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This paper aims to compute demand, consumption and other avoidance saving by replacing existing geysers with split and integrated type air source heat pump (ASHP) water heaters, to prove the potential of both ASHP water heaters in both winter and summer by virtue of their coefficient of performance (COP) during the vapour compression refrigeration cycles and to demonstrate that despite the viability of both split and integrated ASHP system, the latter exhibits a better performance in terms of its COP and achievable savings and load factor.

This research emphasised the use of the data acquisition system housing various temperature sensors, power metres, flow metre, ambient temperature and relative humidity sensor to determine electrical energy consumption and useful thermal energy gained by the hot water in a geyser and storage tanks of residential ASHP water heaters. The load factors, average power and electrical energy consumptions for the 150 L high-pressure geyser, a 150 L split and integrated type ASHP water heaters were evaluated based on the controlled volume (150, 50 and 100 L) of daily hot water drawn off.

The results depicted that the average electrical energy consumed and load factors of the summer months for the geyser, split and integrated type ASHP water heaters were 312.3, 111.7 and 121.1 kWh and 17.9, 10.2 and 16.7 per cent, respectively. Finally, the simple payback period for both the split and integrated type ASHP water heaters were determined to be 3.9 and 5.2 years, respectively. By the application of the Eskom’s projected tariff hikes over the years, the payback periods for the split and integrated ASHP water heaters could be reduced to 3.3 and 4.1 years, respectively.

The experiments were conducted in a controlled outdoor research facility as it was going to be of great challenge in conducting both experiments simultaneously in a specific home. The category of the different types of ASHP water heaters was limited to one due to the cost implication. The experiment was also conducted at a single location, which is not a full representation of all the ambient conditions of the different regions of South Africa.

The experiments were done with a specific controlled volume of hot water drawn off from each of the three hot water heating devices. The experiments was structuring controlled to a specific volume of hot water drawn off and at specific period of the day and hence to not cater for random drawers and intermittent drawn off.

The findings help to assure homeowners that irrespective of the type of ASHP water heaters installed in their residence, they can be guarantee of year-round performance and a favourable payback period provided their hot water consumption is over 200 L per day. Also, although the split type ASHP water heater performed better than the integrated system the cost of installation and maintenance will be higher in a split type in comparison to the integrated type. Finally, by successful implementation of either of the ASHP water heaters the home owner can substantially save of his hot water bill.

The experimental design and methodology is the first of its kind to be conducted in South Africa. The results and interpretation were obtained from original data collected from the set of experiments conducted. Also, the authors are able to show that the introduction of back up element in an ASHP unit to run simultaneously with the vapour compression refrigeration cycles of the ASHP can reduce the COP of the overall system.

The purpose of this paper is fourfold: to experimentally determine the standby thermal energy losses in various hot water cylinders in both scenarios, without isotherm blanket installation and with isotherm blanket installation; to analytically evaluate the performance of either the geyser, split- or integrated-type ASHP water heaters based on the number of heating up cycles and total electrical energy consumptions over a 24-h period without isotherm blankets and with isotherm blankets installed; to demonstrate the impact of the electrical energy factors of the split- and integrated-type ASHP water heaters under both the scenarios (without and with the isotherm blankets installed); and to use statistical tests (one way ANOVA and multiple comparison procedure tests) to verify whether any significant difference in the standby thermal energy losses occurred for each of the heating devices under both the scenarios.

The methodology was divided into monitoring of the performance of the electrical energy consumptions and ambient conditions of the hot water heating technologies without isotherm blanket installation and with isotherm blanket installation.

The results reveal that the average standby thermal energy loss of the geyser without the installation of an isotherm blanket was 2.5 kWh. And this standby loss can be reduced to over 18.5 per cent by just installing a 40-mm thick isotherm blanket on the tank. The statistical tests show a significant mean difference in the group electrical energy consumed to compensate for the standby losses under both scenarios. In contrast, the average standby thermal energy losses for the split- and integrated-type ASHP water heaters were 1.33 kWh and 0.92 kWh, respectively. There was a reduction of 15.5 per cent and 3.5 per cent in the electrical energy consumed in compensating for standby losses for both the split and integrated types, respectively, but there was no significant mean difference in the standby losses under both scenarios for the two systems. Again, without any loss of generality, the electrical energy factor of both the ASHP water heaters decreased upon installation of the isotherm blanks.

