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What does energy price uncertainty reveal about the global energy crisis?
No full textWe construct a Google search-based measure of energy price uncertainty (ENPU) that reflects oil, coal and natural gas price uncertainty. Using this index, we analyse the evolution of energy price uncertainty stemming from the first truly global energy crisis and model its impact on global stock markets. The ENPU measure reflects uncertainty beyond that quantified by the OVX and that associated with oil price shocks alone, confirming that the global energy crisis is driven by natural gas and coal price shocks. Stock markets are most responsive to ENPU during the period coinciding with the invasion of Ukraine whereas ENPU peaks around the sabotage of the Nord Stream pipeline. We interpret this asynchrony as evidence of markets adapting to the crisis, yielding insight into how economic agents process information. The limited impact of energy prices on returns, which we attribute to the supply-side nature of the crisis, suggests that the uncertainty transmission channel captures aspects of the crisis beyond energy price shocks alone. The impact of ENPU on global markets began declining from October 2022, suggesting that government interventions were at least partially effective. The insights and methodology expounded in this study will be of potential interest to market analysts, investors, policymakers and economists
Electrochemical energy storing performances of printed LaFeO3 coated with PEDOT: PSS for hybrid supercapacitors
Get PDFeveloping advanced smart energy storage devices demanded new functional materials to store energy effectively and deliver power quickly. In this work, we studied the energy-storing performance of perovskite material, lanthanum ferrite (LaFeO3), prepared by the solid-state reaction method. The screen-printed LaFeO3 and graphite electrodes are used to develop hybrid supercapacitors (HSCs) with KOH electrolyte. Varying the sintering temperature of the LaFeO3 perovskite electrode (800 °C, 900 °C, and 1000 °C) leads to changes in the surface and crystalline properties, which impact the electrochemical properties and overall energy-storing performance of the HSC. The surface of the LaFeO3 electrode is modified with organic conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS), which enhances the energy storage of the HSC. The developed HSC based on LaFeO3, sintered at 1000 °C and surface modified with PEDOT: PSS, exhibited a specific capacitance of 12.007 mF∙cm−2 at a current density of 0.075 mA∙cm−2. This value is two times higher than (5.874 mF∙cm−2) without the surface modification of LaFeO3 at 1000 °C. This study provides valuable insights into the electrochemical performances of the ABO3 perovskite (LaFeO3) electrodes for the next generation of portable energy storage devices
Attractive and repulsive visual aftereffects depend on stimulus contrast
Get PDFVisual perception has been described as a dynamic process where incoming visual information is combined with what has been seen before to form the current percept. Such a process can result in multiple visual aftereffects that can be attractive toward or repulsive away from past visual stimulation. A lot of research has been conducted on what functional role the mechanisms that produce these aftereffects may play. However, there is a lack of understanding of the role of stimulus uncertainty on these aftereffects. In this study, we investigate how the contrast of a stimulus affects the serial aftereffects it induces and how the stimulus itself is affected by these effects depending on its contrast. We presented human observers with a series of Gabor patches and monitored how the perceived orientation of stimuli changed over time with the systematic manipulation of orientation and contrast of presented stimuli. We hypothesized that repulsive serial effects would be stronger for the judgment of high-contrast than low-contrast stimuli, but the other way around for attractive serial effects. Our experimental findings confirm such a strong interaction between contrast and sign of aftereffects. We present a Bayesian model observer that can explain this interaction based on two principles, the dynamic changes of orientation-tuned channels in short timescales and the slow integration of prior information over long timescales. Our findings have strong implications for our understanding of orientation perception and can inspire further work on the identification of its neural mechanisms
Disentangling and hedging global warming risk: A machine learning approach
Get PDFAs global warming provokes increasing attention from investors, this study disentangles global warming risk (GWR) for investors by leveraging energy futures volatilities. This study derives GWR from energy futures using an extreme gradient boosting (XGB)-genetic programming (GP) framework. Our XGB-GP framework develops volatility forecasting models for GWR from selected energy futures markets identified by XGB as key contributors to global warming, surpassing traditional models in forecasting accuracy. The originality of the study rests on the pioneering integration of the XGB-GP framework in predicting climate risk, linking energy futures markets with climate risk management and enabling feasible climate-featured portfolio hedging. Our study also sheds new insights for policymakers to design carbon trading systems and carbon pricing mechanisms, as they can use relevant energy futures prices as a basis for carbon trading calibration
Reliable and Fair Trustworthiness Evaluation Protocol for Platoon Service Recommendation System
