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As-cast beryllium-aluminum (Be-Al) alloy exhibits a coarse microstructure with pore defects due to a large solidification interval, greatly limiting its mechanical properties. In this research, the relationship between laser surface remelting process and microstructure and hardness of as-cast Be-Al-Sc-Zr alloy was established. The experimental results demonstrated that a pore-free refined microstructure of remelted layer was obtained by controlling the parameter of effective laser energy input. The microstructure of as-cast Be-Al-Sc-Zr alloy consisted of equiaxed grains with Al phase forming a continuous frame wrapping Be phase, which was significantly refined in the remelted zone (from 25 μm to 2 μm). The Vickers hardness in the remelted zone (approximately 210 HV) was approximately 3 times that of as-cast Be-Al-Sc-Zr alloy. Analysis of the Vickers hardness and the Be phase size showed a good agreement with a Hall-Petch equation. In addition, transmission electron microscopy (TEM), auger electron spectroscopy (AES) and X-ray diffraction (XRD) analysis evidenced that Sc and Zr elements formed a single blocky phase Be13(Scx,Zr1-x), which was also greatly refined from 8 μm to 1.5 μm in the remelted zone. The results obtained in this study indicate that the laser surface remelting allowed refining the microstructure and further strengthening the Vickers hardness of Be-Al-Sc-Zr alloy.

Draw-down time for a stochastic process is the first passage time of a draw-down level that depends on the previous maximum of the process. In this paper we study the draw-down-related Parisian ruin problem for spectrally negative Lévy risk processes. Intuitively, a draw-down Parisian ruin occurs when the surplus process has continuously stayed below the dynamic draw-down level for a fixed amount of time. We introduce the draw-down Parisian ruin time and solve the corresponding two-sided exit problems via excursion theory. We also find an expression for the potential measure for the process killed at the draw-down Parisian time. As applications, we obtain new results for spectrally negative Lévy risk processes with dividend barrier and with Parisian ruin.

In this paper we consider two cases of optimal implementation delay of taxation with trade-off under spectrally negative Levy insurance risk processes. In the first case, we assume that the insurance company starts to pay tax only when its surplus level reaches a certain level, and at the termination time of the business there is a terminal value incurred to the company. A method is developed to determine the optimal starting-tax surplus level at which the total expected discounted value of all tax payments up to the termination time plus the discounted terminal value is maximized. In the second case, the company still pays tax subject to a starting-tax surplus level, but with capital injections to prevent bankruptcy. The total expected discounted value of tax payments minus the total discounted capital injection costs is maximized to determine the optimal starting-tax surplus level. Numerical examples are given at the end to illustrate the existence of positive optimal starting-tax surplus levels for both cases considered in this paper.

Correntropy has recently attracted great attention because of its robustness to non-Gaussian noise. Inspired by this robustness property, a spline adaptive filtering algorithm based on the maximum correntropy criterion (SAF-MCC) has been proposed. However, the steady-state convergence performance of the SAF-MCC has not been studied. This brief presents a steady-state performance analysis of the SAF-MCC for Gaussian and non-Gaussian noise. We derive and discuss the theoretical excess mean square error (EMSE) under these cases. Monte Carlo simulations are presented to corroborate the theoretical performance analysis results developed in this brief. Refereed/Peer-reviewed

The first isolable silylene-germylene complex 5 was assembled by a salt metathesis reaction between the germylene anion 3 and the N-heterocyclic chlorosilylene 4, and structurally characterized. The central structure of 5 demonstrates a remarkable gauche-bent geometry with the silylene and germylene units, which are interconnected by a Si-Ge bond with a length of 2.4498(9) A. This value is not only perceptibly longer than the distances known in doubly bonded germasilenes, and also slightly longer than those in germylsilanes. The DFT calculations on 5 confirmed a nearly nonpolar SiI -GeI single-bond nature and its bonding orbital, as well as the aromaticity of the C3 NGe-rings in 3 and 5. The latter increases the molecular stability of 3 and 5, and makes the preparation of silylene-germylene complex 5 a reality.

This paper considers an insurance surplus process modeled by a spectrally negative Levy process. Instead of the time of ruin in the traditional setting, we apply the time of drawdown as the risk indicator in this paper. We study the joint distribution of the time of drawdown, the running maximum at drawdown, the last minimum before drawdown, the surplus before drawdown and the surplus at drawdown (may not be deficit in this case), which generalizes the known results on the classical expected discounted penalty function in Gerber and Shiu (1998). The results have semi-explicit expressions in terms of the q -scale functions and the Levy measure associated with the Levy process. As applications, the obtained result is applied to recover results in the literature and to obtain new results for the Gerber–Shiu function at ruin for risk processes embedded with a loss-carry-forward taxation system or a barrier dividend strategy. Moreover, numerical examples are provided to illustrate the results.

