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Moving loads will have a certain impact on the safety of the structures. Since concrete is a viscoelastic material, the elastic concrete model cannot describe its viscoelastic characteristics under moving loads. It is necessary to establish a model that can describe the viscoelastic characteristics of concrete materials. In addition, the layered of the soil is also an important factor affecting the propagation of subway vibration waves. Considering the effects of the properties of the concrete material of the subway tunnel structure and the layered soil foundation as well as the load velocity on the vibration of the ground surface caused by the moving load, the standard linear elastic solid Euler beam model is described for the subway tunnel structure in this paper. The equivalent stiffness of the layered soil-viscoelastic beam coupling system subjected to a moving load is formed by using the transmission and reflection matrix (TRM) method. The numerical solution of ground surface displacement caused by subway tunnel in time-space domain is obtained by IFFT algorithm. The correctness of the algorithm is verified by comparing with the reference results. Numerical results show that, with the increase of the viscous coefficient of the viscoelastic Euler beam, the vibration amplitude of the ground surface will decrease. Up to a certain value of the increasing the viscous coefficient of the Euler beam, it will have little effect on the vibration amplitude of the ground surface. Therefore, the standard solid model of viscoelastic Euler beam can well describe the creep and relaxation of materials. The model of viscoelastic beam is reasonable for the working condition of subway tunnel concrete structure. At high speed of moving load, the maximum value of ground surface displacement spectrum will appear at the smaller frequency domain and the maximum value of displacement spectrum will also increase for the soft layer soil, while it is opposite to that of the stiffer layer soil.

A cheap and compact Nd:YVO4 laser at 1087.5 nm pumped by an edge-emitting laser diode (LD) array is demonstrated. By specially restraining the other lines at 1064.1, 914.0, and 1342.0 nm with a refined output mirror having low-reflectivity at 1064.1 nm (R1064.1 = 3%) and high-reflectivity (R1087.5 = 92%) at 1087.5 nm, a low-gain line at 1087.5 nm is achieved. The output power is 8.79 W at the 807.9 nm pump power of 37.43 W with an optical-optical conversion efficiency of 23.5%.

Zinc oxide (ZnO) has drawn much attention due to its excellent optical and electrical properties. In this study, ZnO film was prepared by a high-deposition-rate spatial atomic layer deposition (ALD) and subjected to a post-annealing process to suppress the intrinsic defects and improve the crystallinity and film properties. The results show that the film thickness increases with annealing temperature owing to the increment of oxide layer caused by the suppression of oxygen vacancy defects as indicated by the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) spectra. The film transmittance is seldom influenced by annealing. The refractive index increases with annealing temperature at 300&ndash, 700 &deg, C, possibly due to higher density and crystallinity of the film. The band gap decreases after annealing, which should be ascribed to the decrease in carrier concentration according to Burstein&ndash, Moss model. The carrier concentration decreases with increasing annealing temperature at 300&ndash, C since the oxygen vacancy defects are suppressed, then it increases at 800 &deg, C possibly due to the out-diffusion of oxygen atoms from the film. Meanwhile, the carrier mobility increases with temperature due to higher crystallinity and larger crystallite size. The film resistivity increases at 300&ndash, C then decreases at 800 &deg, C, which should be ascribed primarily to the variation of carrier concentration.

High power impuls magnetron sputtering (HiPIMS) deposits high quality films due to high ionization fraction. In this work, Indium tin oxide (ITO) films are deposited by HiPIMS methord. The effects of annealing temperature under nitrogen environment on the crystal structure, optical properties and electrical properties of ITO films were investigated. The properties of the films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), Hall measurement system (Hall), and UV-Vis spectrophotometer. The results showed that the average visible transmittance of the annealed ITO film reached 83.5%. The XRD results show that the ITO film grain size slightly increased after annealing. The mobility increases after annealing. This study proves that HiPIMS deposited ITO thin film is very superior to low temperature processing, and the grown thin film can be used in LEDs and solar cells.

