Efficiency Improvement Research Articles

Does an environmental stringent policy really matter to achieve environmental sustainability in BRICS-T region? Evidence from novel method of moments quantile regression approach

Amidst pressing global environmental challenges, exacerbated by climate change and the imminent threat of global warming, there is a critical need to assess the efficacy of environmental policies. This study centers its attention on the pivotal role of these policies in addressing environmental concerns. Specifically, our research aims to scrutinize the impact of stringent environmental policies on environmental quality under the theoretical underpinnings of environmental Kuznets curve. To achieve this objective, the study collected data from BRICS-T economies over the period of 1990–2020. This study employed the method of moments quantile regression technique for empirical analysis. Our study validates the presence of the Environmental Kuznets curve (EKC hypothesis). Empirical findings reveal the sustained significance of environmental stringency across all quantiles, demonstrating a positive correlation in lower quantiles and a negative correlation in higher quantiles. At lower quantiles, the impact is insignificant initially, but pronounced due to efficiency improvements induced by stringent policies. The effects became negative at middle quantiles, indicating stringent policies might encounter diminishing returns where policy measures start stabilizing ecological impacts. At higher quantiles, the influence of ESI remains significant, reflecting ongoing adaptations in larger economies with higher ecological footprints. This suggests the potential effectiveness of stringent regulatory measures in mitigating environmental impacts and reducing ecological footprints. The identified inverted U-shaped curve signifies that while stringent policies may not inherently enhance environmental health, beyond a certain threshold, they can indeed contribute to its improvement. Our policy recommendation advocates for the widespread adoption and promotion of such stringent measures to safeguard environmental health.

Integrating Dynamic Time Warping and K-means clustering for enhanced cardiovascular fitness assessment

The appropriate measurement of cardiovascular ’Performance Enhancement’ is critical for improving physical fitness and overall health. Traditional methods, effective as they are, often rely on complex, cumbersome equipment, limiting their practical use for real-time, dynamic exercise evaluation. Thus, understanding the intricate relationship between physiological responses and exercise ‘Performance Enhancement’ using wearable technology is essential for tailoring effective fitness regimes. This study involved 52 participants, utilizing Garmin Vivosmart 5 wearables to analyze heart rate time series during the YMCA Three-Minute Step Test, assessing fitness levels and characterizing personalized heartbeat dynamics. The study employed Dynamic Time Warping (DTW) for clustering these time series into high and low VO2max groups. Additionally, heart rate dynamics were examined using K-means clustering to identify distinct patterns during exercise—namely ‘Efficient Adaptation’, ‘Balance Under Pressure’, ‘Active Strain’, and ‘Efficiency Improvement’ clusters. This analysis demonstrated that non-trained individuals showed higher ‘Active Strain’ and ‘Efficiency Improvement’ dynamics and lower ‘Efficient Adaptation’ dynamics, indicating the exercise’s varied effectiveness based on training level. This method provides a novel approach for identifying individual fitness levels and the efficacy of specific exercises, enabling personalized physical activity planning.

Adaptation planning of container ports in the context of typhoon risks: The case of Ningbo-Zhoushan port in China

This study conducts a comprehensive survey of the risk of typhoon to container ports by assessing the risk level of typhoons in China's major container ports, predicting their economic losses, and evaluating corresponding adaptation measures. It analyzes adaptation measures in response to typhoon impacts, with a case study of Ningbo-Zhoushan port, one of China's most representative regional ports. It identifies the inadequate supply of institutions and the absence and misbehavior of the main port stakeholders as the main cause of varying institutional imperfections in the port adaptation system. This study contributes to the development of efficient port typhoon prevention policies, reduction of economic losses and casualties, and improvement of port operational efficiency. It also fills an important research gap on climate risk and adaptation in China's container ports, with an emphasis in enhancing port resilience.

Synergistic Modulation of π-π* and n-π* Transitions by In Situ Phenol-Like Structure Integration for Efficiently Wide-Spectrum Hydrogen Production of Ultrathin Carbon Nitride.

