bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and performance optimization of a tri‐generation energy hub considering demand response programs
Authors: Taheri Bahman , Foroud Asghar Akbari , Jabari Farkhondeh 
Published: November 2022

AbstractThe design and development of renewable energy resources‐based poly‐generation microgrids have recently increased to supply multiple demands such as cool, heat, and power as well as mitigate pollutants improving efficiency. This paper aims to develop a combined cooling, heating, and power production network integrating photovoltaic panels (PVs), wind and gas turbines, a battery, an ice bank tank, a heater, an electrical chiller, a thermal energy storage medium. In this tri‐generation facility, natural gas is utilized for district heating and fueling the gas turbine power generation cycle. The local power distribution system in combination with the output powers of PVs, wind and gas turbines is used to directly supply the electrical appliances, ice maker process, and chiller as well as charge the battery storage unit. Moreover, the air/water‐cooled chiller procures the cooling flux for a benchmark microgrid. Its heating energy requirement is also provided by the gas‐fired heater, the flue gases of the gas turbine, and the thermal storage medium. A mixed integer linear programming problem is coded using a generalized algebraic modeling system (GAMS) to minimize daily operating costs and emissions. Simulations are examined and analyzed over a 24‐h study horizon on a sample summer day. Time‐of‐use energy rates and RTPs are considered two strategic demand response schemes to investigate the cost‐effectiveness capability of the gas‐power nexus model. The proposed approach is coded using a GAMS to confirm its effectiveness and cost‐environ benefits in four cases with and without heat/cool/electrical storage units considering time‐of‐use energy rates and real‐time prices.
Performance prediction of centrifugal compressor based on a new volute loss model and corrected theoretical work
Authors: Qingyi Sai , Jian Chen , Bo Zhang 
Published: November 2022

AbstractPerformance prediction plays an important role in the predesign stage of centrifugal compressors. A set of loss models is usually selected and grouped to fulfill the above prediction. To improve the defects of traditional prediction, we modified the outlet velocity and slip coefficient of the impeller by means of the energy average method to obtain theoretical work. A new volute loss model is proposed to replace the traditional semiempirical loss model by adopting a suitable loss model for each flow passage component. A proper performance prediction method is established for the centrifugal compressor studied in this paper. The overall performance of a single‐stage centrifugal compressor is predicted and compared with experimental and numerical simulation results. It is found that the prediction method proposed can better predict the overall performance of the centrifugal compressor. And the volute loss is the third largest loss after impeller loss.
Experimental validation of fuzzy type‐2 against type‐1 scheme applied in DC/DC converter integrated to a PEM fuel cell system
Authors: Napole Cristian , Derbeli Mohamed , Barambones Oscar 
Published: November 2022

AbstractThis research presents and compares the outcomes of experimental implementations of different fuzzy logic control structures for a proton exchange membrane fuel cell (PEMFC). These devices are well known for their capability to transform chemical energy into electrical with low emissions. Commonly, a PEMFC has a linkage with a boost converter which allows a suitable end‐user voltage through a nonlinear control law. Hence, the contribution in this sense is the experimental comparison of two fuzzy logic strategies known as type‐1 and type‐2 that were implemented in a PEMFC system. The approaches were embedded in a control board dSPACE 1102 which also has the capability to acquire data. The contrast of results showed capabilities improvement against disturbances in terms of error reduction, control signal, and robustness.
Investigation of thermal efficiency for subcritical ORC and TFC using super dry working fluids
Authors: Ahmed Aram M. , Imre Attila R. 
Published: November 2022

