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  1. Abstract
    Data set that was used to determine the frequency each of 4 key words (public engagement, education, outreach, or science communication) in the title or abstract of published papers in Freshwater Science (formerly the Journal of the North American Benthological Society) and oral presentations (talks) at the annual Society for Freshwater Science meetings from 1997 to 2019. Does not include any data on talks for 2013-2014 because they were not published during those years.
    Methods
    The dataset was collected by reviewing abstracts in the journal Freshwater Science (formerly the Journal of North American Benthological Society [JNABS]) from 1997 toMore>>
  2. Free, publicly-accessible full text available November 1, 2023
  3. Free, publicly-accessible full text available September 1, 2023
  4. Abstract Arrays of flexible polymer piezoelectric film cantilevers that mimic grass or leaves is a prospective idea for harvesting wind energy in urban areas, where the use of traditional technologies is problematic due to low wind velocities. Conversion of this idea into an economically attractive technology depends on various factors including the shape and dimensions of individual films to maximize generated power and to minimize associated costs of production, operation, and maintenance. The latter requirement can be satisfied with rectangular films undergoing flutter in ambient air. Flexible piezoelectric films that displace due to low forces and can convert mechanical energymore »into electrical energy are ideal for this application. The goal of the presented study is to determine the key dimensions of the piezoelectric film to enhance generated power within the wind range characteristic for urban areas from 1.3 to 7.6 m/s. For this purpose, experiments were conducted in a wind tunnel using piezoelectric polymer films of polyvinylidine fluoride with the length, width, and thickness varying in the ranges of 32–150, 16–22, and 40–64 μm, respectively. Voltage and power outputs for individual samples were measured at wind speeds ranging from 0.5 to 16.5 m/s. Results demonstrated that a single film could produce up to 0.74 nW and that the optimal film dimensions are 63 mm × 22 mm × 40 μm (from considered samples) for the wind energy harvesting in urban areas. Further improvement in power production can be expected when using films with reduced thickness, low elastic modulus, and increased length, and by assembling films in arrays.« less
    Free, publicly-accessible full text available July 1, 2023
  5. In this research, data from 36 countries from 2013 to 2018 were used to examine the factors influencing CO 2 emissions in Islamic countries, focusing on the impact of Islamic financial growth. The spatial econometric technique estimation findings indicate that there is no geographical association between CO 2 emissions in the analyzed countries. The test findings establish the existence of the Kuznets hypothesis for the environment. Additionally, trade openness and increased energy usage have resulted in an increase in CO 2 emissions. The impacts of traditional financial development factors, such as financial market and financial institution variables, were examined inmore »this research. The findings indicate that the two variables have no direct and substantial influence on CO 2 emissions and that their significant effect on CO 2 emissions appears only when their nonlinear and spillover effects on energy consumption and economic growth are included. Additionally, the growth of financial institutions is inversely proportional to the intensity of carbon emissions. The results indicate that while the development of financial markets and institutions results in a significant increase in CO 2 emissions, the negative coefficient of the interaction between financial development and energy consumption indicates that financial development ensures energy efficiency, which reduces the intensity of carbon emissions. The findings indicate that the expansion and depth of Islamic finance, as measured by total assets, asset quality, earnings, and efficiency of Islamic banks, can result in a nonlinear increase in CO 2 emissions with a U-shaped relationship. The study of spillover effects demonstrates that in addition to their direct and positive effects on CO 2 emissions, the increase in Islamic social responsibility and consumer education, and awareness about Islamic banking reduce the enhancing effects of energy consumption on greenhouse gas emissions.« less
    Free, publicly-accessible full text available April 14, 2023
  6. User authentication plays an important role in securing systems and devices by preventing unauthorized accesses. Although surface Electromyogram (sEMG) has been widely applied for human machine interface (HMI) applications, it has only seen a very limited use for user authentication. In this paper, we investigate the use of multi-channel sEMG signals of hand gestures for user authentication. We propose a new deep anomaly detection-based user authentication method which employs sEMG images generated from multi-channel sEMG signals. The deep anomaly detection model classifies the user performing the hand gesture as client or imposter by using sEMG images as the input. Differentmore »sEMG image generation methods are studied in this paper. The performance of the proposed method is evaluated with a high-density hand gesture sEMG (HD-sEMG) dataset and a sparse-density hand gesture sEMG (SD-sEMG) dataset under three authentication test scenarios. Among the sEMG image generation methods, root mean square (RMS) map achieves significantly better performance than others. The proposed method with RMS map also greatly outperforms the reference method, especially when using SD-sEMG signals. The results demonstrate the validity of the proposed method with RMS map for user authentication.« less
