Social science methodologies are increasingly used by conservation organisations to improve social‐ecological outcomes. However, ethnographic approaches seeking to understand organisations themselves ...and how organisational culture impacts biodiversity and social justice are rarely discussed. By exploring previous studies of the methodological considerations of organisational ethnography in conservation, we provide conservationists and ethnographers with an empirically grounded understanding of the opportunities, challenges and underlying ethical considerations of this approach.
We conducted a scoping review of a disparate body of literature where ethnographers were embedded in conservation organisations and discussed their methodology, identifying 26 studies for analysis. We then extracted information on key themes relevant to methodological process and uptake.
Our review found such research spanned the globe, with a broad range of methodological and ethical considerations related to how ethnographers and conservationists interact. For example, organisational ethnography was perceived as valuable by conservationists as it allowed tracking progress toward internal goals such as diversification of staff and providing moral and emotional support and valuable information for transforming organisational practices. However, conservationists also worried about ethnographers' presence in their organisations. A key methodological challenge we identify, corroborating with the literature, is how ethnographers can benefit organisations while supplying critique.
Based on the results, we provide recommendations and areas of reflection for conservation organisations and ethnographers. Mainstreaming organisational ethnography through attention to certain methodological considerations can be beneficial for the future of conservation organisations and the biodiversity and people they impact.
This comprehensive review investigates the growing adoption of electric vehicles (EVs) as a practical solution for environmental concerns associated with fossil fuel usage in mobility. The increasing ...demand for EVs underscores the critical importance of establishing efficient, fast-charging infrastructure, especially from the standpoint of the electrical power grid. The review systematically examines the planning strategies and considerations for deploying electric vehicle fast charging stations. It emphasizes their unique dual role as loads and storage units, intricately linked to diverse road and user constraints. Furthermore, the review underscores the significant opportunity surrounding these stations for the integration of distributed renewable energy sources. It thoroughly explores the challenges and opportunities intrinsic to the planning and localization process, providing insights into the complexities associated with these multifaceted stations. Renewable resources, including wind and solar energy, are investigated for their potential in powering these charging stations, with a simultaneous exploration of energy storage systems to minimize environmental impact and boost sustainability. In addition to analyzing planning approaches, the review evaluates existing simulation models and optimization tools employed in designing and operating fast charging stations. The review consolidates key findings and offers recommendations to researchers and grid authorities, addressing critical research gaps arising from the escalating demand for electric vehicle fast-charging infrastructure. This synthesis is a valuable resource for advancing understanding and implementing robust strategies in integrating EVs with the electrical power grid.
High-efficiency solar cells with low manufacturing costs have been recently accomplished utilizing different technologies. III-V-based tandem solar cells have exhibited performance enhancement with a ...recent efficiency of greater than 39% under AM1.5G and 47% under concentration. Integration of such III-V materials on a relatively cheap Silicon (Si) substrate is a potential pathway to fabricate high-efficient low-cost tandem solar cells. Besides, perovskite solar cells, as third-generation thin film photovoltaics (PV), have been meteorically developed at a reasonable cost. At present, there are still questions for cost reduction of perovskite materials and solar cell modules because of their limited commercialization. In this review, stacking Si solar cells with III-V material to form Si-based III-V tandem solar cells is presented with different integration technological routes. Also, perovskite/Si tandem solar cells have been reviewed alongside their main engineering challenges introduced through the fabrication of perovskite-based tandem solar cells. Finally, a comparison between III-V tandem solar cells, Si-based III-V tandem solar cells, and perovskite-based tandem solar cells is introduced so that the best technology for a specific application could be determined. The review provides a comprehensive study of two different technologies (III/V and Perovskite) to demonstrate the most valuable cost reduction availability for each.
