Medium practices

In this essay I develop a topic addressed in my book, Film Art Phenomena: the question of medium specificity. Rosalind Krauss's essay 'Art In the Age of the Post-Medium Condition' has catalysed a move away from medium specificity to hybridity. I propose that questions of medium cannot be ignored, since they carry their own history and give rise to specific formal traits and possibilities. The research involves close critical analysis of four moving image works that have not previously been written about: two made with film, and one each with computer and mobile phone. The analyses are conducted by reference to my ideas about how technological peculiarities inform and inflect practice: I see the work's material composition, its form and final meaning as intricately bound up with each other. Film, video and the computer give rise to specific forms of moving image, partly because artists exploit a medium’s peculiarities, and because certain media lend themselves to some methodologies and not others. I do not seek hard distinctions between these media, but discuss them in terms of predispositions. For example, I discuss a 16mm cine film in which the shifting visibility of grain raises ideas around movement and stillness. The aim is to develop a definition of medium specificity, in relation to the moving image, that is not essentialist in the way previous versions were criticised for being, that is, based on ideas of "material substrate" (Wollen). I argue that film is a medium of stages, in contrast to the modern tapeless camcorder, in which all functions of recording, storage, playback and even editing are contained in a single device. Supported by a travel grant, I presented a version of this essay at the International Conference of Experimental Media Congress, Toronto, in April 2011, along with a selection of works: http://www.experimentalcongress.org/full-schedule

Enhanced Carotenoid Synthesis of Phormidium sp. in Stressed Conditions

Cyanobacteria, also known as blue-green algae or blue-green bacteria obtain their energy through photosynthesis. Phormidium, Filamentous unbranched, non nitrogen fixing, microscopic and later macroscopic up to several cm in diameter, usually covering substrates of different types. Phormidium sp. was selected for the experiment and grown in BG11 medium containing different concentration (0, 1, 2, 3, 4 µg/ml) after the growth period the cells were collected and used to estimate the amount of chlorophyll ‘a’, carotenoids, phycocyanin, free amino acids and proteins in different concentration. An increase in growth period days (0, 2, 4, 6, 8, 10) increase the cellular content namely chlorophyll ‘a’, carotenoids, phycocynin, free amino acids and proteins. Carotenoids are responsible for many of the red, orange and yellow hues of plant leaves, fruits, and flowers as well as the colors of some birds, insects, fish, and crustaceans. The carotenoid content showed positive increase by lowering the nitrogen concentration in which the modified BG11-A medium showed the highest value (85.2 µg/ml) in half strength. It is concluded that enhanced carotenoid synthesis in stressed conditions and it increases two ecological functions, providing photoprotection and increasing photosynthetic performance of surface cyanobacterial populations

Experimental Evidence of Power Efficiency due to Architecture in Cellular Processor Array Chips

Speeding up algorithm execution can be achieved by increasing the number of processing cores working in parallel. Of course, this speedup is limited by the degree to which the algorithm can be parallelized. Equivalently, by lowering the operating frequency of the elementary processors, the algorithm can be realized in the same amount of time but with measurable power savings. An additional result of parallelization is that using a larger number of processors results in a more efficient implementation in terms of GOPS/W. We have found experimental evidence for this in the study of massively parallel array processors, mainly dedicated to image processing. Their distributed architecture reduces the energy overhead dedicated to data handling, thus resulting in a power efficient implementationMinisterio de Economía y Competitividad TEC2015-66878-C3-1-RCentro para el Desarrollo Tecnológico e Industrial IPC- 20111009Junta de Andalucía TIC 2338-2013Office of Naval Research (USA) N00014141035

Experimental archaeology

It is often said that it is easier to learn by doing. This paper explains what experimental archaeology is and shows through examples that it is a viable discipline to be used to increase public appreciation for archaeology and allow a better understanding of what happened in the past. The advantages of applying experimental archaeology in Malta are discussed.peer-reviewe

Experimental Evidence of Power Efficiency due to Architecture in Cellular Processor Array Chips

