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Digital resilience and firm internationalization: a study of Chinese listed companies
Purpose:
The aim of this research is to explore the impact of digital resilience on firms' international performance. Using internal operation efficiency and innovation as channel variables, this paper explores the relationship between digital resilience and international firm performance of Chinese listed firms.
Design/methodology/approach:
The research design follows a quantitative approach. Using firm-level panel data from 2007 to 2020, this paper tests the hypotheses between digital resilience and international firm performance through internal efficiency and innovation.
Findings:
The results note that digital resilience has a positive effect on internationalization while operation efficiency is a channel through which digital resilience promotes internationalization. Digital resilience also facilitates innovation by improving research and development (R&D) efficiency and matching innovation collaborators.
Originality/value:
This paper is one of the first to explore digital resilience in the context of internalization and international firm performance. This paper extends the notion of resource-based view (RBV) to examine the relationship between digital resilience, internal efficiency and innovation on international firm performance.The National Social Science Fund of China, "Research on the Mechanism and Policy of Market Integration driven by Digital Economy under the New Development Pattern" (22CJY065
Design of a pipeline for satellite-aided capture at the giant planets of the solar system
For orbiters aiming at the outer planets of our solar system, most of the ∆V cost is associated with the final insertion at the targeted planet. An efficient way of reducing this cost is using flybys of the moons of the planet to reduce the energy of the orbit at arrival, called satellite-aided capture. Designing a full transfer from the Earth to an outer planet, including multiple gravity assists and satellite-aided capture raises important issues that must be addressed. One of them is the multiple control parameters that are required to compute such a trajectory. These parameters must be varied over a large array of values to guarantee that all possibilities are covered with enough precision, ensuring that the final trajectory is the best possible. Current approaches on satellite-aided capture mainly focus on designing trajectories inside the sphere of influence of the targeted planet, with no or minimal focus on linking it to the interplanetary trajectory. However, it remains to create a full pipeline to compute a transfer trajectory from the Earth to an outer planet of the solar system using multiple gravity assists and satellite-aided capture. This paper will focus on creating such a pipeline for orbiters targeting Jupiter, Saturn, Uranus, and Neptune. First, different multiple gravity assists sequences are computed, allowing to make a choice based on transfer time and ∆V cost. This is obtained with a multi-objective dynamic programming exploration, allowing to capture optimal Pareto fronts of ∆V and time of flight in limited computational effort. This transfer sets initial conditions of the satellite-aided capture. Multiple capture sequences are computed around these initial conditions allowing to choose the one minimizing the insertion ∆V . Finally, the last branch of the interplanetary transfer is modified to meet the updated initial conditions of the interplanetary transfer. To compute the satellite-aided capture, the branches between the moons of the sequences are simulated using Lambert arcs. The flybys are approximated as discrete events and are computed to meet the conditions set by the previous and following branches. This pipeline is capable of reproducing scenarios of previous missions to Jupiter and Saturn, ensuring proper functioning of the code. It can also be used to design new trajectories for orbiter at Uranus and Neptune, which have only been visited by Voyager 2 during flybys
Design of novel Sb2S3/Polythiophene heterojunction for efficient adsorption and methanol sensing
Eliminating micropollutants in trace concentrations in water bodies is crucial and challenging due to their persistent and bioactive characteristics. Due to these characteristics, their detection and removal pose a challenge to the conventional removal methods and to the health of the community. To effectively remove the pollutants, it requires the design and development of an efficient technique compared to the conventional techniques. The design of highly efficient methanol sensor and the adsorption of micropollutants by a heterojunction involving Sb2S3 and polythiophene (PTh) looks promising. The adsorption study was targeted on RhB dye whereas methanol was targeted to sensing application. Sb2S3 nanoparticles was synthesized by hydrothermal methods and incorporated into thiophene solution during chemical oxidative polymerization of thiophene. The heterojunction was applied to remove RhB dye through the adsorption process. Freundlich isotherm model and Langmuir isotherm model were used to study the adsorption of RhB. The higher adsorption capacity was found in case of Sb2S3/PTh is 99.8 mg g−1, and the rate constant (K2) was found to be 0.0206 min−1. The catalysts follows the pseudo-first and second order kinetics in the removal of RhB dye. The rate constant for adsorption k1 is 0.1347 min−1 and the rate constant for diffusion is 0.297 min−1. Moreover, the PTh/Sb2S3 shows an effective methanol sensing up to 0.7 mM and the current response at 0.6756 V of the oxidation peaks shows the presence of methanol
Investigating the influence of sulphur amendment and temperature on microbial activity in bioremediation of diesel-contaminated soil
This study investigated the effectiveness of incorporating sulphur (S) with nitrogen (N) and phosphorus (P) for enhancing microbial activity in diesel-contaminated soil during ex-situ bioremediation. While N and P amendments are commonly used to stimulate indigenous microorganisms, the potential benefits of adding S have received less attention. The study found that historically contaminated soil with a moderate concentration of total petroleum hydrocarbons (TPH; 1270 mg/kg) did not have nutrient limitation, and incubation temperature was found to be more critical for enhancing microbial activity. However, soil spiked with an additional 5000 mg/kg of diesel showed increased activity following NP and NPS amendment. Interestingly, NPS amendment at 10 °C resulted in higher microbial activity than at 20 °C, indicating the potential for a tailored nutrient amendment approach to optimize bioremediation in cold conditions. Overall, this study suggests that incorporating S with N and P can enhance microbial activity in diesel-contaminated soil during ex-situ bioremediation. Furthermore, the study highlights the importance of considering incubation temperature in designing a nutrient amendment approach for bioremediation, especially in cold conditions. These findings can guide the design and implementation of future effective bioremediation strategies for petroleum hydrocarbon-contaminated soil.The authors thank ERS and the BBSRC NIBB's Environmental Biotechnology Network, (EBNET, grant reference BB/S009795/1) for funding this research project