2D carbon nitride nanosheets, exemplified by g-C3N4, offers significant structural benefits and enhanced photocatalytic activity. Nonetheless, the quantum confinement effect prevalent in nanoscale photocatalysts would result in an enlarged bandgap, potentially restricting the spectral absorption range and impeding improvements in photocatalytic efficiency. Here, a high-performance 2D photocatalyst with an extended spectral response is achieved by incorporating a novel phenol-like structure into the conjugated framework of ultrathin g-C3N4 nanosheet. This novel strategy features targeted pyrimidine doping to create a conjugated carbon zone in heptazine structure, offering a thermodynamically favorable pathway for hydroxyl functionalization during the annealing exfoliation process. Consequently, the π-π* transition energy in the material is significantly decreased, and the active lone pair electrons in phenol-like structure induces a new n-π* transition with notably enhanced absorption from 500 to 650nm. The optimized material shows a dramatic enhancement in photocatalytic activity, achieving ≈72 times than the activity of bulk g-C3N4, and demonstrating a measurable H2 production rate of 6.57µmol g-1 h-1 under 650nm light. This study represents a significant step forward in the strategic design of 2D photocatalysts, with tailored electronic structures that significantly boost light absorption and photocatalytic efficiency.

Thermodynamic modeling and analysis of a Carnot battery system integrating calcium looping thermochemical energy storage with coal-fired power plant

Long-term energy storage and carbon capture technologies are pivotal in managing renewable energy surpluses and achieving carbon neutrality. This paper proposes a Carnot battery system integrating calcium-looping thermochemical energy storage with a coal-fired power plant. The system utilizes excess electricity from the grid for energy input, facilitating long-term energy storage, achieving carbon capture, and reducing coal consumption in the power plant. An optimization framework is developed, incorporating component thermodynamic models and optimization algorithms, to maximize the coal savings in plants and energy efficiencies of the Carnot battery system. During the energy release process, the carbonator partially replaces the reheat load of the boiler, necessitating retrofitting of the boiler’s heating surface to ensure normal operation. The base system demonstrates a CO2 capture capacity of 3.23 MJ/kg and a reduction in coal consumption by 7.07 %. The round-trip efficiency and comprehensive efficiency of the base system are 36.93 % and 37.91 %, respectively. The relatively low energy efficiency is primarily due to the deactivation of circulating adsorbents and the limited efficiency of the subcritical coal-fired power plant. By incorporating an additional recarbonation step to mitigate adsorbent deactivation, the system’s comprehensive efficiency is improved to 42.20 %. Further improvements in system efficiency can be achieved by using modified adsorbents with high cycling stability instead of natural limestone and by coupling the system with more efficient ultra-supercritical units instead of the investigated subcritical units. This study offers valuable insights into the development of long-term energy storage solutions and multifunctional Carnot battery technology.

Using a metasurface to enhance the radiation efficiency of subterahertz antennas printed on thick substrates

This study investigates the possibility of increasing the radiation efficiency of printed antennas and arrays by suppressing their inherent surface waves using a metasurface made of quad-split rings (QSR). A symmetrical resonant microstrip dipole and a four-element series-fed dipole array printed on an infinite grounded dielectric layer (layer thickness: 0.2 mm; relative permittivity: 9.4; tanδ: 0.0005) were simulated with FEKO 2022 software. Conducted at 100–116 GHz, the numerical results revealed extremely low radiation efficiencies of approximately 31% and 40% for the studied dipole and dipole array, respectively, which resulted from the presence of surface waves in the dielectric. However, placing only one QSR near each dipole arm triggered an increase in radiation efficiency by 2.5 times (up to 75%). The use of a metasurface in the form of two small QSR arrays triggered a pronounced improvement in radiation efficiency, reaching 93.6% and 95.8% for the studied dipole and dipole array, respectively. Analysis of the electric field distribution images showed that this enhancement resulted from surface wave suppression.

Enhanced thermal shock resistance and higher molten steel purification efficiency of Al2O3-MgAl2O4-C filter with in-situ β-SiC whiskers: Compared with Al2O3-C filter

