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Dynamic real-time workshop scheduling on job arrival is critical for effective production. This study proposed a dynamic shop scheduling method integrating deep reinforcement learning and convolutional neural network (CNN). In this method, the spatial pyramid pooling layer was added to the CNN to achieve effective dynamic scheduling. A five-channel, two-dimensional matrix that expressed the state characteristics of the production system was used to capture the state of the real-time production of the workshop. Adaptive scheduling was achieved by using a reward function that corresponds to the minimum total tardiness, and the common production dispatching rules were used as the action space. The experimental results revealed that the proposed algorithm achieved superior optimization capabilities with lower time cost than that of the genetic algorithm and could adaptively select appropriate dispatching rules based on the state features of the production system. [ABSTRACT FROM AUTHOR]

Erbium-doped GaN (Er:GaN) quasi-bulk crystals are emerging as a promising novel gain medium for high energy lasers emitting at the retina-safe wavelength window of 1.5 μm. We report the polarization-resolved photoluminescence (PL) emission spectroscopy studies, which revealed that the pumping efficiency with the excitation polarization parallel to the c-axis of GaN (E ⇀ | | c ⇀) is significantly higher than that with the excitation polarization perpendicular to the c-axis of GaN (E ⇀ ⊥ c ⇀). This phenomenon is a direct consequence of the inherent polar wurtzite GaN lattice, giving rise to a net local field, surrounding each Er ion, along the c-axis of GaN. The temperature dependent behaviors of the PL emission spectra were explained in terms of the Boltzmann population distributions among sublevels within the 4I15/2 ground state and the 4I13/2 first excited state of Er3+ in GaN, thereby providing an improved understanding regarding the origin of the dominant emission lines observed near 1.5 μm. The results suggested that the polarization field in GaN can be exploited to enhance the effective Er excitation cross section by manipulating the polarization of the excitation light source. [ABSTRACT FROM AUTHOR]

Objectives: Most human in‐vivo placental imaging techniques are unable to distinguish and characterize various placental compartments, such as the intervillous space (IVS), placental vessels (PV) and placental tissue (PT), limiting their specificity. We describe a method that employs T2* and diffusion‐weighted magnetic resonance imaging (MRI) data to differentiate automatically placental compartments, quantify their oxygenation properties and identify placental lesions (PL) in vivo. We also investigate the association between placental oxygenation patterns and fetal brain oxygenation. Methods: This was a prospective study conducted between 2018 and 2021 in which dual‐contrast clinical MRI data (T2* and diffusion‐weighted MRI) were acquired from patients between 20 and 38 weeks' gestation. We trained a fuzzy clustering method to analyze T2* and diffusion‐weighted MRI data and assign placental voxels to one of four clusters, based on their distinct imaging domain features. The new method divided automatically the placenta into IVS, PV, PT and PL compartments and characterized their oxygenation changes throughout pregnancy. Results: A total of 27 patients were recruited, of whom five developed pregnancy complications. Total placental oxygenation level and T2* did not demonstrate a statistically significant temporal correlation with gestational age (GA) (R2 = 0.060, P = 0.27). In contrast, the oxygenation level reflected by T2* values in the placental IVS (R2 = 0.51, P = 0.0002) and PV (R2 = 0.76, P = 1.1 × 10−7) decreased significantly with advancing GA. Oxygenation levels in the PT did not show any temporal change during pregnancy (R2 = 0.00044, P = 0.93). A strong spatial‐dependent correlation between PV oxygenation level and GA was observed. The strongest negative correlation between PV oxygenation and GA (R2 = 0.73, P = 4.5 × 10−7) was found at the fetal‐vessel‐dominated region close to the chorionic plate. The location and extent of the placental abnormality were automatically delineated and quantified in the five women with clinically confirmed placental pathology. Compared to the averaged total placental oxygenation, placental IVS oxygenation level best reflected fetal brain oxygenation level during fetal development. Conclusion: Based on clinically feasible dual‐MRI, our method enables accurate spatiotemporal quantification of placental compartment and fetal brain oxygenation across different GAs. This information should improve our knowledge of human placenta development and its relationship with normal and abnormal pregnancy. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Pseudodynamic (PD) method is a novel method that has the merit of considering the temporal and spatial effects of earthquake input in seismic stability analysis. Currently, most PD analyses adopted the two-dimensional (2D) plane-strain assumption, which is inconsistent with the fact that many slope collapses have distinct three-dimensional (3D) features. To address that, a 3D PD method was proposed in this paper for rock slopes yielding Hoek–Brown criterion. The present method was established on the one-block mechanism in the kinematic analysis, since this mechanism has considerable efficiency in 3D safety factor computation. The details of the 3D PD method are elaborated herein, including failure mechanism, energy balance equation, and strategy of fining solutions. The effects of temporal–spatial variation of seismic input on slope stability are discussed using the proposed approach. The study reveals that phase change and acceleration amplification have contrary effects on rock slope stability, and which factor dominates determines whether PD analyses result in overestimated or underestimated safety factors than classical PS analyses. Finally, a parametric study is performed to investigate the influences of rock strength, slope geometry, and earthquake parameters in PD analysis. [ABSTRACT FROM AUTHOR]

With the gradual increase of car ownership, the road traffic environment in diversion areas has become more complicated, resulting in the increase of abnormal driving behaviors and the high frequency of traffic accidents. Therefore, it is necessary to accurately determine driving behaviors to reduce the frequency of traffic accidents. In order to accurately determine the driving behaviors, a method for determining the abnormal driving behaviors in diversion areas based on group intelligence perception of network of vehicles is proposed. Firstly, the group intelligence perception data collection method is used to obtain driving behavior data, and a elliptic filter is used to eliminate noises in the driving behavior data. Secondly, a sliding window is introduced to extract driving behavior characteristics and typical driving behavior characteristics, and an abnormal driving behavior judgment model is established based on support vector mechanism. Finally, the model is trained based on sample data to determine the optimal parameters and complete the judgment of abnormal driving behaviors. Experimental results show that the minimum error frequency of driving behavior judgment obtained by the proposed method is 2.8%, which fully proves that the proposed method can accurately judge driving behaviors. [ABSTRACT FROM AUTHOR]

