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This paper presents a study of the influence on stress and deformation of the frame structure induced by double-line shield tunnels during tunneling. Using the finite element software MIDAS/GTS, the construction process of double-line shield tunnels passing through the adjacent frame structure with a strip foundation was simulated. By comparing the ground settlement monitoring data of a building passing through Changsha Metro Line 2 with the numerical simulation results, it is found that the Midas GTS/NX finite element analysis is reliable and can be used to predict the impact of shield tunneling on the frame. The location and construction sequence of double-line shield tunnels were varied to investigate the response of frame structure. The results of the analysis are as follows: (1) the position and value of the maximum stress of the frame structure are different in different excavation locations. Under the condition that the left tunnel passes under the frame structure and the right tunnel passes through from the side of the frame structure, the maximum stress of the frame structure has the minimum. (2) The frame structure inclined towards the tunnel when double-line tunnels pass-through from the side of the frame structure. Under the condition that the left tunnel passes under the frame structure and the right tunnel passes through from the side of the frame structure, the frame structure produced the longitudinal inclination. (3) The maximum settlement of the strip footings locates the ①-axis position when double-line tunnels pass-through from the side of the frame structure. The maximum settlement of the strip footings locates the ⑤-axis under the condition that the left tunnel passes under the frame structure and the right tunnel passes through from the side of the frame structure. The maximum settlement of the strip footings locates the ⑥-axis position when the double-line tunnels pass under the frame structure. (4) Under the condition that the double-line tunnels pass-through from the side of the frame structure, the impact of different construction sequences on the frame structure is slightly different. The construction sequence of the synchronous excavation of two lines in the opposite direction is more likely to cause that the frame structure inclines to the tunnel during tunneling.

Based on the similarity theory, two physical models of the double-arch tunnel with and without the damping layer are set. Through the shaking table test and numerical simulation, the damping effect of the foam concrete damping layer on the acceleration, stress, displacement and internal force of the shallow-buried bias double-arch tunnel is studied. Research indicates: (1) Foam concrete damping layer only affects the peak acceleration response and does not change the spectral characteristics of the acceleration time history curve. (2) Foam concrete damping layer reduces the principal stress peak and peak displacement of the vault and the spandrel of the double-arch tunnel to some extent. It shows that the foam concrete damping layer can improve the seismic performance of the double-arch tunnel. (3) The damping effect of foam concrete on different measuring points of double-arch tunnels is different, and the damping effects of internal forces of different properties of the same measuring point are different. In the damping design of foam concrete applied to underground projects such as double-arch tunnels, the damping effects of axial force, shear and moment should be considered separately.

Model-based polarimetric decomposition can separate to some extent the backscattered radar signals from the vegetation canopy and the underlying ground, hence enabling a strategy for soil moisture retrieval in vegetated agricultural fields. However, the volume scattering models used in previous studies are only applicable to specific cases, making it difficult to completely remove the volume component induced by the vegetation layer. In this paper, three generalized volume scattering models (i.e., generalized volume scattering model (GVSM), simplified adaptive volume scattering model (SAVSM), and simplified Neumann volume scattering model (SNVSM)) are incorporated in the decomposition and evaluated for soil moisture retrieval. Considering the complexity and descriptive ability of the available physical models, a modified two-component model-based decomposition is proposed as the basic decomposition framework. This decomposition is also based on the physical constraint of the dielectric constants included in the model. The employed models combine an X-Bragg surface scattering model with three continuous generalized volume scattering models. The analytic solution of the parameters is obtained, and the minimum power criterion is used to determine the optimal solution to fit the model. By using the proposed model-based decomposition framework, the performance of the three models to simulate the canopy scattering and, as a result, to later estimate soil moisture under agricultural vegetation is evaluated. Fully polarimetric RADARSAT-2 C-band images acquired on eight dates in 2013 and 2015 over fields covered by two crops (wheat and soybean) were employed for validation. Results show that the proposed decomposition method, using any of the three volume scattering models, can provide promising inversion results of soil moisture, with RMSEs ranging from 2.89 to 7.43 [vol.%]. Compared with the other two models, the SNVSM simulates the vegetation contribution more accurately in this framework, and it provides a stable soil moisture inversion performance at different crop phenological stages, with an optimal overall accuracy of RMSE=4.99 [vol.%] and a correlation coefficient of R=0.78. This work was supported in part by the National Natural Science Foundation of China (Grant No. 41820104005, 42171387, 41804004, 42101400), the Canadian Space Agency SOAR-E Program (Grant No. SOAR-E-5489), and the Spanish Ministry of Science and Innovation (AEI Grant No. PID2020-117303GB-C22).