    Free, publicly-accessible full text available April 1, 2023
  7. Abstract Answer Set Planning refers to the use of Answer Set Programming (ASP) to compute plans , that is, solutions to planning problems, that transform a given state of the world to another state. The development of efficient and scalable answer set solvers has provided a significant boost to the development of ASP-based planning systems. This paper surveys the progress made during the last two and a half decades in the area of answer set planning, from its foundations to its use in challenging planning domains. The survey explores the advantages and disadvantages of answer set planning. It also discussesmore »typical applications of answer set planning and presents a set of challenges for future research.« less
    Free, publicly-accessible full text available April 1, 2023
  8. Modern smart grid systems exploit a two-way interaction paradigm between the utility and the electricity user and promote the role of prosumer, as a new user type, able to generate and sell energy, or consume energy. Within such a setting, the prosumers and their interactions with the microgrid system become of high significance for its efficient operation. In this article, to model the corresponding interactions, we introduce a labor economics-based framework by exploiting the principles of contract theory, that jointly achieves the satisfaction of the various interacting system entities, i.e., the microgrid operator (MGO) and the prosumers. The MGO offersmore »personalized rewards to the sellers and buyers, to incentivize them to sell and purchase energy, respectively. To provide a stable and efficient operation point, while aiming at jointly satisfying the profit and requirements of the involved competing parties, optimal personalized contracts, i.e., rewards and amount of sold/purchased energy, are determined, by formulating and solving contract-theoretic optimization problems between the MGO and the sellers or buyers. The analysis is provided for both cases of complete and incomplete information availability regarding the prosumers’ types. Detailed numerical results are presented to demonstrate the operation characteristics of the proposed framework under diverse scenarios.« less
    Free, publicly-accessible full text available March 28, 2023
  9. Filtration-based (FB) power/current allocation of battery-supercapacitor (SC) hybrid energy storage systems (HESSs) is the most common approach in DC microgrid (MG) applications. In this approach, a low-pass or a high-pass filter is utilized to decompose the input power/current of HESS into high-frequency and low-frequency components and then assign the high-frequency parts to SC. Moreover, to avoid the state of charge violation (SoC) of SC, this approach requires a rule-based supervisory controller which may result in the discontinuous operation of SC. This paper first provides a small-signal stability analysis to investigate the impact of an FB current allocation system on themore »dynamic stability of an islanded DC MG in which a grid-forming HESS supplies a constant power load (CPL). Then, it shows that the continuous operation of SC is essential if the grid-forming HESS is loaded by large CPLs. To address this issue, this paper proposes a model predictive control (MPC) strategy that works in tandem with a high-pass filter to perform the current assignment between the battery and SC. This approach automatically restores the SoC of SC after sudden load changes and limits its SoC variation in a predefined range, so that ensure the continuous operation of SC. As a result, the proposed FB-MPC method indirectly enables the MG’s proportional-integral (PI) voltage controller to operate with higher gain values leading to better transient response and voltage quality. The performance of the proposed approach is then validated by simulating the system in MATLAB/Simulink.« less
    Free, publicly-accessible full text available February 28, 2023
  10. Anthropogenic activities are responsible for greenhouse gas emissions, causing extreme events like soil erosion, droughts, floods, forest fires and tornadoes. Fossil fuel consumption produces CO2, and trapping heat is the major reason for a rapid increase in global temperature, and electricity generation is responsible for 25% of greenhouse gas emissions. Fossil fuel consumption, CO2 emissions and their adverse impact have become the focus of efforts to mitigate climate change vulnerability. This study explores empirical determinants of vulnerability to climate change such as ecosystem, food, health and infrastructure. The sustainable use of energy is necessary for development, and a source ofmore »response to climate change. The present study focuses on renewable energy consumption to determine climate vulnerability in G7 countries between 1995 and 2019. The panel ARDL approach showed that the renewable to non-renewable energy mix showed a quadratic effect on vulnerability, whereby a minimum threshold of renewable energy is required to witness a reduction in food, health and infrastructure vulnerability. Other results indicate that trade openness and development expenditures reduce health vulnerability. Development expenditures also decrease ecosystem vulnerability, while trade openness increases it. However, both of these variables increase infrastructure vulnerability. Avoiding severe food and water crises requires investment to tackle climate change, conserve energy and water resources, reform global trade and food markets, and adapting and adopting climate-resilient responses to change.« less
    Free, publicly-accessible full text available February 1, 2023