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Modern distribution networks prove to be easily prone to power quality issues, and in particular to the presence of harmonic. components in the voltage and current signals, due to the increasing presence of nonlinear loads, distributed generation, and renewable energy sources. In addition, the non-stationary operating conditions make the problem of harmonic phasors' estimation particularly challenging. The application of Phasor Measurement Units (PMUs) might represent a promising alternative to traditional approaches based on the Discrete Fourier Transform. In this paper, we propose to exploit two estimation techniques derived from recent PMU-based applications and discuss their estimation results in a real-world measurement. dataset, acquired in the medium voltage distribution network of EPFL campus.

Hypoactive-hypoalert behavior (HHB), also termed “psychic akinesia,” is characterized by loss of psychic autoactivation, apathy, and stereotyped activity that are reversed by external stimulation.1 Lesions in the brainstem, basal ganglia, or frontal lobes can underlie HHB.1 We report three patients presenting with HHB due to spontaneous intracranial hypotension (SIH) syndrome. Two men aged 49 and 57 years and a woman aged 60 years were referred by relatives because of a 2-, 5-, and 2-year history of a chronic state of decreased behavioral initiative, persistent somnolence, impaired attention, and stereotyped motor activity. The patients would lie inactive for whole days if left unstimulated, but would perform adequately whenever incited to. They were scarcely concerned about their ensuing family and job problems and did not complain of mood depression, but came to our observation only because urged to by the alarmed relatives. Neurologic examination showed diffuse deep tendon hyperreflexia variously combined with limitation of vertical and vergence eye movements, lateral gaze-evoked nystagmus, and right extensor plantar response. All patients displayed simple motor perseverations such as buttoning or unbuttoning the shirt, rubbing the face, blowing the nose, hand wringing, washing, rubbing or beating the legs or the trunk, or clearing the throat. They denied orthostatic headache. They fell asleep when left undisturbed but could be easily aroused by external stimulations. Neuropsychological tests showed normal findings …

Hardware-in-the-loop (HIL) testing is increasingly recognized as an effective approach for product development. When systems are particularly complex, it may be useful to perform geographically distributed testing when two different parts of the same system are simultaneously tested in two different locations. This paper describes a method to measure real-time signals from geographically distributed locations using a common time base derived from the Global Positioning System (GPS). A high frequency clock is generated by means of FPGA-based modules. The acquired data are then used for a distributed real-time simulation experiment.

This paper deals with the problem of convening the specifications of devices used in measurement systems based on digital signal processing into data that can be represented as probability density functions of the input quantities (samples) in a Monte Carlo procedure for uncertainty estimation. The attention is focused on data acquisition systems and input transducers. Author's proposals for facing this problem are based on the idea of considering separately the different uncertainty contributions, by defining for each of them appropriate pdf's and taking into account the correlation of their effects on the acquired samples to be processed. The advantages and limits of this approach are discussed with the help of experimental tests

MRI showed a cortically-based partially cystic and markedly enhancing mass in the uncus of the right temporal lobe in a patient with long standing refractory partial complex seizures. Histopathological examination revealed a pleomorphic xanthoastrocytoma, a rare, usually benign tumour thought to originate from subpial astrocytes.

Response to sodium lactate infusion has been proposed as a laboratory model for evoking and studying panic attacks and as a possible biological marker for panic disorder (Liebowitz et al. 1984). However, electroencephalogram (EEG) recordings performed during this test yielded contrasting results. Fink et al. (1969) first reported that in five “anxious patients” EEG recording during lactate infusion showed increased β and decreased α bands compared to four healthy controls. Knott et al. (1981) reported a reduction and paradoxical increase of slow waves in six patients with DSM III panic disorder (PD). Lapierre et al. (1984), studying a larger sample of 23 patients with PD and 16 with generalized anxiety disorder (GAD), confirmed the increase of slow waves in the former but failed to find significant differences in the rate of lactate response between the two groups. However these authors did not use a control group of healthy subjects.

MRI findings of bilateral central macrogyria allowed the diagnosis of a congenital variant of Foix-Chavany-Marie syndrome in four patients aged between 13 and 32 years, with facio-pharyngo-glosso-masticatory central diplegia, mental retardation and seizures.

This chapter deals with the study of the voltage and current sensors, that is, the devices used to convert the primary electrical quantities in the power grid into signals that can be properly managed by the input circuits of the Phasor Measurement Unit (PMU). In particular, it is discussed how the use of sensor technologies different from the classical magnetic core instrument transformers (eg, those based on voltage dividers and Rogowski coils) may enable performance much more suited to the metrological behavior required for PMUs in the different practical operating conditions.

Voltage transients are the main causes of complaints for medium-voltage customers, and hence interest is focused on investigation techniques able to help in classifying and localizing such events in accordance with their origin. In this light of fact, a distributed measurement system for performing synchronized acquisition of fast voltage transients is presented in this paper. The system, designed to fulfill specific constraints about the reliability of the provided information, has been used in a one-year long measurement campaign performed in a medium voltage network. The main obtained results are presented.