scholarly journals The Gauss pendulum

2021 ◽  
Vol 5 ◽  
pp. 3
Author(s):  
Julio Carlos Teixeira ◽  
Pâmella Gonçalves Martins ◽  
Amanda Schwartzmann ◽  
Jeroen Schoenmaker
Keyword(s):  
Model Simulation ◽  
Energy State ◽  
Final Height ◽  
Simulated Data ◽  
Free Software ◽  
Potential Well ◽  
Laboratory Equipment ◽  
Well Model ◽  
The Difference ◽  
Remarkable Agreement

Recently, the Gauss rifle has gained attention as an interesting problem for physics and engineering education. In this manuscript we propose and analyze a novel problem that, while being related to the Gauss rifle, is rather simpler: the Gauss pendulum, which yields more consistent results and allows further agreement between model, simulation and experimental data. The Gauss pendulum, unlike the rifle, does not involve rotational movement of balls and the difference between the initial and final energy state of the system can be easily accessed by measuring the final height of the swinging projected ball. An extensive assessment of a Gauss pendulum has been developed using free software and accessible laboratory equipment. Focusing on the validation of the magnetic potential well model to understand the gain in kinetic energy, it was possible to obtain a remarkable agreement between the experimental and theoretically simulated data.

Fault Diagnostics Using Genetic Algorithm for Advanced Cycle Gas Turbine

2002 ◽  
Author(s):  
Suresh Sampath ◽  
Ankush Gulati ◽  
Riti Singh
Keyword(s):  
Objective Function ◽  
Gas Turbine ◽  
Model Simulation ◽  
Engine Performance ◽  
Simulated Data ◽  
Performance Model ◽  
Simple Cycle ◽  
Fault Diagnostics ◽  
Model Based ◽  
The Difference

This paper describes a new approach to the development of a fault diagnostics and prognostic capability for an advanced cycle gas turbine. It is based on techniques using sensor based and model based information. Sensor based information is the actual information obtained from the real engine and the model based information comes from the data obtained from engine performance model simulation with a permutation of implanted faults taking into account sensor noise and bias. The approach adopted here is to minimize an objective function which represents the difference between the actual and simulated data and the minimized objective function allows us identify the nature of fault. After the initial success with simple cycle engines, it was decided to extend this technique to advanced cycle engines. The technique is being tested on an in-house model of an intercooled recuperated engine with variable geometry similar to the ICR-WR21cycle. A detailed analysis of the technique applied to simple cycle and advanced cycle will be presented.

scholarly journals Linear Growth and Final Height after Treatment for Cushing’s Disease in Childhood

2000 ◽  
Vol 85 (9) ◽  
pp. 3262-3265
Author(s):  
Marie-Christine Lebrethon ◽  
Ashley B. Grossman ◽  
Farhad Afshar ◽  
P. Nicholas Plowman ◽  
G. Michael Besser ◽  
...  
Keyword(s):  
Cushing’S Disease ◽  
Final Height ◽  
Growth Failure ◽  
Height Velocity ◽  
Cushing's Disease ◽  
Childhood And Adolescence ◽  
Target Height ◽  
Gnrh Analog ◽  
The Mean ◽  
The Difference

