Mathematical Model For Evaluation Research Articles

Evaluation and application research on thermal comfort of mining face in hot and humid mines

The hot and humid environment in the coal mines negatively affects miners' health and mental health. This paper analyzes the factors that affect the human body heat dissipation, puts forward the concept of dressing rate, and uses the dressing rate to correct the human skin heat dissipation loss and sweat evaporation heat dissipation loss in the underground environment. A human-body thermal comfort model suitable for the hot and humid mine environment is constructed. Then the evaluation index UPMV of thermal comfort in hot and humid mines is proposed, and the mathematical model of human thermal comfort evaluation is constructed which improves the accuracy of human thermal comfort evaluation in hot and humid mines. Lastly, a software system of thermal comfort evaluation for hot and humid mines is developed, which is used to evaluate the thermal comfort of the human body at different working points of horizontal mining roadway in Shoushan mine, and the accuracy of the evaluation model is validated. The research results provide a theoretical basis for the evaluation system of human thermal comfort in hot and humid environments, and provide a reference for a scientific and reasonable arrangement of underground production.

Методичні особливості оцінки рівня компетентності експертів у групі при визначенні ефективності ракетно-космічних комплексів

Expert examination methods greatly facilitate the solution of difficult-to-formalize problems. However, in this case the solution is affected by a subjective factor. The decision-making theory has a number of methodological techniques that diminish its effect on the decision made. This paper presents a method of quantitative evaluation of experts’ competence from the results of an expert examination of the efficiency determination of unique, technically complex systems of special and dual purpose, in particular space-rocket complexes. In an expert examination of projects of such systems, it is suggested that the experts’ competence be quantitatively evaluated in two stages: a preliminary evaluation of the experts’ competence from their factual data and a refined evaluation of the experts’ competence just before the calculation of the expected indices of target efficiency using the results of expert examinations made by the procedure developed. The proposed method of quantitative evaluation of experts’ competence is based on evaluating the qualification of the experts involved in the target efficiency determination of a complex engineering system. A rank matrix constructed on the basis of partial criteria of technical efficiency and additional factors of indirect control is proposed as a tool to eliminate cases where at a high level of expert evaluation consistency the most accurate expert evaluations may be considered anomalous in the expert evaluation of the technical and target efficiency of space-rocket systems. The presented mathematical model of quantitative evaluation of experts’ competence includes parameters that adjust the mathematical model to specific conditions of the expert evaluation (expert evaluation methods employed, measurement scales, specific limitations, etc.). The mathematical model is constructed around the axiom that the “true” estimates of the significance of the objects under evaluation lie within the expert evaluation domain. The paper also presents an enlarged algorithm for adjustment parameter calculation from the results of expert estimate preprocessing. The presented mathematical model and algorithm make it possible to develop a computer program for determining experts’ competence from expert evaluation results.

Technical system for mud loss analysis and diagnosis in drilling engineering to prevent reservoir damage

AbstractMud loss is the most serious formation damage in oil and gas well drilling engineering and is an unsolved technical problem. To prevent mud loss, it is necessary to accurately understand and identify three key factors of mud loss, including the location of the loss, the time of occurrence, and the severity of the loss. The diagnosis of mud loss is a prerequisite for the proper formulation of mud loss control techniques. It emphasizes the integration of predrilling, drilling, and postanalysis information to describe and characterize loss zones and predict potential loss zones. On the basis of the theory of engineering fuzzy mathematics, we develop a mathematical model for loss probability evaluation that combines logging anomaly features and engineering data to predict the location of losses from drilling mud and develop a loss formation identification method. The study of hydraulic fracture deformation through stress‐sensitive experiments and numerical simulations can predict the deformation and severity of loss channels, which can help optimize the loss of circulating material by adding drilling fluid. Loss pressure models have been developed based on mud loss mechanisms, and loss pressure for hydraulic fracture creation, connection, and extension has been studied to help identify loss mechanisms and types. Mud losses can be identified by unusual engineering characteristics, including sudden changes in drilling times, cuttings, and mud logging. Real‐time logging parameters can be used to monitor the loss process and hence predict the loss trend. The framework of loss diagnosis techniques is established, which helps in successful mud loss controlling.

