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The purpose of this paper is to characterise the TWIN-RRT* algorithm which solves a motion planning problem in which an agent has multiple possible targets where none of them is compulsory and retrieves feasible, “low cost”, asymptotically optimal and probabilistically complete paths. The TWIN-RRT* algorithm solves path planning problems for both holonomic and non-holonomic robots with or without kinematic constraints in a 2D environment.

It was designed to work equally well with higher degree of freedom agents in different applications. It provides a practical implementation of feasible and fast planning, namely where a closed loop is required. Initial and final configurations are allowed to be exactly the same.

The TWIN-RRT* algorithm computes an efficient path for a single agent towards multiple targets where none of them is mandatory. It inherits the low computational cost, probabilistic completeness and asymptotical optimality from RRT*.

It uses efficiency as cost function, which can be adjusted to the requirements of any given application. TWIN-RRT also shows compliance with kinematic constraints.

The practical application where this work has been used consists of an autonomous mobile robot that picks up golf balls in a driving range. The multiple targets are the golf balls and the optimum path is a requirement to reduce the time and energy to refill as quickly as possible the balls dispensing machine.

The new random sampling algorithm – TWIN-RRT* – is able to generate feasible efficient paths towards multiple targets retrieving closed-loop paths starting and finishing at the same configuration.

The purpose of this paper is to present the methodology and the results on the design and development of an autonomous, golf ball picking robot, for driving ranges.

The strategy followed to develop a commercial product is presented, based on prior identification requirements, which consist of picking up golf balls on a driving range in a safe and efficient way.

A fully working prototype robot has been developed. It uses two driving wheels and a third cast wheel, and pushes a standard gang which collects the balls from the ground. A hybrid information system was implemented in order to provide a statistically relevant prediction of golf balls location, to optimize the path the robot has to follow in order to reduce time and cost. Autonomous navigation was developed and tested on a simulation environment.

Preliminary results showed that the new path planning algorithm Twin‐RRT* is able to form closed loop trajectories and improve the result over time. Kinematic constraints were already taken into account on the algorithm. This sampling based algorithm has potential usage in solving other TPP (Travelling Purchaser Problem) related problems.

The prototype feasibility is being tested in real driving ranges. It has autonomy of up to 8 h per day. It is capable of collecting up to 1,200 balls in one single journey. It weighs 130 kg and is capable of climbing slopes of up to 22°. The maximum speed is 8 km/h and the robot takes 140 min to completely sweep a 25,000 m² field at 7.2 km/h (2 m/s) average speed.

There are about 30,000 golf practice fields, of which 18,000 are located in the USA and Canada. In some countries the golf industry represents more than 15 per cent of tourism GNP. In a typical practice field, about 10,000 balls have to be picked up every day.

An important contribution of this paper is the algorithm for path planning in order to optimize the ball pick up task, reducing time and cost. There are two patents are pending concerning the technological novelties of this work.

This paper aims to define the current and potential extent of seawater intrusion in Manukan Island under different scenarios of varying recharge and pumping rates. The calibrated model was also used to predict the extent of seawater intrusion in low lying area of Manukan Island for two years with all conditions assumed to remain the same as those in December 2009.

Different scenarios of varying recharge and pumping rates based on threats received by Manukan Island were investigated. El‐Nino events and overpumping are represented by varying recharge and pumping rates. Simulation was done using SEAWAT‐2000, the latest modeling software available in groundwater modeling that couples flow and transport together.

The seawater‐freshwater mixing ratio moves landwards after two years of simulation in Scenario 1. In order to control overpumping in this study area, Scenario 2 has resulted in backward movement of the 1.4 percent seawater‐freshwater mixing ratio toward the coast after two years of prediction. The current contamination of the coastal aquifers by seawater intrusion will be more severe with an impact of El‐Nino events on groundwater resources depletion in Scenario 3. Reductions of pumping and recharge rates in Scenario 4 have worsened the seawater intrusion problem. With the aid of artificial recharge in Scenario 5, highest hydraulic heads and lowest chloride concentration were observed.

The sustainable groundwater management selected for Manukan Island's current situation will be Scenario 2. In view of the effects of El‐Nino events in the future, Scenario 5 can be implemented to restore groundwater resources. The numerical model has showed the groundwater condition during El‐Nino events and overpumping illustrated that simulation modeling is an excellent tool to understand the behavior and management of an aquifer system. The output of simulation modeling via numerical model provides a framework toward groundwater management. Thus, current study output with similar approach which will restore groundwater (artificial recharge and reduction of pumping rate) can be applied in other small islands of similar hydrogeological condition and stresses for the purpose of groundwater resource protection.

