Alta Gracia, Argentina

Air University Institute
Alta Gracia, Argentina
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Zhang Y.,ShenYang Agricultural University | Zhang Y.,Lanzhou Jiaotong University | Luo G.,Lanzhou Jiaotong University | Cao Q.,Harbin Institute of Technology | Lin M.,Air University Institute
International Journal of Non-Linear Mechanics | Year: 2014

In this paper, we examine a shallow arch model with viscous damping subjected to a sinusoidally varying central load. The system can possess more than 20 coexisting low-period periodic attractors for a given set of parameters. The large number of stable orbits yields a complex structure of closely interwoven basins of attraction, whose boundaries fill almost the whole state space. We describe the Wada basin boundaries and partially Wada basin boundaries by the mathematically rigorous method for some basins. The consequence is the existence of a high number of possible final states and the difficulty of predicting the finial states. Perturbations in such a system render uncertainty even the qualitative fate of a given initial state. © 2013 Elsevier Ltd.

Rivilli P.L.,Air University Institute | Alarcon R.,National University of Salta | Isasmendi G.L.,National University of Salta | Perez J.D.,National University of Cordoba
BioResources | Year: 2012

Pyrolysis of peanut shells was carried out using stepwise isothermal fast pyrolysis (SIFP). SIFP consists of successive isothermal fast pyrolysis reactions, where solid products obtained in the previous isothermal fast pyrolysis become the substrate of the subsequent reaction at a higher temperature. This article reports results obtained from SIFP of peanut shells between 200 and 300°C using 100°C intervals under vacuum (0.2 mm). The maximum yield of liquid products was obtained at 300°C, giving around 30% of bio-oil, which contained mainly phenols and furan derivatives. On the other hand, since previous papers have reported fungicidal activity of phenols derivatives from lingo-cellulosic biomass pyrolysis, we carried out antifungal activity tests of bio oil obtained from peanut shells SIFT at 300 °C. Results seem promising, at least on Sclerotium rolfsii.

Liu Q.J.,Air University Institute | Han F.,Air University Institute
Applied Mechanics and Materials | Year: 2014

In order to study the effect on heat transfer performance of evaporator in the gravity feed liquid refrigeration system the different evaporator area, the simulation procedure is worked out. The procedure uses the visual basic language. The procedure can figure out the heat transfer coefficient and the temperature difference in different evaporator area and evaporating temperature with the required refrigerating capacity. Through simulation calculation, when the area is 80% of the original design area of evaporator, the evaporator of the heat transfer coefficient and heat transfer temperature difference is the most reasonable and the evaporator of the refrigerating capacity can meet the requirements of cold storage. The program provides the reliable data for the gravity feed liquid cooling system optimization. © (2014) Trans Tech Publications, Switzerland.

Murdoch S.,Air University Institute | Reynoso S.,Air University Institute
IEEE Latin America Transactions | Year: 2013

This paper presents a maximum power point tracking (MPPT) circuit for an Unmanned Air Vehicle. The design of the MPPT is proposed utilizing a boost-converter topology. The power of the photovoltaic cells is monitored by a closed-loop microcontroller based control system, and the PWM signal of the boost converter continuously adjusted to extract maximum power. The MPPT is used to charge the Lithium-ion Polymer battery and feed the electrical load of the unmanned aircraft. © 2003-2012 IEEE.

Brito M.,Air University Institute | Rodriguez S.,Air University Institute
IEEE Latin America Transactions | Year: 2013

This paper briefly describes a six degree of freedom simulator code characteristics and the nSat-IE satellite structural configuration, which fulfills two missions: data recovery and to be a technology development workbench. Besides this, this simulator will be used as a tool in order to obtain and study the results from the spacecraft orbit behavior. Two orbit simulation cases will be of paramount importance to check the code operation. It will be introduced as well a 3D satellite model (in development stage) witch take data from the simulator code in order to visualize the satellite when orbiting the earth. This 3D model is being developed using OpenGL and it will be coupled to the simulator code. © 2003-2012 IEEE.

Grispino A.S.,Air University Institute | Petracca G.O.,Air University Institute | Dominguez A.E.,Air University Institute
IEEE Latin America Transactions | Year: 2013

In Electronic Warfare the goal of the attacker is interfering with communications of his adversary. A common type of attack is Jamming which corrupts the electronic devices signals by introducing intentionally different kinds of noise. In particular, in the context of radar systems, the attackers actions tend to avoid detection by the radar system. In this paper we carry out the signal processing of pulse radar in the presence of brown noise by two different digital filters: Discrete Wavelet Transform, DWT and Empiric Mode Decomposition, EMD. From the comparison between both results we obtain that EMD filtering is much more effective than DWT filtering for the situation described above. © 2003-2012 IEEE.

