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The TianQin Project is aiming at gravitational wave (GW) detection in space. TianQin GW observatory comprises three satellites orbiting on 1 × 105 km Earth orbits to form an equilateral-triangle constellation. In order to minimize the variations in arm lengths and breathing angles, the satellites must be launched and adjusted precisely into an optimized orbit. Therefore, satellite laser ranging must be used to enhance the precision of satellite orbit determination. To develop the capability of satellite laser ranging for TianQin’s orbit, the TianQin Laser Ranging Station has been designed and constructed to perform high-precision laser ranging for TianQin satellites and lunar laser ranging as well. Applying a 1064 nm Nd: YAG laser with 100 Hz repetition frequency, 80 pico-second pulse duration, and 2 × 2 array of superconducting nanowire single-photon detectors, we have obtained the laser echo signals from the five lunar retro-reflector arrays, and the measurement data have been packaged into 234 normal points (NPs), including a few data measured during the full-moon lunar phase. Each NP is calculated from continuous measurement for about ten minutes and the statistical error of the NPs is about 7 mm (1σ).

Performance of boron-based solid rocket ramjet was carried out by the ground direct connection test rig. Through SEM and EDS analysis of condensed products on the insulation wall of the second combustion chamber, the change of carbonization structure of insulation and the deposition of condensed particles along the axis were researched. Experiment results show that porosity of the carbonized layer become larger and the structure becomes loose along flow direction. The deposition of condensed particles on the insulation wall is increased, and the deposition is obvious at nozzle entrance.

As the signal reflected by the corner-cube reflector arrays is very weak and easily submerged during the full moon, we analyze the influence of the thermal effect of corner-cube reflector arrays on the intensity of lunar laser ranging echo. Laser ranging measurements during the penumbra lunar eclipse verify suspected thermal deformation in the Lunakhod 2 reflectors. Signal levels vary over two orders of magnitude as the penumbra eclipse progresses. This can be explained by the change in the dihedral angle of the corner-cube reflectors caused by the temperature. The results show that when the dihedral angle errors reach 1″, the energy is reduced by 100 times compared with the ideal corner-cube reflector. In the experiment, our findings suggest that when the corner-cube reflector arrays enter the penumbra of the earth, the effective echo signal level which reaches 0.18 photons/s far exceeds the historical level of the full moon. However, 11 minutes after the penumbra lunar eclipse, the effective echo rate of Lunakhod 2 will drop two orders of magnitude. The mechanism can explain the acute signal deficit observed at full moon.

Ultra high-strength M54 steel blocks were fabricated by laser metal deposition. The microstructure and mechanical behavior of the material were investigated systematically. The microstructure of the as-deposited M54 steel is anisotropic; the cross-section (XOY plane) has a cellular structure, whereas the longitudinal section (XOZ and YOZ planes) shows a mixture of alternating cellular and columnar forms. Compositional segregation is present at the cell walls (interdendritic regions) in the as-deposited state, resulting in retained austenite at the cell walls. The cross-sectional XOY plane contains 10.08% austenite, whereas the XOZ and YOZ planes contain 24.59% and 22.4% austenite, respectively. The retained austenite at the cell wall (interdendritic region) has low thermal and mechanical stability and disappears after the cryogenic treatment or is transformed into martensite during a tensile test. The as-deposited samples show anisotropic mechanical properties. The transverse samples exhibit stronger transformation-induced plasticity (TRIP) and work hardenability with a lower yield strength of 662 MPa and higher ultimate strength of 1982 MPa, corresponding to a higher amount of retained austenite in this direction. The longitudinal ultimate strength and yield strength are 1832 MPa and 997 MPa, respectively. The ductility and toughness are also largely anisotropic, and their reduction in the transverse direction is only 1/3 of that in the longitudinal direction. The Vickers hardness of the microstructure increases slightly from the bottom to the middle and upper part of the sample due to less thermal cycling in the upper part.

The utilization of solar energy to drive energy conversion and simultaneously realize pollutant degradation via photocatalysis is one of most promising strategies to resolve the global energy and environment issues. During the past decade, graphite carbon nitride (g-C3N4) has attracted dramatically growing attention for solar energy conversion due to its excellent physicochemical properties as a photocatalyst. However, its practical application is still impeded by several limitations and shortcomings, such as high recombination rate of charge carriers, low visible-light absorption, etc. As an effective solution, the electronic structure tuning of g-C3N4 has been widely adopted. In this context, firstly, the paper critically focuses on the different strategies of electronic structure tuning of g-C3N4 like vacancy modification, doping, crystallinity modulation and synthesis of a new molecular structure. And the recent progress is reviewed. Finally, the challenges and future trends are summarized.

