scholarly journals Study of mathematical methods and models usage in the pesticide degradation and residue prediction

Author(s):  
Fang Li ◽  
V.I. Dubovyk ◽  
Runqiang Liu

Pesticide was widely used in agriculture industry to ensure the crops’ yield and quality, followed that pesticide pollution had become one of the most serious issues for public health in the world. Therefore, it’s necessary to develop mathematical models for the prediction of pesticide degradation and residue. In this paper, we introduced four kinds of mathematical models in pesticide prediction, and offered the basis theories and practical applications for each model. Then we compared their advantages and disadvantages systematically by analyzing the roles of each one. Finally, present challenges and future perspectives in pesticide residue prediction fields were discussed.

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 8509-8524
Author(s):  
Zeyu Zhang ◽  
Zheng Fan ◽  
Guoliang Zhang ◽  
Lei Qin ◽  
Jie Fang

In recent years, microbial degradation technology has shown broad potential in the fields of agriculture, industry, and environmental protection. However, in practical applications the technology still encounters many problems, such as low bacterial survivability during dynamic operations, the need to remove bacterial liquid, and low tolerance in high-toxic environments, among other issues. Immobilization technology has been developed to overcome such limitations. Microbial strains have been prepared for a specific range of activities utilizing self-fixation or exosome fixation. Immobilization can significantly improve strain density, toxicity tolerance, and bacterial liquid removal. This review first presents the advantages and disadvantages of the current microbial immobilization technologies and then summarizes the properties and characteristics of various carrier materials. The review focuses on how biomass-derived materials have been used as the carriers in new microbial immobilization technologies. The excellent biocompatibility, unique physical structure, and diversified modification methods of biomass-derived materials have shown excellent prospects in the field of microbial immobilization. Finally, microbial immobilization technologies’ potential applications in agriculture, industry, and environmental applications are considered.


2020 ◽  
Vol 18 (5) ◽  
pp. 259-270
Author(s):  
Janusz Uchmański

Ecology is a branch of biology that deals with the life of plants and animals in their environment. Nature protection are practical actions where ecology is applied. Ecology is the most biological branch of biology because it deals with individuals in their living environment, and individuals "exist" only in biology. The most important issue being considered in ecology is biodiversity: its changes and its persistence. In their research, ecologists focus on the functioning of ecological systems. In classical terms, they assume that the most important mechanism is density dependence. Mathematical models traditionally applied in ecology include ordinary difference and differential equations, which fits well with the assumption of density dependence, but this results in ecology being dominated by considerations of the stability of ecological systems. Evolutionary biology and ecology have separate areas of interest. Evolutionary biology explains the formation of optimal characteristics of individuals. Ecology also takes into account those individuals who have lost in the process of natural selection. The mathematical methods used in classical ecology were developed for the use of physics. The question arises whether they give a precise picture of the dynamics of ecological systems. Recently, a view has emerged stating that in order to see the importance of full-scale biodiversity, we should refer to individuals (rather than population density) as basic "atoms" that make up ecological systems. In ecology, we call this an individual-based approach. However, it gives a very complex picture of how ecological systems work. In ecology, however, there is an alternative way to describe the dynamics of ecological systems, i.e. through the circulation of matter in them and the flow of energy through them. It allows the use of traditional difference and differential equations in the formulation of mathematical models, which has proven itself in practical applications many times.


BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 8509-8524
Author(s):  
Zeyu Zhang ◽  
Zheng Fan ◽  
Guoliang Zhang ◽  
Lei Qin ◽  
Jie Fang

In recent years, microbial degradation technology has shown broad potential in the fields of agriculture, industry, and environmental protection. However, in practical applications the technology still encounters many problems, such as low bacterial survivability during dynamic operations, the need to remove bacterial liquid, and low tolerance in high-toxic environments, among other issues. Immobilization technology has been developed to overcome such limitations. Microbial strains have been prepared for a specific range of activities utilizing self-fixation or exosome fixation. Immobilization can significantly improve strain density, toxicity tolerance, and bacterial liquid removal. This review first presents the advantages and disadvantages of the current microbial immobilization technologies and then summarizes the properties and characteristics of various carrier materials. The review focuses on how biomass-derived materials have been used as the carriers in new microbial immobilization technologies. The excellent biocompatibility, unique physical structure, and diversified modification methods of biomass-derived materials have shown excellent prospects in the field of microbial immobilization. Finally, microbial immobilization technologies’ potential applications in agriculture, industry, and environmental applications are considered.


