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Fil: Leonardi, Rodrigo Jorge. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. La biotecnología aplicada al cultivo de microalgas crece a pasos agigantados, producto de que la composición de la biomasa puede ser adaptada a fines específicos, entre los más destacados, alimentación humana y abastecimiento de energía para garantizar la seguridad social. Si bien se cultivan microalgas a escala industrial, las productividades y eficiencias alcanzadas se encuentran muy por debajo de las teóricas, y las obtenidas en laboratorio. La energía radiante es considerada el factor más influyente en el crecimiento de organismos fotosintéticos, y es utilizada como parámetro en las etapas de síntesis y escalado de bioprocesos. En la presente Tesis se propone estudiar los efectos de la calidad, la cantidad y la distribución de la radiación sobre la conducta de suspensiones de microalgas en fotobiorreactores. A través de ensayos de laboratorio, en condiciones de iluminación diseñadas y controladas, se puede obtener información (experimental y computacional, producto del modelado del campo de energía radiante) acerca de la conducta de las microalgas en sistemas de cultivo outdoor. Se dedica especial atención al desarrollo de herramientas predictivas, basadas en simulación computacional y cultivo en laboratorio, de la performance de reactores de mayor escala iluminados con luz solar, una energía renovable de costo nulo. Contar con metodologías de laboratorio rápidas y precisas, para estimar la productividad de cepas de microalgas en reactores varios, permite evitar gastos de tiempo y dinero asociados al diseño, puesta en funcionamiento y escalado de bioprocesos. Microalgae biotechnology has achieved significant advances over the last years, due to its interest as a source of molecules used in pharmaceutical, cosmetic and food industry, or alternative energy production. Although microalgae are grown at industrial scale at present, the productivity and efficiency achieved are well below than the theoretical ones, and those obtained at laboratory scale. Radiant energy is considered the most important factor for photosynthetics organism growth, and it is used as a key parameter in the scaling up stage of bioprocesses. We studied the effect of light quality, quantity and distribution on microalgae growth inside photobioreactors. Under controlled lighting conditions, we could obtain experimental and computational information (by modelling of radiant energy field) about the behavior of microalgae in outdoor culture systems. We specially focused at predictive tools development to improve the large-scale reactors performance illuminated with sunlight. Fast and precise laboratory methodologies to estimate the productivity of microalgae strains in photobiorreactors avoids spending time and money for design, commissioning, and scaling up of bioprocesses. Consejo Nacional de Investigaciones Científicas y Técnicas Universidad Nacional del Litoral

CubeSats have become an interesting innovation in the space sector. Such platforms are being used for several space applications, such as education, Earth remote sensing, science, and defense. As of May 31st, 2018, 855 CubeSats had been launched. Remote sensing application is the main sector in which CubeSats are being used, corresponding to about 45% of all applications. This fact indicates the commercial potential of such a platform. Fifty eight countries have already been involved with developing CubeSats. The most used CubeSat configuration is 3U (about 64%), followed by 1U (18%), while 6U platforms account for about 4%. In this paper, we present an analysis of the current situation regarding CubeSats worldwide, through the use of a dataset built to encompass information about these satellites. The overall success rate of the CubeSat missions is increasing over time. Moreover, considering CubeSat missions as a Bernoulli experiment, and excluding launch failures, the current success rate was estimated, as a parameter of a binomial distribution, to be about 75%. By using a logistic model and considering that the launchings keep following the current tendency, one can expect that one thousand CubeSats will be launched in 2021, within 95% certainty.

This test was devoted to characterise the i-V response of LNAs when Vg1 and Vg2 are independently changed over a defined set of values. In the specific, It was aimed at investigating possible changes in the response from radiometers due to ground shift or any other possible non ideal effect. In the case that any results were sensibly different respect to the same test in CSL, the new I -V curves shall be used to modify/correct the drain current model used to draw the PRE- Tuning hyper-matrixes, according to the measured bias shift.

