Intermediate Solution Research Articles

Analyzing Engine Exhaust Gas Temperature Pulsations and Gas-Dynamics Using Thin-Wire Thermocouples

Abstract The exhaust of internal combustion engines (ICEs) is characterized by rapid large amplitude exhaust gas temperature (EGT) pulsations that demand high-bandwidth measurements for accurate instantaneous and mean EGTs. While measurement technique challenges constrain on-engine EGT pulse measurements, reduced-order system simulations numerically estimate the EGT pulse and its mean to overcome the measurement limitation. Notwithstanding high-bandwidth pressure measurements, model calibration and validation for the EGT are confined to mean indications using sheathed thermal sensors like thermocouples and resistance thermometers. These EGT measurements are susceptible to errors caused by heat transfer, flow unsteadiness, and the thermal inertia of the sensor. Exposed thin-wire thermocouples provide an intermediate solution to the robustness-to-response tradeoff of thermal sensors. While the thermocouples' thermal inertia significantly affects the measured EGT pulse, the signal derivative (unscaled dynamic error) provides greater insight by indicating the EGT waveform. This study utilizes a 50.8-μm Type-K thermocouple to contrast the exhaust pressure and EGT pulses through the measured signal and its derivative. Experiments in a single-pipe exhaust of a heavy-duty diesel engine with isolated engine speed and load sweeps (LS) present significant differences between the pressure and indicative EGT waveforms. It also highlights a rapid prepulse fluctuation unique to the EGT pulse waveform caused by exhaust gas-dynamics and impacted by heat transfer. The study motivates the need for increased bandwidth EGT measurements to improve model validation of EGT pulse estimates while showcasing the utility of thin-wire thermocouples.

Structural Distortion in the Wadsley-Roth Niobium Molybdenum Oxide Phase Triggering Extraordinarily Stable Battery Performance.

Wadsley-Roth niobium oxide phases have attracted extensive research interest recently as promising battery anodes. We have synthesized the niobium-molybdenum oxide shear phase (Nb, Mo)13 O33 with superior electrochemical Li-ion storage performance, including an ultralong cycling lifespan of at least 15000 cycles. During electrochemical cycling, a reversible single-phase solid-solution reaction with lithiated intermediate solid solutions is demonstrated using in situ X-ray diffraction, with the valence and short-range structural changes of the electrode probed by in situ Nb and Mo K-edge X-ray absorption spectroscopy. This work reveals that the superior stability of niobium molybdenum oxides is underpinned by changes in octahedral distortion during electrochemical reactions, and we report an in-depth understanding of how this stabilizes the oxide structure during cycling with implications for future long-life battery material design.

An efficient numerical method for the anisotropic phase field dendritic crystal growth model

In this paper, we propose and analyze an efficient numerical method for the anisotropic phase field dendritic crystal growth model, which is challenging because we are facing the nonlinear coupling and anisotropic coefficient in the model. The proposed method is a two-step scheme. In the first step, an intermediate solution is computed by using BDF schemes of order up to three for both the phase-field and heat equations. In the second step the intermediate solution is stabilized by multiplying an auxiliary variable. The key of the second step is to stabilize the overall scheme while maintaining the convergence order of the stabilized solution. In order to overcome the difficulty caused by the gradient-dependent anisotropic coefficient and the nonlinear terms, some stabilization terms are added to the BDF schemes in the first step. The second step makes use of a generalized auxiliary variable approach with relaxation. The Fourier spectral method is applied for the spatial discretization. Our analysis shows that the proposed scheme is unconditionally stable and has accuracy in time up to third order. We also provide a sophisticated implementation showing that the computational complexity of our schemes is equivalent to solving two linear equations and some algebraic equations. To the best of our knowledge, this is the cheapest unconditionally stable schemes reported in the literature. Some numerical examples are given to verify the efficiency of the proposed method.

How and when do Pt- and Pd-semimetal minerals crystallize from saturated sulfide liquids?

