What is the major challenge for the design and fabrication of tandem solar cell?5 answersThe major challenge for the design and fabrication of tandem solar cells is the need to grow high-quality wide-bandgap perovskites and mitigate irreversible degradation caused by halide and metal interdiffusion at the interconnecting contacts. Another challenge is the interconnection scheme of the sub-cells in a module, and the implications on techno-economic factors. Additionally, the fabrication of two-terminal tandem solar cells using a perovskite layer is technically difficult due to damage in the substrate layers during the coating of the additional upper layers. Furthermore, the perovskite top-cell faces concerns regarding perovskite instability, including hysteresis, ion segregation, and trap states, which require mitigation strategies. The silicon bottom cell also faces challenges in achieving high power conversion efficiencies, requiring further understanding in light management and passivation technologies. Overall, these challenges need to be addressed to enable the large-scale industrialization of tandem solar cells.
What is a 3-tap triangular kernel?4 answersA 3-tap triangular kernel is a type of filter used in image processing. It is a spatial filtering technique that allows for the reduction of unwanted spatial frequency components in an image. This type of filter is implemented using a multitapped CCD delay line coefficients on-chip with a CCD imager.
Why is 3SLS better than OLS SUR and 2SLS in some cases?5 answers3SLS is better than OLS SUR and 2SLS in some cases because it provides more accurate parameter estimates and predictions. The study by Bhuller and Sigstad shows that 2SLS can identify positively weighted sums of agent-specific effects of each treatment under certain conditions. Additionally, the study by Yunianto and Sumertajaya compares 2SLS and 3SLS in predicting Fishermen Term of Trade (NTN) and finds that 3SLS gives better parameter estimates with less Mean Square Error (MSE) and higher R-squared value. Therefore, in cases where accurate parameter estimates and predictions are important, such as in models with multiple treatments and when predicting economic indicators like NTN, 3SLS is preferred over OLS SUR and 2SLS.
What are the challenges in improving the efficiency of tandem solar cell based on CIGS thin film?5 answersImproving the efficiency of tandem solar cells based on CIGS thin film faces several challenges. One challenge is the narrow compositional window for obtaining single-phase CIGS thin films, requiring a precise co-evaporation process. Another challenge is the thermal resistance of the flexible substrate, such as polyimide (PI) foils, which may not withstand the high temperature CIGS absorber formation process. Additionally, the coefficient of thermal expansion of PI foils is too large, leading to peeling-off problems of subsequently deposited Mo back electrode. Furthermore, stability and power conversion efficiency are crucial for tandem solar cells, and achieving a stable power conversion efficiency for a high bandgap perovskite solar cell is a key challenge. Finally, optimizing the optical properties of the tandem cell, such as reducing parasitic absorption in introduced layers, is necessary for improving its performance.
What are some potential applications for three-pole electrochemical systems?5 answersThree-pole electrochemical systems have potential applications in various fields. One potential application is in the fabrication of bioanalytical systems for biomedical applications and DNA detection. These systems can be 3D printed using polymer/carbon and metal electrodes, allowing for rapid prototyping and customizable fabrication in remote areas. Another potential application is in the evaluation of characteristics and degradation of active carbon electrodes, which are used as configuration materials in electric double layer capacitors. Electrochemical technologies can also be applied to remediate environmental problems, such as treating polluted soils and removing hazardous species from industrial liquid wastes. However, despite the promising nature of these technologies, barriers need to be overcome to achieve full-scale applications in industry. Additionally, three-pole electrochemical systems can be integrated into power converters to improve electrical performance and reliability in medium power applications.
What are the security and trust issues in blockchain-based triple-entry accounting?5 answersBlockchain-based triple-entry accounting faces security and trust issues. The use of blockchain technology provides transparency and immutability to transaction records, but it does not ensure the security of data. Cyber threats, both external and internal, pose risks to accounting information security. However, blockchain can be used to enhance accounting cyber security by securing accounting data and preventing malicious activities such as data theft and fraudulent accounting statements. Triple-entry bookkeeping in the blockchain era offers advantages such as automatic transaction validation, increased openness and trust, and fraud prevention. Despite the benefits, the implementation of triple-entry bookkeeping in medium-sized entities and MSMEs is hindered by high costs and a lack of understanding among professional accountants. To address these challenges, support from all parties is needed to develop and implement blockchain-based triple-entry accounting in the financial industry.