Search Results (479)

Background: Twin-screw wet granulation (TSWG) is a promising continuous manufacturing technology, featuring high operational flexibility, short residence time and consistent quality. The process development of TSWG relies on the synergy of material characterization, screw configuration, and process parameter optimization. Objective: In order to fully combine various design variables, and to accelerate the process development of TSWG, a material–process–equipment integrated design (MPEID) methodology is first applied to the TSWG process of Guizhi Fuling capsule, a botanical drug product. Methods: First, an equivalent formulation was designed to save trial costs. Second, 3D printing technology was used to customize both conveying and kneading elements with the lead, with the kneading discs stagger angle (SA) and the thickness (thick) as screw element variables. The position of fabricated kneading elements was varied to generate different screw configurations. Then, the critical screw parameters (CSPs) and critical process parameters (CPPs) were identified by a two-step design of experiment (DOE) toward optimizing granule quality. Results: As a result, the SA and thick were identified as CSPs, and the liquid-to-solid ratio was the CPP. Under the optimal TSWG process conditions, the twin-screw granulator could be operated under low torque (i.e., average torque = 1.48 ± 0.06 Nm). The dried granules exhibited superior flowability, as well as highly consistent particle size distribution with industrial batches. After capsule filling, the dissolution test results showed the prepared Guizhi Fuling capsules reached 93.7% cumulative dissolution at 15 min, which approached that of commercial capsules (i.e., 93.0%). Conclusions: This study demonstrated the feasibility of proposed MPEID methodology, supporting the efficient and cost-effective process development of TSWG. Full article

With the increasing integration of grid-friendly concentrated solar power (CSP) plants into high-proportion new energy power systems, the system is confronted with challenges such as insufficient regulation capability and power balance difficulties. To address these issues, this paper proposes a multi-stage optimal regulation strategy for CSP–wind power systems based on adaptive step-size model predictive control (ASMPC), from the perspectives of tapping transmission line current-carrying capacity and coordinating system regulation resources. This strategy first establishes an electro–thermal–mechanical coupling dynamic line rating (DLR) model to characterize line safety margins, then constructs an optimization decision-making model aiming at minimizing the total multi-stage coordinated scheduling cost and adopts ASMPC to dynamically adjust the control step size, effectively improving scheduling accuracy and real-time correction capability. Simulation results based on the modified IEEE 39-bus system show that the proposed method reduces the total system cost by 26.8% (nearly 30%), increases the CSP unit output ratio by 27.9%, and decreases the average grid load rate by 12.6 percentage points. The proposed strategy can effectively mitigate the impact of source-load uncertain fluctuations and significantly improve the economic operation level of the CSP–wind power combined system. Full article

In the context of the energy transition and increasing environmental pressures, firms’ competitiveness increasingly depends on effective energy–cost management and environmental performance. However, integrating energy, financial, and environmental dimensions into performance evaluation remains methodologically challenging. This study develops an exergy-based two-stage Network Data Envelopment Analysis (NDEA) framework linking energy and cost management in Stage 1 to financial performance under environmental constraints in Stage 2. Using Refinitiv/London Stock Exchange Group (LSEG) data for 45 firms across 18 industries in Portugal and Spain in 2023, the model integrates thermodynamic, financial, and environmental indicators within a unified efficiency framework. The Exergy-to-Sales ratio serves as a fixed intermediate link between thermodynamic and financial efficiency. Results show that incorporating environmental performance increases the number of fully efficient firms in overall efficiency from 3 to 5, while 27 firms move closer to the efficiency frontier. The environmental specification reduces the average improvement required for Return on Sales (ROS) and Return on Equity (ROE) but increases the adjustment needed for Return on Assets (ROA), indicating heterogeneous profitability responses. The study contributes to sustainable performance assessment literature by integrating exergy analysis and NDEA within a unified decision-support framework for managers and policymakers pursuing competitiveness and decarbonization objectives. Full article

