This document discusses the potential use of magnetic sails (mag sails) to decelerate interstellar spacecraft. It analyzes two vehicle configurations - a pure fusion rocket and a hybrid rocket with a mag sail second stage. The mag sail could reduce the required fuel by decelerating the vehicle from cruise speed to 1500 km/s before the final deceleration via fusion. Analysis shows the hybrid design could meet the 100-year mission to Alpha Centauri with an initial mass of 12,300 tonnes, significantly less than the 28,600 tonnes required for a pure fusion vehicle. Further research is needed to determine how to protect large mag sail structures from dust in the interstellar medium.
The Optimization of the Generalized Coplanar Impulsive Maneuvers (Two Impulse...paperpublications3
Abstract: The orbit transfer problems using impulsive thrusters have attracted researchers for a long time [3]. One of the objectives in these problems is to find the optimal fuel orbit transfer between two orbits, generally inclined eccentric orbits. The optimal two-impulse orbit transfer problem poses multiple local optima, and classical optimization methods find only local optimum solution. McCue [7] solved the problem of optimal two-impulse orbit transfer using a combination between numerical search and steepest descent optimization procedures. The transfer of satellites in too high orbits as geosynchronous one (geostationary), usually is achieved firstly by launching the satellite in Low Earth Orbit (LEO) (Parking orbit), then in elliptical transfer orbit and finally to the final orbit (Working orbit). The three steps process is known as Hohmann transfer. The Hohmann transfer which involves two circular orbits with different orbital inclinations is known as non‐coplanar Hohmann transfer. If both orbital planes are aligned the Hohmann transfer is known as coplanar what is further considered in this paper. In terms of propellant consumptions the Hohmann transfer is the best known transfer to be applied when transferring between elliptical coplanar orbits. For transfer between elliptical coplanar orbits, the given information usually consists of the altitude of perigee and apogee of the initial and the altitude of perigee and apogee of the final orbits. The velocity to be applied into two orbit points in order to attain the dedicated final orbit is analyzed.
The aim of this paper is compare between three types of coplanar impulsive transfer (two impulses, three impulses and one tangent burn) and conclude about the velocity changes for these types under relation between initial low Earth altitudes and final orbit. For the relation between initial orbit altitudes and final orbit altitude, the velocities to be applied in process of Hohmann transfer are simulated. From respective simulations, the velocity variations on dependence of this relation are derived. And the time of flight is considered too. The problem of spacecraft orbit transfer with minimum fuel consumption is considered, in terms of testing numerical solutions.
The Optimization of the Generalized Coplanar Impulsive Maneuvers (Two Impulse...paperpublications3
Abstract: The orbit transfer problems using impulsive thrusters have attracted researchers for a long time [3]. One of the objectives in these problems is to find the optimal fuel orbit transfer between two orbits, generally inclined eccentric orbits. The optimal two-impulse orbit transfer problem poses multiple local optima, and classical optimization methods find only local optimum solution. McCue [7] solved the problem of optimal two-impulse orbit transfer using a combination between numerical search and steepest descent optimization procedures. The transfer of satellites in too high orbits as geosynchronous one (geostationary), usually is achieved firstly by launching the satellite in Low Earth Orbit (LEO) (Parking orbit), then in elliptical transfer orbit and finally to the final orbit (Working orbit). The three steps process is known as Hohmann transfer. The Hohmann transfer which involves two circular orbits with different orbital inclinations is known as non‐coplanar Hohmann transfer. If both orbital planes are aligned the Hohmann transfer is known as coplanar what is further considered in this paper. In terms of propellant consumptions the Hohmann transfer is the best known transfer to be applied when transferring between elliptical coplanar orbits. For transfer between elliptical coplanar orbits, the given information usually consists of the altitude of perigee and apogee of the initial and the altitude of perigee and apogee of the final orbits. The velocity to be applied into two orbit points in order to attain the dedicated final orbit is analyzed.