Platinum and Pd-arsenides, antimonides, tellurides, bismuthinides, and sulfides are the major hosts of Pt and Pd in magmatic and hydrothermal Cu-Ni-sulfide ores. Textural relationships among such minerals in nature often provide contradictory messages about the mechanism and timing of their formation. To know how and when Pt and Pd mineral phases crystallize from sulfide-saturated liquids and how their compositions and textures evolve during cooling, we undertook controlled cooling experiments in evacuated silica tubes. A Cu-Ni-Fe sulfide mixture, similar in composition to the average Merensky Reef sulfide magma, was charged (in a 9:1 wt.% proportion) with one of the PtAs2, PtTe2, PtSb2, PtBi2, PdAs2, PdTe2, PdSb, and PdBi2 compounds, heated to 1,100°C, and slowly cooled (15°C/day) to room temperature. The run products were sampled at 950°C, 750°C, and 25°C by quenching the silica tubes in water. The results show that Pt formed stable phases with As, Te, and Sb above 950°C and with Bi and S below 750°C. The Pt phases were found mostly in the decomposed intermediate solid solution (ISS), and all the phases survived to 25°C with no compositional changes. At 950°C, Pd formed arsenide, telluride, and antimonide immiscible melts that coexisted with monosulfide solid solution (MSS) and sulfide melt. The composition of the Pd-semimetal melt droplets changed during cooling by equilibration with the host sulfide. Palladium mineral phases formed at temperatures below 750°C directly from the immiscible semimetal-rich melts where they kept the rounded shapes of the melt droplets. Ni-sulfarsenides preceded the formation of Pd arsenides. No Ni tellurides, antimonides, or bismuthinides formed in any of the systems, implying that their formation requires higher semimetal/Pt + Pd ratios. The decomposition of MSS and ISS to base metal sulfides led to significant textural changes in Pt and Pd mineral grains. The compositions of Pt and Pd phases are inherited from the magmatic stage, and their textures are low-temperature (<450°C) features.

Charge transport in electrospinning of polyelectrolyte solutions.

This study elucidates the electrical charge transport during electrospinning of weak polyelectrolyte (poly(acrylic acid) (PAA)) solutions by employing current emission measurements. With pH variation, the PAA ionization degree could be controlled from uncharged at low pH to weakly charged at intermediate solution pH. Electrospinning neutral poly(vinylpyrrolidone) (PVP) as a reference polymer solution confirmed established current-flow rate scaling relationships as shown by De La Mora and Loscertales (1994), I ∼ (γKQ)ν, independent of the applied electric field polarity, where ν = 0.5, K is the conductivity, γ is the surface tension, Q is the flow rate, and I is the current. Similarly, the uncharged PAA did not display any polarity dependence, yet ν ≈ 0.8. Negatively charged PAA, however, showed a marked deviation in the current-flow rate behavior, which was affected by the applied electric field polarity. In the case of negative polarity, ν = 0.99, whereas for a positive polarity ν = 0.68. Similarly, the voltage required for stable cone-jet electrospinning of charged PAA was significantly higher in the negative polarity configuration for all tested flow rates (300-1600 μL h-1). As opposed to merely surface charges typically considered when electrospinning leaky dielectric fluids, as suggested by Melcher and Taylor (1969), our results suggest that the measured current is also affected by volumetric charges from charged PAA in the bulk of the jet. The proposed additional charge transport might affect the orientational order within PE-based nanofibers and their diameter.

TRENDS IN THE DEVELOPMENT OF SOIL CULTIVATION TECHNOLOGIES IN THE MOUNTAINOUS CONDITIONS OF THE REPUBLIC OF ARMENIA IN THE CONTEXT OF ENVIRONMENTAL ISSUES

