1,721,441 research outputs found
L'eredità scientifica e morale di Arturo Danusso
No full textIl saggio ripercorre in modo critico l'attività di ricerca dell'ingegnere Arturo Danusso che, a quasi cinquant'anni dalla sua scomparsa, è ancora presente nei testi della letteratura scientifica. La rilevanza internazionale del suo pensiero, sia in relazione agli studi di ingegneria sismica che allo sviluppo di nuove concezioni per le strutture in cemento armato, quali ponti, edifici alti ed interventi di restauro, è ancora oggi estremamente significativa
Penataan karawitan "Komamahito"
No full textPenataan karawitan "Komamahito"
Karya : Sumini Rahardjo, Ujian penyajian Jur. Karawitan ISI Surakart
SUMINI LEDHEK BARANGAN DARI SUKOREJO, KEDUNG JERUK, MOJOGEDANG, KABUPATEN KARANGANYAR
No full textThe object of this research is Sumini, a woman from the village of Sukorejo, in the Kedung Jeruk, sub-district of Mojogedang, in the district of Karanganyar, whose profession is a Ledhek barangan artist. The research aims to discover Sumini’s journey to become a Ledhek barangan artist and her style of movements when performing, or “mbarang Ledhek”. It is a qualitative research study which uses a choreographic approach. In order to analyze Sumini’s journey to become a Ledhek barangan artist, T. Inrahim Alfian’s theory of history is used. In order to analyze Sumini’s style of movements, the writer uses Desmond Morris’s theory, as quoted and presented by Soedarsono. Due to her skill and perseverance, Sumini has managed to create a unique style of
movement in her performance of Ledhek barangan, such as movements that are performed with a large volume and a technique in which the left foot is positioned on tiptoe(gejuk)behind the right foot.
Keywords: Ledhek barangan, Sumber Laras, Sumini
Monte Carlo analysis of dosimetric issues in space exploration
No full textThe Radiation protection is of paramount importance in the planning of human exploration activities in space. The related risks must be considered with respect to two aspects: devising a proper shielding and providing answers to the requirement of an effective dosimetry evaluation in astronaut’s activities. Both aspects have been considered using the Monte Carlo (MC) code MCNP 6.2 as the reference tool. As case study an application devised for the National Aeronautics and Space Administration (NASA) Artemis program has been chosen. The project aims to establish a sustainable human presence on the Moon, envisioning the realization of an outpost that will serve as a steppingstone for space exploration endeavors. A Class III shelter, in situ resource utilization (ISRU) built habitat for the Moon, has been designed through computational methods and topology optimization techniques, and analyzed in terms of radiation shielding performances and the strictly related structural behavior. The outpost must be able to withstand temperature variations, micrometeorite impacts, and the absence of a substantial atmosphere. Any solution studied to respect the constraints must devise robust and innovative materials and techniques to create habitats that have as goal the shielding from the Galactic Cosmic Rays (GCR) and from the solar flares to provide a safe and habitable environment at the time scales scheduled for the missions. Moreover, the outpost design must incorporate strategies for extracting and utilizing local re- sources. Overcoming such challenges will pave the way for the establishment of a sustainable human presence on the Moon and serve as a crucial leap for future space exploration missions
Monte Carlo Analysis of dosimetric issues in space exploration
No full textIntroduction
The radiation protection is of paramount importance in the planning of human exploration activities in space.
The related risks must be considered with respect two aspects: devising a proper shielding and answer to the requirement of an effective dosimetry evaluation during astronaut activities.
Both aspects have been considered using as reference tool the Monte Carlo code MCNP 6.2. As case study a possible application to the NASA Artemis program has been chosen.
The project aims to establish a sustainable human presence on the Moon, envisioning the realization of an outpost that will serve as a steppingstone for space exploration endeavors.
Methods
A Class III shelter, ISRU derived habitat with local resources available on the Moon, has been designed through computational methods and topology optimization techniques, and analyzed in terms of radiation shielding performances and structural behavior.
Results
The outpost must be able to withstand temperature variations, micrometeorite impacts, and the absence of a substantial atmosphere.
