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A hydroelastic analysis method for flexible ships with forward speed is developed based on the beam-connected-discrete-modules (BCDM) approach. In this method, the flexible ship is first discretized into multiple rigid modules connected by a hull girder, thereby establishing the hydroelastic analysis model. The time-domain Rankine source method, which incorporates steady flow through the double body flow model, is employed to calculate the hydrodynamic forces acting on the multi-module system. The subsequent application of Fourier transformation facilitates the conversion of these forces into the frequency domain, where they are coupled with the structural stiffness of the hull girder to formulate the hydroelastic equations for advancing ships. Additionally, the time-domain hydroelastic equation is derived based on Cummins' equation. The validity of the proposed method is conducted by comparing the zero-speed hydroelastic responses and the motions of advancing ships with the published data and numerical results from commercial software. Furthermore, the global responses of both flexible and rigid ships under varying forward speed conditions are thoroughly investigated. The results demonstrate that the flexible deformation plays a crucial role in the global responses of advancing ships, and hydrodynamic forces associated with forward speed have significant contribution to the hydroelastic responses. • A hydroelastic method for ships with forward speed avoids generalized modes. • The time-domain Rankine source method is employed to calculate multi-module forces. • Global responses of flexible and rigid ships at varying speeds are investigated. • Independent wave input allows wave–current interaction under inhomogeneous waves. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive approach for the linearized frequency-domain analysis of hydrodynamic loading and structural responses on a deformable body. The structural and hydrodynamic analyses are integrated by employing the mode superposition method. Commencing with an eigenvalue analysis on the structural model, the shapes of selected modes, mass, and structural stiffness matrices are extracted as input to the subsequent hydrodynamic analysis, where the global response is solved in the modal space. The resulting hydrodynamic and inertial loads are then transferred to the same finite element model for stress assessment. To exemplify the proposed methodology, a bottom-fixed flexible cylindrical monopile and a long box-shaped barge model are investigated. For the barge model, the sectional loads are obtained from the integral of stresses in the cuts along the structure model, which are found to be consistent with those from the hydrodynamic analysis, demonstrating the consistency of the entire workflow. In particular, this paper introduces a straightforward formulation for evaluating the generalized restoring matrices, eliminating the need for spatial derivatives of the mode shape function and thereby significantly reducing numerical uncertainties in using the flexible modes derived from finite element model for hydrodynamic analysis. • An integrated hydrodynamic-structural analysis workflow is proposed to account for the deformable motions of large volume floating structures. • Mode shapes FE model is taken as input to hydrodynamic analysis, with the resulting loads applied to the same model for stress evaluation. • Straightforward formulations proposed for restoring matrices, eliminating the need to operate with the spatial derivatives. • Mode superposition approach is validated against discrete module method to evaluate sectional loads and stresses for a flexible barge model. [ABSTRACT FROM AUTHOR]

• Biform games can coordinate supply chains with competition and cooperation relation. • Carbon complementary is a beneficial way to organize the internal carbon trading. • The pareto improvement can be achieved under hybrid carbon trading schemes. • We incorporate the Minimax and Maximin principle and Shapley value into biform game. Cap-and-trade, Certified Emission Reductions (CERs) and Renewable Energy Consumption Obligation (RECO) are three regulatory instruments used by governments to decarbonize supply chains. Integrating these mechanisms creates a Carbon Complementary Supply Chain (CCSC), in which traditional energy manufacturers (TMs) with high emissions can offset their carbon footprint by trading CERs with renewable energy manufacturers (RMs) who develop the CER projects, and compete with RMs. In the downstream, retailers are incentivized to procure more renewable energy products to avoid RECO penalties. Given that all the CCSC members tend to cooperatively invest in the CER project, this paper proposes a novel biform game-based coordination mechanism combining noncooperative and cooperative games to promote CCSC's synergy. The findings show that this mechanism can induce CCSC members to cooperate, achieving Pareto improvement in social welfare, economic performance, and individual profits under specific regulatory intensity thresholds compared to the noncooperative scenario. Our findings contribute to the ongoing debate on the role of carbon regulations in enhancing supply chain performance by providing insights into the contractual relationships among supply chain members and the economic forces at play. [ABSTRACT FROM AUTHOR]