Objectives: Treadmill walking is often employed for tightly controlled gait and energetics research, but growing evidence suggests that treadmill-based metabolic and biomechanical measurements may not directly reflect the ecologically valid mode of overground walking. While many previous studies focused on older adults, much less is known about how treadmill walking influences gait energetics and spatiotemporal parameters in young healthy adults across matched speeds. We investigated energy expenditure, metabolic cost of walking and spatiotemporal gait parameters in healthy young adults walking overground and on a treadmill at three speeds (slow—1.0, comfortable—1.3, fast—1.5 m/s). Our hypothesis was that at the comfortable speed, treadmill and overground energetics and gait parameters would be comparable. However, at slow and fast speeds, there would be a significant energetic penalty, accompanied by significant differences in spatiotemporal parameters. Methods: Twenty young participants (10 males and 10 females) completed a randomized cross-over walking protocol with a minimum of ten minutes treadmill familiarization at 1.3 m/s. Breath-by-breath oxygen consumption ($\dot{V}{O}_2$) and Respiratory Exchange Ratio were measured using a portable indirect calorimetry system and gait parameters were calculated from Inertial Measurement Units. Gross and net energy expenditures, costs of walking, cadence, average step and stride lengths, and walk ratio were calculated. A three-way mixed ANOVA was used for primary statistical analyses. Results: Treadmill walking was characterized by higher gross and net energy expenditures and metabolic costs (p < 0.001, η_p² = 0.6) across all speeds compared to overground. It was also characterized by faster cadence and shorter average step and stride lengths (p < 0.001, η_p² = 0.9). Additionally, there was an effect of sex (p = 0.01, η_p² = 0.3) on the gait parameters, with females exhibiting a faster cadence and shorter average step and stride lengths than males. Conclusions: Our findings show that treadmill walking imposes a medium-to-large metabolic penalty even in healthy young adults, with compensatory gait adaptations, possibly reflecting increased stabilization demands and altered neuromuscular control strategies. These results underscore the limits of generalizing treadmill derived gait data to overground walking and we caution against the uncritical use of treadmills, especially while trying to understand ecologically relevant human walking mechanics and energetics. Full article

The safe and stable operation of air-insulated switchgear (AIS) in high-altitude and low-pressure environments is significantly affected by partial discharge (PD), which accelerates insulation aging and may threaten power system reliability. Therefore, effective online monitoring and fault diagnosis methods are of considerable engineering importance. This paper proposes a PD-type recognition method based on the concentration ratio of two characteristic decomposition gases, CO and NO₂. First, a hybrid numerical model coupling fluid dynamics and plasma chemistry was established to simulate the microscopic decomposition mechanism of air discharge. The simulation results indicate that CO and NO₂ are relatively stable and detectable among the considered air-discharge products and that their generation is promoted by increased average electron energy under low-pressure conditions. Subsequently, an experimental platform was developed to simulate three typical insulation defects, namely point discharge, air-gap discharge, and surface discharge, under different simulated altitudes. Quantitative analysis using Fourier-transform infrared spectroscopy and gas chromatography revealed clear correlations between defect type and gas concentration characteristics. Based on these results, a diagnostic criterion was established under the tested conditions: a CO/NO₂ concentration ratio less than 1 indicates the epoxy-resin-based surface discharge model, whereas a ratio greater than 1 indicates point discharge or air-gap discharge. The latter two types can be further distinguished according to the time-dependent increasing trend of the ratio for air-gap discharge. Finally, based on the observed diffusion characteristics of these gases in the laboratory switchgear model, a low-cost online detection prototype using semiconductor gas sensors was developed. Laboratory validation using three typical single-defect models showed that the proposed method achieved 100% recognition accuracy when sufficient time-series data were available. However, further field validation is required before large-scale industrial application. The proposed CO/NO₂ ratio method provides a potential low-cost auxiliary diagnostic approach for AIS insulation monitoring, particularly under high-altitude and low-pressure conditions. Full article

Reluctance Magnetic Gears (RMGs) represent a cost-effective alternative to conventional magnetic gears, replacing the inner rotor permanent magnets with a toothed ferromagnetic rotor and adopting rectangular instead of arc-shaped magnets on the outer rotor. While these design choices reduce manufacturing complexity and material costs, they inherently introduce higher torque ripple, making simultaneous optimization of average torque and ripple a critical and non-trivial task. In this work, a multi-objective genetic algorithm is applied to four RMG configurations with integer gear ratios GR_int equal to 4, 5, 6, and 7, with a fixed inner rotor tooth number n₃ equal to 5. Seven design variables are optimized simultaneously: five radial thicknesses and two fill factors. The resulting Pareto fronts quantify the trade-off between average torque and ripple for each configuration. Analysis of the optimal solutions reveals a consistent geometric allocation pattern across all gear ratios, suggesting the existence of a common optimization criterion potentially generalizable to other RMG configurations. The influence of the gear ratio on both torque performance and optimal parameter distribution is discussed in detail. Full article

