scholarly journals Identification of Water Hammering for Centrifugal Pump Drive Systems

2020 ◽  
Vol 10 (8) ◽  
pp. 2683 ◽  
Author(s):  
Nabanita Dutta ◽  
Kaliannan Palanisamy ◽  
Umashankar Subramaniam ◽  
Sanjeevikumar Padmanaban ◽  
Jens Bo Holm-Nielsen ◽  
...  
Keyword(s):  
Linear Regression ◽  
Predictive Control ◽  
Wave Attenuation ◽  
Control Method ◽  
Early Stage ◽  
Linear Regression Analysis ◽  
Fast Fourier Transformation ◽  
Negative Wave ◽  
Pumping System ◽  
Drive Systems

Water hammering is a significant problem in pumping systems. It damages the pipelines of the pump drastically and needs to identify with an intelligent method. Various conventional methods such as the method of characteristics and wave attenuation methods are available to identify water hammering problems, and the predictive control method is one of the finest and time-saving methods that can identify the anomalies in the system at an early stage such that the device can be saved from total damage and reduce energy loss. In this research, a machine learning (ML) algorithm has used for a predictive control method for the identification of water hammering problems in a pumping system with the help of simulations and experimental-based works. A linear regression algorithm has been used in this work to predict water hammering problems. The efficiency of the algorithm is almost 90% compared to other ML algorithms. Through a Vib Sensor app-based device at different pressures and flow rates, the velocity of the pumping system, a fluctuation between healthy and faulty conditions, and acceleration value at different times have been collected for experimental analysis. A fault created to analyze a water hammering problem in a pumping system by the sudden closing and opening of the valve. When the valve suddenly closed, the kinetic energy in the system changed to elastic resilience, which created a series of positive and negative wave vibrations in the pipe. The present work concentrates on the water hammering problem of centrifugal pumping AC drive systems. The problem is mainly a pressure surge that occurs in the fluid, due to sudden or forced stops of valves or changes in the direction and momentum of the fluid. Various experimental results based on ML tool and fast Fourier transformation (FFT) analysis are obtained with a Vib Sensor testbed set-up to prove that linear regression analysis is the less time-consuming algorithm for fault detection, irrespective of data size.

Education, APOE ɛ4, and Cognition in Individuals with Subjective Cognitive Decline with Worry in the SILCODE Study

2021 ◽  
Vol 18 ◽  
Author(s):  
Guanqun Chen ◽  
Li Lin ◽  
Kun Yang ◽  
Ying Han
Keyword(s):  
Linear Regression ◽  
Cognitive Decline ◽  
Multiple Linear Regression ◽  
Early Stage ◽  
Linear Regression Analysis ◽  
Subjective Cognitive Decline ◽  
Linear Regression Models ◽  
Cognitive Domains ◽  
Apoe Ε4 ◽  
Positive Effect

Background: Education could offer a protective effect on cognition in individuals with Subjective Cognitive Decline (SCD), which is considered to be the early stage of Alzheimer’s Dis- ease (AD). However, the effect of education on cognition in SCD individuals with SCD-plus fea- tures is not clear. Objective: The aim of the study was to explore the effect of education on cognition in SCD individ- uals with SCD-plus features. Methods: A total of 234 individuals with SCD were included from the Sino Longitudinal Study on Cognitive Decline (SILCODE). Cognition was assessed across 4 domains (memory, executive, lan- guage, and general cognitive functions). Multiple linear regression models were constructed to ex- amine the effect of education on cognitive scores in individuals without worry (n=91) and with wor- ry (n=143). Furthermore, we assessed differences in effects between APOE ε4 noncarriers and APOE ε4 carriers in both groups. Results : Multiple linear regression analysis showed a positive effect of education on memory, ex- ecutive, and language cognition in individuals without worry and all cognitive domains in individu- als with worry. Furthermore, we found a positive effect of education on executive cognition in APOE ε4 noncarriers without worry and language and general cognition in APOE ε4 carriers with- out worry. Meanwhile, education had a positive effect on all cognitive domains in APOE ε4 noncar- riers with worry and executive, language, and general cognition in APOE ε4 carriers with worry. Conclusion: This study indicates that education has the potential to delay or reduce cognitive dec- line in SCD individuals with SCD-plus features.

