Total Output Research Articles

Fatigue-induced alterations in force production, trajectory and performance in alpine skiing

ABSTRACT In giant slalom, the ability to apply a high amount of force in the radial direction is essential for performance. A race is characterized by repeated turns performed at high velocity, potentially inducing fatigue. Therefore, this study aimed to assess the effect of fatigue on performance, trajectory characteristics, and force production capacities onto the snow. Twelve skiers ran a 4-turn section with (FATIGUE) and without pre-induced fatigue (CONTROL). Knee extensor maximal voluntary contraction (MVC) was performed before the experiment and after both conditions. Section time, energy dissipation, path length, total force output, force application effectiveness, and EMG activity of the main lower-limb muscles were compared between conditions. Multiple linear regressions were used to understand whether interindividual variability in the kinematic, kinetic and EMG between conditions explains variability in performance changes with fatigue. MVC was lower after FATIGUE (−19.1 ± 6.4%, p < 0.001) but did not change after CONTROL. FATIGUE was associated with longer section times (+0.21 ± 0.11 s, p < 0.001), energy dissipation (−0.78 ± 1.05 J.s.kg.m−1, p = 0.026), path length (+1.1 ± 1.6 m, p = 0.033) and lower force application effectiveness (−0.1 ± 0.1, p = 0.017). This study experimentally demonstrates that fatigue in giant slalom results in lower force application effectiveness, inducing over-dissipation of mechanical energy and longer path length, leading to lower performance.

Diuretic therapy strategies in decompensated acute heart failure: a systematic review and network metanalysis

Abstract Background Congestion in acute heart failure (AHF) is treated with furosemide, mainly in continuous infusion (furosemide continuous, FC) or iv boluses, and combination of different diuretics. Randomized controlled trials (RCTs) only compared the efficacy and safety of some diuretic strategies with discordant results. Purpose To provide a comprehensive synthesis of the effects of diuretic regimens in AHF. Methods The PubMed, EMBASE, SCOPUS and Cochrane databases were searched for phase III RCTs until July 31st, 2023, evaluating diuretics without any other intervention in patients admitted for AHF, with randomization within 48 hours, no run-in period and/or need of clinical stabilization. The arms assigned to iv boluses or undefined schemas of furosemide/loop diuretic (LD) were grouped together as "furosemide bolus" (FB). The endpoints were weight loss over 24 hours (WL), worsening renal function (WRF), total urine output (tUO) and net urine output (nUO) over 24 hours, hypokalemia (hypoK), and hyponatremia (hypoNa). Heterogeneity was estimated by Thompsons’ I2 statistics, and odds ratios (OR) with 95% confidence intervals were calculated by means of a random-effects model with inverse variance weighting. A leave-one-out analysis, an analysis limited to studies with specified mode of furosemide/LD administration, and an analysis of measures of congestion/decongestion were also carried out. Results Twenty-five RCTs were selected, for a total of 7,095 patients with mean age 69.2±11.1 years and mean LVEF 38.1±12.7%. In subjects treated with furosemide/LD, the mean furosemide equivalent dose was 154.7±53.0 mg/24 hours. Heterogeneity was moderate-to-high (37.3%-66.0% across the study endpoints). FC, FB plus tolvaptan, FB plus sodium-glucose cotransporter inhibitor (SGLT2i), and FB plus thiazide were associated with greater WL than FB (Figure 1A). The combination of FB and thiazide or SGLT2i also portended higher odds of WRF than FB alone, as did the combination of FB and acetazolamide (Figure 1B). tUO was greater with FC (OR 2.77 [1.98-3.88]), FB plus tolvaptan (OR 1.69 [1.22-2.35]), and FB plus SGLT2i (OR 1.95 [1.16-3.28]) than with FB, and nUO was greater with FC (OR 1.50 [1.06-2.13]) and FB plus tolvaptan (OR 1.76 [1.06-2.92]) than with FB. Compared with FB, hypoK was more frequent with FB and thiazide (OR 1.68 [1.29-2.19]), while there was a trend for less hypoK events with FB plus tolvaptan (OR 0.86 [0.69-1.08]). No differences in hypoNa rates were found. Sensitivity analyses were consistent with the main one. Thirteen (52%) and 14 (56%) studies had published information about symptoms and signs of congestion, respectively, and 6 (24%) adopted pre-specified scoring systems. Conclusions FC and most combination diuretic regimens have greater efficacy than FB in promoting WL and diuresis, but at the cost of WRF and hyoK, especially when thiazide is used. Congestion has inconsistently been evaluated in RCTs of diuretic therapy in AHF.

