2,300 research outputs found
Thin and thick cloud top height retrieval algorithm with the Infrared Camera and LIDAR of the JEM-EUSO Space Mission
The origin of cosmic rays have remained a mistery for more than a century.
JEM-EUSO is a pioneer space-based telescope that will be located at the
International Space Station (ISS) and its aim is to detect Ultra High Energy
Cosmic Rays (UHECR) and Extremely High Energy Cosmic Rays (EHECR) by observing
the atmosphere. Unlike ground-based telescopes, JEM-EUSO will observe from
upwards, and therefore, for a properly UHECR reconstruction under cloudy
conditions, a key element of JEM-EUSO is an Atmospheric Monitoring System
(AMS). This AMS consists of a space qualified bi-spectral Infrared Camera, that
will provide the cloud coverage and cloud top height in the JEM-EUSO Field of
View (FoV) and a LIDAR, that will measure the atmospheric optical depth in the
direction it has been shot. In this paper we will explain the effects of clouds
for the determination of the UHECR arrival direction. Moreover, since the cloud
top height retrieval is crucial to analyze the UHECR and EHECR events under
cloudy conditions, the retrieval algorithm that fulfills the technical
requierements of the Infrared Camera of JEM-EUSO to reconstruct the cloud top
height is presently reported.Comment: 5 pages, 6 figures, Atmohead Conference 201
Behavior of tumors under nonstationary theraphy
We present a model for the interaction dynamics of lymphocytes-tumor cells
population. This model reproduces all known states for the tumor. Futherly,we
develop it taking into account periodical immunotheraphy treatment with
cytokines alone. A detailed analysis for the evolution of tumor cells as a
function of frecuency and theraphy burden applied for the periodical treatment
is carried out. Certain threshold values for the frecuency and applied doses
are derived from this analysis. So it seems possible to control and reduce the
growth of the tumor. Also, constant values for cytokines doses seems to be a
succesful treatment.Comment: 6 pages, 7 figure
Approaches based on LAMDA control applied to regulate HVAC systems for buildings
The control of HVAC (Heating Ventilation and Air Conditioning) systems is usually complex because its modeling in certain cases is difficult, since these systems have a large number of components. Heat exchangers, chillers, valves, sensors, and actuators, increase the non-linear characteristics of the complete model, so it is necessary to propose new control strategies that can handle the uncertainty generated by all these elements working together. On the other hand, artificial intelligence is a powerful tool that allows improving the performance of control systems with inexact models and uncertainties. This paper presents new control alternatives for HVAC systems based on LAMDA (Learning Algorithm for Multivariable Data Analysis). This algorithm has been used in the field of machine learning, however, we have taken advantage of its learning characteristics to propose different types of intelligent controllers to improve the performance of the overall control system in tasks of regulation and reference change. In order to perform a comparative analysis in the context of HVAC systems, conventional methods such as PID and Fuzzy-PID are compared with LAMDA-PID, LAMDA-Sliding Mode Control based on Z-numbers (ZLSMC), and Adaptive LAMDA. Specifically, two HVAC systems are implemented by simulations to evaluate the proposals: an MIMO (Multiple-input Multiple-output) HVAC system and an HVAC system with dead time, which are used to compare the results qualitatively and quantitatively. The results show that ZLSMC is the most robust controller, which efficiently controls HVAC systems in cases of reference changes and the presence of disturbances.European CommissionAgencia Estatal de InvestigaciónJunta de Comunidades de Castilla-La Manch
Cosmological simulations using a static scalar-tensor theory
We present CDM -body cosmological simulations in the framework of
a static general scalar-tensor theory of gravity. Due to the influence of the
non-minimally coupled scalar field, the gravitational potential is modified by
a Yukawa type term, yielding a new structure formation dynamics. We present
some preliminary results and, in particular, we compute the density and
velocity profiles of the most massive group.Comment: 4 pages, 6 figures, to appear in Journal of Physics: Conference
Series: VII Mexican School on Gravitation and Mathematical Physics. 26
November to 1 December 2006, Playa del Carmen, Quintana Roo, Mexic
Comprehensive transient-state study for CARMENES-NIR high thermal stability
CARMENES has been proposed as a next-generation instrument for the 3.5m Calar
Alto Telescope. Its objective is finding habitable exoplanets around M dwarfs
through radial velocity measurements (m/s level) in the near-infrared.
Consequently, the NIR spectrograph is highly constraint regarding
thermal/mechanical requirements. As a first approach, the thermal stability has
been limited to \pm 0.01K (within year period) over a working temperature of
243K. This can be achieved by means of several temperature-controlled rooms.