The main reasons for the reduction of plowing volumes worldwide have been presented, among which, especially for the conditions of the Republic of Armenia, the high energy costs and negative environmental consequences have been highlighted particularly the large volumes of slope erosion, excessive soil compaction under tractor tracks, and the formation of a compacted plow pan layer, which negatively affects plant growth and development. Alternative soil cultivation technologies have been discussed specifically minimum and zero tillage. Several other technologies that do not have widespread application have also been considered. A comparative analysis of new and old soil cultivation technologies has been conducted. It has been clarified that the duration of scientific research related to minimum and zero tillage does not exceed 10-12 years; therefore, a logical question has arisen: is it possible to permanently apply no-till cultivation technologies? The idea of minimizing the damage inflicted on the agro-ecosystem has been set as the basis for choosing soil cultivation technologies. By combining the positive and negative aspects of different plowing and no-till cultivation technologies, an intermediate solution has been proposed: to perform plowing periodically once every 3-5 years (depending on soil-climatic conditions) and to mitigate the negative consequences of plowing, it is planned to perform it only with combined machines equipped with a plow. An environmental assessment of the proposed combined machine has been provided. For this purpose, indicators such as soil loss, mechanical and wind erosion, as well as mechanical soil degradation have been selected. For the latter, soil compaction under tractor tracks has been considered. Using the patterns developed in previous scientific research on mechanical soil degradation, it has been clarified that when using the proposed combined machine, the soil density under tractor tracks will decrease by about 0.17 g/cm³, as a result of which the yield will increase by up to 14%, and during slope cultivation (mechanical erosion) by about 60 cm. Wind erosion will also be significantly reduced.

Interactive Design-of-Experiments: Optimizing a Cooling System.

The optimization of cooling systems is important in many cases, for example for cabin and battery cooling in electric cars. Such an optimization is governed by multiple, conflicting objectives and it is performed across a multi-dimensional parameter space. The extent of the parameter space, the complexity of the non-linear model of the system, as well as the time needed per simulation run and factors that are not modeled in the simulation necessitate an iterative, semi-automatic approach. We present an interactive visual optimization approach, where the user works with a p-h diagram to steer an iterative, guided optimization process. A deep learning (DL) model provides estimates for parameters, given a target characterization of the system, while numerical simulation is used to compute system characteristics for an ensemble of parameter sets. Since the DL model only serves as an approximation of the inverse of the cooling system and since target characteristics can be chosen according to different, competing objectives, an iterative optimization process is realized, developing multiple sets of intermediate solutions, which are visually related to each other. The standard p-h diagram, integrated interactively in this approach, is complemented by a dual, also interactive visual representation of additional expressive measures representing the system characteristics. We show how the known four-points semantic of the p-h diagram meaningfully transfers to the dual data representation. When evaluating this approach in the automotive domain, we found that our solution helped with the overall comprehension of the cooling system and that it lead to a faster convergence during optimization.

Hydraulic Characterization of Permeable Materials Used for Filling Mole Drain Channels in Structurally Unstable Soils