This paper simulates the construction process of double-line shield tunnels crossing frame structure by using the three-dimensional finite element software MIDAS/GTS. The location and construction sequence of double-line shield tunnels were varied to investigate the influence on the ground settlement. The results show: (1) The transverse deformation curve of the ground caused by the construction of the double-line shield tunnel is symmetrical about the centerline of the tunnel. The existence of the frame structure affects ground settlement. It reflects the constraining effect of the frame structure on the formation. When the shield tunnel is excavated near the center of the frame structure, the frame structure has the greatest influence on the ground settlement. (2) The ground settlement of the center point of the strip foundation is selected as the research object. With the continuous excavation of the shield tunnel, the ground settlement curve has a slight increase. The curve drops when the shield is excavated to the frame structure. The curve levels off when the shield is excavated beyond the frame structure. It is no longer decreasing. (3) The difference in the relative position of the frame structure and the shield tunnel has a certain influence on the ground settlement. When the tunnel under-passing the frame structure, the ground settlement is minimal. (4) When the double-line shield tunnel crossing the frame structure from the side, the ground settlement caused by the reverse synchronous excavation process of the left and right lines is minimal at the center of the frame structure.

In order to reveal the acceleration response law of shallow-buried bias double-arch tunnel under earthquake. The acceleration response of the shallow-buried biased double-arch tunnel under the action of Wenchuan wave was studied by the combination of shaking table test and numerical simulation. The effects of non-bias and bias on the acceleration response of shallow-buried biased double-arch tunnels were discussed. Research indicates: (1) Horizontal acceleration amplification factor of the left-hole (non-biased side) for the shallow-buried biased double-arch tunnel is V-shaped, and the right-hole (bias side) is ∩-shaped. The vertical acceleration amplification factor of the left-hole tends to increase continuously, and the right-hole shows a trend of decreasing first and then increasing continuously. (2) In the state of both the bias and the non-biased tunnel, the acceleration response in the vertical direction is stronger than that in the horizontal direction. (3) In the two states of bias and non-bias, the difference between the horizontal and vertical acceleration amplification factors of the double-arch tunnel is larger. It indicates that the excitation direction of the seismic wave has a great influence on the acceleration response of the double-arch tunnel. (4) Relatively biased double-arch tunnels, the regularity of non-biased double-arch tunnels is better, indicating that the bias voltage has a greater impact on double-arch tunnels.

This paper deal with the problem of unmeasured premise variable(UPV) in T-S fuzzy observer for ball and beam(BAB) system. Normally,the observer design is rather challenging and with computational burden. Different from previous results to obtain the observer design condition based on a traditional T-S fuzzy model, the work here proposed a method to avoid UPV by reformulating the BAB system using the nonlinear local models in the fuzzy rules. The proposed method guarantees asymptotic convergence of state estimation. The conditions for the observer design is given in the form of linear matrix inequality(LMI) formulations. Simulation result illustrates effecitveness of the proposed method.