The experiments were conducted only for a 150-L geyser and 150-L split- and integrated-type ASHP water heaters. The category of the different types of ASHP water heaters was limited to one because of the cost implication.

The experiments were not conducted with various hot water storage tanks installed in different positions (roof, inside or outside of a building wall, etc.) so that actual real-life observations could be obtained. The challenges of easy disassembling and deployment of systems and DAS to different positions were also a real concern.

The findings can help homeowners and ESCO in deciding whether to install isotherm blankets on storage tanks of ASHP water heaters on the basis of the impact of standby losses and its potential viability.

The experimental design and methodology are the first of its kind to be conducted in South Africa. The results and interpretation were obtained from original data collected from a set of experiments conducted. The findings also show that the installation of isotherm blanket on an electric geyser can result in a significant mean reduction in the standby losses. In contrast, an installation of the isotherm blankets on the storage tanks of ASHP water heaters can reduce the standby losses, but there exists no significant mean difference.

Economic events and key economic variables affect stock markets on a daily basis. Inflation is one such economic variable that influences share prices to some extent. This article focuses on two SADC countries, South Africa and Namibia, and measures the impact of inflation on share market prices in these countries. It can be concluded from the study that neither South African nor Namibian companies can offer investors a perfect hedge against inflation.

This analysis attempts a comparative specification of certain aspects of the country studies contained in this volume. The point of departure is the banking crises of the early 1990s (deep in Finland, Norway and Sweden, mini-crisis in Denmark and absent in Iceland) and the contrast to Iceland's financial meltdown in 2007/2008 (no crisis in the three, a new mini-crisis in Denmark). Detailed process tracing of the Icelandic crisis is provided. The case account is then used to shed light on the different roles of neoliberalism, economics expert knowledge and populist right-wing party formation in the five Nordic political economies.

South Africa still has a considerable housing shortage. Government has tried to overcome this situation by creating programs to provide affordable housing to poor people. However, such housing is either often rejected by the beneficiaries or these express considerable dissatisfaction. This paper thus examines how value is constructed by key role players by looking at the building requirements that they promote, and asks whether there are any significant differences between the perceptions of housing providers and that of end-users, based on building requirements and location indicators. The rationale for the paper stems from the detection that low cost housing projects provided by government housing departments in South Africa (specifically, within the Western Cape Province) are either abandoned or considered non-satisfactory by beneficiaries and, therefore, seemingly not valued by them. This leads to the perception that low cost housing developments are unsustainable.

The methodology used in the paper is based on value management, and urban and social studies literature, and on a multi-case study comprising of three low-cost housing developments.

Results show that there are significant differences between the perception of key role players regarding what are important building requirements and location indicators and the corresponding end-user preferences based on location of the development.

Following the qualitative research approach used in the research, the main study limitations encountered include communication, because the low cost housing beneficiaries are predominately non-English speaking and have low level of literacy. This required the use of oral interviews, interpreters and translation of a significant number of the surveys into English. The data collected are therefore limited to the accuracy of the translations made by the translator.

Results suggest that end-user preferences must be taken into consideration by the government and the design team when planning low-cost housing developments in South Africa, and that this could be achieved by involving the end-users in decision-making during the low-cost housing development process.

This paper is of value to the national and provincial government in South Africa because it outlines the reasons for the lack of happiness and satisfaction among the poor and disadvantaged members of the community in the low cost government subsidised housing, and it suggests steps that can be taken by government to mitigate the housing problems. The paper is also of value to other key stakeholders such as the design consultants, contractors and government officials involved in the housing delivery process.

This paper aims to analyze the modern approaches to the development of tourist value proposition and to discuss relevant cases of small cities in Russia.

The paper uses a case study approach based on the experience in Vladimir Region with respect to government and its support for tourism development.

Based on the analysis of the main approaches to the development of tourist value propositions of small cities, the experience of the Vladimir Region is used to discuss composite tourist products that combines different values for tourists.

Several recommendations are offered for developing and improving the tourist value propositions of small cities, including clear positioning of a destination from competitors, communicating values that are of high interest to target segments, event marketing, extension of tourist experiences and networking of small cities that can contribute to the composite tourist value proposition.