Author(s):  
A. S. Sverstyuk ◽  
N. O. Kravets ◽  
D. V. Vakulenko

<p>Using information technologies in the process of teaching higher mathematics, information technologies in pharmacy helps to develop students creativethinking and better skills of work in a computer environment. It also provides the higher level of getting knowledge, helps to create and study mathematical models of different phenomena; shows how to use and research mathematical methods. The article deals with advantages and disadvantages of using WolframAlpha while  forming mathematical competence of future pharmacists.</p>


2020 ◽  
Vol 89 ◽  
pp. 20-29
Author(s):  
Sh. K. Kadiev ◽  
◽  
R. Sh. Khabibulin ◽  
P. P. Godlevskiy ◽  
V. L. Semikov ◽  
...  

Introduction. An overview of research in the field of classification as a method of machine learning is given. Articles containing mathematical models and algorithms for classification were selected. The use of classification in intelligent management decision support systems in various subject areas is also relevant. Goal and objectives. The purpose of the study is to analyze papers on the classification as a machine learning method. To achieve the objective, it is necessary to solve the following tasks: 1) to identify the most used classification methods in machine learning; 2) to highlight the advantages and disadvantages of each of the selected methods; 3) to analyze the possibility of using classification methods in intelligent systems to support management decisions to solve issues of forecasting, prevention and elimination of emergencies. Methods. To obtain the results, general scientific and special methods of scientific knowledge were used - analysis, synthesis, generalization, as well as the classification method. Results and discussion thereof. According to the results of the analysis, studies with a mathematical formulation and the availability of software developments were identified. The issues of classification in the implementation of machine learning in the development of intelligent decision support systems are considered. Conclusion. The analysis revealed that enough algorithms were used to perform the classification while sorting the acquired knowledge within the subject area. The implementation of an accurate classification is one of the fundamental problems in the development of management decision support systems, including for fire and emergency prevention and response. Timely and effective decision by officials of operational shifts for the disaster management is also relevant. Key words: decision support, analysis, classification, machine learning, algorithm, mathematical models.


Author(s):  
Yudong Bao ◽  
Linkai Wu ◽  
Yanling Zhao ◽  
Chengyi Pan

Background:: Angular contact ball bearings are the most popular bearing type used in the high speed spindle for machining centers, The performance of the bearing directly affects the machining efficiency of the machine tool, Obtaining a higher value is the direction of its research and development. Objective:: By analyzing the research achievements and patents of electric spindle angular contact bearings, summarizing the development trend provides a reference for the development of electric spindle bearings. Methods:: Through the analysis of the relevant technology of the electric spindle angular contact ball bearing, the advantages and disadvantages of the angular contact ball bearing are introduced, and the research results are combined with the patent analysis. Results:: With the rapid development of high-speed cutting and numerical control technology and the needs of practical applications, the spindle requires higher and higher speeds for bearings. In order to meet the requirements of use, it is necessary to improve the bearing performance by optimizing the structure size and improving the lubrication conditions. Meanwhile, reasonable processing and assembly methods will also have a beneficial effect on bearing performance. Conclusion:: With the continuous deepening of bearing technology research and the use of new structures and ceramic materials has made the bearing's limit speed repeatedly reach new highs. The future development trend of high-speed bearings for electric spindles is environmental protection, intelligence, high speed, high precision and long life.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 259
Author(s):  
Arne Schwelm ◽  
Jutta Ludwig-Müller

Here we review the usefulness of the currently available genomic information for the molecular identification of pathotypes. We focused on effector candidates and genes implied to be pathotype specific and tried to connect reported marker genes to Plasmodiophora brassicae genome information. The potentials for practical applications, current obstacles and future perspectives are discussed.