Background: Intraocular surgery on patients with an irreversibly blind fellow eye carries high risks, often causing treatment delays due to patient and surgeon hesitation. Existing data beyond cataracts are scarce. This study aims to evaluate the clinical profiles, prognosis, and economic value of diverse surgeries in this monocular population to guide clinical decision-making and optimize blindness prevention strategies. Methods: This retrospective study included 308 patients with a pre-existing blind fellow eye who underwent primary inpatient intraocular surgery under a standardized clinical protocol between June 2021 and June 2025. Baseline demographics, bilateral etiologies, visual outcomes, postoperative complications, and average cost-effectiveness ratios (ACERs) were analyzed. Postoperative outcomes were evaluated for patients with at least 6 months of follow-up. Results: The primary surgical indications were cataract (51.3%), proliferative diabetic retinopathy (PDR, 19.5%), glaucoma (15.9%), and rhegmatogenous retinal detachment (RRD, 7.5%). Notably, 49.4% of patients exhibited identical blinding etiologies bilaterally. Among patients completing the 6-month follow-up (n = 109), overall mean BCVA significantly improved from 1.36 ± 0.77 to 0.73 ± 0.65 logMAR (p < 0.001). The cataract group achieved the greatest visual improvement and the lowest ACER. Despite surgical complexity and higher complication rates, PDR and RRD interventions achieved visual improvement in over 60% of cases. Conclusions: Despite high clinical stakes, timely surgery in monocular patients yields substantial visual and economic benefits. The notable disease symmetry highlights a critical window for early intervention, emphasizing the need for public health strategies that prioritize screening progressive bilateral diseases. Full article

N-carbamylglutamate (NCG) is a structural analog of N-acetylglutamate and has multifunctional roles in animal production. However, few studies have been conducted to evaluate the effects of NCG on protein digestive function and muscle growth in broiler chickens. This study investigated whether NCG could improve muscle growth via protein digestive ability and amino acid metabolism in broiler chickens. A total of 144 one-day-old male broiler chickens were randomly allocated to four treatments with six replicates of 6 broiler chickens each. The treatments were a basal diet and a basal diet with NCG supplementation at three graded levels (150 g/t, 300 g/t, and 450 g/t of NCG). The results showed that NCG supplementation significantly improved the average daily weight gain (ADG) and decreased the feed conversion ratio (FCR) compared to the control group (p < 0.05) and increased the weight of leg muscle and breast muscle. Furthermore, NCG supplementation significantly increased protein digestibility, the activities of amylase, trypsin and lipase, and villus height in the ileum (p < 0.05), which demonstrated that digestibility and absorption were improved by NCG in broiler chickens. Analysis of plasma amino acids, hormone levels and the gene expression of breast muscle revealed that NCG increased the concentration of GABA, glutamate, glutamine, leucine, threonine, valine, branched-chain amino acids and essential amino acids and the levels of testosterone and IGF-1 in plasma (p < 0.05). Additionally, NCG increased the expression of mTOR and P70S6K in breast muscle tissue. Therefore, NCG supplementation could be an important nutritional strategy to improve product performance, muscle growth and development, and meat yield. The 300 g/t supplementation level was found to be the practical optimum dose, as it produced effects comparable to the highest dose (450 g/t) on most parameters while offering better cost-effectiveness. This study provides new insights into the application of NCG for meat production improvement in broiler chickens. Full article

Background: The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) has increased rapidly in pediatric populations. Evidence on the cost-effectiveness of pediatric MASLD screening strategies remains limited. Methods: A decision tree combined with a Markov state-transition model was developed to evaluate the cost-effectiveness of three WHtR-based two-stage screening strategies among children aged 6–14 years in Beijing, China: WHtR combined with ultrasound (S1), WHtR combined with FibroScan^® (S2), and WHtR combined with magnetic resonance imaging-proton density fat fraction (MRI-PDFF) (S3), compared with no screening (S4). All screening strategies were combined with lifestyle modification programs, including dietary and exercise management. Model inputs were derived from the published literature, national survey data, and expert consensus. Costs and quality-adjusted life years (QALYs) were estimated from a healthcare system perspective over a 10-year time horizon, with a 3% annual discount rate. Incremental cost–utility ratios (ICURs) were calculated, and extensive one-way, two-way, and probabilistic sensitivity analyses were performed. Results: Our model indicated that, at a willingness-to-pay (WTP) threshold of $30,584.0 per QALY, corresponding to three times the gross domestic product (GDP) per capita of China, S2 was identified as the optimal strategy. At a higher WTP threshold of $71,415.5 per QALY, based on the GDP per capita of Beijing, S3 became the most cost-effective option. All three screening strategies were more cost-effective than no screening across both thresholds. Sensitivity analyses demonstrated that utility values for fibrosis stages and the response rate of the lifestyle modification program were the most influential parameters, and probabilistic sensitivity analysis confirmed the robustness of the baseline findings. Conclusions: To the best of our knowledge, this is the first cost-effectiveness analysis for pediatric MASLD in China. Model-based estimates suggest that early screening for MASLD in children using WHtR-based screening strategies is cost-effective, with FibroScan^® preferred in settings with average economic development and MRI-PDFF preferred in more affluent regions. These findings underscore the importance of context-specific implementation of early MASLD screening strategies in pediatric populations to mitigate long-term disease burden. Full article

