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.

Physical sampling of water on site is necessary for various applications like drinking water quality checking in lakes and checking for contaminants in freshwater systems. The use of water surface vehicles is a promising technology for monitoring and sampling water bodies, and they offer several advantages over traditional monitoring methods. This project involved designing and integrating a drone controller, water collection sampling contraption unit, and a surveillance camera system into a water surface vehicle (WSV). The drone controller unit is used to operate the boat from the starting location until the location of interest and then back to the starting location. The drone controller has an autopilot system where the operator can set a course and be able to travel following the path set, whereas the WSV will fight the external forces to keep itself in the right position. The water collection sampling unit is mounted onto WSV so when it travels to the location, it can start collecting and holding water samples until it returns to the start location. The field of view (FOV) surveillance camera helps the operator to observe the surrounding location during the operation. Experiments were conducted to determine the operational capabilities of the robot boat at the Ayer Keroh Lake. The water collection sampling contraption unit collected samples from 44 targeted areas of the lake. The comprehensive examination of 14 different water quality parameters were tested from the collected water samples provides insights into the factors influencing the pollution and observation of water bodies. The successful design and development of a water surface surveillance and pollution tracking vehicle marks the key achievements of this study. The developed collection and surveillance unit holds the potential for further refinement and integration onto various other platforms. They are offering valuable assistance in water body management, coastal surveillance, and pollution tracking. This system opens up new possibilities for comprehensive water body assessments, contributing to the advancement of sustainable and efficient water testing. Through careful sampling efforts, a thorough overview of the substances presents in the water collected from Ayer Keroh Lake has been compiled. This in-depth analysis provides important insights into the lake’s current condition, offering valuable information about its ecological health.

The study looks at Ghana’s mining industry’s audit culture and green mining practices about their social responsibility to the communities where their mines are located. Results: According to this study, the economic motivations of mines and green mining are inversely related. Even large mining companies incur significant costs associated with their green mining initiatives because they require a different budget each year, which has an impact on their ability to maximize wealth. Conversely, mines with strong green mining initiatives enjoy positive public perception, and vice versa. Ghanaian mines do not have pre- or during-mining strategies; instead, they only have post-social and post-environmental methods. The best method for evaluating mines’ environmental performance in the community in which they operate is, according to this study, social auditing. This is primarily influenced by the mine’s audit culture, but it is also influenced by the auditor’s compliance with audit processes, audit guidelines, and, ultimately, the audit firm’s experience. The analysis confirms that Ghana’s mine environmental performance is appallingly low since local audit firms are not used in favor of foreign auditors who lack experience or empathy for the problems encountered by these mining communities. Last but not least, corporate social responsibility (CSR) is connected to Ghana’s development of green mining, either directly or indirectly. Whether the mine adopts a technocrat, absolutist, or relativist perspective on mining will determine this. The study discovered that, in contrast to the later approach, the first two views generate work in a mechanistic manner with little to no consideration for CSR.

In this regard the key factor determining the success of the mining industry is the cost of electricity. By understanding the risks associated with crypto mining industry. The method is based on systemic literature review and bibliometric analysis exploring keyword “bitcoin mining”. This review paper studies 50 papers for the period of 2019–2023. The results propose recommendations for crypto miners. Currently, the results confirm that bitcoin mainly depends on the consumption of inexpensive electricity. Consequently, the bitcoin network predominantly uses energy in regions where it is abundant and cannot be stored or exported. Most miners rely on electricity generated from hydroelectric power plants, geysers and geothermal sources, which are not easy to transport or store. Bitcoin will continue to look for such cost-effective and underutilized energy sources, as mining in urban areas or industrial centers will remain financially unviable. If the price of bitcoin stabilizes and a sufficient number of miners enter the market, it is quite possible that in the near future we may witness a fivefold increase in their energy consumption.

This research delves into the correlation between institutional quality and tourism development in a panel of nine Mediterranean countries within the European Union spanning from 1996 to 2021. The study gauges tourism development by examining tourist arrivals, while considering GDP growth rate, inflation, higher education, environmental quality, and trade as control variables representing factors influencing tourism. Institutional quality is measured through indicators such as regulatory quality, rule of law, and control of corruption. Utilizing Fully Modified Ordinary Least Square (FMOLS) and Dynamic Ordinary Least Squares (DOLS) models, the study aims to quantify the impact of these factors on tourism development. The findings indicate a positive relationship between institutional quality and tourism, shedding light on the pivotal role of institutions in tourism management and their influence on the sector. These results have implications for shaping national development strategies.

Disease epidemics may spread quickly and easily throughout nations and continents in our current global environment, having a devastating effect on public health and the world economy. There are over 513 million people worldwide who have been infected, and more than 6.2 million have died due to SARS-CoV-2. There are treatments but no cures for most viruses. Nevertheless, the spread of viruses can be limited by introducing antiviral coatings on public area surfaces and personal protective equipment (e.g., face masks). This work aims to fabricate a polymer-based coating with acrylic resin as a binder that possesses great antiviral activity against the Feline coronavirus (FCov). The chosen polymer, polyethylene glycol (PEG), is used as an antiviral agent because it contains “green” chemistry benefits such as non-toxicity, being inexpensive, readily recyclable, safe, natural, non-flammable, biocompatible, and biodegradable. The PEG/acrylic coating systems of different weight percentages were coated on the glass substrates by the spray-coating method and cured at room temperature for 24 hours. The developed PEG/acrylic coating system that contains 20 wt% of PEG exhibits the highest anti-viral activities (99.9% against FCov) compared to the other weight percentages. From this study, it has been observed that the hydrophilicity of the coating plays an important role in its antiviral activity. The developed coating has a hydrophilic property, in which the contact angle was measured at 83.28 ± 0.5°. The FTIR reveals that there are no existing toxic components or new components contained in the coating samples.