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In this paper, using tools from graph theory we provide verifiable necessary and sufficient conditions for the existence of a unique hydraulic equilibrium in district heating systems of meshed topology and containing multiple heat sources. Even though numerous publications have addressed the design of efficient algorithms for numerically finding hydraulic equilibria in the general context of water

The formation of platoons, where groups of vehicles follow each other at close distances, has the potential to increase road capacity. In this paper, a decentralized control approach is presented that extends the well-known constant headway vehicle following approach to the two-dimensional case, i.e., lateral control is included in addition to the longitudinal control. The presented control scheme

The variations of atmospheric Δ14C over the past two millennia are classically attributed to changes in its production rate in the upper atmosphere, which in turn is related to changes in solar activity and the Earth's magnetic field. However, the potential contribution of atmospheric and oceanic circulation changes during this period has not been precisely quantified. This has been achieved here

This study investigated the applicability and performance of a hydrological model (namely FLEXG) for simulating streamflow in boreal catchment, exemplified by the representative Krycklan catchment. The FLEXG simulated daily streamflow for the whole catchment and its sub-catchments. The Kling-Gupta Efficiency (KGE) and Nash-Sutcliffe Efficiency (NSE) demonstrated favorable model performance during

Uppenbarelseboken avtäcker med sina fasansfulla syner – sin Apokalyps – vad som ska ske på den yttersta dagen, då allt ont ska förgås och ett nytt rike ska upprättas. Men numera menas ofta med apokalyps enbart den skräckfyllda, mytologiska spådomen om en framtida katastrof. Kan man istället förstå Uppenbarelsebokens syner som en varning, för den katastrof vi själva är med om att skapa här och nu,

Traditional phase scan method for cavity phase and amplitude setting is offline and hard to track the variations of environment and operation points. An alternative beam loading based calibration method is investigated in this paper, which might become useful online/real time calibration method.

The higher efficiency and higher availability (fault-tolerant oriented) of RF & Cavity system (with beam loading) to operate at, the more dynamic details needs to be identified, so as to have the abilities (a) to work at nonlinearities, (b) to work close to limitation, and (c) to change operation point quickly and correctly. Dynamic detail identifications rely heavily on high precision measuri

This paper present a 6DoF-positioning method and shape estimation method for cars from monocular images.We pre-learn principal components, using Principal Component Analysis (PCA), from the shape of cars anduse a learnt encoder-decoder structure in order to position the cars and create binary masks of each camera instance. The proposed method is tailored towards usefulness for autonomous driving a

Historically, aerosols of anthropogenic origin have offset some of the warming from increased atmospheric greenhouse gas concentrations. The strength of this negative aerosol forcing, however, is highly uncertain-especially the part originating from cloud-aerosol interactions. An important part of this uncertainty originates from our lack of knowledge about pre-industrial aerosols and how many of

We present a unique comparative analysis, and evaluation of vision, radio, and audio based localization algorithms. We create the first baseline for the aforementioned sensors using the recently published Lund University Vision, Radio, and Audio (LuViRA) dataset, where all the sensors are synchronized and measured in the same environment. Some of the challenges of using each specific sensor for in

Volcanic eruptions are documented throughout geological history and are frequently observed and experienced in the modernworld. Strong eruptions in recent decades have resulted in air and water pollution, acid snowfall, disruption in aerial transport and variousillnesses in humans and livestock. Despite their consequences, these recent events are incomparable to eruptions of a much largermagnitude

Radiocarbon dating provides a key chronological framework for studying past environmental changes. Raw radiocarbon ages measured in samples must be converted to calendar ages using an appropriate calibration curve. Tree-ring datasets provide the gold-standard for developing a precise curve of atmospheric radiocarbon levels over long-time scales. Here, we reconstruct atmospheric radiocarbon levels

Reliable information on solar activity over the Holocene period is important to predict the Sun in the future and to understand the mechanism behind the Sun-climate linkage. Presently, there are discrepancies in the proxy data of solar activity due to reasons that are not yet understood. This leads to major uncertainties in Holocene solar reconstructions. This PhD project aims to improve the Holoc

Extreme solar particle events (ESPEs) are rare and the most potent known processes of solar eruptive activity. During ESPEs, a vast amount of cosmogenic isotopes (CIs) 10Be, 36Cl, and 14C can be produced in the Earth's atmosphere and deposited in natural stratified archives. Accordingly, CI measurements in these archives allow us to evaluate particle fluxes during ESPEs. In this work, we present a

We present an age model for the 651g€¯m deep ice core from Skytrain Ice Rise, situated inland of the Ronne Ice Shelf, Antarctica. The top 2000 years have previously been dated using age markers interpolated through annual layer counting. Below this, we align the Skytrain core to the AICC2012 age model using tie points in the ice and air phase, and we apply the Paleochrono program to obtain the bes

A central goal of education is to improve argumentation literacy. How do we know how well this goal is achieved? Can we measure argumentation literacy? The present study is a preliminary step towards measuring the efficacy of education with regards to argumentation literacy. Tests currently in use to determine critical thinking skills are often similar to IQ-tests in that they predominantly measur

The IntCal family of radiocarbon (14C) calibration curves is based on research spanning more than three decades. The IntCal group have collated the 14C and calendar age data (mostly derived from primary publications with other types of data and meta-data) and, since 2010, made them available for other sorts of analysis through an open-access database. This has ensured transparency in terms of the

The Sun is magnetically active and often produces eruptive events on different energetic and temporal scales. Until recently, the upper limit of such events was unknown and believed to be roughly represented by direct instrumental observations. However, two types of extreme events were discovered recently: extreme solar energetic particle events on the multi-millennial time scale and super-flares

We define a ray, show how to use ray intervals, and demonstrate how to specify a ray using DirectX Raytracing (DXR).