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In boreal summer, circumglobal Rossby waves can promote stagnating weather systems that favor extreme events like heat waves or droughts. Recent work showed that amplified Rossby wavenumber 5 and 7 show phase-locking behavior which can trigger simultaneous warm anomalies in different breadbasket regions in the Northern Hemisphere. These types of wave patterns thus pose a potential threat to human

This study focused on improving the performance of the near real-time Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) Early Run (IMERG-E) product based on a newly developed bias-correction scheme, LSCDF. The LSCDF was established by integrating the mean-based Linear Scaling (LS) and quantile-mapping Cumulative Distribution Function (CDF) matching approaches. The

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

Motivated by a need to characterize transient behaviors in large network systems in terms of relevant signal norms and worst-case input scenarios, we propose a novel approach based on existing theory for matrix pseudospectra. We extend pseudospectral theorems, pertaining to matrix exponentials, to an input-output setting, where matrix exponentials are pre- and post-multiplied by input and output m

Control systems are by design robust to various disturbances, ranging from noise to unmodelled dynamics. Recent work on the weakly hard model---applied to controllers---has shown that control tasks can also be inherently robust to deadline misses. However, existing exact analyses are limited to the stability of the closed-loop system. In this paper we show that stability is important but cannot be

A new approach to feedback control design based on optimal control is proposed. Instead of expensive computations of the value function for different penalties on the states and inputs, we use a control Lyapunov function that amounts to be a value function of the optimal control problem with suitable cost design and then study combinations of input and state penalty that are compatible with this v

This paper presents a fully integrated 60 GHz frontend for phased array receivers. For the first time in the literature a phase controlled phased locked loop (PC-PLL) is used for beamforming at 60 GHz. The front-end performs a two stage frequency down-conversion, first from 60 GHz to 20 GHz, then from 20 GHz to quadrature baseband. Both the local oscillator signals at 20 GHz and 40 GHz are generat

Over the past years, interest in classifying drivers' behavior from data has surged. Such interest is particularly relevant for car insurance companies who, due to privacy constraints, often only have access to data from Inertial Measurement Units (IMU) or similar. In this paper, we present a semi-supervised learning solution to classify portions of trips according to whether drivers are driving a

Permafrost extends 40% of the Qinghai-Tibet Plateau (QTP), a region which contains the headwaters of numerous major rivers in Asia. As an aquiclude, permafrost substantially controls surface runoff and its hydraulic connection with groundwater. The freeze–thaw cycle in the active layer significantly impacts soil water movement direction, velocity, storage capacity, and hydraulic conductivity. Unde

In market-driven product development, it is important that the software product is released to the market at the right time, and offers higher quality than the competitors. In release planning, the allocation of development effort in investments into product enhancements, functions are competing with quality requirements for limited resources. In addition, it is important to find the right balance

Decision-making is central to Software Product Management (SPM) and includes deciding on requirements priorities and the content of coming releases. Several algorithms for prioritization and release planning have been proposed, where humans with or without machine support enact a series of steps to produce a decision outcome. Instead of applying some specific algorithm to find an acceptable soluti

Reducing the complexity of decoding algorithms for LDPC codes is an important prerequisite for their practical implementation. In this work we propose a reduction of computational complexity targeting the highly reliable codeword bits and show that this approach can be seamlessly merged with the forced convergence scheme. We also show how the minimum achievable complexity of the resulting scheme f

Two branches of gated ring oscillators (GRO) act as the delay lines in 2-dimension Vernier time-to-digital converter (TDC). The proposed architecture reduces dramatically the inherent latency of vernier structure. The already small quantization noise of the standard Vernier TDC is further first-order shaped by the GRO operation. The TDC has been simulated in 90nm CMOS technology. Operating from 50

In this paper, a low-complexity resistorless high-precision sub-1 V MOSFET-only voltage reference is presented. To obtain an accurate output, a curvature-compensation technique is used, canceling its logarithmic temperature dependence regardless of the value of the mobility temperature exponent (γ). The circuit is realized in 65 nm CMOS technology and yields an output voltage of 574 mV, a temperat

This paper presents a robust and low-complexity non-linearity suppression scheme for radio frequency (RF) transceiver building blocks to efficiently mitigate intermodulation distortion. The scheme consists of tunable RF components assisted by an auxiliary path equipped with an adaptive digital signal processing algorithm to provide the tuning control. This proposed concept of digitally-assisted tu