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In blast furnace smelting, the silicon content in molten iron is an important indicator of the temperature trend of the blast furnace. Due to the multi scale, non-linear, large time delay and strong coupling characteristics of the blast furnace smelting process, the control effect of silicon content in hot metal is often not ideal. Therefore, finding an effective and accurate method for controlling silicon content in hot metal is very important for blast furnace smelting. Based on this, this paper proposes a prediction and control model for silicon content in hot metal of blast furnace based on GRA–LSTM–BAS. Based on this, this paper proposes a prediction and control model for silicon content in hot metal of blast furnace based on GRA–LSTM–BAS. Firstly, the original data set is processed using wavelet analysis and normalisation processing methods. Secondly, the gray relational analysis (GRA) method is used to analyse the correlation between the input variables of the model to determine the input parameters of the model. Subsequently, a long short-term memory (LSTM) prediction model was established to obtain silicon content values at future times through feedback correction. The model was trained and tested by on-site collected data and compared with the support vector machine (SVM) model. The results show that the LSTM model can quickly and accurately predict the silicon content in hot metal, and has a good guiding significance for actual blast furnace production. Finally, the control model for silicon content in molten iron is optimised iteratively by combining the beetle antennae search algorithm (BAS algorithm). Feedback and update of the results in the model are done in real time according to errors, forming a closed-loop controller to maintain the silicon content in molten iron at an appropriate level and achieve optimal control of the silicon content.

Recent studies have suggested that the dysregulation of microRNAs (miRNAs) plays a critical role in the progression of human cancers, including gastric cancer (GC). miR-143 had been reported to function as a tumor suppressor in GC. However, the exact molecular mechanism of how miR-143 participates in GC progression remains to be determined. In this present study, we revealed that the expression of miR-143 was significantly downregulated in human GC tissues and cell lines compared with normal tissues and a normal gastric epithelium cell line. In addition, upregulation of the expression of miR-143 in a GC cell line inhibited cell proliferation and induced cell cycle arrested in the G0/G1phase. Furthermore, GATA6 was identified as a direct target of miR-143 in GC using the luciferase reporter assay. Upregulation of miR-143 inhibited the expression of GATA6 in GC cell lines. Moreover, the overexpression of GATA6 could attenuate the effect of miR-143 on cell proliferation in the GC cell lines. Collectively, these data indicated that miR-143 plays a tumor suppressor role partly through regulating the expression of GATA6 in GC. Therefore, targeting miR-143 may be a novel therapeutic method for GC.

The growth of international higher education, with an increase in inbound students and the creation of foreign university branch campuses, has made quality education available globally. But this also presents challenges for academic adjustment for international students. Although there is a significant amount of literature on the struggles faced by international students studying abroad, there is limited research on the challenges faced by students attending International Branch Campuses (IBCs) within their home countries. This study aims to fill this gap by using a qualitative exploratory approach to understand the specific challenges faced by first-year university students in China at a Sino-US international branch campus. Data was collected through interviews and focus groups with 28 students, five faculty members, and three student support staff. The findings provide valuable insights into the institutional and teaching challenges faced by these students, which are different from those faced by international students studying abroad.

In order to realize the automatic welding of pipes in a complex operation environment, an automatic welding system has been developed by use of all-position self-shielded flux cored wires due to their advantages, such as all-position weldability, good detachability, arc's stability, low incomplete fusion, no need for welding protective gas or protection against wind when the wind speed is < 8 m/s. This system consists of a welding carrier, a guide rail, an auto-control system, a welding source, a wire feeder, and so on. Welding experiments with this system were performed on the X-80 pipeline steel to determine proper welding parameters. The welding technique comprises root welding, filling welding and cover welding and their welding parameters were obtained from experimental analysis. On this basis, the mechanical properties tests were carried out on welded joints in this case. Results show that this system can help improve the continuity and stability of the whole welding process and the welded joints' inherent quality, appearance shape, and mechanical performance can all meet the welding criteria for X-80 pipeline steel; with no need for windbreak fences, the overall welding cost will be sharply reduced. Meanwhile, more positive proposals were presented herein for the further research and development of this self-shielded flux core wires.

Identified the urban soil has heavy metal pollution degree and the cause of the contamination of the overall analysis system. Through the mat lab software to realize pollution degree distribution visualization, use numerous evaluation pollution degree synthetic index methods, and then the reference neural network building the knowledge about the cause of the contamination analysis to determine the mechanism of the main causes of the pollution.

AbstractBased on the consumer questionnaires of the three traditional retailing centers, Qianmen, Wangfujing and Xidan in Beijing, this article analyzes the present features of consumer composition in the three retailing centers. What is more, the evolution course and function transition of traditional retailing centers is revealed based on the changing of consumer composition in different times. Lastly, the renewal method and development trends of traditional retailing centers are discussed based on the evaluation results in consumers’ perspective.