NUMERICAL AND EXPERIMENTAL STUDY OF REGULAR AND CHAOTIC MOTION OF TRIPLE PHYSICAL PENDULUM

2008 ◽  
Vol 18 (10) ◽  
pp. 2883-2915 ◽  
Author(s):  
JAN AWREJCEWICZ ◽  
BOGDAN SUPEŁ ◽  
CLAUDE-HENRI LAMARQUE ◽  
GRZEGORZ KUDRA ◽  
GRZEGORZ WASILEWSKI ◽  
...  
Keyword(s):  
Real System ◽  
Physical Parameters ◽  
Real Plane ◽  
Friction Modeling ◽  
Rolling Bearings ◽  
Novel Approach ◽  
Direct Measurements ◽  
Triple Pendulum ◽  
Characteristic Features ◽  
Regular And Chaotic Motion

Nonlinear dynamics of a real plane and periodically forced triple pendulum is investigated experimentally and numerically. Mathematical modeling includes details, taking into account some characteristic features (for example, real characteristics of joints built by the use of roller bearings) as well as some imperfections (asymmetry of the forcing) of the real system. Parameters of the model are obtained by a combination of the estimation from experimental data and direct measurements of the system's geometric and physical parameters. A few versions of the model of resistance in the joints are tested in the identification process. Good agreement between both numerical simulation results and experimental measurements have been obtained and presented. Some novel features of our real system chaotic dynamics have also been reported, and a novel approach of the rolling bearings friction modeling is proposed, among other.

scholarly journals A Denoising Autoencoder-Based Bearing Fault Diagnosis System for Time-Domain Vibration Signals

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Yi Gu ◽  
Jiawei Cao ◽  
Xin Song ◽  
Jian Yao
Keyword(s):  
Fault Diagnosis ◽  
Time Domain ◽  
Rolling Bearing ◽  
Rolling Bearings ◽  
Bp Network ◽  
Bearing Fault ◽  
Bearing Fault Diagnosis ◽  
Novel Approach ◽  
Fault Diagnosis System ◽  
Original Time

The condition monitoring of rotating machinery is always a focus of intelligent fault diagnosis. In view of the traditional methods’ excessive dependence on prior knowledge to manually extract features, their limited capacity to learn complex nonlinear relations in fault signals and the mixing of the collected signals with environmental noise in the course of the work of rotating machines, this article proposes a novel approach for detecting the bearing fault, which is based on deep learning. To effectively detect, locate, and identify faults in rolling bearings, a stacked noise reduction autoencoder is utilized for abstracting characteristic from the original vibration of signals, and then, the characteristic is provided as input for backpropagation (BP) network classifier. The results output by this classifier represent different fault categories. Experimental results obtained on rolling bearing datasets show that this method can be used to effectively diagnose bearing faults based on original time-domain signals.

Intraoperative optical imaging of metabolic changes after direct cortical stimulation – a clinical tool for guidance during tumor resection?

2018 ◽  
Vol 63 (5) ◽  
pp. 587-594
Author(s):  
Martin Oelschlägel ◽  
Tobias Meyer ◽  
Gabriele Schackert ◽  
Matthias Kirsch ◽  
Stephan B. Sobottka ◽  
...  
Keyword(s):  
Optical Imaging ◽  
Brain Tissue ◽  
Tumor Tissue ◽  
Tumor Resection ◽  
Cortical Stimulation ◽  
Normal Brain ◽  
Clinical Tool ◽  
Novel Approach ◽  
Intact Brain ◽  
Characteristic Features

AbstractBrain tumor resection is even today one of the most challenging disciplines in neurosurgery. The current state of the art for the identification of tumor tissue during the surgical procedure comprises a wide variety of different tools, each with its own limitations and drawbacks. In this paper, we present a novel approach, the use of optical imaging in connection with direct electrical cortical stimulation (DCS), for identification of impaired tumor tissue and functional intact normal brain tissue under intraoperative conditions. Measurements with an optical imaging setup were performed as a proof of concept on three patients who underwent tumor resection of superficial gliomas. Direct electrical stimulations were applied on tumor tissue and surrounding brain tissue in each patient and characteristic features from the observed changes in the optical properties were compared between the different groups. The results reveal that in all patients a differentiation between non-functional tumor tissue and functional intact brain tissue was possible, and the technique might be a useful clinical tool in the future.

scholarly journals Self-organization of cortical areas in the development and evolution of neocortex

2020 ◽  
Vol 117 (46) ◽  
pp. 29212-29220 ◽  
Author(s):  
Nabil Imam ◽  
Barbara L. Finlay
Keyword(s):  
Activity Patterns ◽  
Basic Mechanism ◽  
Physical Parameters ◽  
Network Growth ◽  
Cortical Areas ◽  
Mirror Reversal ◽  
Correlated Activity ◽  
The Matrix ◽  
Characteristic Features ◽  
Development And Evolution

