Practical Design Considerations Research Articles

Numerical investigation of punch-through mitigation in stiff-over-soft clays using skirted spudcan

Punch-through failure, a critical issue in offshore engineering, occurs when a foundation penetrates through strong-over-weak soil layers. This paper presents a study on the effectiveness of skirt addition to spudcans in addressing punch-through failure through numerical simulations using the axisymmetric Particle Finite Element Method (PFEM). The validity of the PFEM is verified by simulating a spudcan penetration centrifuge test. Subsequently, PFEM simulations are conducted to analyse the penetration behaviour of both generic and skirted spudcans in stiff-over-soft clays. Results from the simulations reveal the bearing responses of spudcans as they penetrate into clays, elucidate associated failure mechanisms, and underscore the significant of considering the spudcan-driving process in estimating punch-through failure mitigation. Findings indicate that, the skirt effectively mitigates punch-through failure by increasing plug height in the lower soft layer, thus reducing the rate of bearing capacity reduction. Furthermore, critical factors such as skirt length, upper layer thickness, lower layer strength gradient, and the strength ratio between lower and upper layers are assessed through comprehensive parametric studies to evaluate the efficacy of skirted spudcans in mitigating punch-through failure, with eventual goal to provide essential guidance for practical design considerations in offshore foundation systems.

Comparative Study of Optimal Flat Double-Layer Space Structures with Diverse Geometries through Genetic Algorithm

This paper investigates the structural performance of flat double-layer grids with various constitutive units, addressing a notable gap in the literature on diverse geometries. Six common types of flat double-layer grids are selected to provide a comprehensive comparison to understand their structural performance. Parametric models are built using Rhino and Grasshopper plugins. Single- and multi-objective optimization processes are conducted on the considered models to evaluate structural mass and maximum deflection. The number of constitutive units, the structural depth, and the cross-section diameter of the members are selected as design variables. The analysis reveals that the semi-octahedron upon square-grid configuration excels in minimizing structural mass and deflection. Furthermore, models lacking a full pyramid form exhibit higher deflections. Sensitivity analyses disclose the critical influence of the design variables, particularly highlighting the sensitivity of structural mass to the number of constitutive units and cross-section diameter. These findings offer valuable insights and practical design considerations for optimizing double-layer grid space structures.

Utilising AI-powered Chatbots for Learning Endangered Nigerian Languages and Considerations for Their Development

Younger generations in Nigeria increasingly use English over their native languages, leading to a decline in indigenous language use in public and professional settings and risking language loss. Consequently, this study explores the potential of AI-powered chatbots in aiding the learning of endangered Nigerian languages. The objectives are to determine how chatbots can support language learning, identify the essential functionalities required for effective learning, and outline design considerations to address the specific challenges faced by these languages. The research employs a qualitative approach, using secondary data from existing literature on language revitalisation, AI chatbots, and Nigerian languages. The analysis reveals that AI chatbots can significantly enhance language learning through features such as handling tonal distinctions and syntactic operations present or allowed in the languages, providing feedback, and engaging learners. Practical design considerations for developers include integrating these functionalities to create effective language-learning tools. These findings suggest that integrating AI technology into language preservation efforts can offer an innovative solution to revitalise endangered Nigerian languages and ensure their continued use among future generations.

Gamified immersive safety training in virtual reality: a mixed methods approach

PurposeThe reemergence of immersive virtual technology (IVR) provides both opportunities and challenges for workplace learning (WPL). The purpose of this study is to explore and develop knowledge about how gamification influences the WPL experience by addressing two research questions: RQ1. What characterizes a gamified immersive safety training experience with IVR technology? and RQ2. How does gamified immersive safety training with IVR technology impact the WPL experience?Design/methodology/approachThe study adopted a mixed methods approach by combining a systematic literature review with a case study on an empirical project about immersive fire safety training for train operators that are used at the Swedish train operating company SJ. The case study included data from semistructured interviews, Web survey and observation studies. The data was analyzed in two stages combining inductive and deductive data analysis for identifying themes and categories.FindingsThe findings of the study are twofold: (1) themes that conceptualize the gamified immersive safety training experience based on outputs from both the literature review and the first round of data analysis; and (2) a framework with three overarching categories that are mapped with the identified themes, and which were deduced throughout the second round of data analysis.Originality/valueThe originality of the findings stresses the implications of how a body of knowledge that synthesizes gamification concepts with immersive safety training, can inform the design of WPL experiences that are facilitated with IVR technology. As such, the implications of the findings are targeted toward both the advancement of the IVR discourse in the WPL field, but also toward practical considerations for design of immersive learning experiences that enrich WPL practices and culture.

