scholarly journals THE COMPARISON OF THE DYNAMIC TESTS RESULTS FROM SENSORY PLATFORMS

2021 ◽  
Vol 7 (4) ◽  
pp. 131-134
Author(s):  
Monika Michalíková ◽  
Lucia Bednarčíková ◽  
Richard Staško ◽  
Jozef Živčák
Keyword(s):  
Diagnostic Method ◽  
Dynamic Test ◽  
Average Pressure ◽  
Dynamic Tests ◽  
Dynamic Output ◽  
Dynamic Analyses ◽  
The Right

The article deals with dynamic plantography, which is a popular diagnostic method focused on assessment of the foot condition during walking and to expose foot disorders. The aim of the paper is to discover whether it’s possible to do dynamic analyses on short platforms by using comparison of short and long sensory platform output. To get dynamic output were used ImportaMedica platforms, specific long platform Elegance and short platform Speed. Three subjects were involved in dynamic test on both platforms. The evaluated parameters were surface of the foot, maximum and average pressure, speed and gait line. By comparing these parameters the biggest difference was discovered in adapting walking because of the correct tread on short platform. When comparing the outputs from the long and short platforms, a longer duration of the right and left footsteps was recorded for all three subjects on the short platform.

scholarly journals Assessment of the Relationship between Y-Balance Test and Stabilometric Parameters in Youth Footballers

2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Damian Sikora ◽  
Małgorzata Pałac ◽  
Andrzej Myśliwiec ◽  
Tomasz Wolny ◽  
Paweł Linek
Keyword(s):  
Path Length ◽  
Dynamic Balance ◽  
Dynamic Test ◽  
Lower Limbs ◽  
Test Results ◽  
Dynamic Tests ◽  
Balance Test ◽  
Time Required ◽  
The Right ◽  
The Relationship

Objectives. The purpose of the study was to evaluate the correlation between dynamic test results obtained on a stabilometric platform and the results achieved on the Y-balance test (Y-BT). Method. The study group consisted of 52 adolescent athletes, aged 14 to 17 years. Each participant was evaluated in the scope of their ability to maintain dynamic balance using the Y-BT as well as via dynamic tests on the ‘Alfa’ stabilometric platform. The following parameters were analysed: (a) from the Y-BT—relative reach of the right and left lower limbs in the anterior, posterolateral, and posteromedial directions, as well as the side-to side difference in relative reach for each direction and (b) from the ‘Alfa’ platform—path length and time to reach the target using right and left lower limbs in the anterior and posterior directions. Results. A correlation between the results obtained on the stabilometric platform and the Y-BT was found only for the posteromedial direction. Statistical analysis demonstrated that the increased difference between the right and left lower limbs in the posteromedial test is related to an increase in time taken to reach the points located forward and to the left, and backwards and to the right, as well as an increase in the overall time required to complete the task on the stabilometric platform. Conclusions. The results from the Y-BT and stabilometric platform are weakly related in adolescents. These findings indicate that the Y-BT and stabilometric platform analyse different kinds of dynamic balance in adolescents. Thus, these tools should not be used interchangeably in clinical practice or scientific research.

The Invisible Evil Twin of an Adrenal Adenoma

2019 ◽  
Vol 4 (1) ◽  
pp. 58
Author(s):  
Aimi Fadilah Mohamad ◽  
Fatimah Zaherah Mohamed Shah ◽  
Nur Aisyah Zainordin ◽  
Ur 'Aini Eddy Warman ◽  
Nazimah Ab Mumin ◽  
...  
Keyword(s):  
Adrenal Glands ◽  
Adrenal Adenoma ◽  
Definitive Diagnosis ◽  
Dynamic Tests ◽  
Venous Sampling ◽  
Aldosterone Secretion ◽  
Aldosterone Level ◽  
Suppression Test ◽  
The Right ◽  
Secondary Causes

