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[Objective] Due to the scarcity of helium resources, insufficient production, high external dependence and single source, the security situation of helium resources in China is very severe. Utilizing salt caverns for helium storage is a significantly advantageous technology for large-scale helium storage that can effectively guarantee the helium supply capacity and improve helium security. However,China is devoid of underground salt cavern helium storage in operation, and related research and construction are still in the stage of initial development, requiring targeted feasibility and key technology researches. [Methods] Based on an investigation of helium resources and helium storage construction as well as China's experience in salt cavern gas storage construction, the feasibility of salt cavern helium storage construction in China was analyzed, and the suggestions on the development of key technologies for salt cavern helium storage were proposed,such as site evaluation, airtightness evaluation, cavern construction, storage construction, and helium injection and extraction. [Results] China is facing a high risk of helium supply disruption, necessitating the enlargement of reserve capacity. Salt cavern is suitable for large-scale helium storage for its satisfying performance in security and airtightness. The construction of salt cavern helium storage is feasible to increase China's helium reserve, giving that China has abundant salt cavern resources and a technological base for cavern construction. In addition, it is necessary to perform targeted research on key technologies for salt cavern helium storage construction, considering the geological conditions and helium resource conditions for storage construction in China differ from those in foreign countries. The salt mine in the southeast coastal area is close to the import and consumption of helium, and the transportation cost is low, so it can be used as the preferred storage site for the construction of salt cavern helium storage in China. [Conclusion] It is recommended to construct salt cavern helium storage in China in stages.At the early stage, 1 to 2 helium storage caverns should be constructed to explore and verify the construction technology of helium storage and ensure a stable supply of helium in China, after that more caverns should be constructed gradually to build up a strategic reserve that can meet China's helium demand for 5 to 10 years.

This paper proposes a regression algorithm to statistically relate the relationship between the relationship variables and proposes a multiple linear regression model to conduct a linear correlation study between a dependent variable and multiple independent variables. The factors that affect the value of merchant reputation in the content of consumer evaluation are regressed and analyzed, and a model for evaluating merchant reputation is proposed based on the regression results. In the merchant reputation evaluation model, the Bayesian algorithm and multi-source data fusion method are used to calculate the merchant weight, the Euclidean distance is used to calculate the platform weight, and the judgment matrix is constructed to calculate the merchant e-commerce reputation score. In the model performance test, 10 Taobao merchants are randomly selected for reputation calculation. The highest merchant reputation scores of 4.582 and 4.584 can be obtained for merchants S9 and S10, and the index scores are more accurate. The original Taobao reputation scores of merchants S4, S8, and S9 are all 4.97. At the same time, the model in this paper calculates them to be 4.404, 4.304, and 4.582, respectively, which are more reflective of the real reputation level of merchants.

With the continuous development of science and technology level, remote sensing technology has a wide range of application prospects in water pollution monitoring. The study combines the Grab-Cut image segmentation algorithm, atmospheric radiation correction, and water pollution identification to construct a remote sensing technology-based method for monitoring water pollution. The research is focused on analyzing the water quality distribution pattern of the upper and lower lakes in the sample lake area using the constructed water pollution monitoring method. On this basis, from the four dimensions of water pollution prevention and control, recycled water recycling, ecological restoration and protection, and environmental monitoring, the comprehensive management measures for water pollution are proposed. The pollutant contents of the upper and lower lakes before and after the management are compared to explore the effect of the comprehensive management of water pollution. The results show that COD contributes 86.77% to the water pollution in the sample lake area. The water quality of the upper and lower lakes is more distributed by class V and class III, which account for 36.67% and 43.33%, respectively. The proposed water pollution monitoring method is able to accurately identify and classify the pollution. After the comprehensive treatment, the COD and ammonia nitrogen content of the upper lake decreased by 30.51% and 37.43%, and that of the lower lake decreased by 35.90% and 39.06%. The effect of water pollution treatment was remarkable.

In the era of e-commerce economy, how to mine and study the different values of customers is an essential factor affecting the development of e-commerce enterprises. Based on this, this paper uses a clustering algorithm to mine and study the value of e-commerce customers. The research firstly constructs RFM e-commerce customer value identification framework, designs e-commerce customer value evaluation indexes and calculates the weights of the value indexes, and then uses K-means clustering algorithm and classical artificial bee colony algorithm to improve the Calculation, and completes e-commerce customer refinement based on the value of the user. The results show that the type of e-commerce customer value based on the RFMC model can be divided into eight types, based on which the e-commerce customer value is further subdivided into four types by using the clustering algorithm, namely, core customers (13.86%), supportive customers (45.38%), habitual customers (21.08%) and risky customers (19.68%). Based on the clustering algorithm, the customer value was classified into type 0 customers (low value customers), type 1 customers (high value customers), and type 2 customers (medium value customers).

In order to study the feasibility of mine DC quadrupole device in advance detection of tunneling roadway, a 3D geoelectric model of roadway advance detection is established, and ANSYS is used to simulate quadrupole device for data acquisition; the ratio method is used to eliminate the influence of interference factors such as roadway and device, and the collected data without the influence of roadway is compared with the collected data; three full space geoelectric models are established to study the response of quadrupole device to different abnormal body positions, and the response characteristics of quadrupole device to low resistance abnormal body are obtained; the practicability of this method is illustrated by an engineering example. The research results show that the ratio method can eliminate the influence of the roadway on the abnormal body, and realize the advance detection of the roadway with the quadrupole device. It is feasible to use the quadrupole device to collect data in the advance detection of the roadway.