Indium tin oxide (ITO) film was prepared by an in-line magnetron sputtering system equipped with a high power impulse power source. The influences of working pressure on the film deposition mechanism and properties were investigated. The excitation/ionization level of the sputtered species increases with working pressure as indicated by optical emission spectra. The Sn/In atomic ratio and oxygen vacancy concentration in the film decreases as working pressure increases due to unequally increasing ionization rate and self-sputtering yield of Sn and In atoms and stronger oxidizing activity of oxygen species. As a result, The film resistivity, transparency and optical band gap increase with working pressure. ITO film with a low resistivity of 3.7 × 10−3 Ω·cm and a high transmittance at 380–800 nm of over 84.7% can be obtained when deposited at a working pressure of 8 × 10−2 Torr.

High-mobility, p-type LixCuyO films are prepared by co-dosed plasma-enhanced atomic layer deposition. The x-ray diffraction patterns show that in addition to the CuO and Cu2O phases, the formed LiCu3O3 is responsible for the high mobility. The 350°C-annealed LixCuyO film has transmittance of 85% at mid-long wavelengths and bandgap of 2.4 eV. A hole mobility of 88 cm2V-1s-1 is reached, significantly higher than that of common p-type metal oxides.

Aluminum-doped ZnO (AZO) films are prepared by using spatial atomic layer deposition (ALD). The precursors of trimethylaluminum (TMA) and diethylzinc (DEZ) are concurrently introduced into the deposition region. The amount ratio of TMA to DEZ vapor molecules is controlled by varying the temperature of the precursor bubblers from 5° to 77 °C. It is found that the Al doping level can be predicted using the amount ratio of TMA to DEZ output vapors. The film prepared at the bubbler temperature of 41 °C exhibits an Al content of ~1% and a low resistivity of 3.5 × 10−4 Ω-cm comparable to indium tin oxide films. Furthermore, the Al-doping efficiency is as high as 73%. This study is useful in applying the ALD technique to films with multicomponent oxides.

In this paper, indium oxide (In2O3) thin films are prepared by plasma-enhanced atomic layer deposition (PEALD) using cyclopentadienylindium(I) (InCp) as the metal precursor and O2 plasma as the oxidant. The mechanism and effects of annealing temperature under the air atmosphere on optical, structural, and electrical properties of the films are investigated. The experimental results show that both of the as-deposited and annealed films are polycrystalline bixbyite-cubic structure. No significant influences on the optical properties are observed when the annealing temperature increases from 300 to 600 °C. However, it is confirmed the filling of oxygen vacancy defects by the in-diffused oxygen atoms from the annealing ambient. The carbon impurities resulting from the incompletely reacted InCp are found to be at the interstitial sites in the In2O3 lattice, which can be greatly removed by the annealing treatment. As a consequence, the electrical resistivity increases with increasing annealing temperature mainly related to the reduced carrier concentration. This paper is helpful for PEALD In2O3 films to be applied to optoelectronic devices where the suppression of the oxygen defects, carrier concentration, and carbon impurities are required.

Graphene-oxide (GO) as saturable absorber (SA) for a 1342 nm passively Q-switched Nd:YVO 4 laser is reported. This system produces laser pulse as narrow as 329 ns with a repetition rate of 214 kHz and the largest output power of 520 mW. Our results demonstrate that GO can be used as an excellent and efficient SA for Nd 3+ -doped lasers at 1.3 μm.

In this study, amorphous films of molybdenum oxide (MoOx) had been prepared by plasma enhanced atomic layer deposition (PEALD) technique using molybdenum hexacarbonyl (Mo(CO)6) as a metal precursor and the mixture gas of O2/Ar as reactants. The influence of plasma power from 1000–3000 W on PEALD-MoOx films’ structure properties was investigated, and the deposition mechanism was proposed. Based on the results, the plasma power playing a crucial role in depositing MoOx films is concluded. A maximum deposition rate of MoOx films is 0.76 A/cycle, which is achieved at the optimal plasma power of 2000 W owing to the enhancement of plasma radicals’ intensity. The Mo5+ and Mo6+ oxidation states that emerged in all the films were illustrated by x-ray photoelectron spectroscopy studies, which means oxygen deficiency in substoichiometric MoOx films. The proportion of no-lattice oxygen decreases first and then increases with the increase of the plasma power. A low power and a high power may lead to deficient oxidation and obvious ion bombardment effect, respectively, which lead to the reduction of MoOx film quality, as indicated by the refractive index, atomic force microscopy, and scanning electron microscopy. The clarification of the effect of plasma power on PEALD-MoOx thin films is greatly beneficial to the application in high performance electronic devices.

