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The MeerKAT radio telescope consists of 64 Gregorian-offset antennas located in the Karoo in the Northern Cape in South Africa. The antenna system consists of multiple subsystems working collaboratively to form a cohesive instrument capable of operating in multiple modes for defined science cases. We focus on the channelizing subsystem (F-engine), the correlation subsystem (X-engine), and the beam
Dynamic resource management is a difficult problem in modern microservice applications. Many proposed methods rely on the availability of an analytical performance model, often based on queueing theory. Such models can always be hand-crafted, but this takes time and requires expert knowledge. Various methods have been proposed that can automatically extract models from logs or tracing data. Howeve
New-particle formation from vapors through molecular cluster formation is a central process affecting atmospheric aerosol and cloud condensation nuclei numbers, and a significant source of uncertainty in assessments of aerosol radiative forcing. While advances in experimental and computational methods provide improved assessments of particle formation rates from different species, the standard app
In this thesis, we present and study a few approaches for constructing controllers for uncertain systems, using a combination of classical control theory and modern machine learning methods. The thesis can be divided into two subtopics. The first, which is the focus of the first two papers, is dual control. The second, which is the focus of the third and last paper, is multiple-input multiple-outp
We present a generic way to obtain level lower bounds for (promise) CSP hierarchies from degree lower bounds for algebraic proof systems. More specifically, we show that pseudo-reduction operators in the sense of Alekhnovich and Razborov [Proc. Steklov Inst. Math. 2003] can be used to fool the cohomological k-consistency algorithm. As applications, we prove optimal level lower bounds for c vs. ℓ-c
In recent years, countries, regions, municipalities and the EU Commission have introduced a significant number of innovation policy initiatives under the banner of ‘missions’, ‘societal challenges’, sustainability, and ‘transformation’, or systemic change. In parallel, there has been a rapidly growing body of literature seeking to analyze or assess these real-world manifestations of attempts to pi
This paper describes a method to compute frame size estimates to be used in quasi Worst-Case Transmission Times (qWCTT) for cameras that transmit frames over IP-based communication networks. The precise determination of qWCTT allows us to model the network access scheduling problem as a multiframe problem and to re-use theoretical results for network scheduling. The paper presents a set of experim
An established rule of thumb in the field of traffic light control prescribes that, during periods of higher demand, it is convenient to have longer cycles. This is in order to reduce the fraction of the cycle length when no incoming lanes receive green light. In this paper, we simulate a novel, provably stable, decentralized feedback traffic light control policy with variable cycle length. The pr
We study a linear quadratic control problem for transportation optimization on a directed line graph. We show that the solution to the Riccati equation associated with this problem is highly structured. The feedback law is almost upper triangular, and the synthesis of the feedback law is given by a recursion, making it scalable. The structure of the feedback law also allows for an efficient realiz
This paper presents a resistor-less high-precision, sub-1 V all-CMOS voltage reference. A curvature-compensation method is used to cancel the logarithmic temperature dependence regardless of mobility temperature exponent (γ). The circuit is simulated in 65 nm CMOS technology and yields an output voltage of 594 mV, temperature coefficient of 7ppm∘C in the range of −40 to 125 °C, a power supply reje
We give a method for designing a mechanical impedance to suppress the propagation of disturbances along a chain of masses. The key feature of our method is that it is scale free. This means that it can be used to give a single, fixed, design, with provable performance guarantees in mass chains of any length. We illustrate the approach by designing a bidirectional control law in a vehicle platoon i
The notion of warping the rate of time is explored in the context of differentially flat systems to enable time-optimal motion by convex optimisation. Examples are given with systems configured on the special Euclidean groups SE(2) and SE(3), with and without differential constraints. The proposed method complements classical methods of motion planning, may be used in a real-time context with guar
We propose and analyze distributed computation algorithms for finite-horizon optimal control problems in transportation networks. We model traffic flow dynamics by the cell-transmission model and focus on two problems: system-optimum dynamic traffic assignment (where the routing is part of the optimization) and freeway network control (where the routing is exogenous and the optimization is confine
Air-to-air refueling is a vital technique for extending the range and endurance of manned or unmanned aircraft, with over 1000 refueling procedures flown per day in military operations. The hardware used for air-to-air refueling needs to be tailored to the specific aircraft and airspeeds involved, performing markedly different for permutations of tanker and receiver craft. Extensive flight testing
The recent explosion in size and complexity of datasets and the increased availability of computational resources has led us to what is sometimes called the big data era. In many big data fields, mathematical optimization has over the last decade emerged as a vital tool in extracting information from the data sets and creating predictors for unseen data. The large dimension of these data sets and
Rotational singularities inherent to three different geometric controllers on SE (3) are studied. A new singularity-free method of incrementally generating a reference rotation is proposed, removing a class of singularities without affecting proven stability properties of the closed-loop systems. If satisfying a bound on attitude rate and maximum loop rate in the reference generation, the proposed
