scholarly journals Cable Force Identification Based on Bending Waves in Substructures

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Jing Huang ◽  
Jun Xiao ◽  
Jinxiang Zhang ◽  
Fanying Jiang ◽  
Yang Dai ◽  
...  
Keyword(s):  
Least Squares Method ◽  
External Disturbance ◽  
Sampling Point ◽  
Frequency Method ◽  
Force Identification ◽  
Bending Waves ◽  
Axial Tension ◽  
Cable Force ◽  
The Impact ◽  
Bending Wave

A method is proposed to study the dynamic characteristics of cable structures from the perspective of traveling waves based on the modified Timoshenko beam axial tension model. Considering the propagation characteristics of the bending wave in a beam structure, once the frequency response of the three measuring points is measured, the wave component coefficients can be obtained by the least squares method, and then the cable force and bending stiffness can be identified with the aim of minimizing the fitting residual. The accuracy of this method is verified by a numerical simulation experiment of the cable vibration. Compared with the traditional frequency method, this method focuses on the cable force identification of the substructure, so the effect of the shock absorber is invalid. Moreover, the cable force of each position of the cable can be calculated reversely by static analysis with the identified cable force of the substructure, which breaks the concept that the cable force is a single value. Furthermore, the cable force can be identified at each frequency sampling point, reducing the impact of the external disturbance.

scholarly journals Robust Position Control of a Two-Sided 1-DoF Impacting Mechanical Oscillator Subject to an External Persistent Disturbance by Means of a State-Feedback Controller

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Firas Turki ◽  
Hassène Gritli ◽  
Safya Belghith
Keyword(s):  
State Feedback ◽  
Position Control ◽  
External Disturbance ◽  
Feedback Controller ◽  
Linear Matrix ◽  
Stability Conditions ◽  
Mechanical Oscillator ◽  
Impact Oscillator ◽  
State Feedback Controller ◽  
The Impact

This paper proposes a state-feedback controller using the linear matrix inequality (LMI) approach for the robust position control of a 1-DoF, periodically forced, impact mechanical oscillator subject to asymmetric two-sided rigid end-stops. The periodic forcing input is considered as a persistent external disturbance. The motion of the impacting oscillator is modeled by an impulsive hybrid dynamics. Thus, the control problem of the impact oscillator is recast as a problem of the robust control of such disturbed impulsive hybrid system. To synthesize stability conditions, we introduce the S-procedure and the Finsler lemmas by only considering the region within which the state evolves. We show that the stability conditions are first expressed in terms of bilinear matrix inequalities (BMIs). Using some technical lemmas, we convert these BMIs into LMIs. Finally, some numerical results and simulations are given. We show the effectiveness of the designed state-feedback controller in the robust stabilization of the position of the impact mechanical oscillator under the disturbance.

scholarly journals Behavioral Parameters of Planarians (Girardia tigrina) as Fast Screening, Integrative and Cumulative Biomarkers of Environmental Contamination: Preliminary Results

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1077
Author(s):  
Ana M. Córdova López ◽  
Althiéris de Souza Saraiva ◽  
Carlos Gravato ◽  
Amadeu M. V. M. Soares ◽  
Renato Almeida Sarmento
Keyword(s):  
Water Samples ◽  
Feeding Rate ◽  
Anthropogenic Activities ◽  
Behavioral Responses ◽  
Freshwater Ecosystems ◽  
Sampling Point ◽  
Total Chloride ◽  
Fast Screening ◽  
Sampling Points ◽  
The Impact

The present study aims to use behavioral responses of the freshwater planarian Girardia tigrina to assess the impact of anthropogenic activities on the aquatic ecosystem of the watershed Araguaia-Tocantins (Tocantins, Brazil). Behavioral responses are integrative and cumulative tools that reflect changes in energy allocation in organisms. Thus, feeding rate and locomotion velocity (pLMV) were determined to assess the effects induced by the laboratory exposure of adult planarians to water samples collected in the region of Tocantins-Araguaia, identifying the sampling points affected by contaminants. Furthermore, physicochemical and microbiological parameters, as well as the presence of inorganic compounds (dissolved aluminum, total barium, total chloride, dissolved iron, total fluoride, total manganese, nitrates, nitric nitrogen, total sulfate, total zinc) and surfactants, were determined on each specific sampling point. The behavioral biomarkers (feeding rate and pLMV) of the freshwater planarians were significantly decreased when organisms were exposed to water samples from four municipalities (Formoso do Araguaia, Lagoa da Confusão, Gurupi and Porto Nacional), sites of the Tocantins-Araguaia hydrographic region—TAHR. Both behavioral biomarkers decreased up to ~37–39% compared to organisms in ASTM medium only. Our results showed that these behavioral biomarkers can be used for fast screening monitoring of environmental samples of freshwater ecosystems, since a decrease in feeding rate and locomotor activity was observed in sites impacted by anthropogenic activities. However, the absence of effects observed in some sampling points does not represent the absence of contamination, since several other classes of contaminants were not determined. In these negative results, the absence of deleterious effects on behavioral biomarkers might only be indicative that the potential presence of contaminants on such sites does not significantly affect the performance of planarians. This fast screening approach seems to be useful to determine contaminated sites in freshwater ecosystems for biomonitoring purposes. This knowledge will help to develop biomonitoring programs and to decide appropriate sampling sites and analysis.