Direct comparison of mechanical circulatory support devices in porcine model of acute myocardial infarction complicated by ventricular septal defect and cardiogenic shock

Abstract Introduction Despite urgent clinical need, until now optimal strategy for mechanical circulatory support in acute myocardial infarction (AMI) complicated by ventricular septal defect (VSD) and cardiogenic shock has not been determined. Purpose The aim of our study was to compare hemodynamic effects of intra-aortic balloon pump (IABP), extracorporeal membrane oxygenation (ECMO) and Impella CP in the animal model of AMI complicated by VSD and cardiogenic shock. Methods Under general anesthesia and mechanical ventilation in pigs (sus scrofa domestica), using partial sternotomy, AMI was induced by ligation of left anterior descending. VSD was simulated by insertion of 25F cannulas into the left and right ventricles and their extracorporeal connection by 3/8 tubes generating left-to-right shunt. The hemodynamic effect of ECMO (2 L/min), IABP, and Impella CP (2 L/min) was evaluated by the measurement of the left ventricular end-diastolic pressure (LVEDP), mean arterial pressure (MAP), carotid flow (CAR) as a surrogate of total circulatory output, and VSD flow. Data are presented as mean (SD), P &amp;lt; 0.05 was considered statistically significant. Results Eleven animals were used, one died after induction of AMI, ten pigs completed all study procedures. Baseline (no mechanical support) LVEDP was 13.8 (3.0) mmHg, MAP 54.5 (11.0) mmHg, CAR 290.9 (37.3) mL/min, and VSD 1174.0 (499.3) mL/min (Table 1). IABP significantly improved all parameters in comparison to Baseline (Table 1). ECMO significantly improved MAP and CAR not only in comparison to Baseline but also in comparison to IABP and Impella; on the other hand, ECMO increased VSD flow (Table 1). Impella significantly improved all parameters with the largest effect on LVEDP and VSD flow (Table 1). Conclusions All tested devices improved the key hemodynamic parameters of MAP and CAR, however each to different extent. Individual devices influenced differently LVEDP and VSD flow. The results of this study may help in selection of optimal therapeutic strategy in AMI complicated by VSD and cardiogenic shock.Table 1.Hemodynamic outcomes.

Fulfilling the potentials of residential solar energy in Egypt

Energy plays a very important role in Egypt’s economic development, but the country has a gap between its produced energy and the demand of its growing population. Utilization of solar power systems in Egypt could help the country to close this gap and fulfil its national and international obligations. However, since 1980, the focus in Egypt has been on large-scale industrial solar projects. Limited attention is given to smaller systems for typical residential buildings. The aim of this research, therefore, is to highlight the potential of small residential solar systems (SRSS) in Egypt. With the huge number of residential buildings accommodating more than 115 million Egyptians, SRSS could be the unearthed gem of a sustainable source of energy in Egypt. The geographical location of Egypt and climate were used to generate solar data using the Global Solar Atlas application. The amounts of monthly and annual solar irradiations were calculated and analysed to decide the best orientation of the system (facing east, west, north, and south), identify the optimum tilt angle of the system, and determine the size of the solar panels. A case study was used to illustrate the procedures of designing SRSS for a typical residential building in Egypt. The results showed that a 26 kWp SRSS oriented facing the east with an optimum tilt angle between 15° and 30° could produce an annual total output of electricity more than the annual demand of the occupants of the studied residential building. Such a system would fit easily on the roof of the building. It was concluded that the installation of SRSS in Egypt could help the country meet the demand of its ever-increasing population if properly regulated, financed, and managed. It is recommended that Egypt develop and implement policies to make installations of SRSS an attractive choice among homeowners and investors by introducing encouraging incentives and creating a competitive market with affordable SRSS.

