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In this work, a dynamic structured light 3D reconstruction method adapted to random phase shift step size is proposed for the problem of dynamic workpiece 3D reconstruction in industrial manufacturing scenes. The method firstly utilizes a structured light sinusoidal grating pattern to match the relative phase shift of the workpieces moving along the perpendicular direction of the stripes on the conveyor belt. Secondly, in order to solve the problem of non-uniform phase shift step length due to external vibration, electromagnetic radiation and other disturbing factors of the conveyor belt and other mechanical devices, the method proposes a dynamic structured light 3D reconstruction model based on RPSNet, which is based on the CycleGAN network model, and uses the AIR2U-net model proposed in this paper as the generator, and the multilayer convolutional neural network CNN as the discriminator to realize the grating map. discriminator to realize the conversion of raster map to depth map. Finally, for the problem that the network model needs a large amount of data for training and it is difficult to collect data in the actual industrial scene, this paper uses the Thing10k dataset, and the dataset made by Blender simulation software for model training. Finally, a higher quality 3D reconstruction of the workpiece is realized.

Based on the 2019 satellite remote sensing data, the survey was conducted on the open-pit stopes of the building sand mines in Shigatse, Tibet, and the relationship between the number of stopes and the area, population and population density of the district/county, as well as the distribution characteristics between the main built-up areas, administrative villages and traffic roads at the county level were analyzed. This study tentatively links the open pit of building sand mine with human aggregation and human activity space, analyzes the possible correlation, distribution rules and change characteristics between it and the typical elements of social economy, and provides a research basis for improving the efficiency of mining administration in western China.

China is one of the countries with serious land degradation problems in the world. Land degradation directly threatens the food security of our country and determines the sustainable development of social economy. In this paper, the potential evapotranspiration and moisture index are calculated to divide the climatic zone of China. Based on the NPP and precipitation data, the national rRUE is obtained by the edge function. With the climate "relative benchmark", the rules of threshold analysis is used to comprehensively evaluate the land degradation in China. The results show that: excellent land is concentrated in northeast China, western Xinjiang and eastern Qinghai-Tibet Plateau; mildly degraded land is widely and sporadically distributed in the eastern plain of China; moderately degraded land and severely degraded land are concentrated in western Inner Mongolia, southern Xinjiang and northern Qinghai-Xizang Plateau.

The plasma-assisted method was used to synthesize silver nanoparticles, and the growth process of silver nanoparticles (Ag-NPs) was monitored in real time by localized surface plasmon resonance (LSPR) absorption spectroscopy. The effect of additives on the synthesis of Ag-NPs was verified. It is found that the addition of isopropanol and glucose can increase the plasmon resonance absorption intensity of the reaction solution, and promote the synthesis of Ag-NPs. In the plasma-assisted method, the additives can effectively improve the synthesis efficiency of Ag-NPs, which has great inspiration for the synthesis of other metal nanoparticles.

Compared with the traditional methods, the fully random conformational search based on Monte Carlo is more random and comprehensive. In this paper, the structural characteristics and spectral vibration of glucose molecules are studied by this method, and the results are compared with the existing results, which are highly consistent in all aspects, confirming the scientificity and accuracy of this method. At last, the properties, functions and spectral vibrations of glucose are studied by combining electrostatic analysis and spectral analysis. This method provides a new way to study the related properties of other biomolecules.

The complication that climate change brings about has been an important issue in recent decades. In this paper, we attempt to find the inner connection between climate change and regional instability, and finally build a novel evaluation model about it. By innovatively utilizing Analytic Hierarchy Process and Entropy Weight Method combined, our model can produce a reliable climate change impact assessment. Empirical results on states of different stability provide strong evidence that our model possesses high feasibility and accuracy in practical use.

