Rapid calculation method for estimating static and dynamic performances of closed hydrostatic guideways

2017 ◽  
Vol 69 (6) ◽  
pp. 1040-1048 ◽  
Author(s):  
Zhiwei Wang ◽  
Yi Liu ◽  
Feng Wang
Keyword(s):  
Dynamic Model ◽  
Lagrange Equation ◽  
Dynamic Stiffness ◽  
Step Response ◽  
Nonlinear Spring ◽  
Content Type ◽  
New Model ◽  
Linear Spring ◽  
Spring Coefficient ◽  
Better Than

Purpose The purpose of this paper is to establish a simplified model of the closed hydrostatic guideway for the rapid analysis of static and dynamic characteristics. Further, the influence of compressibility and dynamic frequency are taken into consideration in the new dynamic model. Design/methodology/approach The new model is based on the second kind of Lagrange equation. In this model, the closed hydrostatic guideway is supported by 12 pads, and each oil pad is equivalent to a nonlinear spring-damper system. The equivalent spring coefficient and damper coefficient of the oil pad are extracted by the three different equivalent methods. Finally, the validation experiments of step load response and dynamic stiffness are conducted on a hydrostatic guideway. Findings For solving the step response, the linear spring-damper model and the nonlinear spring-damper Model 1 are better than the nonlinear spring-damper Model 2. The accuracy of the three methods are very high for static stiffness calculation. For the calculation of dynamic stiffness, the nonlinear spring-damper Model 2 is better than the nonlinear spring-damper Model 1. The linear spring-damper model has low precision for dynamic stiffness calculation, especially at high frequency. The accuracy of the new model is validated by experiments. Originality/value The equivalent method of nonlinear spring-damper system has higher accuracy. Different equivalent methods should be adopted for different load types. The computational speeds of the new dynamic model with the three methods are much better than finite element method (about ten times).

New Model with Spring and Simulation of Flexible Manipulator

2014 ◽  
Vol 513-517 ◽  
pp. 3840-3843
Author(s):  
Ying Tian ◽  
Jian Hua Qian ◽  
Qing Song Liu ◽  
Jie Yuan
Keyword(s):  
Computer Simulation ◽  
Dynamic Model ◽  
Elastic Energy ◽  
Lagrange Equation ◽  
Rigid Bodies ◽  
Flexible Manipulator ◽  
Dynamic Parameters ◽  
New Model ◽  
Real Model ◽  
Model Computer

For easily calculated and more accurate dynamic model of single flexible manipulator, a new model was built through connection of spring and two rigid bodies. It is approximate to the real model of single manipulator in trajectory of end point. With simplifying manipulator and introducing simplified and Predetermined elastic energy of manipulator, Lagrange equation was used to built dynamic model based on the new model. And based on dynamic model, computer simulation result of dynamic parameters with Matlab software proved that the new model is available simple and easily-adjusted.

scholarly journals Dynamic Analysis and Experiment of 6-DOF Compliant Platform Based on Bridge-Type Amplifier

Micromachines ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1024
Author(s):  
Chao Lin ◽  
Shan Zheng ◽  
Mingdong Jiang
Keyword(s):  
Dynamic Model ◽  
Natural Frequency ◽  
Theoretical Calculations ◽  
Lagrange Equation ◽  
Damping Ratio ◽  
Elastic Beam ◽  
Analytical Models ◽  
Step Response ◽  
Element Analysis ◽  
Bridge Type

In this paper, we establish a dynamic model of a six-degrees-of-freedom (6-DOF) compliant positioning platform based on bridge-type amplifiers. Based on the elastic beam theory and energy relationship, we derived the bridge-type amplifier’s dynamic model using the Lagrange equation. Then, we established a dynamic model of the compliant platform based on the equivalent mass and equivalent stiffness of the bridge-type amplifier, and the analysis formula of the natural frequency was derived. Finally, the analytical models of natural frequencies of the bridge-type amplifier and the compliant platforms were verified using the finite element analysis (FEA) method. Through modal experiments, the damping ratio and natural frequency were identified. Step response experiments in the X/Y direction and Z direction were performed. The phenomenon that the experimental results appeared to match the theoretical calculations indicates that the dynamic model was accurate.

