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Artificially Engineered Nonlinear Circular Dichroism with Chiral Nanoscrolling of 2D Materials
No full textPublisher Copyright: © 2025 American Chemical Society.Nonlinear chiroptical response, particularly nonlinear circular dichroism (CD), holds significant potential for advancing nanotechnology, biophotonics, and molecular imaging. While conventional approaches rely on intrinsic chiral materials, we demonstrate a novel strategy to engineer this effect by transforming achiral two-dimensional (2D) transition-metal dichalcogenides (TMDs) into chiral nanostructures. By scrolling monolayer TMDs into geometrically chiral nanoscrolls, we achieve pronounced nonlinear CD (up to 0.8), evidenced by circular-polarization-dependent second-harmonic generation (SHG). Notably, the SHG-CD degree is tailored by controlling the nanoscrolls’ scrolling axes, demonstrating, for the first time, programmable chirality-dependent nonlinear responses in TMD nanoscrolls. Furthermore, the confined electromagnetic fields within the scrolled geometry amplify the SHG intensity by up to 100-fold compared to monolayers. This chiral nanoscrolling is anticipated to enable innovative functionalities in the realm of compact nonlinear light sources and modulators, heralding a new era of advanced photonic applications.Peer reviewe
China’s eight water risks
No full textPublisher Copyright: © 2025 Informa UK Limited, trading as Taylor & Francis Group.China, as a large and geographically heterogeneous country, is subject to a high diversity and blend of water-related stressors, hazards, and societal conditions. We analysed the exposure and vulnerability of the population of continental China to eight major water stresses (variability, overuse, groundwater problems, floods, droughts, organic pollution, salinity, eutrophication). This gridded high-resolution geospatial analysis employs the multiplicative risk scheme of the Sendai Framework and IPCC (risk = stress × exposure × vulnerability) together with multivariate statistical analysis. The results unveiled five distinct zones in continental China, each with a characteristic risk profile.Peer reviewe
Review of energy efficiency and technological advancements in data center power systems
No full textIn order to support a wide range of applications and services, data centers are crucial components of contemporary computer infrastructure. Nevertheless, the rapid expansion and functioning of these entities have resulted in notable energy usage and ecological consequences. Power usage effectiveness, dependability, and operating costs are all impacted by electricity supply systems, which are crucial to the operating and energy efficiency of data centers. This review article offers a thorough summary of the state of the art in data center power supply systems research, covering case studies, best practices, developing technologies, and potential directions for future investigation. The study begins with a survey of energy-efficient data centers and an outline of power usage effectiveness design concerns. The categorization of electricity supply systems is discussed through various integration strategies with renewable sources of electricity generation. This includes identifying scenarios where data centers operate in countries with a 100% fossil fuel electricity matrix, strategies for implementing clean energy purchase contracts, and investments in both on-site and off-site renewable energy projects. The review of the literature addresses current research on data center power systems, emphasizing significant discoveries and patterns in the field while pointing out gaps and restrictions. The assessment also looks at new developments in energy storage, power management, and renewable energy integration. The research, which draws from case studies of effective energy supply systems in data centers, offers useful suggestions and best practices for planning, executing, and overseeing data center power systems. The paper ends with recommendations for further study and application.Peer reviewe
Data-driven ship typical operational conditions : A benchmark tool for assessing ship emissions