A simplified thermo-structural coupling finite element model of disc brake was developed. The contact pressure distribution of new pad was simulated under an emergency braking condition. The result shows that the contact pressure distribution of pad is not uniform when the new pad is in normal working condition. The inhomogeneity of the contact pressure is a critical cause of tangential partial wear. Compared the contact pressure distribution of new pad, uniform wear pad and tangential partial wear pad, the influence of wear amount and tangential partial wear on the contact pressure of pad was investigated. The results prove that the influence of wear amount on the contact pressure of pad is very small, while tangential partial wear has a great influence on the contact pressure of pad. The wear and force characteristics of pad are analyzed. The wear of its life cycle of pad is obtained, and the reliability and accuracy of the simulation are verified.

Bird migration has attracted an increasing attention. The study of habitats has played a vital role in the birds migratory. Previous researches, however, have encountered many problems, such as great limitations on research methods, low data utilization rate, statistics-focused and ineffective data processing and analysis methods. In this paper, the algorithm of habitat discovery is put forward by using computer’s data-mining technology based on the spatio-temporal characteristics of bird-watching data. First the algorithm detects and eliminates duplicate data to guarantee data standardization. Then density-based clustering algorithms are used to identify habitats where birds gathered. Finally the habitats of birds migratory are discovered.

Excellent performances of cutting and anti-blockageis required for the no-tillage planter, a new model of cutting-disc with oblique ripples has been developed. Obliquity angle of ripple has a strong impact on working performance, so kinematics analysis of discs with different ripple obliquity angle is conducted through ProE, the result shows that 30° is the optimum angle. And FEA shows that the largest stress is on the ripple which splits the soil, reasonable thermal treatment plan is drawn up based on the FEA.

Negative strap corrosion is an important reason for the failure of valve regulated lead acid battery. This paper selected the Pb-Sb alloy material and Pb-Sn alloy material, made an investigation on the negative corrosion resistance and hydrogen evolution of these two alloy materials by scanning electron microscope analysis, metallographic analysis, chemical study and linear sweep voltammetry, and discussed the influence of lead alloy hydrogen evolution on the negative strap corrosion. The results showed that the hydrogen evolution reaction rates of the alloys had an impact on the corrosion areas with the maximum thickness of the alloys and the depth of corrosion layers. Greater hydrogen evolution reaction rate can lead to shorter distance between the corrosion area with the maximum thickness and the liquid level; whereas the greater corrosion layer thickness can bring aggravated risk of negative strap corrosion failure.

The large-span continuous rigid frame bridge is a kind of common structural form in long-span bridges of our country, but one of the main diseases of these bridges is the excessive deflection in the mid-span, which seriously affects the safety of the structure. This paper makes a comprehensive analysis for the causes of the excessive deflection, and lists the commonly-used control measures in engineering. Simultaneously, new improvement measures and the comparative analysis of before-and-after improvements are put forward on this basis. However, these measures can be used to inhibit deflection in a certain extent, but cannot avoid the occurrence of deflection completely.

Electromagnetic coupling treatment (EMCT) is a new method to regulate material properties. To investigate the effect of EMCT on the plasticity of the Al-Cu-Mg alloy, a software simulation calculation was carried out, and then the alloy was treated with an electromagnetic field, and its mechanical properties were tested at room temperature. The simulation results reveal that the sample generates a plastic strain of 6.88*103 ppm, potentially enhancing its tensile properties. The experimental findings indicate that EMCT did not have a substantial impact on the strength and hardness of the aluminum alloy. However, it did result in a 16.9% increase in the sample’s plasticity and a 5.6% drop in the elastic modulus

The west section of Nanchuan River City is an important part of the water ecological environment of Xining city, known as the urban meeting room. In order to find out the possible causes of algal blooms in the summer of 2022, water quality detection, aquatic organism identification and sediment analysis were carried out in the main landscape ponds of the west section of Nanchuanhecheng. The results showed that 52 species of phytoplankton were identified, including 4 species of cyanobacteria, 29 species of diatoms, 14 species of green algae, 3 species of cryptophytes and 2 species of gymnophytes. There were 66 species of zooplankton, including 22 protozoa, 29 rotifers, 9 cladicornis and 6 copepods. There were 18 benthic animals, including 4 annelids, 3 molluscs and 11 arthropods. According to the detection results of aquatic organisms, water quality and sediment, the causes of algal blooms were analyzed and corresponding measures were proposed to provide reference for subsequent control work.