The porous ceramic filter is mainly utilized in the final stage of molten steel casting and serves as an important means for adsorbing non-metallic inclusions in order to improve the quality of the steel. In this study, Al2O3-MgAl2O4-C filter (filter AM) was prepared from porous Al2O3-MgAl2O4 micropowder, and referenced Al2O3-C filter (filter A) was prepared from α-Al2O3 micropowder. The phase composition, microstructure, mechanical properties and purification efficiency on molten steel of filter AM were compared with filter A by XRD, SEM, EDS and immersion test with molten steel. The results indicate that the filter AM exhibited a uniform skeleton without cracks, and plenty of β-SiC whiskers were generated internally. However, there were some cracks in the strut of filter A with the formation of many SiC/SiO2 spheres inside. The different microstructures resulted in the retention rate of cold compressive strength after thermal shock test as high as 91.11 % for filter AM and only 58.06 % for filter A, respectively. According to the immersion test, an Al2O3-MgAl2O4 layer was formed on the rougher surface of filter AM and contributed to the adsorption of the inclusions, leading to about 80 % reduction in the quantity of inclusions of various sizes. The cleanliness of steel was significantly improved as the T.O content was reduced from 56.3 ppm to 11.7 ppm. Finally, the mechanisms underlying the enhancement of thermal shock resistance and the improvement of purification efficiency by porous Al2O3-MgAl2O4 micropowder were proposed.

Risk Prevention and Countermeasure Analysis in Enterprise Capital Operation

Under the premise of the continuous development of the economic market, enterprises must constantly expand their business scope and scale if they want to establish a foothold in the market competition, because the enterprise promotes the efficient operation of capital through the use of capital operation, laying the foundation for the improvement of enterprise efficiency. In the capital operation, because of the influence of internal and external environment, the risks faced by the capital operation of enterprises also increase, so it is very necessary to study how to prevent the risks of the capital operation of enterprises and countermeasures. Based on the relevant laws of the development of the market economy, this paper carries out a multi-angle analysis, and puts forward countermeasures to prevent the risks of enterprise capital operation, aiming at promoting the efficient and benign development of enterprise capital operation and making enterprises take the road of sustainable development.

MAN Network Optimization Through EIGRP Dynamic Routing and DUAL Algorithm: A Study Using Cisco Packet Tracer

This research examines the optimization of the Metropolitan Area Network (MAN) through the implementation of the Enhanced Interior Gateway Routing Protocol (EIGRP) and the Diffusing Update Algorithm (DUAL) using the Cisco Packet Tracer. The main goal is to improve the efficiency of routing and data management in MAN networks. This study involves designing a network topology with three routers, setting appropriate IP configurations, and implementing EIGRP and the DUAL algorithm. The results show significant improvements in routing efficiency and data management, confirming the importance of selecting appropriate routing protocols and network configurations for MAN network optimization. These findings contribute to network optimization practices, providing important insights for the development of more efficient urban communications infrastructure.

A CONTABILIDADE DIGITAL COMO FERRAMENTA DE GESTÃO APLICADA NA MICROEMPRESA X

Digital accounting is the modernization of accounting processes through information technology. It involves the use of specialized software to automate accounting tasks, such as issuing invoices, calculating taxes, and preparing financial reports. This makes it easier to access real-time information, increases data accuracy, and reduces operational time and costs. In addition, digital accounting allows for more efficient integration with other business systems, promoting a more agile and strategic financial management. Its general objective is to implement digital accounting tools in Microenterprise X, to meet this objective, we outline the following specific objectives: To analyze the existence of a digital information system in Microenterprise X in Manicoré; implement digital information systems in Microenterprise X in Manicoré and train employees to use the digital system implemented. As for the methodological procedures, the study had a qualitative-quantitative approach, through a questionnaire applied to the employees of Microenterprise X in this municipality. And as a result, we interpreted and analyzed each of the questions. Therefore, it is concluded that the implementation of digital accounting in micro-enterprises has a significant impact in several areas, promoting substantial improvements in operational efficiency, decision-making, compliance and security.

Multi-Objective Constrained Optimization Model and Molten Iron Allocation Application Based on Hybrid Archimedes Optimization Algorithm

The challenge of distributing molten iron involves the optimal allocation of blast furnace output to various steelmaking furnaces, considering the blast furnace’s production capacity and the steelmaking converter’s consumption capacity. The primary objective is to prioritize the distribution from the blast furnace to achieve a balance between iron and steel production while ensuring that the volume of hot metal within the system remains within a safe range. To address this, a constrained multi-objective nonlinear programming model is abstracted. A linear weighting method combines multiple objectives into a single objective function, while the Lagrange multiplier method addresses constraints. The proposed hybrid Archimedes optimization algorithm effectively solves this problem, demonstrating significant improvements in time efficiency and precision compared to existing methods.