In this study, a two-step stress analysis method to incorporate the global hydroelasticity and local bending effect is developed in the frequency domain. In the first step, the continuous structure is discretized into several rigid modules connected by elastic beams to evaluate global hydroelastic responses, known as the beam-connected-discrete-modules (BCDM) hydroelasticity method. In the second step, the hydrodynamic and hydrostatic pressure as well as inertia forces in step one are mapped on an entire finite element model to estimate the stresses by a quasi-static method. In this method, the boundary value problem solved in the generalized mode is replaced by multi-body hydrodynamics which has been extensively studied. The application of the proposed method is first verified against the results from modal-based method and published experimental data. Then, the effect of local bending and global flexible deformation on the stress is investigated through an intentionally flexible barge with an open-cross section. The results show that the local bending leads to an increase in the stress for some non-resonant frequencies. The global flexible deformation mode contributes significantly to the stress when the resonance vibration is excited, which is caused by the associated inertia forces. • A two-step stress analysis method to incorporate the global hydroelasticity and local bending effect is developed in the frequency domain. • Based on the proposed method, the multi-body hydrodynamics can be used to conduct stress analysis of flexible structures. • The local bending leads to an increase in the stress for some non-resonant frequencies and change the stress distribution. • The effect and mechanism of global flexibility on the stresses are conducted through the comparison of three different load models. [ABSTRACT FROM AUTHOR]

This paper presents a frequency-domain method for the stress analysis of flexible floating structures exposed to a spatially inhomogeneous wave field. A hydroelastic model is developed for the continuous structure, wherein discrete rigid modules are connected by elastic beams with equivalent stiffness. The inhomogeneous wave field is divided into wave regions characterized by constant wave parameters. By assigning distinct wave parameters to modules based on their respective positions, the global hydroelastic equation is established to capture the wave inhomogeneity. To compute the stress, external loads in the hydroelastic equation, comprising hydrodynamic and hydrostatic restoring pressures, as well as inertia forces, are mapped onto the finite element model of the continuous structure, enabling stress calculation by the quasi-static method. Variations in wave directions and heights along the longitudinal direction of the structure are introduced with the aim of exploring the effect of the wave inhomogeneity on the stress. A deliberately flexible barge is constructed to evaluate the stress resulting from global structural vibrations. The results demonstrate a significant contribution of wave inhomogeneity to the stress, particularly during structural resonance frequencies. Moreover, an exclusive phenomenon is observed whereby the inhomogeneous wave field induces stress due to anti-symmetric vibrations under beam sea conditions. • A frequency-domain stress analysis method for flexible structures in inhomogeneous waves is developed. • The wave inhomogeneity makes a significant contribution to the stress, particularly during structural resonance frequencies. • An exclusive phenomenon is observed whereby the inhomogeneous wave field induces stress due to anti-symmetric vibrations under beam sea conditions. [ABSTRACT FROM AUTHOR]