While the mechanisms generating the topographic organization of primary sensory areas in the neocortex are well studied, what generates secondary cortical areas is virtually unknown. Using physical parameters representing primary and secondary visual areas as they vary from monkey to mouse, we derived a network growth model to explore if characteristic features of secondary areas could be produced from correlated activity patterns arising from V1 alone. We found that V1 seeded variable numbers of secondary areas based on activity-driven wiring and wiring-density limits within the cortical surface. These secondary areas exhibited the typical mirror-reversal of map topography on cortical area boundaries and progressive reduction of the area and spatial resolution of each new map on the caudorostral axis. Activity-based map formation may be the basic mechanism that establishes the matrix of topographically organized cortical areas available for later computational specialization.

scholarly journals Application of Plackett Burman and Box Behnken Design for the Optimization of a-glucosidase Production by Thermophillic Thermomyces dupontii

2020 ◽  
Vol 71 (9) ◽  
pp. 32-38
Author(s):  
Kinza Nisar ◽  
Roheena Abdullah ◽  
Afshan Kaleem ◽  
Mehwish Iqtedar ◽  
Faiza Saleem ◽  
...  
Keyword(s):  
Ammonium Sulphate ◽  
Industrial Applications ◽  
Inoculum Size ◽  
Quadratic Model ◽  
Physical Parameters ◽  
Potential Candidate ◽  
Sulphate Concentration ◽  
Novel Approach ◽  
Burman Design ◽  
Thermomyces Dupontii

A consecutive optimization based on statistical approach was applied for a-glucosidase production by both wild and mutant T. dupontii. Plackett Burman design (PBD) with two levels was employed in order to screen the significant effect of different nutritional and physical parameters through submerged fermentation. Among all nine variables tested in PBD, incubation time, inoculum size and ammonium sulphate concentration were selected. The Box-Behnken approach was further applied for process optimization. The a-glucosidase production for both wild and mutant T.dupontii was obtained at 72 h of incubation, 1.25 mL inoculum size and 0.25% ammonium sulphate concentration with relatively 95% correlation between the experimentally predicted and observed values. The duration of maximum enzyme production in RSM was cost-saving and fast. The quadratic model was in satisfactory adjustment with the experimental data with high R2 value which describes 98.90% of response variability of the model. Moreover, the novel approach of this present work is that, consecutive optimization were applied for maximum a-glucosidase production using response surface methodology by both wild and mutant thermophillic T. dupontii. Results revealed that thermophillic mutant T. dupontii could be potential candidate for industrial applications.

Fault Diagnosis of Rolling Bearings Using Data Mining Techniques and Boosting

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Muhammet Unal ◽  
Yusuf Sahin ◽  
Mustafa Onat ◽  
Mustafa Demetgul ◽  
Haluk Kucuk
Keyword(s):  
Fault Diagnosis ◽  
High Performance ◽  
Acoustic Analysis ◽  
Real Life ◽  
Roc Curves ◽  
Support Vector ◽  
Loading Conditions ◽  
Rolling Bearings ◽  
Novel Approach ◽  
Classification Tasks

Rolling bearings are key components in most mechanical facilities; hence, the diagnosis of their faults is very important in predictive maintenance. Up to date, vibration analysis has been widely used for fault diagnosis in practice. However, acoustic analysis is still a novel approach. In this study, acoustic analysis with classification is used for fault diagnosis of rolling bearings. First, Hilbert transform (HT) and power spectral density (PSD) are used to extract features from the original sound signal. Then, decision tree algorithm C5.0, support vector machines (SVMs) and the ensemble method boosting are used to build models to classify the instances for three different classification tasks. Performances of the classifiers are compared w.r.t. accuracy and receiver operating characteristic (ROC) curves. Although C5.0 and SVM show comparable performances, C5.0 with boosting classifier indicates the highest performance and perfectly discriminates normal instances from the faulty ones in each task. The defect sizes to create faults used in this study are notably small compared to previous studies. Moreover, fault diagnosis is done for rolling bearings operating at different loading conditions and speeds. Furthermore, one of the classification tasks incorporates diagnosis of five states including four different faults. Thus, these models, due to their high performance in classifying multiple defect scenarios having different loading conditions and speeds, can be readily implemented and applied to real-life situations to detect and classify even incipient faults of rolling bearings of any rotating machinery.

scholarly journals STUDI KELAYAKAN TAMBAK UNTUK BUDIDAYA RUMPUT LAUT (Gracilaria sp) DI DESA PANYIWI KECAMATAN CENRANA KABUPATEN BONE