The main output of this paper is to provide understanding of approaches to developing tourist value propositions for small cities that can be used in transitional economies to contribute to the sustainable development of the territory, based on the experience of the Vladimir Region, Russia.

This study aimed to understand better what makes esports fans engage with streamers' live-streaming of esports gameplay. This study used the Theory of Planned Behavior (TPB) and additionally adopted streamer identification and esports game identification as moderating variables.

Data were collected from streamers' esports content streaming viewers over 18 years of age using an online survey in Amazon M-Turk (N = 307). Based on past esports live-streaming weekly watching hours, which range from 1 to 45 h, the participants were divided into lower (n = 152) and higher (n = 155) frequency groups. PLS-SEM and bootstrapping techniques were used to test the moderated mediation relationships among the constructs.

This study found a negative moderating effect of past watching experience on the relationship between attitudes and behavioral intention, and it positively moderated the path between perceived behavioral control and behavioral intention. Also, it was found statistically significant direct impacts of streamer identification (STI) and esports game identification (EGI) on attitude and subjective norms. While the indirect impact of STI on behavioral intention through attitude was statistically significant, there were no significant indirect impacts of EGI on attitude and behavioral intention through subjective norms.

Theoretically, this study extends the TPB model by exploring the two identifications (i.e. streamers and esports games) as antecedents of the focal TPB factors (i.e. attitudes, subjective norms and perceived behavioral control) and the moderating effect of prior experience based on high/low weekly watching frequencies. Practically, content creators of esports live-streaming and live-streaming platform managers can use the study’s findings to develop strategies to nurture their current and future viewership.

The purpose of this study was to build and develop mathematical models correlating ambient conditions and electrical energy to the coefficient of performance (COP) of an air-source heat pump (ASHP) water heater. This study also aimed to design a simulation application to compute the COP under different heating up scenarios, and to calculate the mean significant difference under the specified scenarios by using a statistical method.

A data acquisition system was designed with respect to the required sensors and data loggers on the basis of the experimental setup. The two critical scenarios (with hot water draws and without hot water draws) during the heating up cycles were analyzed. Both mathematical models and the simulation application were developed using the analyzed data.

The predictors showed a direct linear relationship to the COP under the no successive hot water draws scenario, while they exhibited a linear relationship with a negative gradient to the COP under the simultaneous draws scenario. Both scenarios showed the ambient conditions to be the primary factor, and the weight of importance of the contribution to the COP was five times more in the scenario of simultaneous hot water draws than in the other scenario. The average COP of the ASHP water heater was better during a heating cycle with simultaneous hot water draws but demonstrated no mean significant difference from the other scenario.

There was a need to include other prediction parameters such as air speed, difference in condenser temperature and difference in compressor temperature, which could help improve model accuracy. However, these were excluded because of insufficient funding for the purchase of additional temperature sensors and an air speed transducer.

The research was conducted in a normal middle-income family home, and all the results were obtained from the collected data from the data acquisition system. Moreover, the experiment was very feasible because the conduction of the study did not interfere with the activities of the house, as occupants were able to carry out their activities as usual.

This paper attempts to justify the system efficiency under different heating up scenarios. Based on the mathematical model, the performance of the system could be determined all year round and the payback period could be easily evaluated. Finally, from the study, homeowners could see the value of the efficiency of the technology, as they could easily compute its performance on the basis of the ambient conditions at their location.

This is the first research on the mathematical modeling of the COP of an ASHP water heater using ambient conditions and electrical energy as the predictors and by using surface fitting multi-linear regression. Further, the novelty is the design of the simulation application for a Simulink environment to compute the performance from real-time data.

This is indeed the age of revolution, when timeless attitudes are changing and new ways of living being born. To most it is a bewildering complex, with uneasy forbodirtgs of the outcome. Improvement and change, there must always be—although change is not necessarily progress—but with unrest in the schools, universities and industry, one naturally questions if this is the right time for such sweeping reorganization as now seems certain to take place in local government and in the structure of the national health service. These services have so far escaped the destructive influences working havoc in other spheres. Area health boards to administer all branches of the national health service, including those which the National Health Service Act, 1946 allowed local health authorities to retain, were recommended by the Porritt Committee a number of years ago, when it reviewed the working of the service.