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Engaging Customers, Embracing AI: How Suppliers Respond to Trade Tensions and Improve Performance
No full textAcademic Summary: Firms face intensifying pressure to innovate amid escalating US–China trade tensions. This study investigates how they integrate artificial intelligence (AI) to respond to such disruptions. We reconceptualize induced innovation theory as adversity‐induced innovation theory and test hypotheses using data from listed Chinese manufacturing firms, WTO tariff records, and customs data (2015–2022). Results indicate that higher tariff exposure increases AI integration, particularly among firms with stronger customer engagement needs. AI integration improves supply chain efficiency, sales performance, and market value. However, performance benefits follow an inverted U‐shape: extreme tariff exposure diminishes AI's compensatory effects. The study extends induced innovation theory to geopolitical adversities and advances stakeholder engagement theory by identifying customer engagement as a boundary condition for technology adoption. We establish causal relationships between tariff‐induced AI integration and firm performance through instrumental variable analysis and robustness checks. Findings inform how firms can strategically use technological innovation and customer collaboration to strengthen resilience under external shocks. Managers should view trade tensions as catalysts for AI integration rather than merely as obstacles. Managerial Summary: Firms facing trade tensions should view them as catalysts for strategic AI integration rather than merely as obstacles. Our research shows that firms experiencing higher tariff exposure that invest in AI achieve measurable improvements in supply chain efficiency, sales performance, and market valuations. However, AI's compensatory benefits diminish at extreme tariff levels, revealing an optimal investment threshold that managers should consider. The benefits of AI integration are particularly strong for firms with high customer engagement needs, such as those with concentrated customer bases, substantial international sales, or significant customer‐specific investments. To maximize returns, managers should prioritize AI technologies that strengthen customer relationships by enhancing communication, responsiveness, and service personalization during trade disruptions. Successful implementation requires navigating technical and organizational challenges, including talent acquisition, data quality concerns, and integration complexities. Despite these hurdles, our findings confirm AI's strategic value as a compensatory innovation tool that not only mitigates tariff impacts but also transforms supplier‐customer relationships. By aligning AI initiatives with customer engagement objectives, firms can turn geopolitical adversity into a competitive advantage. Companies that integrate AI strategically can maintain operational continuity, preserve market position, and emerge stronger from trade disruptions
Radiation damage to the Hubble Space Telescope during two Solar cycles, and correction of Charge Transfer Inefficiency using ArCTIc
No full textFrom 2002 to 2025, the Hubble Space Telescope's Advanced Camera for Surveys has suffered in the harsh radiation environment above the protection of the Earth's atmosphere. We track the degradation of its image quality, as Solar protons and galactic cosmic rays have damaged its photosensitive charge-coupled device (CCD) imaging sensors. The rate of damage in low Earth orbit is modulated by 18.5 +4.5 −0.5 per cent during an 11 year Solar cycle, peaking 430 +11 −5 days after Solar minimum as recorded in the number of sunspots. The type of damage is consistent with defects in the silicon lattice that have all stabilised into one of three configurations. We also present the open-source Algorithm for Charge Transfer Inefficiency correction (ArCTIc) v7, available from https://github.com/jkeger/arctic. This models the (instantaneous or gradual) capture of photoelectrons into lattice defects, and their release after (a discrete set or continuum of) characteristic time delays, which creates spurious trailing in an image. Calibrated using the trailing of hot pixels, and applied during post-processing of astronomical images, ArCTIc can correct 99.5% of Charge Transfer Inefficiency trailing averaged over the camera's lifetime, and 99.9% of trailing in the worst-affected recent data
Measuring the stellar-to-halo mass relation at ∼10 10 solar masses, using forthcoming space-based imaging of galaxy–galaxy strong lenses