Primary aldosteronism (PA) causes a persistently elevated blood pressure (BP) due to excessive release of the hormone aldosterone from the adrenal glands. Classically, it is called Conn’s syndrome and is described as the triad of hypertension and hypokalemia with the presence of unilateral adrenal adenoma. It can be cured with surgical resection of the aldosterone-secreting adenoma leading to resolution of hypertension, hypokalemia and increased cardiovascular risk associated with hyperaldosteronism. We present a case of a man with previous ischemic heart disease (IHD) who presented with resistant hypertension. Investigations for secondary causes of hypertension revealed an elevated aldosterone level and saline suppression test confirmed the diagnosis of PA. Radiological examination revealed a left adrenal adenoma and a normal right adrenal gland. However, adrenal venous sampling showed lateralization of aldosterone secretion towards the right. He subsequently underwent a laparoscopic right adrenalectomy which improved his BP control promptly. This case highlights the importance of recognizing the need to investigate for secondary causes of hypertension. It also underscores the importance of dynamic tests, which may not be easily accessible to most clinicians but should pursue, to allow a definitive diagnosis and effective treatment.

Inspection and Model Experiment of a Damaged Arch Bridge

2007 ◽  
Vol 340-341 ◽  
pp. 223-228
Author(s):  
Ying Fang Fan ◽  
Zhi Qiang Hu ◽  
Jing Zhou
Keyword(s):  
Model Experiment ◽  
Dynamic Test ◽  
Dynamic Responses ◽  
Dynamic Tests ◽  
Arch Bridge ◽  
Mechanical Responses ◽  
Organic Glasses ◽  
Bridge Model ◽  
Static And Dynamic Tests ◽  
Good Agreement

The structural behavior of an old six-span reinforced concrete arch bridge, which has been in service for about 40 years, is investigated. Field monitoring (inclusive of test of material property, static and dynamic test of the bridge) was conducted, static and dynamic responses of the bridge are obtained. Based on the primitive bridge, a scaled one-span bridge model was fabricated by organic-glasses. Both the static and dynamic tests were executed on the bridge model in the laboratory. Since the arch rib is the crucial member for the arch bridge, 7 notches were cut on both arch ribs of the bridge model to simulate different damages of the arch rib. Mechanical responses of the bridge with different damages on the arch ribs were achieved. FEM analyses were preformed on the bridge as well. Numerical results show good agreement with the experimental results.

scholarly journals Viscoelastic Parameters of Asphalt Mixtures Identified in Static and Dynamic Tests

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2084 ◽  
Author(s):  
Piotr Mackiewicz ◽  
Antoni Szydło
Keyword(s):  
Permanent Deformation ◽  
Asphalt Mixture ◽  
Dynamic Test ◽  
Asphalt Mixtures ◽  
Rheological Parameters ◽  
Dynamic Tests ◽  
Static Test ◽  
Viscoelastic Parameters ◽  
Static Creep ◽  
Asphalt Content

We present two methods used in the identification of viscoelastic parameters of asphalt mixtures used in pavements. The static creep test and the dynamic test, with a frequency of 10 Hz, were carried out based on the four-point bending beam (4BP). In the method identifying viscoelastic parameters for the Brugers’ model, we included the course of a creeping curve (for static creep) and fatigue hysteresis (for dynamic test). It was shown that these parameters depend significantly on the load time, method used, and temperature and asphalt content. A similar variation of parameters depending on temperature was found for the two tests, but different absolute values were obtained. Additionally, the share of viscous deformations in relation to total deformations is presented, on the basis of back calculations and finite element methods. We obtained a significant contribution of viscous deformations (about 93% for the static test and 25% for the dynamic test) for the temperature 25 °C. The received rheological parameters from both methods appeared to be sensitive to a change in asphalt content, which means that these methods can be used to design an optimal asphalt mixture composition—e.g., due to the permanent deformation of pavement. We also found that the parameters should be determined using the creep curve for the static analyses with persistent load, whereas in the case of the dynamic studies, the hysteresis is more appropriate. The 4BP static creep and dynamic tests are sufficient methods for determining the rheological parameters for materials designed for flexible pavements. In the 4BP dynamic test, we determined relationships between damping and viscosity coefficients, showing material variability depending on the test temperature.

