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With the rapid development of information technology and the continuous improvement of citizens’ online participation, the rapid dissemination of public opinion through new media platforms has led to frequent incidents of online public opinion. The governance of network public opinion is difficult to achieve the desired effect only by relying on the power of the government, and the coordinated governance of network public opinion can become a realistic path to break the situation. This paper is based on the practical dilemma faced by network public opinion governance in the era of big data: big data information collection and processing are independent; The governance subjects are complex, and the rights and responsibilities between the management entities are not clear; Insufficient motivation to participate among governance subjects; Issues such as insufficient legalization of public opinion governance, and proposing to establish a government-led network public opinion data management optimization system; Improve the collaborative governance mechanism of multiple subjects of network public opinion; Implement the construction of network public opinion common interests and value system; Adhere to suggestions such as legalized collaborative governance of network public opinion to optimize the collaborative governance system of network public opinion.

Grinding balls in wet ball mill are important consumables in mine grinding equipment, which have poor wear resistance and large consumption. It is imperative to find excellent wear-resistant materials for the grinding balls. Carbidic Austempered Ductile Iron (referred to as CADI) was used as small and medium-sized wet ball mills. This grinding ball has the advantages of less wear, low crushing rate, power saving and low noise. However, the CADI grain boundaries are distributed with net-like eutectic carbides, which seriously damage the continuity of the matrix. In addition, the mechanism of corrosion wear and impact fatigue is lack of research due to complex phase composition and unclear mechanism of phase properties on improving performance. So CADI can’t be applied to the grinding balls in large wet ball mill. Based on the above problems, this paper first analyzed the heteronucleation mechanism and adsorption mechanism of M3C type carbides by using the first principle of microalloying elements, and then verified it by combining with experimental results. Then the thermodynamics and kinetics of austenite homogenization and isothermal transformation of ductile iron containing carbides were analyzed by means of modeling calculation and experiment. On this basis, a new type heat treatment process comprising super-high temperature pretreatment and austempering treatment (S&A treatment) was used to process CADI, which provides a new idea for further improving toughness of CADI. Finally, the CADI corrosion wear and impact fatigue failure mechanism were revealed by analyzing the change rule of the sample surface and cross section after corrosion wear and impact fatigue.

In order to study the characteristics of thermal environment and comfort of residential buildings during winter in hot summer and cold winter (HSCW) climate zone of China, this study conducted a questionnaire survey and field test. It was found that 70.9% of residential buildings in HSCW climate zone had space heating equipment, among that the percentage of air conditioning, electric equipment (electric oil-filled radiator and fan heater) and other were 56.0%, 27.6% and 16.4%, respectively. Furthermore, 77.3% (48.7%) of residents only heat their bedrooms (living rooms), and 76.5% of residents heat their rooms only in cold weather, which shows the “part-space” and “part-time” space heating characteristics in HSCW climate zone. For rooms with space heating, the thermal environment is category I in general, but more than 30% of these residents hope a higher indoor temperature. For rooms without space heating, the indoor temperature is below the hygiene limit of 12°C, which belongs to category II, but thermal feeling for 55% of residents is cold and 90.9% of residents hope a warmer indoor environment. The results indicated that the existing evaluation criteria in HSCW climate zone are inconsistent with the thermal sensation and expectation, and an advanced evaluation criterion is needed.

In order to improve the thermal environment of residential buildings in winter for Xinjiang, this research conducted a field test and a survey of residential buildings under typical heating methods. The results show that the indoor temperature and humidity are dynamically changing, and the variation of central heating and gas wall-mounted furnace fluctuated less than that of coal heating. Furthermore, the thermal environment evaluation shows that the thermal comfort level under gas wall-mounted furnace heating are the highest, which belongs to category Ⅰ. For the central heating and coal stove, only 12% and 26% of buildings achieve to category Ⅱ. Moreover, it is found that the acceptable temperature range of coal furnace heating residents can be as low as 19.5°C, while that of central heating and gas wall-mounted furnace heating is 20.3°C~25.7°C, which relate to the clothing insulation of residents under different heating methods. In addition, all residents almost have the same habit of window opening behaviour during heating period, and 72% of residents open windows for ventilation. Correspondingly, 62% of residents feel dry during heating season, which induce xerosis cutis, dry mouth and other uncomfortable symptom, and can be improved by using humidifier, planting plants and so on.

At present, the development of rural tourism in China is faced with the embarrassment of "small scale, flat resources" and the lack of creative planning methods, which leads to the serious problem of the simplification and homogeneity of rural tourism products. From the perspective of cultural creativity, this paper puts forward TAIM model of rural tourism product development, and takes "Guangxi district-level rural tourism poverty alleviation village" Xintian village of Quanzhou county as an example to make an empirical analysis of this model, in order to provide some inspiration for the development of rural tourism products in China.