Achieving a columnar-to-equiaxed transition through dendrite twinning in high deposition rate additively manufactured titanium alloys
The coarse β-grain structures typically found in titanium alloys like Ti–6Al–4V (wt pct, Ti64) and Ti–6Al–2Sn–4Zr–2Mo–0.1Si (Ti6242), produced by high deposition rate additive manufacturing (AM) processes, are detrimental to mechanical performance. Certain modified processing conditions have been shown to lead to a more refined grain structure, which has generally been attributed to a change in the solidification conditions with respect to the experimental Hunt diagram proposed by Semiatin and Kobryn. It is shown that with Wire Arc AM (WAAM) increasing the wire feed speed (WFS) is effective in promoting a columnar-equiaxed transition (CET). Conversely, estimates of the dendrite-tip undercooling using the KGT model suggest that this will be too small for free nucleation without the addition of artificial nucleants, due to the very low solute partitioning in Ti alloys. It is also shown that it is difficult to promote a CET with plasma transferred arc WAAM as computational fluid dynamics (CFD) melt-pool simulations indicate that the solidification parameters remain within the columnar region on the Semiatin-Kobryn Hunt map, within the constraints of a stable process. However, a high fraction of twin boundaries was observed in the refined β-grain structures seen at high WFS. This has been attributed to departure of {001}β alignment from the direction of maximum thermal gradient, caused by the curvature of the fusion boundary, stimulating dendrite twinning during solidification. In addition, it is shown that increasing the WFS leads to a change in melt-pool geometry and a reduction of remelt depth, which promoted dendrite twinning and grain refinement.The authors are appreciative of the EPSRC program grants NEWAM (EP/R027218/1) and LightForm (EP/R001715/1), for supporting aspects of this research. The authors acknowledge the use of equipment associated with the Advanced Metals Processing and Characterization themes of the Henry Royce Institute for Advanced Materials, funded through EPSRC grants EP/R00661X/1, EP/S019367/1, EP/P025021/1, and EP/P025498/1. P.B. Prangnell is grateful to the Royal Academy of Engineering, UK, and Airbus for supporting his research through the Airbus-University of Manchester Centre for Metallurgical Excellence
Automated Microfluidic Analysis of CUP-2 UOC for Forensic Applications
Poster contribution to the Defence and Security Doctoral Symposium 2023 EPSR
Critical assessment of the lattice Boltzmann method for cavitation modelling based on single bubble dynamics
The lattice Boltzmann Method (LBM) is recognised as a popular technique for simulating cavitation bubble dynamics due to its simplicity. In the validation of LBM results, the Rayleigh-Plesset (R-P) equation is commonly employed. However, most studies to date have neglected the impact of simulation settings on the predictions. This article sets out to quantify the impact of LBM domain size and bubble size, and the initial conditions of the R-P equations on the predicted bubble dynamics. First, LBM results were validated against the classical benchmarks of Laplace’s law and Maxwell’s area construction. LBM results corresponding to these fundamental test cases were found to be in satisfactory agreement with theory and previous simulations. Secondly, a one-to-one comparison was considered between the predictions of the LBM and the R-P equation. The parameters of the two models were matched based on careful considerations. Findings revealed that a good overlap between the predictions is observable only under certain conditions. The warming-up period of the LBM simulations, small domain size, and small bubble radius were identified as key factors responsible for the measured differences. The authors hope that the results will promote good simulation practices for cavitation simulation including both single bubbles and bubble clusters
Supporting data for 'An insight into the hormonal interplay regulating pigment changes and colour development in the peel of ‘Granny Smith’, ‘Opal®’ and ‘Royal Gala’ apples'
This data set contains physiological (colour, size, total soluble content) and biochemical data (including plant hormones, indivicual sugars, anthocyanins) of three different apple cultivars. It also includes the gene expression of gene involved in the ethylene pathway.Spanish Agencia Estatal de Investigacio
Simulating enhanced vertiport management in a multimodal transportation ecosystem
The advanced air mobility (AAM) industry envisions a transformative transportation ecosystem for passengers and cargo deliveries. Nonetheless, coordinating large volumes of new aerial vehicles necessitates innovative unmanned aircraft system (UAS) traffic management (UTM) solutions, supported by a robust vertiport infrastructure. Moreover, AAM will form part of a broader multimodal ecosystem, posing additional technical, procedural and operational challenges. This work thereby presents a simulation tool in AnyLogic for deploying, training and testing collaborative and intelligent AAM decision-making frameworks within a multimodal transportation system. The platform integrates multiple vertiports with diverse resource constraints, and offers a flexible solution to investigate the impact of different vertiport designs, layouts and procedures. AAM-specific influences are also introduced, including electric vehicle batteries, heterogeneous vehicle specifications, stricter flight envelopes, and hyper-local micro-weather variations. The model further acknowledges the complex inter-dependencies within a multimodal environment to capture fluctuating travel demands and dynamic passenger flows within transportation terminals. This scalable simulation tool thereby enables the development of enhanced vertiport management and AAM traffic coordination solutions, and facilitates exploratory research on multimodal coordination amongst air, ground, rail and sea transportation systems.The research work disclosed in this publication is partially funded by the Malta Tertiary Education Scholarships Scheme, and by Innovate UK under grant agreement No.10023201, as part of the Air Mobility Ecosystem Consortium (AMEC) project