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Kabul, 2021 - The Taliban Overtakes Kabul
No full textThe sudden collapse of the Government of the Islamic Republic of Afghanistan (GIRoA) in the face of the Taliban advance of July-August 2021, stands as a key moment of national embarrassment to the two intervening powers with the greatest exposure there: the US and the UK. Despite ample warning from multiple sources that the Taliban were making rapid advances, and that large parts of the Afghan National Army (ANA) and Police (ANP) were evaporating before the onslaught, neither the US nor the UK made adequate plans to deal with the collapse of GIRoA and the implications of that to their remaining interests in the country. Strategic intelligence analysis of the situation by US and UK analysts predicted state collapse, but generally on a longer timeline. Tactical warning was also lacking: the rapidity of the situation, and the inability of the two governments to understand and adapt to the situation, lead to chaotic evacuations of Afghanistan on terms dictated by the Taliban. The case is one of some accurate strategic warning married to tactical intelligence failure, leading to policy failure and surprise. It is both Type I and Type II failure
Identifying socio-cognitive beliefs of eating in moderation in adults in the UK and Jordan
Get PDFThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonThis thesis aims to understand and influence the socio-cognitive beliefs towards moderate eating in adults in the UK and Jordan, to aid public health interventions for obesity. It begins with a systematic review identifying key factors in healthy eating habits, focusing on intrapersonal elements like self-efficacy and risk perception. The research then dives into qualitative and quantitative studies in the UK and Jordan to specifically explore beliefs about eating in moderation. It utilizes the "I-change model" as a theoretical framework. The goal is to provide tailored information for public health programs in these countries, targeting beliefs specific to their populations. The thesis concludes by discussing the contributions of each study, finding overarching themes for future research, and the importance of intervention mapping in designing effective public health programs.
The thesis uncovered several key findings. In the UK and Jordan, beliefs and perceptions about healthy eating, particularly eating in moderation, varied significantly. The research highlighted the importance of socio-cognitive factors like self-efficacy and risk perception in shaping these beliefs. It also revealed cultural differences in attitudes towards obesity and eating habits. The results from both countries provided valuable insights for designing targeted public health interventions, emphasizing the need for culturally sensitive approaches in promoting healthier eating habits. These findings contribute significantly to understanding the complex interplay of socio-cognitive factors in dietary behaviors
Maintaining Ukraine’s Grid Reliability under Rapid Growth of Renewable Electricity Share: Challenges in the Pre-War, War-Time, and Post-War Periods
Get PDFThe paper deals with the problems of maintaining Ukraine’s grid reliability under high renewable electricity penetration and improving state policy measures to accelerate sustainable energy transition in the post-war period. Promoting renewable energy in Ukraine increased renewable electricity share in the country’s electricity mix to 13.8% in 2021. However, such growth became critical for Ukraine’s electric power system. Due to its inflexibility, the lack of balancing and energy storage capacities, adding significant amounts of renewable electricity to the grid created severe problems. Further renewable energy development required serious reforming policy measures, but the Russian invasion prevented introducing relevant legislative changes. At the same time, the war had an unprecedented impact on the Ukrainian energy sector, resulting in the damage of more than 50% of the energy infrastructure. Considering global trends towards decarbonisation and achieving climate neutrality, reconstructing Ukraine’s electric power sector will be based on the large-scale involvement of renewable energy technologies. Given this, based on the study of the trends in renewable energy development in the pre-war and war-time periods and the analysis of the shortcomings of the state energy policy, the paper examines the required measures for fostering resilient reconstruction of Ukraine's electric power sector.The publication contains the results of research carried out under the project “Development of a software com-plex for accurate forecasting of electricity generation by solar power plants to minimize the green-coal paradox” (No. 0123U102760) and the fellowships of the British Academy “Exploring pathways to Ukraine’s zero-car-bon, equitable, and secure energy future” and “Examining net zero policy and regulation in energy markets across Europe”
Surface roughness: capturing rough-bed river diversity
Get PDFMeeting abstract presented at EGU General Assembly 2024, Vienna, Austria, 14-19 April 2024.Channel geometry and bed surface roughness modulate the flow resistance of river channels, which is fundamental to the conveyance of water and sediment. In rough-bed rivers, where the flow is shallow relative to roughness height, there is notable uncertainty in flow resistance calculations based on sediment percentiles (D50 or D84) or the standard deviation of bed elevations. A new approach based on alternative surface roughness metrics is required to encompass the diversity of rough-bed rivers and to identify alternative metrics capable of characterising their complex topography and elements including boulders and bedrock.
