numerical characteristic
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Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2273
Author(s):  
Zixue Guo ◽  
Yu Tian ◽  
Xinmei Guo ◽  
Zefang He

To solve the problem of fuzziness and randomness in regional logistics decarbonization evaluation and accurately assess regional logistics decarbonization development, an evaluation model of regional logistics decarbonization development is established. First, the evaluation index of regional logistics decarbonization development is constructed from three dimensions: low-carbon logistics environment support, low-carbon logistics strength and low-carbon logistics potential. Second, the evaluation indexes are used as cloud model variables, and the cloud numerical characteristic values and cloud affiliation degrees are determined according to the cloud model theory. The entropy weight method is used to determine the index weights, and the comprehensive determination degree of the research object affiliated to the logistics decarbonization level is calculated comprehensively. Finally, Beijing-Tianjin-Hebei region is used as an example for empirical evidence, analyzing the development logistics decarbonization and its and temporal variability in Beijing, Tianjin and Hebei provinces and cities. The results of the study show that the development logistics decarbonization in Beijing, Tianjin and Hebei Province has been improved to different degrees during 2013–2019, but the development is uneven. Developing to 2019, the three provinces and cities of Beijing, Tianjin and Hebei still have significant differences in terms of economic environment, logistics industry scale, logistics industry inputs and outputs, and technical support.


Author(s):  
Denis Aleksandrovich Kiryanov

The subject of this research is the problem of incommensurability and the crisis of foundations of the Ancient Greek mathematics. The article describes that the crisis of foundations was caused by the discovery of irrationality by the Pythagorean Hippasus of Metapontum, which resulted in the theoretical instability of mathematics of the Pythagoreans, who believed that everything could be expressed through numbers. The discovery of incommensurable line segments demonstrated that the relations between rational numbers cannot express any variable, for example the diagonal of a square with one side equal to one. Analysis is conducted on the achievements of the Pythagorean School in the field of mathematics. Special attention is given to the role of a number in the philosophy of this school. The article explores the main ways for overcoming this crisis, philosophical explanation of the unfolded situation, based on which the Pythagoreans formulate the methodological ways out of the discovered problem of incommensurability. It is noted that the Pythagoreans were actively elaborating on their philosophy and mathematical apparatus intending to find the answer to the discovery of incommensurability. The author’s special contribution lies in the statement that the discovery of irrationality was not critical for the Pythagoreans: they continued working towards the answer to the problem of incommensurability, as well as refined the mathematical theory of proportions, reconsidered the representation of infiniteness as a certain numerical characteristic of the things and processes. This article is first to advance a hypothesis on the possibility of dividing the object into an infinitely large number of infinitely small parts, which is now understood as the limit of function, which contributes to the development and application of dialectics. The problem of incommensurability led to the creation of new, complex theories in the history of science, culture, architecture, and art.


2021 ◽  
Author(s):  
Tianhua Wu ◽  
Yongtao Gao ◽  
Yu Zhou ◽  
Hao Sun

Abstract The risk prediction of geological disasters exhibits extreme uncertainty and complexity due to the random distribution of evaluation indexes within a finite interval. To improve the accuracy of disaster prediction results, a new evaluation method is in this study suggested to perform a risk evaluation of geological disasters based on multidimensional finite interval cloud model (MFICM) and combination weighting. The MFICM with a transformation between qualitative concept and quantitative data depicts uncertainties and actual distribution features of indexes in the finite interval. Analytic hierarchy process (AHP) and principal component analysis (PCA) are adopted to determine the subjective and objective weights of evaluation indexes, respectively, and the combination weight is calculated by a linear method to reduce the influence of subjective factors. The numerical characteristic parameters of each indexes belonging to various risk levels are first calculated based on established evaluation index system. Subsequently, a multi-dimensional finite interval cloud is generated from a forward cloud generator using MATLAB software. Finally, the comprehensive certainty degrees relative to different levels for each sample are determined combined with combination weight, which achieves a mapping of uncertainty between semantic variables and index values. The proposed method is applied to engineering cases regarding three geological disasters, i.e., water inrush, rock burst and collapse. The obtained results with accuracy and results comparison with reference methods show that the MFICM is verified to be practical and universal for the risk evaluation of geological disasters, which improves and enriches the theoretical framework of geotechnical engineering disaster risk evaluation.


2021 ◽  
Vol 2 (43) ◽  
pp. 78-83
Author(s):  
Anatoliy T. Lebedev ◽  
◽  
Viktor V. Ochinskiy ◽  
Yuriy I. Zhevora ◽  
Ramil’ R. Iskenderov ◽  
...  

