Search results

Mangrove forests are one of the most bio-diverse and productive wetland environments on earth. However, these unique tropical forest environments that occupy coastal areas are among the most threatened habitats globally. These threats include logging, conversion of land for agriculture and mariculture and degradation due to pollution over the past 50 years. The large population of resilient mangroves occupying the Turneffe Atoll area in Belize faces growing anthropogenic threats such as permanent clearing of land for housing, infrastructural development and pollution and natural factors (climate change). Given the few formal studies done to evaluate mangrove resilience at Turneffe Atoll, the purpose of this study was to evaluate mangrove resilience and nursery functions in the Turneffe Atoll Marine Reserve (TAMR).

Mangrove fish abundance and forest structure was assessed by means of a visual census and the point-centred quarter method (PCQM) for 11 sites that span across conservation and general use zones.

This study found that the more resilient mangroves (lower vulnerability ranks, higher standing biomass and higher fish biomass and abundance) exist in general use zones and warrant the need for improved mangrove conservation measures for these areas by Turneffe Atoll Sustainability Association (TASA).

Limitations of the methods for data collection included accessibility within mangrove forests stands when establishing PCQM, observer bias among data collectors, sites without surrounding mangroves were not captured to serve as a true control group and poor visibility underwater affected the estimation of fish species and size. The timeline for this research was only three months based on available funding, and no follow-up study was done to make a true comparison.

The findings of this research have a guiding role in the formulation of conservation measures such as better waste management, a robust framework for mangrove management, a communication strategy to guide public awareness and long-term monitoring surveys.

This paper aims to investigate the potential mediating effect of environmental disclosure on the relationship between corporate governance and the disclosure of social information by disaggregating Bloomberg ESG (Environmental-Social-Governance) scores. The polluting level of a company is examined for its potential moderating effect.

The focus is on the S&P 500. A structural equation model (SEM) is proposed that considers the effects of governance board constructs on the voluntary disclosure of social information (S-score) mediated by the voluntary disclosure of environmental information (E-score). The model is fit separately for two groups of companies (high-polluting and low-polluting), and the path coefficients are compared.

Consistent with prior research, board independence, gender diversity, and size positively impact voluntary environmental disclosure; board age is found to have a significant but negative effect. The estimated path coefficient from E-score to S-score is strong, positive, and significant; environmental disclosure fully mediates the relationship between corporate governance and social disclosure. This path coefficient is significantly greater for those companies in the high-polluting group.

The findings indicate that high-polluting companies may engage in increased voluntary disclosure of social information as reputation insurance. E-score fully mediates the relationship between corporate governance and S-score more strongly for high-polluting companies, suggesting this group is more likely to engage in and report on socially responsible behaviors to deflect attention away from environmental performance (i.e. greendeflecting).

This study aims to explore the influence of health-care service quality on customers’ perceived value, satisfaction, effectiveness and behavioural intention concerning district health centres (DHCs) in Hong Kong. This research also intends to assess customers’ perception of the subsidy scheme and its influence on the relationships amongst the aforementioned constructs.

The convenience and snowball sampling approaches were adopted, and the self-administered questionnaire was sent to 309 customers of DHCs.

Service quality attributes in terms of staffing and procedures positively increased customers’ perceived value and staffing, procedures and operations. Physical facilities positively promoted customers’ satisfaction, consequently improving DHCs’ effectiveness and behavioural intention. However, core treatments and services of DHCs did not impact customers’ perceived value and satisfaction. Furthermore, customers receiving subsidies exhibited a more positive perception than those without subsidies.

Health-care organisations are advised to strategically allocate resources (staffing, facilities and procedures and operations management) to optimise overall performance outcomes. DHC operators could reinforce the core services of DHCs and health-care voucher subsidies to local citizens so as to enhance the effectiveness of DHCs and behavioural intention of customers.

This study integrates the input–process–output approach in measuring the effectiveness of and customers’ behavioural intention towards newly established DHCs.

The present research attempts to delve into the climate-agriculture-migration nexus to ascertain whether the variation in agriculture output due to climatic factors has a significant influence on the emigration flows from the Asian and African continents.

The present study draws upon a rich panel of data from 27 countries (14 African and 13 Asian) between 1995 and 2020. The first stage least square, OLS and 2SLS techniques have been employed to examine the relationships between climatic factors and international migration, climatic factors and agriculture output, and agriculture output and international migration, respectively.

