Sistema Terra-Lluna-Sol: fases i eclipsis

Es presenten alguns models sobre les fases de la Lluna i els eclipsis de Sol i de Lluna. També s'utilitzen els eclipsis per determinar distàncies i diàmetres en el sistema Terra-Lluna-Sol. Finalment es presenta una activitat senzilla que permet mesurar longituds i altures sobre la superfície lunar i s'explica l'origen de les marees

A randomized kinodynamic planner for closed-chain robotic systems

Kinodynamic RRT planners are effective tools for finding feasible trajectories in many classes of robotic systems. However, they are hard to apply to systems with closed-kinematic chains, like parallel robots, cooperating arms manipulating an object, or legged robots keeping their feet in contact with the environ- ment. The state space of such systems is an implicitly-defined manifold, which complicates the design of the sampling and steering procedures, and leads to trajectories that drift away from the manifold when standard integration methods are used. To address these issues, this report presents a kinodynamic RRT planner that constructs an atlas of the state space incrementally, and uses this atlas to both generate ran- dom states, and to dynamically steer the system towards such states. The steering method is based on computing linear quadratic regulators from the atlas charts, which greatly increases the planner efficiency in comparison to the standard method that simulates random actions. The atlas also allows the integration of the equations of motion as a differential equation on the state space manifold, which eliminates any drift from such manifold and thus results in accurate trajectories. To the best of our knowledge, this is the first kinodynamic planner that explicitly takes closed kinematic chains into account. We illustrate the performance of the approach in significantly complex tasks, including planar and spatial robots that have to lift or throw a load at a given velocity using torque-limited actuators.Peer ReviewedPreprin

Principal Eigenvalue of Mixed Problem for the Fractional Laplacian: Moving the Boundary Conditions

We analyze the behavior of the eigenvalues of the following non local mixed problem \left\{ \begin{array}{rcll} (-\Delta)^{s} u &=& \lambda_1(D) \ u &\inn\Omega,\\ u&=&0&\inn D,\\ \mathcal{N}_{s}u&=&0&\inn N. \end{array}\right Our goal is to construct different sequences of problems by modifying the configuration of the sets $D$ and $N$, and to provide sufficient and necessary conditions on the size and the location of these sets in order to obtain sequences of eigenvalues that in the limit recover the eigenvalues of the Dirichlet or Neumann problem. We will see that the non locality plays a crucial role here, since the sets $D$ and $N$ can have infinite measure, a phenomenon that does not appear in the local case (see for example \cite{D,D2,CP})

IMPROVED SOUND SPEED CONTROL THROUGH REMOTELY DETECTING STRONG CHANGES IN THE THERMOCLINE

Internal waves are a common phenomenon associated with stratification developed in shallow tidal seas during summer time. From a hydrographic point of view, they result in very rapid undulations in the main velocline which, if not accounted for, will result in significant refraction errors in multibeam echo sounder data. Mechanical sound speed profiling, both static and mobile, cannot sample this structure adequately (Hughes Clarke, 2017). Thus, an alternate means of detecting and accounting for that variability is needed. Within the oceanographic community, it has long been recognized that a distinct acoustic volume scattering layer is often associated within or close to major oceanographic boundaries. This has been noted to reflect a combination of temperature/salinity microstructure and zooplankton around the pycnocline depth. Several weeks of multibeam survey on the Irish continental shelf were undertaken during which multispectral acoustic scattering data from a Simrad EK60 scientific echo sounder were acquired together with profiles from a Moving Vessel Profiler. This thesis proposes and implements a method to determine the evolving sound speed structure by processing the images derived from the EK60 echo sounder. This is done by extracting the scattering layer depth and finding the correlations with the velocline found in each of the discrete MVP profiles. Thus, a continuously evolving estimate of the local sound speed structure is derived. From this, by calculating the associated depth bias in the seafloor modeling caused by the difference in sound speed structure between the last actual profile and the estimate at each ping, a visual indication of the need for a new in situ measurement is made. In this manner, the sound speed structure may be monitored to adjust the spatial and temporal resolutions of the profile casts more efficiently

NASE astronomy courses in South America

Postprint (published version

SUPLEMENTASI TEPUNG DAUN KELOR MENINGKATKAN KADAR HEMOGLOBIN IBU HAMIL ANEMIA MELALUI PEMBERDAYAAN KADER POSYANDU KELURAHAN MANDALA DI WILAYAH PUSKESMAMAS MAMAJANG