Achieving Flat Ultra‐Broadband NIR Emission in Cr3+ Doped Garnet‐Type Phosphors Enabled by Structural Regulation Toward Multi‐Functional Spectroscopy Applications

AbstractCr3+‐activated near‐infrared (NIR) emitting phosphors are considered as one of the most potential light‐conversion materials for NIR phosphor converted light‐emitting diodes (NIR pc‐LEDs). However, it is still a challenge for a single Cr3+ ion to achieve a flat ultra‐broadband emission toward multi‐functional spectroscopy applications. Herein, a chemical unit co‐substituting strategy is utilized to regulate the crystallographic occupancy of Cr3+ ions, and a flat ultra‐broadband NIR emission is successfully realized with a record emission wavelength of 915 nm in garnet‐type phosphors Ca3Sc2‐xHfxAlxSi3‐xO12: yCr3+ (0 ≤ x ≤ 1, 0.02 ≤ y ≤ 0.06), together with a large full width at half maximum (FWHM) regulation from 130 to 250 nm. The relation between the site occupation of Cr3+ ions in disordered [CaO8], [(Sc, Hf)O6] and [(Si, Al)O4] polyhedrons and the corresponding NIR emission are clarified by carefully evaluating the structural evolution, Raman spectra, electron paramagnetic resonance and time‐resolved emission lifetime spectra of Cr3+ ions. The corresponding crystal field strength of Cr3+ ions is investigated to further clarify the multi‐sites induced flat broadband NIR emission. Finally, a blue light pumped NIR pc‐LED is fabricated with a total output power of 37.58 mW and photoelectric conversion efficiency (PCE) of 13.67%@100 mA, which realizes the multi‐functional applications in night vision imaging, non‐destructive detection and palmprint vein recognition for assistant medical treatment.

Impacts on Regional Growth and “Resource Curse” of China’s Energy Consumption “Dual Control” Policy

Accurately evaluating the effectiveness of the energy consumption “dual control” policy can effectively solve serious the current environmental pollution and promote ecological civilization. However, researchers have rarely considered the impacts on the regional “resource curse” of the energy consumption “dual control” policy. A dynamic computable general equilibrium model (CGE) was built to evaluate the impacts on the regional “resource curse” of the energy intensity control and total energy control policy. The results showed the following. (1) The energy consumption “dual control” policy changes the supply-and-demand relationship of factors and reduces the crowding-out effect of humans and capital. (2) The energy consumption “dual control” policy has restrained GDP growth, and the total output and total investment have declined. However, the impact in regions without the “resource curse” is remarkable. (3) The energy consumption “dual control” policy has a significant inhibitory effect on major pollutants and carbon emissions. (4) The energy consumption “dual control” policy has played a positive role in breaking the regional “resource curse”. The areas with a high and low “resource curse” have become smaller, and the areas without the “resource curse” have increased significantly. The following suggestions are made: (1) increase the flexibility of the “dual control” policy of energy consumption, (2) establish an energy consumption budget management system, and (3) accelerate the establishment of a carbon footprint management system.

The efficacy of crossbreeding on reproductive and productive performance in New Zealand White and Flemish Giant rabbits

Crossbreeding is a well-established practice in livestock production aimed at improving reproductive and productive traits. This study evaluated the effects of crossbreeding on rabbits, focusing on comparisons between purebred Flemish Giant (n = 10), New Zealand White (n = 23), and their crossbred offspring (n = 27). Various parameters, including litter size, body weight, growth rate, and mortality, were assessed. The results demonstrated that crossbred rabbits presented a 15% faster growth rate than purebred rabbits, along with the lowest mortality rate and highest total meat output. This phenomenon, attributed to hybrid vigour, effectively blends the large frame of the Flemish Giant with the good litter size of the New Zealand White. Furthermore, statistical analyses, including ANOVA and Tukey‒Kramer’s honestly significant test, confirmed the significant effects of breed class on productivity, body weight, and carcass yield. Growth curves estimated using the Gompertz model highlighted the superior performance of crossbred rabbits under semiarid conditions. Notably, crossbreeding resulted in offspring with the highest dressing percentage and overall improved performance, offering potential advantages for rabbit producers worldwide.

Understanding and estimating the role of large-scale seaweed cultivation for carbon sequestration on a global scale over the past two decades