The aim of this paper is compare between three types of coplanar impulsive transfer (two impulses, three impulses and one tangent burn) and conclude about the velocity changes for these types under relation between initial low Earth altitudes and final orbit. For the relation between initial orbit altitudes and final orbit altitude, the velocities to be applied in process of Hohmann transfer are simulated. From respective simulations, the velocity variations on dependence of this relation are derived. And the time of flight is considered too. The problem of spacecraft orbit transfer with minimum fuel consumption is considered, in terms of testing numerical solutions.
Payload Mass Improvements of Supersonic Retropropulsive Flight for Human Clas...Max Fagin
Supersonic retropropulsion (SRP) is the use of retrorockets to decelerate during atmospheric flight while the vehicle is still traveling in the supersonic/hypersonic flight regime. In the context of Mars exploration, subsonic retropropulsion has a robust flight heritage for terminal landing guidance and control, but all supersonic deceleration has, to date, been performed by non-propulsive (i.e. purely aerodynamic) methods, such as aeroshells and parachutes.
Extending the use of retropropulsion from the subsonic to the supersonic regime has been identified as an enabling technology for high mass humans-to-Mars architectures.
However, supersonic retropropulsion still possess significant design and control challenges, stemming mainly from the complex interactions between the hypersonic engine plumes, the oncoming airflow, and the vehicle’s exterior surface. These interactions lead to flow fields that are difficult to model and produce counterintuitive behaviors that are not present in purely propulsive or purely aerodynamic flight.
This study will provide an overview of the work done in the design of SRP systems. Optimal throttle laws for certain trajectories will be derived that leverage aero/propulsive effects to decrease propellant requirements and increase total useful landing mass. A study of the mass savings will be made for a 10 mT reference vehicle based on a propulsive version of the Orion capsule, followed by the 100 mT ellipsoid vehicle assumed by NASA’s Mars Design Reference Architecture.
Uma equipe de astrônomos norte-americanos descobriu o par de buracos negros supermassivos mais próximos até agora no universo.
O par de buracos negros está localizado no centro do quasar chamado de PKS 1302-102, a aproximadamente 3.5 bilhões de anos-luz de distância.
Esses dois buracos negros estão separados de apenas uma semana-luz e estão num movimento espiral um em direção ao outro que deve acabar com uma colisão cataclísmica.
Em contraste, o par de buracos negros mais próximos descoberto até então estava separado de aproximadamente 20 anos-luz.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Optimal Control for Torpedo Motion based on Fuzzy-PSO Advantage TechnicalTELKOMNIKA JOURNAL
The torpedo is a nonlinear object which is very difficult to control. Via to manage the rudder angle yaw, the diving plane angle, and the fin shake reduction, the torpedo yaw horizontal, the depth vertical and roll damping of the system are controlled accurately and steadily. In this paper, the particle swarm optimization is used to correct the imprecision of architecture fuzzy parameters. The coverage width of membership function and the overlap degree influence of neighboring membership functions are considered in the method to adjust dynamically from the system errors. Thereby optimizing the control signal and enhancing the torpedo motion quality. The proposed method results in a better performance compared to the other control method such as adaptive fuzzy-neural that proved effective of the proposed controller.