Highlights Permeable materials can be used to fill mole drains and provide support to the cavity walls in structurally unstable soils. Permeable materials extend the lifespan and improve the hydraulic performance of mole drainage systems. Darcy’s law for nonlinear porous flow explained the hydraulic performance of the permeable materials used in this study. A numerical method was established to assess the suitability of permeable materials of unknown hydraulic performance. Design guidelines were developed to assist in the planning of filled mole drainage systems installed in structurally unstable soils. Abstract. Mole drainage in soils with low permeability is a cost-effective technique for managing soil drainage. Following installation, the satisfactory performance of the system will depend on having sufficient soil fissure development extending from the soil surface to the roof of the mole channel and mole channel stability to avoid its collapse. Permeable materials such as river-run gravel and crushed stone can be used to fill mole channels to prevent channel collapse in halomorphic and high-silt content (e.g., 50%–70%) soils and extend the lifespan of the system. The objectives of this work were to: (i) characterize a range of permeable materials that can be used to fill mole drains and provide support to the cavity walls in structurally unstable soils; (ii) verify the applicability of Darcy’s law to explain the hydraulic performance of such materials, and (iii) develop a set of design and planning guidelines aimed at improving the performance of mole drainage systems that are filled with permeable materials. Five permeable materials were characterized, namely: three types of river-run gravels, crushed baked mud bricks, and crushed stone. The materials were characterized for their mechanical and hydraulic properties, and the applicability of Darcy’s law was experimentally determined. Small- and medium-sized gravels are easy to handle and apply during field installation due to their shape and flowability properties and the reduced risk of clogging when placed in the mole channel. However, the hydraulic performance of these materials would not allow for system designs longer than about 100 m, which therefore would limit their utilization in practice. Large-sized gravel offered an intermediate solution with overall satisfactory hydraulic performance. Crushed brick and crushed stone offered good alternatives to gravel, allowing for longer (e.g., >120 m) system designs for all combinations of drain spacing and drain gradient. However, their angularity, poor uniformity, and size range distribution can compromise the efficiency of handling and delivery in current mole plough systems. For all materials, the hydraulic conductivity (Kh) decreased with an increase in the hydraulic gradient. For a given hydraulic gradient, Kh was dependent on aggregate size, such that a larger D50 value led to increased Kh. The nonlinear performance of Darcy’s law was verified for all materials, and potential equations were fitted to represent such relationships, all showing acceptable fits to the nonlinear models (P<0.001). A linear relationship (P<0.05) between the parameter m of the potential model and total porosity was established. The set of equations developed by this study will enable estimating Kh based on the aggregate size distribution or as a function of the total porosity of the material. Crushed brick and crushed stone could provide a cost-effective solution for the installation of filled mole drain systems in structurally unstable soils. Keywords: Darcy’s law, Extreme rainfall, Halomorphic soils, Hydraulic conductivity, Reynolds number, Silty soils.

БАГАТОРІВНЕВА СИСТЕМА РОЗПІЗНАВАННЯ ОБЛИЧЧЯ

The problem of biometric person identification based on component-based face recognition is considered. It is shown that the face recognition system can be represented as a hierarchically organized multilevel system in which an ensemble of local classifiers forms “soft” decisions about the belonging of images of individual components of the face to given classes. Then, based on the integration of these decisions, the formation of the final decision on whether the recognized face belongs to one of the given classes is realized. The problems of constructing a model of a local classifier, as well as choosing an integrator of intermediate solutions of local classifiers, are formulated and solved. Keywords: pattern recognition, multilevel recognition system, classifier ensemble, classifier combination rule, decision making.