Ensuring data quality, the main transformer load risk assessment model based on load rate characteristics is established. Further, using deep learning algorithm, the main transformer heavy and overload risk prediction model is constructed to realize the risk grade assessment and risk prediction on load feature defects. Finally, through the construction of the system platform, the basic functions such as multi-dimensional index calculation, statistics and visual display of real-time load characteristics of the main transformer are realized.

The operation procedure of the mechanical elastic energy storage unit is complex, and multiple devices need to cooperate with each other. These devices need to operate in turn according to the specified procedures to complete the operation process of unit energy storage and power generation. At the same time, before the unit operation, it is necessary to make a logical judgment on whether to execute the control command according to the state of each device, and display the normal or fault of each device in the state display area. The PLC has the advantages of flexible use, strong universality, high reliability and strong anti-interference ability. It is suitable for designing mechanical elastic energy storage logic protection system. This paper designs the logic protection system of mechanical elastic energy storage unit based on the PLC. The system has the advantages of convenient use, simple operation and good stability. The correct logic action can control the unit to execute accurately, which plays an important role in ensuring the safe operation of the unit.

Obtaining accurate channel state information (CSI) is an important prerequisite for achieving good performance of the Massive MIMO system. The traditional pilot-based channel estimation algorithm has low spectrum utilization. The channel estimation algorithm based on compressed sensing can make full use of the sparsity of the channel and realize channel estimation with fewer pilots. In this paper, wavelet denoising is combined with a sparse channel estimation algorithm based on Orthogonal Matching Pursuit (OMP), and Cramer-Rao Lower Bound (CRLB) is derived. The simulation results show that this method has better performance.

The Buckling-Restrained Braces is an excellent seismic energy dissipator. In this paper, the effects of the three core width-thickness ratios, gaps, and constraint ratios of the Buckling-Restrained Braces on the seismic performance of the Buckling-Restrained Braces are studied and modeled and analyzed by ABAQUS The simulation results show that the Buckling-Restrained Braces has the best seismic performance when the width-to-thickness ratio is 10-16; when the gap is 1-2mm, the Buckling-Restrained Braces has the best seismic performance; when the constraint ratio is about 5, the Buckling-Restrained Braces The best seismic performance.

Solar water splitting is a promising strategy for the sustainable production of renewable hydrogen and solving the world’s crisis of energy and environment. The third-generation direct bandgap semiconductor of zinc oxide (ZnO) with properties of environmental friendliness and high efficiency for various photocatalytic reactions, is a suitable material for photoanodes because of its appropriate band structure, fine surface structure, and high electron mobility. However, practical applications of ZnO are usually limited by its high recombination rate of photogenerated electron–hole pairs, lack of surface reaction force, inadequate visible light response, and intrinsic photocorrosion. Given the lack of review on ZnO’s application in photoelectrochemical (PEC) water splitting, this paper reviews ZnO’s research progress in PEC water splitting. It commences with the basic principle of PEC water splitting and the structure and properties of ZnO. Then, we explicitly describe the related strategies to solve the above problems of ZnO as a photoanode, including morphology control, doping modification, construction of heterostructure, and the piezo-photoelectric enhancement of ZnO. This review aims to comprehensively describe recent findings and developments of ZnO in PEC water splitting and to provide a useful reference for the further application and development of ZnO nanomaterials in highly efficient PEC water splitting.

With the development of information technology, microservices have been applied to more and more industries. Firstly, we introduce microservices and microservices architecture, analyse the main problem of civil affairs informatization, and explain the composition of microservices architecture. Secondly, we give the key technology of microservices which include abstract methods of microservices, microservices process management and the schedule of microservices workflow. Finally, we talk about the situation of civil affairs applications for using microservices architecture and give the conclusion.

Co has been proposed as one of the most promising candidates to replace W or Cu in interconnects, where Co-Ti could be used as a single barrier/liner to prevent Co out-diffusion into dielectric and Si substrate as well as to enhance the adhesion property. In this paper, the material and electrical properties of Co/Co-Ti/n+-Si contacts with different compositions and thicknesses of Co-Ti, with and without Ge pre-amorphization implantation (Ge PAI) were investigated elaborately. Sheet resistance (Rsh), phase formation, interfacial morphology and element distribution were comprehensively characterized in terms of four-point probe, X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) in combination with corresponding energy dispersive X-ray spectroscopy (EDX) respectively. Meanwhile, the specific contact resistivity (ρc) was extracted using refined transmission line model (RTLM) structures, and it is found that Ge PAI is indeed beneficial in reducing ρc values in Co/Co-Ti/n+-Si contacts. With the assistant of Ge PAI, the lowest ρc value of 8.56×10-9 Ω-cm2 is accomplished for Co/Co0.65Ti0.35/n+-Si contacts, which is ~47.8% reduction in contrast to that without Ge PAI.