Calibrating a CFD canopy model with the EC1 vertical profiles of mean wind sp...Stephane Meteodyn
For some projects, applying the basic rules of EC1 is not sufficient, and it is required to get a more accurate estimation of the wind speed on the construction site. This can be done by using computational fluid dynamics codes which have the advantage, both to take into account of the terrain inhomogeneity and to calculate 3D orographic effects. In this way, the orography and roughness effects are coupled as they are in the real world. However, applying CFD computations must be in coherence with EC1 code. Then it is necessary to calibrate the ground friction for low roughness terrains as well as the drag force and turbulence production in case of high roughness lengths due to the presence of a canopy (forests or built areas). That is the condition for such methods to be commonly used and agreed by Building Control Officers. In this mind, TopoWind has been developed especially for wind design applications and can be a very useful, practical and objective tool for wind design engineers. The canopy model implemented in TopoWind has been calibrated in order to get the mean wind and turbulence profiles as defined in the EC1 for standard terrains. In this way, TopoWind computations satisfy the continuity between the EC1 values for homogeneous terrains and the more complex cases involving inhomogeneous roughness or orographic effects
Artigo que descreve o trabalho feito com o Chandra nos aglomerados de galáxias de Perseus e Virgo sobre a descoberta de uma turbulência cósmica que impede a formação de novas estrelas.
Optimal trajectory to Saturn in ion-thruster powered spacecraftKristopherKerames
In this document, I derive the equations of motion for an ion-thruster powered spacecraft and use numerical methods to calculate its optimal trajectory to Saturn. I did this work within 48 hours for the University Physics Competition in 2020.
A kiloparsec scale_internal_shock_collision_in_the_jet_of_a_nearby_radio_galaxySérgio Sacani
Pesquisa feita com dados do Hubble mostram ondas de choque em colisão dentro dos chamados jatos extragalácticos emitidos pelos buracos negros supermassivos.
Payload Mass Improvements of Supersonic Retropropulsive Flight for Human Clas...Max Fagin
Supersonic retropropulsion (SRP) is the use of retrorockets to decelerate during atmospheric flight while the vehicle is still traveling in the supersonic/hypersonic flight regime. In the context of Mars exploration, subsonic retropropulsion has a robust flight heritage for terminal landing guidance and control, but all supersonic deceleration has, to date, been performed by non-propulsive (i.e. purely aerodynamic) methods, such as aeroshells and parachutes.
Extending the use of retropropulsion from the subsonic to the supersonic regime has been identified as an enabling technology for high mass humans-to-Mars architectures.
However, supersonic retropropulsion still possess significant design and control challenges, stemming mainly from the complex interactions between the hypersonic engine plumes, the oncoming airflow, and the vehicle’s exterior surface. These interactions lead to flow fields that are difficult to model and produce counterintuitive behaviors that are not present in purely propulsive or purely aerodynamic flight.
This study will provide an overview of the work done in the design of SRP systems. Optimal throttle laws for certain trajectories will be derived that leverage aero/propulsive effects to decrease propellant requirements and increase total useful landing mass. A study of the mass savings will be made for a 10 mT reference vehicle based on a propulsive version of the Orion capsule, followed by the 100 mT ellipsoid vehicle assumed by NASA’s Mars Design Reference Architecture.
Uma equipe de astrônomos norte-americanos descobriu o par de buracos negros supermassivos mais próximos até agora no universo.
O par de buracos negros está localizado no centro do quasar chamado de PKS 1302-102, a aproximadamente 3.5 bilhões de anos-luz de distância.
Esses dois buracos negros estão separados de apenas uma semana-luz e estão num movimento espiral um em direção ao outro que deve acabar com uma colisão cataclísmica.
Em contraste, o par de buracos negros mais próximos descoberto até então estava separado de aproximadamente 20 anos-luz.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Optimal Control for Torpedo Motion based on Fuzzy-PSO Advantage TechnicalTELKOMNIKA JOURNAL
The torpedo is a nonlinear object which is very difficult to control. Via to manage the rudder angle yaw, the diving plane angle, and the fin shake reduction, the torpedo yaw horizontal, the depth vertical and roll damping of the system are controlled accurately and steadily. In this paper, the particle swarm optimization is used to correct the imprecision of architecture fuzzy parameters. The coverage width of membership function and the overlap degree influence of neighboring membership functions are considered in the method to adjust dynamically from the system errors. Thereby optimizing the control signal and enhancing the torpedo motion quality. The proposed method results in a better performance compared to the other control method such as adaptive fuzzy-neural that proved effective of the proposed controller.