Background In the era of increased antibiotic resistance and ever stricter control on antibiotic use, it is urgent to develop green, safe and non-residue alternatives to antibiotics applied to the poultry industry. To this end, we supplied the potential Lactobacillus Plantarum (L. Plantarum) fermented Astragalus in the diet of laying hens, with a final addition of 3‰. Its effects have been assessed on laying performance, egg quality, antioxidant and immunological status and intestinal microbiota, and are compared to the control group, to the Astragalus group containing 3‰ unfermented Astragalus, and to the L. Plantarum group containing 2% L. Plantarum (1 × 108 CFU/mL). Results During the second half of the experimental period (15 to 28 days), the egg production rate was significantly higher in the fermented Astragalus group than that in the other groups, with the fermented Astragalus group having the lowest feed conversion ratio. No significant difference (P > 0.05) was observed among treatments on egg quality. Fermented Astragalus-treated hens exhibited significantly increased catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in serum, and reduced malondialdehyde (MDA) in serum. Furthermore, fermented Astragalus supplementation resulted in a significant increase in ileal microbiota abundance relative to control. Conclusions Feeding laying hens with L. Plantarum fermented Astragalus has beneficial effects on production, antioxidant potential, immunity and ileal microbiota. L. Plantarum fermented Astragalus is expected to be a novel feed additive used in poultry production.

Astragalus of traditional Chinese medicine (TCM) and Bacillus subtilis are extensively used in animal feed and for production of various fermented compounds. In order to observe the characteristics of HNMY-13 and HNMY-15 B. subtilis strains, this study focused on the optimization of parameters in liquid fermentation of the two strains in aflatoxin B1 degradation, and Astragalus polysaccharide yield. The optimal parameters: degradation of aflatoxin B1, the bacterial count, and the Astragalus polysaccharide yield analysis were examined in this study. It was shown that the percentage degradation of AFB1 by HNMY-13 and HNMY-15 strains were 80.48 and 79.55% at 37°C, and 80.66% and 81.34 with pH 7.0. The percentage degradation by HNMY-13 was 88.07% after 48 h fermentation and by HNMY-15 was 84.81% after 60 h fermentation, respectively. The viable count of fermented sample was 8.8×108 and 7.6×108 CFU·mL-1 using HNMY-13 and HNMY-15 strains, respectively. The polysaccharide yielded by HNMY-13 was 4.93% at 48 h which is 1.7-fold higher than that of the control group, while polysaccharide yielded by HNMY-15 reached peak of 3.54% at 60 h. In conclusion, HNMY-13 and HNMY-15 of B. subtilis promote production of Astragalus polysaccharide in the process of liquid fermentation and can also degrade aflatoxin B1 significantly; hence the combination could form a potential feed additive for animals. Key words: Astragalus, Bacillus subtilis, liquid fermentation, aflatoxin B1, polysaccharide.

This paper deal with an SOS based stability analysis of the polynomial fuzzy model based (PFMB) control systems. By applying the Euler’s homogeneity relation, the homogeneous Lyapunov function is introduced and a novel stability condition is presented. To verify the analytical theories with the proposed method, a popular example is employed to show the effectiveness of the proposed stability condition.

This paper is concerned with blood glucose control problem for type-1 diabetes whose nonlinear dynamics are explained in the Takagi-Sugeno (T-S) fuzzy model. The proposed T-S fuzzy control method is derived based on quadratic Lyapunov function aiming at attenuating the error as small as possiblin in the H ∞ performance sense. Conditions for the solvability of the H ∞ controller design given here are written in the form of linear matrix inequalities which are easier to be solved by convex optimization techniques. Simulation example is given to demonstrate the validity and applicability of the proposed approaches.

This paper presents the design and simulation results considering the use of polynomial fuzzy control for stabilization of multi-scroll Chen chaotic system. The chaotic system is represented in the polynomial fuzzy model form and less conservation stability conditions are proposed. The controller here designed is obtained by solving the sum-of-squares constraints via SOSTOOLS. Simulation results show the effectiveness of the proposed controller design method.

