Minimum-Time Constant Acceleration Orbit Transfer with First-Order Oblateness Effect

2000 ◽  
Vol 23 (4) ◽  
pp. 595-603 ◽  
Author(s):  
Jean Albert Kechichian
Keyword(s):  
Time Constant ◽  
Minimum Time ◽  
Constant Acceleration ◽  
Orbit Transfer ◽  
First Order ◽  
Oblateness Effect

Breath-by-breath VCO2 and VO2 required compensation for transport delay and dynamic response

1982 ◽  
Vol 52 (1) ◽  
pp. 79-84 ◽  
Author(s):  
H. Noguchi ◽  
Y. Ogushi ◽  
I. Yoshiya ◽  
N. Itakura ◽  
H. Yamabayashi
Keyword(s):  
Computer Simulation ◽  
Dynamic Response ◽  
Mass Spectrometer ◽  
Time Constant ◽  
Collection Method ◽  
Transport Delay ◽  
First Order ◽  
On Line

Both transport delay (DELAY) and dynamic response (RESPONSE) of a mass spectrometer would theoretically result in considerable errors in the breath-by-breath calculation of VCO2 and VO2. However, curiously, the contribution of RESPONSE has been ignored. The purpose of this study is to quantify the error caused by RESPONSE. We found that RESPONSE of a mass spectrometer was regarded as a first-order response. We determined DELAY and time constant (T) of RESPONSE and compensated the on-line calculation for both DELAY and RESPONSE and for DELAY only. With T of 150 and 100 ms, deviations of VCO2 from the gas-collection method were 8 +/- 6 and 8 +/- 6 ml/min with compensation for both DELAY and RESPONSE, and 69 +/- 10 and 50 +/- 5 ml/min with compensation for DELAY only, respectively (mean +/- SD). Similar results were obtained with VO2. A computer simulation of error caused by RESPONSE disclosed that the error linearly increased with increasing T. We conclude that to be accurate within +/- 5% of the exact value, compensation should be made when T exceeds 25 ms.

Step Response Characteristics of Anisotropic Gel Actuator Hybridized with Nanosheet Liquid Crystal

2019 ◽  
Vol 31 (5) ◽  
pp. 647-656 ◽  
Author(s):  
Hitoshi Kino ◽  
◽  
Akihiro Kiyota ◽  
Takumi Inadomi ◽  
Tomonori Kato ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Steady State ◽  
Time Constant ◽  
Step Response ◽  
Response Property ◽  
First Order ◽  
Response Characteristics ◽  
Thermal Change ◽  
Heating And Cooling ◽  
Original Size

In this study, we focus on a soft anisotropic gel actuator hybridized with nanosheet liquid crystal. This gel actuator is highly hydrophilic and can be operated underwater. Gel actuators can contract when heated and expand back to their original size when cooled down. It is anisotropic in the contraction direction, aligned with the orientation of the nanosheet liquid crystal. However, details of this step response property against the actuator undergoing thermal change have not been clarified. In this paper, we introduce a method to measure the step response using a square test sheet with a side length of 2–10 mm and thickness of 0.1–1.0 mm. This measurement was used to measure the heating and cooling step response. The obtained result was approximated using a first-order lag system to determine a steady-state value and time constant. In addition, the characteristics of steady-state value and time constant were clarified from the viewpoint of shapes such as specific surface area and thickness.

Binary search for time-constant estimation in first order systems, FiO2 - SpO2 case study

2013 ◽  
Author(s):  
Omid Sadeghi Fathabadi ◽  
Timothy J. Gale ◽  
Jan C. Olivier ◽  
Peter A. Dargaville ◽  
Kevin I. Wheeler ◽  
...  
Keyword(s):  
Time Constant ◽  
Binary Search ◽  
First Order

scholarly journals The kinetics of inactivation of the rod phototransduction cascade with constant Ca2+i.

1996 ◽  
Vol 107 (1) ◽  
pp. 19-34 ◽  
Author(s):  
A Lyubarsky ◽  
S Nikonov ◽  
E N Pugh
Keyword(s):  
G Protein ◽  
Time Constant ◽  
Inactivation Kinetics ◽  
First Order ◽  
Successful Model ◽  
Ringer’S Solution ◽  
Rhodopsin Kinase ◽  
Solution Bathing ◽  
Kinetics Of ◽  
Phototransduction Cascade

A rich variety of mechanisms govern the inactivation of the rod phototransduction cascade. These include rhodopsin phosphorylation and subsequent binding of arrestin; modulation of rhodopsin kinase by S-modulin (recoverin); regulation of G-protein and phosphodiesterase inactivation by GTPase-activating factors; and modulation of guanylyl cyclase by a high-affinity Ca(2+)-binding protein. The dependence of several of the inactivation mechanisms on Ca2+i makes it difficult to assess the contributions of these mechanisms to the recovery kinetics in situ, where Ca2+i is dynamically modulated during the photoresponse. We recorded the circulating currents of salamander rods, the inner segments of which are held in suction electrodes in Ringer's solution. We characterized the response kinetics to flashes under two conditions: when the outer segments are in Ringer's solution, and when they are in low-Ca2+ choline solutions, which we show clamp Ca2+i very near its resting level. At T = 20-22 degrees C, the recovery phases of responses to saturating flashes producing 10(2.5)-10(4.5) photoisomerizations under both conditions are characterized by a dominant time constant, tau c = 2.4 +/- 0.4 s, the value of which is not dependent on the solution bathing the outer segment and therefore not dependent on Ca2+i. We extended a successful model of activation by incorporating into it a first-order inactivation of R*, and a first-order, simultaneous inactivation of G-protein (G*) and phosphodiesterase (PDE*). We demonstrated that the inactivation kinetics of families of responses obtained with Ca2+i clamped to rest are well characterized by this model, having one of the two inactivation time constants (tau r* or tau PDE*) equal to tau c, and the other time constant equal to 0.4 +/- 0.06 s.

A Theoretical Analysis of Whirl Instability and Pneumatic Hammer for a Rigid Rotor in Pressurized Gas Journal Bearings

1967 ◽  
Vol 89 (2) ◽  
pp. 154-165 ◽  
Author(s):  
J. W. Lund
Keyword(s):  
Theoretical Analysis ◽  
Time Constant ◽  
Pressure Ratio ◽  
Journal Bearings ◽  
Restricted Feeding ◽  
Rigid Rotor ◽  
Eccentricity Ratio ◽  
Pneumatic Hammer ◽  
Small Eccentricity ◽  
First Order

A theoretical analysis is presented for the threshold of instability for a rigid rotor supported in hydrostatic gas journal bearings. Both rotationally induced instability (hybrid instability) and pneumatic hammer are considered. The analysis is based on a first-order perturbation with respect to the eccentricity ratio (i.e., the results are limited to small eccentricity ratios) and makes use of the linearized Ph-method [2, 5, 8]. The pressurized gas is supplied to the bearing through restricted feeding holes in the center plane of the bearing and the analysis takes into account the discreteness of the feeding holes, the feeder hole time constant, and inherent compensation effects. Numerical results are given in form of 16 graphs, showing the threshold of instability as a function of supply pressure ratio, feeding parameter and eccentricity ratio. Also, the effect of the feeder hole time constant is investigated with respect to pneumatic hammer.

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