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石蜡加热器是浸出车间石蜡尾气回收工艺中的重要设备，石蜡加热器温度闭环系统是典型的非线性、时变、不确定性系统，难以建立精确的数学模型。为提高石蜡加热器电动调节阀温度闭环控制效果，以检测石蜡加热器的温度偏差（e）和温度偏差变化率（ec）为输入，模糊PID控制器的KP、KI、KD为输出，构造了二输入三输出的模糊PID控制器。以西门子S7-300 PLC为下位机，WINCC组态软件为上位机，采用STEP 7软件编写模糊PID控制的算法程序，并将程序下载到S7-300 PLC存储卡中,利用S7-300 PLC对电动调节阀开度进行调节，从而实现石蜡加热器温度闭环控制。模糊PID控制器应用于浸出车间石蜡加热器温度闭环控制系统可以减少系统超调量，具有响应速度快、稳定性高等优点，提高了石蜡加热器温度闭环控制系统的运行效率。 Paraffin heater is an important equipment of paraffin vent gas recovery process in leaching workshop. The temperature closed-loop system of paraffin heater is a typical nonlinear, time-varying and uncertain system, which is difficult to establish an accurate mathematical model. In order to improve the temperature closed-loop control effect of electric regulating valve of paraffin heater, taking the temperature deviation e and temperature deviation change rate ec of paraffin heater as inputs and KP, KI and KD of fuzzy PID controller as outputs, a two input three output fuzzy PID controller was constructed. Taking Siemens S7-300 PLC as the lower computer and WINCC configuration software as the upper computer, the algorithm program of fuzzy PID control was compiled with STEP 7 software, and the program was downloaded to S7-300 PLC memory card. S7-300 PLC was used to adjust the opening of electric regulating valve, so as to realize the temperature closed-loop control of paraffin heater. The fuzzy PID controller applied to the temperature closed-loop control system of paraffin heater in leaching workshop can reduce the overshoot of the system, and has the advantages of fast response speed and high stability, thus improving the operating efficiency of the temperature closed-loop control system of paraffin heater.

The problem of corrosion in oil and gas pipelines is one of the major factors affecting the process safety and efficient sustainability development of the oil and gas industry. To gain a better understanding of global research trends and dynamics in the field of oil and gas pipeline corrosion and to advance the development of corrosion control technology, we conducted a literature review using a sample of 1,745 papers from the Web of Science (WOS) database published from 2002 to 2022. We employed a bibliometric analysis approach employed to investigate the distribution of publications over time, geographic regions, major organizations, major authors, journal cocitation, and literature cocitation, and to identify research hotspots and frontiers. The results revealed an exponential growth in the overall number of papers, with the most rapid increase occurring in the last 4 years. China, the US, Canada, the United Kingdom, and Brazil emerged as the most active countries in oil and natural gas pipeline corrosion research, and Mexico, Canada, and Australia also exhibited significant influence in the field. The journals Engineering Failure Analysis, Corrosion, and Corrosion Science had the highest number of publications and impact in this domain. Notably, Corrosion Science stood out as the most influential and highly regarded journal in the corrosion field. The fundamental theories and research framework in the realm of oil and natural gas pipeline corrosion have been primarily established, and a large number of research directions and frontier branches are emerging. The impact of flow parameters on corrosion, pipeline reliability assessment, and analysis of corrosion defects and failures are identified as the three main development paths in this field. In terms of research methodologies, machine learning techniques are becoming increasingly prevalent, with a growing number of studies adopting various machine learning methods. Among these methods, explainable deep learning is at the forefront of development in the field of oil and natural gas pipeline corrosion. [ABSTRACT FROM AUTHOR]

Many studies have shown that the brain can process subliminal numerals, i.e., participants can categorize a subliminal number into two categories: greater than 5 or less than 5. In the context of many studies on the unconscious integration of multiple subliminal stimuli, the issue of whether multiple subliminal numbers can be integrated is contentious. The same-different task is regarded as a perfect tool to explore unconscious integration. In the two experiments reported, we used a same-different task in which a pair of masked prime numbers was followed by a pair of target numbers, and participants were asked to decide whether the two target numbers were on the same (both smaller or larger than 5) or different sides (one smaller, the other larger than 5) of 5 in magnitude. The results indicated that the prime numbers could be categorized unconsciously, which was reflected by the category priming effect, and that the unconscious category relationship of the two prime numbers could affect the judgment on the category relationship of the two target numbers, as reflected by the response priming effect. The duration of the prime-to-target interstimulus interval (ISI) was also manipulated, showing a positive compatibility effect (PCE) of category priming and a negative compatibility effect (NCE) of response priming no matter whether the ISI was short (50 ms) or long (150 ms). The NCE, which occurred when the prime-to-target ISI was relatively short in this study, contradicted the conventional view but was consistent with previous results of unconscious integration based on an attention modulation mechanism. Importantly, this study provided evidence for the still-under-debate issue of numerical information integration. [ABSTRACT FROM AUTHOR]