No full textThe stellar-to-halo mass relation (SHMR) is central to understanding the co-evolution of galaxies and their host dark matter haloes, yet it remains weakly constrained for dwarf galaxies owing to their faintness, especially beyond the Local Group. Strong gravitational lensing offers a unique probe of the SHMR at subgalactic scales and cosmological distances, as the masses of subhaloes within the main lens can be inferred from the perturbations they imprint on lensed images. Anticipating the discovery of galaxy–galaxy strong lenses by forthcoming facilities such as Euclid, we perform an end-to-end simulation to forecast Euclid’s constraints on the SHMR at the halo mass scale of . We generate mock Euclid Visible Camera images of lens systems hosting a fiducial subhalo and vary its properties to assess the robustness of mass inference. We find that Euclid’s angular resolution cannot break the intrinsic mass–concentration degeneracy of subhaloes, nor deblend the light of satellite galaxies (when present) associated with them, leading to biased inferred halo masses. These limitations can be overcome with high-resolution follow-up imaging from facilities such as the Hubble Space Telescope, enabling accurate halo-mass measurements.We forecast that a statistical sample of such systems, combining lensing-derived halo masses with stellar masses from photometric spectral energy distribution fitting, can constrain the SHMR at dwarf-galaxy scales with a precision of dex in halo mass and dex in stellar mass, enabling powerful tests of galaxy formation theories
Tip-tilt retrieval using trilateration of a sodium laser guide star
No full textTip, tilt (TT) and focus modes cannot be directly measured from a laser guide star (LGS). For optical communications, residual TT errors in the pre-compensation of a ground-to-satellite optical communications link will lead to beam wander, resulting in signal fades at the receiver. We describe a method for retrieving the full TT solely with LGSs. This method uses trilateration, in which the differential arrival times of a pulsed LGS at ≥3 detectors at different locations around the laser transmitter are used to find the position of the LGS, and therefore the TT from only the uplink path of the LGS. We study the feasibility of this method and the technological developments needed to enable it. The simulation results show that, given a detector with a timing resolution tres =10−12 s, and ≥ 108 photons s−1 are collected at each detector, the tip and tilt modes can be measured to an accuracy of θ ≈ 0.45 arcsec. For pre-compensation to a low earth orbit (LEO) satellite, this can increase the power received at the satellite by over 2 dB when compared to pre-compensation using the TT from the downlink beam
Wireless Channel Map Enabled Instantaneous Channel State Information Acquisition in High-Mobility Scenarios
No full textHigh-mobility and large-bandwidth applications at high frequencies make the acquisition of doubly-selective channels costly and complex, as the fast fading channel causes a surge in pilot overheads and inter-carrier interference. Accurate estimation of the complex channel gain (CG) and the carrier frequency offset (CFO) is required to support subsequent high-accuracy channel prediction that alleviates the heavy pilot burden. The emerging technology of the wireless channel map (WCM) can approximately reproduce the actual propagation environment digitally with customized channel parameters, offering an opportunity to accurately estimate the complex CG and CFO. In this paper, a WCM-based prior distribution construction method and a joint complex CG and CFO estimation algorithm are proposed. Specifically, a parameterized linear estimation problem for the complex CG is generated based on a nonuniform delay-domain off-grid channel representation, and with more realistic prior distributions constructed by the knowledge from the WCM-provided angular-delay power spectrum density, the joint estimation problem is solved under the Bayesian inference framework. Simulation results demonstrate the superiority of the proposed algorithm, with a better performance in terms of estimation accuracy and bit error rates (BER) than existing baselines. It is also verified that the proposed WCM-based algorithm is highly adaptable to different WCM precision and robust to different user speeds
Projecting Chlorophyll-a distributions under climate change using Copula-based inference and SST projections