Evaluation of Model Based Predictive Control Algorithms for Fractional Horse Power Drives

2015 ◽  
Vol 805 ◽  
pp. 231-240
Author(s):  
Matthias Blank ◽  
Sebastian Wendel ◽  
Philipp Loehdefink ◽  
Armin Dietz
Keyword(s):  
Cost Function ◽  
Predictive Control ◽  
Control Method ◽  
Dynamic Performance ◽  
Small Time ◽  
Control Algorithms ◽  
Model Based ◽  
Computational Requirement ◽  
Drive Systems ◽  
Horse Power

Model based predictive control is a new promising control method in the field of powerelectronics and electrical drives. The main advantages of MPC are simplicity and intuitiveness of thecontrol method. Constraints and nonlinearities of the system can easily be included, which makes thelinearisation of the system unnecessary. By using MPC it is possible to avoid the cascaded structureof common linear control methods and to gain a fast dynamic performance. A disadvantage is theneed to calculate the optimal actuating variable multiple times in every single sampling cycle leadsto a huge requirement of computational power. So far the computational requirement was the greatestbarrier for the practical application of model based predictive control in the field of power electronicsand electrical drive systems. In addition the small time constants of fractional horse power drivescomplicate the application of predictive control algorithms. In this paper, the feasibility of hardwareimplementation of a cost function based Finite Control Set MPC (FCS-MPC) algorithm for directspeed control of fractional horse power drives is explored. The cost function allows to address variouscontrol goals like dynamics of transitions and energy efficiency – an advantage linear conventionalcontrol methods cannot offer. Hitherto there are very few publications for direct predictive speed. Thepresented approach for direct predictive speed control includes a finite number of possible switchingstates of the converter. This considers the discrete nature of power converters and avoids the need formodulation. The basic principle of the control method is presented and the performance is demonstratedby simulations and experimental results for an industrial brushed type DC-motor.

scholarly journals Effect of enhanced recovery after surgery in the managements of ankle fracture patients: A single-center retrospective cohort study

2021 ◽  
Author(s):  
Yuefeng Yao ◽  
Guoqing Li ◽  
Su Liu ◽  
Ao Xiong ◽  
Chang Xu ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Multiple Linear Regression ◽  
Ankle Fracture ◽  
Enhanced Recovery ◽  
Enhanced Recovery After Surgery ◽  
Early Stage ◽  
Linear Regression Analysis ◽  
Univariate Analysis ◽  
Multiple Linear Regression Analysis

Abstract Background Ankle fracture is common and the treatment is embarrassed. Enhanced Recovery After Surgery (ERAS) has been successfully adopted for the improvement of efficacy and quality. However, application of ERAS in ankle fracture patients especially at the early stage is variable and remains to be clarified. We intent to explore the effect of ERAS among ankle fracture patients. Methods There were 29 male and 51 female patients aged 41.71 ± 14. 51 years who were consecutively grouped into non-ERAS group (n = 40) and ERAS group (n = 40). Univariate analysis and multiple linear regression analysis were applied to assess the association in outcomes and variables. Results AOFAS at post-operative 3 month (PO3M) and PO6M, costs, LOS, and pre-operative LOS were verified significantly in univariate analysis. Multiple linear regression analysis revealed that ERAS can improve AOFAS at PO3M (β = 7.06, 95% CI, 4.45–9.65) and PO6M (β = 5.08, 95% CI, 2.35–7.80), reduce costs (β = -6885.13, 95% CI, -12089.40 - -1680.85), and reduce LOS (β = -3.27, 95% CI, -4.97 - -1.57) among ankle fracture patients. With the numbers available, no significant differences were observed (p༞0.05) for the AOFAS at PO12M and PO24M, complications, or opioids consumption. Conclusion We found ERAS is superior to general protocol among proper ankle fracture patients, which can enhance rehabilitation and improve medical quality and efficiency especially at the early stage. ERAS protocol may have a promising future and worth promoting.

scholarly journals Effect of enhanced recovery after surgery in the managements of ankle fracture patients: a single-center retrospective cohort study

2020 ◽  
Author(s):  
Yuefeng Yao ◽  
Guoqing Li ◽  
Su Liu ◽  
Ao Xiong ◽  
Chang Xu ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Multiple Linear Regression ◽  
Ankle Fracture ◽  
Enhanced Recovery ◽  
Enhanced Recovery After Surgery ◽  
Early Stage ◽  
Linear Regression Analysis ◽  
Univariate Analysis ◽  
Multiple Linear Regression Analysis