scholarly journals Ambidexterity and organizational learning: revisiting and reconnecting the literatures

2019 ◽  
Vol 26 (4) ◽  
pp. 337-351 ◽  
Author(s):  
Jacob Brix
Keyword(s):  
Organizational Learning ◽  
Absorptive Capacity ◽  
Empirical Data ◽  
Design Methodology ◽  
Organizational Ambidexterity ◽  
Exploration And Exploitation ◽  
Seminal Paper ◽  
Content Type ◽  
New Model ◽  
Multiple Levels

PurposeThe purpose of the study is to investigate how the processes of exploration and exploitation have developed in parallel in the literature of organizational ambidexterity and organizational learning, since James March published his seminal paper in 1991. The goal of the paper is to provide a synthesis of exploration and exploitation based on the two areas of literature.Design/methodology/approachThe study is conceptual and no empirical data have been used.FindingsThe study advances current understanding of exploration and exploitation by building a new model for organizational ambidexterity that takes into account multiple levels of learning, perspectives from absorptive capacity and inter-organizational learning.Originality/valueThe study’s novelty lies in the creation and discussion of a synthesis of exploration and exploitation stemming from organizational ambidexterity and organizational learning.

Nature-inspired hybrid deep learning for race detection by face shape features

2020 ◽  
Vol 13 (3) ◽  
pp. 365-388
Author(s):  
Asha Sukumaran ◽  
Thomas Brindha
Keyword(s):  
Feature Extraction ◽  
Hybrid Algorithm ◽  
Shape Features ◽  
Error Performance ◽  
Color Feature ◽  
Content Type ◽  
Dragonfly Algorithm ◽  
Face Shape ◽  
Race Detection ◽  
Better Than

PurposeThe humans are gifted with the potential of recognizing others by their uniqueness, in addition with more other demographic characteristics such as ethnicity (or race), gender and age, respectively. Over the decades, a vast count of researchers had undergone in the field of psychological, biological and cognitive sciences to explore how the human brain characterizes, perceives and memorizes faces. Moreover, certain computational advancements have been developed to accomplish several insights into this issue.Design/methodology/approachThis paper intends to propose a new race detection model using face shape features. The proposed model includes two key phases, namely. (a) feature extraction (b) detection. The feature extraction is the initial stage, where the face color and shape based features get mined. Specifically, maximally stable extremal regions (MSER) and speeded-up robust transform (SURF) are extracted under shape features and dense color feature are extracted as color feature. Since, the extracted features are huge in dimensions; they are alleviated under principle component analysis (PCA) approach, which is the strongest model for solving “curse of dimensionality”. Then, the dimensional reduced features are subjected to deep belief neural network (DBN), where the race gets detected. Further, to make the proposed framework more effective with respect to prediction, the weight of DBN is fine tuned with a new hybrid algorithm referred as lion mutated and updated dragon algorithm (LMUDA), which is the conceptual hybridization of lion algorithm (LA) and dragonfly algorithm (DA).FindingsThe performance of proposed work is compared over other state-of-the-art models in terms of accuracy and error performance. Moreover, LMUDA attains high accuracy at 100th iteration with 90% of training, which is 11.1, 8.8, 5.5 and 3.3% better than the performance when learning percentage (LP) = 50%, 60%, 70%, and 80%, respectively. More particularly, the performance of proposed DBN + LMUDA is 22.2, 12.5 and 33.3% better than the traditional classifiers DCNN, DBN and LDA, respectively.Originality/valueThis paper achieves the objective detecting the human races from the faces. Particularly, MSER feature and SURF features are extracted under shape features and dense color feature are extracted as color feature. As a novelty, to make the race detection more accurate, the weight of DBN is fine tuned with a new hybrid algorithm referred as LMUDA, which is the conceptual hybridization of LA and DA, respectively.

scholarly journals An Improved Image Denoising Model Based on Nonlocal Means Filter

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yan Jin ◽  
Wenyu Jiang ◽  
Jianlong Shao ◽  
Jin Lu
Keyword(s):  
Image Denoising ◽  
Natural Images ◽  
Nonlocal Means ◽  
New Model ◽  
Model Based ◽  
Better Than

The nonlocal means filter plays an important role in image denoising. We propose in this paper an image denoising model which is a suitable improvement of the nonlocal means filter. We compare this model with the nonlocal means filter, both theoretically and experimentally. Experiment results show that this new model provides good results for image denoising. Particularly, it is better than the nonlocal means filter when we consider the denoising for natural images with high textures.