Abstract Cushing’s disease is associated with growth failure in childhood and adolescence. Growth and final height were analyzed in 10 patients who were cured or in remission after treatment of Cushing’s disease. Seven males and 3 females, aged 6.8–17.6 yr (bone age, 3.3- 15.4 yr), had transsphenoidal surgery, which was combined with pituitary irradiation (4500 cGy in 25 fractions) in 5 patients. At presentation, 5 patients were prepubertal (males), and 5 were pubertal (2 males and 3 females). The mean height sd score was −2.15 ± 1.26 (range, −0.21 to −4.32) compared with mean target height sd score of −0.43 ± 0.58. Height velocity in 6 patients was subnormal (0.9–3.8 cm/yr). After treatment, short-term height velocity, over a mean interval of 0.57 yr, in 8 patients not receiving human GH (hGH) therapy, was variable (range, 0.8–7.6 cm/yr). GH stimulation tests (insulin tolerance test/glucagon) in 9 subjects showed peak GH levels of 0.5–20.9 mU/L. Eight were treated with hGH (14 IU/m2·wk), combined in 2 girls and 1 boy with a GnRH analog. After 1 yr of hGH, the mean height sd score had increased from −2.45 ± 1.0 at initiation of hGH to −2.07± 1.2 (P = 0.01). GH therapy was continued until final height or latest assessment. The mean final height sd score (n = 6) was −1.24 ± 1.38, and at the latest assessment the mean height sd score (n = 4) was− 1.52 ± 1.33. Combining these 2 groups, the mean height sd score was −1.36 ± 1.29. The difference between final or latest height sd score and target height sd score was 0.93 ± 1.13, i.e. less (P = 0.005) than the difference between height and target height sd score of 1.72 ± 1.26 at presentation. In conclusion, catch-up and favorable long-term growth was seen after treatment for Cushing’s disease. Posttreatment GH deficiency was frequent, and early hGH replacement may have contributed to the encouraging outcome.

Introduction to light absorption: visible and ultraviolet spectra

2000 ◽  
Author(s):  
Robert K. Poole ◽  
Uldis Kalnenieks
Keyword(s):  
Electromagnetic Radiation ◽  
Light Absorption ◽  
Energy State ◽  
Monochromatic Light ◽  
Heat Radiation ◽  
Infrared Light ◽  
Visible Radiation ◽  
Absorption Of Light ◽  
The Difference

Light is a form of electromagnetic radiation, usually a mixture of waves having different wavelengths. The wavelength of light, expressed by the symbol λ, is defined as the distance between two crests (or troughs) of a wave, measured in the direction of its progression. The unit used is the nanometre (nm, 10-9 m). Light that the human eye can sense is called visible light. Each colour that we perceive corresponds to a certain wavelength band in the 400-700 nm region. Spectrophotometry in its biochemical applications is generally concerned with the ultraviolet (UV, 185-400 nm), visible (400-700 nm) and infrared (700-15 000 nm) regions of the electromagnetic radiation spectrum, the former two being most common in laboratory practice. The wavelength of light is inversely related to its energy (E), according to the equation: . . . E = ch/ λ . . . where c denotes the speed of light, and h is Planck’s constant. UV radiation, therefore, has greater energy than the visible, and visible radiation has greater energy than the infrared. Light of certain wavelengths can be selectively absorbed by a substance according to its molecular structure. Absorption of light energy occurs when the incident photon carries energy equal to the difference in energy between two allowed states of the valency electrons, the photon promoting the transition of an electron from the lower to the higher energy state. Thus biochemical spectrophotometry may be referred to as electronic absorption spectroscopy. The excited electrons afterwards lose energy by the process of heat radiation, and return to the initial ground state. An absorption spectrum is obtained by successively changing the wavelength of monochromatic light falling on the substance, and recording the change of light absorption. Spectra are presented by plotting the wavelengths (generally nm or μm) on the abscissa and the degree of absorption (transmittance or absorbance) on the ordinate. For more information on the theory of light absorption, see Brown (1) and Chapters 2, 3 and 4. The most widespread use of UV and visible spectroscopy in biochemistry is in the quantitative determination of absorbing species (chromophores), known as spectrophotometry.

scholarly journals A Novel Type of Stochastic Resonance Potential Well Model and Its Application

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 160191-160202 ◽  
Author(s):  
Shangbin Jiao ◽  
Shuang Lei ◽  
Wei Jiang ◽  
Qing Zhang ◽  
Weichao Huang
Keyword(s):  
Stochastic Resonance ◽  
Potential Well ◽  
Well Model

A Force Control Joint for Robot–Environment Contact Application

2019 ◽  
Vol 11 (3) ◽  
Author(s):  
Qilong Wang ◽  
Wei Wang ◽  
Xilun Ding ◽  
Chao Yun
Keyword(s):  
Force Control ◽  
Model Simulation ◽  
Industrial Robot ◽  
Artificial Muscle ◽  
Hysteresis Model ◽  
Link Length ◽  
Nonlinear Hysteresis ◽  
The Difference ◽  
Parallel Configuration ◽  
Improved Accuracy