Briefly, these findings will effectively contribute to water policy analysis, planning and management in the study area to combat current as well as future seawater intrusion problem.

The West African Republic of Guinea-Bissau has been unstable since gaining its independence in 1974. The 2014 presidential and parliamentary elections are being closely analyzed to study how the United Nations and the Guinean people have reacted to the outcomes of these elections. The paper aims to discuss these issues.

Sociological methodologies and a comparative approach have been used in this paper to understand why the elections in 2014 were so important in this country.

The author finds that stability is possible in Guinea-Bissau after years of political uncertainties.

Particular focus has been paid to studying the responses of specific aspects of society, including the youth population, the political elite, the main political party, the African Party for the Independence of Guinea and Cape Verde, the opposition parties and the army and whether these different groups will be able to cooperate after electing a sustainable and relatively wide-ranging government.

In a move characterized by ambiguity, Facebook changed its name to Meta in October 2021, announcing a new era of social interaction, enabled by the metaverse technology that appears poised to become the future center of gravity for online social interactions. At first glance, the communicated change signals a radically new business model (BM) based on an unprecedented configuration of the three following components: value creation, value proposition and value capture. The purpose of this paper is to analyze Facebook’s announced changes in its BM to clarify whether the change is as radical as communicated or rather represents an incremental transformation of the current BM.

This investigation adopted an in-depth case study research method. The process included using a structured approach to collect 153 data points, including academic studies and publicly available information, followed by qualitative content analysis.

The results of our analysis of Facebook’s entrepreneurial journey indicate that the communicated strategic refocusing does not correspond to a radical BM innovation pattern. Even though Facebook’s BM might evolve into the innovation phase, as the current changes appear very futuristic, the authors estimate that the core elements of the BM will change incrementally. The investigation indicates that the underlying logic of the straightforward communicative efforts primarily serves two purposes: to improve the external perception of the company and to disseminate an internal change signal within the organization.

This paper is the first study that takes an entrepreneurship and BM perspective in analyzing Facebook’s approach in rebranding to Meta and refocusing its strategy on building the metaverse. The academic and practical relevance, as well as the potential future impact on business and society, makes the investigation of this case an intriguing prospect. Additionally, the study illuminates the difference between the communicated vision and the real impact on the business, suggesting critical questions about future large-scale rebranding efforts and their effects.

This research paper aims to empirically explore how stock market investors’ perceptions are affected by extreme climatic events like El Nino and floods in Malaysia.

This study uses structural equation modelling (SEM) to analyse the empirical data gathered through a questionnaire survey involving 273 individual investors from Bursa Malaysia between January and June 2019.

Results reveal that companies’ efforts, especially for agriculture and plantation-based industries, to adapt to climate change risk at the production, business and stock market levels significantly impact investors’ behaviour and investment decisions. Moreover, stock market investors’ climate change knowledge shows a significant moderating effect on corporate climate change adaptation initiatives and investors’ decisions to invest in Malaysian agricultural and plantation industry stocks.

This research has significant implications for practice and policy, as it measures the stock market investors’ level of awareness about climate change events and explores the companies’ strategies to reduce climatic risks to their business model.

This study shows the way to adjust the climate change information in the stock market investment decision to improve market efficiency and sustainable stock exchanges initiative.

To the best of the authors’ knowledge, this paper is the pioneer one to provide a comprehensive link between climate change events and business performances at production level, business level and stock market levels by drawing inferences from empirical data on investors’ behaviours. This study also added value in investment theories and financial literature by observing the climate change as an important factor to determine the investors’ decisions in the stock market.

This paper aims to assess whether governance processes that are taking place in the Chinchiná River basin, a coffee culture region in the Andean region of Colombia, are adaptive to climate variability and climate extremes.

A mixed research method was used by reviewing secondary research sources surrounding the institutional governance system of water governance and disaster response and semi-structured qualitative interviews were conducted with producers and members of organizations within the institutional governance system.

This study found that there is a low response to extreme events. Hopefully, the growing national awareness and activity in relation to climate change and disaster will improve response and be downscaled into these communities in the future. Although, some learning has occurred at the national government level and by agricultural producers who are adapting practices, to date no government institution has facilitated social learning taking into account conflict, power and tactics of domination.