Planck LFI Commissioning and Performance Verification (CPV) Tuning of the LFI has been accomplished at several stages of integration, with different procedures. During these procedures, the system noise temperature (Tsys) and isolation have been used as the figures of merit for optimising performance, since they can be estimated with high signal-to-noise in a short period of time. In fact, for the LFI receivers, the calibrated noise and 1/f characteristics are the true indicators of scientific performance. In principle, calibrated white noise can be derived directly from the system temperature and noise effective bandwidth, but in practice there are noise contributions and other complications which make it hard to be sure that white noise predicted by Tsys and bandwidth will be achieved. With a receiver topology as complex as LFI, it is even possible that optimising Tsys and isolation may cause us to miss the actual optimum white noise bias point. With this in mind, we developed the following verification test based on the Hypermatrix tuning: set LFI for nominal operations (DAE gain and offset tuned to allow measurement of the true radiometer white noise); acquire data (30 seconds) at each of the nominal hypermatrix tuning bias points, in the same manner as was done for the hypermatrix tuning; change the 4K load temperature by a known amount; again acquire data at all the hypermatrix bias points; white noise is estimated from each 30 second period, and then calibrated using the corresponding data from the known temperature step of the 4K load.

Planck LFI Commissioning and Performance Verification (CPV) The assessment of the noise properties of the LFI instrument is the main objective of this test. The test is split into two parts. In the first part, the LFI is run unswitched acquiring data in all four phase switch configurations. Power spectra from unswitched data is compared in order to assess whether there is any configuration that is preferable from the point of 1/f noise slope. In the second part, the LFI is run switched for several hours and the full noise properties are characterised in both switching configurations (A/C or B/D) while the non-switching phase switch is kept in its nominal position.

Planck LFI Commissioning and Performance Verification (CPV) This document describes the results of the Hypermatrix pre–tuning activities. The pre–tuning is aimed at exploring the LNAs bias space changing simultaneously the four Vg biases powering each radiometer, in order to focus the bias region expected to provide the best performance. Noise Temperature is the figure of merit. It is measured roughly by calculating Y factor based on the sky – ref unbalancing over the same BEM diode when the 4KHz switching is enabled. Previous tests conducted on data from CSL campaign demonstrated that a good agreement between this rough calculation and the true Y-factor method ( basing on two reference temperatures provided by the 4K stage cooldown) is achievable.

Planck LFI Commissioning and Performance Verification (CPV) This document summarises the results obtained during the commissioning tests performed on the LFI integrated on the Planck satellite. Tests have been conducted from June the 4th 2009 to June 26th 2009. Details of the performed activities are discussed in specific reports that will be available after the CPV.

Planck LFI Commissioning and Performance Verification (CPV) Spurious frequency spikes at the fundamental frequency of 1 Hz are known to be present in the LFI scientific data caused by an anomalous interaction between the DAE housekeeping sequencer and the scientific channels. The effect is a spurious signal that adds to the radiometric output after detection and is characterized by frequency spikes at the fundamental frequency of 1 Hz. These spikes are characterized by a series of tests run during all the test campaign in order to check this effect in different situations. Tests performed on ground at satellite level have shown that the effect of these spikes on the LFI science is expected to be very small; therefore the main objectives of the same tests performed during CPV is to compare results with those obtained during the CSL test campaign.

Planck LFI Commissioning and Performance Verification (CPV) The purpose of this test is to characterize the dynamic behaviour of the LFI Focal Plane with no active control of the TSA temperature, evaluate transfer functions between FPU sensors and compare results with previous tests and thermal model predictions.

Planck LFI Commissioning and Performance Verification (CPV) This test consists of a 12-hours data acquisition performed with the instrument set with “CRYO” biases, i.e. the biases that have been obtained in CSL after the tuning activities. The objective of this test is to verify the readiness of the instrument for the CPV bias tuning activity from the signal stability point of view. As during this test the 4K temperature was still around 20 K and the stability was not optimized yet the check on knee frequency is meaningful just from the functionality point of view. No comparison is done between the calculated knee frequencies and the LFI scientific requirements.

Planck LFI Commissioning and Performance Verification (CPV) The SCS PID will be used to characterise the radiometers front-end thermal susceptibility (THF). The temperature of the LFI focal plane (FPU) is changed over 4 values, each step having a duration > 3h, depending on the step. The temperature variations are of about 0.3 K each. The measured receivers output will be characterized as a function of FPU temperature variations.