Seaweeds, as marine photosynthetic organisms, are harvested by humans from the wild or through cultivation for various production purposes and to provide a range of marine ecosystem services, including nutrient removal, oxygen production, and carbon sequestration. The potential use of cultivated seaweed in mitigating carbon dioxide (CO2) has been extensively proposed in conjunction with commercial seaweed production worldwide. This study aims to assess the annual potential and benefits of cultivated seaweed in reducing and fixing anthropogenic CO2. Over the past two decades (2000–2019), global seaweed production has seen significant growth. The total output of cultivated seaweed reached 407.4 × 107 tons (t), with coastal mariculture removing 4.26 × 107 t of carbon annually and wild capture removing 2.24 × 106 t. The recalcitrant dissolved organic carbon (RDOC, 549.88–621.60 × 104 t) plays a significant role in the carbon sinks of seaweed cultivation. The substantial benefits of carbon sink resulting from the formation of RDOC from seaweed make up a considerable proportion in the calculation of carbon sequestration and sink enhancement benefits in large-scale seaweed cultivation. The sizable carbon sink base of seaweed cultivation (8631.90–9567.37 × 104 t) results in significant carbon fixation benefits. The total economic value of carbon sequestration and oxygen production was estimated at $70.36 ± 1.52 billion, with an annual average benefit of $3.52 ± 1.70 billion. Increasing the area and yield available for cultivated seaweed has the potential to enhance biomass production, carbon accumulation, and CO2 drawdown. It is crucial to emphasize the need for improved communication regarding the essential criteria for the feasibility of CO2 removal (CDR), with a focus on conducting life cycle assessments (LCA) when utilizing marine processes in the present and future work. The sustainable development of the seaweed cultivation industry not only ensures that Asian-Pacific countries remain leaders in this field but also provides an effective yet overlooked solution to excessive CO2 emissions worldwide.

The Potential Bioactive Components in Fruits Wastes as Value-Added Products from the Fruit Processing Industry: A Review

Fruits are an important source of nutrition as most of them contain sufficient amounts of minerals, vitamins, and antioxidants. However, processing these fruits results in enormous waste, accounting for around 40% of total food output. Fruit processing industry waste includes discarded pods, peels, pulp, stones, and seeds all of which can pose environmental and sustainability challenges. Importance of discovering the potential of fruit processing waste into value added products lies in the fact that the fruit processing industries generates substantial waste, contributing to environmental pollution, greenhouse gas emissions, and resource depletion. The solid waste generated by the fruit processing industry may include toxic biological components that contaminate aqueous media, degrade drinking water quality, and cause gastrointestinal disorders in animals. However, Fruit processing waste or byproducts have the potential to be converted into value-added goods of economic importance like candied peel, oils, pectin, reformed fruit fragments, enzymes, and wine/vinegar candied peel. Converting this waste into valuable products can mitigate these issues, while also creating new revenue streams, jobs, and industries. Furthermore, value-added products from fruit processing waste can enhance food security, nutrition, and sustainability, supporting the United Nations' Sustainable Development Goals (SDGs). Additionally, research in this area can also lead to technological innovations, improved efficiency and scalability, enabling companies to gain a competitive edge in the growing market for sustainable products. This article provides an overview of all common and possible consumer friendly uses of fruit processing wastes and deriving value added products out of it.

Emergy-Based Evaluation of the Sustainability of Agricultural Ecosystem in Dazhou, China, from 2002 to 2022

Our aim is to analyze the emergy evaluation indicators of the agricultural ecosystem in Dazhou, northeastern Sichuan, and provide practical and effective recommendations for sustainable agricultural development. Using emergy analysis, the emergy inputs and outputs of an agricultural ecosystem from 2002 to 2022 were calculated. Five emergy indicators were selected for evaluation: emergy yield ratio (EYR), emergy self-sufficiency ratio (ESR), emergy input ratio (EIR), environmental load ratio (ELR), and emergy sustainable indices (ESI). The total emergy input of the agricultural ecosystem showed an upward trend from 2002 to 2017, thus the industrial auxiliary emergy input decreased, somewhat curbing its continued rise from 2017 to 2022. The structure of emergy inputs, in descending order, is as follows: industrial auxiliary &gt; organic emergy &gt; renewable environmental resources &gt; non-renewable environmental resources. The total emergy output of the agricultural ecosystem was highest in 2007, reaching 2.31 × 1022 Sej, and lowest in 2012, at 1.83 × 1022 Sej. The structure of emergy outputs, in descending order, is as follows: livestock &gt; planting &gt; fishery &gt; forestry. The emergy yield ratio fluctuated down from 3.12 to 2.51, with an average of 2.88, below the provincial average of 3.07. The emergy self-sufficiency ratio fluctuated down from 0.30 to 0.26, with an average of 0.27, above the provincial average of 0.13. The emergy input ratio fluctuated up from 2.31 to 2.91, with an average of 2.66, above the provincial average of 1.86. The environmental load ratio fluctuated from 3.8 to 4.75, with an average of 4.40, which is higher than the provincial average of 1.68. The emergy sustainable indices fluctuated down from 0.81 to 0.53, with an average of 0.67, below the provincial average of 1.17. The efficiency of resource utilization in the agricultural ecosystem of Dazhou has decreased, economic inputs have increased, and it is in a consumptive production process. The pressure on the local natural environment is increasing, and the capacity for sustainable development remains at a low level over the long term.