In this paper, we propose a modified version of exponential cost function to improve the stability of adaptive algorithm, where the recursive algorithm is based on the Dawson function. The second-order Volterra (SOV) filter is incorporated into the proposed recursive algorithm, resulting the SOV-ExRLS algorithm, to achieve the improved performance in both $$\alpha $$-stable and Gaussian environments. Moreover, the mean and mean-square behavior of the SOV-ExRLS algorithm is analyzed. In particular, the proposed cExRLS-IDLMS method is convexly combined with the functional link artificial neural network filter to flexibly model the chaotic memristor system. Simulation studies verify the analytical findings and reveal enhanced identification performance of the proposed algorithms over the existing nonlinear algorithms.

Low temperature scanning tunneling microscopy (LT-STM) has been applied to investigate the adsorption of acetylene (C2H2) on the rutile TiO2(110) surface at 77 K. Through in situ exposing and ex situ annealing experiments we unambiguously demonstrate that C2H2 molecules adsorb weakly on top of the Ti5c ions. Moreover, our data clearly reveal that the oxygen vacancy (Ov) cannot directly adsorb C2H2 molecules but can activate its next-nearest Ti5c ions which register as a binding site for C2H2 molecules with enhanced stability. Further increasing the C2H2 coverage leads to the stepwise formation of c-(4 × 2) and c-(2 × 2) ordered structures before final saturation at around 0.68 monolayer. The saturated film is characterized by dominating C2H2 dimers and other minority linear clusters whose intermolecular distances are slightly larger than the intervals between Ti5c ions yet significantly shorter than the C2H2 dimers in the gas phase. We propose that such clustered C2H2 may serve as potential precursors for the polymerization reactions on metal oxide surfaces.

In this paper, we study a spectrally negative Levy process that is reflected at its drawdown level whenever a drawdown time from the running supremum arrives. Using an excursion-theoretical approach, for such a reflected process we find the Laplace transform of the upper exiting time and an expression of the associated potential measure. When the reflected process is identified as a risk process with capital injections, the expected total amount of discounted capital injections prior to the exiting time and the Laplace transform of the accumulated capital injections until the exiting time are also obtained. The results are expressed in terms of scale functions for the spectrally negative Levy process.

The first isolable Ge5-spiropentadiene 1 was synthesized via the reduction of (iPr3Si)2NGeCl (3) with potassium. The crystal structure of 1 reveals a spirocyclic Ge5 skeleton containing two Ge-Ge double bonds (avg. 2.34 A), which are fettered in two Ge3 rings with a dihedral angle of 70.193°. The DFT calculations and orbital analysis show that the σ-delocalization of the Ge5 skeleton and the 2π-delocalized aromatic Ge3 rings enhance the stability of molecule 1.

The interaction of molecular hydrogen with a ZnO(1010) surface at cryogenic conditions was investigated by in situ scanning tunneling microscopy (STM) experiments combined with density functional ...

A new stable six-membered cyclic germylene radical C (•L3Ge:; •L3 = •[CH3C(PhCN–Dip)2]2–, where Dip = 2,6-iPr2C6H3) has been synthesized and structurally characterized. Unlike the germanium-centere...

An isogeometric scaled boundary finite element method (IGA-SBFEM) using the non-uniform rational B-splines (NURBS) is firstly performed to investigate the liquid sloshing in the half-full horizontal circular cylindrical with the internal bodies. The proposed method can effectively maintain the advantages of the SBFEM, which combines the advantages of the finite element method and the boundary element method with its own unique characteristics, with the analytical solutions in the radial direction, and also can accurately improve the description of geometry on the boundary by using the NURBS, which brings out the flexibility to describe the complex geometry and presents some key improvements compared to the traditional SBFEM. The detailed derivation and solutions for the sloshing problems based on IGA-SBFEM, and the sloshing frequencies and the corresponding mode shapes and the dynamic sloshing characteristics are also presented by combining the multimodal method. The numerical results validate that this proposed method can acquire higher accuracy, efficiency and convergence with significantly fewer degrees of freedom than those of the traditional SBFEM, and the total number of degrees of freedom of IGA-SBFEM and SBFEM is far less than those of FEM which should be discretized in the entire domain. A detailed parametric study for estimating the influences of the key parameters involving the arrangement, shape, number and size of the internal bodies on the natural sloshing frequencies, mode shapes and sloshing forces and some interesting conclusions have been obtained.

This study investigated the alloying effects of 0.4 wt.% Sc on the microstructure, mechanical properties, and fracture behavior of a cast Be-Al alloy prepared by vacuum induction melting. The micromechanics of Sc-containing secondary-phase particles (SPs) were characterized by nanoindentation, and the fracture behavior of the alloy was investigated via tensile fractography and optical metallography. The addition of 0.4 wt.% Sc significantly modified the alloy microstructure by decreasing the secondary dendritic arm spacing (SDAS), weakening the dendritic structure of Be, and producing an equiaxed/cellular alloy microstructure with refined Be grains. Sc alloying increased the Vickers hardness by 36%, elastic modulus by 28%, yield strength by 35%, ultimate strength by 52%, but decreased the elongation from 3.6 to 2.9%. Sc-containing SPs had a higher elastic modulus, yield strength, microhardness, and a lower plasticity index than the Be and Al matrices, resulting in interface separation during the fracture process. SPs located at the Be/Al interfaces did not act as microcrack sources for the matrices, whereas highly faceted SPs within the Be grains induced microcrack formation and decreased the elongation. The failure mode of the cast Be-Al-0.4Sc alloy still involved the brittle cleavage failure of Be regions and ductile dimple failure of Al regions, which was not the case with the cast Be-Al alloy.