Significant improvement of n-contact performance and wall plug efficiency of AlGaN-based deep ultraviolet light-emitting diodes by atomic layer etching

The reactive ion etching (RIE) process is needed to fabricate deep ultraviolet (DUV) light-emitting diodes (LEDs). However, the n-contact performance deteriorates when the high-Al n-AlGaN surface undergoes RIE, leading to decreased LED performance. In this study, we employed an atomic layer etching (ALE) technology to eliminate surface damage generated during the mesa etching process, thus enhancing the n-Al0.65Ga0.35N ohmic contact. The improved contact performance reduced LED operation voltage and mitigated device heat generation. It was observed that DUV LEDs treated with 200 cycles of ALE showed a reduction in operating voltage from 8.3 to 5.2 V at 10 mA, with a knee voltage of 4.95 V. The peak wall plug efficiency (WPE) was approximately 1.74 times that of reference devices. The x-ray photoelectron spectroscopy (XPS) analysis revealed that ALE removed the surface damage layer induced by plasma etching, eliminating surface nitrogen vacancies and increasing surface electron concentration. Consequently, it facilitated better ohmic contact formation on n-Al0.65Ga0.35N. This study demonstrates that the ALE technology achieves etching with minor surface damage and is suitable for use in III-nitride materials and devices to remove surface defects and contaminations, leading to improved device performance.

Effectiveness of early rehabilitation interventions in patients with traumatic brain injury using a large database.

Rehabilitation is important for patients with moderate-to-severe traumatic brain injury (TBI). However, the timing of early rehabilitation initiation is ambiguous, and its safety and effectiveness are unknown. To examine the effectiveness and safety of early rehabilitation in patients with moderate-to-severe TBI using propensity score analysis and a large database. Retrospective cohort study. A large medical database (JMDC database) of tertiary care facilities was used to compare outcomes of early and delayed rehabilitation. Patients aged between 20 and 90 years who were diagnosed with TBI were admitted to acute care hospitals. Inclusion criteria were patients undergoing rehabilitation within 7 days of admission with a Glasgow Coma Scale score of 3 to 12 on admission. This study included 3074 patients with moderate-to-severe TBI. Patients were classified into an early rehabilitation group (within 2 days of admission) or a delayed rehabilitation group (3 to 7 days postadmission), depending on when rehabilitation started after TBI. Rehabilitation was defined as any type or intensity of intervention provided by a physical, occupational, and/or speech/language therapist. Interventions were not controlled. The primary outcome was Barthel Index (BI) efficiency (BI gain/length of stay). Secondary outcomes included BI gain (discharge BI - admission BI), incidence of aspiration pneumonia complications during hospitalization, discharge to home, mortality, and length of stay. After applying inverse probability weighting with propensity scores, the total was 6152 patients. 3074 (50.0%) patients received early rehabilitation. The early rehabilitation group showed no difference in inpatient mortality (p = .438), improved BI efficiency (β = 0.86, p < .001), and shorter length of stay (β = -5.00, p = .018). Early rehabilitation in patients with moderate-to-severe TBI is associated with more efficient functional improvement and reduced hospital stays without an increase in inpatient mortality.

Achieving economy‐wide gains from residential energy efficiency improvements: The importance of timing and funding approach in driving the transition

AbstractResidential energy efficiency improvements are generally considered integral to achieving climate change targets. Alongside the primary benefits of reducing energy use and consumer bills, there is increasing policy interest in the potential for energy efficiency programmes to deliver economy‐wide gains, measured by gross domestic product, employment, household real incomes and spending power etc. Our previous research shows that such sustained gains are likely over time. Here, we consider how transitory outcomes are likely to be heavily influenced by the timing of actions and who pays, how and when. Insight in this regard is crucial for policy makers considering the mix and timing of measures to reach net zero outcomes that are economically as well as technically feasible. We consider alternative funding, distributions and timeframes for residential retrofitting costs and projects using a UK economy‐wide scenario simulation model. The key insight is that while government support for the provision of low‐cost finance options is strategically important in alleviating budget constraints and mitigating potential short‐term negative impacts on household spending, producer responses to the wind down of retrofitting spending can disrupt the adjustment of the economy. Here we identify pros and cons of different trajectories of action towards high‐level energy efficiency policy targets.