Current CITE-ings from the popular and trade computing press: telework and telecommuting

2016 ◽  
Vol 33 (1) ◽  
pp. 21-22 ◽  
Author(s):  
Martin Kesselman
Keyword(s):  
Literature Review ◽  
Design Methodology ◽  
Virtual Reference ◽  
Content Type ◽  
Advantages And Disadvantages ◽  
Better Than

Purpose – This article examines Current CITE-ings from the Popular and Trade Computing Press, Telework and Telecommuting Design/methodology/approach – The methodology adopted is a literature review. Findings – Readily available technologies now allow librarians to perform most of their work-offsite. Some traditional building-based services such as reference, have been taken over by virtual reference and now even instruction offers options on par with or even better than classroombased questions such as a webinar that can be viewed and reviewed at any time or by having librarians embedded into various courseware packages. Researchlimitations/implications – Librarians no longer need be limited to a single library; groups of subject librarians can work together in the cloud to provide services to multiple universities. Originality/value – This article collates some articles from the non-library literature that mayprovide some ideas and review advantages and disadvantages for both the library and employee

Synthetic individual binaural audio delivery by pinna image processing

2014 ◽  
Vol 10 (3) ◽  
pp. 239-254 ◽  
Author(s):  
Simone Spagnol ◽  
Michele Geronazzo ◽  
Davide Rocchesso ◽  
Federico Avanzini
Keyword(s):  
Sound Source ◽  
Low Complexity ◽  
Head Orientation ◽  
Sound Sources ◽  
Content Type ◽  
Localization Test ◽  
Subjective Measurements ◽  
Head Related Transfer Function ◽  
Practical Implications ◽  
Better Than

Purpose – The purpose of this paper is to present a system for customized binaural audio delivery based on the extraction of relevant features from a 2-D representation of the listener’s pinna. Design/methodology/approach – The most significant pinna contours are extracted by means of multi-flash imaging, and they provide values for the parameters of a structural head-related transfer function (HRTF) model. The HRTF model spatializes a given sound file according to the listener’s head orientation, tracked by sensor-equipped headphones, with respect to the virtual sound source. Findings – A preliminary localization test shows that the model is able to statically render the elevation of a virtual sound source better than non-individual HRTFs. Research limitations/implications – Results encourage a deeper analysis of the psychoacoustic impact that the individualized HRTF model has on perceived elevation of virtual sound sources. Practical implications – The model has low complexity and is suitable for implementation on mobile devices. The resulting hardware/software package will hopefully allow an easy and low-tech fruition of custom spatial audio to any user. Originality/value – The authors show that custom binaural audio can be successfully deployed without the need of cumbersome subjective measurements.

Comparison of the effects of the food supplementation programmes of ICDS centers and primary schools at Bali Gram Panchayat, Arambagh, West Bengal, India

2014 ◽  
Vol 34 (3/4) ◽  
pp. 232-246
Author(s):  
Gopal Chandra Mandal ◽  
Kaushik Bose ◽  
Slawomir Koziel
Keyword(s):  
Nutritional Status ◽  
Primary Schools ◽  
West Bengal ◽  
Food Supplementation ◽  
Content Type ◽  
Active Involvement ◽  
Quality Of Food ◽  
The Government ◽  
Better Than