Any solution studied to respect the constraints must devise robust and innovative materials and techniques to create habitats that have as goal the shielding from the Galactic Cosmic Rays and from the solar flares to provide a safe and habitable environment at the time scales scheduled for the mission.
Resource utilization is crucial for sustaining long-duration missions on the Moon as envisaged in the ARTEMIS program.
This implies the outpost design must incorporate strategies for extracting and utilizing local resources.
Conclusions
The design of a lunar outpost for the NASA Artemis program is a complex undertaking that involves addressing challenges related to lunar environment, resource utilization, power generation, logistics, and crew well-being.
Overcoming such challenges will pave the way for the establishment of a sustainable human presence on the Moon and serve as a crucial leap for future space exploration missions
Studio di macchine Plasma Focus destinate alla produzione di radioisotopi per diagnostica PET e di fasci di radiazioni per terapia oncologica
No full textIl Plasma Focus (PF) è un dispositivo in grado di generare, accelerare, comprimere e confinare in una ridotta regione di spazio un gas ionizzato allo stato di plasma. Tale plasma può essere portato in condizioni di densità e temperatura sufficienti ad innescare reazioni di fusione nucleare con processi analoghi a quelli che si verificano nelle stelle. A tali reazioni consegue produzione di isotopi differenti al variare del tipo e della quantità (in genere pochi centesimi di mole) di gas immessi in una opportuna camera da vuoto. In funzione del tipo di reazione e’ poi tecnicamente possibile produrre oltre agli isotopi fasci di particelle e radiazioni. I processi coinvolti avvengono per mezzo della scarica ripetuta di un banco di condensatori a tensione relativamente alta (qualche decina di kV); tali scariche hanno durata temporale dell’ordine di alcune diecine di microsecondi; all’interno di tale intervallo temporale la produzione di isotopi e dei fasci di particelle annessi avviene in poche decine di nanosecondi. Tale comportamento dinamico fa sì che i fenomeni di produzione siano totalmente controllabili e sicuri in analogia con i tubi a raggi X e gli acceleratori oggi in uso.
Tipologie di produzione:
- reazioni termonucleari utili alla produzione diretta di radioisotopi a breve vita media;
- neutroni veloci
- fasci di elettroni relativistici
- raggi X a bassa energia.
Tipologie di applicazioni biomediche immediate:
- produzione endogena di radioisotopi in forma gassosa per PET e, ad esempio 18F dalla reazione O16(He3,p)F18, e 15O dalla reazione N14(d,n)O15;
- produzione di neutroni epitermici (<10-20 KeV) mediante rallentamento dei neutroni prodotti dalla reazione di fusione deuterio-trizio per utilizzo in BNCT (Boron Neutron Capture Therapy) per radioterapia di tumori cerebrali profondi;
- produzione di neutroni termici per successiva termalizzazione per terapia col boro (BNCT) di tumori diffusi tramite autotrapianto (espianto, irraggiamento, reimpianto);
- radioterapia interstiziale ed intraoperatoria per piccole masse tumorali (dimensione tipica inferiore al centimetro) tramite irraggiamento fotonico a bassa energia e ad altissimo dose-rate prodotto per ogni scarica della macchina dagli impulsi di elettroni relativistici (con energia inferiore a 1 MeV) retroemessi; la particolare tipologia del fascio consentirebbe anche di operare con tecniche ecoguidate
Shape, Structure and Material Compliance with Radiation Protection Requirements for Extraplanetary Modules
No full textThis research aims to explore a design solution for an innovative extraplanetary module that combines architectural design, structure and radiation protection for sustaining human life on Mars.
The WATER (Water shielded Architectural Tree for Extraplanetary Resiliency) module is designed in order to increment the use of local resources (In Situ Resources Utilization) and robotic fabrication techniques for remote construction before human arrival on Mars.
The key element of the design is the water that can be extracted from the substrate of the Martian regolith. Water plays an essential role in both in supporting life and protecting humans inside the habitat. Because of the reduced gravity and the fine atmosphere, the major load that a structure has to withstand on Mars is the internal pressurization. To balance that load and have a more efficient foundation system, the structure needs to be covered by a thick layer of water that is also extremely important for shielding against the harmful cosmic radiation.