Chemical resistance is one of the important evaluation factors of ceramic tiles. This article describes the method for determining the chemical resistance of ceramic tiles, and discusses the influence of acid-base solution concentration on the test results during the experiment, and proposes corresponding improvement measures.

Two enhanced biological phosphorus removal (EBPR) reactors were operated in synthetic wastewater with different Chemical Oxygen Demand/Phosphorus (COD/P) ratios. The sludge samples at different sample times were lyophilized and characterized by Fourier Transform Infrared (FTIR) spectroscopy. Results showed that the infrared spectral curves from two reactors were similar but the intensities were different at specific wavenumbers. The spectral intensities at 1260cm-1 and 890cm-1 of the sludge samples from the reactor at low COD/P ratios were relatively stronger, but those of the reactor at high COD/P ratios were relatively weaker. The principal component projection plot of FTIR spectra analyzed with principal components analysis (PCA) showed that the sludge samples at the same COD/P ratios assembled together implicating the principal component projection plot could discriminate the sludge samples from different reactor. The infrared peak near 890cm-1 was separated and integrated with Gaussian peak fitting method. The integrated areas were correlated to the polyphosphate content in the sludge. Results showed that the prediction values were in good accordance with those determined by chemical method. This work provides a new method for the recognition of polyphosphate in sludge and provides a basis for the rapid determination of polyphosphate.

Service innovation has become an important way for manufacturing companies to obtain and maintain their competitive advantages. Organizational implants have been proven to enhance service innovation in manufacturing companies, while the rise of big data offers new opportunities for it. This study aims to explore the impact path from organizational implants of a manufacturing company to service innovation in the context of big data with the application of Single Case Study Method, and XI’AN SHAANGU POWER is selected as research object. The findings are suggested as follows: (1) There are two ways of organizational implants to achieve service innovation for manufactures. One is employee implants, and the other is device implants. (2) Employee implants can create relationship capital, and device implants can generate data resources. (3) Relationship capital has a direct and indirect positive impact on service innovation through professional knowledge acquisition and customer demands mining. (4) Data resources have an indirect positive impact on service innovation through customer demands mining and product technology upgrading.

Micro hydropower and small hydropower are densely distributed, and coincide naturally with the core area of the ecological barrier. In view of the conflict of interests between small and micro hydropower and ecological equilibrium, and based on the existing research results of green small hydropower evaluation criteria, a relatively complete diagnostic index system of small and micro hydropower cascade development and ecological correlation is established from four aspects of environment, economy, management and sociality. The diagnostic index system of hair and ecology correlation suggests that people should not only develop and utilize water energy resources, but also give priority to the dream of protecting the natural ecological environment.

To clarify the effects of nutrient addition on algal growth during the early stages of phytoplankton bloom, an microcosm experiment was conducted in early spring; it included two groups of in situ samples: sediment plus lake water (S+W), representing the nominal “control”, and sediment plus 50% BG11 medium and 50% lake water (S+BW), representing the treatment of nutrient addition. The results demonstrated the recruitment biomass of non-cyanobacteria in the treatment group was about 46.7% of that in the control group, and the recruitment biomass of cyanobacteria in the treatment group was approximately 5 times than that in the control. After recruitment, nutrient addition generated remarkable stimulation of the growth of all algae, especially cyanobacteria. The results suggested that the stimulation by nutrient addition of algal growth after recruitment may be responsible for the occurrence of phytoplankton blooms, and the more pronounced promotion of cyanobacteria than non-cyanobacteria was explainable for the strengthening of the dominance of cyanobacteria during eutrophication.

Irrigation of agricultural land is the main water consumer in the arid and semiarid regions. The accurate time series of daily evapotranspiration (ET) at the field scale is crucial for irrigation water management. Here, we presented an integrated approach to field-scale ET mapping by combing METRIC (Mapping Evapotranspiration at High Resolution with Internalized Calibration) with trapezoidal framework of vegetation fraction and land surface temperature (fv-Trad). This approach fed with Chinese satellite HJ-1 (environmental and disaster monitoring and forecasting with a small satellite constellation) images was used to map daily ET over the desert-oasis irrigation fields in the middle of the Heihe River Basin, Northwest China. The results showed that time series of daily ET derived from HJ-1 were well consistent with the in situ measurements (coefficient of determination (R2) of 0.95, root mean square error (RMSE) of 0.31 mmd–1, mean absolute percentage error (MAPE) of 12.0% at Daman station; R2 of 0.89, RMSE of 0.16 mmd–1, and MAPE of 13.2% at Huazhaizi station). The rapid variation of ET could be precisely captured by HJ-1, especially when rainfall or irrigation events occurred between successive acquisitions of satellite data. Meanwhile, the spatiotemporal variation of monthly ET is closely related to crop growth. Daily ET at field scale will support a variety of local interests in water use and irrigation management for both planning and regulatory purposes.