Patients that undergo radiation therapy (RT) for locally advanced non-small cell lung cancer (NSCLC) have different pre-treatment risk factors and treatment-related risk factors that may ultimately affect their long-term cardiovascular health. We examined whether detrimental cardiac-related outcomes, disease progression, and death are associated with aforementioned risk factors. We performed a retrospective review of patients ≥18 years old with Stage III NSCLC that received RT 01/01/2010-03/01/2022. Demographics, pre-treatment and treatment-related risk factors, and cardiac-related outcomes (major adverse cardiac event (MACE - defined as cardiac death, unstable angina, MI, HF hospitalization or coronary revascularization), new diagnosis of hypertension or arrhythmia) were collected. Logistic regression models were used to create univariable and multivariable analyses (MVA) between risk factors and 1) cardiac-related outcomes, 2) progression-free survival (PFS), and 3) overall survival (OS). 221 patients who had Stage III NSCLC were identified, with a median age of 74 years, 52% male, 48% female, 89.1% current/former smokers with 30 median pack-years. 115 (52.0%) had stage IIIA disease, 98 (44.3%) had stage IIIB disease, and 8 (3.6%) had stage IIIC disease. All patients received RT, 50 (22.6%) received surgery, 216 (97.7%) received chemotherapy. No studied risk factors were significant for MACE or new diagnosis of hypertension. Receiving surgery as part of treatment was found to be significant for a new diagnosis of arrhythmia on MVA (OR 4.00, 95%CI 1.38-11.88, p=0.011). No studied risk factors were significant for PFS. The mean radiation dose on the heart was found to be significant for OS (mean heart dose for alive patients 933 cGy vs 1198 cGy for patients who experienced death, OR 1.0, 95%CI 1.0-1.0, p=0.024). Smoking pack-years trended to significance for OS (OR 1.02, 95%CI 1.0-1.04, p=0.062). In this single institution retrospective study, we find that Stage III NSCLC treated with RT who also received surgery as part of treatment were associated with significantly higher risk of the new diagnosis of arrhythmia following treatment, and mean radiation dose on the heart is significantly associated with overall survival. In the emerging era of neoadjuvant chemo(immune)therapy, further work to understand the mechanisms behind how different NSCLC treatment modalities affect the heart is needed. [ABSTRACT FROM AUTHOR]

Age-hardenable 2000- and 7000-series aluminium alloys share the ability to achieve outstanding combinations of high specific strength and fracture toughness without including expensive alloying elements such as scandium. Using laser surface melting (LSM), we investigate the suitability of two commercial, high-strength aluminium alloys (ultimate tensile strength ≥ 600 MPa) for laser powder bed fusion (L-PBF). It is revealed that solidification cracks form in both, the third-generation Al-Cu-Li alloy 2065 and the high-Zn containing alloy 7034, with the latter having a lower crack density. Through a combination of microstructural characterisation by SEM, EDS, and EBSD, residual stress analysis and quantitative hot cracking criteria, we deduce that alloy 2065 shows greater potential for L-PBF application despite its slightly higher crack density after LSM. Through laser surface alloying, the composition of alloy 2065 was systematically varied in terms of titanium and copper content to improve its cracking resistance. It is found that the formation of solidification cracks is suppressed by the addition of 2 – 4 wt% Ti, whereas the introduction of copper has little effect. Our study suggests that Ti-modified 2065 is an attractive alloy for L-PBF. It could potentially join the existing high-strength aluminium feedstock materials available for L-PBF. [Display omitted] [ABSTRACT FROM AUTHOR]

Aim: To develop a radiomics model to predict the muscle-invasive status of bladder cancer (BC) in contrast-enhanced computed tomography (CECT) images, compared with radiologists' interpretations.Materials and Methods: One hundred and eighty-eight CECT images with histopathologically confirmed BC were retrieved retrospectively from November 2018 to December 2019 and were divided randomly into the training (n=120) and test dataset (n=68). The BC were annotated manually and validated on the venous phase by a general radiologist and an experienced radiologist, respectively. The radiomics analysis included radiomics feature extraction and model development. The same images were also evaluated by two radiologists. The diagnostic performance of radiomics was evaluated using receiver operating characteristic (ROC) curve analysis and the area under the ROC curve (AUC), sensitivity, and specificity were calculated. The predictive performance of radiomics was then compared to visual assessments of the two radiologists.Results: The radiomics model reached an AUC (95% confidence interval [CI]) of 0.979 (0.935-0.996) and 0.894 (0.796-0.956) in the training and test dataset, respectively. The radiomics model outperformed the visual assessment of radiologist A and B both in the training (0.865 [0.791-0.921], 0.894 [0.824-0.943]) and test dataset (0.766 [0.647-0.860], 0.826 [0.715-0.907]). Pairwise comparisons showed that the specificities of the radiomics model were higher than the radiologists (85.3-96.7% versus 47.1-58.3%, all p<0.05), but the sensitivities were comparable between the radiomics and the radiologists (79.4-90% versus 91.2-96.7%; all p>0.05).Conclusions: A radiomics model was developed that outperformed the radiologists' visual assessment in predicting the muscle-invasive status of BC in the venous phase of CT images. [ABSTRACT FROM AUTHOR]

We investigate the laser ionization process taking place when the CO molecule is exposed to vacuum ultraviolet (VUV) radiation resonant with the CO A¹Π(v = 0) ← X¹Σ+(v = 0) transition around 154 nm, along with the ultraviolet (UV) and visible (Red) radiation used to generateVUVby four-wave difference-frequency mixing. By measuring the CO+ ion recoil and a room temperature gas spectrum, it is possible to assign the ionization process as 1 + 1′ + 1″ REMPI where the one-photon steps refer to the VUV, UV, and Red radiation, respectively. Resonance enhanced ionization of rotational states around J = 12 arise due to the overlap of the fixed wavelength UV (∼250 nm) with the R band-head of a transition assigned to CO E¹Π(v = 6) ← A¹Π(v = 0) with a term value of 104 787.5 cm-1. The REMPI process is efficient and polarization sensitive and should be useful in a wide range of studies involving nascent CO. [ABSTRACT FROM AUTHOR]

Pathways for formation of C+ and O+ ions when applying (2 + 1) resonance enhanced multiphoton ionization (REMPI) of CO via the B¹Σ+ and E¹Π electronic states are characterized with the velocity map imaging technique. By employing an unskimmed pulsed valve, it was possible to obtain sharp images for a wide range of initial CO J-states. Most of the atomic ion production pathways could be assigned as one- or two-photon dissociation of a series of vibrational levels of the CO+ X²Σ+ and A²Π states. Large enhancements in dissociation of particular CO+ vibrational states in these progressions could be accurately assigned to accidental resonances of the REMPI laser with CO+ X²Σ+-B²Σ+ transitions. [ABSTRACT FROM AUTHOR]

