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https://www.ub.lu.se/accessibility-lup-statistics - 2026-06-25

Fast transient events, such as the disintegration of liquid bodies or chemical reactions between radical species, involve various processes that may occur at different time scales. Currently, there are two alternatives for monitoring such events: burst- or high-speed imaging. Burst imaging at ultrahigh speeds (∼100 MHz to THz) allows for the capture of nature's fastest processes but only for a nar

Using two-pulse photon echo excitation a strong resonance in the measured homogeneous dephasing time as a function of magnetic field is observed in the H-3(4)-D-1(2) transition of Pr3+:YAlO3. The resonance could only be observed at low excitation energies since it otherwise was masked by excitation intensity dependent extra dephasing processes in the crystal. Thus intensity dependent dephasing pro

Fast and reliable time and frequency synchronization is crucial for packet-based orthogonal frequency division multiplex (OFDM) systems. In this paper we compare and analyze preambles for OFDM systems based on repeated OFDM data symbols or repeated short pseudonoise sequences (PN-sequences). We make an analytical evaluation for AWGN channels and simulate the performance in oneand two-tap Rayleigh

Advanced telecommunication applications are often based on a multi-tier architecture, with application servers and database servers. With a rapidly increasing development of cloud computing and data centers, characterizations of the dynamics for database servers during changing workloads will be a key factor for analysis and performance improvements in these applications. We propose a multi-step a

Objectives: To critically evaluate the available evidence base concerned with the diagnosis of pelvic inflammatory disease ( PID) based on clinical presentation, and to investigate the relation between signs and symptoms and the presence of laparoscopically diagnosed PID using the largest available dataset. Methods: The evidence base was critically evaluated and data collected by Lund University b

This technical note investigates the model reduction problem for mean square stable discrete time Markov jump linear systems. For this class of systems a balanced truncation algorithm is developed. The reduced order model is suboptimal, however the approximation error, which is captured by means of the stochastic L2 gain, is bounded from above by twice the sum of singular numbers associated to the

Fault-tolerance is due to the semiconductor technology development important, not only for safety-critical systems but also for general-purpose (non-safety critical) systems. However, instead of guaranteeing that deadlines always are met, it is for general-purpose systems important to minimize the average execution time (AET) while ensuring fault-tolerance. For a given job and a soft (transient) e

This paper investigates the model reduction problem for mean square stable discrete time Markov jump linear systems. For this class of systems a balanced truncation algorithm is developed. The reduced order model is suboptimal, however the approximation error, which is captured by means of the stochastic L2 gain, is bounded from above by twice the sum of singular numbers associated to the truncate

Användandet av soft power i utrikespolitiken är en mycket diskuterad fråga, och i och med presidentskiftet 2009 kom dessa diskussioner att öka. Vi har här undersökt och jämfört George W. Bush och Barack Obamas användande av soft power i respektive utrikespolitik. Vårt fokus ligger på USA:s relationer med Latinamerika och mellanöstern och hur dessa har kommit att förändras. Resultatet visar en stor

PURPOSE OF REVIEW: In the past decades, cysteinyl leukotrienes (CysLTs) and prostaglandin D2 have been recognized as key mediators of asthma and comorbid conditions for their potent broncho-active and proinflammatory properties. However, both the development and initial positioning of small molecules targeting these lipid mediators [i.e., leukotriene-synthesis inhibitors, CysLT-antagonists, and ch

Background: The clinical demarcation of the syndrome progressive myoclonus ataxia is unclear, leading to a lack of recognition and difficult differentiation from other neurological syndromes. Objectives: The objective of this study was to apply a refined definition of progressive myoclonus ataxia and describe the clinical characteristics in patients with progressive myoclonus ataxia and with isola