Global energy agencies and commissions report a sharp increase in energy demand based on commercial, industrial, and residential activities. At this point, we need energy-efficient and high-performance systems to maintain a sustainable environment. More than 30% of the generated electricity has been consumed by HVAC-R units, and heat exchangers are the main components affecting the overall performance. This study combines experimental measurements, numerical investigations, and ANN-aided optimization studies to determine the optimal operating conditions of an industrial shell and tube heat exchanger system. The cold/hot stream temperature level is varied between 10 ℃ and 50 ℃ during the experiments and numerical investigations. Furthermore, the flow rates are altered in a range of 50–500 L/h to investigate the thermal and hydraulic performance under laminar and turbulent regime conditions. The experimental and numerical results indicate that U-tube bundles dominantly affect the total pumping power; therefore, the energy consumption experienced at the cold side is about ten times greater the one at the hot side. Once the required data sets are gathered via the experiments and numerical investigations, ANN-aided stochastic optimization algorithms detected the C10H50 scenario as the optimal operating case when the cold and hot stream flow rates are at 100 L/h and 500 L/h, respectively.
This study examines the spatial distribution of consumption competitiveness and carrying capacity across regions, exploring their interrelationship and implications for sustainable regional development. An evaluation index system is constructed for both consumption competitiveness and carrying capacity using a range of economic, social, and environmental indicators. We apply this framework to regional data in China and analyze the resultant spatial patterns. The findings reveal significant regional disparities: areas with strong consumption competitiveness are often concentrated in economically developed regions, while high carrying capacity is notable in less populated or resource-rich areas. Notably, a mismatch emerges in some regions—high consumer demand is not always supported by adequate carrying capacity, and vice versa. These disparities highlight potential sustainability challenges and opportunities. In the discussion, we address reasons behind the spatial mismatch and propose policy implications to better align consumer market growth with regional resource and environmental capacity. The paper concludes that integrating consumption-driven growth strategies with carrying capacity considerations is essential for balanced and sustainable regional development.
This study investigated the level of satisfaction among consumers of special tea (Monsonia burkeana) in the Capricorn District Municipality, Limpopo Province, South Africa. It sought to identify the factors that influenced this satisfaction. A total of 225 respondents were selected using snowball sampling, and primary data were collected through structured questionnaires. Descriptive statistics were used to analyse consumer profiles and satisfaction levels, while multinomial logistic regression determined the factors influencing satisfaction across four categories: “Not satisfied at all”, “Satisfied”, “Not sure”, and “Highly satisfied”. The results revealed an average respondent age of 29.95 years and an average annual tea consumption of 4.684 uses, with over 50% of both male and female respondents expressing satisfaction. Regression analysis indicated that market access, cultural influences, income level, and the person introducing the tea significantly influenced dissatisfaction relative to high satisfaction. The income level was the only significant factor distinguishing “Satisfied” from “Highly satisfied”
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