Background: The use of mesh is controversial in the treatment of female pelvic organ prolapse.Objectives: To systematically review the outcomes of sacrocolpopexy compared with transvaginal mesh surgery and to provide evidence-based suggestions.Search Strategy: The MEDLINE, EMBASE, Cochrane Library and clinicaltrials.gov databases were searched on 21 November 2018.Selection Criteria: Randomised controlled trials and prospective and retrospective cohort studies were included.Data Collection and Analysis: Data were extracted by one reviewer and examined by a second reviewer for accuracy. Odds ratios and 95% CI were calculated using random-effects models.Main Results: Twenty comparative studies were included. The meta-analysis was performed with subgroups. The summary odds ratios of the randomised controlled group were 1.84 (95% CI 0.79-4.29, I2  = 75%) for anatomical success, 1.41 (95% CI 0.47-4.24, I2  = 38%) for subjective success, 0.42 (95% CI 0.18-0.98, I2  = 0%) for mesh complications, 0.61 (95% CI 0.20-1.91, I2  = 0%) for prolapse reoperation and 0.44 (95% CI 0.23-0.88, I2  = 0%) for de novo dyspareunia. The mean differences were 0.77 (95% CI 0.31-1.23, I2  = 66%) for total vaginal length and -1.28 (95% CI -2.00 to -0.55, I2  = 66%) for point C after surgery.Conclusions: Very-low-quality evidence indicated that the anatomical and subjective success rates of sacrocolpopexy were similar to those of transvaginal mesh surgery; sacrocolpopexy might be more beneficial than transvaginal mesh surgery in terms of mesh-related complication rates, prolapse recurrence and de novo dyspareunia. However, additional high-quality randomised trials with long-term follow-up durations are needed.Tweetable Abstract: Sacrocolpopexy is beneficial after surgical anatomical changes and has decreased rates of mesh-related complications and dyspareunia. [ABSTRACT FROM AUTHOR]

To evaluate whole-node histogram parameters of blood flow (BF) maps derived from three-dimensional pseudo-continuous arterial spin-labelled (3D pCASL) imaging in discriminating metastatic from benign upper cervical lymph nodes (UCLNs) for nasopharyngeal carcinoma (NPC) patients. Eighty NPC patients with a total of 170 histologically confirmed UCLNs (67 benign and 103 metastatic) were included retrospectively. Pre-treatment 3D pCASL imaging was performed and whole-node histogram analysis was then applied. Histogram parameters and morphological features, such as minimum axis diameter (M in AD), maximum axis diameter (M ax AD), and location of UCLNs, were assessed and compared between benign and metastatic lesions. Predictors were identified and further applied to establish a combined model by multivariate logistic regression in predicting the probability of metastatic UCLNs. Receiver operating characteristic (ROC) curves were used to analyse the diagnostic performance. Metastatic UCLNs had larger M in AD and M in AD/M ax AD ratio, greater energy and entropy values, and higher incidence of level II (upper jugular group), but lower BF 10th value than benign nodes (all p <0.05). M in AD, BF 10th , energy, and entropy were validated as independent predictors in diagnosing metastatic UCLNs. The combined model yielded an area under the curve (AUC) of 0.932, accuracy of 84.42 %, sensitivity of 80.6 %, and specificity of 90.29 %. Whole-node histogram analysis on BF maps is a feasible tool to differentiate metastatic from benign UCLNs in NPC patients, and the combined model can further improve the diagnostic efficacy. • Whole-node histogram parameters could act as a noninvasive effective biomarker. • A nomogram combining histogram parameters and M in AD of UCLNs was constructed. • The nomogram could serve as a novel diagnostic tool for the status of UCLNs. [ABSTRACT FROM AUTHOR]

Key message: The CcGRXS12 gene protects plants from cellular oxidative damage that are caused by both biotic and abiotic stresses. The protein possesses GSH-disulphide oxidoreductase property but lacks Fe–S cluster assembly mechanism. Glutaredoxins (Grxs) are small, ubiquitous and multi-functional proteins. They are present in different compartments of plant cells. A chloroplast targeted Class I GRX (CcGRXS12) gene was isolated from Capsicum chinense during the pepper mild mottle virus (PMMoV) infection. Functional characterization of the gene was performed in Nicotiana benthamiana transgenic plants transformed with native C. chinense GRX (Nb:GRX), GRX-fused with GFP (Nb:GRX-GFP) and GRX-truncated for chloroplast sequences fused with GFP (Nb:Δ2MGRX-GFP). Overexpression of CcGRXS12 inhibited the PMMoV-I accumulation at the later stage of infection, accompanied with the activation of salicylic acid (SA) pathway pathogenesis-related (PR) transcripts and suppression of JA/ET pathway transcripts. Further, the reduced accumulation of auxin-induced Glutathione-S-Transferase (pCNT103) in CcGRXS12 overexpressing lines indicated that the protein could protect the plants from the oxidative stress caused by the virus. PMMoV-I infection increased the accumulation of pyridine nucleotides (PNs) mainly due to the reduced form of PNs (NAD(P)H), and it was high in Nb:GRX-GFP lines compared to other transgenic lines. Apart from biotic stress, CcGRXS12 protects the plants from abiotic stress conditions caused by H2O2 and herbicide paraquat. CcGRXS12 exhibited GSH-disulphide oxidoreductase activity in vitro; however, it was devoid of complementary Fe–S cluster assembly mechanism found in yeast. Overall, this study proves that CcGRXS12 plays a crucial role during biotic and abiotic stress in plants. [ABSTRACT FROM AUTHOR]

Yeast cultures (YCs) are defined as promising feed additives that maintain the health of birds and improve growth performance by modulating gut microbiota. YCs contain effective metabolites such as glycine, fructose, inositol, galactose, and sucrose. This study investigated the effects of YCs and their effective metabolites on carcass traits and cecal microflora in broilers. A total of 280 one-day-old mixed-sex Arbor Acres broilers were randomly allocated to seven groups. The basal diet (control DZ) was supplemented with various proportions of glycine, fructose, inositol, galactose, and sucrose (Groups A, B, and C), 24-hour grown Saccharomyces cerevisiae cultures (Group D) (YC), and a commercial yeast culture product (SZ) at concentrations of 0.1% and 1% (Groups E and F). Bodyweight of broilers was correlated positively with proportions of Proteobacteria in Group C and Lactobacillus and Roseburia in Group B (P <0.05). Broilers fed diets supplemented with YC or its active metabolites had the highest proportions of bacteria involved in nucleotide metabolism, and amino acid and carbohydrate metabolism. These results suggested that the dietary addition of YC could alter the proliferation of beneficial bacteria in broilers. [ABSTRACT FROM AUTHOR]