AbstractEfficiency is a crucial factor for power cycles. Generally, in the same temperature range, the cycle efficiency for a basic organic Rankine cycle (ORC) is higher than a similar trilateral flash cycle (TFC) for almost all working fluids and heat source/heat sink temperature pairs. According to some recent results, by using super dry working fluids, the thermal efficiency of TFC can outperform its ORC counterpart at high temperatures. This study performed the thermodynamics analysis using three dry working fluids with subcritical basic ORC and TFC with zero to partial recuperated heat ratio. The results showed that using recuperative heat exchange effectively contributes to increasing the efficiency of ORC and TFC. However, the rate of efficiency increase in ORC is higher than the TFC, which can be clearly seen, especially at high maximal cycle temperatures. Using super dry working fluids, the recuperator‐free TFC has favorable cycle efficiency at high heat source temperatures. In contrast, by adding heat recovery for both systems, the ORC can outperform the TFC at 0.4, 0.2, and 0.1 recuperated heat effectiveness for Dodecane, Decane, and Nonane, respectively.
Thermal characteristics of Li‐ion battery based on phase change material‐aluminum plate‐fin composite heat dissipation
Authors: Liu Feifei , Gan Shulong , Chen Yangyang , Qin Wu , Li Jun 
Published: November 2022

AbstractA reliable battery thermal management system (BTMS) not only can effectively decrease the maximum temperature but also maintain the temperature uniformity of the lithium‐ion (Li‐ion) battery after grouping. Nevertheless, considering the deficiency of a single heat dissipation method, there exist challenges in efficient heat dissipation structure design, especially at high discharge rates. In this work, a composite heat dissipation structure of battery module with phase change material (PCM)–aluminum plate–fin is proposed. Meanwhile, the transient effects of different discharge rates, melting points, and thickness of PCM on the thermal characteristics of the module are analyzed. Results show that the maximum temperature of the module with PCM–aluminum plate–fin can be reduced by 25.8°C, 11.0°C, and 10.2°C respectively at 4 C discharge rate compared with natural convection, aluminum plate–fin, and paraffin PCM, and the maximum experimental error among them is less than 5%. During 2–5 C discharging, the melting rate of phase change increases first and then decreases, which leads to the trend of the maximum temperature and maximum temperature difference of the module rising with bending twice. When the ambient temperature is 25°C, the paraffin PCM with a melting point of 28°C is implemented for battery cooling because of its more rapid melting and heat absorption. The increase in PCM thickness is beneficial to the heat dissipation of the module. The optimal PCM thickness of 3 mm can realize temperature uniformity control within 2.5°C.
Numerical and experimental studies of packed bed thermal energy storage system based on a novel transient energy model
Authors: Ma Xiaoteng , Fan Chunchao , Shao Wei , Cao Qun , Cui Zheng 
Published: November 2022

AbstractPacked bed thermal energy storage (PBTES) is an essential means to solve the temporal difference and continuity between energy supply and utilization in the fields of concentrating solar power, compressed‐air energy storage, and waste heat recovery. In this paper, to solve the imperfection and inaccuracy of the current energy model, a precise transient two‐dimensional multiequation model is developed. The model comprehensively considers thermal dispersion, wall effects, thermophysical property changes, and other factors. Experiments are performed to compare and validate the simulation results, and the simulation error is −4.5% to 1.9%, achieving excellent simulation accuracy. Also, the wall effect on the PBTES is observed, and the gas‐solid temperature fields exhibit an evident nonuniform oscillation distribution in the radial direction. The effects of storage tank length, thermophysical properties, particle diameter, and gas‐solid initial temperature on the heat release rate are discussed in detail. Results indicated that decreasing the tank length, increasing the gas‐solid temperature difference, and particle materials with high thermal diffusivities can increase the heat release rate, and a clear linear change was found. Particularly because a larger range of particle diameter variation is considered, the heat release rate is shown to vary nonlinearly with particle diameter, and the selection of the optimal diameter must comprehensively consider the effects of the heat capacity and the heat transfer rate. This study provides a theoretical basis for the design of thermal energy storage systems.
Study on the energy capture efficiency of flapping airfoil power generator using semiactive dual‐layer airfoils
Authors: Xu Wu , Jianyang Zhu , Peng Xie 
Published: November 2022

