15,575 research outputs found

    Assessing the Viability of Online Interruption Studies

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    Researchers have been collecting data online since the early days of the Internet and as technology improves, increasing numbers of traditional experiments are being run online. However, there are still questions about the kinds of experiments that work online, particularly over experiments with time-sensitive performance measures. We are interested in one time-sensitive measure specifically, the time taken to resume a task following an interruption. We ran participants through an archetypal interruption study online and in the lab. Statistical comparisons showed no significant differences in the time it took to resume following an interruption. However, there were issues with data quality that stemmed from participant confusion about the task. Our findings have implications for experiments that assess time-sensitive performance measures in tasks that require continuous attention

    Considerations about Continuous Experimentation for Resource-Constrained Platforms in Self-Driving Vehicles

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    Autonomous vehicles are slowly becoming reality thanks to the efforts of many academic and industrial organizations. Due to the complexity of the software powering these systems and the dynamicity of the development processes, an architectural solution capable of supporting long-term evolution and maintenance is required. Continuous Experimentation (CE) is an already increasingly adopted practice in software-intensive web-based software systems to steadily improve them over time. CE allows organizations to steer the development efforts by basing decisions on data collected about the system in its field of application. Despite the advantages of Continuous Experimentation, this practice is only rarely adopted in cyber-physical systems and in the automotive domain. Reasons for this include the strict safety constraints and the computational capabilities needed from the target systems. In this work, a concept for using Continuous Experimentation for resource-constrained platforms like a self-driving vehicle is outlined.Comment: Copyright 2017 Springer. Paper submitted and accepted at the 11th European Conference on Software Architecture. 8 pages, 1 figure. Published in Lecture Notes in Computer Science vol 10475 (Springer), https://link.springer.com/chapter/10.1007/978-3-319-65831-5_

    Microgrids & District Energy: Pathways To Sustainable Urban Development

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    A microgrid is an energy system specifically designed to meet some of the energy needs of a group of buildings, a campus, or an entire community. It can include local facilities that generate electricity, heating, and/or cooling; store energy; distribute the energy generated; and manage energy consumption intelligently and in real time. Microgrids enable economies of scale that facilitate local production of energy in ways that can advance cost reduction, sustainability, economic development, and resilience goals. As they often involve multiple stakeholders, and may encompass numerous distinct property boundaries, municipal involvement is often a key factor for successful implementation. This report provides an introduction to microgrid concepts, identifies the benefits and most common road blocks to implementation, and discusses proactive steps municipalities can take to advance economically viable and environmentally superior microgrids. It also offers advocacy suggestions for municipal leaders and officials to pursue at the state and regional level. The contents are targeted to municipal government staff but anyone looking for introductory material on microgrids should find it useful

    Immunogenicity of personalized dendritic-cell therapy in HIV-1 infected individuals under suppressive antiretroviral treatment:interim analysis from a phase II clinical trial

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    BACKGROUND: We developed a personalized Monocyte-Derived Dendritic-cell Therapy (MDDCT) for HIV-infected individuals on suppressive antiretroviral treatment and evaluated HIV-specific T-cell responses. METHODS: PBMCs were obtained from 10 HIV(+) individuals enrolled in trial NCT02961829. Monocytes were differentiated into DCs using IFN-α and GM-CSF. After sequencing each patient’s HIV-1 Gag and determining HLA profiles, autologous Gag peptides were selected based on the predicted individual immunogenicity and used to pulse MDDCs. Three doses of the MDDCT were administered every 15 days. To assess immunogenicity, patients’ cells were stimulated in vitro with autologous peptides, and intracellular IL-2, TNF, and interferon-gamma (IFN-γ) production were measured in CD4(+) and CD8(+) T-cells. RESULTS: The protocol of ex-vivo treatment with IFN-α and GM-CSF was able to induce maturation of MDDCs, as well as to preserve their viability for reinfusion. MDDCT administration was associated with increased expression of IL-2 in CD4(+) and CD8(+) T-cells at 15 and/or 30 days after the first MDDCT administration. Moreover, intracellular TNF and IFN-γ expression was significantly increased in CD4(+) T-cells. The number of candidates that increased in vitro the cytokine levels in CD4(+) and CD8(+) T cells upon stimulation with Gag peptides from baseline to day 15 and from baseline to day 30 and day 120 after MDDCT was significant as compared to Gag unstimulated response. This was accompanied by an increasing trend in the frequency of polyfunctional T-cells over time, which was visible when considering both cells expressing two and three out of the three cytokines examined. CONCLUSIONS: MDDC had a mature profile, and this MDDCT promoted in-vitro T-cell immune responses in HIV-infected patients undergoing long-term suppressive antiretroviral treatment. Trial registration NCT02961829: (Multi Interventional Study Exploring HIV-1 Residual Replication: a Step Towards HIV-1 Eradication and Sterilizing Cure, https://www.clinicaltrials.gov/ct2/show/NCT02961829, posted November 11th, 2016) SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12981-021-00426-z