Understanding users of online energy efficiency counseling: comparison to representative samples in Norway

IntroductionTo achieve substantial energy efficiency improvements in the privately owned building stock, it is important to communicate with potential renovators at the right point in time and provide them with targeted information to strengthen their renovation ambitions. The European Union recommends using one-stop-shops (OSSs), which provide information and support throughout the whole process, from planning to acquisition of funding, implementation, and evaluation as a measure to remove unnecessary barriers.MethodsFor this paper, we invited visitors of two Norwegian websites with OSS characteristics to answer an online survey about their renovation plans and energy efficiency ambitions. The participants visited the websites out of their own interest; no recruitment for the websites was conducted as part of the study (N = 437). They also rated a range of psychological drivers, facilitators, and barriers to including energy upgrades in a renovation project. Their answers were then compared to existing data from representative samples of Norwegian households regarding home renovation in 2014, 2018, and 2023, as well as data from a sample of people who were engaged in renovation projects in 2014, which was collected by the research team with a similar online survey. Furthermore, 78 visitors completed a brief follow-up online survey one year later to report the implemented measures.ResultsWe found that visitors of the websites are involved in more comprehensive renovation projects and have substantially higher ambitions for the upgrade of energy efficiency compared to the representative samples. They also perceive stronger personal and social norms, as well as have a different profile of facilitators and barriers.DiscussionThe findings suggest to policymakers that OSSs should be marketed especially to people motivated to upgrade energy efficiency but lack information and are unable to implement their plans alone. Also, the construction industry might refer interested people to such low-threshold online solutions to assist informed and more ambitious decisions.

Selection of disassembly schemes for multiple types of waste mobile phones based on knowledge reuse and disassembly line balancing

The growing number of waste mobile phones (WMPs) have made recycling an urgent issue. Different disassembly schemes demonstrate varying effectiveness in the large-scale disassembly of WMPs. It is necessary to consider both economic benefits and efficiency improvement comprehensively. This paper applies knowledge reuse and disassembly line balancing to the automated disassembly of multiple types of WMPs. In this regard, descriptive standards for mobile phone disassembly knowledge at different workstations are established based on the theory of knowledge reuse. In light of mobile phone disassembly characteristics, workstation thresholds, threshold intervals, and excessively small thresholds are introduced to improve the selection of disassembly line schemes. Based on a quantitative analysis of disassembly line balancing, the selection schemes for disassembling different batches of phones have been optimized. Case studies are conducted on Android and iOS system smartphones to verify the proposed method. The experimental results demonstrate that our proposed method, which incorporates disassembly knowledge, judgment thresholds, and selection schemes, substantially enhances the accuracy of disassembly line selection. For iOS system phones, designing two lines can disassemble all models of WMPs. For Android system phones, the retirement time of mobile phones influences the selection of lines in the disassembly process. Phones with earlier retirement times are more likely to be selected for simpler disassembly lines. Based on disassembly line balancing, two proposed cases for disassembling different batches of phones increase the overall disassembly efficiency by 48.4 % and 46.7 %, respectively.

Sustainable potato farming in Shandong Province, China: a comprehensive analysis of organic fertilizer applications

IntroductionThe potato holds the distinction of being the world’s largest non-cereal food crop and ensuring its sustainable production is imperative for global food security. Notably, China leads in both the planting area and output of potatoes globally, cementing its crucial role in the nation’s agricultural economy. A scientific assessment of the effectiveness of organic fertilizers on potato cultivation can significantly contribute to the promotion of sustainable agriculture.MethodsThis study utilizes a Propensity Score Matching (PSM) model and introduces a novel cost-efficiency approach to analyze and evaluate the production efficiency and economic impact of organic fertilizer application among 546 potato growers in Shandong.ResultsThe research findings reveal the following: Firstly, compared to the control group without organic fertilizer application, it is evident that the use of organic fertilizers enhances production technology efficiency, labor productivity, land productivity, and net profit per unit by 3.6%, 1588.47 kg/person, 16346.77 kg/ha, and 16135.32 yuan/ha, respectively. Secondly, an examination of cost efficiency among growers with different production scales indicates that those with a planting scale of 0.667-1.333 hectares demonstrate relatively high production efficiency across multiple factors. Additionally, there is an observable inverted U-shaped trend in the relationship between planting scale and production efficiency. Thirdly, the continuous application of organic fertilizers proves advantageous in mitigating inefficiencies in investment techniques, leading to cost savings and efficiency improvements in potato cultivation.DiscussionConsequently, it is recommended that the government and relevant departments enhance technical support, elevate professional training programs, and optimize the allocation of input factors. These measures aim to encourage farmers to adopt organic fertilizers, thereby promoting sustainable agricultural practices.