This paper improves the understanding of the vulnerability of rural agricultural communities to shifts in climate variability. It also points out the importance of governance institutions in enhancing agricultural producer adaptive capacity.

The purpose of this paper is to examine the effects of premium subsidies provided by the Brazilian government through the Rural Insurance Premium Subvention Program (PSR) on the quantity demanded for crop insurance by grains producers of southern Brazil.

A fixed effects model was applied to an unbalanced panel data of municipalities of southern Brazil considering the years between 2006 and 2015. Three measures of crop insurance demand were considered: level of total premiums, level of total premiums per hectare and level of total liability per hectare.

Results were in line with previous literature, suggesting the existence of a positive, although inelastic, effect of the subsidy level on the demand for crop insurance. However, unitary elasticity estimates were found for all grains when considered total premiums per hectare as crop insurance demand measure.

The investigation focuses on a crop insurance program conducted in a tropical developing country – a completely different background than previously analyzed in literature. In addition, Brazilian government considers the PSR as one of its most important agricultural programs and this paper is pioneer in empirically explain the huge public investments made to the PSR through the estimation of the effects of premium subsidies on the quantity demanded for crop insurance in Brazil.

The purpose of this article is to summarize the basic literature and concepts of innovation and entrepreneurship, emphasizing the relevant studies for Latin America. The authors aim to assess the role of Latin America in the world innovative activity utilizing the production of USPTO patents.

To achieve the first objective, the authors review and summarize the relevant literature for innovation and entrepreneurship in Latin America. They also introduce each of the papers included in the current special issue of Academia. To achieve the second objective, the authors use the production of USPTO patents by Latin American residents, and examine those levels to the rest of the world.

The authors find Latin America to be a marginal contributor to the world innovative activity. Although the region represented 8.7 per cent of world GDP in 2011, it only generated 0.19 per cent of the world patents registered at the USPTO between 2008 and 2012, and only 0.17 per cent of all patents registered since 1976. However, countries such as Costa Rica and Uruguay have larger levels of patent production by 100,000 inhabitants with 7.05 and 4.72 for 1976-2012.

This introduction introduces work that continues the intense discussion on innovation and entrepreneurship in Latin America. It is to the extent of the authors' knowledge, one of the first attempts to measure the level of innovation at the regional level, and compare the performance of different countries. This special edition has implications for individuals, firms and governments striving to introduce new products, services and processes in a region that has historically confronted important barriers to innovation.

En esta introducción presentamos algunos conceptos básicos sobre innovación y empresariado, y hacemos énfasis en la literatura que ha estudiado estos fenómenos en América Latina. Evaluamos, además, el papel de América Latina en la actividad innovadora mundial, utilizando la producción de patentes registradas en la Oficina de Patentes y Marcas de Estados Unidos (USPTO), y encontramos que América Latina desempeña un papel marginal con relación a otros centros mundiales de innovación. Finalmente, se presentan los artículos de este número de la revista Academia. Esta edición especial tiene implicaciones prácticas para individuos, empresas y gobiernos, que quieran introducir nuevos productos, servicios, y procesos desde una región que históricamente ha tenido que enfrentar barreras a la innovación.

Examine the usability of rainfall and temperature outputs of a regional climate model (RCM) and meteorological drought indices to develop a macro-level risk transfer product to compensate the government of Central Java, Indonesia, for drought-related disaster payments to rice farmers.

Based on 0.5° gridded rainfall and temperature data (1960–2015) and projections of the WRF-RCM (2016–2040), the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) are calculated for Central Java over different time spans. The drought indices are correlated to annual and seasonal rice production, based on which a weather index insurance structure is developed.

The six-month SPI correlates best with the wet season rice production, which generates most output in Central Java. The SPI time series reveals that drought severity increases in future years (2016–2040) and leads to higher payouts from the weather index structure compared to the historical period (1960–2015).

The developed methodology in using SPI for historical and projected periods allows the development of weather index insurance in other regions which have a clear link between rainfall deficit and agricultural production volatility.

Meteorological drought indices are a viable alternative for weather index insurance, which is usually based on rainfall amounts. RCM outputs provide valuable insights into future climate variability and drought risk and prolong the time series, which should result in more robust weather index insurance products.