Damage Identification for Masonry Materials Based on Bayesian Inference

2013 ◽  
Vol 405-408 ◽  
pp. 2498-2502
Author(s):  
Xiang Ping Fu ◽  
Bin Peng ◽  
Zheng Ji
Keyword(s):  
Monte Carlo ◽  
Markov Chain ◽  
Sampling Method ◽  
Damage Identification ◽  
Dynamic Test ◽  
Finite Element Models ◽  
Masonry Structures ◽  
Dynamic Tests ◽  
Bayesian Inferences ◽  
Mcmc Sampling

The basic frequency of masonry specimens can be obtained by dynamic tests with ambient or artificial excitation. The elastic modulus of masonry structures, as well as the damage factors, can then be determined by training their finite element models and make the calculated frequencies agree with the measured ones. Using 530 groups of dynamic test data, the damage factors of four masonry specimens were identified. The Bayesian inferences of the highly diverse measured results were conducted through a Markov Chain Monte Carlo (MCMC) sampling method, and the location of the damage was identified. The methodology was applicable, and can be used in the damage identification for other materials or structures.

Operation Modal Analysis of Pedestrian Bridge in Kroměříž

2020 ◽  
Vol 309 ◽  
pp. 281-287
Author(s):  
Kristína Bezručová ◽  
Radim Nečas ◽  
Jan Koláček
Keyword(s):  
Experimental Determination ◽  
Modal Analysis ◽  
Dynamic Test ◽  
Calculation Model ◽  
Mode Shapes ◽  
Modal Parameters ◽  
Dynamic Tests ◽  
Pedestrian Bridge ◽  
Before And After

The publication outlines the issue of the experimental determination of modal parameters of structures using a method called operational modal analysis. The principle of the method and possible approaches of calculation of modal parameters are presented. An example of the method’s application is the determination of mode shapes and frequencies of the repaired footbridge in Kroměříž where the dynamic test was performed twice – before and after reinforcement of the structure. The results of both dynamic tests and their comparisons with the results of the calculation model performed in the ANSYS environment are presented in this article. Additionally, and integral to this article is a description of the completed footbridge reconstruction.

Modal Analysis and Dynamic Test of Steel Slag Vehicle

2013 ◽  
Vol 397-400 ◽  
pp. 564-567 ◽  
Author(s):  
Kun Li Mao
Keyword(s):  
Modal Analysis ◽  
Test Procedure ◽  
Steel Slag ◽  
Dynamic Test ◽  
Dynamic Tests ◽  
Iron And Steel ◽  
Finite Element Software ◽  
Data Process ◽  
Field Dynamic ◽  
Design And Manufacture

Steel slag vehicles with tilting arm are advanced equipment used in iron and steel factory for short distance delivery. With great impact force and severe vibration when pouring steel slag, strength of equipment structure must be enough. In product design, theoretical study and simulation of steel slag vehicles were completed using commercial finite element software and dynamics software. Static strength and dynamic tests of some steel slag vehicle were finished using dynamic and static stain instruments, acceleration transducer in order to verify the computer analysis result. The modal analysis result of steel slag vehicle, the field dynamic test procedure and data process are shown in this article. In the end of paper, conclusions are drawn useful for design and manufacture of heavy-duty equipment such as steel slag vehicles.

Non-Linearity in Dynamic Tests. I. Vibration Test Methods

1961 ◽  
Vol 34 (2) ◽  
pp. 527-554
Author(s):  
V. E. Gough
Keyword(s):  
Phase Plane ◽  
Dynamic Test ◽  
Test Methods ◽  
Wave Form ◽  
Actual Behavior ◽  
Dynamic Tests ◽  
Important Conclusion ◽  
Single Degree Of Freedom ◽  
Phase Plane Method ◽  
Physical Quantities

Abstract In those cases where dynamic tests are to be interpreted in terms of the molecular structure of rubber, there is a definite need for a method of analysis which is wholly free from mathematical assumptions. Such a method of analysis is possible by the use of phase planes of velocity plotted against displacement. This is so because the slope of the trajectory at any point of the motion of any single degree of freedom system can be written solely in terms of physical quantities, namely, driving force, viscoelastic reaction and momentum. The analysis involves no hidden mathematical assumption. Methods of deriving stress strain relationships from phase plane trajectories are described. This phase plane method is discussed in some detail. Examples are given showing the inadequacy of the usual linear analysis in the case of rubberlike materials. Analysis shows that dynamic test machines should either apply a known motion and record a force-deflection curve or apply a force of known wave form and record the resulting motion as a phase plane trajectory. If force and motion are not kept independent of each other in this manner there is an inbuilt mathematical relationship which, more often than not, influences and falsifies the results. An important conclusion is that only when the nature of the non-linearities, or what is the same thing, the character of the functions which correctly describe the actual behavior of a vibrating system have been established by sound analysis of test data, should the phenomena be ascribed to the physical properties of the material. Because of the important consequence of the acceptance of some common mathematical steps in any analysis, certain of these are critically examined and their relevance discussed.

