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A high resolution range profile (HRRP) is a summation vector of the sub-echoes of the target scattering points acquired by a wide-band radar. Generally, HRRPs obtained in a non-cooperative complex electromagnetic environment are contaminated by strong noise. Effective pre-processing of the HRRP data can greatly improve the accuracy of target recognition. In this paper, a denoising and reconstruction method for HRRP is proposed based on a Modified Sparse Auto-Encoder, which is a representative non-linear model. To better reconstruct the HRRP, a sparse constraint is added to the proposed model and the sparse coefficient is calculated based on the intrinsic dimension of HRRP. The denoising of the HRRP is performed by adding random noise to the input HRRP data during the training process and fine-tuning the weight matrix through singular-value decomposition. The results of simulations showed that the proposed method can both reconstruct the signal with fidelity and suppress noise effectively, significantly outperforming other methods, especially in low Signal-to-Noise Ratio conditions.

Large and high-dimensional real-world datasets are being gathered across a wide range of application disciplines to enable data-driven decision making. Interactive data visualization can play a critical role in allowing domain experts to select and analyze data from these large collections. However, there is a critical mismatch between the very large number of dimensions in complex real-world datasets and the much smaller number of dimensions that can be concurrently visualized using modern techniques. This gap in dimensionality can result in high levels of selection bias that go unnoticed by users. The bias can in turn threaten the very validity of any subsequent insights. This article describes Adaptive Contextualization (AC), a novel approach to interactive visual data selection that is specifically designed to combat the invisible introduction of selection bias. The AC approach (1) monitors and models a user’s visual data selection activity, (2) computes metrics over that model to quantify the amount of selection bias after each step, (3) visualizes the metric results, and (4) provides interactive tools that help users assess and avoid bias-related problems. This article expands on an earlier article presented at ACM IUI 2016 [16] by providing a more detailed review of the AC methodology and additional evaluation results.

The rheo-squeeze casting (RSC) process is a newly-developed casting process for high-performance components. In order to further improve the mechanical properties of magnesium alloys, AZ91-2wt.%Ca (AZX912) alloy was prepared by the RSC process and then subjected to heat treatment. The microstructure evolution and mechanical properties of AZX912 alloy during heat treatment were investigated. It was found that during solid solution treatment at 410 °C, β-Mg17Al12phase with low melting point dissolves into α-Mg matrix, while the connected network-like Al2Ca phase with high melting point tends to separate gradually, and the tips of Al2Ca phase is partially spheroidized. With the increase of solid solution time, the yield strength (YS) of AZX912 alloy decreases gradually while the ultimate tensile strength (UTS) and elongation to failure (Ef) increase continuously. Isothermal ageing at 225 °C promotes the precipitation of β-Mg17Al12phase in the matrix of AZX912 alloy. The hardness reaches the peak after ageing for 96 h and the increase in hardness is about 24.8%. The precipitation of β-Mg17Al12phase during ageing treatment is beneficial to YS but harmful to Ef. The mechanism of microstructure evolution during heat treatment and its effect on mechanical properties are discussed.

Trajectory data mining is widely used in military and civil applications, such as early warning and surveillance system, intelligent traffic system and so on. Through trajectory similarity measurement and clustering, target behavior patterns can be found from massive spatiotemporal trajectory data. In order to mine frequent behaviors of targets from complex historical trajectory data, a behavior pattern mining algorithm based on spatiotemporal trajectory multidimensional information fusion is proposed in this paper. Firstly, spatial–temporal Hausdorff distance is proposed to measure multidimensional information differences of spatiotemporal trajectories, which can distinguish the behaviors with similar location but different course and velocity. On this basis, by combining the idea of k-nearest neighbor and density peak clustering, a new trajectory clustering algorithm is proposed to mine behavior patterns from trajectory data with uneven density distribution. Finally, we implement the proposed algorithm in simulated and radar measured trajectory data respectively. The experimental results show that the proposed algorithm can mine target behavior patterns from different complex application scenarios more quickly and accurately compared to the existing methods, which has a good application prospect in intelligent monitoring tasks.