Calibrating a CFD canopy model with the EC1 vertical profiles of mean wind sp...Stephane Meteodyn
For some projects, applying the basic rules of EC1 is not sufficient, and it is required to get a more accurate estimation of the wind speed on the construction site. This can be done by using computational fluid dynamics codes which have the advantage, both to take into account of the terrain inhomogeneity and to calculate 3D orographic effects. In this way, the orography and roughness effects are coupled as they are in the real world. However, applying CFD computations must be in coherence with EC1 code. Then it is necessary to calibrate the ground friction for low roughness terrains as well as the drag force and turbulence production in case of high roughness lengths due to the presence of a canopy (forests or built areas). That is the condition for such methods to be commonly used and agreed by Building Control Officers. In this mind, TopoWind has been developed especially for wind design applications and can be a very useful, practical and objective tool for wind design engineers. The canopy model implemented in TopoWind has been calibrated in order to get the mean wind and turbulence profiles as defined in the EC1 for standard terrains. In this way, TopoWind computations satisfy the continuity between the EC1 values for homogeneous terrains and the more complex cases involving inhomogeneous roughness or orographic effects
Artigo que descreve o trabalho feito com o Chandra nos aglomerados de galáxias de Perseus e Virgo sobre a descoberta de uma turbulência cósmica que impede a formação de novas estrelas.
Optimal trajectory to Saturn in ion-thruster powered spacecraftKristopherKerames
In this document, I derive the equations of motion for an ion-thruster powered spacecraft and use numerical methods to calculate its optimal trajectory to Saturn. I did this work within 48 hours for the University Physics Competition in 2020.
A kiloparsec scale_internal_shock_collision_in_the_jet_of_a_nearby_radio_galaxySérgio Sacani
Pesquisa feita com dados do Hubble mostram ondas de choque em colisão dentro dos chamados jatos extragalácticos emitidos pelos buracos negros supermassivos.
"NEWS: Finally the work of Fran De Aquino (on anti-gravity) gets its well-deserved international recognition. Recently he received an offer worth $600,000 from the United States Energy Department to continue his experiments with this department.
We have solid proof for the possibility to shield gravity and it comes from a guaranteed reliable source. The inventor of this technology is the physicist Fran De Aquino, who works at the Maranhao State University in Brazil and has been searching for the secret of anti-gravity for about 25 years. He now seems to have found the best and simplest solution that is easily reproducible and promising for many areas of everyday life.
The first successful experiment took place on 27th January 2000, in the physics department of the Maranhao State University in Brazil. The theoretical basis was published by Fran De Aquino under the name "Gravitation and Electromagnetism: Correlation and Grand Unification".