Advanced analysis and construction techniques for long-span spatial structures in steel engineering

This paper explores advanced analysis methods and construction techniques for long-span spatial structures in steel engineering. It delves into the principles of the Direct Analysis Method (DAM), emphasizing equilibrium, compatibility, plasticity, and stability, as well as load path and redundancy considerations. The DAM provides a robust framework for analyzing complex steel structures, ensuring stability, resilience, and efficiency. Furthermore, the paper discusses modeling techniques, including Finite Element Analysis (FEA), dynamic analysis, and nonlinear analysis, highlighting their significance in optimizing design solutions and predicting structural behavior under diverse loading conditions. Practical considerations in material selection, connection design, and construction are addressed, focusing on enhancing performance, durability, and constructability. Prefabrication and modular construction techniques are explored as effective strategies for accelerating project schedules, improving quality control, and enhancing site safety. Through a comprehensive review of literature and case studies, this paper provides valuable insights for engineers and researchers involved in the design and construction of long-span spatial structures in steel engineering.

A qualitative study exploring the opportunities and challenges of providing digital community pharmacy services for older people in England

Abstract Introduction Digital healthcare can be an innovative, cost-effective solution for the growing healthcare needs of an ageing population, enhancing service accessibility.[1] Older individuals tend to rely more on community pharmacy services, supported by research indicating positive health outcomes.[2] However, scant evidence exists regarding the impact of digital community pharmacy services on this demographic, emphasising the need for crucial investigations into their effectiveness. Aim Identify challenges and opportunities in delivering digital pharmacy services for older population in community pharmacies in England, from perspectives of policymakers and pharmacy service providers. Methods Between November 2022 and May 2023, online/telephone interviews were conducted with stakeholders including policymakers/commissioners and pharmacy service providers. Recruitment involved purposive and convenience sampling, with commissioners sourced through networks and pharmacy providers via gatekeepers in industry associations. Topics covered the current state of digital pharmacy services in England, implementation opportunities and challenges, and suggestions for enhancement. Audio-recorded interviews were transcribed verbatim and analysed using both inductive and deductive thematic approaches, assisted by NVivo 12 Plus. Themes comprised challenges and solutions in digital pharmacy service delivery and factors influencing user acceptance. Deductive analysis shaped the coding framework based on Davis’s Technology Acceptance Model (TAM). Results Twelve interviews (three policy makers/commissioners [PM], four senior managers of community pharmacy [SM], five front-line community pharmacists [CP]) were completed. One of the interviewees was a female and all others were male. Their length of relevant employment in the field of community pharmacy ranged from three to seventeen years. The key findings indicated challenges in implementing digital pharmacy services to older populations may be due to unclear health policies and limited financial support for digital reforms to community pharmacy: “as a pharmacy we’ll take care of that, but we need to know that there will be funding for that before we go and do it all. I think there’s amazing things that can be done, but at local, small level, like a little community pharmacy, they just can’t afford to do the development” [SM1], and “so the majority of independent pharmacies, … they have paper prescriptions, so they’re not as technology based. I believe one, that’s because it’s money, so it’s funding. They get less funding” [CP4]. Interviewees highlighted that community pharmacists facing high workloads and time constraints, often prioritise other responsibilities over adopting new technologies: “unfortunately, there are a fair few demands on pharmacy team’s time at the moment, so where does promoting a digital priority fit on that long list of priorities and probably quite low down” [PM3]. They also expressed a need for additional technical training to effectively navigate digital pharmacy services. Conclusion This study provides insights into challenges in implementing digital pharmacy services for older people through diverse stakeholder perspectives, offering practical considerations for policy decisions, service design, and implementation strategies. Nevertheless, this study observes a deficient emphasis on deploying digital pharmacy services for older people. It is orientated towards a broader demographic, while those with specific medical conditions may receive pharmacy services more precisely. The applicability of this study may be limited, requiring region-specific research. Further research would be focusing on those over 50 in Greater Manchester aligns with the local community’s emphasis on ageing-related research, technology, and innovative ideas supported by academic institutions.