No full textPublisher Copyright: © 2024 Elsevier LtdAnalysing operational conditions of ships presents a novel approach to assessing emission levels, motivated by the inadequacy of traditional static weighting factors, such as ISO 8178-E3 cycle, to capture the dynamic and complex operating characteristics of ships at sea. This study introduces a data-driven method to construct and validate ship typical operational conditions. The method encompasses identifying ship motion states, extracting features, compressing time series data based on these features, and performing cluster analysis. It has been applied to process over 12.6 million data points, demonstrating its applicability to a large dataset. The results indicate that by using actual measurement data and the proposed methodology, three typical operational conditions for ships were successfully established. There are significant differences in the feature parameters among these conditions, highlighting the distinct characteristics of each operational state. The validity of the constructed typical operational conditions was confirmed through a validation process, which involved analysing the differences in feature parameters and comparing the probability distributions of speed and acceleration to the overall dataset. Additionally, energy consumption and emission levels calculated using the typical conditions were validated through comparison with real-world data from upstream and downstream voyages. This study providing a novel tool for assessing emissions in the maritime industry.Peer reviewe
Impact of minimum viable product on software ecosystem failure
No full textPublisher Copyright: © 2024 Elsevier B.V.Context: Companies are interested in building successful value-producing ecosystems together to offer end users a broader digital service offering and better meet customer needs. However, most ecosystems fail in the early years. Objective: We investigated one small software ecosystem from the planning phase to the operative phase, where the participating companies left one by one because the software ecosystem was unsuccessful, and the software ecosystem ended after four operative years. The software ecosystem provided a digital service offering based on the defined MVP (Minimum Viable Product). That is why we were interested in understanding the MVP's impact on the ecosystem's failure. Method: We conducted a case study, the results of which are based on the semi-structured interviews of eight representatives of the software ecosystem. Results: This study showed that the actors prioritized out functionalities from the MVP, and the MVP was no longer based on the defined value proposition, target customer groups, and customer paths. It was then difficult for the actors to achieve their objectives. The companies’ commitment depended on the set objectives, and when the objectives were not achieved, the actors left the ecosystem, and the software ecosystem failed. Conclusion: The results show that the MVP can significantly affect the failure of the small software ecosystem, where all actors have a keystone role. The MVP largely defines what kind of digital service offering the software ecosystem provides and whether the actors can achieve the objectives, especially their sales goals. Thus, prioritizing the functionalities of the MVP is a critical activity.Peer reviewe
Steric aging analysis of rejuvenated recycled asphalt binders and mixtures during one-year of storage time
No full textPublisher Copyright: © 2024 Elsevier LtdSteric hardening, a gradual time-dependent phenomenon in asphalt binders, is crucial to study as it influences the long-term performance of recycled asphalt pavements. The type of rejuvenator plays a significant role in mitigating this hardening by restoring the properties of aged binders. However, since the behavior of asphalt as a thin film over aggregates differs from that of bulk binder, it is essential to evaluate steric hardening at both binder and mixture levels. This study investigates the effects of steric hardening in recycled binders and mixtures stored for 12 months at 25°C, focusing on different rejuvenators and their Saturates, Aromatics, Resins, and Asphaltenes (SARA) compositions. Using a 60/70 grade base binder with 40 % Reclaimed Asphalt Pavement (RAP), Rejuvenator B (with 92 % resin content) led to a 44 % increase in stiffness, while Rejuvenator A (rich in saturates) limited hardening to 27 %. The progression of steric hardening followed a polynomial trend over time. The consistent rise in Indirect Tensile Stiffness Modulus (ITSM) across temperatures demonstrated its effectiveness in evaluating long-term hardening effects. These findings provide critical insights into selecting appropriate rejuvenators to control steric hardening and improve the durability of recycled asphalt pavements.Peer reviewe
Combined tensile and shear behavior of perfobond connectors embedded in UHPC with a new orthotropic rubber ring