In fact, it is well known that a major threat to extraplanetary exploration is given by high energy cosmic particles and gamma fluxes. This work deals with the radiation protection constraints that should be considered for the WATER module, designed as an optimized possible long term habitat for Mars. The main materials considered for the module are the Martian regolith and, with respect to radiation shielding, the water that will be driven to fill the layer between the external and internal surfaces that will sustain the exposed external structures.
The simulations, carried out with a standard Monte Carlo code like MCNPX and MCNP6, that is able to directly analyze the mesh geometries coming from the WATER module structural Finite Element model, define the optimal conditions in terms of shielding thickness and layer’s material composition.
As output of the analysis, expositions and doses, that the inhabitants of these future architecture should bear, have been obtained.
The final shielding configuration is integrated in the Finite Element model of the project for the structural analysis. The results prove that the water content, subjected to the Martian gravity, helps reducing the tensile stresses inside the structure due to the internal pressurization
GENII-LIN
No full textThe aim of the GENII-LIN project was to develop an
open source multipurpose health physics code running on
Linux platform, for calculating radiation dose and risk
from radionuclides released to the environment. The
general features of the GENII-LIN system include
[1] capabilities for calculating radiation dose both for
acute and chronic releases, with options for annual
dose, committed dose and accumulated dose
[2] capabilities for evaluating exposure pathways
including direct exposure via water (swimming, boating,
fishing), soil (buried and surface sources) and air
(semi-infinite cloud and finite cloud model),
inhalation pathways and ingestion pathways.
The release scenarios considered are:
- acute release to air, from ground level or elevated
sources, or to water;
- chronic release to air, from ground level or elevated
sources, or to water;
- initial contamination of soil or surfaces
Computational Design and International Cooperation in Space Architecture Education
Full text linkSpace architecture is an interdisciplinary field that involves many different branches of knowledge, like space science, engineering, architecture, industrial design, medicine, psychology, and art, covering all aspects and needs for human space exploration in LEO and other celestial bodies, like the Moon and Mars. For this reason, the educational effort should involve a set of different skills in the various fields in order to design a safe and livable environment for sustaining human's life in space. Since 2020, the course at Politecnico di Milano “Architecture for Human Space Exploration" for the School of Architecture, Urban Planning, and Construction Engineering is implementing this multi-disciplinarity thanks to external reviewers, that are experts in the Space Architecture domain, and the collaboration, in the actual A.Y. 2021-22, with the Webinar Series at MIT Media Lab “Design Exploration: towards a Moon Architecture". The Webinar Series, open to all MIT and Harvard students, addressed numerous topics and aspects of designing a lunar settlement with several experts about history of space architecture, crewed missions, habitation systems and habitability requirements, In Situ Resources Utilization, Human Factor Design principles, radiation shielding technologies, sustainability of space exploration, and inspirational talks. The talks gathered space architects, engineers and professionals from NASA JPL, NASA JSC and ESA, astronauts, faculty from different universities (University of Houston - SICSA, UW-Madison, Université Paris-Saclay, SDU, University of Bologna, Politecnico di Milano, MIT Media Lab and MIT AeroAstro) and companies (Trotti Studio, Thales Alenia Space, SOM, ICON). Indeed, the students attending this collaborative classroom had to develop a space architecture project for the Moon or Mars. Therefore, the possibility to actively participate to this Webinar Series resulted extremely effective since students applied the acquired knowledge directly to their Space Architecture projects. The approach is different in case of short and deeply focused Workshop on computational design applied to Space Architecture on worldwide educational platforms, like the Workshop “Explore Moon Architecture" for Digital Futures and the Workshop “Mars Architecture" for Parametric Architecture. The educational strategy for these Workshops is based on the development of customized computational design tools for generating form-finding, multi-objective and topology optimization processes for space structures. Students learned how to use Grasshopper, an algorithmic modeling software, and several other plugins, like Octopus©, Ameba©, Karamba3D©, Kangaroo©, Weaverbird© and others. In this paper, some Space Architecture projects resulting from these two educational strategies will be briefly presented and discussed
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