The results exhibit a positive relationship between temperature and international migration. The influence of temperature on agriculture output is negative but insignificant while precipitation promotes agriculture output. In addition, agriculture output negatively influences international migration, and these findings establish a climate-agriculture-migration relationship.

To counteract the climate-agriculture-migration nexus, it is incumbent upon governments to conduct extensive field trials and data collection exercises to assess the influence of climate in separate agro-ecological zones and devise policies accordingly.

The literature concerning the interrelationship between climatic factors, agriculture and migration is scarce and what is available pertains to different contexts. Moreover, no studies are based on Asia and Africa; the continents have a high dependence on agriculture and outmigration rates, and the present research covers this important gap in the literature.

This paper aims to propose a simulation-based performance evaluation model for the drone-based delivery of aid items to disaster-affected areas. The objective of the model is to perform analytical studies, evaluate the performance of drone delivery systems for humanitarian logistics and can support the decision-making on the operational design of the system – on where to locate drone take-off points and on assignment and scheduling of delivery tasks to drones.

This simulation model captures the dynamics and variabilities of the drone-based delivery system, including demand rates, location of demand points, time-dependent parameters and possible failures of drones’ operations. An optimization model integrated with the simulation system can update the optimality of drones’ schedules and delivery assignments.

An extensive set of experiments was performed to evaluate alternative strategies to demonstrate the effectiveness for the proposed optimization/simulation system. In the first set of experiments, the authors use the simulation-based evaluation tool for a case study for Central Florida. The goal of this set of experiments is to show how the proposed system can be used for decision-making and decision-support. The second set of experiments presents a series of numerical studies for a set of randomly generated instances.

The goal is to develop a simulation system that can allow one to evaluate performance of drone-based delivery systems, accounting for the uncertainties through simulations of real-life drone delivery flights. The proposed simulation model captures the variations in different system parameters, including interval of updating the system after receiving new information, demand parameters: the demand rate and their spatial distribution (i.e. their locations), service time parameters: travel times, setup and loading times, payload drop-off times and repair times and drone energy level: battery’s energy is impacted and requires battery change/recharging while flying.

Building on current debates on innovation, knowledge diffusion, and institutional dynamics, we explore the influence of national innovation systems (NISs) on international innovation collaborations in Latin America, focusing on intellectual property rights (IPR), access to scientific knowledge and regulatory quality.

We analyze data from 17 Latin American countries from 2002–2015 using time-series panel analysis to evaluate how different NIS elements affect regional cooperation for innovation.

Regulatory quality can improve international collaboration by compensating for weaker IPR and scientific knowledge bases. Interestingly, while both IPR and scientific knowledge inherently promote cooperation, stronger regulatory environments may diminish the effectiveness of IPR protections, suggesting a potential substitution effect.

The study offers actionable insights for policymakers in developing regions to help them craft more effective policies for collaboration in innovation that consider the balancing act between regulatory quality and other NIS elements.

This research shifts focus from the conventional analysis of how developing countries attract collaboration from developed nations to how they can foster innovation among themselves, providing a unique perspective on the interaction between institutional factors and innovation capabilities within the Latin American context.

This study aims to solve the problem that both the speed and the required driving power of electric vehicles (EVs) will change during the dynamic wireless charging (DWC) process, making it difficult to charge EVs with a constant power considering the overall efficiency of DWC system, the numbers of EVs and the power supply capacity. Therefore, this paper proposes the power control and efficiency optimization strategies for multiple EVs.

The wireless power charging system for multiple loads with a structure of double-sided LCC compensation topology is established. The expressions of optimal transmission efficiency and optimal equivalent impedance are derived. Taking the Tesla Model 3 as an example, a method to determine the number of EVs allowed by one transmitter coil and the overall charging power is proposed considering EV speed, power supply capacity, safe braking distance and overall efficiency. Then, the power control strategy, which can adapt to the changes of EV speed and the efficiency optimization strategy under different numbers of EVs are proposed.

In this paper, a method to determine the numbers of EVs allowed by one transmitter coil and the overall charging power is proposed considering EVs speed, power supply capacity, safe braking distance and overall efficiency. The accuracy of the charging power is good enough and the overall efficiency reaches a maximum of 91.79% when the load resistance changes from 5Ω to 20Ω.