The composition and function of the intestinal microbiota play important roles in digestion and degradation of herbal medicines (HMs). However, few studies have examined the relationship between the fecal microbiota and HMs. In this study the effect of unfermented Astragalus (UA) and fermented Astragalus (FA) on growth performance, serum biochemical parameters, and fecal microbiota was evaluated in broiler chickens. In total, 180 one-day-old broiler chickens (Avian breeds) were randomly assigned to a control (C) group fed a basal diet, an unfermented (U) group fed a basal diet containing 0.5% UA, or a fermented (F) group fed a basal diet containing 0.5% FA, for 42 days. The F/G ratio was lower in F and U groups than in C group from 22 to 42 days (P

In this paper, terminal sliding mode control is used to study the finite-time stabilization of unified chaotic system. A new controller is proposed by designing a non-singular terminal sliding mode surface and using the power approaching law. Sliding mode surface arrival time and system stabilization time is analyzed. Simulation results show that the proposed method can achieve effective control of the unified chaotic system with a single control input even if the system parameters change continuously.

We investigated if fermentation with probiotic cultures could improve the production of health-promoting biological compounds in Astragalus membranaceus. We tested the probiotics Enterococcus faecium, Lactobacillus plantarum and Enterococcus faecium + Lactobacillus plantarum and applied PacBio single molecule, real-time sequencing technology (SMRT) to evaluate the quality of Astragalus fermentation. We found that the production rates of acetic acid, methylacetic acid, aethyl acetic acid and lactic acid using E. faecium + L. plantarum were 1866.24 mg/kg on day 15, 203.80 mg/kg on day 30, 996.04 mg/kg on day 15, and 3081.99 mg/kg on day 20, respectively. Other production rates were: polysaccharides, 9.43%, 8.51%, and 7.59% on day 10; saponins, 19.6912 mg/g, 21.6630 mg/g and 20.2084 mg/g on day 15; and flavonoids, 1.9032 mg/g, 2.0835 mg/g, and 1.7086 mg/g on day 20 using E. faecium, L. plantarum and E. faecium + L. plantarum, respectively. SMRT was used to analyze microbial composition, and we found that E. faecium and L. plantarum were the most prevalent species after fermentation for 3 days. E. faecium + L. plantarum gave more positive effects than single strains in the Astragalus solid state fermentation process. Our data demonstrated that the SMRT sequencing platform is applicable to quality assessment of Astragalus fermentation.

Background. Astragalus was a well-known traditional herbal medicine, widely used in human s , livestock and poultry in China and E ast Asia. Fermentation could improve health-promoting biological substance by probiotics. Methods. We investigated Astragalus that was fermented using probiotics including Enterococcus faecium , Lactobacillus plantarum and E nterococcus faecium + L actobacillus plantarum and applied the PacBio single molecule, real-time sequencing technology (SMRT) to evaluat e the quality of Astragalus fermentation production. Results. We found the production rates of acetic acid, methylacetic acid , ethylacetic acid and lactic acid using E. faecium + L. plantarum fermentation were 1866.24 mg/kg on day 15 , 203.80 mg/kg on day 30 , 996.04 mg/kg on day 15 and 3081.99 mg/kg on day 20 , respectively. Other production rates were: polysaccharide s, 9.43%, 8.51% and 7 . 59% on day 10; saponins , 19.6912 mg/g, 21.6630 mg/g and 20.2084 mg/g on day 15; and flavonoid s, 1.9032 mg/g, 2.0835 mg/g and 1.7086 mg/g on day 20 using E . faecium , L . plantarum and E. faecium + L. plantarum , respectively. According to SMRT analysis of the microbial composition s of nine Astragalus samples, we found after fermentation on day 3 , E. faecium and L. plantarum became the most prevalent species. Moreover, E. faecium + L. plantarum gave more positive effects than single strains in the Astragalus solid state fermentation process. Inclusion. Our data have demonstrate d that the SMRT sequencing platform is applicable to assessing the quality of Astragalus fermentation.