The purpose of the article is to present the influences and their weights on the price formation of agricultural and food products in Slovenia. The influences are defined by the ratios of input and output prices and quantities of raw materials, semi-finished products, and products within the food systems of individual stakeholders in the theoretical design of price difference construction, the definition of individual stakeholders’ costs, and the assessment of the dynamics of price and quantity fluctuations from the annual average. The analysis is based on the specified econometric model bases on the Ridge formulation, which represent an analytical model of the price formation in the agri-food chains in Slovenia. The results determine and explain the weight of the impacts based on composite independent variables (based on the calculation of the relationships between individual variables with respect to the mutual responsiveness of changes–elasticity of behaviour) which were defined using available data collected in accordance with the Law on Agriculture in the Republic of Slovenia. Several new independent variables were developed to explain the effects of the independent variable representing the difference in the price of agricultural and food product between the beginning and the end in the analyzed food supply chain. The discussion connects practical actions that address three important future development components of agriculture: strengthening accessibility, competitiveness, and the stability of the position of Slovenian agriculture within the EU. Full article

The accurate and efficient acquisition of rock mechanical properties is critical for ensuring the safety and efficiency of underground engineering construction. Traditional laboratory tests are characterized by long cycles, high costs, and an inability to reflect in situ mechanical properties, while existing deep learning models based on while-drilling data suffer from poor noise robustness, insufficient deep feature extraction, and low accuracy in synchronous multi-parameter prediction. To address these limitations, this paper proposes a hybrid deep learning model (CNN-LSTM-MoE) combining a convolutional neural network (CNN), a long short-term memory network (LSTM), and a mixture of experts (MoE) system. The model enables intelligent prediction of elastic modulus, Poisson’s ratio, and yield stress from while-drilling parameters. The proposed model integrates CNN’s local feature extraction capability, LSTM’s temporal dependency modeling capability, and the multi-expert dynamic fusion mechanism of MoE. Furthermore, it incorporates physical constraints from rock fragmentation mechanics and an adaptive multi-objective loss weight optimization strategy to comprehensively enhance the multi-parameter synchronous prediction performance. Experimental results demonstrate that the proposed model achieves coefficients of determination (R²) of 0.8965 for elastic modulus, 0.9193 for Poisson’s ratio, and 0.9813 for yield stress on the laboratory validation dataset, with a mean squared error (mse) of 4.0720. Its prediction performance significantly outperforms benchmark models such as TCN and Transformer time-series architectures. Ablation studies further validate the critical role of the integrated LSTM and MoE modules in improving model accuracy, with the MoE module contributing an average R² improvement of approximately 24%. This study not only provides an effective method for high-precision acquisition of rock mechanical parameters while drilling, but also offers a feasible solution based on numerical simulation for data augmentation to address the common issue of scarce labeled data in deep learning applications within engineering fields. Full article

During the worldwide energy transition, wind power has become a leading development direction. Compared to large-scale horizontal-axis wind turbines (HAWTs), small-scale vertical-axis wind turbines (VAWTs) show potential, lack yaw mechanisms, adapt to wind direction changes, and are cost-effective. However, small-scale VAWTs operate in the near-surface atmospheric boundary layer and are sensitive to low-temperature and high-humidity climates, which cause blade icing. Ice buildup leads to fluctuations in aerodynamic loads, reduces power output, and diminishes stability. This study focuses on the NACA-0018 airfoil, using a low-temperature wind tunnel platform to simulate freezing durations to obtain ice characteristics on the blade surface. Based on ice profiles, numerical models were developed. Computational fluid dynamics (CFD) techniques were used to perform unsteady simulations of aerodynamic performance at various icing durations, investigating the influence on the power coefficient. The results indicate that the effect of icing duration on the average power coefficient depends on TSR. At the 5 min icing stage, the optimal tip-speed ratio decreases. Icing deteriorates aerodynamic performance at high tip-speed ratios, while producing positive optimization effects at low tip-speed ratios. This paper reveals the variation patterns of aerodynamic performance and differentiated mechanisms during the icing process of small vertical-axis wind turbine blades, providing a theoretical basis and data support for the development of surface anti-icing technologies and safe, efficient operation in low-temperature environments. Full article