No full textSea surface temperature (SST) and chlorophyll-a (Chl-a) are key indicators of marine ecosystem productivity, particularly for small pelagic species that are sensitive to climate-driven environmental changes. This study investigates the coupled dynamics of SST and Chl-a in two ecologically distinct regions, the Alboran Sea (AS) and the North Atlantic Moroccan Ocean (NAMO), to better understand their response under future climate scenarios. Historical satellite observations from MODIS-Aqua and projections from six Coupled Model Intercomparison Project Phase VI (CMIP6) General Circulation Models (GCMs) are analyzed under two Shared Socioeconomic Pathways (SSP2-4.5 and SSP5-8.5). Multivariate bias correction (MBCp) is performed to correct systematic biases in the model outputs. While GCMs effectively capture SST trends, they show significant limitations in simulating Chl-a variability. To address this issue, we introduce a conditional copula-based inference framework that links SST and Chl-a distributions based on their joint probabilistic behavior. In addition, marginal distributions are identified using goodness-of-fit tests, AIC and BIC. The copula families have been selected based on AIC, taking into account regional and seasonal variability. Conditional simulations from fitted copulas, informed by future SST projections, are used to predict Chl-a levels under climate change. However, the method is initially validated during the historical period using historical SST models, confirming the robustness of the approach. Results highlight a pronounced divergence between the optimistic and the pessimistic scenarios, suggesting a consistent reduction of the most productive phases that sustain higher trophic levels. This decline in productivity indicates that the far future ocean will not merely be a warmer version of the present system but a biogeochemically altered and less resilient ocean, characterized by lower productivity and reduced variability. Regionally, the NAMO region is projected to undergo a gradual yet persistent weakening. In contrast, the AS region is projected to face two contrasting futures, partial resilience under an optimistic scenario or a potential catastrophic ecological transition under a pessimistic scenario
Tuning Circular Dichroism and Circularly Polarised Luminescence in Single Crystals of a Perylene Diimide Macrocycle
No full textChiral materials that manipulate circularly polarised light have burgeoning applications across optoelectronics, sensing and information encoding, yet the functionality of organic molecular materials is often limited by their relatively low dissymmetry factors (gabs/lum 700 nm). An effective strategy to amplifying gabs/lum is to optimise the chiral arrangement of chromophores, with single crystals providing intrinsic molecular ordering. Herein, we quantify the circular dichroism and circularly polarised luminescence of single crystals of a chiral L‐valinol bis‐perylene diimide macrocycle by Mueller–Matrix polarimetry and circularly polarised luminescence microscopy, as required for the analysis of such anisotropic materials. Through this, we see that organic crystals are valuable for understanding how supramolecular structure can be used to modify the sign, strength and energy of the chiroptical signal. Indeed, by tuning the macrocycle's π–π stacking interactions, our materials deliver strong chiroptical properties (gabs/lum > 10−2), including circularly polarised luminescence into the near infrared (λ = 780 nm)
Comparative molecular dynamics simulations of charged solid–liquid interfaces with different water models
No full textAqueous solid–liquid interfaces (SLIs) are ubiquitous in nature and technology, often hosting molecular-level processes with macroscopic consequences. Molecular dynamics (MD) simulations offer a tool of choice to investigate interfacial phenomena with atomistic precision, but there exists a large number of water models, each optimised for a different purpose. Here we compare the ability of common water models to accurately simulate the interface between a charged silica surface and an aqueous solution containing NaCl. We first compare the bulk dielectric constant of water and its dependence on salt concentration for SPC/Fw, SPC/e, TIPS3p, H2O/DC, TIP3P-Fw, OPC3, TIP3P, TIP3P-FB, TIP3P-ST, FBA/e, and TIPS3p-PPPM, revealing large variations between models. Simulating the interface with silica for the most suitable water models (SPC/Fw, H2O/DC, TIP3-ST and TIPS3p-PPPM) shows some intrinsic consistency with continuum predictions (Poisson–Boltzmann) whereby the free energy minima obtained from MD simulations and the analytical model are in agreement, provided the latter includes the MD-determined total charge of ions in the Stern layer and dielectric constant. This consistency stands even for water models with a dielectric constant off by 100%. For salt concentrations higher than 0.21 M NaCl, the formation of random ion–ion pairs limits the reproducibility of the MD results and the applicability of the analytical method. The results highlight the applicability of the analytical model down to the nanoscale, provided a priori knowledge of the Stern layer charge is available. The findings could have significant implications for MD simulations of SLIs, especially at charged or electrified interfaces
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