• A mixed integer program model for urban subway peak-easing is proposed. • Peak-staggering commuting has been designed for resuscitation under the COVID-19. • A balance has been struck between the spread of the epidemic and work resumption. Subways play an important role in public transportation to and from work. In the traditional working system, the commuting time is often arranged at fixed time nodes, which directly leads to the gathering of "morning peak" and "evening peak" in the subway. Under the COVID-19 pandemic, this congestion is exacerbating the spread of the novel coronavirus. Several countries have resorted to the strategy of stopping production to curb the risk of the spread of the epidemic seriously affecting citizens' living needs and hindering economic operation. Therefore, orderly resumption of work and production without increasing the risk of the spread of the epidemic has become an urgent problem to be solved. To this end, we propose a mixed integer programming model that takes into account both the number of travelers and the efficiency of epidemic prevention and control. Under the condition that the working hours remain the same, it can adjust the working days and commuting time flexibly to realize orderly off-peak travel of the workers who return to work. Through independent design of travel time and reasonable control of the number of passengers, the model relaxes the limitation of the number of subway commuters and reduces the probability of cross-travel between different companies. We also take the data of Beijing subway operation and apply it to the solution of our model as an example. The example analysis results show that our model can realize the optimal travel scheme design of returning to work at the same time node and avoiding the risk of cross infection among enterprises under different epidemic prevention and control levels. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dispersant BOBD derived from bio-oil has been synthesized for CWS. • The route of synthesized BOBD is simple and environmentally friendly. • The maximum coal contents of CWS with BOBD may reach about 72 wt%. • BOBD shows an excellent dispersibility comparing to SL and PSS in CWS. • BOBD has the lowest surface tension of 47.71 mN/m−1 relative to SL and PSS. • The contact angle of BOBD on the coal surface decrease by 24% comparing to SL and PSS. With pyrolytic bio-oil as raw material, an efficient bio-oil-based dispersant (BOBD) applied to coal water slurry (CWS) has been synthesized successfully by grafting polymerization of the organic fractions from the bio-oil and acrylic acid (AA) in the mild condition. As a comparison, two commercial dispersants, namely poly (styrene sulfonic acid) sodium (PSS) and sodium lignosulfonate (SL) were employed. The structures and properties of the synthesized BOBD were characterized by using FTIR, 1H NMR, GC/MS, GPC, zeta potential, contact angle, and surface tension. The results showed the molecular weight of the BOBD was concentrated at 832 g/mol and 1954 g/mol. The surface tension and contact angle of BOBD aqueous solution were 47.71 mN/m−1 and 60.8° respectively. The zeta potential of the suspension prepared from BOBD-water-coal was −67.1 mV. Using BOBD as a dispersant, the apparent viscosity of CWS loading 66 wt% coal dropped to 288 mPa·s at 0.3 wt% BOBD, and the maximum coal content reached 72 wt%. BOBD exhibited better viscosity reduction and stability enhancement capabilities than PSS and SL. The excellent dispersion performance of BOBD was due to the large electrostatic repulsion and steric hindrance derived from the grafted acrylic polymer, which effectively dispersed the coal particles uniformly. The rheological behavior of CWS with BOBD belonged to pseudoplastic fluid. The synthesized BOBD not only had an excellent dispersion performance but also could overcome the shortcomings of secondary pollution caused by PSS and SL containing element sulfur as dispersants in combustion. In addition, the synthetic route possessed simple, environmentally friendly and sustainable characteristics. The research opened up a new way for the utilization of bio-oil. [ABSTRACT FROM AUTHOR]

Due to the complexity of the second-order boundary value problem (BVP) considered in the generalized mode, the second-order hydroelasticity analysis is still challenging. Based on the beam-connected-discrete-modules (BCDM) method, this study proposes a second-order hydroelastic method for floating structures in the frequency domain. In this method, the second-order BVP for flexible structures is replaced by multi-rigid-body hydrodynamics which has been extensively studied. The first-order hydroelastic responses of a hemisphere and the second-order sum-frequency forces using the proposed method are verified against the results obtained by general commercial software and published data. Then, the effect of flexural rigidity on the second-order hydrodynamic forces and responses is investigated. The results show that the second-order forces are dominated by the first-order springing, especially for the quadratic product force component. Additionally, due to the discrete property of the BCDM method for hydrodynamics, the present method can be directly extended to inhomogeneous wave conditions. • A second-order hydroelasticity method for a flexible body is developed in the frequency domain. • The method is demonstrated by a case study on a freely-floating elastic hemisphere. • Linear springing induces considerable second-order forces, especially for the quadratic product force term. • The quadratic product force for flexible structures contributes appreciably in high-frequency regions. [ABSTRACT FROM AUTHOR]

