Normal mode analysis of a rotating group of lashed turbine blades by substructures

A group of 5 lashed identical stream turbine blades is studied through the use of single level substructuring using NASTRAN level 15.1. An altered version, similar to DMAP Program Number 3 of the NASTRAN Newsletter, of Rigid Format 13.0 was used. Steady-state displacements and stresses due to centrifugal loads are obtained both without and with consideration of differential stiffness. The normal mode calculations were performed for blades at rest and at operating speed. Substructuring lowered the computation costs of the analysis by a factor of four

Placing three-dimensional isoparametric elements into NASTRAN

Linear (8 node), parabolic (20 node), cubic (32 node) and mixed (some edges linear, some parabolic and some cubic) have been inserted into NASTRAN, level 15.1. First the dummy element feature was used to check out the stiffness matrix generation routines for the linear element in NASTRAN. Then, the necessary modules of NASTRAN were modified to include the new family of elements. The matrix assembly was changed so that the stiffness matrix of each isoparametric element is only generated once as the time to generate these higher order elements tends to be much longer than the other elements in NASTRAN. This paper presents some of the experiences and difficulties of inserting a new element or family of elements into NASTRAN

Approaches for advancing scientific understanding of macrosystems

The emergence of macrosystems ecology (MSE), which focuses on regional- to continental-scale ecological patterns and processes, builds upon a history of long-term and broad-scale studies in ecology. Scientists face the difficulty of integrating the many elements that make up macrosystems, which consist of hierarchical processes at interacting spatial and temporal scales. Researchers must also identify the most relevant scales and variables to be considered, the required data resources, and the appropriate study design to provide the proper inferences. The large volumes of multi-thematic data often associated with macrosystem studies typically require validation, standardization, and assimilation. Finally, analytical approaches need to describe how cross-scale and hierarchical dynamics and interactions relate to macroscale phenomena. Here, we elaborate on some key methodological challenges of MSE research and discuss existing and novel approaches to meet them

Biodiversity change is uncoupled from species richness trends: consequences for conservation and monitoring

Global concern about human impact on biological diversity has triggered an intense research agenda on drivers and consequences of biodiversity change in parallel with international policy seeking to conserve biodiversity and associated ecosystem functions. Quantifying the trends in biodiversity is far from trivial, however, as recently documented by meta-analyses, which report little if any net change in local species richness through time. Here, we summarise several limitations of species richness as a metric of biodiversity change and show that the expectation of directional species richness trends under changing conditions is invalid. Instead, we illustrate how a set of species turnover indices provide more information content regarding temporal trends in biodiversity, as they reflect how dominance and identity shift in communities over time. We apply these metrics to three monitoring datasets representing different ecosystem types. In all datasets, nearly complete species turnover occurred, but this was disconnected from any species richness trends. Instead, turnover was strongly influenced by changes in species presence (identities) and dominance (abundances). We further show that these metrics can detect phases of strong compositional shifts in monitoring data and thus identify a different aspect of biodiversity change decoupled from species richness. Synthesis and applications: Temporal trends in species richness are insufficient to capture key changes in biodiversity in changing environments. In fact, reductions in environmental quality can lead to transient increases in species richness if immigration or extinction has different temporal dynamics. Thus, biodiversity monitoring programmes need to go beyond analyses of trends in richness in favour of more meaningful assessments of biodiversity change

The Music in \u3ci\u3eHis\u3c/i\u3e Words: The Art of Sound and Folk in Louis Armstrong’s Manuscript for \u3ci\u3eSatchmo: My Life in New Orleans\u3c/i\u3e, “The Armstrong Story”