Summary: High‐resolution imaging is an important issue in various fields of scientific researches and engineering applications. Pseudothermal ghost imaging is one of the subfields of quantum imaging, providing new capabilities beyond conventional imaging methods. Also, it can provide a new viewpoint of imaging physical mechanisms. In this review, we explain the major ideas of pseudothermal ghost imaging, restricting the very important case of high‐resolution imaging. We analyse the strategies which can significantly improve the image quality in pseudothermal ghost imaging. It may apply for merging it with common optical imaging methods in the extreme ultraviolet (XUV) or X‐ray spectral regime for driving the applications to a wider audience in bioscience and nano‐physics. [ABSTRACT FROM AUTHOR]

A third-order approximate solution for surface gravity waves in the finite water depth is studied in the context of potential flow theory. This solution corresponds to the steady-state part of a multidirectional irregular wave field and provides explicit expressions for the surface elevation, free-surface velocity potential, and velocity potential. The amplitude dispersion relation is also provided. Two approaches are used to derive the third-order analytical solution, resulting in two types of approximate solutions: the perturbation solution and the Hamiltonian solution. The perturbation solution is obtained by a classical perturbation technique in which the time variable is expanded in multiscale to eliminate secular terms. The Hamiltonian solution is derived from the canonical transformation in the Hamiltonian theory of water waves. By comparing the two types of solutions, it is found that they are completely equivalent for the first- and second-order solutions and the nonlinear dispersion, but for the third-order part only the sum–sum terms are the same. Due to the canonical transformation that could completely separate the dynamic and bound harmonics, the Hamiltonian solutions break through the difficulty that the perturbation theory breaks down due to singularities in the transfer functions when the quartet resonance criterion is satisfied. Furthermore, it is also found that some time-averaged quantities based on the Hamiltonian solution, such as mean potential energy and mean kinetic energy, are equal to those in the initial state in which the sea surface is assumed to be a Gaussian random process. This is because there are associated conserved quantities in the Hamiltonian form. All of these show that the Hamiltonian solution is more reasonable and accurate to describe the third-order steady-state wave field. Finally, based on the Hamiltonian solution, some statistics are given such as the volume flux, skewness, excess kurtosis, and non-uniqueness of the induced mean flow and mean surface. [ABSTRACT FROM AUTHOR]

A reproducible, quasi-stationary edge localized mode (ELM)-suppressed scenario was obtained over a wide range of plasma parameters by continuous injection of boron (B) powder into an upper-single null discharge in the experimental advanced superconducting tokamak [Sun et al., Nucl. Fusion 61, 014002 (2021)]. This powder-induced ELM-absent regime is associated with an edge harmonic mode (EHM) that provides continuous particle exhaust to maintain constant density without confinement degradation and impurity accumulation, the latter of which is often observed in ELM-free regimes. A flow rate threshold of B powder injection, leading to a threshold intensity of the EHM, is necessary for full ELM suppression. The fundamental harmonic of the EHM exhibits a toroidal mode number n = 1. The mode is observable in the entire poloidal cross section with a peak near the upper X-point in an upper-single null configuration. The EHM spans radially across the pedestal and scrape-off layer, peaking inside the separatrix. The EHM appears to be insensitive to q95, heating power, plasma toroidal rotation, and pedestal collisionality. [ABSTRACT FROM AUTHOR]

The minimization of the remanent magnetization of ferromagnetic materials is a prerequisite for a reproducible low magnetic field inside shields. To realistically describe this so-called magnetic equilibration procedure, this paper proposes two approaches for the calculation of time- and space-dependent fields in the presence of ferromagnetic materials like permalloy. The first method is based on the Jiles-Atherton model and also takes into account frequency dependent effects. The second method is the newly developed empirical phase shift model, tailored specially for the simulation of the equilibration procedure. Both approaches are compared to experimental tests and show good quantitative agreement. [ABSTRACT FROM AUTHOR]

Large edge-localized modes (ELMs) were mitigated by gravitational injection of lithium granules into the upper X-point region of the experimental advanced superconducting tokamak (EAST) device with tungsten plasma-facing components. The maximum ELM size was reduced by ∼70% in high βN H-mode plasmas. Large ELM stabilization was sustained for up to about 40 energy confinement times, with constant core radiated power and no evidence of high-Z or low-Z impurity accumulation. The lithium granules injection reduced the edge plasma pedestal density and temperature and their gradients, due to increased edge radiation and reduced recycling from the plasma-facing components. Ideal stability calculations using the ELITE code indicate that the stabilization of large ELMs correlates with improved stability of intermediate-n peeling-ballooning modes, due to reduced edge current resulting from the profile changes. The pedestal pressure reduction was partially offset by a core density increase, which resulted in a modest ∼7% drop in core stored energy and normalized energy confinement time. We surmise that the remnant small ELMs are triggered by the penetration of multiple Li granules just past the separatrix, similar to small ELMs triggered by deuterium pellet Futatani et al (2014 Nucl. Fusion 54 073008). This study extends previous ELM elimination with Li powder injection Maingi et al (2018 Nucl. Fusion 58 024003) in EAST because (1) use of small, dust-like powder and the related potential health hazards were eliminated, and (2) use of macroscopic granules should be more applicable to future devices, due to deeper penetration than dust particles, e.g. inside the separatrix with velocities ∼10 m s−1 in EAST. [ABSTRACT FROM AUTHOR]

With rapid development of urban rail transit, maglev trains, benefiting from its comfortable, energy-saving and environmentally friendly merits, have gradually entered people's horizons. In this paper, aiming at improving the aerodynamic performance of an urban maglev train, the aerodynamic optimization design has been performed. An improved two-point infill criterion has been adopted to construct the cross-validated Kriging model. Meanwhile, the multi-objective genetic algorithm and complex three-dimensional geometric parametrization method have been used, to optimize the streamlined head of the train. Several optimal shapes have been obtained. Results reveal that the optimization strategy used in this paper is sufficiently accurate and time-efficient for the optimization of the urban maglev train, and can be applied in practical engineering. Compared to the prototype of the train, optimal shape benefits from higher lift of the leading car and smaller drag of the whole train. Sensitivity analysis reveals that the length and height of the streamlined head have a great influence on the aerodynamic performance of the train, and strong nonlinear relationships exist between these design variables and aerodynamic performance. The conclusions drawn in this study offer the chance to derive critical reference values for the optimization of the aerodynamic characteristics of urban maglev trains. [ABSTRACT FROM AUTHOR]