Effect of mix dosage on rubberized concrete mechanical performance: A multivariable prediction model towards design provisions

The accumulation of end-of-life tires generates significant environmental/economic/social problems worldwide; however, these tires can potentially be used in engineering applications when recycled as crumb rubber (CR). One possibility is to use CR as a replacement for river sand in concrete to reduce the disposal of CR and the use of sand as well as to improve some of concrete’s properties, such as thermal performance and carbon footprint at the expense of some compressive strength reduction. In this study, a novel and simple multivariable model was developed to predict the compressive strength reduction of rubberized concrete (RC) based on a dataset of 287 concrete mixtures from 38 different studies. The approach used in this study quantified the significance of the impact of 10 mix design variables on the evaluation of compressive strength reduction. The final model proposed in this paper considers six explanatory variables (i.e., volume replacement of sand by CR, CR quantity, fine aggregate quantity, coarse aggregate quantity, cement quantity, and water quantity) to predict the compressive strength reduction in which a logarithmic transformation was implemented to achieve a more precise model. The proposed model reached a coefficient of determination of 0.89, significantly better than other existing models with which the proposed model was compared, resulting in a highly accurate and yet easy-to-implement model. Finally, practical design considerations were provided to be used in concrete mix design or the design of minor structural elements.

Confinement-based direct design of axially-compressed octagonal concrete-filled double skin steel tubes

Prior research has highlighted distinctions in the confinement mechanism for concrete-filled double-skin steel tube (CFDSST) columns with octagonal sections compared to circular and square sections. Current design codes primarily address the models for the design of square and circular sections in columns made of concrete-filled steel tube (CFST). This study addresses this gap by presenting a novel confinement-based direct design model specifically developed for octagonal CFDSST columns, encompassing both unstiffened and stiffened outer steel tubes. Initial data collection involved experimental and numerical results of axially-compressed octagonal CFST and CFDSST columns sourced from literature. Subsequently, ultimate compressive resistance, as determined by international design codes (EC4, ACI-318, AISC-360, GB-50936, T/CCES-7, AS/NZS-2327, CSA-S16, AIJ) and existing analytical models, underwent comparison with test results. The results reveal that existing codes and models generally offered accurate predictions, but their consistency across the entire side width-to-thickness (w/to) ratio range varied. The study proposes a new confinement design model for predicting the compressive resistance of octagonal CFDSST columns. Although the new model does not outperform existing ones, it demonstrates satisfactory prediction scatter throughout the w/to ratio and compressive strength (fc′) range, particularly excelling in high-strength concrete (HSC) and ultra-high-strength concrete (UHSC) scenarios. Notably, the proposed formula incorporates the influence of stiffening ribs on the confinement of the octagonal steel tube on concrete, making it applicable for practical design considerations for both unstiffened and stiffened octagonal CFDSST columns.

Fluid‐structure interaction study of an oscillating heat source effect on the natural convection flow

AbstractThe objective of this paper is to investigate fluid‐structure interaction (FSI) within conjugate natural convection. An oscillating fin, featuring a heat source placed at different locations, is examined using the Arbitrary Lagrangian–Eulerian formulation. The Galerkin finite element method is utilized to solve nonlinear dimensionless equations. Verification of grid independence is conducted and the model undergoes validation. Simulation outcomes for three fin positions (left, center, and right) and three heat source locations (bottom, middle, and top) are presented, illustrating streamlines, isotherms, and the average Nusselt number. The governing equations and boundary conditions are addressed using the finite element method. Temperature profiles in four scenarios are analyzed, along with horizontal velocities at different levels (0, D/2, D from the bottom wall). Dimensionless time (10−5 ≤ t ≤ 3), Ra = 106, Kr = 10, E = 1011 are used as parameters. The impact of the heat source position on vibratory motion is evaluated through Nusselt number variation, affecting heat exchange in different cases. The results show that heat transfer is minimal for a source location at the center of the fin (c). These findings also offer insights into FSI applications in economics and industry, guiding practical design considerations. Additionally, coupling the vibratory motion of the heat source with the flexible oscillating fin at the same frequency enhances understanding of the system.

Si Nanowires: From Model System to Practical Li-Ion Anode Material and Beyond.

