28 research outputs found
Anaerobic digestion of catering wastes
No full textThis research addresses gaps in current knowledge regarding process issues associatedwith long term semi-continuous digestion of food waste as a sole substrate, and the role oftrace elements and biomass retention in digestion of food wastes.Source segregated food wastes were collected from a university catering facility and found,in characterisation studies, to have a total solids (TS) content of 28.1±0.25 %, a volatilesolids (VS) content of 95.5±0.06% of TS and a chemical oxygen demand (COD) of422±16 g kgwet weight -1. The total Kjeldahl nitrogen (TKN) and total lipid content were22±1% and 3.8±0.24% of TS, respectively.The substrate was then processed during a number of digestion trials using mesophiliccontinuously-stirred tank reactors (CSTRs), to establish the suitability of this substrate forCSTR digestion. It was found that although good specific methane production of 0.36 lgVSadded -1 was obtained from the substrate, the process was unstable at a hydraulicretention time (HRT) of 25 days, with methanogenic failure occurring after 80 days orwhen the organic loading rate (OLR) was increased.Further digestion trials were initiated, therefore, to investigate the effects of trace elementsupplementation and extending HRT on process stability, areas for which there is littleinformation in existing literature.Reactors with hydraulic retention times of 25, 30, 50, 100, and 180 days supplementedwith a trace element solution showed stable digestion for longer periods than duplicatecontrol digesters without supplementation. The time points of failure in the controldigesters were shown to be related to washout time, as calculated using the HRT. Traceelement supplementation allowed stable operation at an OLR up to 3.5 gVS l-1d-1, withspecific methane production ranging from 0.41-0.47 l gVSadded -1 and VS destruction of 63-77%.Supplementation with trace elements did not, however, guarantee indefinite stableoperation, as digesters at the shortest (25 days) and longest (180 days) retention timeeventually showed methanogenic failure. A slow methanogenic biomass growth rate andaccumulation of inhibitory substances, respectively, were hypothesised as possible reasonsfor these failures. Analysis of metal concentrations in the digestate showed that cobalt wasthe metal most likely to be responsible for the observed benefits of the mixed trace metalsupplementation as the concentration of this increased in the supplemented digester whilstdecreasing in its non-supplemented control.The relative importance of the liquid and solid fractions in maintaining stability wereinvestigated in novel digestion trials in which solid and liquid retention times wereuncoupled. Digesters with SRT of 25 days and HRT of over 150 days exhibitedmethanogenic failure after approximately 45 days. In contrast, reactors with SRT of over150 days and HRT of 25 days maintained stable digestion, with specific methaneproduction of 0.53 l gVSadded -1, and also showed recovery from a thermal shock appliedduring the experiment. Inhibitory compounds such as VFA were kept low by flushingthrough the system while alkalinity was regenerated by the action of biomass kept in thesystem. The retention of solids may also have facilitated the retention of trace metals
Uncoupling of liquid and solid retention times in anaerobic digestion of catering wastes
No full textSource-separated food wastes collected from a university campus catering facility were processed in bench-scale anaerobic digesters. The feedstock contained a varied mix of fruits, vegetables, meats and fried foods. Two modes of digestion were compared. The first was hydraulic flush (HF) mode, in which liquids were flushed through the reactor on a retention time of 25 days while solids were maintained on an extended retention time of over 150 days. The converse was a solids wastage (SW) mode, in which liquid retention time was over 150 days, and solids were wasted to maintain a retention time of 25 days. SW reactors exhibited methanogenic failure after approximately 45 days. HF reactors, in contrast, maintained stable digestion for a period of 100 days, and were robust enough to recover from a thermal shock applied over a three-day period in which the temperature was increased from 35°C to 50°C between days 105–108 of the experiment. Stable operation was regained by day 139 and continued until the end of the run on day 15
‘What Moves Them’ An investigation into the use of the techniques of Pina Bausch and the strategy of ‘creativity cards’ in the creation of a piece of dance theatre that communicates the brutalities of sex trafficking.