Curetti M.,Air University Institute | Garcia Bravo S.,Air University Institute | Arri G.S.,Air University Institute | Mathe L.,Air University Institute
IEEE Latin America Transactions | Year: 2013

This paper presents an adjustable algorithm for object tracking in a sequence of images. It is a method designed to be effective in applications where some of the information on the object tracked is known. To establish the object position and size in a frame, adaptive template matching, location prediction through known trajectory, border information in the image, and data acquired in previous frames are used. This algorithm behaves nicely with sequences of images where the tracked object size and features vary considerably. It is also robust to some levels of occlusion, and it can be adapted to simpler applications to compete in speed with a basic correlation algorithm. © 2003-2012 IEEE.

Garbariene I.,Lithuanian Academy of Sciences | Kvietkus K.,Lithuanian Academy of Sciences | Sakalys J.,Lithuanian Academy of Sciences | Ovadnevaite J.,Air University Institute | Ceburnis D.,Air University Institute
Journal of Atmospheric Chemistry | Year: 2012

An Aerodyne quadruple aerosol mass spectrometer (Q-AMS) has been used to provide on-line measurements of size dependent chemical composition of fine aerosol particles (PM1) at the Air Pollution Research Station in Preila, Lithuania, representing the east Baltic region. The size dependent chemical composition measurements by AMS have revealed that in marine air masses 118 nm mode organics-containing particles were fresher compared to sulfate-containing particles (295 nm), likely originated as secondary aerosol from forest emissions or produced by primary sea spray over the Baltic Sea. In polluted continental air masses sulfate and organics were highly internally mixed and aged. The mass spectral results indicated that the major components of organic compounds were oxygenated organic species with strong signals at m/z 18, 43, 44 with several specific features. Positive matrix factorization (PMF) of AMS organic mass spectral data has identified three factors: aged oxygenated low-volatility organic aerosol (LV-OOA), less oxygenated semi-volatile organic aerosol (SV-OOA), and biogenic organic aerosol (BGOA) of either terrestrial or marine origin. The measurements were compared with a real-time particulate matter Beta Absorption Monitor (Thermo ESM Andersen) and Micro Orifice Uniform Deposit Impactor (MOUDI) data. The intercomparison showed a good correlation and a stable ratio between PM1 and PM2.5 concentrations. A comparison of the on-line Q-AMS data and the off-line MOUDI fine particle (<1 μm) data yielded a reasonable agreement in size distributions but not the absolute mass concentrations due to sampling conditions, evaporation of acidic species from sampling substrates and bounce of the particles in the MOUDI. © Springer Science+Business Media B.V. 2012.

Wang Y.-W.,Air University Institute | Wang G.-M.,Air University Institute | Zong B.-F.,Air University Institute
IEEE Antennas and Wireless Propagation Letters | Year: 2013

The conventional Vivaldi antenna is known for its ultrawideband characteristic, but low directivity. In order to improve the directivity, a double-slot structure is proposed to design a new Vivaldi antenna. The two slots are excited in uniform amplitude and phase by using a T-junction power divider. The double-slot structure can generate plane-like waves in the E-plane of the antenna. As a result, directivity of the double-slot Vivaldi antenna is significantly improved by comparison to a conventional Vivaldi antenna of the same size. The measured results show that impedance bandwidth of the double-slot Vivaldi antenna is from 2.5 to 15 GHz. Gain and directivity of the proposed antenna is considerably improved at the frequencies above 6 GHz. Furthermore, the main beam splitting at high frequencies of the conventional Vivaldi antenna on thick dielectric substrates is eliminated by the double-slot structure. © 2002-2011 IEEE.

Stein A.F.,Air University Institute | Draxler R.R.,Air University Institute | Rolph G.D.,Air University Institute | Stunder B.J.B.,Air University Institute | And 2 more authors.
Bulletin of the American Meteorological Society | Year: 2015

The National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory's (ARL) Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) is a complete system for computing simple air parcel trajectories as well as complex transport, dispersion, chemical transformation, and deposition simulation. The scientific foundation and inspiration for HYSPLIT's trajectory capabilities can be traced back to 1949, when the Special Project Section (SPS) of the U.S. Weather Bureau was charged with trying to find the source of radioactive debris originating from the first Soviet atomic test and detected by a reconnaissance aircraft near the Kamchatka Peninsula. Recently, a global Eulerian model was included as a module of the HYSPLIT modeling system. Back-trajectory calculations have been one of the most attractive and prominent features by which HYSPLIT has been used in many studies. However, coupling the back-trajectory calculation with a Lagrangian dispersion component can produce a more realistic depiction of the link between the concentrations at the receptor and the sources influencing it.

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