Biomechanical analysis of little penguins' underwater locomotion from the free-ranging dive data.

Penguins are proficient swimmers, and their survival depends on their ability to catch prey. The diving behaviour of these fascinating birds should then minimize the associated energy cost. For the first time, the energy cost of penguin dives is computed from the free-ranging dive data, on the basis of an existing biomechanical model. Time-resolved acceleration and depth data collected for 300 dives of little penguins (Eudyptula minor) are specifically employed to compute the bird dive angles and swimming speeds, which are needed for the energy estimate. We find that the numerically obtained energy cost by using the free-ranging dive data is not far from the minimum cost predicted by the model. The outcome, therefore, supports the physical soundness of the chosen model; however, it also suggests that, for closer agreement, one should consider previously neglected effects, such as those due to water currents and those associated with motion unsteadiness. Additionally, from the free-ranging dive data, we calculate hydrodynamic forces and non-dimensional indicators of propulsion performance - Strouhal and Reynolds numbers. The obtained values further confirm that little penguins employ efficient propulsion mechanisms, in agreement with previous investigations.

Survey and analysis of consumers' behaviour for electronic waste management in Bangladesh.

This paper aims to establish consumer's perception of electric waste recycling and management on a national scale in Bangladesh. The attitude, willingness to pay (WTP) and consumers' behaviour were explored by conducting a questionnaire-based survey. The conclusions are based on 915 valid responses out of 2000 online survey invitations. Interestingly, 37.9% of the respondents indicated that they would accept to pay for electronic waste recycling. Analysis also shows that the preferred WTP would cover 5-10% of the recycling cost. Factors like environmental awareness, monthly income, and education level affect the consumers' WTP. Nevertheless, most of the participants believe that the Government should share the recycling cost. The study suggests that e-waste recycling can be stimulated by promoting environmental awareness, educating the public about the benefits of recycling e-waste, and making e-waste recycling more convenient. However, additional measures will likely be needed to tackle the e-waste problem. Thus, support for environmental education is imperative in order to promote environmental awareness and increase the WTP of consumers. The study outlines key characteristics of consumer-focused e-waste management archetypes and proposes an effective road map for Bangladesh.

Towards the effective E-waste management in Bangladesh: a review.

Nowadays, the electrical and electronic products are a crucial commodity for different purposes of daily life and they are multiplying five times faster than human like mobile phones, which has reached zero to 7.2 billion in only three decades. A 5-10% yearly increase in the amount of used electrical and electronic equipment that are disposed of prudently can cause environmental hazards that have an aversive effect on human health, marine life, contamination of groundwater, and reduces soil's fertility. Management of this enormous influx of electrical and electronic waste is a challenge for developing countries like Bangladesh with barebones solid waste management infrastructure. Inadequacy of public awareness, policies and poor budget in the field of waste management are few of the key factors behind this delineating scenario. In this study, the picture electrical and electronic waste productions in Bangladesh along with the recent E-waste management systems have been presented comprehensively. Based on the study, it was concluded that most of the adapted E-waste management methods are conversational and detached from current technological capability. A set of sustainable E-waste management system has been suggested along with the challenges, which might appear during the implementation of these strategies. Successful implementation of these suggested systems would advance the quality of E-waste management in Bangladesh increasing the current 35% overall E-waste recycling rate and offer enormous energy from the waste.

Towards the effective plastic waste management in Bangladesh: a review.

The plastic-derived product, nowadays, becomes an indispensable commodity for different purposes. A huge amount of used plastic causes environmental hazards that turn in danger for marine life, reduces the fertility of soil, and contamination of ground water. Management of this enormous plastic waste is challenging in particular for developing countries like Bangladesh. Lack of facilities, infrastructure development, and insufficient budget for waste management are some of the prime causes of improper plastic management in Bangladesh. In this study, the route of plastic waste production and current plastic waste management system in Bangladesh have been reviewed extensively. It emerges that no technical and improved methods are adapted in the plastic management system. A set of the sustainable plastic management system has been proposed along with the challenges that would emerge during the implementation these strategies. Successful execution of the proposed systems would enhance the quality of plastic waste management in Bangladesh and offers enormous energy from waste.