Forecasting Wholesale Electricity Market Prices Considering Bidding Conditions Using Price Sensitivity

This article proposes a sophisticated forecasting model to predict significant price volatility on the Japan Electric Power Exchange (JEPX) due to the growing influence of solar photovoltaics (PV) in the energy mix. As solar power generation continues to grow, it significantly impacts the daily and seasonal price trends in the market. This method employs a neural network that integrates daily prices, net electricity demand (total demand minus PV output), and underlying time‐series data to determine the objective variable, defined as the deviation from the average price over the past week. Incorporating price sensitivity data from JEPX increases the accuracy of the model. These data reflect how prices respond to market‐specified bid adjustments, including a variety of bidding, providing a nuanced understanding of market responses. The results demonstrate that adding multiple price sensitivities significantly improves the model's ability to detect price spikes and provides a robust tool for transmission and distribution system operators to manage risk and optimize their market strategies in an increasingly renewable energy‐dominated landscape. This approach not only addresses daily and seasonal price fluctuations but also aligns with broader sustainability goals as the share of solar PV generation continues to grow.

Enhanced composite controller for PV/PMSG/PEMFC and BESS‐based DC microgrids voltage regulation: Integrating integral terminal sliding mode controller and recursive backstepping controller

AbstractThe variability of renewable energy sources due to weather patterns often leads to a mismatch between power generation and consumption within microgrids (MGs). This challenge is exacerbated when integrating bio‐renewable units, complicating stability maintenance in MGs. This research work introduces a novel solution to address this issue: a composite controller merging an integral terminal sliding mode controller with a recursive backstepping controller for direct current MGs (DCMGs). The proposed DCMG incorporates solar photovoltaic units, wind farms based on permanent magnet synchronous generators, proton exchange membrane fuel cells fuelled by hydrogen gas, an electrolyser, battery energy storage systems, and DC loads. First, a comprehensive mathematical model for the components within the DCMG is developed to design the proposed composite controller. This controller not only overcomes the inherent limitations and convergence issues of conventional SMCs but also ensures stable DC‐bus voltage and maintains power balance across various operational conditions. Moreover, a fuzzy logic‐based energy management system is introduced to regulate power flow, considering factors like battery state of charge and renewable energy sources' total power output. The control Lyapunov function confirms the DCMG system's asymptotic stability. Finally, the proposed controller's effectiveness is validated through simulations on both MATLAB/Simulink and Arduino Mega 2650 processor‐in‐the‐loop platforms under various operational conditions. In both platforms, the proposed controller surpasses an existing controller in terms of settling time, overshoot, and tracking error of the DC‐bus voltage.

A Novel Hydrogen Production System Based On Multistage Reverse Electrodialysis

Salinity gradient energy can be converted into hydrogen energy through the system combining multi-stage reverse electrodialysis (MSRED) with polymer electrolyte membrane water electrolysis. However, the relevant performance of the system has never been investigated. In this paper, the influence of relevant parameters of MSRED on the performance of the system was analyzed theoretically through a reliable mathematical model. The results showed that increasing the flow velocity of solutions will cause remarkable decrease in the energy recovery of the system, although the total output power and hydrogen production rate of the system increase correspondingly. Besides, thickening compartments of the high concentration solution is effective to reduce the energy consumption for pump with a small augment in the total output power and hydrogen production rate of the system, while the energy recovery of the system is still dropping slowly.

Publishers and production of academic books in Mexico: 2013-2019.