Local draft experiments were conducted to establish the overall thermal sensation prediction model under low pressure environment. Head, chest, hand, and ankle were exposed to local airflow under three pressure environments: 1 atm, 0.87 atm, and 0.74 atm, respectively. The skin temperature was measured and the subjective questionnaires were collected. The results showed that in cooler environment, the mean skin temperature decreased with the decrease of pressure, and people maybe more sensitive. When the environmental pressure decreased, the overall thermal sensation decreased correspondingly. Compared with the normal pressure condition, as the pressure decreased, the weight of local thermal sensation on overall thermal sensation changed a little. The weight of chest decreased while the weight of hands increased. When exposed to local draft, the four body parts showed similar influence on the overall thermal sensation under lower pressure conditions. Based on influence of pressure, temperature, and local draft speed, the overall thermal sensation prediction model for each body part was established respectively. The results indicated that the predicted values were highly correlated with the measured values. The models could be used to predict thermal sensation of people who are exposed to local draft in low pressure environment.

To ensure the forming quality of SLM and to improve the forming efficiency of SLM, this paper investigates the forming effect of Ti6Al4V specimens formed by SLM based on an interlayer strategy. The conditions for improving the relative density of the specimens are high laser power, small point distance, long exposure time and long hatch spacing. High laser power provides sufficient laser energy density in the formation of thicker powder layers, reduced point distance ensures wetting behavior of the melt pool, longer exposure time provides the time required to fully melt the powder and increased hatch distance facilitates dispersion of the laser energy density. Process parameters have a strong influence on the relative density of SLM formed specimens, and by adjusting the process the highest density of 99.99% can be achieved. The microstructure of the specimens consisted mainly of acicular martensite α′ and columnar β grains due to the effects of repeated thermal cycling. Due to the presence of martensite α′, the tensile and yield strengths of the specimens are increased, but the elongation of the specimens is reduced.

In recent years, with the rapid development of highways, traffic noise has become a risk source in the environment, and noise control has attracted wide attention. As an economical and effective method, highway noise barriers were the best way to reduce traffic noise and protect residents’ acoustic environment. At the same time, considering the various surroundings in selecting suitable materials (sound-reflective or sound-absorbing materials), types (such as concrete, organic glass, foam metal and photovoltaic noise barriers) and structures (such as vertical, T-shaped, Y-shaped, and inverted L-shaped) could greatly improve the sound reduction performance of barriers. This paper summarizes the current development of noise barriers from perspectives of the material, type and structure to introduce a variety of noise barriers and provides a reference for relevant research. With these analyses, it is possible to design more cost-effective and appropriate noise barriers for particular areas.

This paper addresses the event-triggered H∞ state estimation problem for a class of discrete recurrent neural networks subject to variance-constraint and fading measurements. The phenomena of fading measurements are described by introducing a set of mutually independent random variables, which reflect that each sensor has individual missing probability. In addition, for the purpose of energy saving, an event-triggered H∞ state estimation scheme is used for time-varying neural networks to determine whether the measurement output is transmitted to the estimator or not. Some sufficient conditions are obtained to guarantee that the estimation error system satisfies both estimation error variance constraint and prescribed H∞ performance requirement. Finally, the feasibility of the proposed event-triggered H∞ state estimation method is verified by a numerical example.