Explorative Study of Developing a Mathematical Model for Evaluating HOTS in the Mathematics Curriculum Operating in the KZN TVET Colleges

This study developed a mathematical evaluation model, attempting to evaluate the capability of the curriculum (N1 to N2 mathematics) to equip students with higher-order thinking skills (HOTS) in the Technical and Vocational Education and Training (TVET) Colleges. The data set was collected at eMnambithi TVET College during March 2022 and October 2022. The two most crucial elements contributing to students attaining HOTS during teaching and learning are the lecturer’s content delivery ability and the curriculum. In that regard, this study began by partially evaluating the lecturer’s content delivery ability using students’ perspectives through a questionnaire. It was found that N1 and N2 mathematics lecturers’ content delivery abilities from the perspective of the students might be adequate. That left the curriculum as the only major contributing factor in a case where students were found to have poor HOTS at eMnambithi TVET College. Then, the SVHIR model (susceptible S(t), vaccinated V(t), healthy H(t), infected I(t), and recovered R(t)) was successfully developed to attempt the evaluation of students’ HOTS. The model indicated poor HOTS in students at eMnambithi TVET College. That ultimately meant that the curriculum might be incapable of equipping students with HOTS, since the lecturers’ content delivery abilities were deemed to be adequate by the participants of this study.

Salt tolerance evaluation and mini-core collection development in Miscanthus sacchariflorus and M. lutarioriparius.

Marginal lands, such as those with saline soils, have potential as alternative resources for cultivating dedicated biomass crops used in the production of renewable energy and chemicals. Optimum utilization of marginal lands can not only alleviate the competition for arable land use with primary food crops, but also contribute to bioenergy products and soil improvement. Miscanthus sacchariflorus and M. lutarioriparius are prominent perennial plants suitable for sustainable bioenergy production in saline soils. However, their responses to salt stress remain largely unexplored. In this study, we utilized 318 genotypes of M. sacchariflorus and M. lutarioriparius to assess their salt tolerance levels under 150 mM NaCl using 14 traits, and subsequently established a mini-core elite collection for salt tolerance. Our results revealed substantial variation in salt tolerance among the evaluated genotypes. Salt-tolerant genotypes exhibited significantly lower Na+ content, and K+ content was positively correlated with Na+ content. Interestingly, a few genotypes with higher Na+ levels in shoots showed improved shoot growth characteristics. This observation suggests that M. sacchariflorus and M. lutarioriparius adapt to salt stress by regulating ion homeostasis, primarily through enhanced K+ uptake, shoot Na+ exclusion, and Na+ sequestration in shoot vacuoles. To evaluate salt tolerance comprehensively, we developed an assessment value (D value) based on the membership function values of the 14 traits. We identified three highly salt-tolerant, 50 salt-tolerant, 127 moderately salt-tolerant, 117 salt-sensitive, and 21 highly salt-sensitive genotypes at the seedling stage by employing the D value. A mathematical evaluation model for salt tolerance was established for M. sacchariflorus and M. lutarioriparius at the seedling stage. Notably, the mini-core collection containing 64 genotypes developed using the Core Hunter algorithm effectively represented the overall variability of the entire collection. This mini-core collection serves as a valuable gene pool for future in-depth investigations of salt tolerance mechanisms in Miscanthus.

Research on the influence of heat release from cement hydration on the mechanical properties of casing

In order to study the influence of cement hydration heat release on the mechanical properties of casing, this paper calculates the wellbore temperature and pressure field based on the mathematical model of steady-state heat conduction of casing-cement ring-formation rock, establishes a mathematical model for the mechanical evaluation of cement hydration heat release and casing interaction, and performs finite element calculation and experimental simulation of the effect of cement hydration heat release on casing loss, and the results show that the results show: Along the axial direction of the wellbore, the maximum stress on the entire cement ring occurs in the lower position of the cement ring, and the maximum deformation on the casing occurs in the middle position. The axial stress variation range of the middle part of the casing is 50MPa, and the strain is 0.12%; The axial stress variation range of the outer ring is 235MPa, and the strain is 0.09%; The circumferential stress of the middle part varies from 500MPa to 0.255%. It is found that the stress and strain in the middle part of cement sheath are large, and yield is prone to occur. Under the action of cement hydration heat release, the long-axis elliptical deformation of (7.15∼31.8) mm occurs in the casing, that is, a large ovality is produced, which weakens the collapse strength of the casing. Two repeated tests showed that under the cement hydration heat release condition at the casing loss position, the temperature change of 60°C caused the increase of axial force of casing column and the increase of annular air pressure, which caused the non-uniform deformation of casing under the composite load of external extrusion and compression axial force.