In this study, a second-order hydroelastic analysis method for moored flexible floating structures under spatially inhomogeneous, long-crested waves is developed, based on the beam-connected-discrete-modules (BCDM) hydroelastic method. The continuous structure is first discretized into rigid modules connected by elastic beams to evaluate the first-order hydroelastic responses. The inhomogeneous wave field is spatially discretized by different isolated homogeneous waves. Based on the first-order motions, the mean drift force on each module is obtained in the frequency-domain. According to the discrete inhomogeneous wave field, the second-order slowly-varying wave drift forces by Newman's approximation with the drift forces are calculated using the corresponding wave spectra. Finally, the second-order hydroelastic equation in inhomogeneous waves is established in the time-domain using Cummins' equation. The mean drift force of flexible structures and the nonlinear time histories of motions under homogeneous waves using the proposed method are verified against the results obtained by general commercial software. Then, a limited case study using the proposed method is conducted by a flexible barge and an inhomogeneous wave condition, both of which are exaggerated. The results show that slowly-varying drift forces dominate the horizontal displacements and mooring forces, and the spatial inhomogeneity of waves has a significant effect on the second-order hydroelastic responses, especially in beam seas. • A second-order hydroelasticity method for floating structures in inhomogeneous waves is developed. • The method is demonstrated by a case study on a moored flexible barge. • Both inhomogeneous wave and second-order wave forces' effects on the hydroelastic responses are investigated. • The wave inhomogeneity has a significant influence on the second-order hydroelastic responses. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence of lens opacities in the elderly Chinese population in an urban and a rural region of Beijing. Design: Population-based cross-sectional study. Participants: The study included 4439 subjects of 5324 subjects invited to participate (response rate, 83.4%). The subjects were divided into a rural part (1973 subjects [44.4%]) and an urban part (2466 subjects [55.6%]). The study was limited to participants age 40 and older, and the mean age was 56.2±10.6 years (range, 40–101 years). Methods: Nuclear, cortical, and posterior subcapsular lens opacities were assessed based on standardized slit-lamp photographs of the lens using a modification of the grading score of the Age-related Eye Disease Study (AREDS). Main Outcome Measures: Grading score of the AREDS. Results: Lens data were provided for 4378 subjects (98.6%) of 4439 persons examined, which consisted of 8724 eyes. Prevalence of any cataract surgery was 1.3% (95% confidence interval [CI]: 1.0–1.7), which was statistically independent of gender (P = 0.51; odds ratio [OR]: 0.86; 95% CI: 1.00–1.34), rural area versus urban region (P = 0.25), and level of education (P = 0.84). Prevalence of any nuclear lens opacity was 82.0% (95% CI: 80.8–83.2); prevalence of any cortical lens opacity was 10.3% (95% CI: 9.4–11.3); and prevalence of any posterior subcapsular opacity was 4.3% (95% CI: 3.7–4.9). If grade 2 of nuclear lens opacity was considered to be normal, prevalence of nuclear cataract was 50.3% (95% CI: 48.8–51.8), and the overall prevalence of any cataract was 53.1% (95% CI: 51.6–54.6), increasing from 6.5% (95% CI: 5.2–7.8) in those subjects 40 to 49 years of age to 52.3% (95% CI: 47.4–55.3) in those who were 50 to 59 years of age, and to 97.8% (95% CI: 96.4–99.2) in those 70 years and older (P<0.001). Frequencies of any cortical cataract and any subcapsular posterior cataract were 10.3% (95% CI: 9.4–11.3) and 4.3% (95% CI: 3.7–4.9), respectively. Conclusions: Cataracts are common among adult Chinese residents in Beijing, with age as the most important associated factor. In view of the relatively low rate of cataract surgery performed so far, one may expect a marked increase in the number of cataract surgeries to meet the visual needs of the growing elderly population in China. [Copyright &y& Elsevier]

Black-White disparities in cardiac care may be related to physician referral network segregation. We developed and tested new geographic physician network segregation measures. We used Medicare claims to identify Black and White Medicare heart disease patients and map physician networks for 169 hospital referral regions (HRRs) with over 1000 Black patients. We constructed two network segregation indexes ranging from 0 (integration) to 100 (total segregation): Dissimilarity (the unevenness of Black and White patient distribution across physicians [Dn]) and Absolute Clustering (the propensity of Black patients' physicians to have closer ties with each other than with other physicians [ACLn]). We employed conditional logit models to estimate the probability of using the best (lowest mortality) geographically available hospital for Black and White patients undergoing coronary artery bypass grafting (CABG) surgery in 126 markets with sufficient sample size at increasing levels of network segregation and for low vs. high HRR Black patient population. Physician network segregation was lower than residential segregation (Dissimilarity 21.9 vs. 48.7, and Absolute Clustering 4.8 vs. 32.4) and positively correlated with residential segregation (p <.001). Network segregation effects differed by race and HRR Black patient population. For White patients, higher network segregation was associated with a higher probability of using the best available hospitals in HRRs with few black patients but unchanged (ACLn) or lower (Dn) probability of best hospital use in HRRs with many Black patients. For Black patients, higher network segregation was not associated with a substantial change in the probability of best hospital use regardless of the HRR Black patient population size. Measuring physician network segregation is feasible and associated with nuanced effects on Black-White differences in high-quality hospital use for heart disease. Further work is needed to understand underlying mechanisms and potential uses in health equity policy. • Novel methods measure physician network segregation in healthcare markets. • Network segregation is well correlated with residential segregation. • Its relationship with best hospital use for open heart surgery varies by race. • Network segregation may improve White patients' high-quality hospital use. • Network segregation does not influence Black patients' high-quality hospital use. [ABSTRACT FROM AUTHOR]