Low-Temperature Deposited SiO2 for Advanced Chiplet

D2W hybrid bonding is a crucial technology for chiplets and 3D HBMs [1]. However, the sequential die bonding process has not been matured yet, in particular due to the compatibility of process tools with high-level particle control, e.g. die level cleaning, activation, and die handling. The current packaging tools are not designed for hybrid bonding, therefore, the control of the die surface cleanliness is still far from the requirement for assembly tools compared to the wafer level tools. In order to mitigate the issues above and lead time for D2W stacking, massive D2W bonding by using a temporary carrier wafer with populated dies (so-called collective D2W bonding) is introduced as an intermediate solution. The collective D2W bonding is a promising integration method since it can be processed in matured wafer-level tools for die-level cleaning, inspection, activation, and even bonding. Furthermore, reconstructed D2W hybrid bonding is recently proposed and developed to overcome some issues seen inon collective D2W bonding, e.g. huge gap in between die. The drawback for both collective D2W and reconstructed D2W is the propagation of misalignment for chip placement on a carrier wafer and actual hybrid bonding at Wafer-to-Wafer (W2W) step. Overall, the use of organic temporary bonding materials, which are typically polymers regardless of mechanical or laser release, has some issues/limitations for collective D2W bonding. e.g. die shift during population and W2W bonding, chemical/thermal compatibility, and difficulties for chemical mechanical polishing due to the elastic properties. We proposed a newly developed temporary bonding method for die population on a carrier wafer with CVD dielectric film (Fig.1(a)) [2]. In this study, the debonding mechanism of low-temperature (150°C) deposited SiO2 (LT-SiO2) at the bonding interface was investigated. According to TDS measurement, water is the major outgas below 250°C (Fig. 1(b)). It indicates that the water outgases from LT-SiO2 are much larger than that from Thermal SiO2. The surface will become the interface after bonding, and it form voids by water outgassing by post-bond annealing. Fig. 1(C) shows the results of PAS at different annealing temperatures. The S parameter of LT-SiO2 is lower than the thermally oxidized SiO2, which can be considered that atomic-level vacancies are occupied by water and other residual substances due to low-temperature deposition [3]. The larger increase of the S parameter at the temperature range above the deposition temperature (150℃) supports this hypothesis. Also, a little increase of the S parameter near the surface suggests that water re-entered the sub-surface from the atmosphere after annealing, which is correlated with the TDS result. Moreover, when the higher annealing temperature and PAS measurement were performed, the closer S parameter of LT-SiO2 is to that of the thermally oxidized SiO2 by outgassing and densification. Furthermore, when measurements of bonding strengths after post-bond annealing (250℃) were performed, the bonding strength of LT-SiO2 (1.34[J/m2]) is lower than thermally oxidized SiO2 (4.41[J/m2]). In addition, the lower the pre-bond annealing temperature, the larger the void area and the lower the bonding strength. This can be considered that water in the LT-SiO2 that has not been fully outgassed by low-temperature pre-bond annealing is desorbed, resulting in void formation at the interface and lower bonding strength. Therefore, we can make LT-SiO2 bonding and debonding as temporary bonding by the thermal release method.[1] F. Inoue et.al., “Protective layer for collective die to wafer hybrid bonding” 2019 International 3D Systems Integration Conference (3DIC)[2] F. Inoue et.al., “Inorganic Temporary Direct Bonding for Collective Die to Wafer Hybrid Bonding” 2023 Electronic Components and Technology Conference (ECTC)[3] M. Sometani, et. al., J. Appl. Phys 51 021101 (2012) Figure 1

Optimizing insulation and heating systems for social housing in Chile: Insights for sustainable energy policies

Due to the climatic conditions in central-southern Chile, there are high heating energy consumption and PM2.5 emissions. Among the alternatives to mitigate it, the Chilean government has implemented subsidies to improve the housings envelope and to replace firewood stoves by pellet stoves and air-to-air heat pumps. Accordingly, for evaluating the effectivity of above-mentioned initiatives, this study proposes to identify the optimal solutions that minimize the energy demand, the environmental impacts, and the global costs, for social housing using different insulation materials and heating systems in four Chilean cities located in central-southern Chile. Results reveal pellet stoves with lower environmental impacts but higher global costs, while heat pumps offer an intermediate solution that can be enhanced with a greener electricity grid, but the global costs are still too high. Firewood stoves could be optimal solution depending on optimization weighting factors. The study emphasizes prioritizing housing envelope improvements in energy policies, followed by heating system enhancements. Although replacing firewood poses challenges due to costs, it is crucial for Chile's 2050 decarbonization goal. This research provides valuable insights into the complexities and potential solutions for transitioning away from firewood in Chilean social housing.

Long-term results (after a mean 11.3 years, and up to 22 years, of follow-up) of the Legacy Constrained Condylar Knee (LCCK™) in primary total knee arthroplasty