No full textThis thesis documents a process of practice-led research in which I drew on the techniques of Pina Bausch and a particular methodological and choreographic approach to making material – ‘creativity cards’ – in order to create a piece of dance theatre that communicated the brutalities of sex trafficking. The thesis concludes that the form of dance theatre together with the methodology of ‘creativity cards’ and Bauschian techniques such as the use of repetition, the use of ‘violence’ and the use of ‘memeplex’ (a specific characteristic movement species that can be found across Bausch’s work),
enabled me as a choreographer to establish a relationship between the performer and the audience. The combination of form, techniques and methodology used in the research project engaged the audience in such a way that they empathised with the performer and were encouraged to think about what was being presented on stage in The Body Shop. This engagement between audience and performer meant that the project was successful in conveying the brutal realities of sex trafficking
A remark on the phase transition for the geodesic flow of a rank one surface of nonpositive curvature
No full textFor any rank 1 nonpositively curved surface , it was proved by
Burns-Climenhaga-Fisher-Thompson that for any , there exists a unique
equilibrium state for , where is the geometric
potential. We show that as , the weak limit of is the
restriction of the Liouville measure to the regular set
Research in atomic structure: A configuration interaction program with relativistic corrections
No full textAbstract
The RIAS computer program implements the recent formulation for the evaluation of the matrix elements of the complete atomic Hamiltonian operator (S. Fraga et al., Phys. Rev. A 34 (1986) 23). The SL, J or F levels may be obtained by diagonalization of the interaction energy matrix constructed from appropriate SM_S LM_Lfunctions. The program allows for accurate determination of the energy levels of any neutral or ionized atomic system.
Title of program: RIAS
Catalogue Id: ABBB_v1_0
Nature of problem
Determination of the energy levels of any neutral or ionized atomic system.
CORRECTION SUMMARY:
Vol:Year:Page 52:1989:445
"000ACORRECTION 07/09/88"
"Research in atomic structure: a configuration interaction program
with relativistic corrections. (C.P.C. 47(1987)159)."
S. Fraga; M. Klobukowski; J. Muszynska; K.M.S. Saxena; J.A. Sordo; J.D. Climenhaga; P. Clark
Note: correction instructions are contained in source code
Versions of this program held in the CPC repository in Mendeley Data
ABBB_v1_0; RIAS; 10.1016/0010-4655(87)90075-0
This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019
Equilibrium measures for two-sided shift spaces via dimension theory
No full textGiven a two-sided shift space on a finite alphabet and a continuous potential
function, we give conditions under which an equilibrium measure can be
described using a construction analogous to Hausdorff measure that goes back to
the work of Bowen. This construction was previously applied to smooth uniformly
and partially hyperbolic systems by the first author, Pesin, and Zelerowicz.