Accurate and robust force control is still a great challenge for robot–environment contact applications, such as in situ repair, polishing, and assembly. To tackle this problem, this paper proposes a force control joint with a parallel configuration, including two identical four-bar linkages driven by linear springs to push up the output end of the joint, and a parallel-connected pneumatic artificial muscle (PAM) to pull down its output end. In the new design, the link length of the linkages will be optimized to make the difference between the profile of the linkage and that of PAM constant within the limits of the joint given the force–displacement profile of PAM at a certain level of its input pressure. Furthermore, PAM's nonlinear hysteresis effect, which is believed to limit the accuracy of the joint's force control, will be represented by a new dynamics model that is to be developed from the classical Bouc–Wen (BW) hysteresis model. Simulation tests are then conducted to reveal that the adoption of the PAM hysteresis model yields improved accuracy of force control, and a series of curve trajectory tracking experiments are performed on a six-joint universal industrial robot to verify that the parallel force control joint is capable to enhance force control accuracy for robot contact applications.

Oxygen diffusion and mitochondrial respiration in neuroblastoma cells

1989 ◽  
Vol 256 (6) ◽  
pp. C1207-C1213 ◽  
Author(s):  
M. Robiolio ◽  
W. L. Rumsey ◽  
D. F. Wilson
Keyword(s):  
Respiratory Rate ◽  
Oxygen Pressure ◽  
Oxygen Diffusion ◽  
External Medium ◽  
Energy State ◽  
Neuroblastoma Cells ◽  
Metabolic Energy ◽  
Human Neuroblastoma ◽  
Coupled Cells ◽  
The Difference

Suspensions of human neuroblastoma cells consume oxygen at a constant rate when the oxygen pressure is greater than approximately 11 Torr. The rate of oxygen consumption, however, becomes dependent on the oxygen pressure below this level. The falling respiratory rate at the lower pressures gives rise to an oxygen pressure for half-maximal respiration (P50) of approximately 0.8 Torr, which is consistent with the 0.5 Torr value for suspensions of isolated mitochondria in the presence of ATP (J. Biol. Chem. 263: 2712-2718, 1988). When the cellular metabolic energy state is lowered by addition of an uncoupler of mitochondrial oxidative phosphorylation, the respiratory rate increases up to fivefold, but the P50 decreases to approximately 0.6 Torr. In the cells treated with uncoupler, the P50 decreases further when the mitochondrial respiratory rate is inhibited with amobarbital (amytal), an inhibitor of the respiratory chain. The additional decrease in P50 is proportional to the decrease in respiratory rate. Thus, for cells treated with uncoupler, the P50 appears to be limited by oxygen diffusion from the external medium to the mitochondria. When the respiratory rate of the uncoupled cells is inhibited to the level of coupled cells, the P50 for the former is less than 0.15 Torr. This indicates that for coupled cells the difference in oxygen pressure from the external medium to the mitochondria is less than 0.15 Torr at half-maximal respiratory rate and does not significantly affect the P50 for oxygen that occurs at 0.8 Torr.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Positron annihilation in simple condensed gases

1990 ◽  
Vol 68 (12) ◽  
pp. 1362-1376 ◽  
Author(s):  
A. T. Stewart ◽  
C. V. Briscoe ◽  
J. J. Steinbacher
Keyword(s):  
Positron Annihilation ◽  
Reasonable Agreement ◽  
Theoretical Calculations ◽  
Bubble Formation ◽  
The Self ◽  
Correlation Technique ◽  
Potential Well ◽  
Well Model ◽  
Adequate Data ◽  
Solid He

The angular-correlation technique of positron annihilation has been used to detect and measure the localized bubble state of positronium (Ps) in liquid Ne, Ar, Kr, H2, and N2 and in liquid and solid He at various pressures and temperatures. No bubble state was seen in liquid O2 or in solid Ne and Ar. The dynamics of bubble formation is not yet understood. In the cases where theoretical calculations, and adequate data, exist, viz. He, Ar, and H2, there is reasonable agreement for the momentum of the photons from the annihilation of positrons with the outer electrons of these atoms. The Ps annihilations from the self-trapped bubble state are reasonably well described in terms of a simple finite potential-well model.