This thesis dives into the musical journey embedded in the autobiographical writings of America’s jazz ambassador, Louis Armstrong. It examines Armstrong’s typewritten manuscript, The Armstrong Story, which was eventually revised by an editor and published as his second autobiography with the title of Satchmo: My Life in New Orleans in 1954 (originally published in France in 1952.) Armstrong’s manuscript reads like sheet music, where any sound could affect the harmony of the story. He created a voice that had met every art form before it became the manuscript of his autobiography, but along with that voice, references from Black folk and orality were removed by the editor from the published version, separating it from similar works of his time that treasured these features especially. The original manuscript in the Louis Armstrong House Museum Archives bears visual marks, auto-edits, and a dramatic punctuation, providing a layer of meanings and signifiers missing in the published autobiography. His notes outside the manuscript margins tell of an artist on the road; a star living the luxurious minutes of his privacy in front of a typewriter; an ordinary man at his beloved home, a celebrity at the peak of fame, but most importantly they tell of the Black twentieth century genius in the conscious act of introducing folk elements with a transnational impact. Armstrong had elevated these elements in music by delivering traditional songs with virtuosity and versatility, and he had a studious affinity for other essentially traditional songs that had already reached universality like opera or indigenous rhythms. This manuscript is the only one closer to his style that was published while the author was alive. His first, Swing that Music (1936), was heavily edited. This research places the manuscript’s relevance in the study of autobiography: in a larger scope, it intends to classify this example, and other similar cases, when an author’s style has meaning in and of itself, which may have become lost because of editing for publication; in a narrower focus, it expands Armstrong scholarship by highlighting his autobiography’s ontological, anthropological and historic value. Before writing this book, Armstrong had already offered groundbreaking contributions to music with his instrumental and vocal styles, and he brought with him hundreds of references to his New Orleans folk culture, that proved then to challenge the racially integrated society of the 1950s. Referring to Armstrong’s scat singing, Jazz critic Gary Giddins says in Visions of Jazz, “he added scat’s moans and riffs to the palette of conventional song interpretation, employing them to underscore emotion and rhythm and meaning” (86). His writing inherits the form and characters from those “moans and riffs.” It underscores –on the paper as well— “emotion, and rhythm, and meaning”, but its literary value was over-shadowed by his celebrity. New Orleans culture provides a precedent for a writing style that privileges sound, and a narrative that intends to document folk traditions. Deeply rooted in rhythm, a writing style is created from the sound of words – ‘Who dat?’— But Armstrong went further, making a language of his own. It would be inaccurate to call Armstrong’s writing solely a reflection of slang or Black speech. Armstrong used ‘Jive’ talk and jazz music as a compositional style in his lines. He could speak music in a sigh. Armstrong’s is an ideal American success story told in the spirit of Black folk, but that spirit, which brings a much deeper and symbolic legacy, is left on the surface due to his immersion in the mainstream. This thesis identifies an iconic achievement of creative individuality by Armstrong, a Black artist, and proposes a new interpretation of his manuscript that better reads his intentions of preserving folk traditions while making them relevant globally

Danskerne og tech-giganterne: Fra opfattelser til handling

Denne rapport undersøger, hvordan danskerne forholder sig til de såkaldte ”tech-giganter” – både medfokus på danskernes generelle opfattelser, deres bekymringer om tech-giganternes rolle i samfundet,samt konkrete tiltag, danskerne selv tager for at begrænse virksomhedernes indflydelse i hverdagen.Rapporten er en fortsættelse af en række tidligere undersøgelser af danskernes forståelse af, holdningertil og brug af kunstig intelligens, som ligeledes er udgivet af Digital Democracy Centre (DDC) og erbaseret på en repræsentativ spørgeskemaundersøgelse af den danske befolkning.Denne rapport undersøger, hvordan danskerne forholder sig til de såkaldte ”tech-giganter” – både medfokus på danskernes generelle opfattelser, deres bekymringer om tech-giganternes rolle i samfundet,samt konkrete tiltag, danskerne selv tager for at begrænse virksomhedernes indflydelse i hverdagen.Rapporten er en fortsættelse af en række tidligere undersøgelser af danskernes forståelse af, holdningertil og brug af kunstig intelligens, som ligeledes er udgivet af Digital Democracy Centre (DDC) og erbaseret på en repræsentativ spørgeskemaundersøgelse af den danske befolkning

Indeks for det danske digitale demokrati 2024

I denne rapport præsenteres et indeks for det digitale demokratis tilstand i Danmark. Indekset er baseret på to forskellige metoder, der komplemen terer hinanden: en survey med et repræsentativt udsnit af den danske befolkning og en undersøgel se af et udsnit af den danske digitale offentlighed ved brug af forskellige digitale metoder. Med en samlet indeksværdi for de to undersøgelser på hhv. 5,7 og 6,4 på en skala fra 1 til 10 kan vi konkludere, at ”glasset er halvt fuldt”: Grundbetingelserne for det digitale demokrati er på plads med god adgang til internettet og de sociale medier og til de demokratiske institutioner, der er til stede online. Men danskernes deltagelse i og oplevelse af det digitale demokrati viser, at adgang alene ikke er nok, og at potentialet for et stærkt digitalt demokrati ikke fuldt ud omsættes til praksis