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When a target is masked by mainlobe clutter with the same Doppler frequency, it is difficult for conventional airborne radars to determine whether a target is present in a given observation using regular space-time adaptive processing techniques. Different from phased-array and multiple-input multiple-output (MIMO) arrays, frequency diverse arrays (FDAs) employ frequency offsets across the array e

Background: The open abdomen is an innovation that greatly improved surgical understanding of damage control, temporary abdominal closure, staged abdominal reconstruction, viscera and enteric fistula care, and abdominal wall reconstruction. This article provides an evidence-informed, expert, comprehensive narrative review of the open abdomen in trauma, acute care, and vascular and endovascular sur

The authors propose a computationally efficient approach to estimate the directions of arrival of far-field sources impinging on a sensor array. The proposed estimator is formed using a sparse reconstruction framework, employing a novel adaptive grid selection technique to reduce the dimensionality of the used dictionary matrix. The method further makes use of a SPICE-inspired dictionary to adapti

In this paper, we propose a joint transmit and receive antenna selection scheme for frequency diverse array (FDA) radar that aims at finding an optimal selection of employed FDA antennas, formed by minimizing the Cramér–Rao lower bound (CRLB) of the target localization problem given the available a priori knowledge of potential target locations. The resulting problem is a non-convex Boolean proble

Academic debates on law and society relations in authoritarian regimes continue to revolve around issues of the dysfunctional legal system, corruption and informality, clientelistic legal culture, and how the authoritarian regimes in this region deploy law as a means for suppressing dissent. However, in this article, we argue that the legal landscape of authoritarian regimes should not be viewed f

In this paper, we investigate the effects of different augmentation strategies in self-supervised representation learning from electrocardiograms. Our study examines the impact of random resized crop and time out on downstream performance. We also consider the importance of the signal length. Furthermore, instead of using two augmented copies of the sample as a positive pair, we suggest augmenting

In this work, we introduce a novel approach for designing the transmit frequency offset scheme based on Cramér-Rao lower bound (CRLB) minimization for a frequency diverse array multiple-input multiple-output (FDA-MIMO) radar. The problem originates in non-uniform FDA radar where each frequency offset scheme derives from a specific mathematical model, but where no optimization is conducted with res

The polar format algorithm (PFA) is a popular choice for general bistatic synthetic aperture radar (BiSAR) imaging due to its computational efficiency and adaptability to situations with complicated geometries or arbitrary flight trajectories. However, efficient and accurate compensation of 2-D residual phase errors induced by the wavefront curvature remains challenging when obtaining high-quality

This paper addresses the weak signal detection problem in a massive colocated multiple-input multiple-output (MIMO) radar. To cope with the sheer amount of data produced by the large-scale antennas, a low-bit quantizer is introduced in the sampling process to enable both for hardware limitations and a high detection performance. The generalized likelihood ratio test (GLRT) detector is proposed for

Context. To take full advantage of upcoming large-scale spectroscopic surveys, it will be necessary to parameterize millions of stellar spectra in an efficient way. Machine learning methods, especially convolutional neural networks (CNNs), will be among the main tools geared at achieving this task. Aims. We aim to prepare the groundwork for machine learning techniques for the next generation of sp

One of the classical multi-view geometry problems is the so called P3P problem, where the absolute pose of a calibrated camera is determined from three 2D-to-3D correspondences. Since these solvers form a critical component of many vision systems (e.g. in localization and Structure-from-Motion), there have been significant effort in developing faster and more stable algorithms. While the current s

Background: Lead exposure is associated with cardiovascular disease. Atherosclerosis has been hypothesized to be one of the underlying mechanisms behind this association. Aim: To investigate whether lead exposure is associated with an increased risk of atherosclerosis in the carotid arteries in a large Swedish population-based cohort. Methods: We performed a cross-sectional study using data from t

Teachers in the aesthetic program in upper secondary school in Sweden have identified that there are great opportunities and challenges in teaching and working with students who have EDI as their main instrument. From a student perspective it has relevance to being part of meaningful music education developing their musical identity. Students playing EDI can explore an array of electronical musica

Abstract in FrenchLa question qui m’occupe dans cet article est de savoir si une synagogue du premier siècle, comprise à la fois comme une structure construite à cet effet et une institution formelle d’assemblée, se trouvait autrefois à Capharnaüm sous le site de la dernière synagogue en calcaire. J’évalue la question à frais nouveaux en apportant une réflexion méthodologique dans la perspective dThe question with which I am centrally concerned in this article is whether a first-century synagogue, understood as both a purpose-built structure and a formal institution of assembly, once stood in Capernaum beneath the site of its later limestone synagogue. I assess the question anew by providing methodological reflection from the perspective of Collingwoodian critical historiography. In sectio

Mark. Z Danielewski is known for his experiments with the aesthetics of print in works such as House of Leaves and The Familiar. The chapter examines what happens when the experimental book object is digitalized, focusing on the enhanced e-book version of Danielewski’s The Fifty Year Sword. Drawing on theories on remediation (Bolter and Grusin), bookishness (Pressman, Hayles) and digital materiali

In this essay, I offer the first sustained scholarly discussion of the Know Yourself Skeleton Mosaic (KYSM) within its broader cultural milieu and of its contribution to our understanding of self-knowledge in antiquity. In many ways, the mosaic represents an innovative visual "blend" of several cultural tropes and symbols known from the Greco-Roman world. For example, only here is the concept of s