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Modern day societies and economies are becoming increasingly vulnerable to the continued erosion of the stocks and flows of essential ecosystem services. Thus, the management of complex socio-economic systems to effectively provide these essential services has become a global priority policy and academic research area. Understanding how underlying processes and functions contribute towards the provision of final ecosystem services can facilitate improved dissemination of credible, legitimate and salient information to decision-makers. This paper presents an ecosystem service value chain analysis framework that applies basic system dynamics modelling in the form of causal loop diagrams to facilitate an alternative analysis of ecosystem service value chains. A scoping application of the framework is applied to a case study for flood attenuation services in the Baviaanskloof catchment in South Africa. The framework enables the identification of forward linkages and ripple effects in individual value chains of final ecosystem services as well as the identification and assessment of challenges and opportunities within individual causal pathways. Ultimately, providing the potential to advance strategies for improving the efficiency and effectiveness of final ecosystem service provision. [ABSTRACT FROM AUTHOR]

The aim of stock assessment is to provide managers with an understanding of the biomass and age-/size-composition of a stock, stock status (ideally relative to target and reference points), and to support management decision making, often through projections and application of harvest control rules. Stock assessments are increasingly being used to form the basis for the operating models used to evaluate the ability of management strategies to achieve the goals of fisheries management. Stock assessments for rock lobsters were among the first to adopt size-structured population models as the basis for stock assessment, and population model-based stock assessments have been used extensively to evaluate management strategies for rock lobster stocks in the USA, Australia, New Zealand and South Africa. This paper identifies how closely population model-based stock assessments for rock lobsters satisfy the guidelines identified for best practices for conducting stock assessments during meetings of, for example, the Center for the Advancement of Population Assessment Methodology and papers identifying best practice guidelines for stock assessment. The paper highlights some key directions for stock assessment science for rock lobsters, including considerations related to environmental variation and climate change. [ABSTRACT FROM AUTHOR]

• A techno-economic assessment (TEA) tool was developed for AD technology. • Tool is demonstrated specifically in the context of smallholders in South Africa. • Probabilistic simulation of feasibility indicators using a Monte Carlo method. • Risk assessment was conducted using sensitivity analysis and Monte Carlo method. • Stochastic TEA can be used to assessing other AD technologies. Anaerobic digestion (AD) technology holds numerous potential benefits for farmers, however, challenges persist in terms of implementation costs and sustainability in developing countries. This paper presents a probabilistic techno-economic assessment tool for AD. A clear distinction is made between direct financial feasibility and wider (socio) economic feasibility. The tool identifies the technical- and economic factors influencing the returns of a particular AD process as well as the sensitivity of model predictions to variations in the value of the identified factors using a Monte Carlo approach. The tool is applied to assess the feasibility of a smallholder farm-based AD installation under a variety of substrates and operating conditions as an illustrative case study, where on-going flows of costs and benefits were considered over a 15-year period and discounted at a rate of 8%. The results of the case study revealed that the installation of a 10 m3 smallholder farm-based anaerobic digester are likely to be financially and economically viable with a financial benefit-cost ratio of 1.30–1.38 and an economic benefit-cost ratio ranged from 5.49 to 6.01. Risk assessment results confirmed the strong economic feasibility of a smallholder farm-based AD implementation: under the most conservative cost estimates, there is a 73% probability of achieving a financial benefit-cost ratio > 1, while there is a 96.6% probability of achieving an economic benefit-cost ratio > 1. The case study demonstrated the utility of probabilistic techno-economic assessments for informed decision making, a tool which can be readily generalized to other settings. [ABSTRACT FROM AUTHOR]

• The output power is conducted using 3D-PV model. • A new fusion of improved bi-archive multi-objective optimization algorithm is proposed. • A new hybrid MCDM method is considered to choose the most desirable configuration. • An accurate hybrid numerical method is used for validation of the proposed method. • Performance of optimum designs are evaluated for both cases: Malaysia and South Africa. Photovoltaic (PV) and Wind turbine (WT) systems are the most promising options for rural energy delivery. In the literature, numerous studies have simply considered only on economic efficiency, while maximizing dependability by a constant value for the given demand load. Moreover, a single set Pareto optimal front (PF) has been attained for the multi-objective optimization problem. Furthermore, the primary challenge of various the off-grid multiple renewable energy sources is excessive energy loss, resulting over/under sizing and a highly total cost for the system. Therefore, this paper presents a unique improved bi-archive approach to develop the diversity and convergence independently in order to find four optimum sets of PF solutions. In addition, a new integration based on best worst method (BWM) and preference ranking organization for enrichment evaluations (PROMETHEE II) method along with group decision making (GDM) mechanism are addressed to sort and rank the optimal sets PF solutions with full consistency ratios of the three experts opinions and high degree of stability in ranking configurations. The theoretical results based on actual hourly meteorological data in Malaysia and South Africa indicated that the suggested improved two-archive-BWM- PROMETHEE II-GDM method is not only able to construct a uniform set of Pareto optimal solutions with fast convergence and high diversity, but can also rank and select the most desired design for the PV/WT/Battery system. The optimum configurations of the two cases studies are composed of a single WT, 105 PV modules, and 69 batteries storages at zero LLP, 60185 ($) of LLC, and 13548018 (KWh) of P dump for Malaysia case study, meanwhile it composes of 16 WTs, 80 PV modules, and 69 batteries storage at zero of LLP, 66073 ($) of LCC, and 31371 (KWh) of P dump. The proposed standalone hybrid renewable energy sources system is verified and assessed in a comparison with existing hybrid methods in terms of increasing the reliability, lowering overall cost, and reducing wasted energy. [ABSTRACT FROM AUTHOR]