The increasing integration of distributed photovoltaic (PV) systems in urban environments requires planning frameworks that simultaneously address economic viability, environmental sustainability, and power system performance. This study develops a simulation-based techno-economic and environmental assessment framework for evaluating hybrid rooftop photovoltaic (PV) and building-integrated photovoltaic (BIPV) deployment under harsh climatic conditions. Detailed system modelling using PVsyst and ETAP is conducted to analyse energy production, economic performance, environmental impact, and grid interaction characteristics, including voltage deviation and harmonic distortion. To support deployment planning and operational decision-making, the simulation outputs are incorporated into a multi-objective optimisation framework that evaluates trade-offs among levelized cost of energy (LCOE), net present value (NPV), carbon emission reduction, and power quality indicators. Three deployment configurations including rooftop PV only, BIPV only, and a hybrid PV–BIPV system are assessed using structured trade-off analysis and Pareto optimality principles. Results indicate that the hybrid configuration provides the most balanced performance across technical, economic, and environmental objectives. The system achieves an average performance ratio of 77.36% and generates approximately 2075 MWh of annual energy while maintaining grid voltages within acceptable limits and harmonic distortion well below IEEE 519 thresholds. Economic analysis shows strong financial feasibility with an LCOE of approximately 0.05 USD/kWh, a payback period of 8.1 years, a net present value of about 2.88 million USD, and a return on investment exceeding 145%. Loss analysis further identifies temperature effects and dust accumulation as the dominant performance constraints under harsh environmental conditions. Moreover, Pareto-based evaluation confirms the hybrid PV–BIPV configuration as the preferred deployment strategy among the evaluated alternatives. The proposed framework demonstrates how integrated simulation and multi-objective optimization can serve as a practical decision-support tool for planners and policymakers seeking to optimise distributed renewable energy deployment under climatic and operational uncertainties. Full article

The objective of this paper is to offer a mathematical formulation of economic value added (EVA) that incorporates distance-to-default (DD) and thus a default-free capital structure. The latter is extended via the weighted average cost of capital (WACC) to introduce a default-free EVA. The data include the nonfinancial firms listed in the DJIA30 and NASDAQ100 covering the period 1992Q2–2023Q3. The results of standard specification tests and the GMM estimator show that (a) DD causes an increase in WACC and thus, EVA decreases; (b) the interest coverage ratio can be used effectively to compensate for default risk, thus adjusting the default-free EVA positively; (c) both EVA and default-free EVA can effectively be managed via common determinants, namely, net working capital ratio, total liabilities to EBITDA, sales growth rate, debt–equity ratio, and earnings per share; (d) the positive impact of the inflation rate on both EVA and default-free EVA justifies the use of default-free EVA as a metric for equity risk premium; and (e) the robustness of the results via stochastic geometric Brownian motion shows that the determinants of default-free EVA are stable. This paper contributes to related studies by incorporating credit risk via the DD into default-free EVA. Full article

Provider payment reform is widely regarded as an important policy instrument for improving medical service efficiency, while empirical evidence on mixed provider payment systems remains limited. Taking China’s Sanming healthcare reform as a case, this study examines the effects of a mixed provider payment system that combines global budgets with diagnosis-related group (DRG)-based payment, referred to as the “double-bundling” reform, on medical service performance. Using a balanced panel dataset of public medical institutions in Sanming from 2014 to 2023, we exploit the staggered rollout of the reform as a quasi-natural experiment and estimate its effects using a staggered difference-in-differences approach. The results show that the reform significantly reduced the inpatient-to-outpatient admission ratio while increasing average length of stay and bed occupancy rate. These findings suggest that the reform was associated with higher admission thresholds, fewer potentially avoidable hospitalizations, and improved bed utilization within county-level medical institutions. Additional results indicate that the reform contributed to outpatient cost containment without a statistically significant increase in the average cost per inpatient admission. Overall, the evidence suggests that the provider payment reform helped strengthen cost-control incentives and improve the alignment between expenditure restraint and service delivery efficiency within vertically integrated county-level medical alliances. This study provides empirical evidence from China for the design of mixed provider payment reforms in integrated delivery systems. Full article