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Multifunctional Smart Grid Control based on Power Electronic Systems
No full textThere is a worldwide switch to electricity generation plants based on renewable energy sources(RES) to decarbonise electricity generation. In contrast to the fossil fuel based traditionalpower plants, power plants based on RES are widely distributed and often connected to thedistribution system operator (DSO) grid level, which leads to a structural change of theelectricity network. The rising numbers of installed RES and the high fluctuation of powergeneration increase the stress on this grid level. To improve the stability, reliability andefficiency of the DSO grid level, it is necessary to transfer and adapt ancillary service functionsknown from the transmission system operator (TSO) to the DSO grid level.To provide ancillary services at the DSO grid level under high fluctuations, unbalanced gridconditions and harmonic distortions, a new Multifunctional Energy and Power Server (MEPS)based on modern power electronic is introduced in this research. The system topology consistsof a series- and a parallel-connected inverter branch. This structure is known as the UnifiedPower Quality Conditioner (UPQC) and the Unified Power Flow Controller (UPFC), whichare used in active power filters and in power flow control in electrical grids. The systemapproach developed in this work for implementing grid service functions aims to combine thevarious approaches for this in a single system.The series branch consists of an inverter system connected by a transformer in series to theupstream network and is able to compensate for asymmetrical and harmonic distorted voltages.The parallel branch consists of a second inverter system, which is connected in parallel to thegrid and is able to compensate for asymmetrical and harmonic distorted currents. Incombination with a battery system, the parallel branch can also provide active power-basedfunctions, such as primary control and power fluctuation compensation. All these grid-specificdynamic control functions are implemented based on symmetrical components (SC) withindividual controller loops for the positive, negative and zero sequences in the fundamentaland harmonic frequency range. To use the SC for real-time control, all measured voltages andcurrents are separated into different harmonic components using the heterodyne method. Thecombination of the heterodyne method with the SC transformation allows for the individualand decoupled control under asymmetrical and harmonic distorted conditions.The simulation and application tests carried out during the research show, that unbalanced andharmonic distorted voltages and currents can be controlled selectively and in a decoupledmanner. By considering the effective impedance of the grid connection point individually, forevery harmonic frequency under control, allows for a stable operation and good transientresponse - also at difficult impedance characteristics, such as found at a 3-leg, 4-wire splitcapacitor inverter topology.Finally, several inverters were connected in parallel to increase the output power forexperiments under real grid conditions. The successful operation of a whole system consistingof several inverters demonstrates the flexibility and scalability of the approach. The control hasa positive impact on the capacity and stability of the examined grid area by reducing powerfluctuations and unsymmetrical and harmonic voltages and currents. The experiments confirmthe effectiveness of the decoupled control also under real grid conditions
Contemporary Marketing Solutions Strategies for Growth in a Competitive Consumer Landscape
No full textThe function of marketing is regarded as a mechanism that provides practical and theoretical solutions to contemporary businesses worldwide. In this edited book, a cast of international contributors address new and emerging areas within marketing, such as sustainable marketing, the circular economy, and how technologies drive and provide marketing solutions. Rather than exploring the issues, this book focuses on the solutions that these emerging areas provide for businesses. An essential resource for researchers and students, this book demonstrates how marketing activities are relevant to contemporary businesses, offering a state-of-the-art look at emerging trends
Palmyra Palm Shell (Borassus flabellifer) Properties Part 2: Insights Into Its Thermal and Mechanical Properties
No full textAdvancements in modern engineering design require materials that maintain thermal and mechanical stability under diverse conditions. To promote sustainability and eco-friendliness, researchers are increasingly exploring natural alternatives to synthetic fibers. Among bio-fibers, Borassus flabellifer fruit shell (husk), has no other uses than disposal or waste-to-energy in Bangladesh. While other parts of the plant, such as, the fruit and leaf stalks, are commonly utilized for fine and coarse fibers, the husk fiber remains underexplored. Hence, this study investigates exclusively the thermal properties of untreated Borassus husk fibers according to ASTM E2550 and ASTM E1269-11 standards and evaluates their curved specimens' mechanical properties using ASTM D2344 and ASTM D6415 standards. The findings reveal that raw Borassus husk fibers exhibit remarkable thermal stability, characterized by a higher char content and an elevated integral process decomposition temperature compared to the its fine and coarse fibers. During cellulose decomposition, the husk fibers demonstrate a specific heat capacity of 1.6 J/g°C, which surpasses that of coconut fibers. Additionally, mechanical testing indicates that the curved husk possesses competitive inter-laminar tensile strength and short-beam strength, comparable to glass fiber-reinforced polymers, curved woven glass/polyester composites and some bio-composites. Fracture surface analysis reveals a unique morphology, featuring non-uniform, cross-linked, and porous tubular structures, which contribute to the material's distinct thermal and mechanical properties. These results highlight the potential of untreated Borassus husk fibers as a viable material for engineering applications. Utilizing this underexplored resource could promote the cultivation and preservation of B. flabellifer trees, thereby encouraging sustainable development
Supporting children with child welfare concerns in Africa: Involving formal and informal systems–II
No full textPositive Psychology for Addiction Theory, Research and Application
No full textWith detailed examples of recent studies and practical guidance for practitioners, Positive Psychology for Addiction offers a comprehensive and holistic view of addiction recovery and challenges traditional deficit-focused approaches by advocating for strengths-based recovery methods
Enhancing Communication and Decision-Making with AI