Does corporate social responsibility affect dividend policy? Empirical evidence in the French context

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Olfa Ben Salah ◽  
Anis Ben Amar
Keyword(s):  
Corporate Social Responsibility ◽  
Panel Data ◽  
Social Responsibility ◽  
Dividend Policy ◽  
Least Squares Method ◽  
Positive Impact ◽  
Alternative Measure ◽  
Content Type ◽  
Corporate Social ◽  
The Impact

Purpose The purpose of this paper is to focus on the impact of corporate social responsibility (CSR) on dividend policy in the French context. In addition, the authors seek to determine if the individual components of CSR influence dividend policy. Design/methodology/approach This study uses panel data methodology for a sample of French non-financial firms between 2008 and 2018. Generalized least squares method is used to estimate the models. Findings Using panel data methodology for a sample of 825 observations for the period 2008–2018, this study finds a positive impact of CSR practices on dividend policy. The authors also find that individual components of CSR positively influence dividend policy. To check the robustness of the results, this study further runs a sensitivity tests, including an alternative measure of dividend policy, all of which confirm the findings. Practical implications This study has examined the impact of CSR on dividend policy in France and may have implications for regulatory, investors, analysts and academics. First, the involvement in CSR best practices encourages companies to pay more dividends to investors. Therefore, investors are more motivated to invest in socially responsible firms than socially irresponsible firms. Second, given the association of CSR with the quality of accounting information and financial markets, regulators should step up recommendations relating to the different societal dimensions of CSR. Originality/value While little previous work has focused on the causal link between CSR and dividend policy, this research is the first, to the authors’ knowledge, to have looked at the impact of CSR on dividend policy in France.

Incorporating Compressional and Shear Wave Types Into Fuzzy Structure Models for Plates

1995 ◽  
Author(s):  
Judith L. Rochat ◽  
Victor W. Sparrow
Keyword(s):  
Thin Plate ◽  
Shear Waves ◽  
Wave Theory ◽  
Structure Theory ◽  
Detailed Knowledge ◽  
Bending Waves ◽  
Incident Plane ◽  
Dependent Mass ◽  
Mass Spring ◽  
Bending Wave

Abstract Although realistic complex structures are usually difficult to model theoretically, fuzzy structure theory enables one to produce such a model without a detailed knowledge of the entire structure. Using the theory established by Pierce et al. [A. D. Pierce, V. W. Sparrow, and D. A. Russell, J. Vib. Acoust. (to be published), also ASME 93-WA/NCA-17.] regarding fundamental structural-acoustic idealizations for structures with imprecisely known or fuzzy internals, the effects that fuzzy attachments have on different wave types in a primary (or master) structure are examined in this paper. In the theory by Pierce et al., the primary structure that undergoes vibrations is a thin plate mounted in an infinite baffle. On one side of the plate are fuzzy attachments, represented as an array of attached mass-spring-dashpot systems, which are excited by an incident plane pulse. This known theory explains the effects of these attachments on bending waves in the plate. In this paper, the theory is extended to isolated compressional and shear waves in a plate. While studying this new problem, it is discovered that coupling effects occur when the plate and attachment properties are not uniform in the direction perpendicular to the wave propagation. Hence, unlike the bending wave theory which models a finite thin plate with point attached oscillators, the new wave type theory uses a thin plate infinite in one direction with line attached oscillators also infinite in the same direction. For both the compressional and shear waves, it is found that the fuzzy attachments add an apparent frequency dependent mass and damping to the plate. These results are similar to those for the bending wave theory.

scholarly journals The Impact of Public Debt on the Economic Growth of Jordan: An Empirical Study (2000- 2015)

2017 ◽  
Vol 6 (2) ◽  
pp. 114 ◽  
Author(s):  
Tawfiq Ahmad Mousa ◽  
Abudallah. M. LShawareh
Keyword(s):  
Economic Growth ◽  
Empirical Study ◽  
Regression Model ◽  
Least Squares ◽  
Public Debt ◽  
Least Squares Method ◽  
Negative Impact ◽  
External Debt ◽  
Using Data ◽  
The Impact