AbstractTo address the problem that the energy capture efficiencies of existing flapping airfoil power generators are lower than those of traditional turbine generators, a dual‐layer flapping airfoil structure was adopted to improve the energy capture performance of the semiactive flapping airfoil, inspired by the multiwing flying mode of dragonflies in nature. The influence of the dual‐layer flapping airfoil structure on the energy capture performance of a semiactive flapping airfoil was systematically analyzed by a Taguchi experimental design and computational fluid dynamics simulations. The results showed that the dual‐layer flapping airfoil structure mainly improved the energy capture efficiency of the flapping airfoil by increasing the lift force and reducing the maximum sweep distance. Under the optimized parameter combination, the energy capture efficiency of the dual‐layer flapping airfoil reached 28.80%, which was 17.74% higher than that of the single‐layer flapping airfoil. Furthermore, the influence of the dual‐layer flapping airfoil structure on the energy capture performance of a semiactive flapping airfoil was related to the mass ratio of the system, and a larger mass ratio (M* ≥ 40) caused the performance of the dual‐layer flapping airfoil to deteriorate. Analysis of the vortices around the flapping airfoil revealed that there were more attached vortices on the surface of the dual‐layer flapping airfoil, but the increase in the mass ratio led to an advance of the separation of the leading edge vortex, which was the reason that the dual‐layer flapping airfoil with a smaller mass ratio had a better energy capture performance.
Study on rock mechanics characteristics of deep shale in Luzhou block and the influence on reservoir fracturing
Authors: Han Lingling , Li Xizhe , Liu Zhaoyi , Guo Wei , Cui Yue , Qian Chao , Huang Yize 
Published: November 2022

AbstractThis paper aims to study the influence of deep formation conditions on the mechanical properties of shale, which is of great significance for the engineering application of efficient development of deep shale gas. In this study, a real‐time high‐temperature (25°C–170°C) triaxial compression experiment was first carried out on shale samples. Then, based on the analysis results of rock mineral components and discrete element numerical simulation technology, a thermo‐mechanical coupling model (TMCM) was constructed, and the accuracy of the numerical model was verified. Finally, based on the micromechanical parameters, a numerical fracturing mechanism model considering the influence of temperature, natural fracture density, and fracture length was established, and the influence of current reservoir conditions on hydraulic fracturing was discussed. The results show that confining pressure has a greater effect on rock mechanics than temperature. When the temperature exceeds 110°C, the plasticity of rock samples increases, and the fracture morphology becomes complex. In addition, the increase in temperature promotes the fracture of microcracks to a certain extent. The research results are expected to provide a sufficient theoretical basis for the development and utilization of deep shale gas resources.
Planning of renewable and storage‐based standalone microgrid for reliable electrification
Authors: Asghar Ali , Kamal Md Mustafa , Ashraf Imtiaz 
Published: November 2022

AbstractWorld's large population lives in remote areas where electricity is unavailable or unreliable supply. For electricity supply, a low‐cost, minimum‐emission hybrid renewable energy system is necessary due to power shortages or unavailability, high electricity costs, and large greenhouse gas emissions. The current work develops a standalone hybrid power generating system and assesses its techno‐economic feasibility for rural sites in the Lucknow area of Northern India. To address the electric load requirement, the proposed work includes a system that includes a solar photovoltaic (SPV) module, a lead‐acid battery, a wind turbine (WT), and a diesel generator (DG). The system is sized and optimized using the hybrid optimization of multiple energy resources software. In this off‐grid system, the proposed system is intended for a home load need of 52.00 kWh/day with a peak of 11.04 kW. The technical and financial specifications are drawn from the local Indian market for the proposed standalone system. In this article, seven different resource combinations are investigated. A combination of 13 kW DG, 16 kW SPV, 50 kWh lead‐acid battery, 9 kW inverter, and 4 kW WT produces the best optimal system. With a 98.4% renewable portion, the cost of energy and total net present cost are $0.162/kWh and $57 390, respectively. The sensitivity analysis inflation and discount rates are 5.5% and 8%, respectively. As a consequence of the findings, we can conclude that the suggested standalone system is more cost‐effective for rural areas in Northern India.
Assessing the impact of enforcement and compliance with minimum staffing standards on the quality of care in nursing homes: Evidence from the Centers for Medicare and Medicaid Services' staff star rating downgrade policy
Authors: Brunt Christopher S. 
Published: November 2022