Particle accumulation at liquid-liquid or liquid-gas interfaces can significantly alter capillary behavior and give rise to unusual interfacial phenomena including the asymmetric macroscopic mechanical response of the interface. This study explores the accumulation of cetyltrimethylammonium bromide-modified nanoparticles at fluid interfaces and the subsequent mechanical response of nanoparticle-coated droplets during contraction and expansion. Droplet tests involve the simultaneous recording of the droplet shape and the capillary pressure. Complementary single-pore experiments examine the response of particle-coated interfaces as they traverse a pore constriction. Interfaces promote order. The time-dependent nanoparticle accumulation at the interface is diffusion-controlled. The nanoparticle coated droplets can sustain negative capillary pressure before they buckle. Buckling patterns strongly depend on the boundary conditions: non-slip boundary conditions lead to crumples while slip boundary conditions result in just a few depressions. The particle-coated interface exhibits asymmetric behavior in response to particle-level capillary forces: an "oil droplet in a nanofluid bath" withstands a significantly higher capillary pressure difference than a "nanofluid droplet in an oil bath". A first-order equilibrium analysis of interaction forces explains the asymmetric response. Single-constriction experiments show that the formation of particle-coated interfaces has a pronounced effect on fluid displacement in porous media. [ABSTRACT FROM AUTHOR]

We report an observation of robust suppression of edge-localized modes (ELMs) in the Experimental Advanced Superconducting Tokamak (EAST), enabled by continuous boron (B) powder injection. Edge harmonic oscillations appear during B powder injection, providing sufficient particle transport to maintain constant density and avoid impurity accumulation in ELM-stable plasmas. Quasi-steady ELM suppression discharges are demonstrated with modest energy confinement improvement and over a wide range of conditions: heating power and technique variation, electron density range over a factor ∼3.5, deuterium or helium ion species, and with either direction of the toroidal magnetic field. ELM suppression is observed above a threshold edge B intensity and ceases within 0.5 s of termination of the B injection. In contrast to ELM suppression accompanied by recycling reduction during Li powder injection in NSTX and EAST (Maingi et al 2018 Nucl. Fusion 58 024003), reduced recycling due to hydrogenic species retention is unnecessary for the ELM suppression with B powder injection, paving the way for its consideration as an ELM control tool for future fusion devices. [ABSTRACT FROM AUTHOR]

Jilin Oilfield in the Songliao Basin has gone through three stages of increase, stabilization and decrease in crude oil production during the development process. In this paper, the water flooding experiment was carried out by means of rock core in series combination, to analyze and study the water flooding characteristic curve and the recovery ratio curve of the core in Jilin Oilfield. According to the experimental analysis, when the PV number changed slightly (usually 0~1), the pressure at the monitoring point and the instantaneous liquid volume increased, and the water flood front, the oil displacement efficiency and the water cut increased significantly. When the injected PV number continued to increase (PV number>1), the pressure at the monitoring point changed slowly, the water flood front, the oil output and the water cut increased slightly, and the oil displacement efficiency was low. According to the experimental results, we explored the characteristics of water flooding by means of rock core in series combination to improve the recovery ratio of the oilfield. [ABSTRACT FROM AUTHOR]

In an NFV network, the availability of resource scheduling can be transformed to the existence of the fractional factor in the corresponding NFV network graph. Researching on the existence of special fractional factors in network structure can help to construct the NFV network with efficient application of resources. Let h: E(G) → [0, 1] be a function. We write d G h (x) = ∑ e ∋ x h (e) . We call a graph Fh with vertex set V(G) and edge set Eh a fractional (g, f)-factor of G with indicator function h if g (x) ≤ d G h (x) ≤ f (x) holds for any x ∈ V(G), where Eh = {e : e ∈ E(G), h(e) > 0}. We say that G has property E(m, n) with respect to a fractional (g, f)-factor if for any two sets of independent edges M and N with ∣M∣ = m, ∣N∣ = n, and M ∩ N = ∅ , G admits a fractional (g, f)-factor Fh with h(e) = 1 for any e ∈ M and h(e) = 0 for any e ∈ N. The concept of property E(m, n) with respect to a fractional (g, f)-factor corresponds to the structure of an NFV network where certain channels are occupied or damaged in some period of time. In this paper, we consider the resource scheduling problem in NFV networks using graph theory, and show a neighborhood union condition for a graph to have property E(1, n) with respect to a fractional (g, f)-factor. Furthermore, it is shown that the lower bound on the neighborhood union condition in the main result is the best possible in some sense. [ABSTRACT FROM AUTHOR]

The vacuum ultraviolet beamline BL03U with a photon energy range from 7 eV upwards has been constructed at the 3.5 GeV Shanghai Synchrotron Radiation Facility. Equipped with an APPLE‐Knot undulator, this beamline is dedicated to angle‐resolved photoemission spectroscopy. An energy‐resolving power of higher than 4.6 × 104 has been achieved in the photon energy range 21.6–48 eV, which is almost the same as the theoretical estimation. [ABSTRACT FROM AUTHOR]

Pyrroloquinoline quinone (PQQ) is a cofactor of glucose dehydrogenase (GDH) and thus participates in glucose utilization. In Klebsiella pneumoniae, glucose utilization involves PQQ‐dependent direct oxidation pathway (DOP) and phosphoenolpyruvate‐dependent transport system (PTS). It is challenging to overproduce PQQ, as its biosynthesis remains unclear. Here, we report that PQQ production can be enhanced by stimulating the metabolic demand for it. First, we developed CRISPR interference (CRISPRi) system to block PTS and thereby intensify DOP. In shake‐flask cultivation, the strain with CRISPRi system (simultaneously inhibiting four PTS‐related genes) produced 225·65 nmol l−1 PQQ, which was 2·14 times that of wild type. In parallel, an exogenous soluble glucose dehydrogenase (sGDH) was overexpressed in K. pneumoniae. In the shake‐flask cultivation, this sGDH‐overexpressing strain accumulated 140·05 nmol l−1 PQQ, which was 1·33 times that of wild type. To combine the above two strategies, we engineered a strain harbouring both CRISPRi vector and sGDH‐overexpressing vector. In the shake‐flask cultivation, this two‐plasmid strain generated 287·01 nmol l−1 PQQ, which was 2·72 times that of wild type. In bioreactor cultivation, this two‐plasmid strain produced 2206·1 nmol l−1 PQQ in 57 h, which was 7·69 times that in shake‐flask cultivation. These results indicate that PQQ production can be enhanced by intensifying DOP, as the apo‐enzyme GDH is intrinsically coupled with cofactor PQQ. This study provides a strategy for the production of cofactors whose biosynthesis mechanisms remain ambiguous. Significance and Impact of the Study: Pyrroloquinoline quinone (PQQ) is an economically important chemical, which typically serves as a cofactor of glucose dehydrogenase (GDH) and thus participates in glucose metabolism. Klebsiella pneumoniae can naturally synthesize PQQ, but current yield constrains its commercialization. In this study, the PQQ level was improved by stimulating metabolic demand for PQQ, instead of overexpressing PQQ synthetic genes, as the synthetic mechanism remains ambiguous. [ABSTRACT FROM AUTHOR]