No full textPublisher Copyright: © 2024 Elsevier LtdThe uneven distribution of shear forces in shear connectors arranged in multiple rows and columns could cause issues of fatigue and durability in composite structures. In many practical applications, the shear connectors bear not only large shear forces but also considerable tensile forces. To improve the uneven shear distribution in perfobond connector (PBL) groups without significantly damaging their tensile performance, a new orthotropic rubber ring that can be easily installed on PBLs was proposed. Firstly, the tests for the tensile, shear, and combined tensile and shear behavior of PBLs embedded in ultra-high performance concrete (UHPC) with and without orthotropic rubber rings were conducted. The test results showed that orthotropic rubber rings could effectively reduce the shear stiffness of PBLs but inconsiderably affect the tensile performance. Secondly, a refined finite element (FE) model involving the fracture of perforating rebars was established and validated by the test results. The shear and tensile mechanisms of the new rubber ring PBLs were discussed. Further, a parametric study including 240 models was performed to investigate the effects of hole diameters, embedded depths, opening angles of rubber rings, and tensile force ratios. The results indicated that the shear capacity of PBLs decreased almost linearly with tensile force ratios. Finally, the shear capacity equation of PBLs under the effects of tensile forces and rubber rings was proposed by a regression analysis. Besides, an equivalent projected area method was proposed to derive the reduction factor of shear stiffness considering the effects of opening angles of rubber rings and tensile force ratios.Peer reviewe
Connections between multiple-objective programming and weight restricted data envelopment analysis : The role of the ordering cone
No full textPublisher Copyright: © 2024 Elsevier B.V.This paper explores some new, important and interesting connections between Multiple-Objective Programming (MOP) and Data Envelopment Analysis (DEA). We show that imposing weight restrictions in DEA corresponds to changing the ordering cone in MOP in a specific way. The new ordering cone is constructed and its properties are proved, providing useful insights about the connections between MOP and DEA. After providing several theoretical results, we illustrate them on a real-world data set. In addition to their theoretical appeal, our results hold significant practical importance for several reasons which are addressed in the paper.Peer reviewe
Numerical investigation of synergistic effects of nanopulsed plasma and water addition on hydrogen combustion and NO emissions
No full textPublisher Copyright: © 2025 The AuthorsThis study presents a novel integrated approach using nanopulsed repetitively pulsed discharge (NRPD) plasma with H2/H2O/Air mixtures to overcome high NO emissions and ignition delay timing (IDT) in hydrogen combustion, utilizing zero-dimensional ChemPlasKin simulations and Design of Experiments (DoE). A key finding is that while water vapor inhibits conventional autoignition, plasma-assisted ignition (PAI) is insensitive to water, as plasma dissociates H2O into reactive radicals (H, O, OH), effectively turning water into an ignition promoter and enhancing early radical formation. PAI achieves significantly lower flame temperatures (12.3 % reduction) and approximately 58 % lower NO emissions compared to conventional autoignition through non-thermal chemical pathways. Comparative analysis quantified that plasma kinetic effects play a dominant role in reducing IDT, contributing substantially more to enhancement than plasma thermal effects alone. Furthermore, the sensitivity analysis of NO formation revealed that water vapor significantly alters the kinetics of NO-related reactions, changing the sensitivity and role of key pathways like H + NO2 ⇌ NO + OH, suggesting water can reverse certain reactions from producing NO to consuming it. This plasma-water synergy successfully broadens and stabilizes low-NO combustion regimes.Peer reviewe
Nested smoothing algorithms for inference and tracking of heterogeneous multi-scale state-space systems
No full textMulti-scale problems, where variables of interest evolve in different time-scales and live in different state-spaces, can be found in many fields of science. Here, we introduce a new recursive methodology for Bayesian inference that aims at estimating the static parameters and tracking the dynamic variables of these kind of systems. Although the proposed approach works in rather general setups, for clarity we analyze the case of a heterogeneous multi-scale model with 3 time-scales (static parameters, slow dynamic state variables and fast dynamic state variables). The proposed scheme, based on a nested filtering methodology of [27], combines three intertwined layers of filtering techniques that approximate recursively the joint posterior probability distribution of the parameters and both sets of dynamic state variables given a sequence of partial and noisy observations. We explore the use of both sequential Monte Carlo schemes and several Kalman filtering techniques in the different layers of the methodology to obtain approximations of the posterior probability distributions of interest. Some numerical results are presented for a stochastic two-scale Lorenz 96 model with unknown parameters.Peer reviewe