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In this paper, the biomass graphene fibre industrialisation project is taken as the research object. Moreover, the development characteristics of the project in the field of industrial application and the financial status of the current company are taken into comprehensive consideration. The financial data from 2014 to 2018 are selected for quantitative analysis. First of all, this paper specifically divides the risk into four dimensions, depending upon the project’s financial status, which involves financing risk, investment risk, business risk, and other risks These are analyzed and studied from the internal and external causes of enterprise risk. Secondly, by comparing various research methods, the author chooses the TOPSIS entropy weight method suitable for H Company to analyse its data in the past 5 years and identifies the main risk points faced by enterprises in the industry according to entropy weight. The results show that the risk index for each year is: 2017 > 2021 > 2019 > 2020 > 2018. In early 2017, the average financial status of all companies in the development of the whole project industry was at the bottom point, but in 2015, there was a huge improvement in the financial situation, and in 2019, it stabilised after the decline of the average safety index. At the same time, the average total assets of each company in the biomass graphene fibre industrialisation project showed an increasing trend from 2017 to 2021, with the most significant increase in 2019 (514.135 million yuan), an increase of 119.14% compared to 2018. Thirdly, the average value of debt also reached the highest in 2019, with the value of debt reaching 383.248 million yuan, an increase of 427.54% compared to 2018. The risk assessment system proposed in this paper provides good guidance for the risk assessment of biomass graphene fibre industrialisation projects.

As a large power consumer, the iron and steel industry urgently needs to improve productivity, reduce energy consumption, and save costs by revolutionizing energy management. In this study, we design a power demand management system for the iron and steel industry, and around the load management module, we propose a data-driven strategy based on daily load situational awareness and introduce the random forest model into daily load forecasting in the iron and steel industry. At the same time, the projection principle is applied to improve the traditional gray correlation similar day selection algorithm, and a combination method of daily load forecasting based on the gray projection improved random forest algorithm is proposed. The electric load data of the iron and steel industry in a specific region is utilized as an experimental sample to investigate the model’s forecasting performance and the impact of the data-driven strategy. The model for daily load forecasting in this paper has an average relative error of 1.18%, which is better than other models. The application of the data-driven strategy brought about 6.99% and 6.69% reductions in load demand and basic electricity cost. The data-driven strategy for the steel industry based on the Random Forest model can predict electric loads more accurately and reduce energy costs, as shown by the results.

The rate of return on education can measure the size of the return on investment in education, which is an important research area related to national development. The purpose of this paper is to analyze and discuss the relationship between education, regional economic development, and related influence variables using a multilayer linear model. CGSS data of 31 provinces and cities in 2021 are chosen as the empirical analysis data, which are divided into east, middle, and west regions according to geographic location, and the differences in industrial development of the three major regions are measured in terms of upgrading of industrial structure, seniorization, rationalization, urbanization, investment in education, and technological development. Create a model to evaluate the impact of industrial structure upgrading on education investment return in each region. Separately, the slope prediction model includes education variables and regional economic development variables to examine the predictive impact of regional economic growth on the return on education investment. The coefficient of the cross-level interaction term between years of education and regional economic development has a value of 0.07829, and it passes the 1% statistical significance test with a significant cross-level interaction effect. It indicates that the higher the degree of regional economic development, the greater the role of educational human capital in promoting residents’ income, i.e., the rise in the degree of regional economic development will significantly increase the return on investment in education.

Abstract China's technology is developing rapidly, and the number of patent applications has surged. Therefore, there is an urgent need for technical managers and researchers that how to apply computer technology to conduct in-depth mining and analysis of lots of Chinese patent documents to efficiently use patent information, perform technological innovation and avoid R&D risks. Automatic term extraction is the basis of patent mining and analysis, but many existing approaches focus on extracting domain terms in English, which are difficult to extend to Chinese due to the distinctions between Chinese and English languages. At the same time, some common Chinese technical terminology extraction methods focus on the high-frequency characteristics, while technical domain correlation characteristic and the unithood feature of terminology are given less attention. Aiming at these problems, this paper proposes a Chinese technical terminology method based on DC-value and information entropy to achieve automatic extraction of technical terminology in Chinese patents. The empirical results show that the presented algorithm can effectively extract the technical terminology in Chinese patent literatures and has a better performance than the C-value method, the log-likelihood ratio method and the mutual information method, which has theoretical significance and practical application value.