Nanowire (NW)-based anodes for Li-ion batteries (LIBs) have been under investigation for more than a decade, with their unique one-dimensional (1D) morphologies and ability to transform into interconnected active material networks offering potential for enhanced cycling stability with high capacity. This is particularly true for silicon (Si)-based anodes, where issues related to large volumetric expansion can be partially mitigated and the cycle life can be enhanced. In this Perspective, we highlight the trajectory of Si NWs from a model system to practical Li-ion battery anode material and future prospects for extension to beyond Li-ion batteries. The study examines key research areas related to Si NW-based anodes, including state-of-the-art (SoA) characterization approaches followed by practical anode design considerations, including NW composite anode formation and upscaling/full-cell considerations. An outlook on the practical prospects of NW-based anodes and some future directions for study are detailed.

Surface acoustic wave spectroscopy for non‐destructive coating and bulk characterization at temperatures up to 600°C enabled by piezoelectric aluminum nitride coated sensor

Surface acoustic wave spectroscopy has been established as non‐destructive and fast method for characterization of mechanical properties of surfaces and bulk materials in both research and industry. The present work shows that by application of a novel and robust aluminum nitride (AlN) coated piezoelectric contact sensor the advantages of the method can be extended from room temperature to at least 600°C. An overview of sensor concepts and applications of the method is discussed first, followed by theoretical and practical considerations for design and coating of a novel temperature stable contact sensor. After fabrication of such a sensor using magnetron sputtering, it was tested in a modified surface acoustic wave spectroscopy setup with an incorporated heating table concerning signal amplitude and frequency range. The AlN coated sensor was found to perform well up to 600°C, with temperature limited by the specification of the heating table. At room temperature, performance was acceptable when compared with a conventional contact sensor using a PVDF piezoelectric foil. Application of the high temperature capabilities of the setup was demonstrated by measuring temperature stability of hydrogen‐free amorphous carbon coatings (a‐C and ta‐C) depending on their sp3 carbon ratio. In another example, high precision temperature dependent measurement of Young's modulus for ultrasonic fatigue test specimen was taken, achieving an accuracy better than 1%. Use of the developed sensor opens up new possibilities in material science for in situ study of temperature depending mechanical properties for coatings and surfaces.

Semiotic scale for library software interfaces: Development and validation

AbstractThis study presents a significant advancement in the realm of information science by exploring and validating a semiotic scale tailored for library software interfaces. Employing a design‐based approach, the investigation identifies 14 crucial semiotic elements specific to library software interfaces, forming the cornerstone of its theoretical framework. The process of developing the semiotic scale involves creating user personas, conducting a comprehensive semiotic analysis, and engaging in productive collaboration with experts. Through meticulous evaluation and refinement, achieved by expert assessments and user testing, the scale offers actionable insights for guiding interface enhancement. The study's findings encompass a breadth of revelations, including user needs, user personas, outcomes of semiotic analysis, criteria development, and evaluation results across a diverse range of library software interfaces. Serving as a valuable tool for interface designers, the semiotic scale facilitates the alignment of design choices with user preferences and requirements. Its inherent adaptability ensures applicability across a spectrum of library software interfaces. The study's paramount contribution lies in bridging the gap between theoretical semiotics and practical design considerations. The comprehensive model offered by the development and validation of the semiotic scale empowers the evaluation of semiotic elements' impact on user perceptions and interface usability.

A protocol to simultaneously examine cardiorespiratory, cerebrovascular and neurophysiological responses inside a hypobaric chamber.

We describe a protocol to examine neurophysiological (electroencephalography, EEG), cerebrovascular (ultrasound assessments of middle cerebral artery blood velocity, MCAv) and cardiorespiratory (blood pressure, oxygen saturation, end-tidal gases, respiratory rate) responses inside a hypobaric chamber. This procedure aims to standardize the methodology in experiments conducted within a hypobaric chamber such as comparing normobaric and hypobaric hypoxia. This is important because current understanding of relationships between neurophysiological activity, and cerebrovascular and cardiorespiratory responses under varying environmental conditions remains limited. This procedure combines simultaneous neurophysiological, cardiorespiratory and cerebrovascular evaluations, allowing a comprehensive understanding of electro-neurophysiological activity. Our protocol requires an hour and a half of equipment setup, 1-1.5 hours of participant set-up, and 30 minutes of experimental data collection. Since multiple simultaneous physiological recordings, including EEG in this environment, can be fraught with pitfalls, we also provide practical considerations for experimental design and recording setup. Advanced knowledge of hypobaric chamber operation is required, alongside expertise in EEG and transcranial Doppler ultrasonography. Following our procedure one will acquire simultaneous recordings of neurophysiological, cerebrovascular and cardiorespiratory data.