The adsorption and organization state of methanol on the ZnO surface is of importance for understanding the mechanism of the related (photo)catalytic reactions. In this work, by using high-resoluti...

This paper is devoted to the study of a risk-based optimal investment and proportional reinsurance problem. The surplus process of the insurer and the risky asset process in the financial m...

Voltage-dependent anion channels (VDACs) are the most abundant proteins in the mitochondrial outer membranes of all eukaryotic cells. They participate in mitochondrial energy metabolism, mitochondria-mediated apoptosis, and cell growth and reproduction. Here, the chromosomal localizations, gene structure, conserved domains, and phylogenetic relationships were analyzed. The amino acid sequences of VDACs were found to be highly conserved. The tissue-specific transcript analysis from transcriptome data and qRT-PCR demonstrated that grapevine VDACs might play an important role in plant growth and development. It was also speculated that VDAC3 might be a regulator of modulated leaf and berry development as the expression patterns during these developmental stages are up-regulated. Further, we screened the role of all grape VDACs’ response to pathogen stress and found that VDAC3 from downy mildew Plasmopara viticola-resistant Chinese wild grapevine species Vitis piasezkii “Liuba-8” had a higher expression than the downy mildew susceptible species Vitis vinifera cv. “Thompson Seedless” after inoculation with P. viticola. Overexpression of VpVDAC3 resulted in increased resistance to pathogens, which was found to prevent VpVDAC3 protein accumulation through protein post-transcriptional regulation. Taken together, these data indicate that VpVDAC3 plays a role in P. viticola defense and provides the evidence with which to understand the mechanism of grape response to pathogen stress.

Antibody-drug conjugates (ADCs) are complex pharmaceutical molecules that combine monoclonal antibodies with biologically active drugs through chemical linkers. ADCs are designed to specifically kill disease cells by utilizing the target specificity of antibodies and the cytotoxicity of chemical drugs. However, the traditional ADCs were only applied to a few disease targets because of some limitations such as the huge molecular weight, the uncontrollable coupling reactions, and a single mechanism of action. Here we report a simple, one-pot, successive reaction method to produce dual payload conjugates with the site-specifically engineered cysteine and p-acetyl-phenylalanine using Herceptin (trastuzumab), an anti-HER2 antibody drug widely used for breast cancer treatment, as a tool molecule. This strategy enables antibodies to conjugate with two mechanistically distinct cytotoxic drugs through different functional groups sequentially, therefore, rendering the newly designed ADCs with functional diversity and the potential to overcome drug resistance and enhance the therapeutic efficacy.

Centimeter-sized samples of hypereutectic Al–15 mass% Fe alloy were manufactured by a laser powder bed fusion (L-PBF) process while systematically varying laser power (P) and scan speed (v). The effects on relative density and melt pool depth of L-PBF-manufactured samples were investigated. In comparison with other Al alloys, a small laser process window of P = 77–128 W and v = 0.4–0.8 ms–1 was found for manufacturing macroscopically crack-free samples. A higher v and P led to the creation of macroscopic cracks propagating parallel to the powder-bed plane. These cracks preferentially propagated along the melt pool boundaries decorated with brittle θ-Al13Fe4 phase, resulting in low L-PBF processability of Al–15%Fe alloy. The deposited energy density model (using P·v−1/2) would be useful for identifying the optimum L-PBF process conditions towards densification of Al–15%Fe alloy samples, in comparison with the volumetric energy density (using P·v−1), however, the validity of the model was reduced for this alloy in comparison with other alloys with high thermal conductivities. This is likely due to inhomogeneous microstructures having numerous coarsened θ–Al13Fe4 phases localized at melt pool boundaries. These results provide insights into achieving sufficient L-PBF processability for manufacturing dense Al–Fe binary alloy samples.

International audience; We report here a dinuclear DyIII iodine-bridged single-molecule magnet self-assembled by cis/trans coordination chemistry that displays a large anisotropy barrier of ca. 1300 K and a hysteresis opening temperature of 16 K. High temperature quantum tunnelling of magnetization is observed up to 56 K in zero-field and explained by the combination of the large anisotropy barrier and the local transverse field at the trans site. The results provide a model for thorough understanding of the effect of electronic structure on the magnetic behavior of lanthanide complexes.