Purpose – Developing countries like India, accounts for about 40 percent of undernourished children in the World and it is largely due to the result of dietary inadequacy in relation to their needs. The purpose of this paper was to evaluate the changes in the nutritional status of the children, from their preschool days to the present primary school days. Design/methodology/approach – The present investigation was conducted at 20 Integrated Child Development Service (ICDS) centers (Center-A) and 15 primary schools (Center-B) in Bali Gram Panchayat, Arambag, Hooghly District of West Bengal, India, at an interval of three to four years. A total of 1,012 children (boys=498; girls=514) aged two to six years old enrolled in these ICDS centers and a total of 603 children (boys=300, girls=303), aged five to ten years were studied from the 15 primary schools who were the beneficiaries of ICDS centers. Underweight (weight-for-age Z-score (WAZ)) and wasting (weight-for height Z-score (WHZ)) were used to assess the nutritional status. Findings – The nutritional situation (both in case of underweight and wasting) was better in Center B as compared with Center A. In general, the nutritional condition of boys was better than girls. Center had a very significant effect on both WAZ as well as WHZ, irrespective of age and sex. Sex has a significant impact only on WAZ. Interestingly, there was no significant sex-center interaction for both WAZ as well as WHZ. The children of the area were getting Mid Day Meal supplied through the school authorities which was comparatively better than the ICDS centers’ food supplementation. Better monitoring of nutritional supplementation at primary schools may be an important factor. Practical implications – In ICDS centers, only the Anganwari worker is responsible in running and implementing the programs offered by the Government. However, at primary schools, the active involvement of all the teachers to run the program may have effectively led to have better results. Furthermore, the Government's focus should not be only on the increase the area covered by the ICDS program, but focus should be to increase the quality of food supplied, proper monitoring of the implementation and increase the allocation of funds. Appropriate measures may be taken by the authorities regarding this. Originality/value – The results of the study will help in policy making in reducing the prevalence of undernutrition.

Effect of female executives on Chinese cultural media enterprise efficiency

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ying Li ◽  
Yung-Ho Chiu ◽  
Tai-Yu Lin ◽  
Hongyi Cen
Keyword(s):  
Boards Of Directors ◽  
Company Performance ◽  
Tobit Regression ◽  
Female Executives ◽  
Two Stage ◽  
Content Type ◽  
Female Directors ◽  
The Impact ◽  
Cultural Media ◽  
Better Than

Purpose As more women are now being appointed to senior and top management positions and invited to sit on boards of directors, they are now directly participating in strategic company decision-making. As female directors have been found to provide new ideas, increase company competitiveness, efficiency and performance and bring a greater number of external resources to a company than male directors, this paper aims to put female directors as a variable into the data envelopment analysis (DEA) and statistical models to explore the effect of female directors on operating performances. The DEA first quantified and measured the company efficiencies, after which the statistical model analyzed the correlations between the variables to specifically identify the impact of female decision makers on the operating efficiencies in state-owned and private enterprises. Design/methodology/approach A novel two-stage, meta-hybrid dynamic DEA was developed to explore Chinese cultural media company efficiencies under optimal input and output resource allocations, after which Tobit Regression was applied to determine the effect of female executives on these efficiencies. Findings From 2012 to 2016, the overall efficiencies in Chinese state-owned cultural media enterprises were better than in the private cultural media enterprises. The overall technology gaps (TGs) in the state-owned cultural media enterprises were better than in the private cultural media enterprises. Originality/value Previous research has tended to focus on the causal relationships between female senior executives and business performances; however, there have been few studies on the relationships between female executives and company performance from an efficiency perspective (optimal resource allocation). This paper, therefore, is the first to develop a novel two-stage, meta-hybrid dynamic DEA to examine Chinese cultural media enterprise efficiencies, and the first to apply Tobit Regression to assess the effect of female executives on those efficiencies.

Computational predictions for predicting the performance of steel 1 panel shear wall under explosive loads

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Aydin Shishegaran ◽  
Behnam Karami ◽  
Elham Safari Danalou ◽  
Hesam Varaee ◽  
Timon Rabczuk
Keyword(s):  
Steel Plate ◽  
Plate Thickness ◽  
Ensemble Model ◽  
Maximum Deflection ◽  
Explosive Load ◽  
Statistical Parameters ◽  
Content Type ◽  
A Value ◽  
Error Terms ◽  
Better Than

Purpose The resistance of steel plate shear walls (SPSW) under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the conventional weapons effect program (CONWEP) model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a multiple linear regression (MLR), multiple Ln equation regression (MLnER), gene expression programming (GEP), adaptive network-based fuzzy inference (ANFIS) and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads. Design/methodology/approach The SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads. Findings The resistance of SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads. Originality/value The resistance of SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads.

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