In this paper, the power control and efficiency optimization strategy of DWC system for multiple EVs are proposed. Specifically, a method of designing the number of EVs and charging power allowed by one transmitter coil considering the factors of EV speed, power supply capacity, safe braking distance and overall efficiency is designed. The overall efficiency of the experiment reaches a maximum of 91.79% after adopting the optimization strategy.

This study aims to investigate whether mandated disclosure of engagement quality review hours provides new information that affects investors’ decision-making.

In 2014, Korean authorities mandated that audit engagement quality review hours must be disclosed in their audit reports. Using this unique field setting in Korea, this study presents empirical evidence of the policy initiative’s effect on earnings reliability by examining both pre- and post-implementation periods.

Following the initial disclosure of engagement quality review hours in 2014, the authors observe that the capital market’s valuation of quarterly earnings surprises, measured by earnings response coefficients (ERCs), was significantly lower for firms with high levels of abnormal engagement quality review hours than for other firms. This paper also finds that the observed association between engagement quality review hours and ERCs in the postregulation period hinges on the probability of earnings management, proxied by discretionary accruals and just meeting or beating analyst earnings forecast.

This paper suggests that the policy mandating disclosure of engagement quality review hours provides original information that the market considers relevant for appraising the reliability of reported earnings.

The technology adoption propensity (TAP) index is a parsimonious yet robust tool for measuring an individual’s willingness to accept new technologies. However, further investigation is still needed to evaluate its merits in non-Western countries. With this task in mind, this study assesses the psychometric properties and predictive capabilities of TAP in Turkey.

The researchers utilized an iterative process of forward-backward translation and three rounds of piloting to ensure the cross-cultural, conceptual and linguistic equivalence for the chosen tool. The final survey was conducted online on a convenience sample of 352 academics and in person for 2 other convenience samples that comprised a total of 259 municipal officers and 300 individuals.

TAP’s four-subscale structure was confirmed by a principal component analysis (PCA), and A confirmatory factor analysis (CFA) showed an acceptable fit across all samples. The total composition of the optimism, proficiency, dependence and vulnerability subscales was found to have adequate internal consistency and discriminant validity. Measurement invariance testing further demonstrated that TAP’s factorial organization was invariant across gender, age and income at configural, metric, scalar and strict levels. Finally, logistic and ordinary leas squares (OLS) regression analyses revealed that the TAP scores were predictive of prior technology adoption and use frequency.

Although these results are still preliminary, the confirmation and replication of TAP in Turkey clearly suggest that TAP is a dependable tool for assessing technology readiness that can be utilized well across different cultures.

High-performance wrought aluminum alloys, particularly AA6061, are pivotal in industries like automotive and aerospace due to their exceptional strength and good response to heat treatments. Investment casting offers precision manufacturing for these alloys, because casting AA6061 poses challenges like hot cracking and severe shrinkage during solidification. This study aims to address these issues, enabling crack-free investment casting of AA6061, thereby unlocking the full potential of investment casting for high-performance aluminum alloy components.

Nanotechnology is used to enhance the investment casting process, incorporating a small volume fraction of nanoparticles into the alloy melt. The focus is on widely used aluminum alloy 6061, utilizing rapid investment casting (RIC) for both pure AA6061 and nanotechnology-enhanced AA6061. Microstructural characterization involved X-ray diffraction, optical microscopy, scanning electron microscopy, differential scanning calorimetry and energy dispersive X-ray spectroscopy. Mechanical properties were evaluated through microhardness and tensile testing.

The study reveals the success of nanotechnology-enabled investment casting in traditionally challenging wrought aluminum alloys like AA6061. Achieving crack-free casting, enhanced grain morphology and superior mechanical properties, because the nanoparticles control grain sizes and phase growth, overcoming traditional challenges associated with low cooling rates. This breakthrough underscores nanotechnology's transformative impact on the mechanical integrity and casting quality of high-performance aluminum alloys.

This research contributes originality and value by successfully addressing the struggles in investment casting AA6061. The novel nano-treating approach overcomes solidification defects, showcasing the potential of integrating nanotechnology into rapid investment casting. By mitigating challenges in casting high-performance aluminum alloys, this study paves the way for advancements in manufacturing crack-free, high-quality aluminum alloy components, emphasizing nanotechnology's transformative role in precision casting.