Summary: Clonostachys rosea is a promising saprophytic filamentous fungus that belongs to phylum Ascomycota. Clonostachys rosea is widespread around the world and exists in many kinds of habitats, with the highest frequency in soil. As an excellent mycoparasite, C. rosea exhibits strong biological control ability against numerous fungal plant pathogens, nematodes and insects. These behaviours are based on the activation of multiple mechanisms such as secreted cell‐wall‐degrading enzymes, production of antifungal secondary metabolites and induction of plant defence systems. Besides having significant biocontrol activity, C. rosea also functions in the biodegradation of plastic waste, biotransformation of bioactive compounds, as a bioenergy sources and in fermentation. This mini review summarizes information about the biology and various applications of C. rosea and expands on its possible uses. [ABSTRACT FROM AUTHOR]

A novel Ag–Nb 2 O 5 braze filler is developed and successfully tested as a sealant candidate for solid oxide cells. The resultant AgNbO 3 by the reaction between Ag and Nb 2 O 5 at high temperatures turns out to be the key to enable a desirable wetting of the YSZ by the braze filler. Typical interfacial microstructure of the YSZ/AISI 310s brazed joints are characterized by a scanning electron microscopy (SEM) and a transmission electron microscopy (TEM) with an energy dispersive spectroscopy (EDS). Effects of Nb 2 O 5 contents and joining parameters on the microstructural evolution and mechanical performance of the joints are investigated. Joints with a maximum average strength of 100–110 MPa are achieved when bonding at 1150 °C/30 min with 5 mol.% Ag–Nb 2 O 5. The long-term stability of the YSZ/Ag–Nb 2 O 5 /AISI 310s joints are evaluated in air for over 350 h at 800 °C and no cracks or cell degradation are found in the joints after the aging process, indicating that the new-developed Ag–Nb 2 O 5 is a promising candidate as the sealant for the SOFC stacks. [ABSTRACT FROM AUTHOR]

With the increase of the mining height, the operational condition of the hydraulic support is getting worse. Since the column and the balance jack are both regarded as rigid structural parts or springs with constant stiffness, this simplification cannot reflect the characteristics of each stage of the working process. To improve the analysis accuracy, a rigidity-variable impact dynamic simulation platform for hydraulic support with ultra-large mining height based on rigidity-flexibility coupling is constructed in this study. Firstly, stress states of hinge joints of the support when parallel surface loads, raising surface loads and down surface loads act on the upper beam were simulated, and critical loads of different hinge joints were recognized. Secondly, dangerous impact positions of support corresponding to different hinge joints were found. Finally, the overall influences of impact loads on stress state of the hydraulic support were summarized. Results show that under 6000 kN impact load, the maximum force variation coefficient at the hinge point of the shield beam of the support roof is 10.5, and it's the most dangerous hinged position. This study has certain guiding significance for the optimization of the support structure. [ABSTRACT FROM AUTHOR]

CaO-Al 2 O 3 -SiO 2 (CAS) glass ceramics were designed and prepared using a melt-quench approach. The coefficient of the thermal expansion (CTE) of the synthesized CAS (4.12 × 10−6 K−1) matched perfectly with that of the SiC ceramic (4.01 × 10−6 K−1). Thermal analysis of the CAS was conducted. Then the joining of the SiC ceramics by the CAS glass ceramics under various process parameters were conducted. The bonding temperature affects the fluidity of the CAS glass and the oxidation of the SiC substrate. The holding duration decides the infiltration of the CAS glass into the SiC substrate. The optimal bonding parameter is 1400 ℃/10 min and the corresponding highest shear strength of the SiC/CAS/SiC bonded joints in average was 56 MPa. Fracture observation was also conducted to help analyze the relationship between the interfacial microstructure and the joint strength. Finally, the formation mechanism of the SiC/CAS/SiC bonded joints was proposed. [ABSTRACT FROM AUTHOR]

This paper analyses high frequency MTS data to comprehensively evaluate the liquidity of the European sovereign bond markets before and during the European sovereign debt crisis for eleven countries. The Hill index, Generalized Hurst exponent and Dynamic Conditional Score are employed to evaluate the properties of the bid-ask spread. Sovereign bonds exhibit the stylized facts reported for a range of financial markets. The 1-min interval analysis indicates the level of bid-ask spread exhibits long-memory and the change in bid-ask spread experiences volatility clustering. In a dynamic setting, the volatility of bid-ask spread also exhibits long-memory in most European sovereign bond markets across all three maturities. Long-memory effects diminish (disappear) for 5-min (15-min) interval, and for short-term maturity (peripheral countries) is stronger than long-term maturity (core countries). Analysis of sub-periods indicates that long-memory process reached its peak during European sovereign debt crisis from May 2010 to December 2011. This analysis suggests that estimating long-memory parameters for high-frequency data could be a useful tool to monitor market stability. [ABSTRACT FROM AUTHOR]

We investigated the effects of astaxanthin supplementation and acute high intensity exercise on serum antioxidant capacity of human body, blood lactic acid and serum uric acid metabolism. Sixteen subjects were trained 28 days and were randomly divided into two groups: group A (experimental) and B (control). Four weeks later, all subjects underwent exercise on power bike. Immediately after exercise, the anti-oxidative capacity decreased in 2 groups, the lactic acid values of blood significantly increased, but compared with the group B the antioxidant capacity of the A group was significantly higher and blood lactate value lower. (1) Exercise can temporarily reduce the body's antioxidant capacity, increase blood lactic acid content, and slightly decrease blood uric acid content. (2) Astaxanthin intake can eliminate free radicals produced in the body, significantly reducing the increase in blood lactic acid and reducing blood uric acid value after acute high-intensity exercise. [ABSTRACT FROM AUTHOR]