Taking the incomplete measurements and the weighted try-once-discard (WTOD) protocol into account, this paper develops a novel resilient set-membership state estimation (RSMSE) method for time-varying nonlinear complex networks with time-invariant delay. A classic interval matrix technique is utilized to describe incomplete measurements. The Taylor series expansion is applied to dispose the nonlinearities, where the high-order terms of the linearization errors are described by norm-bounded uncertainties. To mitigate the communication burden, the WTOD protocol is introduced, where only one node can send updated data through a shared communication network at each certain transmission step. Using the recursive linear matrix inequalities (RLMIs), a series of ellipsoidal sets including the state vector can be determined. The desirable estimator gain and a smallest possible estimation ellipsoid can be calculated via solving the convex optimization problem. Lastly, we use an illustrative example to show the feasibility of the introduced RSMSE technique.

This paper studies the pricing selection and coordination strategies for dual-channel closed-loop supply chain (CLSC) considering production diseconomies. Under the centralized and decentralized decision-making, the decision models of CLSC of retailer recycling was constructed, the effects of the manufacturer’s production diseconomy and the sales competition between manufacturer and retailer on new product pricing and waste product recycling were analysed, the optimal pricing strategy of dual-channel CLSC was given, and a “two-part tariff” coordination contract was established based on centralized decision-making. The results indicate that the profits of each member are negatively correlated with the production diseconomy and positively correlated with the degree of sales competition, the direct sales volume of manufacturer is always more than twice that of retailer, and the stronger the competition degree is, the more obvious the advantage is. Further, within the range of contract parameters that the dominant manufacturer and retailer are willing to accept, the “two-part tariff” contract can effectively realize the coordination of dual-channel CLSC.

Excessive use of chemical fertilizers in the soil will cause excessive residues of heavy metals, soil hardening and high soil alkalinity. A soil pH tester is generally used to test the soil pH scale to ensure the normal growth of crops. However, the tester cannot be used directly in the case of soil hardening and the soil should be moistened before measurement. In addition, existing soil pH testers can only perform single-point tests, and multiple tests are generally required in order to obtain accurate experimental data. Common deep soil pH test devices are difficult to use and have the problem of inaccurate measurement results due to excessive impurities in the soil in the process of use, resulting in errors in soil analysis which require secondary revision to improve the soil environment. To make up for the defects of existing technologies, this study designs a deep high-moisture soil pH tester, which has the advantage of high soil impurity filtering performance and addresses the problem of inaccurate measurement results due to excessive impurities in the soil.

Graphene oxide and carbon nanotubes supported Pt nanoparticles were successfully synthesized by wet chemical reduction method. The structures and methanol oxidation performance of the two catalysts were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy (Raman) and electrochemical workstation. The results show that graphene oxide supported Pt nanoparticles exhibits higher electrochemical active surface area, methanol oxidation activity and stability compared with carbon nanotubes. It is proposed that the well dispersed Pt on the graphene oxide plays an important role for the excellent performancefor methanol oxidation.

The quality of broadband power line carrier communication mainly depends on the carrier communication frequency. However, there is a lack of fast and effective optimal carrier frequency selection method. One frequency selection method based on frequency point optimization neural network is proposed by this paper. This method combines transmission line theory and voltage partial reflection theory to build a power line carrier channel mathematical model of the distribution network. The input frequency point sample set is used as the training set of the frequency point optimization neural network to obtain a neural network model that can predict the local optimal frequency point set. Then the actual distribution network is taken as an example for simulation analysis. When inputting any frequency range, the model outputs the corresponding optimal frequency point set. Simulation results show that the algorithm saves a lot of input impedance or channel strength testing time, while the error rate is limited to about 3%.

In order to assess whether the runway can meet safe, reliable and efficient objectives, a comprehensive evaluation indicator system needs to be established for evaluation. Firstly, the runway operation system is established, and the evaluation indicators of runway performance are divided into five aspects: personnel factors, support facility, mission demand, operating environment and management factors and then establish a comprehensive evaluation index system. Secondly, the TOPSIS evaluation model of game theory combination weighting is established, game theory is used to optimize the weights of the weights obtained by AHP and CRITIC, and the ideal solution (TOPSIS) is used to comprehensively evaluate the runway performance. Finally, the model was used to evaluate the runway performance levels of the three airports, and the three evaluation methods were compared. The results show that the results of the runway performance evaluation using the model are in line with the actual operation of the airport. The method is simple and the results are scientific and objective, and it have good versatility.