Now you can enjoy a journey into the land of featherlight aircraft and superluminal speeds, which from now on is no longer a fantasy." ―Graviflight, 2000s
de Aquino's patent: BRPI0805046A2 - "Gravity Control Cell"
“It’s a gravity motor. I have been successful in my research and have built a machine that creates more energy than it uses.” Carr explained he uses a simple storage battery' as the activator, and the machine is operated electrically. Discussing the UFOs, Carr noted “the point is, it is possible to power a craft magnetically and electrically. Levitation of such a craft is strictly a matter of electrical principle,” he said. The earth’s electrical charge is negative, and the atmosphere’s is positive, he said. “To levitate - go up - the object must have the same polarity as the ground.” Carr illustrated this by saying two magnets which are negative will rcpell each other, whereas a negative and a positive magnet will draw toward each other. “I don’t say the (UFO) craft are from somewhere else. I have proved in laboratory experiments that you can levitate a solid body electrically,” Carr said. In his own laboratory “I have been able to levitate aluminum objects”... ―UFOs Man-Made, Otis Carr Believes by Katherine Hatch
"Quartz Crystals Charged by High Frequency Currents Lose Their Weight" - The discovery was made about six weeks ago in a newly established central laboratory of the Nessartsaddin-Werke in Darredein, Poland, by Dr. Kowsky and Engineer Frost. ―Gravity Nullified, Science and Invention for September, 1927
Ultrafast transfer of low-mass payloads to Mars and beyond using aerographite...Sérgio Sacani
With interstellar mission concepts now being under study by various space agencies and institutions,
a feasible and worthy interstellar precursor mission concept will be key to the success of the long
shot. Here we investigate interstellar-bound trajectories of solar sails made of the ultra lightweight
material aerographite. Due to its extremely low density (0.18 kgm−3) and high absorptivity (∼1), a
thin shell can pick up an enormous acceleration from the solar irradiation. Payloads of up to 1 kg can
be transported rapidly throughout the solar system, e.g. to Mars and beyond. Our simulations consider
various launch scenarios from a polar orbit around Earth including directly outbound launches as well
as Sun diver launches towards the Sun with subsequent outward acceleration. We use the poliastro
Python library for astrodynamic calculations. For a spacecraft with a total mass of 1 kg (including
720 g aerographite) and a cross-sectional area of 104 m2, corresponding to a shell with a radius of 56m,
we calculate the positions, velocities, and accelerations based on the combination of gravitational and
radiation forces on the sail. We find that the direct outward transfer to Mars near opposition to Earth
results in a relative velocity of 65 kms−1 with a minimum required transfer time of 26 d. Using an
inward transfer with solar sail deployment at 0.6AU from the Sun, the sail’s velocity relative to Mars
is 118 kms−1 with a transfer time of 126 d, whereMars is required to be in one of the nodes of the two
orbital planes upon sail arrival. Transfer times and relative velocities can vary substantially depending
on the constellation between Earth andMars and the requirements on the injection trajectory to the Sun
diving orbit. The direct interstellar trajectory has a final velocity of 109 kms−1. Assuming a distance
to the heliopause of 120AU, the spacecraft reaches interstellar space after 5.3 yr. When using an
initial Sun dive to 0.6AU instead, the solar sail obtains an escape velocity of 148 kms−1 from the
solar system with a transfer time of 4.2 yr to the heliopause. Values may differ depending on the
rapidity of the Sun dive and the minimum distance to the Sun. The mission concepts presented in this
paper are extensions of the 0.5 kg tip mass and 196m2 design of the successful IKAROS mission to
Venus towards an interstellar solar sail mission. They allow fast flybys atMars and into the deep solar
system. For delivery (rather than fly-by) missions of a sub-kg payload the biggest obstacle remains in
the deceleration upon arrival.
Towards the identification of the primary particle nature by the radiodetecti...Ahmed Ammar Rebai PhD
Radio signal from extensive air showers EAS studied by the CODALEMA experiment have been detected by means of the classic short fat antennas array working in a slave trigger mode by a particle scintillator array. It is shown that the radio shower wavefront is curved with respect to the plane wavefront hypothesis. Then a new tting model (parabolic model) is proposed to fit the radio signal time delay distributions in an event-by-event basis. This model take
into account this wavefront property and several shower geometry parameters such as: the existence of an apparent localised radio-emission source located at a distance Rc from the antenna array of and the radio shower core on the
ground. Comparison of the outputs from this model and other reconstruction models used in the same experiment show:
1)- That the radio shower core is shifted from the particle shower core in a statistic analysis approach.
2)- The capability of the radiodetection method to reconstruct the curvature radius with a statistical error less than 50 g.cm−2 .
Finally a preliminary study of the primary particle nature has been performed based on a comparison between data and Xmax distribution from Aires Monte-Carlo simulations for the same set of events.
