1,720,961 research outputs found
A Client-Server Architecture for Distributed Measurement Systems
Full text linkThis paper describes a client-server architecture for the remote control of instrumentation over the Internet network. The proposed solution allows multiuser, multi-instrument sessions by means of a queueing and instrument locking capability. Client applications can be easily developed by using conventional high-level programming languages or well-assessed virtual instrumentation frameworks. Performance tests are reported; they show the low overhead due to network operation with respect to the direct control of instrumentatio
Electric field strength evaluation of GSM base transceiver station with an analog spectrum analyzer in zero-span configuration
No full textThe paper presents a technique for the evaluation of EM field intensity produced by GSM-like base transceivers. The method is based on the use of an analog spectrum analyzer configured in zero-span mode and in a suitable processing of the analyzer results.
A critical review of some spectrum analyzer characteristics will be also reported showing that in some cases large measurement errors are unavoidable, hence supporting the usefulness of the proposed method.
Experimental results that prove the effectiveness of the technique are reported and discusse
L’incertezza di misura nelle valutazioni del campo elettromagnetico ambientale con l’analizzatore di spettro in modalità zero-span
No full textNelle valutazioni sperimentali del campo elettromagnetico ambientale, l’incertezza di misura è un parametro che assume particolare importanza soprattutto quando i valori misurati approssimano i limiti di esposizione, o i valori di cautela, fissati dalle norme. Sono queste le situazioni che richiedono una maggiore accuratezza, al fine di individuare con particolare dettaglio i punti dello spazio che rispettano, o meno, i limiti fissati.
L’incertezza nelle misure con strumentazione a banda stretta dipende notevolmente da come l’analizzatore di spettro è utilizzato. Nell’utilizzazione tradizionale, basata sulla stima dei livelli massimi dei picchi visualizzati in uscita, è usuale ottenere incertezze elevate, dell’ordine del 50 % o superiori. Diverso è il caso delle misurazioni in modalità zero-span, dove il funzionamento dello strumento non risente delle problematiche riscontrate nell’analisi tradizionale. Con questa metodologia di misura, l’incertezza è un parametro che può essere ridotto in modo considerevole, agendo sia a livello di scelta opportuna di alcuni parametri di setup, sia prevedendo più acquisizioni nel tempo del segnale ricevuto. Quest’ultima possibilità richiede una corretta interpretazione del fenomeno in esame, che è possibile dare in modo completo ed efficace attraverso l’interpretazione statistica dei segnali in gioco
A measurement system for the evaluation of environmental electromagnetic field
No full textThe paper presents a measurement system for the evaluation of electromagnetic (EM) field intensity in large geographical areas. It is based on the combined use of two test stations. The first one is equipped with global positioning system and broadband EM field sensors for preliminary data acquisition. The second test station is based on an analog spectrum analyzer for thorough investigation at locations where large intensity fields are found. The whole system provides geographical maps of the field strength. Control of the measurement subsystems through the Internet network for monitoring purposes is also achieved. Real life experimental data that show the system characteristics are discussed
Un sistema automatico per la realizzazione del catasto elettromagnetico del territorio
No full textNel presente lavoro è illustrato un sistema mobile automatico realizzato e attualmente in funzionamento presso la Provincia Autonoma di Bolzano. Sarà descritta in particolare l’architettura del sistema mobile e l’insieme delle operazioni necessarie al completamento del catasto elettromagnetico sia delle sorgenti di campo, sia degli effetti di queste sul territorio
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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