Parameter-Induced Stochastic Resonance in Wireless Sensor Network Signal Processing

2010 ◽  
Vol 121-122 ◽  
pp. 646-650
Author(s):  
Zi Kai Zhao ◽  
Guo Hua Hui
Keyword(s):  
Signal Processing ◽  
Wireless Sensor Network ◽  
Sensor Network ◽  
Stochastic Resonance ◽  
Noise Intensity ◽  
System Parameter ◽  
Wireless Sensor ◽  
Potential Well ◽  
Processing Level ◽  
Well Model

Parameter-induced stochastic resonance (PSR) using double potential well model was focused in this paper. Based on the former stochastic resonance study, system parameter µ was used to explore the resonance characteristics. A bluetooth-based wireless sensor network (WSN) was adopted to obtain the experimental data for parameter-induced stochastic resonance simulating. Under fixed noise intensity range, the changes of system parameter µ led to a systematic output resonance. Simulating results demonstrated that the systematic parameter µ could lead to stochastic resonance at signal processing level.

Driver's Speed Decision-Making Model Based on ANFIS

2014 ◽  
Vol 488-489 ◽  
pp. 955-960 ◽  
Author(s):  
Lian Li ◽  
Song Yang ◽  
Wen Jing Cao
Keyword(s):  
Decision Making ◽  
Fuzzy Inference ◽  
Model Simulation ◽  
Original Data ◽  
Vehicle Speed ◽  
Anfis Model ◽  
Inference System ◽  
Microscopic Traffic Simulation ◽  
Car Following ◽  
The Difference

To simulate the driver's ability to deal with uncertainty and solve the unsmooth problem in the driving-status-transformation between free-traveling and car-following during the microscopic traffic simulation, the Adaptive Neuro-Fuzzy Inference System (ANFIS) was introduced to model the driver's speed decision-making behavior which integrated the free-traveling and car-following behavior. The difference between velocity and desired speed was added into the inputs of the ANFIS model besides vehicle speed, relative distance and relative velocity which commonly appeared in car-following models. In this paper, the NGSIM (Next Generation Simulation) data was used to calibrate and evaluate the model. With the analysis and pretreatment of NGSIM data, drivers reaction time was calibrated, drivers were clustered into three categories according to the level of recklessness, and the desired speed of different driver characteristic in different vehicle was approximated as the corresponding free speed. Using the processed NGSIM data, the ANFIS model was trained and the model output was validated and compared with the original data. The results showed that the ANFIS model performed well. In addition, the output of ANFIS model under car-following state was compared with that of GM model. This comparison provided a better chance to analyze the performance of the model and showed that the model simulation the driving data in a more realistic way.

DYNAMIC POTENTIAL WELL GENERATION AND CONTROL USING DOUBLE RESONATORS INCORPORATING AN ADD/DROP FILTER

2010 ◽  
Vol 24 (32) ◽  
pp. 3071-3080 ◽  
Author(s):  
B. PIYATAMRONG ◽  
K. KULSIRIRAT ◽  
W. TECHITDHEERA ◽  
S. MITATHA ◽  
P. P. YUPAPIN
Keyword(s):  
Optical Tweezers ◽  
Optical Filter ◽  
Design System ◽  
Potential Well ◽  
Pulse Control ◽  
Optical Signals ◽  
Dynamic Potential ◽  
Field Peak ◽  
The Difference ◽  
And Control

We propose a novel system of the dynamic potential well generation and control using light pulse control within an add/drop optical filter. The multiplexing signals of the dark solition with bright/Gaussian pulses are controlled, tuned and amplified within the system. The optical storage rings are embedded within the add/drop optical filter system, whereas the generated optical signals can be stored and amplified within the design system. In application, the storage signals can be configured to be an optical trapping tool which is known as optical tweezers, where the high field peak or well can be formed. The advantages are that the dynamic well can be stored and the array of well can be generated for multiple well applications. The difference in time of the first two dynamic wells of 1 ns is noted.

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