2020 ◽  
pp. 152808372096827
Author(s):  
Shu Fang ◽  
Rui Wang ◽  
Haisu Ni ◽  
Hao Liu ◽  
Li Liu

Electric heating garment can improve the thermal comfort for people living and working in cold environment. Compared with passive heating materials, electrical heating shows dominant advantages on reusability, controlled temperature, safety and so on. This review article systematically introduced the material preparation, electric-thermal properties, advantages and disadvantages of the existing flexible heating elements, and elaborated the research and application progress of smart garments in detail, providing reference for the research of flexible heating elements and smart garments. And the existing challenges and the possible future perspectives were also discussed.


2020 ◽  
Vol 36 (2) ◽  
pp. 265-310 ◽  
Author(s):  
Morteza Asghari ◽  
Amir Dashti ◽  
Mashallah Rezakazemi ◽  
Ebrahim Jokar ◽  
Hadi Halakoei

AbstractArtificial neural networks (ANNs) as a powerful technique for solving complicated problems in membrane separation processes have been employed in a wide range of chemical engineering applications. ANNs can be used in the modeling of different processes more easily than other modeling methods. Besides that, the computing time in the design of a membrane separation plant is shorter compared to many mass transfer models. The membrane separation field requires an alternative model that can work alone or in parallel with theoretical or numerical types, which can be quicker and, many a time, much more reliable. They are helpful in cases when scientists do not thoroughly know the physical and chemical rules that govern systems. In ANN modeling, there is no requirement for a deep knowledge of the processes and mathematical equations that govern them. Neural networks are commonly used for the estimation of membrane performance characteristics such as the permeate flux and rejection over the entire range of the process variables, such as pressure, solute concentration, temperature, superficial flow velocity, etc. This review investigates the important aspects of ANNs such as methods of development and training, and modeling strategies in correlation with different types of applications [microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO), electrodialysis (ED), etc.]. It also deals with particular types of ANNs that have been confirmed to be effective in practical applications and points out the advantages and disadvantages of using them. The combination of ANN with accurate model predictions and a mechanistic model with less accurate predictions that render physical and chemical laws can provide a thorough understanding of a process.


2006 ◽  
Vol 532-533 ◽  
pp. 333-336 ◽  
Author(s):  
Bok Choon Kang ◽  
Chathura Nalendra Herath ◽  
Jong Kwang Park ◽  
Yong Hwang Roh

Carbon, aramid and glass fibers are inherently superior to conventional textile fibers in terms of mechanical properties and other characteristics. However, each material has its inherent advantages and disadvantages and it is usually recommended to hybridize them to fully benefit of their high performance in practical applications to many products. This paper is concerned with an air texturing process for hybridization of different reinforcement filament yarns. A normal air texturing machine was selected for process development and modified to suit testing purposes. The modified process for hybridization was introduced mainly in terms of air-jet nozzles employed in experiments. With the proposed air texturing process machine, three types of air-nozzle were applied to the experimental work. Three different filament materials were employed in experiments and they are carbon (CF), aramid (AF), and glass (GF). As matrix materials, polyether-ether (PEEK), polyester (PES), and polypropylene (PP) were selected and experimented. Hybrid yarns produced form the proposed process was evaluated optically in terms of bulkiness, arranging, breaking, and mixing, respectively. The experimental results were also summarized in terms of relationships between applied air pressure and yarn count, and variation in count. As a whole, it was concluded from the experiments that the proposed texturing process could be successfully applied to the practical hybridization of different reinforcement filament yarns. It was also revealed from the experiments that the air pressure in the proposed process is not a significant parameter on the pressing in terms of yarn count.


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