Get PDFAiming at the problems of the communication inefficiency and high energy consumption in vehicular networks, the platoon service recommendation systems (PSRS) are presented. Many schemes for evaluating the reputation of platoon head vehicles have been proposed to obtain and recommend reliable platoon head vehicles. However, these trustworthiness evaluation protocols for PSRS fail to achieve both reliability and fairness. In this paper, we first provide a reliable trustworthiness evaluation method to ensure that the reputation level of platoon head vehicle can be calculated by cloud service provider (CSP) with the help of key agreement mechanism and truth discovery technology. Besides, the semi-trusted entity CSP may maliciously tamper with the reputation level of the platoon head vehicle. Thus, we also provide a reputation level confirmation method to ensure the fairness of trustworthiness evaluation. Formal security proof and security analysis are provided to show that our trustworthiness evaluation protocol can achieve the goals of privacy protection, reliability, fairness and resistance to several security attacks. Experiments demonstrate that this protocol can save execution time and achieve reliable and fair trustworthiness evaluation for PSRS
Enhancing graduate employability – exploring the influence of experiential simulation learning on life skill development
Get PDFSkills and knowledge which increase the likelihood of university graduates finding employment is an increasingly important factor for higher education institutions. Even though subject matter expertise remains a primary objective, supporting students to build life skills that are desired by employers is essential to enhance graduate employability. Firstly, we draw on consultive interviews with 11 graduate recruiters to build a life skill ability scale. Through these interviews, we identify two constructs worth measuring (resilience and adaptability) not yet represented in extant life skill ability scales. Thereby contributing to life skills measures and their link to graduate employability. Secondly, this paper explores the influence of a team-based business simulation on the development of life skills at two higher education institutions in the UK for first- and fourth-year undergraduate students. Through a pre-survey and post-survey, this paper empirically finds that experiential learning by means of a team-based business simulation has an overwhelmingly positive influence on first-year students’ self-assessed life skill development as well as their course-specific subject matter expertise. Yet, the findings show less significant results for fourth-year students. This contributes to our understanding of business simulations as a pedagogical practice and its benefits for students beyond their education
“This Wall Does More for Mental Health than the Uni Does”: Theorising Toilet Graffiti as Safe House for Students
Get PDFDespite sometimes being considered unworthy of scholarly attention, the study of toilet graffiti, also known as latrinalia, has nevertheless garnered increasing interest among researchers. Graffiti writing still suffers from the stigma of being associated with transgression, vandalism, and a deviant subculture. However, findings from this study show that writing on the restroom wall can facilitate a unique form of communication among the writers. Drawing from semiotic linguistic landscaping and serendipity as methodological inspiration, this research explores data collected from a women's restroom at a UK university over a ten-month period. It examines how restroom users utilized the graffiti-covered wall as a safe house and a repository for their anxieties and concerns. The findings illustrate a palpable emotional connection to this specific wall, where writers seek and offer advice, share personal struggles, and provide mutual support to the extent that they see it as contributing more to their mental health than the university does. Through an analysis of the conversational threads present in the graffiti, this study underscores the potential for examining latrinalia within educational institutions to gain valuable and meaningful insights into the student body. The main implication is for educators to consider innovative, non-traditional ways of reaching out to students outside of the formal spaces of learning such as classrooms and libraries. This study, therefore, encourages us to reconsider toilet graffiti as potentially offering an additional or supplementary communication platform for individuals who might otherwise lack the confidence to express themselves openly through traditional means of soliciting feedback
Collaboration before competition: How smart city entrepreneurs co-create temporary ecosystems to build capacity for learning
Get PDFThis article explores how smart city entrepreneurs (SCEs) learn to address urban sustainability challenges with innovative digital products and services. SCEs embody social, digital, and urban entrepreneurialism features and play a pivotal role in advancing smart city development. But despite their importance, little is known about the knowledge, skills, and competencies required to become an SCE. Grounded in entrepreneurial learning theory, our study helps fill this gap. Using the city of Edinburgh, UK, as our empirical setting, we examine the learning process of 34 SCEs. Our findings offer three core contributions. First, we show that collaborative learning is a key driver of innovation in the smart city domain. SCEs significantly benefit from collaborative efforts rather than competitive strategies alone. Second, we show that these collaborations develop in temporary ecosystems that contribute to enhancing the innovative capacities of SCEs. Building on these findings, we expand entrepreneurial learning theory, highlighting the critical yet overlooked role of temporary ecosystems and intermediaries in stimulating collaboration and knowledge exchange among SCEs. Third, we provide practical recommendations for policymakers, emphasizing the importance of supporting the development of strategic learning capacities and diverse learning modalities for SCEs
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