When performing various technological operations in crop production, the working bodies of tillage equipment in contact with the soil wear out under the influence of an abrasive environment. (Research purpose) The research purpose is in theoretical substantiation for a method for quantifying the wear capacity of soils with different abrasive characteristics. (Materials and methods) The article presents the evaluation of the abrasive ability of the soil by the wear of a steel rod vertically immersed in the soil and moving translationally. Authors used the standard rod of steel St0; geometric parameters of the worn rod are diameter d = 25-30 millimeters, height h = 250 millimeters; dynamic characteristics during the test are moving speed V = 3 kilometers per hour, distance of movement L = 100 meters. The worn rod sinks to a certain depth, moves in the soil at a constant speed. A device was used to determine the abrasive characteristics of the soil. (Results and discussion) The numerical characteristic of the wear capacity of the soil was determined as the physical value of the wear of the standard worn rod when moving in the soil as A=Q/L, grams per meter. The lower the value of this ratio, the less abrasive components are in the soil; based on the wear data of a standard rod, it is possible to obtain a characteristic of the wear capacity of various soils. (Conclusions) The proposed method allows us to determine the abrasive and wear characteristics of various types of soils. The results of the study make it possible to install working bodies on tillage machines in accordance with the type and wear capacity of the soil in which they will work, which will reduce the cost of their manufacture and increase the efficiency of the use of equipment.


2020 ◽  
Vol 10 (20) ◽  
pp. 7191
Author(s):  
Alexander Paramonov ◽  
Ammar Muthanna ◽  
Omar I. Aboulola ◽  
Ibrahim A. Elgendy ◽  
Riad Alharbey ◽  
...  

Wireless networks connect various devices through radio waves in which the network connection may have different structures. Moreover, the network structure is determined based on the placement areas of the network elements, which can be affected by the building and their locations. However, the numerical characteristic which describe the features of the real environment and allow them to be related to the properties of the model are still a challenge that has not been well addressed. To this end, in this paper, we analyze the modeling problems related to the structure of user placement in the access network. Our proposed solution is based on a description of the user environment structure in which cities in the form of buildings and constructions are considered as a typical environment. We propose a new model for addressing the wireless network structure in an efficient manner in which the features of the environment are considered, which are numerically expressed in the form of the Hurst parameter or fractal dimension. In addition, the fractal dimension, geometric fractals, and the characteristics of the user’s distribution territory and urban development are efficiently utilized. Then, we analyze the influence of the fractal properties of the environment on the structure of promising communication networks; in particular, on the structure of the Internet of Things network. Finally, simulation results proved that the proposed model is considered as a beneficial solution for modeling mobile communication and wireless access networks, including fifth-generation networks.


Author(s):  
Jie Chen ◽  
Guangqiang Wu

Abstract Since impeller shape has great influence on hydraulic performance of a torque converter, a multi-objective optimization method based on non-dominated sorting genetic algorithm II (NSGA-II) has been used to redesign the impeller geometry. Radial basis function (RBF) is attempted to establish the surrogate models for performance responses in impeller design. A sophisticated automotive torque converter case is exemplified, which demonstrates that RBF provides a better surrogate accuracy and NSGA-II is more effective than the other methods studied. To verify the optimization results, the complete numerical characteristic curves of the torque converter with the optimized impeller are compared to the validated numerical characteristic curves of the initial torque converter. The numerical results show that the stall torque ratio and peak efficiency are increased by 3.18% and 1.4%, respectively. The results indicate a reasonable improvement in the optimal design of torque converter impeller and a higher performance using the NSGA-II method.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Wangping Qian ◽  
Taiyue Qi ◽  
Xiao Liang ◽  
Shaojie Qin ◽  
Zongyang Li ◽  
...  

The water-bearing body (WBB) behind tunnel linings has been some of the main causes of damage in operational tunnels. The WBB directly affects the serviceability state of tunnel linings; thus, determining a method to detect this problem is a widely studied issue regarding tunnel maintenance. In this paper, a vehicle-borne transient electromagnetic method (VBTEM) is put forward for the first time to detect WBB behind tunnel linings, and the aim is to fully investigate the transient electromagnetic response and numerical characteristics of the WBB behind tunnel linings. Firstly, the transient electromagnetic response curves of the WBB and surrounding rock are obtained and compared in detail by using the finite element method. Then, taking the distance, thickness, radius, and resistivity of the WBB as variable parameters, the parametric sensitivity rule of the response curve of the WBB is analyzed. Finally, a dimensionless response curve is proposed, a mathematical extraction equation is established, and seven numerical characteristic parameters are proposed and extracted. Based on seven numerical characteristic parameters, the technical parameters of the VBTEM equipment are put forward. The results illustrate that the transient electromagnetic response of the WBB is obviously different from that of surrounding rock. The seven numerical characteristic parameters of the dimensionless curve of the WBB can represent the entire response curve of the WBB. The results reveal that the first time gate of the VBTEM equipment needs to be less than 0.05 μs for short-distance problem, and the time span needs to reach four time spans at least. The research results can provide valuable technical references for the application of VBTEM.


