Search results for "Moda"

Efficient Analysis and Design Strategies for Evanescent Mode Ridge Waveguide Filters

2006

In this paper, a research on the compromises arisen in the design of traditional evanescent mode waveguide filters is carried out. As a result, clear design methodologies for optimizing length, losses, power handling and spurious-free out-of-band response are developed. In addition, an efficient and very accurate modal analysis tool for this kind of structures is presented. Several filters have been designed according to the different strategies proposed, and a prototype has been finally manufactured. Measurements and filter dimensions validate the proposed design procedures.

Multiresolution wavelet-based approach to identification of modal parameters of a vehicle full-scale crash test

2012

In this work estimation of vehicle modal parameters was achieved by application of a wavelet-based method. The time-frequency analysis, which comprises those techniques that study a signal in both the time and frequency domains simultaneously, using Morlet wavelet properties are applied to the measured acceleration pulse of the colliding vehicle. Determination of the ridge of the wavelet coefficients matrix makes it possible to identify the frequency components of the recorded crash pulse. Subsequently, by using the estimated natural frequency of the system, the values of damping factor for a given mode shape are assessed. In this work there are concerned both: the major frequencies of the …

Dynamic identification of a reinforced concrete frame in progressive states of damage

2006

Two, full size, reinforced concrete frames were put on a shaking table and underwent seismic excitations with increasing intensities. The aim of the reported experiment was to study changes in their dynamic, modal parameters due to development of cracks in concrete. Dynamic identification of these frames was carried out through diagnostic tests interlaced with the damaging excitations. This paper presents the results of their identification in various states of damage, using low level non-destructive damage estimation methods. A characteristic decrease of natural frequencies and an increase of structural damping was observed. The drop of the natural frequency was fastest for the 1st mode an…

Combination of modal responses consistent with seismic input representation

2004

The well-known modal superposition method for the evaluation of seismic response by the complete quadratic modal combination rule (CQC) is revisited. The most widely used version of the CQC rule utilizes correlation coefficients derived for white-noise excitation and neglects the influence of peak factor variation on the response. Here a simplified procedure for evaluation of correlation coefficients and peak factors consistent with the power spectral density of seismic excitation is proposed. The procedure is based on an approximate analytic expression for direct evaluation of the power spectral density of the excitation consistent with any prefixed response spectrum, and the evaluation of…

A description model for regeneration through urban tourism in rural towns with underused historic real estate

2016

Il presente contributo propone un modello di descrizione (description model) che trova applicazione in una situazione reale di aiuto alla decisione posto dall'urbanista per lo sviluppo turistico delle città rurali nelle zone dell'entroterra siciliano. Il problema decisionale riguarda la città di Cianciana (AG), che negli ultimi anni si è resa protagonista di un particolare fenomeno di turismo internazionale. In particolare, proponiamo un quadro valutativo multicriteriale per la riqualificazione fisica ed economica del centro storico della città attraverso lo sviluppo del turismo. Il modello presentato, relativo a un problema decisionale di tipo descrittivo, è orientato a supportare i deciso…

Balancing ‘flexibility’ and ‘employability’: The changing role of general studies in the Finnish and Swedish VET curricula of the 1990s and 2010s

2019

This article analyses and compares the evolving role of general subjects in the curricula of initial upper secondary vocational education and training (VET) in Finland and Sweden during the 1990s and 2010s. The research illustrates how Bernstein’s concept of ‘pedagogic code’ supports comparative studies on principles guiding changes to curricula and how the role of general studies in VET has been redefined. The findings show that while a principle of ‘market relevance’ has been central to VET over the decades since the 1990s, it has been subject to varying interpretations. The shifts in interpretations have guided the organisation of VET in these two countries in different directions, incl…

No Entrepreneurship without Opportunity: The Intersection of Return Migration Research and Entrepreneurship Literature

2019

Abstract The article proposes a theoretical discussion at the crossroads of the return migration scholarship with the entrepreneurship research. Its main goal is to build an analytical framework in which entrepreneurial experiences of international return migrants are conceptualized. The fertile theoretical legacy within the study of entrepreneurship along with an idealized view of the positive effects of migration constitute essential premises for understanding the biased outputs of the empirical studies of entrepreneurship upon return to the origin country. Firstly, the article draws on the main lines of theorising opportunities within the Weberian and Schumpeterian theoretical traditions…

Vides aizsardzības kluba darbība 1987-1989

2021

Maģistra darba mērķis ir raksturot Vides Aizsardzības kluba laika periodā no 1987.–1989. gadam un izvērtēt organizācijas nozīmi Latvijas atmodas procesos. Aplūkoto laika periodu raksturo plašas politiskās izmaņas PSRS, kuru rezultāta sākas plašāka sabiedrības iesaiste politiskajos procesos. Pētījumā tiek sniegts ieskats organizācijas priekšvēsturē un izveidē, tās galvenajos darbības virzienos, problēmjautājumos, kuru risināšanā organizācija iesaistījās visplašāk, kā arī iemeslos, kādēļ 1989. gadā klubs nolēma kļūt par apolitisku organizāciju. Maģistra darbā izmantoti Latvijas valsts arhīvā un Zaļās Atmodas muzejā pieejamie materiāli par VAK darbību, tostarp organizācijas dibināšanas materiā…

Epidural spinal abscesses.

1990

Fifteen cases of peridural empyemas are reported. 12 patients reported with motor dysfunction of the lower extremities and pain radiating from the spine. In one case, localized pain of the spine was discovered and in two cases there were no signs of spinal or radiating pain. Treatment in all cases was laminectomy and systemic antibiotic administration. Microbiological analysis showed staphylococcus aureus in 11 cases. 9 patients recovered with no neurological defects, two had major improvement of the paresis, and one died. Three patients with paraplegia recovered from the primary infection.

Modality and Injunctive in Homeric Greek: the case of counterfactual and epistemic constructions

Homeric unaugmented aorists and imperfects are the oldest verbal forms attested in Greek, which continue the so-called Indo-European ‘injunctives’. The latter were inflectionally underspecified as regards verbal categories such as tense or mood (Hoffmann 1967; Kiparsky 1968). Thus, the question arises as to how the attitude of the speaker towards the content of his utterance was expressed. The aim of this paper is to investigate the role of epistemic particles co-occurring with injunctives in the Iliad and the Odyssey, focusing in particular on past counterfactual constructions. Crosslinguistic studies have shown that such modal constructions reflect the universal semantic distinction betwe…