    Current and forthcoming issues in the South African electricity sector

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    One of the contentious issues in electricity reform is whether there are significant gains from restructuring systems that are moderately well run. South Africa's electricity system is a case in point. The sector's state-owned utility, Eskom, has been generating some of the lowest-priced electricity in the world, has largely achieved revenue adequacy, and has financed the bulk of the government's ambitious electrification program. Moreover, the key technical performance indicators of Eskom's generation plants have reached world-class levels. Yet the sector is confronted today with serious challenges. South Africa's electricity system is currently facing a tight demand/supply balance, and the distribution segment of the industry is in serious financial trouble. This paper provides a careful diagnostic assessment of the industry and identifies a range of policy and restructuring options to improve its performance. It suggests removing distribution from municipal control and privatizing it, calls for vertical and horizontal unbundling, and argues that the cost-benefit analysis of different structural options should focus on investment incentives and not just current operating efficiency.Energy Production and Transportation,Electric Power,Environment and Energy Efficiency,Energy and Environment,Infrastructure Economics

    Investment in Sustainable Development: A UK Perspective on the Business and Academic Challenges

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    There are many legislative, stakeholder and supply chain pressures on business to be more ‘sustainable’. Universities have recognised the need for graduate knowledge and understanding of sustainable development issues. Many businesses and universities have responded and introduced Sustainable Development models into their operations with much of the current effort directed at climate change. However, as the current worldwide financial crisis slowly improves, the expectations upon how businesses operate and behave are changing. It will require improved transparency and relationships with all stakeholders, which is the essence of sustainable development. The challenges and opportunities for both business and universities are to understand the requirements of sustainable development and the transformation that is required. They should ensure that knowledge is embedded within the culture of the organisation and wider society in order to achieve a sustainable future

    Technical and economic feasibility of a microgrid for a fire station in Humboldt County, California.

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    Microgrids are emerging as a promising solution to unreliable grid energy. Today, California is not only witnessing grid resiliency challenges from natural disasters such as wildfires, earthquakes, floods and heatwaves, but it is also seeking to green the grid and bring more renewables online. For example, Humboldt County, where this project is focused, has recently experienced an earthquake of 6.4M (on December 22nd, 2022), which shut down the regional grid for ~20 hours. Microgrid adoption enables critical facilities to operate seamlessly. The Humboldt Bay Fire Station (HBFS) No.1 is one such example, where first responders work to protect citizens against emergencies, be it emergency medical services (EMS) operations or fire rescue or even helping in restoration of power lines. This study involves a techno-economic analysis of a microgrid design that could support efficient and seamless operations for the fire station as it serves the people of Humboldt County during emergencies. A clean energy microgrid for the station aligns with the Humboldt County GHG emission target to reach net zero by 2030, and could provide resilient power to their general and critical loads during regular operations and emergencies. The recommended microgrid for the HBFS No. 1 facility includes a 70-kW photovoltaic (PV) array and a 90 kW/360 kWh battery energy storage system (BESS). The project cost ranges from 300kto300k to 600k (depending upon the level of investment tax credits (ITC) the microgrid project would get). It provides 51-day resiliency in the best case and 28-hour resiliency in the worst case depending upon the weather condition. The system would also reduce greenhouse gas emissions from electricity use at the station by over 98% annually. Considering the potential availability of incentives and the value of resiliency (VoR), the microgrid project for HBFS No.1 demonstrates promising economic feasibility results. The next steps involve further evaluation of the project\u27s financial viability, engaging with relevant stakeholders to secure funding, and proceeding with the detailed design and implementation phases of the microgrid
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