Abstract Background Ankle fracture is common and the treatment is embarrassed. Enhanced Recovery After Surgery (ERAS) has been successfully adopted for the improvement of efficacy and quality. However, application of ERAS in ankle fracture patients especially at the early stage is variable and remains to be clarified. We intent to explore the effect of ERAS among ankle fracture patients. Methods There were 29 male and 51 female patients aged 41.71 ± 14. 51 years who were consecutively grouped into non-ERAS group (n = 40) and ERAS group (n = 40). Univariate analysis and multiple linear regression analysis were applied to assess the association in outcomes and variables. Results AOFAS at post-operative 3 month (PO3M) and post-operative 6 month (PO6M), costs, length of stay (LOS), and pre-operative LOS were verified significantly in univariate analysis. Multiple linear regression analysis revealed that ERAS can improve American Orthopaedic Foot and Ankle Society (AOFAS) at PO3M (β = 7.06, 95% CI, 4.45–9.65) and PO6M (β = 5.08, 95% CI, 2.35–7.80), reduce costs (β = -6885.13, 95% CI, -12089.40 - -1680.85) and LOS (β = -3.27, 95% CI, -4.97 - -1.57) among ankle fracture patients. With the numbers available, no significant differences were observed (p༞0.05) for the AOFAS at post-operative 12 month (PO12M) and post-operative 24 month (PO24M), complications, or opioids consumption. Conclusion We found ERAS is superior to general protocol among proper ankle fracture patients, which can enhance rehabilitation especially at the early stage and improve medical quality and efficiency by reducing costs and LOS. ERAS protocol may have a promising future and worth promoting.

PENGARUH FAKTOR-FAKTOR INTERNAL PERBANKAN TERHADAP NON PERFORMING FINANCING PADA BANK UMUM SYARIAH

2019 ◽  
Vol 6 (2) ◽  
pp. 115-130
Author(s):  
Eka Ambara Harci Putranta ◽  
Lilik Ambarwati
Keyword(s):  
Linear Regression ◽  
Multiple Linear Regression ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Capital Adequacy ◽  
Annual Reports ◽  
Regression Methods ◽  
Capital Adequacy Ratio ◽  
Negative Effect ◽  
Independent Variable

The study aims to analyze the influence of internal banking factors in the form of: Capital Adequency Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing at Sharia Banks. This research method used multiple linear regression analysis with the help of SPSS 16.00 software which is used to see the influence between the independent variables in the form of Capital Adequacy Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing. The sample of this study was 3 Islamic Commercial Banks, so there were 36 annual reports obtained through purposive sampling, then analyzed using multiple linear regression methods. The results showed that based on the F Test, the independent variable had an effect on the NPF, indicated by the F value of 17,016 and significance of 0,000, overall the independent variable was able to explain the effect of 69.60%. While based on the partial t test, showed that CAR has a significant negative effect, Total assets have a significant positive effect with a significance value below 0.05 (5%). Meanwhile FDR does not affect NPF.

ANALISIS PENGARUH INFLASI, KURS DAN IHSG TERHADAP RETURN REKSA DANA SAHAM PT NIKKO SECURITIES INDONESIA PERIODE 2014-2017

2019 ◽  
Vol 2 (2) ◽  
pp. 103
Author(s):  
Muhammad Rois Rois ◽  
Manarotul Fatati Fatati ◽  
Winda Ihda Magfiroh
Keyword(s):  
Regression Analysis ◽  
Exchange Rate ◽  
Linear Regression ◽  
Multiple Linear Regression ◽  
Stock Price ◽  
Price Index ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Equity Fund ◽  
Stock Price Index

This study aims to determine the effect of Inflation, Exchange Rate and Composite Stock Price Index (IHSG) to Return of PT Nikko Securities Indonesia Stock Fund period 2014-2017. The study used secondary data obtained through documentation in the form of PT Nikko Securities Indonesia Monthly Net Asset (NAB) report. Data analysis is used with quantitative analysis, multiple linear regression analysis using eviews 9. Population and sample in this research are PT Nikko Securities Indonesia. The result of multiple linear regression analysis was the coefficient of determination (R2) showed the result of 0.123819 or 12%. This means that the Inflation, Exchange Rate and Composite Stock Price Index (IHSG) variables can influence the return of PT Nikko Securities Indonesia's equity fund of 12% and 88% is influenced by other variables. Based on the result of the research, the variables of inflation and exchange rate have a negative and significant effect toward the return of PT Nikko Securities Indonesia's equity fund. While the variable of Composite Stock Price Index (IHSG) has a negative but not significant effect toward Return of Equity Fund of PT Nikko Securities Indonesia

Struktur Organisasi, Desain Kerja, Budaya Organisasi Dan Pengaruhnya Terhadap Produktivitas Karyawan Studi Kasus Pada PT. XX Di Jakarta

Liquidity ◽  
2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Yanti Budiasih
Keyword(s):  
Organizational Culture ◽  
Regression Analysis ◽  
Linear Regression ◽  
Organizational Structure ◽  
Research Method ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Job Design ◽  
Employee Productivity ◽  
Dominant Influence

The objectives of this study are to analyze changes in organizational structure, job design, organizational culture and its influence on employee productivity at PT. XX in Jakarta and to identify variables that have a dominant influence on the productivity of employees. The research method used is using multiple linear regression analysis. The results show that the all variables simultaneously and partially change the organizational structure, job design, and organizational culture has a significant impact on employee productivity at PT. XXin Jakarta.

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