Here, geostatistical analysis is conducted for 20 rough-bed river reaches with varying channel characteristics (channel geometry, bedrock exposure, sediment grainsize, boulder density, and lithology). Multi-scale elevation- and gradient-based surface roughness metrics are extracted from high-resolution digital elevation modes and analysed to determine the most applicable metrics to fully define rough-bed rivers. Statistical analysis includes application of correlation analysis, Principal Component Analysis (PCA), and Hierarchical clustering. The results reveal that a complete description of the topographic properties of rough-bed rivers requires the use of multiple roughness metrics. Research outside Geomorphology has found that elevation skewness and frontal solidity are two metrics that can comprehensively define surface roughness. We find these metrics are capable of distinguishing between channels with differing characteristics, including bedrock or boulders, across multiple scales. The results provide a framework to support further research on the topographic controls on flow resistance and offer insights that advance topographic analysis across geomorphology
Validity of a wrist-worn consumer-grade wearable for estimating energy expenditure, sedentary behaviour and physical activity in manual wheelchair users with spinal cord injury
Get PDFData availability statement: The datasets supporting the conclusions of this article are available in Figshare (https://figshare.com/s/e1db69ec9f38bdd1ab16), DOI: 10.17633/rd.brunel.24551791.Purpose:
To evaluate the validity of a consumer-grade wearable for estimating energy expenditure, sedentary behaviour, and physical activity in manual wheelchair users with spinal cord injury (SCI).
Materials and methods:
Fifteen manual wheelchair users with SCI (C5-L1, four female) completed activities of daily living and wheelchair propulsion (2–8 km·h−1). Wrist-worn accelerometry data were collected using consumer-grade (z-Track) and research-grade (ActiGraph GT9X) devices. Energy expenditure was measured via indirect calorimetry. Linear regression was used to evaluate the prediction of criterion metabolic equivalent of task (MET) by each accelerometer’s vector magnitude (VM). Area under the receiver operating characteristic curve (ROC-AUC) evaluated the accuracy of VM for discriminating between physical activity intensities and for identifying accelerometer cut-points.
Results:
Standardised β-coefficients for the association between z-Track and ActiGraph VM for criterion MET were 0.791 (p < 0.001) and 0.774 (p < 0.001), respectively. The z-Track had excellent accuracy for classifying time in sedentary behaviour (ROC-AUC = 0.95) and moderate-to-vigorous physical activity (ROC-AUC = 0.93); similar values to the ActiGraph (ROC-AUC = 0.96 and 0.88, respectively). Cut-points for the z-Track were ≤37 g·min−1 for sedentary behaviour and ≥222 g·min−1 for moderate-to-vigorous physical activity.
Conclusions:
This study supports the validity of a consumer-grade wearable to measure sedentary time and physical activity in manual wheelchair users with SCI.No external funding was received in support of the stud
Solving Two-stage Quadratic Multiobjective Problems via Optimality and Relaxations
Get PDFMathematics Subject Classification: 49K99; 65K10; 90C29; 90C46.This paper focuses on the study of robust two-stage quadratic multiobjective optimization problems. We formulate new necessary and sufficient optimality conditions for a robust two-stage multiobjective optimization problem. The obtained optimality conditions are presented by means of linear matrix inequalities and thus they can be numerically validated by using a semidefinite programming problem. The proposed optimality conditions can be elaborated further as second-order conic expressions for robust two-stage quadratic multiobjective optimization problems with separable functions and ellipsoidal uncertainty sets. We also propose relaxation schemes for finding a (weak) efficient solution of the robust two-stage multiobjective problem by employing associated semidefinite programming or second-order cone programming relaxations. Moreover, numerical examples are given to demonstrate the solution variety of our flexible models and the numerical verifiability of the proposed schemes.Australian Research Council under Discovery Program grant DP200101197
The Interplay Between Social Entrepreneurial Knowledge, Prosocial Motivation, Perceived Access to Finance and Social Entrepreneurial Intention
Get PDFBuilding on insights from human capital and self-determination theories, this study examines the chain mediating effect of prosocial motivation and perceived access to finance in the linkage between social entrepreneurial knowledge and social entrepreneurial intention. Using survey data from 330 university students from Nigeria, the findings show that social entrepreneurial knowledge is positively linked with social entrepreneurial intention, and that prosocial motivation mediates this relationship. Perceived access to finance also positively intervened in the link between social entrepreneurial knowledge and social entrepreneurial intention. Finally, prosocial motivation and perceived access to finance had a significant serial mediating effect on the influence of social entrepreneurial knowledge on social entrepreneurial intention of university students. The study concludes with academic and practical implications for educators and policymakers in under-researched Sub-Saharan African contexts like Nigeria