No full textAs artificial intelligence (AI) revolutionizes communication and decision-making, its impact on industries and daily life grows. The AI boom has created an exciting opportunity for leaders to optimize human interaction, streamline decisions, and boost productivity across various fields. To compete at the highest level in today's fast paced environments, understanding the potential of these technologies is essential. Enhancing Communication and Decision-Making With AI explores cutting edge possibilities for improvement in AI-driven collaboration, predictive analytics, and ethical considerations. These chapters provide practical applications and insights for integrating AI into communication and decision-making to create compelling communications material and drive consumer action. Covering topics such as social media influence, competitive advantage frontiers, and computational intelligence, this book is designed with professionals, researchers, and students in mind
An Adaptive Conceptualisation of Artificial Intelligence and the Law, Regulation and Ethics
No full textThe description of a combination of technologies as ‘artificial intelligence’ (AI) is misleading. To ascribe intelligence to a statistical model without human attribution points towards an attempt at shifting legal, social, and ethical responsibilities to machines. This paper exposes the deeply flawed characterisation of AI and the unearned assumptions that are central to its current definition, characterisation, and efforts at controlling it. The contradictions in the framing of AI have been the bane of the incapacity to regulate it. A revival of applied definitional framing of AI across disciplines have produced a plethora of conceptions and inconclusiveness. Therefore, the research advances this position with two fundamental and interrelated arguments. First, the difficulty in regulating AI is tied to it characterisation as artificial intelligence. This has triggered existing and new conflicting notions of the meaning of ‘artificial’ and ‘intelligence’, which are broad and largely unsettled. Second, difficulties in developing a global consensus on responsible AI stem from this inconclusiveness. To advance these arguments, this paper utilises functional contextualism to analyse the fundamental nature and architecture of artificial intelligence and human intelligence. There is a need to establish a test for ‘artificial intelligence’ in order ensure appropriate allocation of rights, duties, and responsibilities. Therefore, this research proposes, develops, and recommends an adaptive three-elements, three-step threshold for achieving responsible artificial intelligence
Correction: Children's Health in London and Luton (CHILL) cohort: a 12-month natural experimental study of the effects of the Ultra Low Emission Zone on children's travel to school
No full textFollowing publication of the original article, the authors identified coding errors in the merging of datasets. Correcting these has resulted in an increased number of participants with complete covariate data. These corrections have had a minimal impact on the main findings; the magnitude of the effects and the primary conclusions remain supported
A Systematic Review of Substance Misuse Treatment Processes and Outcomes as Implemented in Prisons for Men in the UK
No full textWith a rising prison population, a substantial portion of whom are identified as substance misusers, it is important to understand the availability of treatment pathways, their successes and areas for improvement. Given the likely importance of national factors in criminal justice and substance use service provision, we chose to focus on one country.To review substance misuse treatment and outcomes for such treatments as implemented in British prisons for men.We conducted a mixed-methods systematic review, searching Ovid MEDLINE, Ovid Embase, APA PsycINFO, CINAHL Plus, Sociology Collection, Web of Science Core Collection and Social Science Premium Collection between 1 January 2000 and 5 June 2024. Included were empirical, peer-reviewed studies of processes and outcomes of UK male prison-based substance misuse programmes. Primary outcomes included changes in substance use, withdrawal symptoms and experiences of interventions, whereas secondary outcomes encompassed quality of life, locus of control and mental health. Because of study design heterogeneity, meta-analysis was not possible. Analysis followed JBI methodology with a convergent synthesis.Fourteen studies were included: 8 qualitative, 5 quantitative studies of which 3 were randomised control trials (RCTs) and 1 mixed-methods study, with a combined sample of 4037 participants engaged in opioid substitute treatment (OST) and/or psychosocial interventions. Four key themes emerged: the power of purposeful activity, strengthening support systems, bridging patient needs with treatment plans and, for those in opiate programmes, experiences and engagement with opioid substitution treatments.Participants articulated diverse treatment needs, highlighting the necessity of individualised and tailored reduction or maintenance plans. Treatment requires a comprehensive approach with the aim of facilitating effective social integration
Tunable Microstructured Silicon Waveguide Based Fabry-Perot Interferometric (Si-FPI) Label-Free Bio-Sensor for Cancer Detection
No full textThe compatibility of both silicon on insulator (SOI) and phase-changing materials such as vanadium dioxide (VO2) to the CMOS-based fabrication process gave birth to a new breed of sensing devices. These optical sensors are robust, small in size, and require less power and volume of precious analyte for analysis. In this paper, we propose and design a 2D linear Fabry-Perot(FP) label-free bio-sensor for different types of cancer cell detection. A silicon strip waveguide supported on silica with longitudinal ends terminated by the conductive VO2 behaves like a linear optical resonator. Sensing occurs when the evanescent tail of the guided mode interacts with the changing external refractive indices of different analytes leading to a shift in resonant frequency. The proposed model was simulated and analysed using the finite element method provided in COMSOL Multiphysics. Analysis performed for the 4m long resonator having 1.28m thick VO2 coating showed the maximum sensitivity of about 12.292 THz/RIU (101.44nm/RIU) for the cervical cancer. The overall sensitivity response of the investigated optical sensor is 12.312 THz/RIU (101.16 nm/RIU) with a correlation coefficient (R2) equal to 0.999. The detectable change in full width at half maximum (FWHM) of resonating mode from 3.6552 to 3.6960 THz for varying external refractive index (RI) makes the sensor immune to laser frequency fluctuations, a common source of noise in most of the resonant frequency shift-based sensing devices. The reported sensing structure has potential applications for highly sensitive label-free optical bio-sensing