Background: The project Cartograf&amp;iacute;a de la Edici&amp;oacute;n Acad&amp;eacute;mica Iberoamericana aims to analyze the production of academic books in Spanish- and Portuguese-speaking countries in the Americas. Following the path opened by similar studies in Colombia and Brazil, we present the results for Mexico. Objectives: To analyze academic books published in Mexico between 2013 and 2019 to examine the entities that published the books and their respective shares in the total output. Methods: A mix of quantitative and qualitative approaches was used to characterize the Mexican publishers of academic books based on data on ISBNs, the International Standard Book Numbers. The data comprised the information provided to the agency that assigns a unique ISBN to each book. We also used the Delphi method and formed discussion groups of experts. The groups were set up on the basis of responses to semi-structured questionnaires that sought to determine the criteria an entity must satisfy to be considered an academic publisher. Conclusions: Of the 196 533 ISBNs issued in Mexico between 2013 and 2019, 117 929 (60%) were issued for books dealing with academic subjects. Commercial publishers accounted for the largest share of those books (63 044 ISBNs, or 53.4% of all the academic books), followed by university presses (29 628 ISBNs, or 25.1%). The group of experts suggested that among the 1289 publishers that requested ISBNs for academic books, only 151 (11.7%) can be considered truly academic publishers; 678 (52.6%) cannot; and 460 (35.7%) were borderline cases, as they meet some but not all the criteria for them to be considered truly academic.

CiteSpace-based Survey of International Advances in Chinese Traditional Culture Research in 1999-2019

With the globalization strategy and the initiative “One Belt and One Road” in China, Chinese traditional culture has a great impact on the world. This study, based on CiteSpace, explores the total numbers, hotspots, characteristics and tendency of international research on Chinese traditional culture, by retrieving 866 articles from SSCI and A&amp;HCI in the Web of Science (Core Collection). The results of the study revealed that: there is a strong increases in total output from 1999 to 2019 and the research on the theme of Chinese traditional culture has become interdisciplinary; the most productive authors aren’t the ones in the most cited documents and the journals on which the most cited documents publish aren’t the prolific journals; most of the researchers are from Hong Kong, Taiwan, mainland of China, Canada and USA. In view of the results, it is obvious that it is a good way to spread Chinese traditional culture over the world. It is strongly recommended that we should do more analysis on the international literatures with different paradigms, methods and metrics in order to get a more comprehensive and correct domain visualization map of Chinese traditional culture research.

The prospect of floating photovoltaic in clean energy provision and net-zero-emissions

AbstractThis study emphasizes the critical role of renewable energy in addressing climate change challenges, particularly in reducing greenhouse gas emissions. It highlights the central importance of solar photovoltaic systems. While recognizing South Africa’s progress in renewable energy deployment, the study notes that substantial efforts are still needed to meet the country’s renewable energy targets. The study’s primary aim is to enhance the understanding and deployment of solar photovoltaic systems by critically examining the photovoltaic potential and performance of different sites. To achieve this, two scenarios—land photovoltaic and floating photovoltaic systems—were considered, focusing on hypothetical 10 MWp-installed capacity systems. The results indicate that the 10-MWp land photovoltaic system has a global tilted irradiance of 2184.7 kWh/m2, an annual total output of 18 GWh, and an average yearly performance ratio of 81%. The economic parameters for the land photovoltaic system include a capital expenditure of $9.0 million, an operational expenditure of $157,500 annually, and a levelised cost of energy of $0.04089/kWh. In contrast, the 10-MWp floating photovoltaic system reports a Global Tilted Irradiance of 1797 kWh/m2, an annual total output of 16 GWh, and a performance ratio of 76%. The economic parameters for the floating photovoltaic system include a capital expenditure of $10.6 million, an operational expenditure of $176,250 annually, and a levelised cost of energy of $0.04936/kWh. Both scenarios’ econo-technical parameters fall within acceptable ranges. However, the land photovoltaic system shows better performance, indicating some efficiency loss in the floating photovoltaic system possibly due to harsher offshore conditions. Based on the data from the reports, the study concludes that the econo-technical feasibility of floating photovoltaic in the Western Cape Province of South Africa is high. Graphical abstract

A 90SrHfO3-based betavoltaic/beta-photovoltaic dual-effect integrated nuclear battery

In this paper, the secondary conversion idea is used to reduce the self-absorption effect of the radioactive source by combining the radioactive source with the scintillation material, so as to enhance the energy conversion efficiency of the battery. A theoretical model of a dual-effect integrated nuclear battery based on 90SrHfO3 doped with Ce is proposed. The emission photon and electron spectra of the β-luminescent integrated radioactive source 90SrHfO3 have been calculated by GEANT4. The average outgoing electron energy of SrHfO3 was calculated, and the thickness of the energy reducing material was determined. The effect of structural parameters of GaAs materials on the dual-effect integrated nuclear battery was analyzed to obtain the optimal output performance according to theoretical calculation. From the perspective of conversion efficiency, the activity density and thickness of 90SrHfO3 are determined to be 1.6 Ci/cm2 and 53.6 μm. At this time, the thickness of SrHfO3 is 1.28 mm. The total maximum output power density of the optimized dual-effect integrated nuclear battery is 9.31 μ W/cm2, and the energy conversion efficiency is 0.18 %. At this point, the doping concentrations of GaAs are Na = 1.26 × 1017 cm−3 and Nd = 6.31 × 1018 cm−3, and xj is 0.05 μm. Compared with nonintegrated batteries, the output performance is significantly improved.