Our results here apply to all subshifts of finite type and H\"older continuous
potentials, but extend beyond this setting, and we also apply them to shift
spaces with synchronizing words.Comment: 41 page
One-sided almost specification and intrinsic ergodicity
No full textWe define a new property called one-sided almost specification, which lies between the properties of specification and almost specification, and prove that it guarantees intrinsic ergodicity (i.e. uniqueness of the measure of maximal entropy) if the corresponding mistake function is bounded. We also show that uniqueness may fail for unbounded such as . Our results have consequences for almost specification: we prove that almost specification with implies one-sided almost specification (with ) and hence uniqueness. On the other hand, the second author showed recently that almost specification with does not imply uniqueness.</jats:p
(Re)Creation Processes: Milo Rau and the International Institute of Political Murder
No full textIn 2008 Swiss theatre-maker Milo Rau and a group of collaborators founded the production
company the International Institute of Political Murder. Since 2008, Rau and company have
created a unique and identifiable brand of documentary-inspired political theatre. Early IIPM
projects such as Die letzten Tage der Ceausescus (2009) garnered significant attention for their
contribution to the genre of reenactment; however, this early success led to the term reenactment
serving as an umbrella term used to describe Rau’s work. Pulling from the IIPM’s body of work
between 2008 to 2020, (Re)Creation Processes: Milo Rau and the International Institute of
Political Murder identifies and dissects the distinctive organisational categories of the
company’s oeuvre: reenactment (e.g. Hate Radio, 2011), recollection (e.g. Empire, 2016), and
reactment (e.g. Das Kongo Tribunal, 2015). This dissertation offers a broad overview of Rau’s
oeuvre, while also exploring sources for the work. It situates the IIPM’s productions within
historical and contemporary political performance traditions such as lay and artistic reenactment,
documentary theatre, Verbatim theatre, and global artivist performative interventions. Working
with a massive collection of critical and artistic sources, including live and recorded
performances, this study engages in a process of performance and reception analysis, revealing
commonalities and differences between productions and organisational categories. It poses
questions about the use of autoethnography within various production forms, the role
reenactment techniques play across Rau’s oeuvre, the problematic centrality of the director
himself, and ultimately analyses the successes and shortcomings of IIPM productions and
political actions. In an appendix, (Re)Creation Processes also takes an in-depth look at Hate
Radio, closely examining its performance, the text, the source material, and the reception of one
of Rau’s most internationally successful repertoire productions
Marius von Mayenburg's Der Stein: (Un)Covering Memory
No full textMarius von Mayenburg’s Der Stein:(Un)Covering Memory undertakes an in-depth examination of contemporary German playwright Marius von Mayenburg’s 2008 play Der Stein. The play explores how Germany’s National Socialist past continues to play a foundational role within the construction of German identity. However, memory of the past must be critically analyzed because of the fallibility of memory, illustrated in Der Stein. Der Stein is firmly entrenched in the postwar examination of concepts of guilt and responsibility, developed by philosophers such as Hannah Arendt and visible in German popular cultural discourse. Von Mayenburg is a part of a specific movement of German theatre practitioners who embrace a narrative-centered, individualistic, materialist-based theatre aesthetic. Past productions illustrate how this aesthetic lends itself to the complex examination of memory and history present in the structure, motif and themes of Der Stein. The critical reception of productions and the adaptation of the script in performance illustrate the complexity of the play’s structure and the potentiality of meaning within the play. This study proposes Der Stein as an exploration of contemporary theatre practice in Germany. It also investigates the changing relationship between German society and the country’s troubled past, in which the fallibility of memory plays a critical role
Cracking and tension field action in composite beams
No full textTwo aspects of the behaviour of uncased composite 'T' beams of steel
and concrete are considered.
Flexural cracking in the reinforced concrete slab was studied by
subjecting seven 350-mm deep composite beams to hogging bending moment.
Measured strains were found to exceed those calculated from an elastic
analysis ignoring concrete in tension. Also, the first cracks to form in
the slab were much wider than expected. Both of these effects are shown
to be due to drying shrinkage in the slab of the composite beam. A
formula for calculating the mean surface strain in the slab, which allows
for both drying shrinkage and tension stiffening, is proposed.
Consideration of the parameters which affect cracking leads to a
formula for predicting crack widths in composite beams. Comparison with
experimental results shows that it is sufficiently accurate for design
purposes.
In a second series of tests, three 900-mm deep composite plate girders
with slender webs were subjected to combined shear and bending to study
their ultimate load behaviour. Failure was due to the formation of a
plastic collapse mechanism which closely resembles that observed in plain
steel girders under similar loading. The addition of a concrete slab
acting compositely with the girder increased the ultimate strength of the
beam, but variations in the size of the slab and the strength of the
shear connection had negligible effect on the beam's strength.
An idealised collapse model, based on the experimental observations,
is described and is used in the development of a method to calculate the
ultimate strength of composite plate girders. It is shown that a design
method for plain steel girders in the draft Part 3, BS5400 may, with
small modifications, be applied to composite plate girders