In this paper, we investigate the problem of optimal strategies of dividend and reinsurance under the Cram\'{e}r-Lundberg risk model embedded with the thinning-dependence structure which was firstly introduced by Wang and Yuen (2005), subject to the optimality criteria of maximizing the expected accumulated discounted dividends paid until ruin. To enhance the practical relevance of the optimal dividend and reinsurance problem, non-cheap reinsurance is considered and transaction costs and taxes are imposed on dividends, which converts our optimization problem into a mixed classical-impulse control problem. For the purpose of better mathematical tractability and neat, explicit solutions of our control problem, instead of the Cram\'er-Lundberg framework we study its approximated diffusion model with two thinly dependent classes of insurance businesses. Using a method of quasi-variational inequalities, we show that the optimal reinsurance follows a two-dimensional excess-of-loss reinsurance strategy, and, the optimal dividend strategy turns out to be an impulse dividend strategy with an upper and a lower barrier, i.e., every thing above the lower barrier is paid as dividends each time the surplus is above the upper barrier, otherwise no dividends are paid. Closed-form expression for the value function associated with the optimal dividend and reinsurance strategy is also given. In addition, some numerical examples are presented to illustrate the optimality results.

As a carbonate-hosted deposit, the Huamuqing Pb–Zn deposit is situated in the western margin of the Yangtze Block. The strata-bound, irregular or vein-type Pb–Zn orebodies of the Huamuqing Pb–Zn deposit are mainly hosted by carbonate rocks of the Sinian Dengying Formation or Cambrian Meishucun Formation. Ores metallic minerals include mainly sphalerite, galena, and pyrite, whereas non-metallic minerals include mainly quartz and calcite. The alteration/mineralization can be divided into three stages: (I) the pyrite-quartz stage, (II) the polymetallic sulfide-quartz stage, and (III) the pyrite-calcite stage. The C–O isotopes of stage III hydrothermal calcite and multi-isotopes (S, Pb, Rb, Sr) of stage II sulfides were analyzed to constrain the ore-forming material source and mineralization timing at Huamuqing. The ranges of δ13CPDB and δ18OSMOW values for the stage III calcites are from − 0.641 to + 0.180‰ and + 17.542 to + 18.443‰, respectively. This suggests that the carbon of stage III was mainly derived from the Sinian dolostone, and the O isotope signatures of stage III were probably in connection with water/rock (W/R) interactions between the δ18O-depleted fluids and δ18O-enriched Sinian dolostone. The stage II sulfide δ34SCDT values vary from + 13.037 to +20.696‰, indicating that the reduced sulfur was originated mainly from Sinian to Triassic evaporites. The stage II sulfide 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ranges are from 18.184 to 18.393, 15.575 to 15.691, and 38.325 to 38.436, respectively. This demonstrates multiple Pb sources, which may have included sedimentary rocks, basement rocks, and basalts. Initial 87Sr/86Sr ratios of eight sphalerite samples range from 0.70815 to 0.71399, indicating that the ore fluids most probably came from or percolated through basement rocks, basalts, and sedimentary rocks. The mineralization timing was sphalerite Rb–Sr dated to be Late Triassic (204 ± 2 Ma), reflecting the Huamuqing deposit formed during late Indosinian. Hence, the Huamuqing deposit is a carbonate-hosted, thrust fault–controlled epigenetic Pb-Zn deposit that has a mixed source of ore-forming metals and ore-forming fluids.

Data visualizations typically show a representation of a data set with little to no focus on the repeatability or generalizability of the displayed trends and patterns. However, insights gleaned from these visualizations are often used as the basis for decisions about future events. Visualizations of retrospective data therefore often serve as “visual predictive models.” However, this visual predictive model approach can lead to invalid inferences. In this article, we describe an approach to visual model validation called Inline Replication. Inline Replication is closely related to the statistical techniques of bootstrap sampling and cross-validation and, like those methods, provides a non-parametric and broadly applicable technique for assessing the variance of findings from visualizations. This article describes the overall Inline Replication process and outlines how it can be integrated into both traditional and emerging “big data” visualization pipelines. It also provides examples of how Inline Replication can be integrated into common visualization techniques such as bar charts and linear regression lines. Results from an empirical evaluation of the technique and two prototype Inline Replication–based visual analysis systems are also described. The empirical evaluation demonstrates the impact of Inline Replication under different conditions, showing that both (1) the level of partitioning and (2) the approach to aggregation have a major influence over its behavior. The results highlight the trade-offs in choosing Inline Replication parameters but suggest that using [Formula: see text] partitions is a reasonable default.

A highly ordered copper(i) oxide film grown on a Pt(111) substrate exhibits extremely high reactivity to CO molecules. Systematic scanning tunneling microscopy experiments in combination with density-functional theory calculations demonstrate that the reaction occurs at the peripheries of the Cu2O islands where low-coordinated oxygen atoms are located.

The main contribution of this paper is to determine the allocation strategy of on-shore power supply (OPS), comprising additional power capacity of OPS and adopting patterns of OPS at berth, to realize the trade-off between total cost of OPS and carbon emissions of ships. Firstly, carbon emission formulations, adopting patterns of OPS and arrival patterns of ships are described. Then, in order to minimize total cost and carbon emissions, an integer programming model for OPS allocation problem is proposed. Next, a simulation-based solution method is developed to resolve the optimization model, which consists of inner simulation module and outer optimization module. The outer module enumerates all the allocation scenarios and evaluates the results from the inner module. The inner module introduces a simulation model to represent the stochastic operation system in the container terminal and outputs results to outer module. Finally, taking a port in China as an example, this paper designs and conducts a series of experiments and discovers that the sensitivity of results emphasizes the importance of electricity price on the optimal allocation. When electricity price is lower or larger than 0.3 $/kWh, the optimal power capacity is 9200 or 5230 kW, correspondingly.