Oxygen vacancy defects play an important role in determining the properties of zinc oxide (ZnO) film. In this study, ZnO film prepared by a high-deposition-rate spatial ALD process was annealed in an oxygen-rich ambient. The variation of oxygen vacancy defects was analyzed. The results show that oxygen vacancy defects were suppressed by the annealing treatment, particularly at 500 °C–700 °C. As a result, the carrier concentration decreases with increasing annealing temperature, leading to the higher film resistivity. In addition, the oxygen atoms segregated to the ZnO/Si interface to form an interfacial oxide layer, leading to an oxygen-deficient ZnO film when annealed at 300 °C–400 °C and the decrease of oxygen atomic ratio when annealed at 500 °C–800 °C. The annealing treatment also induces higher crystallinity with larger crystallite size, leading to a higher mobility. The refractive index increases with annealing temperature at 300 °C–700 °C, possibly due to the structural relaxation, densification and crystallization of the film. However, the annealing treatment has little effect on the film transmittance due to the low optical loss.

We report a compact continuous-wave (CW) eye-safe Nd:YVO4/PPMgLN intra-cavity optical parametric oscillator (IOPO) based on a shared resonator, in that the fundamental laser and signal light share a same single resonator. At a pump power of 10 W, this OPO system produces an output power at 1476.4 nm of 580 mW. Depending on the 3 grating periods of the PPMgLN crystal (28.5, 29.0 and 29.5 μm), we could enable 3 signal wavelengths at 1429.8, 1450.9 and 1476.4 nm, respectively.

This paper considers a two-dimensional persistent monitoring problem by controlling movements of second-order agents to minimize some uncertainty metric associated with targets in a dynamic environment. In contrast to common sensing models depending only on the distance from a target, we introduce an active sensing model which considers the distance between an agent and a target, as well as the agent's velocity. We propose an objective function which can achieve a collision-free agent trajectory by penalizing all possible collisions. Applying structural properties of the optimal control derived from the Hamiltonian analysis, we limit agent trajectories to a simpler parametric form under a family of 2D curves depending on the problem setting, e.g. ellipses and Fourier trajectories. Our collision-free trajectories are optimized through an event-driven Infinitesimal Perturbation Analysis (IPA) and gradient descent method. Although the solution is generally locally optimal, this method is computationally efficient and offers an alternative to other traditional time-driven methods. Finally, simulation examples are provided to demonstrate our proposed results., Comment: 13 pages arXiv, to be published in IEEE Transactions on Control of Network Systems

Based on the fractal geometry theory, the bending form of crack expansion on concrete lining of hydraulic tunnel is described, according to the model of fractal fracture, stress intensity factor of concrete lining crack of hydraulic tunnel is established. Combined with the fracture mechanics theory, the relationship of stress intensity factor on l concrete lining crack is obtained under the hypothesis of crack linear expansion and crack irregular expansion, while the stress intensity factor of latter is less than the former, which is more close to the actual circumstance and more reasonable, whose fractal dimension is obviously larger than the former. The conclusion can provide reference for the engineering design.

At present, there are only a few theoretical models for researching the electrical resistivity characteristics of multi-phase soil-stone composite medium, as it could be influenced by so many factors. Based on the theory structure models of unsaturated soil electrical resistivity put forward by previous researchers, a theoretical model of multi-phase soil-stone composite medium electrical resistivity properties, suitable for both series connection structure and parallel connection structure of soil stone mixture, is proposed, through which the regular patterns under the influence of water content, porosity, soil-rock ratio, and saturation are analyzed. In line with the results, when the composition of particles are not changed, in the order of sensitive, the main factors that affect electrical resistivity characteristics are water content, porosity, and soil-rock ratio.