AbstractPolicymakers have historically attempted to influence quality in nursing homes through the imposition of minimum staffing standards and through the public dissemination of quality on websites like Care Compare. One current Federal standard necessitates a registered nurse (RN) on duty for at least eight consecutive hours each day. In 2018, the Centers for Medicare and Medicaid Services announced that they would incentivize compliance with this requirement by downgrading nursing homes with 7+ days without an RN present during the quarter by one star on their Care Compare staffing domain quality rating. This study evaluates the impact of this new enforcement mechanism. Using an intent‐to‐treat sample of nursing homes at risk for downgrade with difference‐in‐differences and event study models, it finds that the policy increased compliance and staffing levels. Using the policy to instrument for full compliance, it finds that the daily presence of an RN causally improves several quality dimensions.
Impact of long‐term care insurance on the health status of middle‐aged and older adults
Authors: Wang Jingyi , Guan Jing , Wang Guojun 
Published: November 2022

AbstractWith the increase of aging population, long‐term care insurance (LTCI) systems have become important for improving individuals' health. However, the effect of LTCI on health is unclear, especially in developing countries, owing to the lack of random policy shocks and comprehensive databases. This study investigates the Chinese LTCI pilot program, using four waves of the China Health and Retirement Longitudinal Study database (sample aged ≥45 years) from 2011 to 2018. The recent difference‐in‐differences approaches for staggered design, which are capable of dealing with the negative weights issue, are used to investigate changes in health status, measured by self‐rated health (SRH), (instrumental) activities of daily living, self‐rated depression, and cognition, in pilot and non‐pilot cities before and after LTCI implementation. Long‐term care insurance has a significant average effect on SRH improvement and a long‐term positive effect on cognition for middle‐aged and older populations. This study provides the first evaluation of LTCI policy on health outcomes using the recent difference‐in‐differences approaches. It provides evidence for the overall health improvement achieved through the LTCI and offers positive reinforcement and potential areas for improvement in establishing LTCI worldwide.
The influence of land management and seasonal changes in surface vegetation on flood mitigation in twoUKupland catchments
Authors: Bond Stephanie , Willis Thomas , Johnston Jean , Crowle Alistair , Klaar Megan J. , Kirkby Mike J. , Holden Joseph 
Published: November 2022

AbstractAs the frequency and magnitude of storm events increase with climate change, understanding how season and management influence flood peaks is essential. The influence of season and management of grasslands on flood peak timing and magnitude was modelled for Swindale and Calderdale, two catchments in northern England. Spatially‐Distributed TOPMODEL was used to investigate two scenarios across four storm events using empirically‐based soil and vegetation data. The first scenario applied seasonal changes in vegetative roughness, quantifying the effect on flood peaks at catchment scale. The second scenario modelled the influence of grassland management from historical high‐intensity grazing to a series of natural succession stages between grassland and woodland, and a conservation‐based management. Model outputs were analysed by flow type, measuring total, overland and base flow peaks at the catchment outlet. Seasonal changes to vegetation were found to increase overland flow peaks by up to +2.2% in winter and reduce them by −5.5% in summer compared to the annual average. Percentage changes in flood peak due to hillslope grassland management scenarios were more substantial; overland flow peaks were reduced by up to 41% in Calderdale where extensive woodland development was the most effective mitigation strategy, and up to 35% in Swindale, where a rank grassland dominated catchment was the most effective. Conservation‐based farming practices were also useful, reducing overland flow peak by up to 42% compared to the high intensity grazing scenario. Neither management nor seasonality changed the timing of runoff peaks by >45 min. Where overland flow dominates, especially in catchments with shallow soils, surface roughness was found to be more influential than soil permeability for flood mitigation. We recommend that seasonal changes to roughness are considered alongside the spatial distribution of Natural Flood Management in mosaiced upland catchments.
FinTechs and financial inclusion—Balkan experience: Digital perspectives on financial markets
Authors: Apostu Simona Andreea , Panait Mirela , Vasile Valentina , Sharma Gagan Deep , Vasile Razvan 
Published: November 2022