The cast Be-Al-0.4Sc-0.4Zr alloy is attractive for potential applications in numerous fields owing to the advantageous performance closely related to its microstructure and mechanical properties. This work investigates the microstructure and micro-mechanical properties of this alloy using various characterizing methods. In addition to the pronounced microstructure modifications, it was determined that both the scandium (Sc) and zirconium (Zr) preferentially formed intermetallic compounds with Be in the melt, and the majority of secondary phases existed in the Al matrix rather than the Be matrix. The calculated disregistry of lattice spacing, all greater than 15%, for the Al3Sc/Be and Be13Sc/Be couples indicated the secondary phase particles (SPs) did not act as effective nucleation sites for the Be. The calculated Gibbs energy and thermal analysis results both revealed, for the first time, that the Be13Sc formed spontaneously in the melt below the temperature of 1350 °C. Micro-mechanics including the reduced modulus and micro-hardness of the dispersed SPs (approximately 300 GPa and 16 GPa), the Be (approximately 320 GPa and 5.2 GPa) and Al (approximately 166 GPa and 0.6 GPa) matrices were determined by nano-indentation. The pop-in events at the depth near 10 nm on the load–depth curves for the SPs and the Be phase were attributed to the surface oxide layer, whereas those near 30 nm were due to their intrinsic properties. The true micro-hardness of the SPs and the Be phase were determined to be 4.68 GPa and 15.46 GPa via material pile-up corrections. The mechanism embodied by the homogeneous dislocation nucleation and propagation for the SPs was facilely concluded with the critical shear stress of 6.0 GPa and dislocation loop radius of 2.7 nm obtained.

Inspired by some works of Kirkby, J. L. [2015. Efficient option pricing by frame duality with the fast Fourier transform. SIAM Journal on Financial Mathematics 6(1), 713–747; 2016. An efficient tra...

In this paper we consider the joint Laplace transform of occupation times over disjoint intervals for spectrally negative Levy processes with a general loss-carry-forward taxation structure. This tax structure was first introduced by Albrecher and Hipp in their paper in 2007. We obtain representations of the joint Laplace transforms in terms of scale functions and the Levy measure associated with the driven spectrally negative Levy processes. Two numerical examples, i.e. a Brownian motion with drift and a compound Poisson model, are provided at the end of this paper and explicit results are presented with discussions.

Supported metal films are often found to display extraordinary properties compared to their bulk counterparts. In this work, we investigate the atomic and electronic structures of both the Au/Cu(11...

The literature has been witnessing an aroused interest in the study of the two-side exit problems for various models. Motivated by Kyprianou and Zhou (2009) and Li et al. (2018), the present paper concerns the two-side exit problems of the taxed spectrally negative Levy risk process involving the general draw-down time. Our two-side exit problem is separated into two sub-problems: one being the Laplace transform of the up-exiting time of a certain level on the event that the taxed risk process up-crosses that level before the general draw-down time; the other being the Laplace transform of the draw-down time on the event that draw-down of the taxed risk process occurs before it up-crosses a certain level. Using a modified approximating method of Li et al. (2018) together with the excursion theory, solutions for the aforementioned two-side exit problems are obtained.

In this paper, according to a certain criterion, we divide the exponential distribution class into three subclasses. One of them is closely related to the regular-variation-tailed distribution class, so it is called the semi-regular-variation-tailed distribution class. In the class, although all distributions are not convolution equivalent,they still have some good properties. We give the precise tail asymptotic expression of convolution of these distributions, and prove that the new class is closed under convolution. In addition, we do not need to require the corresponding random variables to be identically distributed. Finally, we apply these results to a discrete time risk model with stochastic returns, and obtain the precise asymptotic estimation of the finite time ruin probability.

For spectrally negative Lévy risk processes we consider a general version of de Finetti's optimal dividend problem in which the ruin time is replaced with a general drawdown time from the running maximum in its value function. We identify a condition under which a barrier dividend strategy is optimal among all admissible strategies if the underlying process does not belong to a small class of compound Poisson processes with drift, for which the take-the-money-and-run dividend strategy is optimal. It generalizes the previous results on dividend optimization from ruin time based to drawdown time based. The associated drawdown functions are discussed in detail for examples of spectrally negative Lévy processes.

Oxide formation on surface of nitrogen-rich uranium nitride film/particles was investigated using X-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), aberration-corrected transmission electron microscopy (TEM), and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) coupled with electron energy-loss spectroscopy (EELS). XPS and AES studies indicated that the oxidized layer on UN2-x film is ternary compound uranium oxynitride (UNxOy) in 5–10 nm thickness. TEM/HAADF-STEM and EELS studies revealed the UNxOy crystallizes in the FCC CaF2-type structure with the lattice parameter close to the CaF2-type UN2-x matrix. The work can provide further information to the oxidation mechanism of uranium nitride.