The article reveals a retrospective analysis of the concept of «agrarian territorial system» and clarifies the essence of the concept of "mono-agrarian territorial system". The features of their formation in the theory of social geography have been presented. It has been determined that the issue of research of agrarian territorial systems was actively paid attention by scientists of different branches of knowledge. However, the study of agricultural systems was carried out in the generalization of the behavior of the studied object to the process of monodevelopment. In this case, the digital expression of the process of monodevelopment as the dynamics of absolute data of a certain type, characterizing the highest level of generalization has been presented, as a rule, as an additional characteristic of the object of study. It has been proved that in the normative legal acts of Ukraine defining the essence of the concept of «rural area» there was a disordered heterogeneous, often contradictory conceptual and terminological apparatus. It is characterized by chaos and inconsistency in the process of its use in research and management. The development of rural areas due to the peculiarities of their development as monosystems of different hierarchical level has been considered. The development itself has been outlined as monodevelopment. It has been determined that any numerical characteristic of the territory is the starting point of a specific process of monodevelopment that takes place within it. Even without dynamic data, but comparing the starting points of the various processes of monodevelopment, we can assume how they proceed in the analysed area. Of great importance is the study of monoprocesses (generalized at the regional level) related to the use of natural resources of agricultural production, in particular the analysis of indicators of the value of agricultural products; the cost of agricultural products sold by enterprises; the number of employees in Ukraine in general and in agriculture, forestry and fisheries in particular; use of agricultural products. We proved that for full coverage of the characteristics of rural development is not enough to study the course of a single monoprotsesu within it, or several processes, but it is important to study them against the background of the territorial structure of agricultural systems that will make it possible to understand the nature of their development as mono process and identify features of formation agrarian territorial formations as monosystems. For the first time the category «monoagrarian locality» has been applied and its essence has been revealed.


Purpose. Reveal neo-ecological aspects of transformation the territorial structure of agrarian systems. Methods. The method of generalization has been used in order to identify and study the monoprocesses of development that occur in territorial systems of different hierarchical levels. Results. The retrospective analysis of the concept of «agrarian territorial system» has been evaluated. The essence of the concept of «monoagrarian territorial system» in the context of modern ecological problems had been specified. The peculiarities of the formation of the conceptual and terminological apparatus connected with agrarian monosystems in the theory of social geography have been given. Emphasis had been made on the involvement of scientists in various fields of knowledge in the formation of this apparatus. Attention has been focused on the study of agricultural systems in terms of generalization of their attributes to track the process of mono-development. The digital basis of the process of monodevelopment and the dynamics of absolute data of a certain type, which characterize the highest level of generalization, have been considered, as a rule, as a determinant characteristic of the object of study. The peculiarities of the coverage of the concept of "rural area" in the regulations of Ukraine have been analyzed. The disorder, heterogeneity, and contradiction of the essence of this concept in various normative legal acts have been established, because of which it is inconvenient to use it in all spheres of life of the population, including in the implementation of scientific research. The article analyzes the development of rural areas as monosystems of different hierarchical levels, and the process of their development is outlined as monodevelopment. It had ben noted that any numerical characteristic of the territory can become a starting point for a specific process of monodevelopment that takes place within it. That is, even in the absence of dynamic data, but in the presence of the possibility to compare the starting points of the various processes of development of such monorosystems, we can predict the peculiarities of their course in the study area. The importance of research of monoprocesses (generalized at the regional level) through the analysis of indicators the cost of the made agriculture production had been outlined; the cost of agricultural products sold by enterprises; the number of employees in Ukraine in general and in agriculture, forestry, and fisheries in particular; use of agricultural products. Conclusions. The study proves the need for comprehensive coverage of the peculiarities of rural development focuses on the inadequacy of studying the course of any one monoprocess within them, or even several processes. The importance of studying such processes against the background of the transformation of the territorial structure of agricultural systems operating in the context of neo-globalization challenges has been emphasized. This scientific approach made it possible to understand the essence of the development of rural areas as monosystems and to identify the features of them further in the context of neo-environmental aspects. The conceptual and terminological apparatus in a specific socio-geographical study was first supplemented by the category of "mono-agrarian locality" with the author's interpretation of its essence.


Author(s):  
Victor Zanozin ◽  
Aleksandr Barmin ◽  
Stanislav Yamashkin ◽  
Anatoly Yamashkin

The article presents a methodology for assessing landscape diversity, which allows to obtain a comprehensive numerical characteristic of the geographical environment, integrating the properties of its stability, which determines the characteristics of economic use. The identification and analysis of the landscape diversity of natural-territorial complexes is an urgent task that is in the center of attention of ecological and geographical research. On the basis of digital landscape maps, the results of experimental studies of system relationships of functioning of natural-social-production systems and structural-genetic landscape studies for the first time landscape diversity of the central part of the landscape of the Volga River delta was made. In this paper, we analyzed a number of basic landscape metrics used in assessing landscape diversity for the territory of the central part of the landscape of the Volga River Delta. Among them: the average area of landscape sections, the index of landscape fragmentation, the index of landscape complexity, the coefficient of landscape fragmentation, the index of landscape mosaic, the index of relative wealth, the Menninik index. To create schemes of landscape diversity, the method of nets in the form of hexagons, which is hardly used in domestic landscape mapping, was tested. The study and assessment of the landscape diversity of the indigenous tracts of the central part of the Volga River Delta proves that such a study makes it possible to choose the right decisions when organizing the territory. It takes on leading significance in the justification of economic activity and is a necessary component of design. Studies have shown that the largest number of undisturbed natural territorial complexes is found in areas with a high degree of landscape diversity. Many of them territorially coincide or are close to sites with the status of specially protected natural areas.


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