Background: Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disease caused by a polyglutamine expansion in the ataxin-1 protein. The pathogenic mechanism resulting in SCA1 is still unclear. Protein–protein interactions affect the function and stability of ataxin-1. Methods: Wild-type and mutant ataxin-1 were expressed in HEK-293T cells. The levels of expression were assessed using real-time polymerase chain reaction (PCR) and Western blots. Co-immunoprecipitation was done in HEK-293T cells expressing exogenous wild-type and mutant ataxin-1 using anti-Flag antibody following by tandem affinity purification in order to study protein–protein interactions. The candidate interacting proteins were validated by immunoprecipitation. Chromatin immunoprecipitation and high-throughput sequencing and RNA immunoprecipitation and high-throughput sequencing were performed using HEK-293T cells expressing wild-type or mutant ataxin-1. Results: In this study using HEK-293T cells, we found that wild-type ataxin-1 interacted with MCM2, GNAS, and TMEM206, while mutant ataxin-1 lost its interaction with MCM2, GNAS, and TMEM206. Two ataxin-1 binding targets containing the core GGAG or AAAT were identified in HEK-293T cells using ChIP-seq. Gene Ontology analysis of the top ataxin-1 binding genes identified SLC6A15, NTF3, KCNC3, and DNAJC6as functional genes in neurons in vitro. Ataxin-1 also was identified as an RNA-binding protein in HEK-293T cells using RIP-seq, but the polyglutamine expansion in the ataxin-1 had no direct effects on the RNA-binding activity of ataxin-1. Conclusions: An expanded polyglutamine tract in ataxin-1 might interfere with protein–protein or protein–DNA interactions but had little effect on protein–RNA interactions. This study suggested that the dysfunction of protein–protein or protein–DNA interactions is involved in the pathogenesis of SCA1.

To analyze the serum levels of miR-126, miR-146a and its relationship with infarction area, severity of disease and inflammatory reaction degree in patients with acute cerebral infarction (ACI).

A kind of nonwoven containing ferulic acid is prepared by electrospinning method. It was observed that the diameter of the fiber was about 200 nm by SEM. The antibacterial activities against Escherichia coli and S. aureus were also investigated. The result showed the nonwoven prepared was effective against Escherichia coli, and S. aureus. Furthermore, Fabric UV transmittance test and air permeability were taken. It was found that the nonwoven achieved good UV protection and air permeability.

A twin annular premixing swirler (TAPS) combustor model of low emissions was developed in this study. And computational studies on combustion process in the combustor model were carried out. Standard k-ε Turbulence Model, PDF non-premixed combustion model, Zeldovich thermal NOx formation model and DPM two-phase model were employed. The distributions of some key performance parameters such as gas temperature, flow velocity, concentrations of NOx and CO emissions were obtained and analyzed. At the same time, combustion mechanics inside the TAPS combustor model were investigated. The computational results indicated that the TAPS combustor employed in this study does a better job of improving key combustion performances such as combustion efficiency, total pressure recovery and outlet temperature distribution factor, and reducing NOx and CO emissions at the same time.

A calculation method on pollutant emission inventory is established based on the standard LTO cycle of the International Civil Aviation Organization (ICAO) by analyzing the factors influencing aircraft engine emissions at civil aviation airports. For a certain airport in China, the emissions of HC, CO, NOx and SO2 per hour for a whole day from the aircraft engines are calculated, and the variations of various pollutant emissions with time are analyzed based on the air traffic data, the civil aviation fleet composition, the flight detailed take-off and landing information at the airport, and ICAO engine emission data bank. It’s found that the variations of the pollutant emissions with time are different, in which, the emissions of HC and CO are significantly influenced by the frequency of flight arrival at airport, however, the emission of NOx is influenced by the frequency of flight departure from airport greatly, and the emission of SO2 is influenced by the total frequency of flight arrival at and departure from airport comprehensively. For solving the problem of local high-emission time, some solutions are suggested, such as equipping aircrafts with low-emission engines or optimizing the flight schedule.

Aiming at the problem that the temperature measurement is backward in wine solid-state fermentation. In this paper, a wireless temperature-measuring system for monitoring the change of fermentation temperature describes the detailed analysis of the system architecture, hardware and software. The system based on low-power microprocessor STM8L, with SI4463 as wireless communication module, and LABVIEW as development platform. The system ensures its accuracy by method of least squares piecewise fitting the relation between PT100 resistance and temperature. The nodes use hopping mechanism, periodic sleep and wake-on-radio mechanism to make communication path for the MAC layer stable and decrease the power consumption. The system has a stable performance and has achieved good results in practical application.

The rotor and stator were major components of the opposed biconinal cone screw high pressure seawater hydraulic pump, which precision of design and manufacture was particularly high, and the combining status between the stator and rotor has a significant impact on the performance of the new type pump, so the related research on above problems are carried out. In order to satisfy the demands of design efficiency and manufacture decision, a fast and simple way was presented to model 3D cone screw and bushing. Three-dimensional space Cartesian coordinates of cone screw and bushing profile with MATLAB programming were obtained according to the cone screw and bushing surface equation and the design parameters,3D curves of cone screw and bushing with MATLAB were rendered, and the feature point space coordinates were imported to Pro/Engineer so as to build cone screw and bushing solid model. Finally, making virtual assembly and checking interference on the screw and the bushing were necessary. The proposed method can make the complex 3D modeling more accurate, feasible and efficient.