Reinforced Thermoplastic Pipe (RTP) is a composite material flexible pipe. Due to RTP superior behavior, it encouraged the industry for using to offshore and inshore applications. Marine risers and cross-country pipelines resting on elastic medium are slender flexible structures conveying fluid and exhibit complex dynamic behaviors. Therefore, it requires accurate dynamic modeling for prediction the vibration characteristics. Transfer Matrix Method for Multibody Systems (MSTMM) is one of the sophisticated methods that can be used efficiently to model large systems and calculate its vibration characteristics and dynamic responses. The size of matrices in MSTMM remains small regardless of the number of elements in the model. Having smaller matrix sizes helps to have less computational expense leading to a faster answer. Based on the MSTMM advantages and Euler-Bernoulli linear theory, transfer matrix of the pipe in both offshore and inshore industry applications is built-up for vibration analysis. Recursive eigenvalue search algorithm is used to determine the system frequencies. Numerical examples are performed to validate with those published in the open literature.

As one of the most critical stages of CG (Computer Graphics) industry, CG design & production needs the support of professional knowledge and practice experience of multidisciplinary. With the outstanding performance in knowledge sharing, integration and reuse, knowledge modeling could increase greatly the efficiency, reduce the cost and avoid repeated error in CG design & production. However, knowledge modeling of CG design & production differs greatly from those of other fields. On the one hand, it is similar to physical product design, which involves great deal of tacit knowledge such as modeling skills, reasoning knowledge and so on. On the other hand, as film, CG design & production needs a lot of unstructured description information. The heterogeneity between physical product and film makes knowledge modeling more complicated. Thus a systematic knowledge modelling method based on Ontology is proposed to aid CG design & production in this paper. CG animation knowledge is capture and organized from viewpoint of three aspects: requirements and design and production. The knowledge are categorized into static and dynamic knowledge, and Ontology is adopted to construct a hierarchic model to organize the knowledge, so as to offer a uniform communication semantic foundations for designers from different fields. Based on animation script, the CG design task model is proposed to drive the organization and management of different knowledge involved in CG design & production. Finally, we apply this method in the knowledge modeling of naked-eye animation design and production to illustrate effectiveness of this method.

This paper intends to find the critical success factors for smart green city logistics business in Fuzhou. We first investigate and collect the factors that impact the operations of smart green city logistics business. In order to acquire the experts’ assessments on the influence between each two factors, we invite the managers who serve in the top five logistics companies in Fujian and conduct expect questionnaire investigation. By using DEMATEL method, we explore the causal effect among factors. Our findings show that the government investments and green power development are the two most influential factors among all.

In 1999, China’s State Council issued a ‘Decision Concerning the Deepening of Education Reform and the All-Out Promotion of Quality Education.’ This document introduced the term ‘education industry’ ( 教育产业 ) along with two major policy changes: a dramatic expansion in university admissions and the devolution of part of the control over higher education from the central government to the provinces. Yet in 2004 top officials of the Ministry of Education publicly denied that ...

According to the environment and work styles, the underwater monitoring devices can be divided into three type, fixed monitoring device, the floating monitoring device and mobile monitoring device. Floating monitoring platform is a new type of monitoring device of the floating monitoring device, which is mainly used for underwater video monitoring of pool. as the floating platform monitoring in water motion and hydrostatic characteristics are closely related, the influent of counterweight, weight distance and floating body diameter of the structure parameters on its hydrostatic characteristics and the natural periods for roll, pitch and heave should be considered, In this work, the floating body diameter influent most, the counterweight followed, and the structure parameters have different influence on the natural periods for roll, pitch and heave , it need to be analyzed according to the concrete structure parameters.