The pontoon-supported floating bridge is an alternative concept for crossing a fjord with a width of up to 5 km. Due to the huge span, the first two natural periods of the bridge are more than 60 s, indicating that the corresponding modes can be excited by slowly-varying drift forces on the pontoons. A simplified approach for determining the drift forces is to assume that the pontoons are independent of the floating bridge, i.e., fixed or freely floating. However, the first-order motions of the pontoons, which are restricted by the deformation of the floating bridge, have a significant effect on the drift forces. To evaluate the uncertainties implied by the simplification of drift forces, in this study, a second-order beam-connected-discrete-modules (BCDM) hydroelastic method is adopted to assess the effect of different drift force models on the floating bridge. In this method, the first-order response amplitude operators (RAOs) of bridge-restricted pontoons are first solved in the frequency-domain. Based on the RAOs, the mean drift forces for each pontoon are then determined by using potential theory. Considering the spatial inhomogeneity of the wave field, the time series of the first- and second-order wave forces are generated by using the linear transfer functions and Newman's approximation, respectively. Then, the method is applied to investigate the hydroelastic responses of a straight side-anchored floating bridge for the crossing site of Bjørnafjord. The results show that the horizontal displacement is very sensitive to the different force models implied by various pontoon boundary conditions, i.e., free, fixed, and bridge-restricted. The drift forces on the bridge-restricted pontoons are approximately 10%–20% larger than those for the fixed pontoons. Moreover, wave inhomogeneity results in increased vertical displacements and weak axis bending moments. • A second-order hydroelastic method for floating bridges in inhomogeneous waves is developed. • The horizontal displacement is sensitive to different drift force models. • The effect of wave inhomogeneity is various for different response variables. • Wave short-crestedness should be considered for very large floating bridges. [ABSTRACT FROM AUTHOR]

Objectives The primary objective of this systematic survey was to examine the percentage of studies in which there was agreement in the reporting of the primary outcome between the currently updated version of the clinical trial registry and the published paper. We also investigated the factors associated with agreement in reporting of the primary outcome. Methods We searched PubMed for all randomized control trials (RCT)s published in 2012–2015 in the top five general medicine journals (based on the 2014 impact factor). Two hundred abstracts (50 from each year) were randomly selected for data extraction. Agreement in reporting of 11 key study conduct items (e.g., sample size) and study characteristics (e.g., funding, number of sites) were extracted by two independent reviewers. Analysis Descriptive analyses were conducted to determine the proportion of studies on which there was agreement in reporting of key study conduct items. Generalized estimating equations were used to explore factors associated with agreement in reporting of the primary outcome. Results Of the 200 included studies, 87% had agreement in reporting of the primary outcome. After adjusting for other covariates, having greater than 50 sites was associated with an increased likelihood of agreement in reporting of the primary outcome (odds ratio = 7.1, 95% confidence interval = 1.39, 36.27, p = 0.018). Conclusions We identified substantive disagreement in reporting between publications and current clinical trial registry, which were associated with several study characteristics. Further measures are needed to improve reporting given the potential threats to the quality and integrity of scientific research. [ABSTRACT FROM AUTHOR]