Studies of threading dislocations with Burgers vector of c+a have been carried out using synchrotron white beam X-ray topography. The nucleation and propagation of pairs of opposite sign threading c+a dislocations is observed. Overgrowth of inclusions by growth steps leads to lattice closure failure and the stresses associated with this can be relaxed by the nucleation of opposite sign pairs of dislocations with Burgers vector c+a. Once these dislocations are nucleated they propagate along the c-axis growth direction, or can be deflected onto the basal plane by overgrowth of macrosteps. For the c+a dislocations, partial deflection can occasionally occur, e.g. the a-component deflects onto basal plane while the c-component continuously propagates along the growth direction. One factor controlling the details of these deflection processes is suggested to be related to the ratio between the height of the overgrowing macrostep and that of the surface spiral hillock associated with the threading growth dislocations with c-component of Burgers vector.

In order to reasonably make good use of solar energy---a kind of typical and clean energy, especially increase the efficiency of solar energy usage in town buildings, this paper introduces and analyzes solar Thermal-arrest Technology by way of how to increase solar absorption efficiency and how to decrease collector heat loss, finds an effective way to increase the efficiency of present solar collectors. Solar Thermal-arrest Technology is good for being widely used in town buildings. Its reasonable development is helpful to reducing building energy consumption and the relief of present energy shortage in China.

A review is presented of Synchrotron White Beam X-ray Topography (SWBXT) studies of stacking faults observed in PVT-Grown 4H-SiC crystals. A detailed analysis of various interesting phenomena were performed and one such observation is the deflection of threading dislocations with Burgers vector c/c+a onto the basal plane and associated stacking faults. Based on the model involving macrostep overgrowth of surface outcrops of threading dislocations, SWBXT image contrast studies of these stacking faults on different reflections and comparison with calculated phase shits for postulated fault vectors, has revealed faults to be of basically four types: (a) Frank faults; (b) Shockley faults; (c) Combined Shockley + Frank faults with fault vector s+c/2; (d) Combined Shockley + Frank faults with fault vector s+c/4.

A deformation-processed Cu-10Fe-3Ag in situ composite was made by consumable arc melting and casting followed by extensive deformation. A superior combination of mechanical strength and electrical/thermal conductivity was achieved with the composite since Fe filaments existed in the copper matrix. The effects of sliding speed and electrical current on sliding wear behavior and microstructure of the composite were investigated on wear tester. Worn surfaces of the Cu-10Fe-3Ag in situ composite were analyzed by scanning electron microscopy (SEM). Within the studied range of electrical current and sliding speed, the wear rate increased with the increasing electrical current and the sliding speed. Compared with Cu-10Fe in situ composite under the same conditions, the Cu-10Fe-3Ag in situ composite had much better wear resistance. Adhesive wear, abrasive wear and arc erosion were the dominant mechanisms during the electrical sliding processes.

A Cu–10Fe–3Ag alloy was produced by means of induction melting. The effects of aging processes on microhardness and conductivity of Cu–10Fe–3Ag alloy were studied. The microstructure of the alloy was examined using transmission electron microscope (TEM). The results show that: presence of Ag can accelerate γ-Fe precipitation from in the Cu matrix, but also reduces the thermal stability of Fe fibers. As the annealing temperature increasing, the microhardness and conductivity of Cu-10Fe-3Ag in-situ composite increase at first and then decrease. Annealed at 475 for 6h, the alloy has an excellent combination of microhardness and conductivity, the microhardness and conductivity reach 209HV and 58.4% IACS, respectively. The Fractures of the alloy are all ductile rupture and the dimples are smaller with the annealing temperature increasing.

In this paper, the reliability of contactor relay is studied. There are three main parts about reliability test and analysis. First, in order to analyze reliability level of contact relay, the failure ratio ranks are established as index base on the product level. Second, the reliability test method is put forward. The sample plan of reliability compliance test is gained from reliability sample theory. The failure criterion is ensured according to the failure modes of contactor relay. Third, after reliability test experiment, the analysis of failure physics is made and the failure reason is found.

The purpose of this investigation is to determine the extent to which Luecking's decomposition of Bergman spaces $ \mathcal{L}_a^p,(1 < p < \infty )$ $ \mathcal{L}_a^1$ . In this note we equip each of such functions with a new norm and study the resulting Banach space. We describe its dual and predual.

It is shown that the Bourgain algebra $ {X_b}$ $ X = {H^\infty }$ $ \mathcal{U} = \operatorname{alg} \{ {H^\infty },{\overline H ^\infty }\} $ $ {H^\infty }(\mathbb{D}) + UC(\mathbb{D})$ $ UC(\mathbb{D})$ $ \mathbb{D}$ $ {H^\infty }$ $ \partial \mathbb{D}$ .

Quadratic cost optimal controls can be solved by penalizing the governing linear differential equation [2], [9]. In this paper, we study the numerical analysis of this approach using finite elements. We formulate the geometric condition (H) which requires that pairs of certain related finite-dimensional approximation spaces form "angles" which are bounded away from the "180$ ^\circ$ $ \varepsilon $h are independent in the error bounds, thereby giving sharp asymptotic error estimates. This condition (H) is shown to be also a necessary condition for such independence. Examples and numerical evidence are also provided.