Photon-assisted Fano Resonance and Corresponding Shot-Noise in a Quantum Dot

We have studied the Fano resonance in photon-assisted transport in a quantum dot and calculated both the coherent current and spectral density of shot noise. It is predicted, for the first time, that the shape of Fano profile will also appear in satellite peaks. It is found that the variations of Fano profiles with the strengths of nonresonant transmissions are not synchronous in absorption and emission sidebands. The effect of interference on photon-assisted pumped current has been also investigated. We further predict the current and spectral density of shot noise as a function of the phase, which exhibits an intrinsic property of resonant and nonresonant channels in the structures.Comment: 4 pages, 5 figure

Model Aerodynamic Tests with a Wire-driven Parallel Suspension System in Low-speed Wind Tunnel

AbstractOwing to the advantages of wire-driven parallel manipulator, a new wire-driven parallel suspension system for airplane model in low-speed wind tunnel is constructed, and the methods to measure and calculate the aerodynamic parameters of the airplane model are studied. In detail, a static model of the wire-driven parallel suspension is analyzed, a mathematical model for describing the aerodynamic loads exerted on the scale model is constructed and a calculation method for obtaining the aerodynamic parameters of the model by measuring the tension of wires is presented. Moreover, the measurement system for wire tension and its corresponding data acquisition system are designed and built. Thereafter, the wire-driven parallel suspension system is placed in an open return circuit low-speed wind tunnel for wind tunnel tests to acquire data of each wire tension when the airplane model is at different attitudes and different wind speeds. A group of curves about the parameters for aerodynamic load exerted on the airplane model are obtained at different wind speeds after the acquired data are analyzed. The research results validate the feasibility of using a wire-driven parallel manipulator as the suspension system for low-speed wind tunnel tests

A Spatio-temporal Decomposition Method for the Coordinated Economic Dispatch of Integrated Transmission and Distribution Grids

With numerous distributed energy resources (DERs) integrated into the distribution networks (DNs), the coordinated economic dispatch (C-ED) is essential for the integrated transmission and distribution grids. For large scale power grids, the centralized C-ED meets high computational burden and information privacy issues. To tackle these issues, this paper proposes a spatio-temporal decomposition algorithm to solve the C-ED in a distributed and parallel manner. In the temporal dimension, the multi-period economic dispatch (ED) of transmission grid (TG) is decomposed to several subproblems by introducing auxiliary variables and overlapping time intervals to deal with the temporal coupling constraints. Besides, an accelerated alternative direction method of multipliers (A-ADMM) based temporal decomposition algorithm with the warm-start strategy, is developed to solve the ED subproblems of TG in parallel. In the spatial dimension, a multi-parametric programming projection based spatial decomposition algorithm is developed to coordinate the ED problems of TG and DNs in a distributed manner. To further improve the convergence performance of the spatial decomposition algorithm, the aggregate equivalence approach is used for determining the feasible range of boundary variables of TG and DNs. Moreover, we prove that the proposed spatio-temporal decomposition method can obtain the optimal solution for bilevel convex optimization problems with continuously differentiable objectives and constraints. Numerical tests are conducted on three systems with different scales, demonstrating the high computational efficiency and scalability of the proposed spatio-temporal decomposition method

Wideband Inverse Matrix For Radiated Two-Stage MIMO Measurements

Multiple-input and multiple-output (MIMO) technology is one of the significant components in the growing fifth-generation (5G) communication systems. The 5G system has expanded its frequency range and widened the bandwidth to achieve higher throughput rates and more stable wireless qualities, which brings new challenges to the over-the-air (OTA) MIMO evaluations. The wide bandwidth introduces systematic uncertainties into the MIMO measurement because of the increased amplitude and phase variation issues under different frequencies in the wideband signals, and it could lead to invalid MIMO throughput measurement results when severe. The effect on antenna isolation resulting from amplitude and phase variation in wideband MIMO measurements are analyzed based on the RTS MIMO measurement method. A wideband inverse matrix algorithm is introduced to solve this issue and improve the wideband MIMO antenna isolation. The proposed method can be used in both MPAC and RTS chambers, which paves the way for decreasing the OTA measurement uncertainties on both 5G sub-6GHz wideband MIMO and millimeter-wave MIMO evaluations

Alpha-fetoprotein level as a biomarker of liver fibrosis status: a cross-sectional study of 619 consecutive patients with chronic hepatitis B