This paper considers an optimal investment and risk control problem under the criterion of logarithm utility maximization. The risky asset process and the insurance risk process are described by stochastic differential equations with jumps and anticipating coefficients. The insurer invests in the financial assets and controls the number of policies based on some partial information about the financial market and the insurance claims. The forward integral and Malliavin calculus for Levy processes are used to obtain a characterization of the optimal strategy. Some special cases are discussed and the closed-form expressions for the optimal strategies are derived.

The interaction of CO on the clean and a CO2-precovered ZnO(1010) surface has been investigated with low-temperature scanning tunneling microscopy in combination with density-functional theory calculations. On the clean surface, CO binds weakly to the surface Zn ions and diffuses readily along the [1210] direction even at liquid nitrogen temperature. In contrast, the presence of CO2 significantly enhances the binding strength of the CO molecules in the vicinity and in turn suppresses their diffusion. These findings are believed to provide new insights of the atomistic interactions of distinct reagents on the ZnO surface, and hence shed light onto the roles of ZnO in the syngas-involved catalytic reactions.

A new digermylene has been synthesized through the reaction of a six-membered cyclic radical germylene precursor with a mixture of CoBr2 and a seven-membered N-heterocyclic carbene. The density functional theory simulation on the geometry of the digermylene agrees well with the experimental X-ray diffraction result. The digermylene possesses the shortest GeI–GeI bond [2.4853(6) A] compared to the known singly bonded analogues, which can be attributed to σ → π* conjugation. In addition, it is revealed that a stable dative bond cannot form for the reductive radical germylene with the oxidative metal centers.

The microstructure modification, mechanical property reinforcement, and thermal behaviors of arc-melted casting beryllium-aluminum (Be-Al) alloys with the addition of various contents of scandium (Sc) were studied in this work. The addition of 0.2wt% Sc shortened the secondary dendritic arm spacing (SDAS) of Be dendrites; the addition of 0.4wt% Sc further decreased the SDAS, weakened the dendritic structure of Be, and afforded equiaxed/cellular alloy microstructure with the finest Be grain size; however, higher additions of Sc till 3.0wt% enlarged the SDAS of Be and coarsened the Be grains. An explanation for the microstructure variation was proposed. The addition of Sc resulted in the formation of intermetallic compounds Be 13 Sc and Al 3 Sc distributed in the Be and Al matrices and along the Be/Al grain boundaries. It was observed that Sc preferentially formed Be 13 Sc and rendered the Be phase less plastic. The addition of Sc increased the hardness and elastic modulus of Be-Al alloys while strengthening the Be phase to a higher extent than Al. Thermal analysis showed that the Al phase had the highest latent heat of 167.6 J/g during melting and a low nucleation undercooling of 16.4 °C during solidification with the addition of 0.4wt% Sc. Heat treatment and water quenching changed the relative contents of Be 13 Sc and Al 3 Sc and further strengthened the alloys.

We investigated the atomic and electronic properties of (1 0 0) stacking fault (SF) in undoped and La-doped BaSnO3 by first-principles calculations. It was found that 1/2[1 1 1] (1 0 0) SF is energetically favorable when Ba atoms occupy the interface while 1/2 (1 0 0) [1 0 1] SF becomes the most stable when the SF interface is occupied by Sn atoms. SF influences the distribution of La dopant and the electric properties of the system. In the presence of SF, electronic states near the Fermi level decrease and the bandgap expands by about 0.6 eV. Our results suggest that SF is one of the possible origins for the performance degradation.

Millimeter-wave (mm-wave) communication is a practicable scheme for big data communication, such as next-generation cellular communication. However, because mm-wave frequencies have an extremely large path loss, in order to mitigate the mm-wave path loss, a large number of antennas are packed for beamforming. Conventional multiple-input multiple-output (MIMO) beamforming uses digital processing, which leads to needing extremely giant energy. Hybrid analog/digital beamforming could serve as an awesome technique to reduce the cost. It is essential for achieving high beamfroming gain that accurate mm-wave channel information should be attained at the transmitter. This paper concentrates on the channel state information (CSI) acquirement problem in mm-wave communication systems with massive MIMO arrays. Because of the CSI acquirement, a method of significant overhead, we consider an accurate channel estimation scheme with low overhead. Not only do we in this paper propose using support information extracted at Sub-6GHz to aid the mm-wave CSI acquirement but also introduce a strategy used in the mm-wave channel estimation. We, in particular, formulate mm-wave CSI acquirement as a compressive sensing problem and obtain the CSI by using Bernoulli–Gaussian generalized approximate message passing (BG-GAMP) algorithm. We also extend the BG-GAMP algorithm with support distribution information from sub-6-GHz channel. Furthermore, based on the $K$ nearest neighbor idea, we redesign the BG-GAMP algorithm depending on sub-6-GHz support distribution information. Details of BG-GAMP with the nearest neighbor learning algorithm that is built on support distribution information from sub-6-GHz channel would also be revealed. Simulation results show the out-of-band information aided mm-wave channel estimation is capable of reducing the pilot overhead greatly and channel estimation accuracy improved as well.