Relevance of the research topic. With the rapid development of the social economy and technology, the number of existing cars and drivers has increased rapidly, and the construction of the urban road information management system has been relatively lagging behind, leading to the incompatibility of the existing traffic management model with the rapidly growing demand for transportation. Intelligent transportation systems (ITS) have been developed very complete and mature in many developed countries in the world and are widely used. With the development of technology, intelligent transportation systems will be increasingly used in urban traffic. The development of intelligent transport will be a promising direction for the development of transport in cities of the second and third echelon.

With the continuous development of the Internet financial industry, its impact on people's daily life is growing. Under the influence of the information technology and the financial innovation, the volatility of the financial market has been significantly enhanced, and the financial risk has become increasingly serious. The COVID-19 in 2020 still has a profound impact on the global financial market. The reasonable measurement of the financial risks is the most important step in the financial risk management. Based on the sample analysis of the Standard & Poor's 500 Index from January 3, 2013 to June 30, 2020, this paper measures the risks by analyzing and calculating the value at risk (VaR) of the sample data by different methods. This paper mainly establishes the ARMA model, the GARCH model based on bayese statistics, and the POT model based on the extreme value theory, and compares and analyzes the VaR values obtained by the three models. Finally, the effectiveness of VaR is tested by VaR backtracking test, and the advantages and disadvantages of the methods are compared and evaluated.

Chlorophyll-a (Chl-a) accurate inversion in inland water is important for water environmental protection. In this study, we tested the Genetic Algorithm optimized Back Propagation (GA-BP) neural network model to precisely simulated the Chl-a in an inland lake using Landsat 8 OLI images. The result show that the R2 of GA-BP neural network model has increased 28.17% compared to traditional BP neural network model. Then this GA-BP model was applied to another two scenes of Landsat 8 OLI image with the R2 of 0.961, 0.954 respectively for March 26 2018, October 26 2018. And the spatial distribution have shown a reasonable result of Chl-a variation in Lake Donghu. This study can provide a new method for Chla concentration inversion in urban lakes and support water environment protection on a large scale.

Deep sea mining, as a frontier area in China, urgently needs to make progress in automatic navigation technology. In order to improve the operation efficiency of the seabed mining machine on the soft seabed, the submarine mining vehicle which complete the mining work in a certain mining area need to enter the next mining area quickly and economically. As a classical algorithm, the majority of scholars consider that A * algorithm is the most practical path planning search algorithm. Considering the limitation of operation conditions, the three-dimensional diagram is transformed into two-dimensional diagram by interpolation method when the seabed terrain conditions allow, and then the obstacles can be marked in two-dimensional diagram. A* algorithm was applied into the path planning of mining truck. The simulation results of the paper show that path cost, turning time and turning mode should be considered in the process of avoiding obstacles.

Accurate simulations of cyclic viscoplastic deformation behaviors of single crystal superalloys which are widely used for the manufacture of gas turbine blades are important for the effective design and safety assessment in practice. In this context, based on the in-phase thermomechanical fatigue (IP TMF) and out-of-phase thermomechanical fatigue (OP TMF) experiments of the nickel-based single crystal superalloy with [001] orientation, a modified constitutive model has been developed to describe the deformation behavior under thermomechanical loadings. The TMF experiment results indicate that stable hysteresis loops with remarkable ratcheting appear in both IP TMF and OP TMF. And it’s worth noticing that the ratcheting growth direction of IP TMF and OP TMF are opposite. By introducing a Schmid stress rate related term to the back stress evolution equation, the slip-based Walker’s constitutive model is modified in this study. And the simulation results of the deformation behavior reveal good agreement with the experiments under different IP TMF and OP TMF conditions.

A nano-composite coating was developed by adding nano-SiO2 to a home-made Waterborne fluorine-containing epoxy resin. The surface hydrophlicity of the coating was investigated by the contact angle with water. As the particle sizes of SiO2 changed from 7-18nm, the water contact angle of the films changed from 62.8° to 85.6°. The surface energy of the coating was calculated out through measuring the contact angles of the coating with water and 1-bromonaphthalene. The presence of SiO2 significantly enhanced the corrosion resistance of the composite coatings, which showed two times than that of the neat waterborne fluorine-containing epoxy coatings. And the thermos dynamic stability of the composite coatings has been significantly improved. When the silica content is 2.0%, the coating has the largest contact angle. Other performance of the coating was investigated in terms of their thickness, flexibility, pencil hardness, impact resistance.