In the last two decades, Jordan’s economy has been relied on public debt in order to enhance the economic growth. As such, an understanding  of the dynamics between public debt and economic growth is very important in addressing the obstacles to economic growth. The study investigates the impact of public debt on economic growth using data from 2000 to 2015. The study employs least squares method and regression model to capture the impact of public debt on economic growth. The results of the analysis indicate that there is a negative impact of total public debt, especially the external debt on economic growth. 

scholarly journals A Robust and Adaptive Complementary Kalman Filter Based on Mahalanobis Distance for Ultra Wideband/Inertial Measurement Unit Fusion Positioning

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3435 ◽  
Author(s):  
Xin Li ◽  
Yan Wang ◽  
Kourosh Khoshelham
Keyword(s):  
Kalman Filter ◽  
Mahalanobis Distance ◽  
Inertial Measurement Unit ◽  
Least Squares Method ◽  
Ultra Wideband ◽  
Measurement Unit ◽  
Observation Error ◽  
System State ◽  
Inertial Measurement ◽  
The Impact

Ultra wideband (UWB) has been a popular technology for indoor positioning due to its high accuracy. However, in many indoor application scenarios UWB measurements are influenced by outliers under non-line of sight (NLOS) conditions. To detect and eliminate outlying UWB observations, we propose a UWB/Inertial Measurement Unit (UWB/IMU) fusion filter based on a Complementary Kalman Filter to track the errors of position, velocity and direction. By using the least squares method, the positioning residual of the UWB observation is calculated, the robustness factor of the observation is determined, and an observation weight is dynamically set. When the robustness factor does not exceed a pre-defined threshold, the observed value is considered trusted, and adaptive filtering is used to track the system state, while the abnormity of system state, which might be caused by IMU data exceptions or unreasonable noise settings, is detected by using Mahalanobis distance from the observation to the prior distribution. When the robustness factor exceeds the threshold, the observed value is considered abnormal, and robust filtering is used, whereby the impact of UWB data exceptions on the positioning results is reduced by exploiting Mahalanobis distance. Experimental results show that the observation error can be effectively estimated, and the proposed algorithm can achieve an improved positioning accuracy when affected by outlying system states of different quantity as well as outlying observations of different proportion.

scholarly journals Does the Prevalence of Obesity Affect the Demand for Soft Drinks? Evidence from Cross-Country Panel Data

2022 ◽  
Vol 19 (2) ◽  
pp. 938
Author(s):  
Fabrizio Ferretti ◽  
Michele Mariani ◽  
Elena Sarti
Keyword(s):  
Nutrition Education ◽  
Least Squares Method ◽  
Soft Drink ◽  
Soft Drinks ◽  
Market Demand ◽  
Reverse Causality ◽  
Soft Drink Consumption ◽  
Variable Approach ◽  
Prevalence Of Obesity ◽  
The Impact

The impact of soft drinks on obesity has been widely investigated during the last decades. Conversely, the role of obesity as a factor influencing the demand for soft drinks remains largely unexplored. However, understanding potential changes in the demand for soft drinks, as a result of changes in the spread of obesity, may be useful to better design a comprehensive strategy to curb soft drink consumption. In this paper, we aim to answer the following research question: Does the prevalence of obesity affect the demand for soft drinks? For this purpose, we collected data in a sample of 97 countries worldwide for the period 2005–2019. To deal with problems of reverse causality, an instrumental variable approach and a two-stage least squares method were used to estimate the impact of the age-standardized obesity rate on the market demand for soft drinks. After controlling for several demographic and socio-economic confounding factors, we found that a one percent increase in the prevalence of obesity increases the consumption of soft drinks and carbonated soft drinks by about 2.37 and 1.11 L per person/year, respectively. Our findings corroborate the idea that the development of an obesogenic food environment is a self-sustaining process, in which obesity and unhealthy lifestyles reinforce each other, and further support the need for an integrated approach to curb soft drink consumption by combining sugar taxes with bans, regulations, and nutrition education programs.

scholarly journals Impact of the Ownership Structure on the Financial Performance of Banks: Comparative Study between Conventional and Islamic Banks

2019 ◽  
Vol 4 (2) ◽  
pp. 50-63
Author(s):  
Achraf Haddad ◽  
Anis El Ammari ◽  
Abdelfattah Bouri
Keyword(s):  
Financial Performance ◽  
Ownership Structure ◽  
Least Squares Method ◽  
Conflicts Of Interest ◽  
Positive Impact ◽  
Ordinary Least Squares ◽  
Performance Measure ◽  
Islamic Banks ◽  
Two Samples ◽  
The Impact