IntroductionThe use of a sliding prosthesis in total knee arthroplasty (TKA) with increased stress is an intermediate solution in primary surgery, between posteriorly stabilized prostheses and hinged prostheses, in cases of ligamentous laxity and/or loss of bone substance. Favorable results have been reported in the medium term but to our knowledge, this type of prosthesis has not been evaluated in Europe beyond 10 years of follow-up. We therefore conducted a retrospective study in order to carry out: 1) the study of the survival of the Legacy Constrained Condylar Knee (LCCK™) prosthesis in primary surgery, 2) the analysis of complications, functional scores and radiographic data, 3) the analysis of the link between the diaphyseal filling rate and prosthetic loosening. HypothesisThe LCCK™ sliding prosthesis with increased constraint has equivalent long-term survival and clinical results to standard posteriorly stabilized TKA and superior to hinged TKA. Material and methodA retrospective series of 141 LCCK™ implanted in 134 patients between 1997 and 2010 was analyzed. Survival was assessed with censoring through an evaluation of partial or total revision of the implants. The functional results were evaluated using the IKS and Oxford 12 scores. Data regarding the Canal Fill Ratio (CFR) and the presence of pathological periprosthetic lines were also collected. ResultsThe average follow-up was 11.3±5.3years with a maximum follow-up of 22.7years. Survival at 20years was 90.8% [95% CI: 83.7–95.7]. The rate of early complications was 13.5% (19/141), predominantly comprised of venous thrombosis (6/141), hematomas (3/141 including two requiring surgical drainage), stiffness (3/141) and early infections (3/141). The rate of late complications was 17% (24/141), led by stiffness (4.4%; 6/141), infections (2.9%; 4/141) and hardware failure (2. 2%; 3/141). Ten of the 141 patients (7.1%) had LCCK failure, including 3 (2.1%) for stiffness, 3 (2.1%) for hardware failure, 2 (1.4%) for infection, 1 (0.7%) for laxity and 1 (0.7%) for a periprosthetic fracture. No aseptic loosening was found. The total IKS score went from 65 [0–116] to 143 [79–200] at follow-up, the IKS knee score went from 30 [0–66] to 85 [44–100], and the IKS function score went from 35 [0–70] to 57 [0–100]. The Oxford score went from 14 [2–25] to 34 [15–48] at follow-up. Only two patients (1.4%) presented with a partial periprosthetic line. The tibial CFR was 0.81 and the femoral CFR was 0.76. The influence of the CFR could not be analyzed due to the absence of loosening. DiscussionThe LCCK™ prosthesis in primary surgery has good medium-term survival, a significant improvement in functional scores and a complication rate comparable to posteriorly stabilized prostheses. The complication rate is lower than that of hinged prostheses. Level of evidenceIV; single-center retrospective study.

Estimating geodynamic model parameters from geodetic observations using a particle method

SUMMARY Bayesian-based data assimilation methods integrate observational data into geophysical forward models to obtain the temporal evolution of an improved state vector, including its uncertainties. We explore the potential of a variant, a particle method, to estimate mechanical parameters of the overriding plate during the interseismic period. Here we assimilate vertical surface displacements into an elementary flexural model to estimate the elastic thickness of the overriding plate, and the locations and magnitudes of line loads acting on the overriding plate to produce flexure. Assimilation of synthetic observations sampled from a different forward model than is used in the particle method, reveal that synthetic seafloor data within 150 km from the trench are required to properly constrain parameters for long wavelength solutions of the upper plate (i.e. wavelength ∼500 km). Assimilation of synthetic observations sampled from the same flexural model used in the particle method shows remarkable convergence towards the true parameters with synthetic on-land data only for short to intermediate wavelength solutions (i.e. wavelengths between ∼100 and 300 km). In real-data assimilation experiments we assign representation errors due to discrepancies between our incorrect or incomplete physical model and the data. When assimilating continental data prior to the 2011 Mw Tohoku-Oki earthquake (1997–2000), an unrealistically low effective elastic plate thickness for Tohoku of ∼5–7 km is estimated. Our synthetic experiments suggest that improvements to the physical forward model, such as the inclusion of a slab, a megathrust interface and viscoelasticity of the mantle, including accurate seafloor data, and additional geodetic observations, may refine our estimates of the effective elastic plate thickness. Overall, we demonstrate the potential of using the particle method to constrain geodynamic parameters by providing constraints on parameters and corresponding uncertainty values. Using the particle method, we provide insights into the data network sensitivity and identify parameter trade-offs.

