In order to achieve the timing goals needed in their ASIC designs, many engineers decide to include phase-locked loops (PLLs). Phaselocked loops have a number of desirable properties that include the ability to multiply clock frequencies, correct clock duty cycles, and cancel out clock distribution delays. These properties allow designers to use inexpensive, low-frequency crystals as their off-...

A model of the RF feedback system for PEP-II has been developed to provide time-domain simulation and frequency-domain analysis of the complete system. The model includes the longitudinal beam dynamics, cavity fundamental resonance, feedback loops, and the nonlinear klystron operating near saturation. Transients from an ion clearing gap and a reference phase modulation from the longitudinal fee...

When discussing ultimate limits in ultrasensitive measurements, we have to take into account fundamental fluctuation processes as well as a realistic description of the measurement device. This requires to treat in the same theoretical framework a number of problems which are often tackled by different approaches. Real measurements always have a finite time resolution, that is also a characteri...

A formal proof is presented for a recently presented systolic array for recursive least squares estimation by inverse updates. The derivation of this systolic array is highly non-trivial due to the presence of data contra-flow and feedback loops in the underlying signal flow graph. This would normally prohibit pipelined processing. However, it is shown that suitable delays may be introduced int...

Safety and quality of travel on arterial networks tie closely to the performance of signalized intersections. Measures commonly used for intersection performance evaluations are control delay, queue length, and cycle failure. However, these variables are not directly available from typical configurations of traffic sensors designed for intersection signal control. Collecting vehicle control del...

This paper demonstrates a GPS receiver research platform. It can generate digital Immediate Frequency (IF) GPS signal and some signal synchronize functions on high dynamic and weak signal environment. It is based on a mathematical signal model which expresses the digitized IF GPS signal as a function of various errors during propagation. The simulator is able to simulate more than 12 GPS satell...

Translocation of the N-terminus of a type I signal anchor (SA-I) sequence across the endoplasmic reticulum membrane can be arrested by tagging with a streptavidin-binding peptide tag (SBP tag) and trapping by streptavidin. In the present study, we first examine the affinity required for the translocation arrest. When the SBP tag is serially truncated, the ability for arrest gradually decreases....

We investigate intensity variations and energy deposition in five coronal loops in active region cores. These were selected for their strong variability in the AIA/SDO 94 Å intensity channel. We isolate the hot Fe xviii and Fe xxi components of the 94 Å and 131 Å by modeling and subtracting the “warm” contributions to the emission. HMI/SDO data allow us to focus on “inter-moss” regions in the l...

Biochemical regulatory networks governing diverse cellular processes such as stress-response, differentiation and cell cycle often contain coupled feedback loops. We aim at understanding how features of feedback architecture, such as the number of loops, the sign of the loops and the type of their coupling, affect network dynamical performance. Specifically, we investigate how bistability range...