A Mathematical Model for the Operational Evaluation of the Dynamics of Heat and Mass Exchange in Flash Evaporators

A Mathematical Model for the Operational Evaluation of the Dynamics of Heat and Mass Exchange in Flash Evaporators

The Evaluation and Development of University English Teaching Quality Based on Wireless Network Artificial Intelligence

This study introduces a novel approach to address deficiencies in prior teaching quality assessment systems by establishing a mathematical model for evaluation. Utilizing a neural network trained via a particle swarm optimization algorithm (PSO), the method develops a BP (Backpropagation) model fine-tuned by PSO to capture the intricate relationships among diverse indicators influencing teachers’ teaching quality assessment and resulting evaluations. Empirical findings highlight the effectiveness of artificial neural networks in constructing a comprehensive evaluation framework accommodating a wide spectrum of systematic assessments. This approach not only optimizes teaching methodologies but also augments overall teaching efficacy and the quality of educational delivery in a holistic manner. Moreover, it fosters the cultivation of multifaceted individuals proficient in English application skills, contributing to the development of high-quality talent in practical and complex domains. The convergence of advanced mathematical modeling techniques and computational methods, alongside the utilization of numerous indicators, aligns with combinatorial principles, exploring the permutations and relationships of diverse factors impacting teaching quality assessment.

Retracted: Mathematical Model of Quantitative Evaluation of Financial Investment Risk Management System

Retracted: Mathematical Model of Quantitative Evaluation of Financial Investment Risk Management System

Процессный подход к управлению затратами и его роль в эволюционном реинжиниринге бизнес-процессов

The aim of the paper is to investigate the role of the process approach to cost management in the evolutionary reengineering of business processes and to develop tools for its implementation. To achieve the specified goal, the following tasks were set in this work: analyze the essence of the process-oriented cost management approach and its connection to business process reengineering; present an algorithm for implementing the process-oriented cost management approach with the aim of subsequent business process reengineering; develop a mathematical toolkit that describes the essence of the approach and allows evaluating the effective-ness of the process-oriented cost management from the perspective of optimizing business processes. As a result of the study, the key aspects of the identified approach and its applicability for the implementation of evo-lutionary reengineering of business processes were highlighted, the main advantages and limitations of this type of activity were characterized. The algorithm is presented and a mathematical model of implementation and performance evaluation of the process approach to cost management with subsequent reengineering of business processes is developed.

Evaluation Model Based On Optimized EWM Identifying Light Pollution

Light pollution has negative impacts on wildlife, human health and the environment, disturbing the natural darkness of the night sky. However, there lacks an objective and feasible method measuring the risk level of light pollution. Therefore, we establish a mathematical evaluation model based on the integration of optimized EWM and TOPSIS to measure the light pollution of representative locations. According to the results, we conclude that the risk level of light pollution is positively correlated to the prosperity of commerce.

Investigation of Spatial Symmetry Error Measurement, Evaluation and Compensation Model for Herringbone Gears

In the machining process for herringbone gears manufactured by numerical control gear-shaping machines, out-of-tolerance problems of symmetry error generally exist. This paper proposed a high-precision control of spatial symmetry error in the one-time forming machining for herringbone gear. To improve the machining symmetry accuracy and quality of herringbone gear, a mathematical model of measurement, evaluation and compensation for spatial symmetry error was established based on the least square method. Meanwhile, a new shaping machining method based on spatial symmetry error detection and compensation was proposed. The test results indicated that the proposed method can maintain symmetry within 0.02 mm. This study provided a novel spatial symmetry error detection and compensation machining method for herringbone gear that has advantages compared to traditional methods in terms of machining accuracy, efficiency, and continuous machining type.

