scholarly journals Forecasting the parameters of building structures using regression equations. Part 1. Forecasting with independent action of variables and constancy of operating factors

Author(s):  
A. G. Chernykh ◽  
◽  
Sh. M. Mamedov ◽  
D. I. Korolkov ◽  
◽  
...  

The article presents a method for forecasting the parameters of building structures using regression equations. The most commonly used regression equations were used, namely, linear, polynomial, power, exponential, exponential, logarithmic, semi-logarithmic, hyperbolic and logistic ones. The authors propose to use one-factor regression equations in which the variable value is time, and the dependent value is the parameter of the building structure, the changes of which the researcher needs to determine. Thereafter, the authors present the basic equations as multi-factorial ones. This is achieved by means of replacing the coefficients of the main equation with regression equations which are obtained after carrying out a series of tests with variable values of the selected input parameters (such as environmental conditions, material of construction, etc.). Regression equations are derived for each state, and, as a result, a number of parameter values for the basic regression equations are available. Then, a repeated regression analysis is carried out and a regression equation is set up for the coefficients of the main regression equation, which depends on the value of the specified parameters. Such equations are called secondary equations. Examples are given for conditional linear regression, where it is demonstrated how the coefficients of the main regression equation are replaced and what final form the equation achieves after replacing the coefficients with secondary equations. The presented method allows, in the case of expression from the basic equation of the time parameter, to forecast the residual resource, with a large number of parameters of building structures determined.

2020 ◽  
Vol 2 (7) ◽  
pp. 91-99
Author(s):  
E. V. KOSTYRIN ◽  
◽  
M. S. SINODSKAYA ◽  

The article analyzes the impact of certain factors on the volume of investments in the environment. Regression equations describing the relationship between the volume of investment in the environment and each of the influencing factors are constructed, the coefficients of the Pearson pair correlation between the dependent variable and the influencing factors, as well as pairwise between the influencing factors, are calculated. The average approximation error for each regression equation is determined. A correlation matrix is constructed and a conclusion is made. The developed econometric model is implemented in the program of separate collection of municipal solid waste (MSW) in Moscow. The efficiency of the model of investment management in the environment is evaluated on the example of the growth of planned investments in the activities of companies specializing in the export and processing of solid waste.


Author(s):  
Amin Hosseini ◽  
Touraj Taghikhany ◽  
Milad Jahangiri

In the past few years, many studies have proved the efficiency of Simple Adaptive Control (SAC) in mitigating earthquakes’ damages to building structures. Nevertheless, the weighting matrices of this controller should be selected after a large number of sensitivity analyses. This step is time-consuming and it will not necessarily yield a controller with optimum performance. In the current study, an innovative method is introduced to tuning the SAC’s weighting matrices, which dispenses with excessive sensitivity analysis. In this regard, we try to define an optimization problem using intelligent evolutionary algorithm and utilized control indices in an objective function. The efficiency of the introduced method is investigated in 6-story building structure equipped with magnetorheological dampers under different seismic actions with and without uncertainty in the model of the proposed structure. The results indicate that the controller designed by the introduced method has a desirable performance under different conditions of uncertainty in the model. Furthermore, it improves the seismic performance of structure as compared to controllers designed through sensitivity analysis.


2018 ◽  
Vol 51 (4) ◽  
pp. 1059-1068 ◽  
Author(s):  
Pascal Parois ◽  
James Arnold ◽  
Richard Cooper