Multichannel seismic attenuation compensation and interpolation with curvelet sparse constraint of frequency-wavenumber spectrum

Abstract High-resolution exploration is hampered by seismic attenuation, caused by the viscosity and heterogeneity of underground media. Conventional single-channel attenuation compensation methods can increase the corresponding vertical resolution partially. While the lateral continuity of compensated seismic data is always ignored and the noise resistance can be improved. Therefore, multichannel attenuation compensation methods were proposed, including the algorithm with sparse curvelet coefficient constraint of the time-space (t-x) data. However, nonstationary seismic data may be affected by irregular missing traces in field cases, which severely degrades its lateral continuity and negatively affects the performance of multichannel attenuation compensation. Therefore, we concentrate on simultaneous multichannel attenuation compensation and missing trace interpolation in a unified framework. Based on the inversion framework of sparsity promotion, we propose an approach for simultaneous multichannel compensation and interpolation, utilizing sparse curvelet coefficient constraint of the recovered principal frequency-wavenumber (f-k) spectrum. The size of the principal f-k spectrum is reduced by at least half compared with that of the corresponding t-x band-limited data. It significantly reduces the computational expense of curvelet transform-based processing. Synthetic and field data experiments validate the effectiveness of the proposed method in efficiency improvement with consistent performance when compared to the multichannel method with sparse curvelet coefficient constraint of the t-x data in improving the vertical resolution and lateral continuity. Furthermore, we have discussed a potential acceleration strategy based on random sampling in the normal compensation issue.

Size-Controllable and Monodispersed Lipid Nanoparticle Production with High mRNA Delivery Efficiency Using 3D-Printed Ring Micromixers.

Lipid nanoparticles (LNPs) are gaining recognition as potentially effective carriers for delivery of therapeutic agents, including nucleic acids (DNA and RNA), for the prevention and treatment of various diseases. Much effort has been devoted to the implementation of microfluidic techniques for the production of monodisperse and stable LNPs and the improvement of encapsulation efficiency. Here, we developed three-dimensional (3D)-printed ring micromixers for the production of size-controllable and monodispersed LNPs with a high mRNA delivery efficiency. The effects of flow rate and ring shape asymmetry on the mixing performance were initially examined. Furthermore, the physicochemical properties (such as hydrodynamic diameter, polydispersity, and encapsulation efficiency) of the generated LNPs were quantified as a function of these physical parameters via biochemical analysis and cryo-electron microscopy imaging. With a high production rate of 68 mL/min, our 3D-printed ring micromixers can be used to manufacture LNPs with diameters less than 90 nm, low polydispersity (<0.2), and high mRNA encapsulation efficiency (>91%). Despite the simplicity of the ring-shaped mixer structure, we can produce mRNA-loaded LNPs with exceptional quality and high throughput, outperforming costly commercial micromixers.

Biomimetic Leaf-Shaped Wedge Structure with Mixed Wettability for Fog Harvesting.

Water scarcity is a pressing issue in arid and semi-arid regions, making fog harvesting a promising method for water collection. However, enhancing the rate of fog harvesting remains a challenge. Controlling the movement of droplets on functional surfaces is crucial for the development of effective water-harvesting devices. In this study, a three-dimensional (3D) fog-harvesting device with mixed wettability is fabricated using a combination of physical and chemical techniques. With inspiration drawn from natural organisms, such as the desert beetle and Nephrolepis cordifolia, which can both live in low humidity, a copper substrate with a leaf-shaped wedge superhydrophilic structure and flat superhydrophobic regions is fabricated for fog harvesting. The modified surface results in a maximum 49.89% improvement in fog-harvesting efficiency compared to the original copper substrate. The synergistic effect of the 3D structure and mixed wettability of this study offers an idea for improving fog collection efficiency, with potential implications for energy sustainability water resources.