An ecological reserve evaluation and site selection model based on AHP method and cluster analysis

On September 22, 2020, the Chinese government proposed in the 75th United Nations General Assembly that "China will strive to reach peak carbon by 2030 and achieve carbon neutrality by 2060." Adhering to the concept that green water and green mountains are priceless treasures, environmental protection and natural restoration are put in the first place. It is of practical significance to study ecological protection construction and its environmental impact assessment. In this paper, we focus on the impact evaluation of the ecological protection construction of the Seyhanba Forest, based on the mining and analysis of the collected official data and with the help of spss and other software, we give the evaluation model of the impact of Seyhanba on the environment before and after restoration, the mathematical model of the impact evaluation of Seyhanba on the ability of Beijing to resist sandstorms, and the mathematical model of other areas in China that need to build ecological reserves, and extend to the Asia-Pacific region. Mathematical models were provided for the construction of ecological reserves in other countries.

FORECASTING VOLUMES OF ACCUMULATED WASTE

Problem statement. The task of assessing the volume of accumulated waste in the territory of the Dnipropetrovsk region, which is constantly increasing, occupying a larger area and causing damage to the environment, is under consideration. To solve this forecasting problem, it is necessary to create a regression mathematical model for statistical evaluation and analysis of the factor variables’ influence to the total volume of accumulated waste. The purpose of the article. Creation of a mathematical model for forecasting assessment of possible volumes of accumulated waste in the territory of the Dnipropetrovsk region by adjusting the volumes of factor variables. Methodology. Analysis of the dynamics of changes in the volumes of generated, utilized, incinerated, removed waste and capital investments and costs for waste management and establishment of trends in their changes based on descriptive statistics. Application of correlation analysis methods to establish the most statistically significant relationships between factor variables and the resulting feature. The use of regression analysis methods to obtain the coefficients of the regression mathematical model and statistical indicators that explain the probability of the significance of these coefficients. Scientific novelty. A multiple regression mathematical model was developed, which takes into account the factor variables affecting the process of waste accumulation in the territory of the Dnipropetrovsk region. Practical value. The developed regression mathematical model makes it possible to estimate the required amount of investment and forecast the amount of current costs to adjust the total amount of accumulated waste. Conclusions. A mathematical model was created to analyze the volume of accumulated waste in the territory of the Dnipropetrovsk region. Based on this model, the volumes of accumulated waste were calculated. The average value of the relative error of the calculated data is 1.03 %, while the maximum value of the error is 1.97 %, which confirms the adequacy of the developed mathematical model.

A quantitative approach for sealing capacity evaluation of caprock in candidate of aquifer gas storage.

The gas sealing capacity of caprock (SCC) is one of the key factors that determine whether aquifer trap can be constructed into underground gas storage (UGS). However, no standard protocol for evaluating SCC of candidate aquifers has been proposed. Based on the core observation, laboratory experiment, and well logging data, the sealing capacity of the target aquifer caprock of Permian mudstone in D5 block of Litan sag, China, is quantitatively evaluated. The important parameters of mineral brittleness, permeability, breakthrough pressure (BP), mechanical brittleness, thickness, and areal extent that affect the SCC are determined. The results of specific tests and data statistics show that the caprock of D5 block is a low permeability rock with a permeability of 10-4 mD, and the BP of undisturbed rock is greater than 38MPa. Although the brittle mineral quartz is abundant with an average of 38.38%, the mechanical brittleness is not strong under formation conditions. The direct caprock has a thickness of greater than 50m, and on the top of it is a high-quality indirect caprock that complements the physical closure. The results of a mathematical evaluation model show that except for the sealing index of sample 2, all the other samples have optimal sealing capacity. The field interference test shows that the optimal sealing capacity of the caprock meets the requirements of the construction of underground gas storage (UGS). The rationality of the comprehensive evaluation model can provide a reference for similar evaluation projects in the future.

Research on input-output evaluation index of high energy consumption main transformer transformation

In order to quantify the input-output evaluation index of high-energy consumption main transformer transformation projects of power grid enterprises, to provide a real, effective, and quantitative basis for investment decisions, the project input and output indexes are measured from the whole life cycle perspective. The whole life cycle cost, including the initial investment and annual operational maintenance cost, is selected as the input evaluation index, and the four dimensions of safety, economics, efficiency, and greenness are considered. The output evaluation index is proposed, combined with the investment effectiveness of typical projects of production technology reform, the potential output analysis indexes under each dimension are sorted out, the full set of output evaluation indexes of production technology reform projects is constructed, the corresponding characteristic indexes of high energy consumption main transformation projects are selected from the full set of indexes, and mathematical evaluation model of input-output analysis of high energy consumption main transformation projects is built. Verify the model through practical engineering examples.