Five novel donor-acceptor-donor (D-A-D) type monomers (VQ1 ~ VQ5) with a common V-shape configuration have been developed and further electropolymerized for electrochromic applications. The monomers were designed by introducing two triphenylamine groups into the 2- and 3- position of the quinoxaline derivates, respectively. These redox-active monomers could be electrodeposited robustly on the ITO electrodes in an electrolyte solution via the oxidative coupling reactions between triphenylamine radical cations. The obtained thin polymer films (PVQ1 ~ PVQ5) exhibited reversible redox behaviours and obvious color changes upon voltage variation. All these polymers exhibited excellent electrochromic performances involving high optical contrast (over 70%), short response time (less than 2 s) and high coloration efficiency (over 200 cm2 C−1). Moreover, the optical properties of these polymers in both neutral state and oxidation state can be tuned by variation of the additional substituents on the quinoxaline parts, respectively.

We investigate the gap solitons of Bose–Einstein condensate in honeycomb optical lattices. It is found that the two-dimensional honeycomb optical lattices admit multipole gap solitons. These multipoles can have their bright solitary structures be in-phase or out-of-phase. The nonlinear dynamical stabilities of these solitons are investigated using direct simulations of the Gross–Pitaevskii equation. For the unipole gap solitons, the nonlinear evolution shows dynamical stability or instability, which depends on the properties of atomic interactions and the dependence of soliton power. A fascinating property of dipole gap solitons is that they can present self-trapping or tunneling instabilities under atomic nonlinearity. The in-phase and out-of-phase of multipole gap solitons support different tunneling or self-trapping regimes. These results have an application to investigations of localized structures in nonlinear optics and Bose–Einstein condensate.

Ship emissions is one of the main components of port pollution. Inefficient waterway management may not only result in additional waiting time of ships, but also the aggravated emissions in port. With special consideration of combining scheduling optimization and speed reduction of ships in port, this paper proposed a new emission reduction method, called ship scheduling with speed reduction (SSSR). Performance of the SSSR method has been testified through comparisons between the new and traditional ship emission reduction methods based on the navigation safety under three different strategies. The effectiveness of the new ship emission reduction method has been testified through a series of experiments with practical data in port. Especially, under various stages in port, the emissions of ships can be reduced by 8.0%–11.9% and the traffic efficiency can be improved by 3.8%–6.2%.

A technique to study effect of various baffles on liquid oscillations in partially filled rigid toroidal tanks is first developed by extending the semi-analytical scaled boundary finite element method (SBFEM), which utilizes the advantages of both the boundary element (BEM) and finite element methods (FEM). As found in the BEM, only the boundary is discretized to reduce the space by one, and no fundamental solution is needed unlike the BEM. The calculated liquid domain is divided into several simple sub-domains so that the liquid velocity potential in each liquid sub-domain becomes the class C 1 with continuity boundary conditions. Based on the linear potential theory and weighted residual method, the semi-analytical solutions of the liquid velocity potential corresponding to each sub-domain are obtained by means of SBFEM, where the geometry of each sub-domain is transformed into scaled boundary coordinates, including the radial and circumferential coordinates by using a scaling centre, and the finite-element approximation of the circumferential coordinate yields the analytical equation in the radial coordinate. By discretizing the flow boundaries, the integral equation governed on the boundary is formulated into a general matrix eigenvalue problem. Based on the eigenvalue problem and multimodal method, an efficient methodology is adopted to computer the sloshing masses and sloshing force. Accuracy, simple and fast numerical computations are observed by the convergence study, and excellent agreements have been achieved in the comparison of results obtained by the proposed approach with other methods. Meanwhile, several baffle configurations are considered including the horizontal bottom-mounted and surface-piercing ring baffles as well as their combination form, bottom-mounted and surface-piercing ring baffles as well as their combination, and free surface-touching baffles. The effects of baffled arrangement, the ratio b / a of elliptical cross section, liquid fill level, and baffles' length upon the sloshing frequencies, the associated sloshing mode shapes and sloshing forces are investigated in detail and some conclusions are outlined. The results show that the present method allows for the simulation of complex 3D sloshing phenomena using a relative small number of degrees of freedom while the mesh consists of two-dimensional elements only.

Taking advantage of the steric hindrance and charge-driving effects, four air-stable pentagonal bipyramidal mononuclear DyIII compounds were hydrothermally synthesized. With a tetradentate ligand, N,N'-bis(2-methylenepyridinyl)ethylenediamine (Bpen), invariably coordinates to DyIII in an equatorial plan, 1-3 achieve an orderly transformation of the ligand field by sequentially replacing the remaining sites of the DyIII ion. Compound 4 possesses the same coordination atoms but a different peripheral coordination sphere with 3. Magnetic characterizations display that the compounds are field-induced single-ion magnets (SIM) with actually low barriers, even though 2 has both the same atoms and a similar geometry of the first sphere compared with [Dy(bbpen)Cl] (2', H2 bbpen=N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-methylpyridyl)ethylenediamin), a high-performance SIM previously reported. Detailed ab initio calculations have been employed to further elucidate the electronic and magnetic structure of the low-lying energy levels of compounds 1-4 and 2'. The theoretical results indicate there is an apparent difference in the electronic structure for these compounds. The analysis on the electrostatic potential further demonstrates that although the pentagonal bipyramidal D5h is one of the ideal configurations expected, the electron density of the donor atoms from the different hybridizations and other functional groups, outside the first sphere, should also be considered in the rational design of promising molecular magnets.