Hot tearing mechanisms of a high-entropy alloy CoCrFeNi additively manufactured by selective laser melting have been investigated. Intergranular hot cracks are present regardless of various parameters used, suggesting poor laser-based printability for the alloy. Elemental segregation does not exist at the grain boundary that favours the hot cracking. We find that severe residual stress induced by the large grain size is the root cause for the intergranular cracking. The classic Rappaz-Drezet-Gremaud model is used to predict the characteristic depression pressure limit beyond which hot tearing will occur for the selective laser melting of metals and alloys. Unlabelled Image [ABSTRACT FROM AUTHOR]

The local structure of copper nanoparticles grown in organic solution by reducing Cu(II) hexafluoroacetylacetonate [Cu(hfac)2] was studied as-grown by the Cu K-edge x-ray absorption near-edge structure (XANES). Comparison of the experimental XANES spectra with reference materials indicated small copper clusters are formed by ligand-exchange with oleylamine and subsequent reducing by diphenylsilane. The multiple-scattering (MS) calculation for various model clusters consisting of 13-135 atoms suggests that small (13-19 atom) Cu clusters are stabilized without a large deformation. [ABSTRACT FROM AUTHOR]

We investigate magnetization reversal in a system of two Stoner particles with uniaxial anisotropies both subject to a static and antiparallel magnetic field, and taking into account their mutual dipolar interaction. We identify an interesting regime of stable synchronized magnetic dynamics where the two particles are implementing a single information bit. Here a modified Stoner-Wohlfarth limit occurs which results in a dramatically lower critical switching field Hc (including Hc=0) and also a substantially shorter reversal time. Our analytical results are verified by numerical simulations and offer new technological perspectives regarding devices for information storage and/or fast magnetic response. [ABSTRACT FROM AUTHOR]

Strong magnetic fields e.g., 10 T are now frequently used during materials preparation. In the present paper, a method of metal-ceramics graded materials preparation is proposed by applying a strong magnetic field with a high gradient. Experimental and theoretical analyses are performed to investigate the effect of the strong magnetic field on the migration and interaction behavior of diamagnetic oxide particles in a liquid metal. The migration of micrometer or sub-micrometer sized particles is clearly enhanced by the magnetic field gradient. After being treated by the strong magnetic field, a self-assembly structure of the particles is achieved. Various factors such as the magnetic dipole-dipole interaction and chain-chain interaction, are governing the particles assembly. The present results provide direct evidence that nonmetallic particles of micrometer size or less can be manipulated in a conductive melt by applying a strong magnetic field and as a consequence graded materials can be prepared. [ABSTRACT FROM AUTHOR]

With the help of first-principles GGA+U calculations, the origin of the deviation between the experimental and theoretical data for Cr2AlC was revealed. The structural, electrical and elastic properties of Cr2AlC were well described by considering the Cr 3d on-site Coulomb energy. The temperature effect on the bulk moduli of Cr2AlC was also studied within the quasiharmonic Debye model. Based on the present work, we propose that the electron correlation effects in Cr-containing MAX phases cannot be ignored. [ABSTRACT FROM AUTHOR]

We investigated the resonance and antiresonance effects in electronic transport through several-quantum-dot combinations by using the nonequilibrium Green’s function method. All distinctive quantum-dot (QD) arrangements with one to three QDs and with different architectures were studied systematically. The theoretical and numerical results show that a peak in the current-voltage spectrum can be attributed to the resonance effect, whereas a dip is due to the antiresonance effect. The results will help experimenters to better understand their electronic measurements. [ABSTRACT FROM AUTHOR]

The plastic deformation and fracture behavior of individual a- and c-domains of (001) oriented BaTiO3 single crystal are studied with nanoindentation and atomic force microscopy. Consistent with previous observations in rocksalt and perovskite crystals, square-shaped pileups directly surround the residual indents, and rosette arm patterns extend beyond these pileups. These features have been ascribed to dislocation activities on the {110}<110> slip systems induced by nanoindentations. We observed rosette screw arms only in c-domains, inside which 90° ac-domain switching is confirmed. We conclude that indentation-induced cracks on {110}90 planes most likely nucleate by dislocation pileups on two neighboring {110}45 planes, which create a sessile dislocation. Significantly shorter cracks in the c-domain under the same indentation load suggest a higher apparent toughness of the c-domain. However, we attribute the different crack lengths to the lower crack driving force resulting from indentation-induced plasticity in c-domains rather than an inherent difference in the crack growth resistance. [ABSTRACT FROM AUTHOR]

Molecular statics simulations combined with an embedded-atom method potential were performed to calculate the distributions of energy and bulk stresses in crystalline and amorphous Cu slabs and to examine the effect of surface relaxation on the distributions of energy and bulk stresses in the surface region. The results reveal that a release of energy and bulk stresses in the surface region occurs upon surface relaxation. The profile of energy release upon surface relaxation of a crystalline Cu slab exhibits oscillatory damping from the topmost layer to the interior layers, while that of an amorphous Cu slab exhibits monotonic decreasing. A great diversity of patterns was observed in the profiles of bulk stresses released upon surface relaxation, which may exhibit anisotropy according to the symmetry of the surface considered. Both the profiles of energy release and bulk stress release exhibit surface-orientation dependence. The present results may provide useful information to analyze different phenomena at Cu surfaces. [ABSTRACT FROM AUTHOR]

Polycrystalline BiMn2O5 and Bi0.9Ce0.1Mn2O5 have been prepared by a solid-state reaction. A crystalline structure study shows that all x-ray diffraction patterns can be indexed successfully in an orthorhombic phase. Substitution of Ce for Bi ions induced in the unit cell a slight distortion and enlargement. Magnetic and dielectric measurements all reveal that Ce substitution induces great effects: BiMn2O5 is in the antiferromagnetic (AFM) phase with a Néel transition temperature at about 42 K, whereas Bi0.9Ce0.1Mn2O5 is in the ferromagnetic (FM) phase with a Curie temperature at about 46 K. The permittivity of Bi0.9Ce0.1Mn2O5 is much higher than that of BiMn2O5, and two dielectric relaxation peaks have been observed in the former, instead of one dielectric loss peak as observed in BiMn2O5. The valent state of Ce ions has been analyzed mainly as tetravalent by the core-level spectrum of Ce 3d from x-ray photoemission spectroscopy. The possible mechanisms of the magnetic transition from AFM to FM and the peculiar dielectric relaxation peaks induced by Ce substitution have been discussed in detail. [ABSTRACT FROM AUTHOR]