Current mismatch due to solar cell failure or partial shading of solar panels may cause a reverse biasing of solar cells inside a photovoltaic (PV) module. The reverse-biased cells consume power ...instead of generating it, resulting in hot spots. To protect the solar cell against the reverse current, we introduce a novel design of a self-protected thin-film crystalline silicon (c-Si) solar cell using TCAD simulation. The proposed device achieves two distinct functions where it acts as a regular solar cell at forward bias while it performs as a backward diode upon reverse biasing. The ON-state voltage (
) of the backward equivalent diode is found to be 0.062 V, which is lower than the value for the Schottky diode usually used as a protective element in a string of solar cells. Furthermore, enhancement techniques to improve the electrical and optical characteristics of the self-protected device are investigated. The proposed solar cell is enhanced by optimizing different design parameters, such as the doping concentration and the layers' thicknesses. The enhanced cell structure shows an improvement in the short-circuit current density (
and the open-circuit voltage (
), and thus an increased power conversion efficiency (PCE) while the
is increased due to an increase of the
. Moreover, the simulation results depict that, by the introduction of an antireflection coating (ARC) layer, the external quantum efficiency (EQE) is enhanced and the PCE is boosted to 22.43%. Although the inclusion of ARC results in increasing
, it is still lower than the value of
for the Schottky diode encountered in current protection technology.
Vulnerability assessment in industrial IoT networks is critical due to the evolving nature of the domain and the increasing complexity of security threats. This study aims to address the existing ...gaps in the literature by conducting a comprehensive survey on the use of attack graphs for vulnerability assessment in IoT networks. Attack graphs serve as a valuable cybersecurity tool for modeling and analyzing potential attack scenarios on systems, networks, or applications. The survey covers the research conducted between 2016 and 2021(34 peer-reviewed journal articles and 28 conference papers), identifying and categorizing the main methodologies and technologies employed in generating and analyzing attack graphs. In this review, core modeling techniques for IoT vulnerability assessment are highlighted, such as Markov Decision Processes (MDP), Feature Pyramid Networks (FPN), K-means clustering, and logistic regression models, along with other techniques involving genetic algorithms like fast-forward (FF), contingent fast-forwards (CFF), advanced reinforcement-learning algorithms, and HARMs models. The evaluation of the performance of these attack graph models using IoT networks or devices as case studies is also emphasized. This survey provides valuable insights into the state-of-the-art in attack graph techniques for IoT network vulnerability assessment, identifying various applications, performances, research opportunities, and challenges. As a reference source, it serves to inform academicians and practitioners interested in leveraging attack graphs for IoT network vulnerability assessment and guides future research directions in this area.
With the aim of achieving high efficiency, cost-effectiveness, and reliability of solar cells, several technologies have been studied. Recently, emerging materials have appeared to replace Si-based ...cells, seeking economic fabrication of solar cells. Thin-film solar cells (TFSCs) are considered strong candidates for this mission, specifically perovskite-based solar cells, reporting competitive power convergence efficiencies reaching up to 25.7%. Substantial efforts have been invested in experimental and research work to surpass the Si-based cells performance. Simulation analysis is a major tool in achieving this target by detecting design problems and providing possible solutions. Usually, a TFSC adopts p-i-n heterojunction architecture by employing carrier transport materials along with the absorber material in order to extract the photogenerated electrons and holes by realizing a built-in electric field. Eventually, this dependency of conventional heterojunction TFSCs on carrier transport layers results in cost-ineffective cells and increases the possibility of device instability and interface problems. Thus, the design of p-n homojunction TFSCs is highly desirable as an essential direction of structural innovation to realize efficient solar cell operation. In this review, a summary of the fundamentals of TFSC materials, recent design and technology progress, and methodologies for improving the device performance using experimental research studies will be discussed. Further, simulation analysis will be provided by demonstrating the latest research work outcomes, highlighting the major achievements and the most common challenges facing thin film homojunction solar cell structures and the methods to improve them.
Environmental and social problems triggered by rapid palm oil expansion in the tropics have spurred the proliferation of sustainability certification systems such as the Roundtable on Sustainable ...Palm Oil (RSPO). While the RSPO aims to improve the impact of oil palm production on people and environments, its effect on local development, environmental quality, and, especially, potential trade-offs between these outcomes remain unclear. Here, we evaluate whether RSPO certification of large-scale industrial concessions has promoted village development and supported environmental quality in Indonesia, the top global palm oil producer. Using a panel dataset with observations from 11 000 villages in Kalimantan and Sumatra from 2003 to 2014, we apply rigorous quasi-experimental methods to quantify the RSPO's impacts on village development and environmental outcomes. In the short-run, RSPO contributed to environmental conservation, but had limited development outcomes. On average, relative to villages with non-certified concessions, RSPO certification reduced deforestation and protected primary forests in Sumatra and lowered the incidence of village-reported land pollution in Kalimantan. RSPO certification also increased the number of private educational facilities in Kalimantan, but had no statistically significant impacts on other development indicators. However, the trade-offs and complementarities between conservation and development vary by slope, a proxy for ecosystem fragility and oil palm profitability. On gentler slopes, we generally find complementarities between conservation and development outcomes. In Kalimantan, certification increased the number of private educational facilities and reduced deforestation and the incidence of land pollution on slopes < 2°. In Sumatra, certification retained more primary forests, decreased deforestation and the incidence of water pollution on slopes < 1°, along with a decrease in population density. Higher slopes in both locations were associated with environment and development trade-offs. We highlight the need to better understand the mechanisms behind the impacts of RSPO and emphasized how the outcomes of certification depend on the communities' bargaining power and the profitability of the land for oil palm production. Thus, we provide insights into understanding these mechanisms behind the impacts of RSPO, which is a prerequisite for improving the design of certification systems and their impacts on the ground.