This study aimed to explore the decision-making process of patients with pregnancies affected by serious congenital abnormalities. The study design was an exploratory qualitative study. The sample for this study was pregnant individuals who had a prenatal diagnosis of a serious congenital abnormality and were offered termination of pregnancy. Semi-structured face-to-face interviews with closed and open-ended questions, recorded and transcribed verbatim, were used to collect the data; this was then analyzed using a thematic data analysis approach. Five topics were developed: "Health care services", "Home", "Being a mother", "Finding meaning", and "The aftermath". The first four topics describe the decision-making process where the participants filtered through multiple factors to reach their final decision. Although the participants consulted with their families, partners, and community, they made the final decision themselves. The final topics describes activities which were necessary for closure and coping. This study has provided valuable insight into the decision-making process, which can be used to improve services offered to patients. Information should be communicated clearly with follow-up appointments to discuss further. Healthcare professional should show empathy and assure the participants that their decision is supported. • There are limited qualitative data on termination of pregnancy decision-making for serious congenital abnormalities in the African setting. • This paper provides insight into the decision-making process of pregnant individuals from the Western Cape, South Africa. • Decision-making for terminating pregnancy affected by congenital abnormality is multifaceted but with one deciding factor. • Contrary to what is anecdotally expected, in this study the participants made the final decision. • Tragic optimism was necessary for the participants to carry on with their lives. [ABSTRACT FROM AUTHOR]

Cost of unserved energy provides an economic measure of the cost of electricity interruptions to electricity customers. These values inform investment and refurbishment decisions related to the power system, with the aim of optimizing network reliability. This paper reports on the development of an economic model to estimate the value of electricity reliability in South Africa by Eskom to meet regulatory requirements. The model allows for the scalability of COUE from national level to more detailed resolutions. The impact is that decisions for power system investment can be made to meet the needs of planning and regulatory applications. [ABSTRACT FROM AUTHOR]

• GCAOA is applied for parameter extraction of the TD PV model to predict the output current of the PV model. • Non-dominated multi-objective principle is proposed for constructing sets of Pareto optimal solutions using three conflicting objectives. • A new integration based on MOO and MCDM aided by numerical methods are considered to choose the most desirable configuration. • MODA based on AHP-VICKOR-GDM method is used for validation of the proposed method. • Performance of optimum designs are evaluated using hourly meteorological data for one year. This paper presents a new optimum design for an off-grid hybrid solar photovoltaic (PV), wind turbine (WT), and battery storage system for power isolated dwellings in Malaysia and South Africa. Selecting a desirable design of the WT/PV/Battery system among a wide variety of configurations, particularly at a favorable level of reliability, lowering the total cost, and reducing the surplus energy, remains a challenging task. The procedure of this work is summarized as follows: First, the parameter of the three diode PV model is optimally extracted from datasheet information to forecast the output power of the Yingli PV module. Then, the upper and lower variables bounds of the WT/PV/Battery system are intuitively determined. Afterward, the numerical method is employed to identify every possible configurations inside the design space. The non-dominated multi-objective principle is then established to generate optimal sets of Pareto front solutions. Finally, an integration of the best worst method, technique for order of preference by similarity to ideal solution, and group decision making technique are employed to weight the objectives with complete consistency ratios and rank the optimal designs based on practical judgments. The performance results showed that the optimal designs are comprised of 1 WTs, 105 PV modules (21 in series and 5 in parallel), and 69 storage batteries with zero loss of load probability (LLP), 60185.47 ($) of life cycle cost (LCC), and 13548017.77 KWh of excess energy for Malaysian scenario. While the optimum configuration of the South African case study consists of 16 WTs, 80 PV modules (20 in series and 4 in parallel), and 69 storage batteries with a favorable LLP values of 0.00068, 59180.15 ($) of LCC, and 19174160.54 ($) of excess energy, respectively. It can be concluded that the proposed methodology for finding appropriate size of the WT/PV/Battery system is capable of operating with extremely confident dependability while minimizing the overall cost of the system and minimizing the surplus energy. [ABSTRACT FROM AUTHOR]

In this paper we analyze the role of network effects and consumer heterogeneity in the adoption of mobile phones. We estimate the decision to adopt a mobile phone using panel survey data of South African households between the years 2008 and 2012, which includes interviews with all adult household members. We construct variables which approximate network effects on the household level and find that the greater the number of mobile phones in the household, the greater the likelihood that the other household members will also adopt a mobile phone. Moreover, network effects depend on who in the household adopts a mobile phone. Without within-household network effects the penetration of mobile phones of 76.4% in 2012 would be lower by about 9.9 percentage points. The decision to adopt a mobile phone is also explained by observed and unobserved consumer heterogeneity. [ABSTRACT FROM AUTHOR]

Informal paratransit operators using a range of vehicle types (including pickup trucks, small buses, and motorcycles) are a major provider of mobility in rural areas of the developing world. The paper describes a mixed method approach used to examine such operators’ decisions about vehicle deployment, route frequency, network organisation, and pricing in three rural districts in South Africa. New evidence is presented showing that the condition of rural roads (both paved and unpaved) affects the quantity and quality of public transport services provided, as well as the fares charged to passengers. This strengthens the case for judicious infrastructure investment as a way of improving rural access and livelihoods, and suggests how this might happen by way of leveraging better private sector responses. We also describe the emergence of a differentiated service hierarchy involving a variety of vehicle types suited to different operating conditions, and based on intentional coordination among operators of minibus and pickup truck (‘bakkie’) services. We argue that governments should promote such coordination and innovation in rural transport markets. [ABSTRACT FROM AUTHOR]