Harmonic impedance of system is the important parameter for the harmonic suppression and it is also useful to the design of filter, circuit analysis, et al. Generally, a controllable harmonic perturbation is used and injected into the target circuit port, and then harmonic impedance can be captured by the corresponding harmonic voltage and current. In this paper, a circuit design of harmonic impedance measurement is proposed, in which each functional modules is comprised of analogue circuit, and it can generate a controllable current disturbance into the target system. The system impedance is calculated by using the current and the corresponding voltage, which are captured by the data acquisition circuits. By using the PSCAD, a simulation of measurement circuit is established. In simulation, the measuring results are coincident with the theoretical value, which validate the effectiveness of the circuit design.

Uncontrolled Rectifier is widely applied in power supply, HVDC, et al, which could be regarded as the typical nonlinear device in power system. It injects a mass of harmonic current into power system and dramatically leads to voltage distortion. The relationship between the harmonic voltage and current, namely called input impedance, is nonlinear. Conversional system voltage control is based on the harmonic currents compensation. However, the harmonic currents changes with the voltage control, namely the harmonic currents compensation reference are shifty in real time, which degrade voltage control performance. Therefore, it is necessary to analysis the impedance character of nonlinear loads, and applies it to the control system to realize the harmonic current dynamic compensation and improve the voltage control performance. In this paper, a time domain input impedance model for uncontrolled rectifier is developed, and then the nonlinear character of the input impedance is analyzed. Finally, a simulation model is implemented, the simulation results validate the theoretical analysis.

Wireless Sensor Networks (WSNs) are networks of autonomous nodes used for monitoring an environment, and clustering is one of the most popular and effective approach for WSNs that require scalability and robustness. In this paper, we propose and analyze an Adaptive Node Partition Clustering protocol using Particle Swarm Optimization (ANPC-PSO), a protocol that partitions the network field adaptively and selects cluster heads (CHs) consider the networks states information. The results of performance evaluation show that ANPC-PSO can improve system lifetime and data delivery by distributing energy dissipation evenly in the networks.

Electrical and optical properties of InGaN/AlGaN double heterostructure blue light-emitting diodes were investigated. Measurement of the forward bias current-voltage behaviour of the device demonstrated a departure from the Shockley model of a p-n diode, and it was observed that the dominant mechanism of carrier transport across the junction is associated with carrier tunnelling. Electroluminescence experiments indicated that there was a main emission band around 2.80 eV and a relatively weaker peak at 3.2 eV. A significant blueshift of the optical emission band was observed, which was consistent with the tunnelling character of electrical characteristics. Furthermore, the degradation in I-V characteristics and the low resistance ohmic short of the device were observed.

We report the current-induced light emission (CILE) at RT from a porous silicon (PS) Schottky device exhibiting good rectifying characteristics with the ideal factor of 14. The photoluminescence spectrum from the PS layer fabricated by laterally anodization peaks at 688 nm. The intensity of CILE increases with increasing current. It has run for more than two hours and still keeps stable. Possible mechanism of CILE is discussed.

In this paper, we will report fabrication and structure study of single crystal β-SiC film on Si substrate by hot-filament chemical vapor deposition (HFC VD). The reaction sources are hydrogen-diluted methane(CH4) and Silane(SiH4). The wafer surface temperature is about 650°C. The typical growth rate is 200nm/h. Raman scattering spectrum shows a peak centering at 960cm-1 with a full width at half magnitude (FWHM) of 75cm-1. At room temperature, the photoluminescence spectrum gives a wide band at 580nm (2.2eV) with a FWHM of 55nm. Fourier transmission infrared (FT-IR) spectrum exhibits an absorption peak at 12.6 μm XRD and XPS analysis indicate that the epilayer is a stoichiometrical single crystal cubic silicon carbide film.