In order to investigate the leakage amount in the water supply networks in the countryside regions, a new method combined with GIS and DEM to estimate the leakage amount at water supply network nodes has been put forward. It is proposed according to the Chinese node leakage model, and it takes advantage of the strong spatial annalistic function of the GIS. The emphasis is put on the study of the topology relationship of the water supply networks which are built based on the GIS network analysis. And DEM model is used to calculate the elevation at the network nodes. And then the leakage amount of the water supply network nodes is estimated. Finally, specific examples have been verified in order to illustrate that the GIS-based method to estimate leakage amount at the water supply network nodes is efficient.

By using dynamic and static triaxial experiments to test the saturated composite soil-rock medium of different soil-rock ratio. Measure related power indicators and analyze the variation rules and tendency, and make comparative research on the dynamic and static strength of composite mediums with different soil-rock ratio. Studies have shown the tendency that the static strength and internal friction angle increases while the cohesive force increases and then decreases with the decrease in soil-rock ratio. Under the same compactness, the dynamic strength of composite soil-rock medium increases with the decrease in soil-rock ratio, and decreases significantly with the improvement of seismic intensity; For one rock ratio, dynamic cohesive force decreases with the gradual increase of intensity, and decreases faster with the decrease in soil-rock ratio. While the dynamic internal friction angle decreases with the increase of intensity. At the same intensity, which means the same vibration frequency, dynamic cohesive force increases with the decrease in the soil-rock ratio and so does dynamic internal friction angle.

We proposed a novel decoding algorithm for Analog Codes (Reed-Solomon Codes over complex numbers), thesyndrome repairing(SR) algorithm, for gross error correction in signal transmission. Simulations show that, if the number of gross errors is not too large and the amplitude of background noise is small enough (compared to the amplitude of gross errors), the SR algorithm recovers the original signal with nearly the same accuracy as if no gross errors occur upon transmission. In particular, if the transmission is background-noise-free, then the recovery is exact.

A tentative experiment has been conducted on polymer modified cement concrete now widely used. By filtering through 297 kinds of traces of polymer modified cement concrete samples tentatively mixed, we acquire a proper mix proportion, according to which, a total of 75 groups of 225 polymer modified cement concrete specimens are produced. After further selective preference of these specimens, ultrasonic test is done on the selected ones under different loading conditions. Afterwards, signal processing is accomplished by using wavelet transformation and we preliminarily find a kind of acousto-elastic sensitive concrete material which is comparatively sensitive to stress. This kind of material is produced by mixing epoxy resin, styrene-acrylic emulsion, acrylic emulsion, auxiliaries and iron powder into cement concrete together. The sensitivity of ultrasound and stress of this kind of modified concrete behaves preferably well as follows: at the low stress stage, not only the correlativity curve of ultrasound velocity and stress but also the correlativity curve of weighted spectrum area and stress arises apparently. If this kind of material can be applied to the practical engineering successfully, the acousto-elastic test accuracy of the concrete service stress will be greatly improved.

Based on researches on conventional analytical method of the Rayleigh wave testing data, the wavelet theory is introduced to analyze the data and we find that wavelet components of the Rayleigh wave testing data on the scale of 2-1and 2-2are high frequency interference, so we omit them. Afterwards, the coherent analysis, phase-different analysis and power spectrum analysis of the smoothing signal on the scale of 2-2are made to obtain the frequency dispersion curve, which is smoother and more reasonable than that obtained without using wavelet denoising. Besides, the testing data of shear wave is closer to the calculated value. The results indicate that applying wavelet analysis to the disposal of the Rayleigh wave testing data works efficiently.

Two composting piles were prepared by adding to a mixture of rice straw, vegetables and bran: (i) raw soil free from pentachlorophenol (PCP) contamination (pile A) and (ii) PCP-contaminated soil (pile B). It was shown by the results that compost maturity characterized by water soluble carbon (WSC), TOC/TN ratio, germination index (GI) and dehydrogenase activity (DA) was significantly affected by PCP exposure, which resulted in an inferior degree of maturity for pile B. DGGE analysis revealed an inhibited effect of PCP on compost microbial abundance. The bacteria community shifts were mainly consistent with composting factors such as temperature, pH, moisture content and substrates. By contrast, the fungal communities were more sensitive to PCP contamination due to the significant correlation between fungal community shifts and PCP removal. Therefore, the different microbial community compositions for properly evaluating the degree of maturity and PCP contamination were suggested.

