The research gap of compost? the limition of compost in agriculture?5 answersThe research gap in composting lies in limited studies on substrate formulation, poor control of operational variables, lack of field-level investigations, technological feasibility of scale-up processes, and economic viability with cost-benefit analysis. Compost limitations in agriculture include the presence of microplastics (MPs) in municipal solid waste (MSW) compost, which act as vectors for toxic contaminants, impacting soil properties and inhibiting plant growth. Additionally, compost application requires technical improvements for optimal effects on soil and crops, with precision farming machinery aiding in the efficient incorporation of compost into the soil, leading to increased biological soil activity over time. Moreover, the use of probiotics in composting can reduce composting time and control odors, enhancing the quality of compost fertilizer.
What's the limition or challenge of compost in agriculture?5 answersComposting in agriculture faces several limitations and challenges. One major challenge is the long duration of composting, which is attributed to materials that take a significant amount of time to decompose, especially during co-composting. Additionally, the emission of undesirable odors during composting adversely affects compost quality, environmental health, and human well-being. The reliance on chemical fertilizers due to composting challenges like pathogen detection, low nutrient status, and odor production has led to environmental issues such as greenhouse gas emissions and soil degradation. Furthermore, the increasing use of chemical fertilizers beyond a certain limit has not resulted in significant crop production increases, highlighting the need for sustainable alternatives like vermicompost to maintain soil fertility and reduce costs. These challenges underscore the importance of improving composting techniques for efficient organic waste management in agriculture.
What is numerical homogenisation?5 answersNumerical homogenization is a computational technique used to simplify complex structures by creating simplified numerical models that accurately represent the mechanical behavior of the original model. It involves reducing large-scale problems to simplified models valid on a target scale of interest, taking into account the impact of smaller-scale features that are not resolved. This methodology has been applied to various fields, including the analysis of composite materials, diffusion processes, and deformation of mechanical structures. It uses homogenization procedures to obtain equivalent responses from representative elements or equations. The goal is to accurately predict the behavior of the entire structure by studying the interaction of its components within a microstructure model. Numerical homogenization methods can handle problems with a continuum of scales and have been successfully applied to various partial differential equations, including elliptic model problems and wave scattering in heterogeneous media.
How can the Suquet limit be used to design cellular materials?5 answersThe Suquet limit can be used to design cellular materials by applying the energy-based criterion of limit states in anisotropic elastic solids. This approach involves analyzing the elastic model of the skeleton and the topological arrangement of the cell structure in cellular materials. By considering the affinity of node displacements in tensile, bending, and shear deformation, the force-displacement relations for the skeleton struts can be determined. The stiffness matrix for a single cell can then be expressed as functions of the compliance coefficients for stretching and bending of struts. By studying the distributions of critical energy density with respect to the change in skeleton stiffness, the elastic limit states of the cellular materials can be predicted. This method allows for the design of cellular materials with desired elastic properties and customizable topologies.
What are the limitationsassociated to wastewater sludge composting?4 answersWastewater sludge composting has several limitations. One limitation is the release of odorous gases during the composting process, which can be a nuisance. Another limitation is the presence of organic pollutants in the sludge, which can limit its land application and pose potential risks. Additionally, the high humidity, low air permeability, and high nitrogen content of sewage sludge can result in low-quality compost. To overcome these limitations, innovative techniques such as the use of structuring agents and additional organic carbon sources have been proposed to improve the composting process and the quality of the final product. It is also important to consider the effects of compost on the soil-plant system and soil biodiversity preservation when disposing of sludge in agriculture.
How is the limit of pi calculated?3 answersThe limit of pi is calculated using various mathematical methods. One approach involves deriving new identities for the limit of the exponential of Pi/8, using Pochhammer symbols and the secant function. Another method involves computing the limit as n → ∞ of the expected value of the minimum 2-factor in a complete bipartite graph, which is conjectured to be twice the value obtained for the minimum travelling salesman tour on the complete graph. Additionally, geometric methods have been used historically to calculate pi, as seen in a textbook published in England in 1707. These methods involve algebraic and numerical techniques that are analyzed in the paper. Overall, the limit of pi can be determined through a combination of mathematical and geometric approaches.