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Abstract in UndeterminedThis paper presents an inductorless ultra-low power radio receiver front-end intended for applications such as sensor networks and medical implants. It consists of low noise amplifier, quadrature mixer, and a frequency divider for the generation of quadrature local oscillator signals. The power consumption is just 282μW from a 0.9V supply when it operates in the 915 MHz ISM

This paper presents an energy efficient adaptive QR decomposition scheme for Long Term Evolution Advance (LTE-A) downlink system. The proposed scheme provides a performance robustness to fluctuating wireless channels while maintaining lower workload on a reconfigurable hardware. A statistic based algorithm-switching strategy is employed in the scheme to achieve workload reduction and stable comput

We study the notion of structured realizability for linear systems dened over graphs. A stabilizable and detectable realization is structured if the state-space matrices inherit the sparsity pattern of the adjacency matrix of the associated graph. In this paper, we demonstrate that not every structured transfer matrix has a structured realization and we reveal the practical meaning of this fact. W

Three mm-wave pulse generation circuits fabricated in a standard 65nm CMOS process are presented. Two versions are based on the cross-coupled NMOS LC-VCO (500um × 300 um), and one is based on the Colpitts VCO (600um × 300 um). No additional buffers are used in the cross-coupled versions, as they are directly loaded by 50 Ohms through a balun. They can produce measured pulses exceeding 8dBm peak ou

Feedback control has been applied to computing systems, usually taking a designed system and closing a loop to adjust some of its parameters. However, the design of computing systems components as controllers have shown advantages with respect to state-of-the-art techniques, especially in the scheduling domain, where uniprocessor schedulers have been designed as discrete-time control structures. H

Modern hydrological modeling frequently incorporates global remote sensing or reanalysis products for multivariate calibration. Although these datasets significantly contribute to model accuracy, the inherent uncertainties in the datasets and multivariate calibration present challenges in the modeling process. To address this issue, this study introduces an adaptive, process-wise fitting framework

Accurately representing and predicting hydrological processes in terrestrial ecosystems is crucial for understanding the impacts of global environmental change, particularly climate change. This doctoral thesis aims to advance the understanding of vegetation-hydrology interactions and provides new modelling approaches to enhance hydrological prediction abilities. The thesis is grounded in the eval

Tropical oceans are the main global water vapor and latent heat sources, but their responses to radiative forcing remain unclear. Here, we investigate oceanic moisture dynamics of the western tropical Pacific (WTP) over the past 210,000 years through an approach of planktonic foraminiferal triple oxygen isotope (Δ′17O). The Δ′17O record is dominated by the precession cycles (~23,000 years), with l

For decades, the environmental sciences have engaged in measuring and modelling natural systems to increase our understanding and prediction of climate change. This thesis advances these efforts by analyzing and applying in-situ instruments, remote sensing, and modelling approaches. The main focus lies in utilizing a state-of-the-art global Earth System Model (ESM) EC-Earth3, which is used to simu

High-latitude vegetation experience different temperatures than the ambient air temperature. While lacking a regional plant temperature product, we drove the dynamic ecosystem model, LPJ-GUESS, with widely used ERA5-land surface temperature (Tsurf, at radiative equilibrium) and air temperature to understand ecosystem process responses to these two temperatures. We show that tundra plants' growth i

This study investigates seasonal changes in near-surface wind speeds in the Arctic using the regional climate model (RCM) simulations with RCA4 driven by four global climate models (GCMs) CMIP5 under Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. In addition, the RCM RCA-GUESS (RCA4 with interactive vegetation dynamics) is used to investigate the role of biogeophysical feedback

We study the realizability and strong satisfiability problems for SAFETY LTL, a syntactic fragment of Linear Temporal Logic ([Formula presented]) capturing safe formulas. While it is well-known that realizability for this fragment lies in [Formula presented], the best-known lower bound is [Formula presented]-hardness. Surprisingly, closing this gap has proven an elusive task. Previous works have c

Perceiving and understanding human motion is a fundamental problem in computer vision, with diverse applications encompassing sports analytics, healthcare monitoring, entertainment, and intelligent interactive systems. Multi-camera systems, by capturing multiple viewpoints simultaneously, enable robust tracking and reconstruction of human poses in 3D, overcoming limitations of single-view approach