He'nan Medical Team has stationed in Lin county(now Linzhou City) of He'nan Province for 60 years since November 1959 to carry out prevention and treatment research on high incidence of esophageal cancer. In the past 60 years, three generations of medical experts in He'nan Province have made a series of remarkable scientific research achievements in the molecular mechanism and early detection of esophageal cancer, intervention and prevention methods of precancerous lesions, and benefited thousands of patients. Based on the 34-year research of esophageal cancer prevention and treatment in our research group, this paper focuses on the understanding and thinking about the epidemic characteristics, key scientific issues and important research directions of esophageal cancer in China, so as to provide a reference for the prevention and treatment of esophageal cancer.

One of the solutions of healthcare may lie in the analysis of the longevity of scholars by probing the underlying reasons and determining factors. This study sets out to investigate the reasons why scholars in mathematics, physics, and chemistry generally live a longer and healthier life, and in particular, why longer than the common value, by compiling and analyzing data from information on those scholars. The society at large can learn from the research results of this paper which indicate that reading can, to a certain extent, lead to a long and a relatively healthy life.

Objective To compare the survival condition and related risk factors of the patients with ESCC between high-incidence area (HIA) and low-incidence area (LIA) of ESCC. Methods We collected the data of 38741 ESCC patients confirmed by pathology, among which, 23273 cases (60.1%) were from HIA and 15468 cases (39.9%) were from LIA. All patients underwent radical esophagectomy. Chi-square test was used to analyze the differences between groups of the patients with different clinicopathological characteristics, and Kaplan-Meier method was used to draw and Log rank test was used to assess the survival curves of the patients. Cox proportional hazards model was used to analyze the main influencing factors of survival. Results The proportion of male patients in LIA was higher than that in HIA (P < 0.001). The proportion of patients ≥50 years old in LIA was also higher than that in HIA (P < 0.001). ESCC patients in HIA had obviously better overall survival than patients in LIA (P < 0.001). HIA/LIA, gender, age at diagnosis, tumor location, differentiation, TNM stage and family history were independent factors for the survival of ESCC patients. Conclusion ESCC patients in HIA have obviously higher overall survival than those in LIA. LIA is an independent risk factor for poor survival of ESCC patients.

Potato peel, as the outermost tissue of the fruit, playing a role of protection and fresh keeping on the pulp tissue, is crucial for the design of potato harvesting machines. In this study, two types of potato ‘Yangyu 4’ and ‘Helan 14’ were selected to conduct friction, tensile and tear tests on their peel. Longitudinal and transverse tensile tests were conducted on the peels of two potato cultivars using an electronic universal testing machine, and tear tests were carried out on peels as well. The static friction coefficient for different materials, stress-strain curves and tear force-deformation curves of the peels were obtained and the tensile strength, elastic modulus, failure strain tear strength of the peels were measured. The results showed that the maximum value of the static friction coefficient against metallic materials was $$0.616 \pm 0.118$$ and $$0.867 \pm 0.104$$ against rubber materials, respectively. The maximum values of the tensile strength, elastic modulus, fracture strain, tear strength were 1.648 MPa, 0.388 MPa, 4.5%, 0.326 kN·m-1, respectively. Scanning electron microscopy images show that many compact and regular polygonal similar-grain grid structures distributed onty the epidermis surface and microcrack basically did not exist on the peel. The spherical micro-convex structures arranged closely and linearly at the boundary of the grid structure. Hierarchical structure surface with spherical micro-convex structures was one of the reasons for its outstanding friction coefficient. The bearing capacity of the peel depended on the number and distribution of grid structures on the surface, and the size and shape of the epidermal cells.

According to the problem of noise interference in the mechanical equipment fault signal acquisition,a novel mechanical equipment fault diagnosis method of wavelet shrinkage threshold based on Bayesian estimation combined with EMD is proposed. The fault signal denoising characteristics of different scales are considered in proposed method. The new threshold is suitable for the situation of noise distribution. The noise reduction can be gotten by improving the threshold function. The signal components decomposed and denoised by EMD is extracted with cross- correlation and kurtosis criterion to highlight the high- frequency resonance components,the blindness of IMF component selection is avoided. The results of analysis applied to simulated signal and the measured signal show that the equipment fault can be detected accurately.

Private supplementary tutoring (PT) has expanded significantly and attracted widespread public interest in China in recent years. It deserves systematic empirical research and reflection, given its crucial theoretical and practical implications. Based on the data of a large-scale survey and testing project, this study examined its effects on the students' academic achievements in mathematics. The results revealed that PT in the current semester did not have any significant positive effect on the students' academic achievement in mathematics. This suggested that households' huge financial investment in PT failed to achieve the desired result. Accordingly, these findings imply that parents should carefully select private tutoring for their children, and the government should provide more comprehensive professional guidelines to regulate the private tutoring industry.