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Muh Riski Amir
Keyword(s):  
Dissolved Oxygen ◽  
Sampling Method ◽  
Water Source ◽  
Observation Point ◽  
Physical Parameters ◽  
Substrate Type ◽  
Tidal Amplitude ◽  
Weighting Method ◽  
Direct Measurements ◽  
Phosphate Nitrate

ABSTRACT                This research is a survey research that aims to determine the characteristics and level of feasibility of ponds for seaweed cultivation (Gracilaria sp) based on physical parameters (temperature, salinity, depth, brightness, phosphate, type of substrate, tidal amplitude and protection) and chemistry (pH, dissolved oxygen, Nitrate). The population in this study was the existing pond area in Panyiwi Village, Cenrana Subdistrict, Bone Regency, the sample as many as 8 points / observation station was determined using purposive sampling method based on the location and water source of the pond. Data collection time is done twice, morning and evening. Research data obtained by observation, direct measurements in the field (temperature, salinity, depth, brightness, dissolved oxygen, pH and protection) and laboratory analysis (phosphate, nitrate, and substrate type) were then analyzed using the weighting method. After obtaining the score value of each parameter at each observation point, then the assessment is feasible (S1) with a range of 68-87, quite feasible (S2) with a range of 48-67, and not feasible (N) with a range of 27- 47. So that obtained the results of each station in the morning, stations I, II, III, IV, V, VI, VII, VIII entered in quite decent categories (S2) and each station in the afternoon namely stations I, II, III, V , VI, VII, VIII also included in the category of quite feasible (S2) except on station IV it was in the category of not feasible (N) dry ponds due to low tide. 

Deterministic and Stochastic Prediction of the Hydrodynamics of a Three-Dimensional Body Falling Through Water

2008 ◽  
Author(s):  
Xuemei Zhu ◽  
Yuming Liu
Keyword(s):  
Deterministic Model ◽  
Three Dimensional ◽  
Field Measurements ◽  
The Body ◽  
Statistical Prediction ◽  
Viscous Drag ◽  
Physical Parameters ◽  
Practical Applications ◽  
Characteristic Features ◽  
Six Degree Of Freedom

We investigate the dynamics of a three-dimensional mine-shaped body falling through water deterministically and stochastically. A physics-based deterministic model, MINE6D, is developed for the prediction of the six degree-of-freedom motion of the body falling freely through water. In MINE6D, the hydrodynamic load due to the added inertia effect is obtained exactly by using a boundary-element method while the viscous drag associated with flow separation and vortex shedding is modeled using a quasi-steady approach. Since the mine motion is found to be highly sensitive to varying the physical parameters such as body geometry, mass distribution, and initial releasing conditions, we develop a stochastic model using Monte-Carlo MINE6D simulation for the statistical analysis of mine motions in practical applications. The statistical prediction is compared with available field measurements both qualitatively and quantitatively. The characteristic features and dependence on physical parameters of the statistical prediction of mine motions are investigated. The present study is of importance to the prediction of mine burial in seabed and the design of mines.

scholarly journals Expanding the framework of the varieties of capitalism: Turkey as a hierarchical market economy

2018 ◽  
Vol 9 (1) ◽  
pp. 42-51 ◽  
Author(s):  
Jiyan Kıran
Keyword(s):  
Market Economy ◽  
Latin American ◽  
Industrial Relations ◽  
Varieties Of Capitalism ◽  
Qualitative Comparison ◽  
Market Economies ◽  
Novel Approach ◽  
The Family ◽  
Characteristic Features ◽  
Core Features

This article both extends the debate on the varieties of capitalism theory beyond the existing literature to solve the ambiguous position of the variety of capitalism that is found in Turkey and brings a novel approach to the studies of the political economy of Turkey by adopting a firm-centred position using the varieties of capitalism framework. Based on a qualitative comparison with the dependent market economies (DMEs), mixed market economies (MMEs) and hierarchical market economies (HMEs), this article claims that Turkey is a hierarchical market economy with four characteristic features that are also found in Latin American economies. These core features are the dominance of the family-owned diversified business groups, state-regimented and weak industrial relations, low skills and the influence of MNCs.

A novel approach for incipient defect detection in rolling bearings using acoustic emission technique

2015 ◽  
Vol 89 ◽  
pp. 88-100 ◽  
Author(s):  
Juan Luis Ferrando Chacon ◽  
Vassilios Kappatos ◽  
Wamadeva Balachandran ◽  
Tat-Hean Gan
Keyword(s):  
Acoustic Emission ◽  
Defect Detection ◽  
Acoustic Emission Technique ◽  
Rolling Bearings ◽  
Novel Approach
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