ABSTRAK             Anemia pada ibu hamil hingga saat ini masih menjadi salah satu masalah kesehatan masyarakat di Indonesia bahkan di dunia yang dapat berakibat buruk terutama pada kelompok rawan gizi berawal dari ibu hamil, hingga pada bayi, anak balita, anak sekolah, remaja sebagai calon sumberdaya manusia yang pada gilirannya akan berpengaruh terhadap pembangunan Nasional. Masalah tersebut tidak terlepas dari kondisi ekonomi dan daya beli masyarakat yang tidak menentu, diperberat oleh tingkat pendidikan, pengetahuan dan sikap serta perilaku yang kurang mendukung.   Sebuah kearifan lokal, daun kelor salah satu tanaman super food diyakini sebagai sumberhayati yang kaya kandungan gizi dibanding sumber nutrisi lainnya, dan secara farmakologis mengandung zat besi untuk meningkatkan kadar Hb, namun oleh masyarakat pada umumnya dan khususnya masyarakat Kelurahan Mandala menjadikan tumbuhan tersebut sebatas bahan sayuran sebagai warisan turun temurun, namun berbagai kekayaan nilai hayati belum dipahami dalam cara pengolahannya. Kehadiran engabdian masyarakat melalui program Kemitraan Masyarakat menjadi dasar bagi tim PPDM untuk mendekatkan masyarakat dalam proses hilirisasi hasil penelitian guna meningkatkan kesadaran mereka dalam pemanfaatan sumberdaya ekologis melalui peran kader Posyandu dengan metode edukatif dengan tatap muka, diskusi dan simulasi di Wilayah Puskesmas Mamajang. Hasilnya menunjukkan adanya peningkatan pengetahuan dan sikap kader Posyandu tentang manfaat dan pengolahan daun kelor menjadi aneka Cemilan dan mengimplementasikannya di Posyandu, disamping output berupa lembar balik, dan artikel sehingga dapat menjadi referensi bagi masyarakat dan Institusi terkait sebagai bagian dari upaya mengentaskan kasus-kasus anemia gizi yang menimpa masyarakat rawan gizi, khususnya pada wanita hamil, nifas dan menyusui

Widening the perception of engineering within society

In general, our society has no real views on or has an inappropriate idea about what engineering means. Everything related to pollution, bad usage of natural resources and human endeavours is connected to engineering. Modern society accepts the positive achievements that engineering has given us, but some people continue to hold a “negative opinion” related to technology. It is important to show and to explain to the general public that engineering generates many benefits to society. Communication is essential in our society. The Spanish programme “Ciencia en Acción” offers the possibility to link up with a general audience which has a positive approach to science, technology and engineering. This project began ten years ago from a group of scientist and engineers working in CERN, ESA and ESO who promoted a first meeting in Geneva, at CERN headquarters in order to give a message to European society by means of teachers and students. The main objectives of “Ciencia en Acción” are: • Finding new ideas to make science and technology attractive to the population • Pointing out the international character of science and technology • Promoting the interest in science for educators and students • Involving research in scientific and technologic communication activities • Showing the importance of science for progress and welfare in general. Our society continually needs more engineers and more from the engineers. If we want to change mind sets, we need to explain the applications and help the use of engineering to increase the quality of life of everybody in a sustainable manner. If we want to communicate successfully the advantages of engineering we must get close up to our audience. What are the facts that people remember best? Without doubt, the answer is “the facts involving positive emotions”. If we feel a passion related to some aspects of technology, we will remember it and we will add a positive connotation to engineering. This relationship will stay with the person for some time and it will be a cord that will not be broken easily. It is good that the experiences, and in special the first experiences with engineering, are exciting. If a child had a good feeling in the school when “making a device” with other children, he/she will continue with this positive feeling in the future. We must get the students to feel emotive in building simple devices or in solving some problems in the technological framework! School classes should offer some examples of this kind of experiences. We should use all the above mentioned strategies such as causing surprise, enthusiasm, encouraging the participation of everybody and to feel technology much more approach. These strategies can be presented in the “Ciencia en Acción” programme in order to show them to all the educational, scientific and technological communities. “Ciencia en Acción” programme is open to all the Spanish and Portuguese speaking countries and all the participants can present their contributions in any of the official languages in Spain and Portugal. The CSIC (Spanish National Research Council), INTA (National Institute for Aerospace Technology), the RSEF (Spanish Royal Physical Society), the SGE (Spanish Geologist Society) and the UNED (Spanish Open University) have annually organised “Ciencia en Acción” in order to increase the quality of science and technology communication and to promote innovation within science teaching. In the last edition of “Ciencia en Acción”, the Portuguese program “CienciaViva” (Portuguese Science Programme) has been integrated in the organisers group. This program moves Science and Engineering to the street by involving general audiences in both these areas. “Ciencia en Acción” increases in importance every year. The final event of the last edition grouped together about 15,000 people in two days. “Ciencia en Acción” is integrated in the international program “Science on Stage” organised by the EIROforum (the CERN (European Organisation for Nuclear Research), the EFDA (European Fusion Development Agreement), the EMBL (European Molecular Biology Laboratory), the ESA (European Space Agency), the ESO (European Organisation for Astronomical Research in the Southern Hemisphere), the ESRF (European Synchrotron Radiation Facility) and the ILL (Institute Laue-Langevin) with the financial support of the European Union. In the most recent editions of “Ciencia en Acción”, a specific category has been promoted in order to bring the general public closer to “Science, Engineering and Values”. Several proposals were presented within this new category: from university departments, from engineering teams, and from NGOs coming from Spanish and Portuguese speaking countries. This modality is sponsored by a chair linked to the Technical University of Catalonia and the leading electric company ENDESA showing that people involved in the management of public and private entities can reach agreement about the importance of the previously mentioned topics.Peer Reviewe