Crystallographic restraints are widely used during refinement of small-molecule and macromolecular crystal structures. They can be especially useful for introducing additional observations and information into structure refinements against low-quality or low-resolution data (e.g. data obtained at high pressure) or to retain physically meaningful parameter values in disordered or unstable refinements. However, despite the fact that the anisotropic displacement parameters (ADPs) often constitute more than half of the total model parameters determined in a structure analysis, there are relatively few useful restraints for them, examples being Hirshfeld rigid-bond restraints, direct equivalence of parameters and SHELXL RIGU-type restraints. Conversely, geometric parameters can be subject to a multitude of restraints (e.g. absolute or relative distance, angle, planarity, chiral volume, and geometric similarity). This article presents a series of new ADP restraints implemented in CRYSTALS [Parois, Cooper & Thompson (2015), Chem. Cent. J. 9, 30] to give more control over ADPs by restraining, in a variety of ways, the directions and magnitudes of the principal axes of the ellipsoids in locally defined coordinate systems. The use of these new ADPs results in more realistic models, as well as a better user experience, through restraints that are more efficient and faster to set up. The use of these restraints is recommended to preserve physically meaningful relationships between displacement parameters in a structural model for rigid bodies, rotationally disordered groups and low-completeness data.


2011 ◽  
Vol 688 ◽  
pp. 66-87 ◽  
Author(s):  
Efrath Barta

AbstractThe flow regime in the vicinity of oscillatory slender bodies, either an isolated one or a row of many bodies, immersed in viscous fluid (i.e. under creeping flow conditions) is studied. Applying the slender-body theory by distributing proper singularities on the bodies’ major axes yields reasonably accurate and easily computed solutions. The effect of the oscillations is revealed by comparisons with known Stokes flow solutions and is found to be most significant for motion along the normal direction. Streamline patterns associated with motion of a single body are characterized by formation and evolution of eddies. The motion of adjacent bodies results, with a reduction or an increase of the drag force exerted by each body depending on the direction of motion and the specific geometrical set-up. This dependence is demonstrated by parametric results for frequency of oscillations, number of bodies, their slenderness ratio and the spacing between them. Our method, being valid for a wide range of parameter values and for densely packed arrays of rods, enables simulation of realistic flapping of bristled wings of some tiny insects and of locomotion of flagella and ciliated micro-organisms, and might serve as an efficient tool in the design of minuscule vehicles. Its potency is demonstrated by a solution for the flapping of thrips.


2018 ◽  
Vol 76 ◽  
pp. 108-118 ◽  
Author(s):  
Elizabeth Montero ◽  
María-Cristina Riff ◽  
Nicolás Rojas-Morales

Radiocarbon ◽  
2012 ◽  
Vol 54 (3-4) ◽  
pp. 391-406 ◽  
Author(s):  
Hendrik J Bruins ◽  
Johannes van der Plicht ◽  
Mordechai Haiman

Traditional archaeological approaches in the central Negev Desert used to employ excavation techniques in post-prehistoric periods in which stratigraphy is based on architecture, while material culture forms the basis for dating assessment and chronology. Such an approach was understandable, as it focused on the most visible remains of past human habitation. However, the detailed habitation record is in the soil rather than in the walls. Moreover, ceramics and stone tools in desert cultures often have limited time resolution in terms of absolute chronology. The rural desert site of Horvat Haluqim in the central Negev yielded 2 habitation periods with the traditional methodology: (1) Roman period, 2nd–3rd centuries CE; (2) Iron Age IIA, 10th century BCE. We have conducted at Horvat Haluqim initial excavations in small building remains that were never excavated before. Our excavation methodology focuses on detailed examination of the archaeological soil in building structures, coupled with accelerator mass spectrometry (AMS) radiocarbon dating for chronology, and micromorphology of undisturbed soil samples to study stratigraphy and soil contents at the microscopic scale. Here, we report preliminary results, concentrating on the 14C dates. These suggest a much longer habitation history at the site during the Iron Age. The 14C dates obtained so far from these building remains cover Iron Age I, II, III, and the Persian period. The oldest calibrated date (charred C4 plants) in a rectangular building structure (L100) is 1129–971 BCE (60.5%, highest relative probability). The youngest calibrated date in a round building structure (L700) is 540–411 BCE (57.9%, highest relative probability). This excavation methodology provides additional “eyes” to look at past human habitation in the Negev Desert, seeing more periods and more detail than was possible with traditional schemes and ceramic dating.