Neodymium-doped GeO2/γ-glycidoxypropyltrimethoxysilane hybrid planar waveguide films were prepared by a low-temperature sol-gel technique from an organic-inorganic hybrid system for photonic applications. Optical properties such as refractive index, thickness, propagation modes, and attenuation coefficient of the hybrid planar waveguides were investigated by using a prism coupling technique. An intense room-temperature yellow-to-violet up-conversion emission at 397 nm (4D3/2→4I13/2) was measured from the hybrid planar waveguide film heated at a low temperature of 100 °C upon excitation with a xenon lamp at the wavelength of 580 nm. In addition to this intense violet emission, a relatively weak ultraviolet emission at 376 nm and a blue emission at 468 nm were also observed. The mechanism of the up-conversion emission is proposed, and they indicate that the excited-state absorption process originating from the long-lived 4F3/2 excited state should be responsible for the up-conversion process. [ABSTRACT FROM AUTHOR]

We investigated the field emission properties and resistivity of polymer-based carbon films prepared from poly ethyl-co-phenyl carbyne polymer precursors after treatment at different temperatures. As the heat-treatment temperature increased from 40 to 1200 °C, the emission threshold field decreased from 12.4 to 2.1 V/μm, the emission current density increased from 0.1 to 6.1 mA/cm2, and the film resistivity decreased from 108 to 102 Ω cm. The structural changes of the polymer films during the heat-treatment process were analyzed by Raman spectroscopy and atomic force microscopy. Raman analysis of these polymer-based carbon films suggests that the hydrogen content decreased while the sp2 carbon phase increased as the heat-treatment temperature increased. The dependence of the field emission properties of the polymer-based carbon films on the film structures (such as sp3, sp2 phases), film surface morphology and film resistivity is discussed. The enhancement of field emission from polymer-based carbon films was related to the increase of sp2/sp3 ratio, film conductivity, and surface roughness with the heat-treatment temperature. [ABSTRACT FROM AUTHOR]

The effect of ion implantation including ion species (N[sub 2][sup +] and C[sub 3]H[sub 8][sup +]) and the fluences (1×10[sup 14]–5×10[sup 15] ions/cm[sup 2]) on the surface energy of ultrahigh molecular weight polyethylene (UHMWPE) were investigated. The total surface energy increases significantly after implanting with the fluence of 1×10[sup 14] ions/cm[sup 2] regardless of ion species, then, the total surface energy slightly increases for N[sub 2][sup +] implanted UHMWPE and decreases slightly for C[sub 3]H[sub 8][sup +] implanted UHMWPE with a further increase of fluence. The structural changes of UHMWPE with different fluence for different ion species are very similar. The linear chains of UHMWPE are damaged and cross linking is generated after implantation. As the fluence increases, the polymer surface becomes more disordered, and the surface becomes hydrogenated amorphous carbon when the fluence exceeds 1×10[sup 15] ions/cm[sup 2]. The surface roughness increases with the increase of the fluence regardless of ion implantation species. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The magnetic properties of Nd[sub 60-x]Y[sub x]Fe[sub 30]Al[sub 10] (x = 0, 10, 30) melt-spun ribbons were studied. The ribbons contain two amorphous magnetic phases characterized by their Curie temperature T[sub C1] and T[sub C2]. The Y atoms may be unevenly distributed in the two magnetic phases. The Y atoms prefer to substitute Nd in the low T[sub C1] phase. Thermo-history effects are found in the thermomagnetic curves for field-cooled and zero-field-cooled samples. The bifurcation temperature T[sub b] decreases with Y addition, suggesting a decrease of the anisotropy energy and the coercivity. The room-temperature coercivity and remanence ratio also strongly decrease with Y addition. The apparent coercivity μ[sub 0]H[sub C] for x = 0 first increases with decreasing temperature, reaching a maximum at about 60 K, near the Curie temperature of the T[sub C1] phase, then strongly decreases in the two-magnetic phase region. The coercivity mechanism is assumed as domain-wall pinning effect. [ABSTRACT FROM AUTHOR]

Presents a study which deposited diamond-like carbon films by a plasma chemical vapor deposition system. Properties of the carbon films; Results; Conclusions.

Erbium doped gallium nitride (Er:GaN) bulk crystals have emerged as a promising optical gain material for high energy lasers (HELs) operating at the 1.5 μm "retina-safe" spectral region. Among the many designs of HEL gain medium, the core-cladding planar waveguide (PWG) structure is highly desired due to its abilities to provide excellent optical confinement and heat dissipation. We report the realization of a GaN/Er:GaN/GaN core-cladding PWG structure synthesized by hydride vapor phase epitaxy and processed by mechanical and chemical-mechanical polishing. An Er doping concentration of [Er] = 3 × 1019 atoms/cm3 has been attained in the core layer, as confirmed by secondary ion mass spectrometry measurements. A strong 1.54 μm emission line was detected from the structure under 980 nm resonant excitation. It was shown that these PWGs can achieve a 96% optical confinement in the Er:GaN core layer having a thickness of 50 μm and [Er] = 3 × 1019 atoms/cm3. This work represents an important step toward the realization of practical Er:GaN gain medium for retina-safe HEL applications. [ABSTRACT FROM AUTHOR]

Abstract The traditional potential-flow-based hydroelasticity computation is unable to directly simulate the violent free surface deformation and slamming, and has a lack of mutual interactions between rigid-body and flexible motion parts. In this paper, the modified MPS (Moving Particle Semi-implicit) and modal superposition methods are used for the time-domain hydroelasticity computation of cylindrical shell and non-uniform beam structures involving violent free surface deformation and slamming. The improved modal superposition technique is revisited and extended to derive the time-domain governing equations for flexible shell and non-uniform beam motions, which couples rigid-body and flexible modes and considers the mutual interaction between them. The modified MPS method developed by the authors previously is first validated by the rigid cylinder water problem, and then the flexible cylindrical shell water entry and ship hull structure slamming are simulated. Relatively good agreement has been obtained between current results and the available numerical and experimental data, which shows the feasibility of the proposed model for the hydroelasticity computation involving violent free surface deformation. [ABSTRACT FROM AUTHOR]