BACKGROUND: Hepatitis B virus (HBV) infection is a serious public health problem worldwide. This study aimed to investigate the relationship between serum alpha-fetoprotein (AFP) levels and pathological stages of liver biopsy in patients with chronic hepatitis B (CHB). METHODS: The study included 619 patients who were diagnosed with CHB from March 2005 to December 2011. AFP levels were measured by electrochemiluminescence. Liver biopsy samples were classified into five levels of inflammation (G) and fibrosis (S) stages, according to the Chinese guidelines for prevention and treatment of viral hepatitis. Two multivariable ordinal regression models were performed to determine associations between AFP, GGT, and APRI (AST/PLT ratio) and stages of inflammation and fibrosis. RESULTS: Significant positive and moderate correlations were shown between AFP levels and inflammation stages and between AFP levels and fibrosis stages (ρ = 0.436 and 0.404, p < 0.001). Median values of AFP at liver fibrosis stages S0-1, S2, S3, and S4 were 3.0, 3.4, 5.4, and 11.3 ng/ml, respectively, and median APRI (AST/PLT ratio) was 0.41. Receiver operating characteristic (ROC) curve analyses revealed that the areas under the curves (AUCs) were 0.685, 0.727, and 0.755 (all p <0.001) for judging inflammation stages of G ≥ 2, G ≥ 3, G = 4 by AFP; and 0.691, 0.717, and 0.718 (all p <0.001) for judging fibrosis stages of S ≥ 2, S ≥ 3, and S = 4 by AFP. APRI levels showed significant positive and moderate correlations with inflammation stages (ρ = 0.445, p < 0.001). AST, GGT, and APRI levels showed significant positive but very weak to weak correlations with fibrosis stages (ρ = 0.137, 0.237, 0.281, p < 0.001). CONCLUSIONS: Serum AFP levels increased as pathological levels of inflammation and fibrosis increased in CHB patients. Our data showed the clinical significance of serum AFP levels in diagnosing liver inflammation and fibrosis. Assessment of liver pathology may be improved by creating a predictive mathematical model by which AFP levels with other biomarkers

Tensile flow stress of non-oriented Fe-3.3%Si steel at a wide range of moderate temperatures

The flow stress behavior of hot-rolled Fe-3.3%Si steel was studied through single-pass warm tensile&nbsp;experiments within the temperature range of 250 to 700 °C and strain rate range of 0.001 s-1 to 0.1 s-1. The peak&nbsp;stress decreased linearly, but the elongation increased exponentially, with an increase in temperature. Work&nbsp;hardening behavior was obvious, and the non-uniform plastic deformation stage was shorter at lower&nbsp;temperatures, and accordingly the grains were elongated. A novel method was proposed to describe the tensile&nbsp;flow stress of Fe-3.3%Si steel at wide moderate temperatures, and the flow behavior of Fe-3.3%Si was described&nbsp;as the function of temperature, strain and strain rate. The capability of the model to predict tensile flow stress&nbsp;was investigated and the predicted results were in good agreement with measured values. Therefore, the model is&nbsp;reliable and helpful for the optimization of deformation parameters in warm processing

Transcriptome Analysis of Metapenaeus affinis Reveals Genes Involved in Gonadal Development

Metapenaeus affinis is a crustacean with important commercial value in the fishery of the South China Sea. Overfishing has resulted in the decline of the wild population and germplasm degradation. However, there is little background knowledge about its gonadal development, and there is a lack of research on the development of this species. To better understand the molecular regulatory mechanisms during gonadal development, here, we performed RNA-Seq on immature and mature ovaries and compared their transcriptomic signatures. 126,930,488 and 122,677,356 clean sequencing reads were obtained from the Illumina sequencing platform, respectively. 394 differentially expressed genes (DEGs) were identified, of which 136 were up-regulated, and 258 were down-regulated. Further analysis revealed rich transcriptional sequences, which have homology with genes related to reproduction and development. Expression patterns of COX, GPX, E3s, PCNA, STPK, and other genes were changed during ovarian development. Validation by qRT-PCR demonstrated the reliability of RNA-Seq. This study has made a significant contribution to the currently available sequence data of M. affinis and provided reference data for the development of genetic and breeding work

Optimization for Variable Height Wind Farm Layout Model

The optimization of wind farm layouts is very important for the effective utilization of wind resources. A fixed wind turbine hub height in the layout of wind farms leads to a low wind energy utilization and a higher LCOE (levelized cost of electricity). WOMH (Wind Farm Layout Optimization Model Considering Multiple Hub Heights) is proposed in this paper to tackle the above problem. This model is different from the traditional fixed hub height model, as it uses a variable height wind turbine. In WOMH, the Jensen wake and Weibull distribution are used to describe the wake effect on the wind turbines and wind speed distribution, respectively. An algorithm called DEGM (differential evolution and greedy method with multiple strategies) is proposed to solve WOMH, which is NP hard. In the DEGM, seven strategies are designed to adjust the distribution coordinates of wind turbines so that the height of the wind turbines will be arranged from low to high in the wind direction. This layout reduces the Jensen wake effect, thus reducing the value of the LCOE. The experimental results show that in the DEGM, when the number of wind turbines is 5, 10, 20, 30 and 50, the WOMH reduces the LCOE by 13.96%, 12.54%, 8.22%, 6.14% and 7.77% compared with the fixed hub height model, respectively. In addition, the quality of the solution of the DEGM is more satisfactory than that of the three-dimensional greedy algorithm and the DEEM (differential evolution with a new encoding mechanism) algorithm. In the case of five different numbers of wind turbines, the LCOE of DEGM is at least 3.67% lower than that of DEEM, and an average of 6.83% lower than that of three-dimensional greedy. The model and algorithm in this paper provide an effective solution for the field of wind farm layout optimization