The options considered to minimise the complexity of the thermal design are
here presented, as well as the transient-state thermal analyses realised to
make the best choice
Potential impacts of climate variability on Dengue Hemorrhagic Fever in Honduras, 2010
Climate change and variability are affecting human health and disease direct or indirectly through many mechanisms. Dengue is one of those diseases that is strongly influenced by climate variability; however its study in Central America has been poorly approached. In this study, we assessed potential associations between macroclimatic and microclimatic variation and dengue hemorrhagic fever (DHF) cases in the main
hospital of Honduras during 2010. In this year, 3,353 cases of DHF were reported in the
Hospital Escuela, Tegucigalpa. Climatic periods marked a difference of 158% in the mean incidence of cases, from El Niño weeks (-99% of cases below the mean incidence) to La Niña months (+59% of cases above it) (p<0.01). Linear regression showed significantly higher dengue incidence with lower values of Oceanic Niño Index (p=0.0097), higher rain probability (p=0.0149), accumulated rain (p=0.0443) and higher relative humidity (p=0.0292). At a multiple linear regression model using those variables, ONI values shown to be the most important and significant factor found to be associated with the monthly occurrence of DHF cases (r2=0.649; βstandardized=–0.836; p=0.01). As has been shown herein, climate variability is an important element influencing the dengue epidemiology in
Honduras. However, it is necessary to extend these studies in this and other countries in
the Central America region, because these models can be applied for surveillance as
well as for prediction of dengue
Morphological, molecular and pathogenic characterization of Phytophthora palmivora isolates causing black pod rot of cacao in Colombia
Aim of study: To characterize isolates of Phytophthora sp. causing black pod rot (BPR) of cacao (Theobroma cacao L.).Area of study: Eight cocoa-growing regions in Colombia.Material and methods: Sixty isolates of Phytophthora sp. were obtained from tissues of cacao pods showing symptoms of BPR. Isolates were characterized using the morphology of sporangia and chlamydospores, molecular sequencing of regions of nuclear DNA (rDNA-ITS) and mitochondrial (COX) and virulence in different genotypes of cocoa pods.Main results: A high phenotypic variability between the isolates was determined, being the pedicel length and the length/width ratio (L/W) the most stable characters for species identification. Short pedicels with an average of 3.13 μm ± 0.28 and a length/width ratio of sporangia (L/W) with an average of 1.55 μm ± 0.11 were established as the most consistent morphological characteristics within palmivora species.Research highlights: Phytophthora pamivora was the only species associated to BPR, identified using morphology together with sequence analyses
Physicochemical characteristics and proximate composition of wheat cultivars from the Canary Islands
Proximate composition was determined in 19 wheat cultivars from the Canary Islands in order to establish differences between them and contribute to their characterization. All parameters analysed showed significant differences between cultivars; and also many parameters were affected by the species and subspecies of wheat. Triticum aestivum had higher mean moisture, protein, and fibre and lower mean starch, sucrose, and amylose concentrations than Triticum turgidum. Low starch content and high fibre content could be due to the transformation of starch into resistant starch during desiccation process. An important contribution of complex carbohydrates, including fibre as well as protein and phenolic compounds, was observed for the consumption of wheat
Potential impacts of climate variability on Dengue Hemorrhagic Fever in Honduras, 2010
Climate change and variability are affecting human health and disease direct or indirectly through many mechanisms. Dengue is one of those diseases that is strongly influenced by climate variability; however its study in Central America has been poorly approached. In this study, we assessed potential associations between macroclimatic and microclimatic variation and dengue hemorrhagic fever (DHF) cases in the main
hospital of Honduras during 2010. In this year, 3,353 cases of DHF were reported in the
Hospital Escuela, Tegucigalpa. Climatic periods marked a difference of 158% in the mean incidence of cases, from El Niño weeks (-99% of cases below the mean incidence) to La Niña months (+59% of cases above it) (p<0.01). Linear regression showed significantly higher dengue incidence with lower values of Oceanic Niño Index (p=0.0097), higher rain probability (p=0.0149), accumulated rain (p=0.0443) and higher relative humidity (p=0.0292). At a multiple linear regression model using those variables, ONI values shown to be the most important and significant factor found to be associated with the monthly occurrence of DHF cases (r2=0.649; βstandardized=–0.836; p=0.01). As has been shown herein, climate variability is an important element influencing the dengue epidemiology in
Honduras. However, it is necessary to extend these studies in this and other countries in
the Central America region, because these models can be applied for surveillance as
well as for prediction of dengue
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