An extended ITL-VIKOR model using triangular fuzzy numbers for applications to water-richness evaluation

Jiaozuo coalfield is the most typical in Northern China type coalfield. When it mined the Permian coal seams, it was threatened by water inrush from the confined aquifer of thin karst fissure limestone in the lower Carboniferous. How to scientifically evaluate and predict the water-richness of thin karst fissure limestone in Carboniferous system has become the most important work in mine water control and prevention. Taking the mining of coal seam No. 21 of Shanxi Formation in Guhanshan coal mine as an example, this paper analyzed the water-richness main controlling factors of L8 Limestone Aquifer of Taiyuan Formation, and selected four evaluation indexes, i.e. water inflow of drilling, the thickness of L8 Limestone Aquifer, the water level of L8 Limestone Aquifer and fault fractal dimension. The 2-tuple linguistic weights of all factors were obtained by the use of interval 2-tuple linguistic method extended by triangular fuzzy numbers. Following the above outlines, the mathematical model for the 2-tuple linguistic evaluation of water-richness was established based on ITL-VIKOR method extended by triangular fuzzy numbers. The data of geophysical exploration were collected to test the accuracy of the model. In addition, the results of 2-tuple linguistic assessment of water-richness and geophysical exploration were used to evaluate the water-richness of L8 Limestone Aquifer, which extends the evaluation and prediction of water abundance for karst fractured aquifers to dyadic array. These results have been applied to guide the safe mining in Guhanshan coal mine, and will be further extended to the mines with similar geological conditions. It is our goal to establish an intelligent application system to ensure safe production in coal mines, which is great beneficial to the technical personnel engaged in mine water prevention and control.

The impact of patent quality on corporate performance in the context of big data and the Internet of Things

In the context of big data and the Internet of Things, this article explores the impact of corporate patent quality on corporate performance through analysis of corporate patent quality. Starting from multiple influencing factors, measure the patent value of enterprises to promote the economic benefits. Focus on the analysis of the practical conversion capacity of patents and the impact on corporate performance, establish a mathematical evaluation model, and explore the specificity of the patent quality through the method of regression analysis. This article has studied the important role of patent technology to improve the efficiency of enterprises, and explores the overall level of corporate performance management on how to maximizes the overall level of corporate performance management. The system of measures for patent technology to promote performance development under the background of big data constructed by the research has a very good reference for the sustainable development of enterprises at the current stage. From the existing research results, there are problems such as too few analysis samples and slow data updates, and these problems have been better solved in this study. The research analyzes the comprehensive impact of patent quality on enterprises through big data, highlights the positive relationship between patent quality and enterprise performance, and effectively fills the gap in current research.

The mathematical model of ecological carrying capacity evaluation in the water source area of Haikou tidal flat habitat

The mathematical model of ecological carrying capacity evaluation in the water source area of Haikou tidal flat habitat

Mathematical Model for Evaluation of Tumor Response in Targeted Radionuclide Therapy with 211At Using Implanted Mouse Tumor.

Recent introduction of alpha-emitting radionuclides in targeted radionuclide therapy has stimulated the development of new radiopharmaceuticals. Preclinical evaluation using an animal experiment with an implanted tumor model is frequently used to examine the efficiency of the treatment method and to predict the treatment response before clinical trials. Here, we propose a mathematical model for evaluation of the tumor response in an implanted tumor model and apply it to the data obtained from the previous experiment of 211At treatment in a thyroid cancer mouse model. The proposed model is based on the set of differential equations, describing the kinetics of radiopharmaceuticals, the tumor growth, and the treatment response. First, the tumor growth rate was estimated from the control data without injection of 211At. The kinetic behavior of the injected radionuclide was used to estimate the radiation dose profile to the target tumor, which can suppress the tumor growth in a dose-dependent manner. An additional two factors, including the time delay for the reduction of tumor volume and the impaired recovery of tumor regrowth after the treatment, were needed to simulate the temporal changes of tumor size after treatment. Finally, the parameters obtained from the simulated tumor growth curve were able to predict the tumor response in other experimental settings. The model can provide valuable information for planning the administration dose of radiopharmaceuticals in clinical trials, especially to determine the starting dose at which efficacy can be expected with a sufficient safety margin.