Background: Total Hip Arthroplasty(THA) is a surgical treatment for hip disease. A large amount of evidence has been reported on comparing outcomes of neuraxial(spinal or epidural) anesthesia and general anesthesia. However, it is unclear whether nerve blocks(NB) as main anesthesia technique compared with general anesthesia(GA) for THA could reduce perioperative complications. We conducted a retrospective evaluation of NB and GA, using a propensity score-matched analysis(PSMA). Methods: A total of 902 patients older than 60 years old with hip disease undergoing primary THA received combined lumbosacral plexus and T 12 paravertebral nerve blocks (n = 143) or GA (n = 759) at our institution from 2012 to 2018.Binary logistic regression was used for comparison of the primary outcomes(the incidence of delirium) and the secondary outcomes(the percentage of postoperative hemoglobin(>10g/dl), transfusion(>2 units), major cardiac events(MACE), postoperative pulmonary complications (PPC) and 30-day mortality) in the matched cohorts.Statistical analysis was performed using SPSS v 23.0. Results: Both cohorts were balanced in all included parameters after PSMA. The incidence of delirium was lower (OR 0.233,95% CI 0.064-0.845, p = 0.030) in NB group in matched cohorts. In the unmatched and matched cohorts, the percentage of Hb(>10g/dl) was higher in GA group but the incidence of transfusion(>2 units) was higher in NB group. No difference was found in the incidence of 30-day mortality in the unmatched and matched cohorts. In the unmatched cohorts, the incidence of PPC was higher and LOS was longer in NB cohort, but no difference was observed in the matched cohorts. Conclusion: In patients older than 60 years old receiving primary THA, NB could be associated with a lower incidence of delirium.

With the continuous development of China’s cross-regional interconnected power grid, large- capacity and long-distance transmission have become an important feature of China’s power grid. As the transmission capacity of single-return transmission lines continues to increase, the risk of frequency fluctuations increases, making grid operation scheduling more concerned with the performance of the unit’s primary frequency modulation. This paper tests the frequency stability of a power system under different scenarios, in which the proportion of water and thermal power in the system is different. The results represent that a system with a large proportion of hydropower has poorer frequency stability. This paper offers a method of primary frequency modulation, which proposed to improve the frequency stability of the system by increasing the time delay of the hydropower unit’s governor. The results of simulation prove that this method is an available solution to solve the problem of poor system frequency stability when a system has a high ratio of hydropower.

The utilization of geothermal energy can reduce CO2 emissions into the atmosphere. The reinjection of cooled return water from a geothermal field by a closed loop system is an important strategy for maintaining the reservoir pressure and prolonging the depletion of the geothermal reservoir by avoiding problems, e.g., water level drawdown, ground subsidence, and thermal pollution. However, the drawdown of water injectivity affected by physical and chemical clogging may occur in sandstone aquifers, and the reservoir temperature may be strongly affected by the reinjection of large amounts of cooled geothermal water, thus resulting in early thermal breakthrough at production wells and a decrease in production efficiency. In addition to the injection of cooled geothermal water, the injection of CO2 can be used to maintain the reservoir pressure and increase the injectivity of the reservoir by enhancing water–rock interactions. However, the thermal breakthrough and cooling effect of the geothermal reservoir may become complex when both CO2 and cooled geothermal water are injected into aquifers. In this paper, a simplified small-scale multilayered geological model is established based on a low-medium geothermal reservoir in Binhai district, Tianjin. The ECO2N module of the TOUGH2MP simulator is used to numerically simulate temperature and pressure responses in the geothermal reservoir while considering different treatment strategies (e.g., injection rates, temperatures, well locations, etc.). The simulation results show that a high injection pressure of CO2 greatly shortens the CO2 and thermal breakthrough at the production well. A much lower CO2 injection pressure is helpful for prolonging hot water production by maintaining the reservoir pressure and eliminating the cooling effect surrounding the production wells. Both pilot-scale and commercial-scale cooled water reinjection rates are considered. When the water production rate is low (2 kg/s), the temperature decrease at the production well is negligible at a distance of 500 m between two wells. However, when both the production and reinjection rates of cooled return water are increased to 100 m3/h, the temperature decrease in the production well exceeds 10 °C after 50 years of operation.

With the increasing installed capacity of the wind power, the power system has an obviously low inertia characteristic. It is of great significance to actively promote the virtual inertia frequency regulation technology of wind turbines (WTS) for improving the system frequency quality. The frequency regulation capability and frequency regulation effects of wind & thermal power units were analysed, and a variable inertia coordination frequency regulation strategy for different wind power penetration conditions was proposed in this paper. At the wind farm level, the dynamic frequency regulation participation coefficient of wind farms was fuzzily determined according to the operation conditions of WTS and the wind power penetration ratio. At the wind turbine level, the calculation method of the equivalent inertia constant of WTS was given based on the effective rotational kinetic energy. And the allowable range of frequency regulation parameters of WTS was determined by considering the incremental model of the system. Results indicated that the proposed coordinated frequency regulation strategy not only provided a reliable inertia support, but also maintained the stability of WTS. The frequency response performance of the high-penetration wind power system was improved.