On vortex-sheet evolution beyond singularity formation

We consider the evolution of a spatially periodic, perturbed vortex sheet for small times after the formation of a curvature singularity at time $t=t_c$ as demonstrated by Moore (Proc. R. Soc. Lond. A, vol. 365, issue 1720, 1979, pp. 105–119). The Moore analysis is extended to provide the small-amplitude, full-sheet structure at $t=t_c$ for a general single-mode initial condition in terms of polylogarithmic functions, from which its asymptotic form near the singular point is determined. This defines an intermediate evolution problem for which the leading-order, and most singular, approximation is solved as a Taylor-series expansion in $\tau = t-t_c$ , where coefficients are calculated by repeated differentiation of the defining Birkhoff–Rott (BR) equation. The first few terms are in good agreement with numerical calculation based on the full-sheet solution. The series is summed, providing an analytic continuation which shows sheet rupture at circulation $\varGamma =0^+$ , $\tau >0^+$ , but with non-physical features owing to the absence of end-tip sheet roll up. This is corrected by constructing an inner solution with $\varGamma < \tau$ , as a perturbed similarity form with small parameter $\tau ^{1/2}$ . Numerical solutions of both the inner, nonlinear zeroth-order and first-order linear BR equations are obtained whose outer limits match the intermediate solution. The composite solution shows sheet tearing at $\tau =0^+$ into two separate, rolled up algebraic spirals near the central singular point. Branch separation distance scales as $\tau$ with a non-local, $\tau ^{3/2}$ correction. Properties of the intermediate and inner solutions are discussed.

What starts with laughter ends in tears: Invasive alien species regulations should not hinder scientific research

AbstractBiological invasions represent one of the major threats to the world's biodiversity. National and international efforts are taken to address the complexity and dynamic of invasions in legislation. However, based on the Polish experience of implementing the European Union's regulation on invasive alien species (IAS), we suggest that an unclear and disorganized process of law implementation results in the regulations being counterproductive. We describe how a well‐planned policy can become a burden impeding effective research and, consequently, scientific feedback to improve the policy. The results of our study suggest that there is a large scale of scientists' noncompliance with new legal requirements. For many researchers, the implementation of the new IAS regulation was changing the rules in the middle of the game. Researchers strictly following the new regulations must wait for the relevant permits and may risk the successful completion of their projects. Conversely, researchers who prioritize project completion may be forced to continue their research violating the law. We argue that this example of implementing the new IAS regulation illustrates the need to include some intermediate solutions providing more flexibility and time for researchers to adjust to policy change, thus minimizing the negative impacts of the new legislature on scientific progress.

One-Shot Generative Prior in Hankel-k-Space for Parallel Imaging Reconstruction.

Magnetic resonance imaging serves as an essential tool for clinical diagnosis. However, it suffers from a long acquisition time. The utilization of deep learning, especially the deep generative models, offers aggressive acceleration and better reconstruction in magnetic resonance imaging. Nevertheless, learning the data distribution as prior knowledge and reconstructing the image from limited data remains challenging. In this work, we propose a novel Hankel-k-space generative model (HKGM), which can generate samples from a training set of as little as one k-space. At the prior learning stage, we first construct a large Hankel matrix from k-space data, then extract multiple structured k-space patches from the Hankel matrix to capture the internal distribution among different patches. Extracting patches from a Hankel matrix enables the generative model to be learned from the redundant and low-rank data space. At the iterative reconstruction stage, the desired solution obeys the learned prior knowledge. The intermediate reconstruction solution is updated by taking it as the input of the generative model. The updated result is then alternatively operated by imposing low-rank penalty on its Hankel matrix and data consistency constraint on the measurement data. Experimental results confirmed that the internal statistics of patches within single k-space data carry enough information for learning a powerful generative model and providing state-of-the-art reconstruction.

Electrical manipulation of a single electron spin in CMOS using a micromagnet and spin-valley coupling

For semiconductor spin qubits, complementary-metal-oxide-semiconductor (CMOS) technology is a promising candidate for reliable and scalable fabrication. Making the direct leap from academic fabrication to qubits fully fabricated by industrial CMOS standards is difficult without intermediate solutions. With a flexible back-end-of-line (BEOL), functionalities such as micromagnets or superconducting circuits can be added in a post-CMOS process to study the physics of these devices or achieve proofs-of-concept. Once the process is established, it can be incorporated in the foundry-compatible process flow. Here, we study a single electron spin qubit in a CMOS device with a micromagnet integrated in the flexible BEOL. We exploit the synthetic spin orbit coupling (SOC) to control the qubit via electric fields and we investigate the spin-valley physics in the presence of SOC where we show an enhancement of the Rabi frequency at the spin-valley hotspot. Finally, we probe the high frequency noise in the system using dynamical decoupling pulse sequences and demonstrate that charge noise dominates the qubit decoherence in this range.