Power allocation optimization strategy for multiple virtual power plants with diversified distributed flexibility resources

AbstractThe virtual power plant integrating the flexible resources in the distribution network can provide additional adjustment capacity for the auxiliary services of distribution network. However, the actual internal situation of distribution network including insufficient adjustable capacity of energy storage, unreasonable power allocation, and voltage overrun leads to the difficulties in optimization scheduling. Therefore, this paper proposes a power allocation optimization strategy of distributed electricity‐H2 virtual power plants (EHVPPs) with aggregated flexible resources. Specifically, a distributed EHVPP division method based on the granular K‐medoids clustering algorithm is proposed to realize the independent autonomy and coordinated interaction between EHVPPs, and in order to quantify the operation and regulation capacity of distributed EHVPPs, an aggregation approach of regulating feasible domains of flexibility resources based on the improved zonotope approximations is developed. Moreover, a power allocation strategy based on the flexibility weight factor is proposed to handle the calculated minimum deviation between the total active output of PV and the dispatching power command, realizing the self‐consistency of distributed EHVPPs. Comparative studies have demonstrated the superior performance of the proposed methodology in economic merits and self‐consistency efficiency.

Research on short-term optimization and scheduling of multi-energy complementary systems based on forecast scenario dynamic correction

The inherent unpredictability and instability of renewable energy sources, such as wind and solar power, hinder the precise execution of power generation plans in complementary systems, posing significant challenges to their integration into power grids. Therefore, this study proposes a dynamic correction method for wind and solar output forecast scenarios in the short-term scheduling of wind-solar-hydro complementary systems. The method utilizes statistical analysis of forecast errors in wind and solar power outputs to characterize uncertainty patterns across different forecast levels and constructs a typical forecast scenario set based on single-day forecasts. This approach probabilistically models each scenario according to the temporal migration patterns of wind and solar power outputs and develops a neural network-based dynamic correction fusion model to refine the forecasts. Application of this method in a case study of the Yalong River Basin demonstrated that, after applying dynamic correction to the forecast scenarios, the mean absolute error in total wind and solar output predictions during the wet and dry seasons was reduced by 50.73 % and 47.95 %, respectively. Additionally, the dynamic correction reduced the maximum residual load on typical wet and dry days by 82.70 % and 62.37 %, respectively, and decreased the total intraday residual electricity by 91.17 % and 73.24 %, compared to single-day forecasts. The study concludes that the proposed dynamic correction method enhances power system stability and improves power generation efficiency and reliability.

Performance analysis of triple basin solar still with energy-exergy analysis approach

An experimental investigation was conducted on novel design of triple basin solar still with different modification in the climatic conditions of India. The triple basin solar still was modified with attachments of evacuated tubes (ETCs), heat pipes (HP), corrugated surfaces and energy storage materials called modified triple basin solar still (MTBSS). To get the more water in distillate output and higher water temperature solar still was designed with three basin area. From experimental results it was found that the total distillate output obtained by MTBSS during day and night was 16.46 l/m2 and 7.40 l/m2, respectively. The performance of MTBSS was also check by 4E (Energy, Exergy, Exergo-Economic, Exergo-Environmental) analysis for economical and environmental point of view. The generation of exergy for evaporation (Exe,bw-ig) and convection (Exc,bw-ig) for MTBSS (Modified triple basin solar still) were 24.03 &amp; 1.30 (joule) respectively. The values of energy efficiency (ƞenergy) and exergy efficiency (ƞexergy) obtained for MTBSS were 31.89% &amp; 3.04% respectively. An economic point of view, the CPL of water remains higher in MTBSS. The NPBT for MTBSS was 2.5 months. For environmental assessment, the CO2 mitigation for MTBSS was 0.48 t/year, based on the exergy approach. The additions of ETCs, H.P, corrugated surface, and ESMs with MTBSS are effective from an exergo-economic and carbon credit point of view.