Rail transport plays an important role in port-based freight flows. In the context of port competition, the change of inland transport modes would directly influence pricing strategies and profits of ports. Therefore, this paper provides a method to analyze how the introduction of rail transport services affect port competition. Firstly, a two-stage game model is constructed based on a Hotelling model, which consists of two ports and one rail operator. Then, this paper demonstrates how the existence of pure strategy equilibrium prices of ports depends on the value of marginal profits of rail transport services. After comparing the results of different situations, our analysis shows there is a negative effect on ports' service prices and profits when the rail transport services are introduced in the port. As shown in the numerical example, the profits of ports would be reduced by about 10% (when rail transport services are only provided to one port) and 20% (provided to both ports) respectively. From the perspective of government, there exists an incentive to support the development of rail transport due to the promotion of social welfare. In addition, the rail operator is also likely to expand rail services in order to improve profits. Finally, the effect of economies of scale of rail transport is extendedly analyzed and three policies are proposed to weaken the loss of ports’ profits, including implementing refunding scheme, setting price floor on port service price and providing government subsidy. The findings in this paper could provide support for the decision making towards comprehensive transportation management in coastal zone.

Great interest is being shown in investigating magnetic interactions that efficiently influence lanthanide single-molecule magnet behavior. A series of heterometallic complexes [M2Ln2(Hhms)2(CH3COO)6(CH3OH)2(H2O)2]·(NO3)2 (M = NiII, Ln = DyIII (1), GdIII (2), and YIII (3); M = CoII, Ln = DyIII (4), GdIII (5), and YIII (6)) have been prepared with a compartmental Schiff-base ligand, 1-(2-hydroxy-3-methoxybenzylidene)-semicarbazide (H2hms), featuring a zigzag-shaped MII-LnIII-LnIII-MII metallic core arrangement. In complexes 1–6, a unique monophenoxo/diacetate asymmetric bridging connects MII ion with LnIII ion, and four acetates bridge two LnIII ions where acetates play essential roles as coligand in generating the tetranuclear units. Magnetic studies reveal the presence of predominant ferromagnetic coupling in DyIII and GdIII derivatives, and slow relaxation of magnetization is observed for {Ni2IIDy2III} and {CoII2DyIII2} with an energy barrier of 16.0 K for {Ni2IIDy2III} and 6.7 K for {CoII2DyIII2} under...

A multiplicative regression model with longitudinal data is introduced, and a least product relative errors estimate is constructed based on relative errors. Generally, the least squares criterion and least absolute deviation criterion based on absolute errors are the most widely used criteria in the regression analysis. However, when response variables have different measurement scales, relative errors may be superior to absolute errors. Thence, we develop a least product relative errors estimator of parameter based on relative errors, and obtain their asymptotic properties where some nuisance parameters such as correlation structure of error terms are included. In addition, block empirical likelihood technique is employed to construct the confidence regions of the corresponding unknown regression parameter, avoiding density estimation. Simulation results confirm that the proposed methods perform well.

The doping effect of Cu on the self-assembly film of melamine on an Au(111) surface has been investigated with scanning tunneling microscopy (STM). The evaporated Cu adatoms occupy the positions underneath the amino groups and change the hydrogen bonding pattern between the melamine molecules. Accordingly, the self-assembly structure has changed stepwise from a well-defined honeycomb into a track-like and then a triangular structure depending on the amount of Cu adatoms. The interaction between Cu adatom and melamine is moderate thus the Cu adatoms can be released upon mild heating to around 100 °C. These findings are different from previous observations of either the coordination assembly or the physically trapped metal adatoms.

Using the new β-diketimine 1a (PhCH(PhC═N-Dip)2, Dip = 2,6-iPr2C6H3), which possesses three phenyl groups at the ligand backbone, we synthesized the β-diketiminato germylene chloride 2 (LGeCl, L = [PhC(PhCN-Dip)2]−). The β-diketiminato germanium radical complex 3 (•LGe:, •L = •[PhC(PhCN-Dip)2]2–) has been isolated by reduction of LGeCl with sodium/naphthalene in 64% yield. X-ray diffraction, HR-MS, and electron paramagnetic resonance analyses together with DFT calculations reveal that 3 exhibits a remarkably different structure in comparison with the reported Ge(I) radical C (L′•Ge:, L′ = [HC(tBuCN-Dip)2]−). The inductive effect of three phenyl groups leads to the backbone of ligand 1 being more electron deficient, and therefore the singly occupied molecular orbital (SOMO) of radical 3 is mainly composed of a π-antibonding orbital between the N and C atoms. This results in ca. 0.14 A shorter N–Ge bonds and ca. 0.1 A longer C–N bonds in 3 in comparison to those observed in C. Thus, the radical 3 is a two-c...