The local nanohertz gravitational-wave landscape from supermassive black hole...Sérgio Sacani
Supermassive black hole binary systems form in galaxy mergers and reside in galactic nuclei with large and poorly constrained
concentrations of gas and stars. These systems emit nanohertz gravitational waves that will be detectable by pulsar timing
arrays. Here we estimate the properties of the local nanohertz gravitational-wave landscape that includes individual supermassive
black hole binaries emitting continuous gravitational waves and the gravitational-wave background that they generate.
Using the 2 Micron All-Sky Survey, together with galaxy merger rates from the Illustris simulation project, we find that there are
on average 91 ± 7 continuous nanohertz gravitational-wave sources, and 7 ± 2 binaries that will never merge, within 225 Mpc.
These local unresolved gravitational-wave sources can generate a departure from an isotropic gravitational-wave background at
a level of about 20 per cent, and if the cosmic gravitational-wave background can be successfully isolated, gravitational waves
from at least one local supermassive black hole binary could be detected in 10 years with pulsar timing arrays.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Dr. Sean Tan, Head of Data Science, Changi Airport Group
Discover how Changi Airport Group (CAG) leverages graph technologies and generative AI to revolutionize their search capabilities. This session delves into the unique search needs of CAG’s diverse passengers and customers, showcasing how graph data structures enhance the accuracy and relevance of AI-generated search results, mitigating the risk of “hallucinations” and improving the overall customer journey.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
zkStudyClub - Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex ProofsAlex Pruden
This paper presents Reef, a system for generating publicly verifiable succinct non-interactive zero-knowledge proofs that a committed document matches or does not match a regular expression. We describe applications such as proving the strength of passwords, the provenance of email despite redactions, the validity of oblivious DNS queries, and the existence of mutations in DNA. Reef supports the Perl Compatible Regular Expression syntax, including wildcards, alternation, ranges, capture groups, Kleene star, negations, and lookarounds. Reef introduces a new type of automata, Skipping Alternating Finite Automata (SAFA), that skips irrelevant parts of a document when producing proofs without undermining soundness, and instantiates SAFA with a lookup argument. Our experimental evaluation confirms that Reef can generate proofs for documents with 32M characters; the proofs are small and cheap to verify (under a second).
Paper: https://eprint.iacr.org/2023/1886
Why You Should Replace Windows 11 with Nitrux Linux 3.5.0 for enhanced perfor...SOFTTECHHUB
The choice of an operating system plays a pivotal role in shaping our computing experience. For decades, Microsoft's Windows has dominated the market, offering a familiar and widely adopted platform for personal and professional use. However, as technological advancements continue to push the boundaries of innovation, alternative operating systems have emerged, challenging the status quo and offering users a fresh perspective on computing.
One such alternative that has garnered significant attention and acclaim is Nitrux Linux 3.5.0, a sleek, powerful, and user-friendly Linux distribution that promises to redefine the way we interact with our devices. With its focus on performance, security, and customization, Nitrux Linux presents a compelling case for those seeking to break free from the constraints of proprietary software and embrace the freedom and flexibility of open-source computing.
Generative AI Deep Dive: Advancing from Proof of Concept to ProductionAggregage
Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
A tale of scale & speed: How the US Navy is enabling software delivery from l...sonjaschweigert1
Rapid and secure feature delivery is a goal across every application team and every branch of the DoD. The Navy’s DevSecOps platform, Party Barge, has achieved:
- Reduction in onboarding time from 5 weeks to 1 day
- Improved developer experience and productivity through actionable findings and reduction of false positives
- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Goodbye Windows 11: Make Way for Nitrux Linux 3.5.0!SOFTTECHHUB
As the digital landscape continually evolves, operating systems play a critical role in shaping user experiences and productivity. The launch of Nitrux Linux 3.5.0 marks a significant milestone, offering a robust alternative to traditional systems such as Windows 11. This article delves into the essence of Nitrux Linux 3.5.0, exploring its unique features, advantages, and how it stands as a compelling choice for both casual users and tech enthusiasts.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Climate Impact of Software Testing at Nordic Testing DaysKari Kakkonen
My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...