Speeding up algorithm execution can be achieved by increasing the number of processing cores working in parallel. Of course, this speedup is limited by the degree to which the algorithm can be parallelized. Equivalently, by lowering the operating frequency of the elementary processors, the algorithm can be realized in the same amount of time but with measurable power savings. An additional result of parallelization is that using a larger number of processors results in a more efficient implementation in terms of GOPS/W. We have found experimental evidence for this in the study of massively parallel array processors, mainly dedicated to image processing. Their distributed architecture reduces the energy overhead dedicated to data handling, thus resulting in a power efficient implementationMinisterio de Economía y Competitividad TEC2015-66878-C3-1-RCentro para el Desarrollo Tecnológico e Industrial IPC- 20111009Junta de Andalucía TIC 2338-2013Office of Naval Research (USA) N00014141035

Experimental model of the interfacial instability in aluminium reduction cells

A solution has been found to the long-standing problem of experimental modelling of the interfacial instability in aluminium reduction cells. The idea is to replace the electrolyte overlaying molten aluminium with a mesh of thin rods supplying current down directly into the liquid metal layer. This eliminates electrolysis altogether and all the problems associated with it, such as high temperature, chemical aggressiveness of media, products of electrolysis, the necessity for electrolyte renewal, high power demands, etc. The result is a room temperature, versatile laboratory model which simulates Sele-type, rolling pad interfacial instability. Our new, safe laboratory model enables detailed experimental investigations to test the existing theoretical models for the first time

Analysis strategy for the SM Higgs boson search in the four-lepton final state in CMS

The current status of the searches for the SM Higgs boson in the $H$$\rightarrow$$ZZ^{(*)}$$\rightarrow$$4\ell$ decay channel with the CMS experiment is presented. The selection cuts for suppressing the backgrounds while keeping very high signal efficiencies are described, along with the data-driven algorithms implemented to estimate the background yields and the systematic uncertainties. With an integrated luminosity of $1.66 \mathrm{fb}^{-1}$, upper limits at 95% CL on the SM-like Higgs cross section $\times$ branching ratio exclude cross sections from about one to two times the expected value from the Standard Model in the range $150 < m_{H} < 420 \mathrm{GeV}$. No evidence for the existence of the SM Higgs boson has been found so far.Comment: "Presented at the 2011 Hadron Collider Physics symposium (HCP-2011), Paris, France, November 14-18 2011, 3 pages, 5 figures.

An experimental study of wall-injected flows in a rectangular cylinder

An experimental investigation of the flow inside a rectangular cylinder with air injected continuously along the wall is performed. This kind of flow is a two-dimensional approximation of what happens inside a solid rocket motor, where the lateral grain burns expelling exhaust gas or in processes with air filtration or devices to attain uniform flows. We propose a brief derivation of some analytical solutions and a comparison between these solutions and experimental data, which are obtained using the Particle Image Velocimetry (PIV) technique, in order to provide a global reconstruction of the flowfield. The flow, which enters orthogonal to the injecting wall, turns suddenly its direction being pushed towards the exit of the chamber. Under the incompressible and inviscid flow hypothesis, two analytical solutions are reported and compared. The first one, known as Hart-McClure solution, is irrotational and the injection velocity is non-perpendicular to the injecting wall. The other one, due to Taylor and Culick, has non-zero vorticity and constant, vertical injection velocity. The comparison with laminar solutions is useful to assess whether transition to turbulence is reached and how the disturbance thrown in by the porous injection influences and modifies those solutions

Experimental study of ultracold neutron production in pressurized superfluid helium

We have investigated experimentally the pressure dependence of the production of ultracold neutrons (UCN) in superfluid helium in the range from saturated vapor pressure to 20bar. A neutron velocity selector allowed the separation of underlying single-phonon and multiphonon pro- cesses by varying the incident cold neutron (CN) wavelength in the range from 3.5 to 10{\AA}. The predicted pressure dependence of UCN production derived from inelastic neutron scattering data was confirmed for the single-phonon excitation. For multiphonon based UCN production we found no significant dependence on pressure whereas calculations from inelastic neutron scattering data predict an increase of 43(6)% at 20bar relative to saturated vapor pressure. From our data we conclude that applying pressure to superfluid helium does not increase the overall UCN production rate at a typical CN guide.Comment: 18 pages, 8 figures Version accepted for publication in PR