Planck LFI Commissioning and Performance Verification This test was devoted to characterizing the i-V response of LNAs when Vg1 and Vg2 are independently changed over a defined set of values. In the specific, It was aimed at investigating possible changes in the response from radiometers due to ground shift or any other possible non-ideal effect. In the case that any results were sensibly different with respect to the same test in CSL, the new I-V curves shall be used to modify/correct the drain current model used to draw the PRE- Tuning hyper-matrixes, according to the measured bias shift.

Planck LFI Commissioning and Performance Verification (CPV) This document describes the activities performed during the first phase switch (PSW) tuning and verification test performed during CPV. The objective of this test, composed of two steps, is to find the optimal bias currents to the front-end phase switches that balance the wave amplitude in the two-phase switch states. An optimal balance has an impact on the receiver isolation, therefore the first part of the test (P_PVP_LFI_0004_01, namely tuning) was performed before the tuning of the front-end modules amplifiers. The second part (P_PVP_LFI_0004_02, namely verification) was performed after the tuning of the front-end modules to verify the impact on phase switch balancing of different amplifiers biases. The test was performed only on 30 and 44GHz RCAs as planned.

Planck LFI Commissioning and Performance Verification (CPV) This document describes the results from the Functionality Reference Test (FRT) The FRT is composed of two parts, devoted to different tasks. The first part is identical to the CRYO 02: it is devoted to checking the functionality of radiometers in all the possible phase switch and 4KHz combinations, after the HYM Tuning (that was considered a possible source of stress for radiometers) and to compare with it. In particular, the LNAs drain currents will be compared, together with the noise properties as 1/f, white noise, spikes. The output voltage can be compared just roughly considering the sky signal, because the ref signal decreases due to 4K cooler cooldown: this rough comparison must take into account possible differences in the SCS temperature ( driving the FPU temperature and hence the LNAs gain) and the radiometers Isolation ( the signal leaking from the Reference loads and mixing with the Sky signal is proportional to the Reference Load temperature). The second part is identical to the same test performed in CSL (Liege , 2008), but is performed with the LNAs bias set to the final configuration outcome from the HYM Tuning. This test, similar from the procedural point of view to the CRYO 01, is devoted to setting a reference point for the future of the survey, characterizing one by one all the LNAs measuring both the scientific output and the bias ( drain currents). This is operation can be repeated at any time during the survey, with a minimum effect on other channels not under test.

Planck LFI Commissioning and Performance Verification (CPV) This test consists in five steps, of about 15 minutes, with different blanking times: 7.5 µιχρο−s, 0 µιχρο−s, 15 µιχρο−s, 22.5 µιχρο−s, and again 7.5 µιχρο−s. In particular, we want to verify that: no current drops or abrupt variations are observed in FEM drain currents; no frequency spikes are observed besides those already characterised during the SPIKE-02 test; frequency spikes are not affected by the different blanking time values; no pop-corn noise is detected in radiometer voltage outputs.

Planck LFI Commissioning and Performance Verification (CPV) In this report, we show the results of the DAE calibration activity performed during the CPV test phase of the Planck/LFI instrument. The activity has the purpose of finding the best gain and offset values for the 44 ACA implemented in the LFI, and characterizing the so-called “offset problem”, i.e. a spurious offset that the DAE applies to scientific data under some conditions. During the CPV phase, the DAE calibration has been repeated twice, because after the first calibration a new configuration for the LFI ACA biases has been loaded and the absolute voltage levels fed to the DAE have changed consequently. This document shows the results for both calibrations.

Planck LFI Commissioning and Performance Verification (CPV) This document describes the activities performed during the CRYO_02 functionality test. This test consists in two hours of data acquisition in which the radiometers are run in switching mode and during which all four possible phase switch configurations are tested. The objective of this test is to verify that the radiometers are functional from the point of view of the front-end amplifiers and that the pseudo-correlation differential scheme is effective in reducing 1/f noise instabilities.