2003 ◽  
Vol 48 (2) ◽  
pp. 227-232
Author(s):  
Vesna Jablanovic

The basic aims of this paper are: firstly, to set up an endogenous model of food production per capita and population; secondly, to estimate the food production per capita regression equation and population regression equation; and thirdly, to determine stability properties of food production per capita and population in Asia during the period 1967-1997. Empirical content of this model confirms the fact that movement of food production per capita and population had unstable character in Asia in the observed period.


Author(s):  
Nur Mujaddidah Mochtar

Background: There are various circumstances where measurements are not actually possible, replacement parameters can be used to estimate body height. Many characteristics of body height measurement and how to measure it. These include anthropometric measurements that can be used for the identification of medicolegal-forensic processes. Body height in clinical medicine and in the field of scientific research can be easily estimated using various anthropometric parameters such as arm span, knee height, foot length and foot breadth, and others. The arm span and foot length has proved to be one of the most reliable predictors. This study was conducted to estimate of body height from arm span and foot length using the regression equation and to determine the correlation between the body height and arm span and foot length.Methods: This study was conducted at Universitas Muhammadiyah Surabaya with 182 Javanese female students. Stature, arm span and foot length measured directly using anthropometric technique and measuring tape. The data obtained were then analyzed with SPSS version 16. The regression equation was derived for the estimate of body height and the relationship between stature, arm span and foot length determined by the Pearson correlation.               Results: We found that the mean body height of Javanese women was 1534,45 ± 47,623  mm, mean of arm span 1543,25 ± 60,468 mm and the mean of foot length 226,14 ± 9,586 mm. The correlation between stature and arm span was positive and significant (r = 0,715  , p <0,05). The correlation between stature and foot length was positive and significant (r = 0,726 , p <0,05). The correlation between stature and arm span and foot length was positive and significant (r = 0,798, p <0,05).               Conclusion: Body height correlates well with the arm span and foot length so that it can be used as a reliable marker for high estimates using regression equations.


2020 ◽  
Author(s):  
Ludmila Anipko ◽  
◽  
Irina Klimovych ◽  

Anti-crisis analytical procedures the financial stability of trade enterprises (hereinafter – AP FS) are part of the internal financial audit of economic activity. The system of financial monitoring is practically acceptable for the implementation of AP FS. The developed classification allows to determine the ability of the enterprise to implement AP FS. An analytical method has been developed that allows, based on the analysis of the financial condition and multivariate forecast, to develop measures to ensure the financial stability of the trade enterprise continuously. By interpolation, the study of the current financial situation, and extrapolation – a multivariate forecast, the numerical value of the integrated (complex) indicator that characterizes financial stability is determined by the regression equation, including factors listed in the classification, the significance of which is determined by regression equations. Based on the analysis of the numerical values of the regression coefficients, it is possible to determine the most important factors that affect the financial stability of trade enterprises, and those that have almost no effect on it. Components with significantly small numerical values of the regression coefficients can be generally discarded. This will reduce the number of indicators that affect financial stability and thus, you can reduce the number of components in the regression equation to the two three most important, which allows you to solve the problem of optimization. The expediency of using integrated and complex indicators is shown. The obtained results are only an information basis for the economic administration of the trade enterprise in making management decisions, the formation of long-term plans. The developed approaches to assessing the financial stability of enterprises are universal and can be used for enterprises in other sectors of the economy.


2012 ◽  
Vol 588-589 ◽  
pp. 2069-2073
Author(s):  
Jing Ma ◽  
Jun Zhao ◽  
Yu Ling Zhao

A building structure is analyzed using finite element method. The stresses and strains of the structure are calculated numerically, when the foundation subsides unevenly. Thus, the effect of the sedimentation is evaluated. The results can be referenced in the evaluation of building structures.


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