Transit-time limited frequency response of InGaAs MSM photodetectors

1990 ◽  
Vol 37 (11) ◽  
pp. 2285-2291 ◽  
Author(s):  
J.B.D. Soole ◽  
H. Schumacher
Keyword(s):  
Frequency Response ◽  
Transit Time ◽  
Limited Frequency ◽  
Msm Photodetectors

Nonlinear filter properties of the thick ascending limb

1997 ◽  
Vol 273 (4) ◽  
pp. F625-F634 ◽  
Author(s):  
H. E. Layton ◽  
E. Bruce Pitman ◽  
Leon C. Moore
Keyword(s):  
Steady State ◽  
Frequency Response ◽  
Transit Time ◽  
Concentration Profile ◽  
Tubuloglomerular Feedback ◽  
Thick Ascending Limb ◽  
Transport Parameters ◽  
Nodal Structure ◽  
Nacl Concentration ◽  
Fluid Transit Time

A mathematical model was used to investigate the filter properties of the thick ascending limb (TAL), that is, the response of TAL luminal NaCl concentration to oscillations in tubular fluid flow. For the special case of no transtubular NaCl backleak and for spatially homogeneous transport parameters, the model predicts that NaCl concentration in intratubular fluid at each location along the TAL depends only on the fluid transit time up the TAL to that location. This exact mathematical result has four important consequences: 1) when a sinusoidal component is added to steady-state TAL flow, the NaCl concentration at the macula densa (MD) undergoes oscillations that are bounded by a range interval envelope with magnitude that decreases as a function of oscillatory frequency; 2) the frequency response within the range envelope exhibits nodes at those frequencies where the oscillatory flow has a transit time to the MD that equals the steady-state fluid transit time (this nodal structure arises from the establishment of standing waves in luminal concentration, relative to the steady-state concentration profile, along the length of the TAL); 3) for any dynamically changing but positive TAL flow rate, the luminal TAL NaCl concentration profile along the TAL decreases monotonically as a function of TAL length; and 4) sinusoidal oscillations in TAL flow, except at nodal frequencies, result in nonsinusoidal oscillations in NaCl concentration at the MD. Numerical calculations that include NaCl backleak exhibit solutions with these same four properties. For parameters in the physiological range, the first few nodes in the frequency response curve are separated by antinodes of significant amplitude, and the nodes arise at frequencies well below the frequency of respiration in rat. Therefore, the nodal structure and nonsinusoidal oscillations should be detectable in experiments, and they may influence the dynamic behavior of the tubuloglomerular feedback system.

scholarly journals Overvoltages and Transients Identification In On-line Bushing Monitoring

2020 ◽  
Vol 69 (3) ◽  
Author(s):  
Wieslaw Gil ◽  
Wiktor Masłowski ◽  
Przemysław Wronek
Keyword(s):  
Frequency Response ◽  
Support Service ◽  
Monitoring Systems ◽  
Resonance Phenomena ◽  
Limited Frequency ◽  
On Line ◽  
High Dynamics

Overvoltages and transients are sometimes recognized as the cause of bushings’ rapid failure. This fact is confirmed by the studies published at the 2018 CIGRE session. They can also initiate dangerous resonance phenomena in transformer windings. The identification of very fast overvoltages characterized by high dynamics of voltage changes, so-called "transients", is difficult due to the limited frequency response of station voltage transformers. However, the bushing monitoring systems, based on the so-called "voltage method" can be used for this purpose successfully. There are several running bushing monitoring systems based on this method in Poland. The transients’ events are registered together with their oscillographs in Transformer Monitoring Systems (TMS). The overvoltage statistics are also performed to support service procedures.The TMS are integrated with station systems, which greatly increases the possibility of overvoltages phenomena analyzing.

Reduction of hole transit time in GaAs MSM photodetectors by p-type /spl delta/-doping

1996 ◽  
Vol 8 (11) ◽  
pp. 1525-1527 ◽  
Author(s):  
Jen-Inn Chyi ◽  
Yi-Jiunn Chien ◽  
Rong-Heng Yuang ◽  
Jia-Lin Shieh ◽  
Jen-Wei Pan ◽  
...  
Keyword(s):  
Transit Time ◽  
Delta Doping ◽  
P Type ◽  
Msm Photodetectors
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