According to the literature of corporate governance, ownership structure is advanced as a non-dissociable mechanism of control intended to follow the stakeholders and especially used by shareholders to monitor the conflicts of interest and the opportunistic behavior of managers. Several previous studies have focused on the impact of ownership structure on financial performance separately in conventional or in Islamic banks. However, the comparative studies between these two impacts are non-existent. In this research, we compared the impacts of this governance mechanism on the financial performance in the two types of banks by using the Ordinary Least Squares method. Data relating to financial performance and ownership structure of banks come from 16 countries. Two samples were collected: the first one included 63 conventional banks, whereas the second one integrated 63 Islamic banks whose data are available over the period (2010-2018). Panel results showed that partial effect of each determinant of ownership structure on each measure of financial performance varied from one banks’ type to another and from one performance measure to another. Besides, the reconciliation of similar models revealed many differences between the same impacts’ signs. Therefore, we concluded that in both banks’ types the ownership structure has a positive impact on the financial performance. While, the negative part of the same impact is less significant in Islamic banks. JEL Classification:  F33, G20, G21, G24, G30.

scholarly journals MACROECONOMIC STABILITY AND SOCIAL PROGRESS IN THE EU MEMBER STATES AND UKRAINE

2018 ◽  
Vol 4 (1) ◽  
pp. 53-64 ◽  
Author(s):  
Oleksii Lyulyov
Keyword(s):  
Human Capital ◽  
Social Factors ◽  
Least Squares Method ◽  
Social Progress ◽  
Integral Index ◽  
Eu Member States ◽  
Human Capital Index ◽  
The Impact ◽  
The Eu ◽  
Macroeconomic Stability

The main purpose of the study is the role and influence of social factors on macroeconomic stability. The research is based on the hypothesis that countries with greater macroeconomic stability achieve greater social progress. The integrated index of human capital is proposed as a target for the construction of an appropriate system for monitoring social progress, and in the future – identifying the impact on macroeconomic stability. The main stages of estimating the integral index of human capital are: identification of relevant indicators that will form each of the sub-indices; filtering the selected indicators in the previous stage based on the analysis of the correlation matrix of each of the subindices; normalization of indicators in each of the subindices, calculation of the integral index for each of the subindices, calculation of the final integral index of human capital. The calculations of the integrated capital human capital index for some of the EU countries (Latvia, Lithuania, Poland, Croatia, Romania) and Ukraine for the period 2000–2015 allowed us to conclude that Romania and Ukraine were on a marginal level of social progress, while Lithuania, Poland and Croatia in the range of moderate level. The use of the OLS (the least squares) method to determine the significance of changes in social progress to macroeconomic stability has revealed a positive and statistically significant impact of social progress on macroeconomic stability.

scholarly journals Agriculture Sector Credit and Output Relationship in Nepal

2020 ◽  
pp. 33-53
Author(s):  
Arjun Kumar Dahal ◽  
Khagendra Kumar Thapa
Keyword(s):  
Commercial Banks ◽  
Agricultural Sector ◽  
Least Squares Method ◽  
Manufacturing Sector ◽  
Agriculture Sector ◽  
Industrial Sectors ◽  
Long Run ◽  
Integration Test ◽  
The Government ◽  
The Impact

Purpose: The purpose of this study is to find out the condition of priority of commercial banks to provide loans to the agricultural sector and to find the relationship and impact of agricultural loans to the agricultural GDP of Nepal. Objectives: This study aims to compare the condition of loan disbursements in agricultural and manufacturing sectors. It further aims to compare loan percent with growth and contribution to the GDP of the agricultural and industrial sectors and tries to show the impact of agricultural loans to the agricultural GDP of Nepal. Methods: It was based on a descriptive and analytical research design. Statistical tools standard deviation, correlation, regression, etc. are used and Excel, and EViews software are used for the statistical calculations. Statistical calculations and graphs are simultaneously used to show and compare the condition of variables. Results: Commercial banks give higher priority to the manufacturing sector for loans than the agricultural sector. The Johansen Co-integration test indicates no long-run relationship between loans of commercial banks and agricultural output in Nepal. However, the least-squares method, it indicates that a positive causal relationship between agricultural loans and agricultural growth. Implications: The loans of commercial banks directly stimulate the growth of agriculture but the amount of growth is less noticeable. Thus, it is concluded that the commercial bank's loan alone cannot affect and control the growth of the agricultural sector of the Nepalese economy therefore the government should increase its expenditure on the agricultural sector.

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