Effect of Reaching Movement Modulation on Experience of Control in Virtual Reality

Users’ motion representation in virtual reality (VR) can be modulated visually by introducing a mismatch with their real motion, which can bring benefits to exercise and rehabilitation and has great potential for exergame applications in VR. Users’ experience of control is a critical consideration for user experience in human–computer interaction and should be paid special attention when movement modulation is implemented in VR. However, how movement modulation affects users’ experience of control and motor performance has not been fully investigated in detail. This research included 49 participants and investigated how the experience of control is influenced by reaching movement modulation in two types: the enhancement and reduction modes. Different modulation modes were designed to study their influence on the explicit experience of control in self-ratings and the implicit measured experience of control in intentional binding and electroencephalography. Participants’ movement trajectory, velocity, and completion time were analyzed for motor performance. The results illustrate a significant effect of movement modulation on the users’ motor performance and experience of control in self-ratings and EEG. This study makes a major contribution through a comprehensive analysis of the experience of control with movement modulation and provides important and practical design considerations on movement modulation design in future exercise-based applications with positive controlling experiences in VR.

A Review on Malicious URLs Detection Using Machine Learning Methods

Malicious URLs are a serious threat to cybersecurity because they can compromise user security and inflict large financial losses. The extensiveness and adaptability of traditional detection approaches which rely on blacklists are limited when it comes to rapidly emerging threats. In response, machine learning methods have become more popular as a means of improving the detection efficiency of malicious URLs. This paper provides a thorough analysis providing a structured understanding of all aspects and formal formulation of the machine learning job of malicious URL detection. It covers feature representation and algorithm design, classifying and reviewing contributions from literature studies. The survey aims to provide a state-of-the-art understanding and support future research and practical implementations. It targets a diverse audience, including experts, cybersecurity professionals and machine learning researchers. The article provides a comprehensive overview of the field discussing practical system design considerations, ongoing research challenges and future research directions.

Basket Trials: Past, Present, and Future

Large-scale tumor molecular profiling has revealed that diverse cancer histologies are driven by common pathways with unifying biomarkers that can be exploited therapeutically. Disease-agnostic basket trials have been increasingly utilized to test biomarker-driven therapies across cancer types. These trials have led to drug approvals and improved the lives of patients while simultaneously advancing our understanding of cancer biology. This review focuses on the practicalities of implementing basket trials, with an emphasis on molecularly targeted trials. We examine the biologic subtleties of genomic biomarker and patient selection, discuss previous successes in drug development facilitated by basket trials, describe certain novel targets and drugs, and emphasize practical considerations for participant recruitment and study design. This review also highlights strategies for aiding patient access to basket trials. As basket trials become more common, steps to ensure equitable implementation of these studies will be critical for molecularly targeted drug development.

Understanding participant perspectives around HIV cure-related studies involving antiretroviral analytical treatment interruption in the United Kingdom