Conceptual semantic similarity calculation is an important content in research fields such as natural language processing, machine translation and is widely used in information retrieval, knowledge acquisition, text classification, and clustering. It’s very important to development of natural language processing by improving the accuracy of semantic similarity calculation. This paper proposes a method for calculating the similarity of concepts based on the part-whole relationship between concepts. This method is based on the partial overall relationship diagram and uses the hierarchical features and positions of the concepts in the diagram to calculate the conceptual similarity.

This paper proposes a HBase connection dynamic keeping method based on the Reactor mode. This method uses the Reactor mode to implement the client connection maintenance mechanism based on the NSQ message queue. By only creating the TCP control block of the client connection and buffering it to the NSQ queue, it improves the response of the user connection and the concurrent processing capacity. By monitoring the active state of the connected TCP block in the message queue, the real-time processing capability of the connection is guaranteed. The reuse of HBase connection objects is realized through the listen-back callback mechanism, and the CPU and memory resource utilization is improved by dynamically adjusting the size of the connection object pool.

Poisson distribution is not only a very important distribution in probability theory, but also a useful tool to study the random events. Firstly, this paper gives a simple introduction of Poisson distribution and some characteristics of the Poisson distribution. Secondly, some properties of Poisson distribution are introduced and proved. In the end, some application of Poisson distribution are introduced, such as the application in the rare event and in daily life. We also do some analysis about the application of Poisson distribution.

The string beam structure is a new type of space structure, which satisfies the requirements of buildings for large spans, has good application value and broad application prospects. In this paper, the influence of the three-parameter ratio of the span, the prestress value and the number of strut on the stability of the beam string is studied. The modeling of the string member is carried out by SAP2000 software. The simulation results show that the arch structure of the stringed beam has the best stability when the span ratio is 0.25. When appropriate prestressing is applied to the structural cable, the stability of the structure will be significantly improved. The number of struts is not as good as possible. Considering the influence of the struts on the structure, choose the right amount.

Optoelectronic devices on silicon substrates are essential not only to the optoelectronic integrated circuit but also to low-cost lasers, large-area detectors, and so forth. Although heterogeneous integration of III–V semiconductors on Si has been well-developed, the thermal dissipation issue and the complicated fabrication process still hinders the development of these devices. The monolithic growth of III–V materials on Si has also been demonstrated by applying complicated buffer layers or interlayers. On the other hand, the growth of lattice-matched B-doped group-III–V materials is an attractive area of research. However, due to the difficulty in growth, the development is still relatively slow. Herein, we present a comprehensive review of the recent achievements in this field. We summarize and discuss the conditions and mechanisms involved in growing B-doped group-III–V materials. The unique surface morphology, crystallinity, and optical properties of the epitaxy correlating with their growth conditions are discussed, along with their respective optoelectronic applications. Finally, we detail the obstacles and challenges to exploit the potential for such practical applications fully.

In this paper sampling procedures for inspection by variables are discussed under the assumption that product quality characteristics are distributed by chi-square distribution. In the sampling procedure, due to the randomness of sampling, the judgment result may be inconsistent with the actual situation of product quality. That is, when the actual quality of the product is qualified, it is judged as unacceptable (at this time, a type of error in hypothesis testing is made, and we control it to make the probability of making a type of error less than or equal to 0.05). When the actual quality of the product is unqualified, it may be judged as acceptable (at this time, another type of error in hypothesis testing is made, and we control it to let the probability of making a type of error less than or equal to 0.1). In this paper the idea of nonlinear programming is adopted to determine the sampling procedure.

The three-dimension model of engine connecting rod based on 1.6-liter gasoline Engine was built using Solid works 2016. The stress and modal analysis of the built model were evaluated by Ansys Workbench. The results showed that the maximum tensile and compressive stress of engine connecting rod when performing of pulling and pressing force were 42.59 MPa and pressing 74.21 MPa respectively. The small end of connecting rod was an area which stress concentration. Last, a modal analysis was carried out, and the previous six order natural frequency and vibration mode were obtained. The effects of the stress and losing circle shape of the rod middle area on the working properties of the connecting rod were analyzed. After checking and calculation, this 1.6-liter gasoline engine connecting rod met the strength requirement. This study could provide theoretical evidence for the further optimization and design of engine connecting rod.