Observable operator models (OOMs) generalize hidden Markov models (HMMs) and can be represented in a structurally similar matrix formalism. The mathematical theory of OOMs gives rise to a family of constructive, fast, and asymptotically correct learning algorithms, whose statistical efficiency, however, depends crucially on the optimization of two auxiliary transformation matrices. This optimization task is nontrivial; indeed, even formulating computationally accessible optimality criteria is not easy. Here we derive how a bound on the modeling error of an OOM can be expressed in terms of these auxiliary matrices, which in turn yields an optimization procedure for them and finally affords us with a complete learning algorithm: the error-controlling algorithm. Models learned by this algorithm have an assured error bound on their parameters. The performance of this algorithm is illuminated by comparisons with two types of HMMs trained by the expectation-maximization algorithm, with the efficiency-sharpening algorithm, another recently found learning algorithm for OOMs, and with predictive state representations (Littman & Sutton, 2001 ) trained by methods representing the state of the art in that field.

Background and objectives: Sjogren's syndrome (SS) is a chronic progressive autoimmune disease. The incidence of peripheral nervous system damage in patients with primary SS (pSS) is 10–30%. Previous studies have shown that there are multiple electrophysiological manifestations in pSS patients presenting with peripheral neuropathy. However, there is no consensus on its neuroelectrophysiological manifestations. Peripheral neuropathy associated with pSS is easily confused with peripheral neuropathy of other etiologies. We hope to observe the neuroelectrophysiological manifestations of peripheral neuropathy associated with pSS to assist in the diagnosis of the disease. Design: A prospective case series. Methods: A total of 100 pSS patients with peripheral neuropathy receiving treatment in the Department of Neurology, First Affiliated Hospital of Kunming Medical University, China will be included in this study. Fifty-two patients presenting with peripheral neuropathy associated with pSS have been included in a preliminary investigation. Outcome measures and preliminary results: The primary outcome measure is the incidence of abnormal motor nerve conduction velocity in these patients. The secondary outcome measures are the incidences of abnormalities in terminal motor latencies, compound muscle action potential amplitudes, sensory nerve conduction velocities, sensory nerve action potential amplitudes, F waves, and sympathetic skin responses. The results of 52 patients included in the preliminary study showed that the incidences of each electrophysiological index was similar between the upper and lower extremities. Abnormal motor nerve conduction velocity occurred more frequently than abnormal compound muscle action potential amplitude. Abnormal sensory nerve conduction velocity was observed significantly more often than abnormal sensory nerve action potential amplitude. Abnormal motor nerve conduction velocity had a similar incidence to abnormal sensory nerve conduction velocity. Abnormal compound muscle action potential amplitude had a similar incidence to abnormal sensory nerve action potential amplitude. Abnormal F waves were observed significantly less frequently than abnormal motor nerve conduction study. Abnormal sympathetic skin response was seen with a similar incidence to abnormal motor nerve conduction study. Discussion: The results of this study, as indicated by the preliminary investigation, will reveal the neuroelectrophysiological abnormalities in peripheral neuropathy associated with pSS, which will aid diagnosis of the disease. Ethics and dissemination: This study was approved by Medical Ethics Committee of Kunming Medical University of China on October 14 th , 2005 (approval No. 20051014). The study protocol was designed in September 2016 and registered in April 2018. The study protocol received ethics approval from Medical Ethics Committee of Kunming Medical University of China on October 14 th , 2016 (approval No. 2016101411). Patient recuritment for the preliminary study was performed during January to October 2017. Patient recuritment for this study will begin in June 2018. Data collection will end in December 2020. The current study will be performed from June 2018 to December 2020. Results will be disseminated through presentations at scientific meetings and/or by publication in a peer-reviewed journal. Anonymized trial data will be published at www.figshare.com . Trial registration: This trial was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR1800015669).