A robotic chewing simulator supplying six-axis mandibular motion, high occlusal force, and a saliva environment for denture tests

2021 ◽  
pp. 095441192110056
Author(s):  
Wenlong Qin ◽  
Ming Cong ◽  
Dong Liu ◽  
Xiang Ren
Keyword(s):  
Flow Rate ◽  
Failure Modes ◽  
Testing Machine ◽  
Dynamic Test ◽  
Dynamic Tests ◽  
Occlusal Force ◽  
Static Tests ◽  
Static Test ◽  
Axis Parallel

Six-axis motion is essential for the evaluation of the wear failure modes of dental prostheses with complete teeth morphologies, and a high occlusal force capacity is vital for static clenching and dynamic bruxism. Additionally, the saliva environment influences abrasive particles and crack growth. The present research was aimed at the development of a six-axis masticatory and saliva simulator with these capacities. The masticatory simulator was designed based on a six-axis parallel mechanism, and the saliva simulator consisted of a saliva circuit and a temperature control loop. A control system of the masticatory and saliva simulators was constructed. The operating interface includes a centric occlusal position search, a static test, a dynamic test, a saliva supply, and data reporting. The motion and force performances of the masticatory simulator were evaluated. The flow rate and temperature change of the saliva simulator were calculated. For the occlusal position-searching, the driving amplitude is linear with the moving variables during minor one-axis motion. For the static tests, the force capacity of the driving chain is 3540 N, while for the dynamic tests, the force capacity is 1390 N. The flow rate of the saliva is 0.18–51.84 mL/min, and the saliva can effectively wet the prosthesis without the risk of overflow. Moreover, the saliva temperature can increase from room temperature (23°C) to body temperature (37°C) in about 6 min. The proposed DUT-2 simulator with six-axis motion, high force, and a salvia environment provides an in vitro testing approach to validate numerical simulation results and explain the clinical failure modes of prostheses. The centric occlusal position-searching, static tests, and dynamic tests could therefore be executed using a single testing machine. Moreover, the proposed device is more compact than previously reported six-axis masticatory simulators, including the Bristol simulator and DUT-1 simulator.

scholarly journals Creep rupture of wallaby tail tendons.

1995 ◽  
Vol 198 (3) ◽  
pp. 831-845 ◽  
Author(s):  
X T Wang ◽  
R F Ker
Keyword(s):  
Dynamic Test ◽  
Primary Creep ◽  
Creep Rupture ◽  
Tertiary Creep ◽  
Dynamic Tests ◽  
Specimen Length ◽  
Creep Theory ◽  
Time To Rupture ◽  
Tail Tendon ◽  
Strength And Stiffness

The tail tendons from wallabies (Macropus rufogriseus) suffer creep rupture at stresses of 10 MPa or above, whereas their yield stress in a dynamic test is about 144 MPa. At stresses between 20 and 80 MPa, the time-to-rupture decreases exponentially with stress, but at 10 MPa, the lifetime is well above this exponential. For comparison, the stress on a wallaby tail tendon, when its muscle contracts isometrically, is about 13.5 MPa. Creep lifetime depends sharply on temperature and on specimen length, in contrast to strength and stiffness as observed in dynamic tests. The creep curve (strain versus time) can be considered as a combination of primary creep (decelerating strain) and tertiary creep (accelerating strain). Primary creep is non-damaging, but tertiary creep is accompanied by accumulating damage, with loss of stiffness and strength. 'Damage' is quantitatively defined as the fractional loss of stiffness. A creep theory is developed in which the whole of tertiary creep and, in particular, the creep lifetime are predicted from measurements made at the onset of creep, when the tendon is undamaged. This theory is based on a 'damage hypothesis', which can be stated as: damaged material no longer contributes to stiffness and strength, whereas intact material makes its full contribution to both.

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