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We extend the generalized information criteria for high-dimensional penalizedmodels to sparse statistical jump models, a new class of statistically robust and computationally efficient alternatives to hidden Markov models. In a simulation study, we demonstrate that the new generalized information criteria selects the correct hyperparameters with high probability. Finally, providing an empirical ap
Two conspicuous wet shifts in the peat stratigraphy of Store Mosse in southern Sweden, associated with bog-wide changes in vegetation and degree of peat decomposition, were analysed at high resolution. The bog-surface wetness (BSW) proxy data (organic matter bulk density, C/N ratio, plant macrofossils and testate amoebae) highlight the importance of interactions between vegetation composition, mic
Building on the base of the existing telescopes of the Event Horizon Telescope (EHT) and ALMA, the next-generation EHT (ngEHT) aspires to deploy ∼10 more stations. The ngEHT targets an angular resolution of ∼15 microarcseconds. This resolution is achieved using Very Long Baseline Interferometry (VLBI) at the shortest radio wavelengths ∼1 mm. The Submillimeter Array (SMA) is both a standalone radio
The atmospheric CO2 growth rate (CGR) variability is largely controlled by tropical temperature fluctuations. The sensitivity of CGR to tropical temperature (γCGRT) has strongly increased since 1960, but here we show that this trend has ceased. Here, we use the long-term CO2 records from Mauna Loa and the South Pole to compute CGR, and show that γCGRT increased by 200% from 1960–1979 to 1979–2000
A simple form for the optimal H-infinity state feedback of linear time-invariant infinite-dimensional systems is derived. It is applicable to systems with bounded input and output operators and a closed, densely defined, self-adjoint and strictly negative state operator. However, unlike other state-space algorithms, the optimal control is calculated in one step. Furthermore, a closed-form expressi
Control theory is one of the key intellectual underpinnings that allows us to analyze the interaction of software with the physical world. However, control theory abstracts software actions as actions that take no time to execute. In reality, software execution takes time – and this execution time can be affected by a number of platform issues, including the speed of the processor, the scheduler u
We introduce a scalable observer architecture to estimate the states of a discrete-time linear-time-invariant (LTI) system whose sensors can be manipulated by an attacker. Given the maximum number of attacked sensors, we build on previous results on necessary and sufficient conditions for state estimation, and propose a novel multi-modal Luenberger (MML) observer based on efficient Satisfiability
Time synchronization is crucial for wireless sensor networks (WSNs), where operations often rely on time ordering of events. WSNs are deployed in different scenarios, and therefore their timing requirements are often related to the peculiar characteristics of the specific environment they have to act in. Synchronization is anyway always an issue: transactional applications need monotonicity of the
A linear parameter-varying (LPV) spectral decomposition method, based on least-squares estimation and kernel expansions, is developed. Statistical properties of the estimator are analyzed and verified in simulations. The method is linear in the parameters, applicable to both the analysis and modeling problems and is demonstrated on both simulated signals as well as measurements of the torque in an
The problem of the orbital stabilization of the forced periodic motions of a non-linear all-wheel drive mechanical system is considered within the framework of a model that is widely used in problems of the planning of the motions and feedback design for industrial robotic manipulators. The basic result is the explicit indication of one of the possible redundant sets of coordinates tranverse to th
Recent findings indicate a strong correlation between the risk of future heart disease and the volume of adipose tissue inside of the pericardium. So far, large-scale studies have been hindered by the fact that manual delineation of the pericardium is extremely time-consuming and that existing methods for automatic delineation lack accuracy. An efficient and fully automatic approach to pericardium
Year-to-year variations in the atmospheric methane (CH4) growth rate show significant correlation with climatic drivers. The second half of 2010 and the first half of 2011 experienced the strongest La Niña since the early 1980s, when global surface networks started monitoring atmospheric CH4 mole fractions. We use these surface measurements, retrievals of column-averaged CH4 mole fractions from GO
N2O is currently the third most important anthropogenic greenhouse gas in terms of radiative forcing and its atmospheric mole fraction is rising steadily. To quantify the growth rate and its causes over the past decades, we performed a multi-site reconstruction of the atmospheric N2O mole fraction and isotopic composition using new and previously published firn air data collected from Greenland an
Complex-valued dynamics can be used for modeling rotationally invariant two-input two-output systems and bandpass systems when they are considered in the baseband. In a few instances, control design has been done in the complex domain, which facilitated analysis and synthesis. While previous work has been application specific, we will discuss more generally how complex valued dynamics arise, basic
Pervasiveness and complexity of modern software are challenging engineers to design applications able to guarantee the desired quality of service despite unpredictable runtime variations in their execution environment. A variety of techniques have been proposed in the last year for the design of self-adaptive applications; however, most of them is tailored to specific applications or can provide l
This paper is about line search for the generalized alternating projections (GAP) method. This method is a generalization of the von Neumann alternating projections method, where instead of alternating projections, relaxed projections are alternated. The method can be interpreted as an averaged iteration of a nonexpansive mapping. Therefore, a recently proposed line search method for such algorith
Many ships today rely on Global Navigation Satellite Systems (GNSS), for their navigation, where GPS (Global Positioning System) is the most well-known. Unfortunately, the GNSS systems make the ships dependent on external systems, which can be malfunctioning, be jammed or be spoofed. There are today some proposed techniques where, e.g., bottom depth measurements are compared with known maps using
This paper considers the implementation and application possibilities of a compact full duplex multiple-input multiple-output (MIMO) architecture, where direct communication exists between users, e.g., device-to-device (D2D) and cellular link coexisting on the same spectrum. For the architecture of the compact full duplex radio, we combine an analog self-interference canceler-based dual polarizati
We can trace the beginnings of our knowledge of early Upper Paleolithic (Aurignacian) use of fire to the pioneering 1910–1911 excavations at Abri Blanchard undertaken by Louis Didon and Marcel Castanet. At Blanchard, the excavators recognized and described fire structures that correspond in many ways to features excavated more recently in Western and Central Europe. Here, we address the issue of h
Marine seismic data are distorted by ghosts as waves propagating upward reflect downward from the sea surface. Ghosts appear on the source side and the receiver side. However, whereas the receiver-side ghost problem has been studied in detail, and many different solutions have been proposed and implemented commercially, the source-side ghost problem has remained largely unsolved with few satisfact