AbstractThe article aims to identify the stage of development of Fintech in the Balkan countries given the existence of numerous influencing factors Fintech is present in the Balkan countries, with a landscape colorfully generated by the different factors as the involvement of public authorities, the EU membership of only a few countries, the level of financial and digital education of the population. In order to highlight the variables influencing Fintech and financial inclusion in selected countries, specific indicators were used—internet usage and the share of bank assets in GDP, and several indicators regarding individuals performance, that is, online shopping, paid bills via internet, accessed a bank account online, paid utility bills using a mobile phone, made or received digital payments, account ownership and debit card ownership. The sample consists of all eight Balkan countries: Slovenia, Croatia, Bosnia and Herzegovina, Serbia, Montenegro, Albania, Macedonia, Bulgaria, and Romania. For testing the hypothesis in the analysis are used: descriptives, ANOVA, cluster analysis and principal components analysis. The results demonstrated that Balkan countries are not homogenous regarding Fintech and financial inclusion, the differences being generated both by the public policies in the financial field but also by IT development and by the population openness for using the new financial services and products. For these reasons, the authors identified economic policy measures that can be applied to increase financial inclusion in these countries given the facilities offered by Fintech and the digitization of financial products.
Prevalence and severity of discharge medication discrepancies resolved by pharmacists at a veterans affairs teaching hospital
Authors: Muller Alexander , Baric Jennifer E. , Kohmescher Diane , Kendall Ronald , Siler Andrew F. , Rusu Camelia , Evans Richard , Cotiguala Laura 
Published: November 2022

AbstractIntroductionAlthough reassuring outcome data exist, not all pharmacist discharge efforts have been effective. This may be explained by heterogenous medication reconciliation definitions and processes. At a Veterans Affairs Teaching Hospital, Clinical Pharmacy Specialists (CPS) review the discharge medication reconciliation as part of a multidisciplinary process. The objective of this study is to describe CPS' role in resolving discharge medication reconciliation discrepancies and to evaluate potential patient harm avoided through pharmacist intervention.MethodsPatients discharged home on at least one medication between October 21, 2021 and February 16, 2022 were included in this prospective single cohort study at a Veterans Affairs Hospital. Medication discrepancies were recorded. A panel of independent pharmacists categorized the clinical impact of discrepancies based on the potential to cause patient discomfort or clinical deterioration had the discrepancy gone unresolved: unlikely (class I), moderate (class II), or severe (class III).ResultsA total of 300 discharges were evaluated and 546 discrepancies identified. A majority (n = 202, 67.3%) of discharges had a discrepancy, with an average of 1.8 (SD ± 2.4) discrepancies per discharge. Pharmacists provided education during 84.3% of discharges and spent an average of 21.7 (SD ± 16.7) minutes per discharge. Panelists identified 359 (65.8%) class I, 149 (27.3%) class II, and 38 (7%) class III discrepancies. Omitted medication and incorrect dosing discrepancies conferred highest risk for potential patient harm. An increase in the number of medication changes from admission to discharge was the only variable predictive of discrepancies at discharge.ConclusionPharmacists play a vital role at hospital discharge by resolving discrepancies and mitigating potential adverse outcomes. Designing discharge systems that prevent omitted medication and incorrect dosing discrepancies may be beneficial as these errors had the largest potential clinical impact; however, this hypothesis was unable to be tested in this study and deserves further research.