideal setting for promoting physical activity (PA). Wearable activity trackers (wearables) have previously been implemented, in research, as intervention tools within the school-environment. However, the large-scale use and acceptance of wearables, in schools, is unknown.
This study distributed a cross-sectional survey to school staff to investigate the prevalence of child and adolescent wearable use in schools, including when and how they are used, and school staff's willingness to use them in the future (as implemented by school staff). This survey consisted of between 13 and 22 items, including closed-ended and open-ended questions. Closed-ended responses were displayed descriptively (wearable prevalence and characteristics), and open-ended qualitative responses were categorised using descriptive content analysis (how wearables are used).
1087 school staff provided valid responses. Of those, 896 (82.4%) had never used a wearable as a teaching or support tool for their students, and 120 (11%) currently used- and 71 (6.5%) had previously used- a wearable as a teaching or support tool for their students. When wearables were used, school staff implemented their use regularly and during physical education lessons or throughout the entire school day. Wearables were used to monitor or increase student's PA levels, or for student and staff educational purposes (e.g., academic learning, movement breaks). Most school staff were willing to use a wearable as a teaching or support tool to promote student's PA, and/or learning about PA, in the future.
This study is the first study to explore the widescale use and acceptance of children and adolescents using wearables in the school-setting. Findings may inform the development of future school-based interventions and public health initiatives for physical activity promotion, using wearables.This study is funded as part of a PhD studentship by the Born in Bradford study. The Born in Bradford study receives core infrastructure funding from the Wellcome Trust (WT101597MA) and the National Institute for Health Research (NIHR), under its NIHR ARC Yorkshire and Humber (NIHR200166) and Clinical Research Network (CRN) research delivery support. For this piece of work, funding from the Sport England’s Local Delivery Pilot awarded Born in Bradford funding for this PhD studentship. S.A.C is supported by the NIHR Leicester Biomedical Research Centre—Lifestyle theme
Acid Gas Removal by Superhigh Silica ZSM-5: Adsorption Isotherms of Hydrogen Sulfide, Carbon Dioxide, Methane, and Nitrogen
Get PDFYesThe adsorption of acid gas, including hydrogen sulfide and carbon dioxide, by superhigh silica ZSM-5 was investigated. Equilibrium adsorption isotherms of high-purity hydrogen sulfide and carbon dioxide were measured experimentally using this new sorbent. In addition, methane and nitrogen adsorption isotherms on this MFI-type zeolite were also measured as representative of other natural gas components. To enhance the reliability of the results, the adsorption pressure has been selected up to 20 bar at three different temperatures. Superhigh silica ZSM-5 for the adsorption of hydrogen sulfide shows an impressive result of 3.04 mmol·g–1 at 12 bar and 283 K. This value was 2.69 mmol·g–1 for carbon dioxide at 21 bar and 283 K. The adsorption capacity of H2S on the ZSM-5 is the highest, and N2 is the lowest; the order of the adsorption capacities of components is H2S > CO2 > CH4 > N2. The adsorption heat of different adsorbates is calculated: 13.7 and 29.5 kJ·mol–1 for H2S and CO2, respectively. Physical adsorption has occurred on high-silica ZSM-5, especially for hydrogen sulfide, and this is a great advantage. By increasing the temperature, the adsorption capacity of components on the ZSM-5 decreases, but due to differences in the adsorption heat of the adsorbate, the ideal selectivity for hydrogen sulfide increases. There is a challenge in the choice of the best condition for H2S removal, as, by increasing the temperature, the adsorption capacity of hydrogen sulfide reduces, but the selectivity of the hydrogen sulfide increases as compared to other gases. This phenomenon is not true for the selectivity of other components
Numerical study on flexural and bond-slip behaviours of GFRP profiled-concrete composite beams with groove shear connector
Get PDFYesGFRP profiled-concrete composite beams with groove shear connectors are analyzed using finite the element (FE) analysis. The concrete damaged plasticity (CDP) model was adopted for normal strength concrete (NSC) and reactive powder concrete (RPC). The orthotropic behaviour of GFRP profile was taken into consideration, and the bi-linear traction-separation model was used to investigate the bond-slip behavior between GFRP profile and concrete. Furthermore, parametric studies were conducted to investigate the effects of strength and the cross-sectional dimensions of concrete, strength (orthotropy), and the cross-sectional dimensions (the web height and the thickness of FRP plate). Numerical analysis results correlate well with experimental results. Based on numerical analysis, the composite beam with shear connectors spacing at 100 mm has a deflection-limit load of 21.4 % higher than the specimens with 150 mm spacing. It is possible to improve the bonding behavior of interfaces by using groove shear connectors. The ultimate load and deformation, and pseudo-ductility were significantly improved by using RPC with high strength and toughness (ultimate compressive strain). GFRP profiles with greater orthotropy coefficients provide fully utilized concrete's compressive strength, preventing premature crushing and enhancing composite structure stiffness. Flexural performance of the composite beams can be improved efficiently by choosing the appropriate sectional size during design and construction.Natural Science Foundation of Jiangsu Province, China (BK20201436), the Science and Technology Project of Jiangsu Construction System (2018ZD047, 2021ZD06), the Science and Technology Project of Gansu Construction System (JK2021-19), the Open Foundation of Jiangsu Province Engineering Research Center of Prefabricated Building and Intelligent Construction (2021), the High-End Foreign Experts Project of Ministry of Science and Technology, China (G2022014054L), the Science and Technology Cooperation Fund Project of Yangzhou City and Yangzhou University (YZU2022194, YZU212105), the Blue Project Youth Academic Leader of Colleges and Universities in Jiangsu Province (2020), the Science and Technology Project of Yangzhou Construction System (2022ZD03, 202204) and the Technology Innovation Cultivation Fund of Yangzhou University (2020-65)
A systematic review study on the factors affecting shortage of nursing workforce in the hospitals
No full textYesThis study aimed to determine factors that influence the nursing workforce shortage and their impact on nurses.
This study applied a systematic review design.
Using Cochrane library guidelines, five electronic databases were systematically searched (Research 4life-PubMed/Medline, Scopus, Embase, CINAHL) from 2010-2021. The remaining articles with pertinent information were presented in a data extraction sheet for further thematic analysis. A Reporting Items for Systematic Reviews and Meta-Analysis Flow Diagram was adopted and used. The studies published from 2010-2021 and in English language were examined and included in the systematic review.
Four themes were identified as factors influencing the nursing workforce shortage, including Policy and planning barriers, Barriers to training and enrolment, Factors causing nursing staff turnover and Nurses' stress and burnout. Nursing workforce shortage is a global challenge that roots in multiple causes such as individual, educational, organizational and managerial and policy-making factors
Identity, immigration and subjective well-being: Why are natives so sharply divided on immigration issues?
Get PDFYesWe put forward differences in the form of national identity across natives as a key mechanism explaining the sharp public divide on immigration issues. We show that inflows of migrants into local areas can be harmful for the self-reported well-being of natives, but this is only true for natives who self-identify with an ethnic form of national identity. On the other hand, we provide some evidence to suggest that immigration may be utility enhancing for natives with a civic form of national identity. We also show how differences in national identity significantly predicts voting preferences in the UK referendum on EU membership where concern with immigration issues was a salient factor. Drawing on identity economics, our proposed explanation is that for natives with an ethnic form of national identity, any positive economic benefits associated with immigration may not be enough to outweigh losses in identity based utility.This work was supported by the Nuffield Foundation