Blockchain Technology Characteristics Essential for the Agri-food Sector: A Systematic Review
Get PDFData availability: Data will be made available on request.Blockchain is seen as a disruptive fundamental technology that will transform agri-food sectors in the near future. Blockchain is a digital, immutable, decentralized ledger of transactions that is replicated and distributed throughout the chain of computer systems on the blockchain's network. This systematic review examines the literature to identify the enabling characteristics of blockchain technology that support its application in the agri-food sectors. The literature reviewed indicated essential characteristics such as transparency, immutability, redundancy, versatility, automation, and remittance. Among these features, immutability and automation have a salient role in the current implementation, particularly in food traceability. However, the application of blockchain in the agri-food sector is not without controversies. More research is needed regarding technical improvement and its environmental impact.Swedish University of Agricultural Sciences, Sweden, by a scholarship from L Nannesson's foundation, grant number Dnr SLU.ua.2019.3.1.5–617
Distributed Kalman Filtering Under Two-Bitrate Periodic Coding Strategies
Get PDFThis paper is concerned with the problem of distributed Kalman filtering over sensor networks under two-bitrate periodic coding strategies. Initially, the optimal estimates for sensor individuals are acquired using the conventional Kalman filter. Subsequently, the information pair, consisting of the local estimate and the corresponding covariance, is exchanged among their immediate neighbors to achieve cooperative estimation. Due to the constrained network bandwidth, a vector/matrix quantization approach is formulated to quantize the information pair. The output of this quantization establishes a conservative bound for the actual covariance. A two-bitrate periodic coding strategy is proposed, where the encoded bits of the quantizer outputs are divided into two separate parts, namely the most significant and least significant bits, following a periodic transmission principle. It is demonstrated that the estimation preserves a consistency property over the sensor networks as the reported error covariance always serves as an upper bound for the actual error covariance. It is shown that the mean-square estimation errors are bounded when certain conditions regarding collective observability and network connectivity are satisfied. Finally, the effectiveness of the proposed algorithm is verified through a numerical example
Weight of evidence evaluation of the metabolism disrupting effects of triphenyl phosphate using an expert knowledge elicitation approach
Get PDFData availability:
Data will be made available on request.Supplementary data are available online at: https://www.sciencedirect.com/science/article/pii/S0041008X24001935#s0160 .Identification of Endocrine-Disrupting Chemicals (EDCs) in a regulatory context requires a high level of evidence. However, lines of evidence (e.g. human, in vivo, in vitro or in silico) are heterogeneous and incomplete for quantifying evidence of the adverse effects and mechanisms involved. To date, for the regulatory appraisal of metabolism-disrupting chemicals (MDCs), no harmonised guidance to assess the weight of evidence has been developed at the EU or international level. To explore how to develop this, we applied a formal Expert Knowledge Elicitation (EKE) approach within the European GOLIATH project. EKE captures expert judgment in a quantitative manner and provides an estimate of uncertainty of the final opinion. As a proof of principle, we selected one suspected MDC -triphenyl phosphate (TPP) - based on its related adverse endpoints (obesity/adipogenicity) relevant to metabolic disruption and a putative Molecular Initiating Event (MIE): activation of peroxisome proliferator activated receptor gamma (PPARγ). We conducted a systematic literature review and assessed the quality of the lines of evidence with two independent groups of experts within GOLIATH, with the objective of categorising the metabolic disruption properties of TPP, by applying an EKE approach. Having followed the entire process separately, both groups arrived at the same conclusion, designating TPP as a “suspected MDC” with an overall quantitative agreement exceeding 85%, indicating robust reproducibility. The EKE method provides to be an important way to bring together scientists with diverse expertise and is recommended for future work in this area.European Union's Horizon 2020 research and innovation program under grant agreement No 825489 (“GOLIATH”)
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