Product quality is a fundamental factor for supply chain to obtain a competitive advantage. This paper studies the decisions of supply chain under asymmetry information of quality effort cost, considering the quality competition of manufacturers. Transfer payment contract is introduced by comparing the Stackelberg model between symmetry information and asymmetry information. At the same time, this paper analyzes the impact of quality competition and false information strategy on supply chain quality decision. The research shows that the quality competition can improves products quality, and manufacturers tend to choose strategy of false information. Moreover, after the introduction of contract, the manufacturers will convey the true quality information and reduce the competition to optimize their own profits.

This paper proposed a log aggregation method in scale container platform. This method collects container log data from cluster nodes through system management tool and container governance tool, provides the indiscriminate collection service for different platforms, aggregates log data in time based on Storm stream processing to implement real-time performance, implement high performance and high availability of container log data aggregation under scale clusters based on Kafka as the aggregation queue of log data.

We report a robust perpendicularly magnetized β-W/CoFeB/MgO multilayer structure. For the first time, we demonstrate efficient spin–orbit torque (SOT) switching and a highly thermally stable annealing process with this structure using X-ray diffraction tests, the harmonic technique, and SOT-driven magnetization switching measurements. These results may enable applications of SOT-based magnetic random access memory, which is required for integration in the CMOS back-end-of-line process.

Echo state network (ESN), a novel recurrent neural network, has a randomly and sparsely connected reservoir. Since the output weights are computed by Moore-Penrose inverse, the ill-posed problem may exist in the ESN. To overcome this problem, ridge regression echo state network (RESN) is proposed, in which the ridge regression algorithm is used to calculate the output weights instead of linear regression. Simulation results show that the RESN has better performance than some other existing methods, thus can deal with the ill-posed problem.

We experimentally investigate the interfacial defect in the GeOlsubgxl/subg/Allsubg2l/subgOlsubg3l/subg gate stack based on ozone oxidation using X-ray photoelectron spectroscope (XPS) and electrical charateristics by capacitance-voltage (ligC-Vl/ig) measurement. For GeOlsubgxl/subg interlayer by ozone oxidation, oxygen vacancies exist and show positive charges at the Ge/GeOlsubgxl/subg interface. The Olsubg2l/subg annealing is helpful to decrease the oxygen vacancy defect. For the GeOlsubgxl/subg/Allsubg2l/subgOlsubg3l/subg interface, oxygen dangling bonds exist, and show negative charges. This work can be effectively applied to engineer the interface promotion and enhance the performance of Ge-based devices.

We report a possible dipole anisotropy on acceleration scale $g_{\dag}$ with 147 rotationally supported galaxies in local Universe. It is found that a monopole and dipole correction for the radial acceleration relation can better describe the SPARC data set. The monopole term is negligible but the dipole magnitude is significant. It is also found that the dipole correction is mostly induced by the anisotropy on the acceleration scale. The magnitude of $\hat{g}_{\dag}$-dipole reaches up to $0.25\pm0.04$, and its direction is aligned to $(l,b) = (171.30^{\circ}\pm7.18^{\circ}, -15.41^{\circ}\pm4.87^{\circ})$, which is very close to the maximum anisotropy direction from the hemisphere comparison method. Furthermore, robust check shows that the dipole anisotropy couldn't be reproduced by isotropic mock data set. However, it is still premature to claim that the Universe is anisotropic due to the small data samples and uncertainty in the current observations., Comment: 16 pages, 6 figures, 1 table

Height and weight prediction has been a popular problem in ergonomics study. In this paper, we reduce the dimension by principal component analysis and choose the best regression equation using various statistical criterion such as Residual Mean Square (RMSq), Mallow Cp and Akaike information criterion (AIC). Finally, compared with the real value, we analyze the fitting accuracy of the regression equation we proposed.

An ultraviolet (UV) sensor based on nanostructured zinc oxide (ZnO)/Si surface acoustic wave (SAW) devices was studied in this paper. The ZnO films sputtered onto Si (100) substrate showed a preferred (0002) orientation and good photoluminescence emission. For an SAW device with a wavelength of 64 μm, a frequency downshift of ~1.4 kHz was observed for the Rayleigh mode under a UV light intensity of 0.6 mW cm−2, whereas the frequency downshift for the Rayleigh mode was increased to 8.3 kHz after integrating ZnO nanorods (NRs) in the ZnO/Si SAW devices. For the SAW device with a wavelength of 20 μm irradiated under a UV light intensity of 0.6 mW cm−2, a frequency downshift of 25 kHz for the Sezawa mode was obtained compared to a shift of 12 kHz for the Rayleigh mode. After depositing ZnO NRs, the resonant frequency for the Rayleigh mode was increased to 27.4 kHz under the same UV intensity illumination, due to the significant increase in surface-to-volume ratio.