Showing papers by "Xueping Li published in 2020"
TL;DR: In this paper, a two-stage stochastic programming model was developed to optimally place photovoltaic panels and green roofs under climate change uncertainty to maximize the overall profit from energy generated and saved.
Abstract: Photovoltaic (PV) panels directly convert sunlight into electricity; but, sunlight also heats the panels, negatively impacting their efficiency. Green roofs are vegetative layers grown on rooftops, mainly to provide added insulation on the roof to save energy. Green roofs also cool near-surface air temperature. Hence, the joint installation of PV panels and green roofs may potentially lead to higher efficiency of PV panels in certain climates. We develop a two-stage stochastic programming model to optimally place PV panels and green roofs under climate change uncertainty to maximize the overall profit from energy generated and saved. We calibrate the model using the literature, industry reports, and the data from different, at times conflicting, climate projections. We then conduct a case study for a mid-size city in the U.S., perform extensive sensitivity and robustness analyses and provide insights.
22 citations
TL;DR: A framework to simulate an aerial robot to acquire both aboveground and underground information for post-disaster SaR, which has potential to facilitate the understanding of the decision-making process in urban SaR and the training of future intelligent SaR robots.
Abstract: Unmanned aerial vehicles (UAVs), equipped with a variety of sensors, are being used to provide actionable information to augment first responders' situational awareness in disaster areas for urban search and rescue (SaR) operations. However, existing aerial robots are unable to sense the occluded spaces in collapsed structures, and voids buried in disaster rubble that may contain victims. In this study, we developed a framework, AiRobSim, to simulate an aerial robot to acquire both aboveground and underground information for post-disaster SaR. The integration of UAV, ground-penetrating radar (GPR), and other sensors, such as global navigation satellite system (GNSS), inertial measurement unit (IMU), and cameras, enables the aerial robot to provide a holistic view of the complex urban disaster areas. The robot-collected data can help locate critical spaces under the rubble to save trapped victims. The simulation framework can serve as a virtual training platform for novice users to control and operate the robot before actual deployment. Data streams provided by the platform, which include maneuver commands, robot states and environmental information, have potential to facilitate the understanding of the decision-making process in urban SaR and the training of future intelligent SaR robots.
20 citations
TL;DR: The results show that the affordability of green technologies and public awareness are the key drivers of the adoption of these technologies, which highlight the important role of the decision makers in impacting the diffusion rate.
17 citations
TL;DR: This research proposes a single-source capacitated facility location coverage problem (SS-CFLCP) to optimize the location, assignment and number of renewable distributed generators within a utility-based microgrid during a large-scale grid disturbance, where the microgrid is operating independent of the main grid.
Abstract: Microgrids are localized electric grids that can operate independent of the main grid and help strengthen grid resiliency by working alongside backup generators to maintain electricity supply in the event of a large-scale grid disturbance. This research proposes a single-source capacitated facility location coverage problem (SS-CFLCP) to optimize the location, assignment and number of renewable distributed generators (DGs) within a utility-based microgrid during a large-scale grid disturbance, where the microgrid is operating independent of the main grid. Traditional analytical techniques for DG placement within microgrids tend to focus on minimizing power losses, minimizing electric energy losses, improving voltage profile and maximizing cost savings. To deter from these traditional techniques, the proposed SS-CFLCP combines the facility location and location coverage problems, with an aim to minimize the following: total investment costs, total operation and maintenance cost, the distance traveled for electricity distribution, the power outage levels (unmet electricity demand) experienced due to a large-scale grid disturbance, and the levels of excess renewable penetration, which can cause reverse power flow issues that damage the main grid, within a network. Additionally, the proposed SS-CFLCP is modeled with a budgetary constraint for installing the DGs, making it a more practical and applicable model for a utility company. A case study using solar/photovoltaic-based DGs is used to show the effectiveness of the proposed model.
15 citations
TL;DR: Researchers explored symptoms of anxiety and depression when using a team-developed, patient-centered, and nurse-led intervention called Speak for Myself—Voice in five intensive care units at a Magnet status, university-affiliated medical center in East Tennessee.
Abstract: Effective two-way patient-provider communication is challenging and is even more difficult when patients are communication vulnerable. The results of being unheard and unacknowledged can contribute to negative feelings and may manifest as symptoms of anxiety and depression. Researchers explored symptoms of anxiety and depression when using a team-developed, patient-centered, and nurse-led intervention called Speak for Myself-Voice (formerly published as Speak for Myself) in five intensive care units at a Magnet status, university-affiliated medical center in East Tennessee. This was an equivalent control group design. The data were analyzed with a mixed-effect analysis of variance (between and within groups) with repeated measures to see if the treatment group changed differently than the control group across time (48 hours). This study report adds information about anxiety and depression in patients who are communication vulnerable and using communication technology.
8 citations
TL;DR: A multi-objective mathematical model is created based on a cooperative game between physicians and the central referral system to coordinate decisions towards system optimality and allows for intervening physicians’ perceived cost function and encourages them to accept requested transfers.
Abstract: This study investigates the collaboration framework of hospitals for consolidated healthcare systems. Although existing literature advocates the notion of strategic partnership in healthcare system...
8 citations
TL;DR: This paper proposes an integer programming formulation of the RDP, as well as a two-stage stochastic formulation using Benders decomposition, and proves the integrality of the second stage and proposes two algorithms based on the L -shaped method.
1 citations