BackgroundTo test efficacy, HIV cure-related trials often require a period of intensively monitored interruption of antiretroviral therapy (ART) (analytical treatment interruption or ATI). As individuals who started ART during primary HIV infection (PHI) are often recruited, we asked people already enrolled in an observational PHI study about their willingness and concerns around participating in cure-related studies involving ATIs. MethodsPeople who were diagnosed with PHI and started ART, attending two London HIV clinics, provided informed consent to complete a digital survey in clinic between 21/07/21 to October 31, 2023. Questions comprised of sociodemographics, motivations, concerns and practical considerations influencing willingness to participate in studies involving ATI. Hierarchical clustering of responses was performed using the ‘pheatmap’ R statistical package and ranked from most to least concerned. Responses were cross-referenced with enrolment into an ATI study which recruited from this cohort. ResultsOf 352 eligible participants, 75 completed the survey. The majority were white, cisgender men who have sex with men, 34/75 (45 %) were born outside the UK. 29 (39 %) expressed interest in joining ATI studies. Participants who were interested or unsure in joining ATI studies were primarily motivated (53/65, 82 % very or moderately interested) by an altruistic desire to help scientific research. Across all participants, onward HIV transmission was the predominant concern (67/75, 89 % very or moderately concerned), and similar levels of concerns reported if the HIV viral load threshold to restarting ART was increased from 500 to 50 000 copies/mL. Most participants preferred weekly (23/65, 35 %) or fortnightly (11/65, 17 %) viral load monitoring during an ATI. Before taking part in a study involving an ATI, participants stated they would prefer to discuss this with their HIV doctor (55/65, 85 %). ConclusionIn this small survey, 39 % of respondents expressed interest in joining studies involving ATIs, primarily for altruistic reasons. Participants were more interested in joining a potential ATI study if a novel intervention was included than simply an ATI alone. The main concern expressed was risk of viral transmission. To inform practical and study design considerations for future ATI studies, unrestricted access for mitigation of transmission risk should be included, and regular, frequent viral load monitoring is preferred.

Practical Design Considerations for Wide Locally Recoverable Codes (LRCs)

Most of the data in large-scale storage clusters is erasure coded. At exascale, optimizing erasure codes for low storage overhead, efficient reconstruction, and easy deployment is of critical importance. Locally recoverable codes (LRCs) have deservedly gained central importance in this field, because they can balance many of these requirements. In our work, we study wide LRCs; LRCs with large number of blocks per stripe and low storage overhead. These codes are a natural next step for practitioners to unlock higher storage savings, but they come with their own challenges. Of particular interest is their reliability , since wider stripes are prone to more simultaneous failures. We conduct a practically minded analysis of several popular and novel LRCs. We find that wide LRC reliability is a subtle phenomenon that is sensitive to several design choices, some of which are overlooked by theoreticians, and others by practitioners. Based on these insights, we construct novel LRCs called Uniform Cauchy LRCs , which show excellent performance in simulations and a 33% improvement in reliability on unavailability events observed by a wide LRC deployed in a Google storage cluster. We also show that these codes are easy to deploy in a manner that improves their robustness to common maintenance events. Along the way, we also give a remarkably simple and novel construction of distance-optimal LRCs (other constructions are also known), which may be of interest to theory-minded readers.

The dental technician as a member of the hypodontia multidisciplinary team, with practical considerations for anterior restoration design

Most patients seeking treatment for hypodontia will require prosthetic replacement of their missing teeth. This will be in the form of dentures, bridges and implant restorations. As these are created by one or more dental technicians who supports the clinical team, a close working relationship between these colleagues is likely to improve the quality of treatment outcome. This interaction will usually occur towards the end of the patient's treatment process, when definitive restorations are prescribed. However, appropriately trained and experienced dental technicians should be involved throughout the patient's treatment process as an integral part of the multidisciplinary team approach to effectively manage these patients.This paper describes the contribution of dental technicians to patient care with particular focus on communication between the restorative dentistry clinical team and the dental technician to improve the quality of anterior restorations. As missing maxillary lateral incisor teeth are a common presentation for this patient group, further technical detail relating to planning resin-bonded bridges for replacement of these teeth is included.

Analysis and prestress optimisation of membrane structures with optimal fabric alignment using modified energy minimisation

The use of light-weight tensile membrane structures (TMS) has become popular, particularly for covering vast areas. The behaviour of these structures when subjected to external actions is dependent on the initial shape, prestress and material property. The load analysis and optimisation of TMS are still challenging due to different factors including membrane wrinkling, choice of material fibre orientation and practical design considerations. This paper formulates the load analysis process by defining a modified energy functional with respect to the material fibre basis direction. The energy functional is directly minimised using a quasi-Newton solver addressing convergence issues. Improved algorithms to find the wrinkling criteria and direction are proposed. The choice of the material fibre direction and optimal seam partitioning based on the principal curvature are also developed. A practical optimisation framework for TMS is formulated based on available guidelines. The integrated methodology is successfully tested and demonstrated on a wide variety of case studies and benchmark problems. The optimal material fibre basis provides a stiffer (hence, more stable) structure and reduces the induced shear. The integrated solution along with the optimisation framework provide the end user with an effective method and tool for the design of TMS.