Prevention and control of coal spontaneous combustion are key to coal mining and storage. Existing technologies for the detection of coal spontaneous combustion have limitations, but coal spontaneous combustion creates some serious disasters in areas of the world where coal mining and/or storage exists. New technologies to detect coal spontaneous combustion are urgently needed to reduce the loss of life and resources. The article reviews the main techniques employed to detect coal spontaneous combustion and their advantages and disadvantages; it also reviews the good application prospect of acoustic temperature measurement technology on coal spontaneous combustion and introduces the basic principle of acoustic coal temperature measurement. The evolution of combustion sound and the propagation and attenuation of acoustic waves in quasi-porous media are discussed to form the basis for the development of acoustic thermometry technologies that can be used to accurately identify acoustic signals and temperature fields in loose coal. The concept of "single-source" coal temperature measurement to "dual-source" coal temperature measurement achieved by using combustion sound and an additional sound source device in the automatic combustion of loose coal in the mined area is discussed. The deep learning methods and correlation analyses are available to map the relationships between combustion sound, coal temperature, and sound velocity, and acquire coal temperature from dual source composite acoustic signals. The study lays the foundation for the development of acoustic thermometry technologies that have applications in different stages of combustion and applied to the early warning, prevention, and control of spontaneous combustion in coal, and it contributes to improving the environmental safety and efficiency of coal mining and storage.

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Wenzhou-Kean University (WKU), a Sino-US Cooperative University in China, adopts the English Immersion Program across curricular programs. Perceived positive influences on students' learning of this instructional model remain scarce. Hence, this paper aimed to determine the correlation between the English Immersion Program, Academic Performance, and Gender among Chinese-ESL students at WKU. Convenience, random, and snowball sampling of 283 students, a response rate of 10.5%, were applied to represent the WKU student population. Descriptive-correlational design for data analysis was used in this cross-sectional research project. Conclusively, findings revealed a significant strong positive relationship between course type, immersion location, instructional design, and academic performance. Course length and academic performance showed a significant moderate positive relationship. Gender and English Language Learning significantly differ. Male students hold higher perceptions of their writing skills and knowledge mastery in learning efficiency. Other indicators do not. Interestingly, findings showed no significant difference in students' subjective assessment in their listening, reading, and writing skills in comparison to the objective assessments provided by external institutions.

Generally regarded as important ways for students to engage in class, class discussion and class participation are placed at the heart of the class. This paper aimed to determine the correlation between the class discussion and class participation in universities. Convenience and purposive sampling of 105 undergraduates have completed the survey of this correlational study. As for the study design, the cross-sectional design was chosen because this research only has one contact with study population. Descriptive and inferential statistics have be used in this study to provide in-depth data analysis. According to this study, most of the students responded “agree” to class discussion and participation, interpreted as “good”. Findings revealed that there is a significant relationship between class discussion and class participation, in which it demonstrated that students who engaged in class discussion are more likely to promote their participation in class. Finally, this paper gave related recommendations to the faculties.