Abstract: A series of bulk polycrystalline (La1−x Sm x )2/3Sr1/3MnO3 () samples were prepared by traditional solid-phase reaction method. Their structures, magnetoresistances and magnetostrictions were studied. The experimental results indicate that with the increase of the Sm content , the average ionic radius of the A site and the Curie temperature of the samples decrease, the maximum of the zero-field resistivity at and corresponding magnetoresistance increase. The magnetostriction measurement shows that the anisotropic magnetostriction coefficient are nearly zero, while the volume magnetostriction coefficients are negative for the and 0.7 samples, which implies that the volumes of the samples are contracted at the temperature just below the Curie temperature, and no saturation occurred even under 7 T strong magnetic field. For the sample, the maximum of is −550×10−6 in the magnetic field of 7 T at 210 K. These experimental results can be interpreted by the viewpoint of phase separation due to the substitution of Sm3+ with smaller ionic radius for La3+ with larger ionic radius in the samples. [Copyright &y& Elsevier]

Abstract: Polycrystalline Ag x (Fe3O4)1−x films (, 0.1, 0.2 and 0.3) have been prepared by the sol–gel method in combination of the spin-coating technique with a precursor solution containing polyvinyl alcohol (PVA) on fused quartz substrates. XRD analysis and SEM images indicate that the Fe3O4 grains are nearly spherical single-domain particles. The coercivities of the films are about 290 Oe for and 360 Oe for , respectively, which are nearly the same as the magnetocrystalline anisotropic effective field of Fe3O4. At 300 K, the film has a maximal magnetoresistance of −8.7% at a magnetic field of 50 kOe and −3.5% at 8.8 kOe, while the pure Fe3O4 film is only −2.2% at 8.8 kOe. This enhancement of the MR can be attributed to the contribution from the spin-dependent scattering at the Ag–Fe3O4 interfaces as well as the spin-polarized tunneling at boundaries of Fe3O4 grains of the spin-polarized electrons. In addition, different MR behaviors for Ag-added Fe3O4 bulk polycrystalline samples and polycrystalline films are discussed. [Copyright &y& Elsevier]

Abstract: A series of bulk polycrystalline Ag-added Fe3O4 with a nominal composition, (Fe3O4)1−x Ag x (x is molar fraction) with x=0, 0.1, 0.2, 0.3, 0.4, and 0.5 have been prepared by conventional solid-state reaction. X-ray diffraction patterns show that the pure Fe3O4 sample (x=0) has a single-phase inverse spinel structure, while the Ag-added samples are two-phase composites consisting of a ferrimagnetic Fe3O4 phase and a non-magnetic metal Ag phase. The bright-field transmission electron microscopy images exhibit that the samples are typical granular solids with a porosity of about 22%. The addition of Ag slightly increases the average grain size of the Fe3O4 phase and significantly enhances the MR effect of bulk polycrystalline Fe3O4 samples. Of all the samples the x=0.3 sample has a maximal MR of −5.1% at 300K in a magnetic field of 1T, and −6.8% in 5T, which are approximately three times greater than the corresponding MR values (−1.8% at 1T and −2.4% at 5T) of the Fe3O4 sample. This enhancement of the MR can be attributed to the combination effect from the spin-dependent scattering at the interfaces between the Fe3O4 grains and the Ag granules and the spin-polarized tunneling at grain boundaries of Fe3O4 phase of the spin-polarized electrons. [Copyright &y& Elsevier]

The exploitation of cost-effective bifunctional seawater electrocatalyst is an attractive technology to generate hydrogen fuel. Sustainable seawater splitting requires catalysts with robust hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity as well as superior chloride corrosion resistance in the salty electrolyte. Here we designed a sandwich-like Ni 3 S 2 -MoS 2 -Ni 3 S 2 @Ni foam (NMN-NF) catalyst on the surface of Ni foam by stacking Ni 3 S 2 coatings as top and bottom protective layers (chloride anti-corrosion), and MoS 2 as an interlayer to trigger both HER and OER in salty water. The unique sandwich structure endowed NMN-NF catalysts with excellent bifunctional catalytic activity and long-term durability in alkaline seawater electrolytes. Taking advantage of the synergistic effect between MoS 2 and Ni 3 S 2 , NMN-NF delivered a current density of 100 mA/cm2 at a low voltage of 1.82 V under operating over 100 h in alkaline seawater, allowing them a promising catalyst towards practical application for efficient seawater splitting. [ABSTRACT FROM AUTHOR]