The direct expansion heat pump with solar energy is an energy conversion system used for water heating applications, air heating for air conditioning buildings, water desalination, solar drying, among others. This paper reviews the main designs and analysis of experiments in order to identify the fundamental objectives of any experiment which may be: to determine the factors that have a significant influence, to obtain a mathematical model and/or to optimize performance. To achieve this task, the basic and advanced configuration of this system is described in detail in order to characterize its thermal performance by means of energy analysis and/or exergy-based analysis. This review identifies possible lines of research in the area of design and analysis of experiments to develop this water heating technology for industrial applications.
With the popularity of smartphones, consumers’ daily lives and consumption patterns have been changed by using multi-functional apps. Convenience store operators have developed membership apps as a platform to promote their brands to consumers to create the benefits of “membership economy”. This study examined consumer behavior towards convenience store membership apps using UTAUT2. Consumers who have installed the convenience store membership apps were recruited as the target population. SPSS 23.0 was used to conduct item analysis and reliability analysis in the pretest questionnaires. The formal questionnaires were distributed online by convenience sampling method, with 375 valid questionnaires collected. Smart PLS 3.0 was conducted by analyzing the confirmatory factor analysis and structural equation model analysis. The results of the study, “performance expectancy”, “social influence”, “price value” and “habit” of convenience store member app users showed positive and significant effects on “behavioral intention”. “Facilitating conditions”, “habit” and “behavioral intention” have positive and significant effects on “actual use behavior”. “Gender” affects “habit” to have a significant moderating effect on “use behavior”. “Use experience” affects “habit” to have a significant moderating effect on “behavioral intention”. Based on the study results, the further suggestions of marketing management implications and feasible recommendations are proposed for convenience store operators to refer to in the implementation of membership app marketing management.
Latin America is increasingly contributing to scientific research on leadership, although less than other regions. What are the predominant paradigms on leadership within the scientific community in Mexico? The article reviews doctoral dissertations on leadership from the National Autonomous University of Mexico (UNAM) and the Anahuac University of Mexico (UA) defended before 2021. The findings highlight that 1) the number of doctoral dissertations has grown from 2016 onwards, especially in educational leadership. 2) In both universities a “functionalist” paradigm prevails, based on the transformational leadership model. 3) Two other leadership paradigms are present, referred to in this article as ‘political’ and ‘humanistic’. 4) These three paradigms have their characteristics and preferences in terms of research methodology, language, and reference authors. 5) The use of a paradigm is associated with the type of faculty rather than the type of university (public or private): in business faculties the functionalist paradigm predominates, in education faculties the humanist paradigm, and in political science or communication faculties the political paradigm. In conclusion, it is recommended to confirm the exploratory result obtained and to promote the dialogue between leadership paradigms.
Mind map is a new way of thinking that visualizes and visualizes radioactive thinking. The application of mind map in teaching is consistent with the expression of "development of thinking ability" in the "Chinese Curriculum Standards". Its concise construction and clear expression can, on the one hand, convey the ideas of language expressors more quickly and quickly, and on the other hand. On the one hand, it can make the language receiver easier and clearer to understand the message the other party wants to convey.This paper analyzes the application rules of mind map in classroom teaching, and expounds the application strategy of mind map in primary Chinese oral communication teaching from three aspects: picture-text combination, picture-introduction, and picture-introduction. The effective development of primary school students' innovative thinking and logical ability promotes the effective improvement of primary school students' oral communication skills.
The role of agriculture in greenhouse gas emissions and carbon neutrality is a complex and important area of study. It involves both carbon sequestration, like photosynthesis, and carbon emission, such as land cultivation and livestock breeding. In Shandong Province, a major agricultural region in China, understanding these dynamics is not only crucial for local and national carbon neutrality goals, but also for global efforts. In this study, we utilized panel data spanning over two decades from 2000 to 2022 and closely examined agricultural carbon dynamics in 16 cities of the Shandong Province. The method from the Intergovernmental Panel on Climate Change (IPCC) was used for calculating agricultural carbon sinks, carbon emissions, and carbon surplus. The results showed that (1) carbon sink from crops in the Shandong Province experienced growth during the study period, closely associated with the rise in crop yields; (2) a significant portion of agricultural carbon emissions was attributable to gastrointestinal fermentation in cattle, and a reduction in the number of stocked cattle led to a fall in overall carbon emissions; (3) carbon surplus underwent a significant transition in 2008, turning from negative to positive, and the lowest value of carbon surplus was noticed in 2003, with agriculture sector reaching the carbon peak; (4) the spatial pattern of carbon surplus intensity distinctly changed before and after 2005, and from 2000 to 2005, demonstrating spatial aggregation. This research elucidates that agriculture in Shandong Province achieved carbon neutrality as early as 2008. This is a pivotal progression, as it indicates a balance between carbon emissions and absorption, highlighting the sector’s ability in maintaining a healthy carbon equilibrium.
Copyright © by EnPress Publisher. All rights reserved.