Application of Sentinel Images 2-A in Estimation of Potassium in Potatoes

Potato production in Indonesia decreased by 2.43% from 1,314,657 in 2019 and 1,282,768 tons in 2020. One of the causes of the decline in potato production is a lack of potassium. Potassium nutrient deficiency can be caused by fertilization that is not yet precise and is still done conventionally. The purpose of this study was to estimate the nutrient content of potassium using Sentinel 2-A. This study observed 50 points that were determined through the free grid method. Sentinel 2-A was transformed into GLI, GNDVI, NDVI which is the vegetation index and NDSI, and SAVI which is the soil index. The results showed that plant K correlated with GLI CS index (r = -0,46), NDVI CS (r = -0,48) and NDSI CS (r = -0,46). NDVI CS (R2 =2 3%) is the most accurate index in estimating the nutrient content of Potassium than GLI CS (R2 = 21%) and NDSI CS (R2 = 21%). Based on the results of the plant K regression test and NDVI CS, the regression equation y = 1,8003 + (-0,5716 NDVI CS) was obtained. The results of the validation test showed that the t table (-3.18) > t count (2.15) so that there is a significant difference in the estimation results of potassium with the results of potassium obtained in the field. Based on the results of the validation test which were significantly different, the productivity estimation model could not be used to estimate the potassium nutrient in potatoes.

A novel second-order adaptive grid method for singularly perturbed convection–diffusion equations

In this paper, a singularly perturbed convection–diffusion equation is studied. At first, the original problem is transformed into a parameterized singularly perturbed Volterra integro-differential equation by using an integral transform. Then, a second-order finite difference method on an arbitrary mesh is given. The stability and local truncation error estimates of the discrete schemes are analyzed. Based on the mesh equidistribution principle and local truncation error estimation, an adaptive grid algorithm is given. In addition, in order to calculate the parameters of the transformation equation, a nonlinear unconstrained optimization problem is constructed. Numerical experiments are given to illustrate the effectiveness of our presented adaptive grid algorithm.

Research on Design of Stalk Furniture Based on the Concept and Application of Miryoku Engineering Theory

Through discussion on the disposal of crop stalks in rural China, where stalks are usually burned in the open air, resulting in the production of a large amount of smoke and air pollution, this study has been conducted to discuss the reasonable and effective use of waste stalks, and to explain the excellent characteristics of stalks from the perspective of green, ecological sustainable design and user perceptual needs, as well as the application of stalks in furniture design. In view of the accuracy of stalks in the design of furniture products, the paper has adopted the evaluation grid method in Miryoku engineering to guide the design practice. In the research process, interviews were first conducted on the basis of sample selection, then based on the expert opinion survey method, eight testers were selected for in-depth interviews. Key words of charm factors were extracted from 190 picture samples, and then a personal evaluation structure map and statistical data were built to construct an overall evaluation structure of the rural style stalk furniture. Next, the score value of the charm factor of stalk furniture was analyzed through the Likert scale questionnaire, the charm factor and specific performance characteristics of the rural style were sorted, followed by a proposed design method. Finally, the effectiveness of the design strategy was verified with the design of stalk furniture in rural style. The study emerged with the feasibility of the design of furniture products made of stalks. The results of the study have shown the correlation between the elements of furniture products and the perceptual image of users. Furthermore, the results have demonstrated the reuse value of waste stalks and improved the innovative design of stalks in the home furnishing field, which conveys the concept of sustainable development.

Mathematical Modelling of the Elliptical Vortex Ring in a Viscous Fluid with the Vortex Filament Method

The article deals with modelling an elliptical vortex ring in a viscous fluid using the Lagrangian vortex filament method. The novelty is that earlier only inviscid flows restricted vortex filament method application. The proposed viscosity model uses an analogue of the diffusion rate method, which is widely applied to simulate plane-parallel and axisymmetric flows of viscous fluid. A transfer of the formula of a diffusion rate from two-dimensional flows to the model of spatial vortex filament is due to assumption that swirling of vortex lines (helicity of vorticity) is unavailable. Despite the laxity of the diffusion rate model for general spatial flows, its application enables taking into account the effect of viscous diffusion of vorticity, which provides expansion of vortex tubes in space. The paper formulates the vortex filament method in which the filaments are broken into the vortex segments. Such discretization enables turning from the equation of vorticity evolution in partial derivatives to a system of ordinary differential equations with respect to the parameters of the segments. Formulas to calculate a filament system-induced flow rate as well as formulas to perform approximate calculation of an analogue of the diffusion rate are given.The objective is to propose the viscosity model as an application to the vortex filament method by the example of modelling the evolution of an elliptical vortex ring in viscous fluid. The calculation results obtained by the vortex method are compared with the existing experiment and with the calculation performed by the grid method in the OpenFOAM package. A feature of the problem is that there are zones of nonzero helicity of vorticity where the proposed model of viscosity, strictly speaking, is not correct. It is shown that the results of calculations are in good agreement with each other and are in complete agreement with experiment. This allows saying that the effects of swirling vortex lines do not significantly affect the results of modelling a specific example of the spatial flow of viscous fluid by the proposed modification of the vortex filament method.

Global carbon emission spatial pattern in 2030 under INDCs: using a gridding approach based on population and urbanization

Purpose The intended nationally determined contributions (INDCs) is a major outcome of the Paris Agreement on international cooperation to reduce emissions, and is likely to be the future scenario for carbon emissions. This paper aims to obtain the fine spatial pattern of carbon emissions in 2030, identify hot spots and analyze changes of carbon emissions with a spatial grid method. Design/methodology/approach Based on the integrated quantified INDCs of each economy in 2030, the authors predict the population density pattern in 2030 by using the statistics of current population density, natural growth rates and differences in population growth resulting from urbanization within countries. Then the authors regard population density as a comprehensive socioeconomic indicator for the top-bottom allocation of the INDC data to a 0.1° × 0.1° grid. Then, the grid spatial pattern of carbon emissions in 2030 is compared with that in 2016. Findings Under the unconditional and conditional scenarios, the global carbon emission grid values in 2030 will be within [0, 59,200.911] ktCO2 and [0, 51,800.942] ktCO2, respectively; eastern China, northern India, Western Europe and North America will continue to be the major emitters; grid carbon emissions will increase in most parts of the world compared to 2016, especially in densely populated areas. Originality/value While many studies have explored the overall global carbon emissions or warming under the INDC scenario, attention to spatial details is also required to help us make better emissions attributions and policy decisions from the perspective of the grid unit rather than the administrative unit.

PARAMETRIC SYNTHESIS OF A MOVING OBJECT STABILIZER

The problem of choosing the variable parameters of a stabilizer of an object which minimize an additive quadratic integral functional reflecting the complex of requirements for a closed stabilization system is considered. To solve the problem a combined method of parametric synthesis of the stabilizer, which is a sequential combination of the Sobol grid method and the Nelder-Mead method, is proposed. At the first stage of the method by applying the Sobolev grid method a working point of the closed system in the pace of its variable parameters is transferred into a neighborhood of the quality functional global minimum point. Then at the second stage the Nelder-Mead method is used to relocated the working point into a small neighborhood of the global minimum. The method proposed comprises a particular algorithm for choosing the weight coefficient of the additive quality functional as well as makes use of the stabilization object state vector main coordinates, which provide the most adequate description of its dynamic features. The properties of a mathematical model of controlled system with discontinuous stabilization process control are studied numerically. The analysis of the plots in the dynamical system state phase space indicates non-spiral approach of the system to its equilibrium state. The synthesized control is realized in the form of a sequence of switchovers.