Double-junction solar devices featuring wide-bandgap and narrow-bandgap sub-cells are capable of boosting performance and efficiency compared to single-junction photovoltaic (PV) technologies. To ...achieve the best performance of a double-junction device, careful selection and optimization of each sub-cell is crucial. This work presents the investigation of an all-thin-film two-terminal (2T) monolithic homojunction perovskite (PVK)/c-Si tandem cell using Silvaco TCAD simulation. The front sub-cell utilizes homojunction PVK that has a bandgap of 1.72 eV, whereas the rear sub-cell uses thin c-Si with a bandgap of 1.12 eV. Both cells are connected via a
p
++
/
n
++
silicon tunnel diode. Experimental calibration of the heterojunction PVK and c-Si cells yields power conversion efficiencies (PCE) of 18.106% and 17.416%, respectively. When integrated into an initial PVK/c-Si tandem, the resulting cell achieves a PCE of 29.38%. To compare the performance, the heterojunction PVK layer is replaced with an
n-p
homojunction PVK layer, revealing the impact of the absence of a surplus built-in electric field in the perovskite film as a strong limiting factor. Further, a thorough investigation of four distinct structures for the
n-p
homojunction PVK cell is conducted. The four structures include a complete cell, electron transport layer (ETL)-free, hole transport layer (HTL)-free, and carrier transport layer (CTL)-free structures. The results show that the CTL-free structure has significant potential after applying certain optimization techniques that result in reducing surface recombination, enhancing the built-in electric field, and improving light absorption. With the current-matching condition achieved, the tandem efficiency reaches 36.37%.
In order to protect the solar panel against reverse biasing, bypass Schottky diodes are usually connected in parallel with a string of cells which makes the circuit more complex and costly. This ...study presents a novel thin-film crystalline silicon device design using physics-based TCAD simulations. In our proposed solar cell, a P + reverse conducting layer is introduced to form an N ++ /P + /P structure. The novel device structure provides two different functions depending on the type of applied bias. It operates as an efficient solar cell when operating at forward biasing while it acts as a backward diode when reverse biased. Therefore, such a proposed device is self-protected against the reverse current. Also, it can reduce circuit complexity and manufacturing cost.
In this work, an optimization of the InGaP/GaAs dual-junction (DJ) solar cell performance is presented. Firstly, a design for the DJ solar cell based on the GaAs tunnel diode is provided. Secondly, ...the used device simulator is calibrated with recent experimental results of an InGaP/GaAs DJ solar cell. After that, the optimization of the DJ solar cell performance is carried out for two different materials of the top window layer, AlGaAs and AlGaInP. For AlGaAs, the optimization is carried out for the following: aluminum (Al) mole fraction, top window thickness, top base thickness, and bottom BSF doping and thickness. The electrical performance parameters of the optimized cell are extracted: JSC=18.23 mA/cm2, VOC=2.33 V, FF=86.42%, and the conversion efficiency (ηc) equals 36.71%. By using AlGaInP as a top cell window, the electrical performance parameters for the optimized cell are JSC=19.84 mA/cm2, VOC=2.32 V, FF=83.9%, and ηc=38.53%. So, AlGaInP is found to be the optimum material for the InGaP/GaAs DJ cell top window layer as it gives 4% higher conversion efficiency under 1 sun of the standard AM1.5G solar spectrum at 300 K in comparison with recent literature results. All optimization steps and simulation results are carried out using the SLVACO TCAD tool.
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