Exploring Effectiveness of Relationship Marketing on Artificial Intelligence Adopting Intention

The major contribution of present study is to revisit how consumer obtain high adoption intention of artificial intelligence (AI)’s production/service based on symmetric and asymmetric thinking in data analysis. In recent years, technology involving AI has become key technology for success worldwide and has received prominence among academics and practitioners. Accordingly, it is necessary to identify the relationships among relationship marketing, AI perceived usefulness, perceived ease of use, perceived risk, and adoption intention. The main contribution of the symmetric approach (i.e., SEM, structure equation modeling) is to test the research hypothesis to determine the net effect between the variables, and asymmetric approach (i.e., fsQCA, fuzzy set qualitative comparative analysis) contributes to the identification of sufficient conditions leading to high level adoption intention in the concept of fuzzy sets. With symmetric approach, results of path analysis of SEM indicate that impacts of trust are greater than that of commitment. Similarly, perceived usefulness of AI has a greater impact on the adoption intention. Furthermore, AI perceived risk is negative associate with adoption intention. With asymmetric approach, intermediate solutions from fsQCA show that there are three sufficient conditions for high adoption intention of AI. For instance, one of configurations or sufficient conditions is trust, commitment, and AI perceived usefulness present but perceived ease of use absent.

Three birds with one stone: Full-component recovery of strongly acidic arsenic complex wastewater via combining electro-redox and electrodialysis

Full-component green recovery of As-contained acid wastewater shows great prospect demanding on both urgent resource need and environment protection. In this work, we firstly constructed a three-chamber electrochemical system for full-component recovery of As-Cu acidic wastewater, combining electrochemical redox and electrodialysis techniques to recover metals and acids simultaneously. In which CeO2@CC and Cu plate electrode materials were selected and the middle chamber was separated by cation-exchange membrane (CEM) and anion-exchange membrane (AEM). In the anode chamber, 93.84% As(III) was oxidized and adsorbed by the CeO2@CC anode within 2 h. Meanwhile, 100% copper was reduced and deposited on the cathode. The pH of the intermediate chamber solution was reduced to 1.2. Besides, economic benefits and carbon emission accounting indicated that the system has better economic and environmental benefits for the full-component recovery of As-Cu strongly acidic wastewater. This work brings a new insight in future wastewater resource recovery and purification.

Testing re-optimisation strategies in international kidney exchange programmes by the ENCKEP simulator

We tested re-optimisation strategies for international kidney exchange programmes using the simulator developed by the ENCKEP COST Action. Kidney exchange programmes (KEPs) are operating in most of the European countries to facilitate the exchange of kidney donors for the recipients with incompatible living donors. The optimal solutions for national and international KEPs are typically selected in every three months based on the compatibilities estimated on the individual immunological data. However, these estimations are not always accurate, and if a positive crossmatch is found in the laboratory crossmatch tests then the corresponding exchange cycle (or chain) must be cancelled. Depending on the matching process, the coordinators may use different re-optimisation strategies to repair the failed solutions. We examine the effects of using multiple rounds of re-optimisation with different optimisation strategies, such as fixing good cycles in the intermediate solutions or prioritising transplants with negative crossmatch tests in previous rounds. In the context of international KEPs we also consider the possibility of testing and prioritising national transplants in the solutions. We measure the performance of these policies regarding the number of transplants and the number of compatibility tests conducted in a time period. By extending our results presented in [16], we performed simulations for a large number of instances to measure the effects of various re-optimisation policies. Our main findings show a clear trade-off in the number of transplants versus the number of tests and re-optimisation rounds.