Air quality models compute the transformation of species in the atmosphere undergoing chemical and physical changes. The numerical algorithms used to predict these transformations should obey mass conservation and positive definiteness properties. Among all physical phenomena, the chemical kinetics solver provides the greatest challenge to attain these two properties. In general, most chemical ...

converge to a unique solution of the IVP up to the boundary of U [1]. In general, φn may converge slowly to the exact solution. The Picard iteration based integrator described in this paper has three main advantages. The the integrator has arbitrary order, is time adaptive, and has dense output. Dense output refers to the integrator being able to take time steps of variable length without havin...

Leapfrog integration has been the method of choice in N-body simulations owing to its low computational cost for a symplectic integrator with second order accuracy. We introduce a new leapfrog integrator that allows for variable timesteps for each particle in large N-body simulations. Tests with single particles in fixed potentials show that it behaves as a symplectic integrator. We then examin...

Continuous Stirred Tank Reactor (CSTR) has particular importance in chemical industry. CSTR has usually a nonlinear behavior which makes it difficult to control. The reactor has two parameters: the concentration and temperature of mixture both of which are uncertain. This case of CSTR has large disturbance in domain. In order for disturbance rejection, a controller has to be designed. In this p...

In this paper we formally describe the hybrid integrator-gain system (HIGS), which is a nonlinear integrator designed to avoid limitations typically associated with linear integrators. The HIGS keeps sign of its input and output equal, thereby inducing less phase lag than integrator, much like famous Clegg integrator. achieves reduced by projection controller dynamics instead using resets state...

The nucleus in eukaryotic cells is a highly organized and dynamic structure containing numerous subnuclear bodies. The morphological appearance of nuclear bodies seems to be a reflection of ongoing functions, such as DNA replication, transcription, repair, RNA processing and RNA transport. The integrator complex mediates processing of small nuclear RNA (snRNA), so it might play a role in nuclea...

The appropriate timing of flowering is crucial for the reproductive success of plants. Hence, intricate genetic networks integrate various environmental and endogenous cues such as temperature or hormonal statues. These signals integrate into a network of floral pathway integrator genes. At a quantitative level, it is currently unclear how the impact of genetic variation in signaling pathways o...

In this paper a very low-noise low-power correlated double sampled integrator has been presented. For attenuating the sampling thermal noise, two large capacitors are well incorporated in the integrator with no using large sampling and integrating capacitors that are necessary in ordinary integrators. The integrator is used in the front-end of a 24 bit, forth-order single-loop single-bit Delta-...

In this paper, we investigate the parameters affecting Total Harmonic Distortion (THD) and Power Supply Rejection Ratio (PSRR) in PWM Class D Amplifiers (CDAs) on the basis of linear models with feedback. From our mathematical analysis, we show that the THD of a PWM Class D amplifier with feedback can be improved by increasing the gain of the integrator through adding another amplifier at the o...

We present a receding horizon control scheme that utilizes a discrete time version of a nonlinear, iterative, projection-based optimization routine. The routine utilizes a projection operator to ensure feasible system trajectories at each iteration of the optimization resulting in valid control signals even when constraints on computation time prevent full convergence. An additional feature of ...