Magnetic sail braking vs two-stage fusion rockets
1. 1 Introduction
The minimum mission requirement for “Project Icarus” is to receive first data
from Alpha Centauri in 100 years. For maximum data-return the probe needs
to decelerate into orbit around the target star from interstellar transit speeds –
at a minimum the vehicle needs to undergo a total velocity change of 0.09c
(27,000 km/s.) The most conservative approach to achieve this is to use fusion
thrust for the whole velocity change, but this increases the required fuel
considerably, even using a two-stage rocket, as assumed in this paper.
Magnetic-Sails, or Mag-Sails, are a non-propellant means of reducing the
vehicle’s speed from its cruise speed to something closer to orbital velocity, via
creating drag against the thin gas between the stars known as the Interstellar
Medium (ISM) [Ref 1-5].
For the purposes of this paper two vehicle configurations will be studied – the
Pure Fusion and the Hybrid. The 1st Stage will be assumed to accelerate both
kinds of vehicles to cruise speed, while the 2nd Stage will perform either full
deceleration under fusion thrust, in the Pure Fusion case, or deploy a
magnetic-sail, in the Hybrid case, to decelerate to a lower speed, then use
fusion-thrust for deceleration to orbital speeds in the star-system from 1500
km/s (0.005c), at which speed the magnetic-sail becomes increasingly
inefficient as a brake. Matloff [6] has explored the possibility of braking in the
destination star’s astrosphere – the region dominated by its stellar wind – but
this may require determining the size and density of the astrosphere via as yet
undeveloped remote means before a starship can successfully brake within it,
thus it’s an option left for future studies.
2. 2 Magnetic Sails: A Primer
Figure 1: Magnetosphere (from Janhunen [5])
A Magnetic-Sail, or Mag-Sail, for interplanetary or interstellar travel is an
example of drag (or lift) creation via generating an artificial magnetosphere
and interacting with the in-space medium. A Magnetosphere is created by the
interaction between a near dipolar magnetic-field, such as exist around several
planets in our solar system, and a large plasma flow, such as the Solar Wind
(Figure 1). The interaction between the two creates a structure defined by the
behavior of plasma in that region. The border between free-flowing plasma
and the magnetic field is defined by equilibrium between the plasma flow’s
ram pressure and magnetic pressure of the magnetic field encountered.
2.1 Ram-Pressure
Ram-pressure is defined as
(1)
…where is product of the number density and average particle mass of
the plasma flow and is the relative speed of the plasma flow to the magnetic
field. Ram-pressure of the plasma in the Interstellar Medium (ISM) at the
speeds in question will be much higher than the intrinsic magnetic pressure of
the ISM in the Galactic magnetic field.
3. 2.2 Magnetic Pressure
Magnetic pressure is defined (from Cole [7])...
(2)
The magnetic-field strength, B, can be be found by where is the
Dipole Moment of the magnetic loop generating the field and R is the distance
from the centre. Substituting into (2) we get [Eqn.W.7, Ref. 7]…
(3)
2.3 Radius of Magnetosphere
Equating the ram-pressure, and the magnetic-pressure, lets us find the
radius of the magnetosphere formed…
(4)
This forms the basis for determining performance of magnetic sails, but is an
approximation and only applicable when the assumptions of the
magnetohydrodynamic (MHD) plasma flow are valid [5]. Experiments with
laboratory scale plasma sources and mini-magnetospheres have confirmed
that the approximation is applicable to magnetic-sails [8].
2.4 Mag-Sail Dynamics
At its simplest a Mag-Sail uses a single-loop of current to produce the
magnetic-field to form an artificial magnetosphere as seen in Figure 2.
4. Figure 2: The Magnetic-Sail (from [5])
Dipole Moment for a single loop of conductor is computed as:
(5)
Janhunen et.al. [5] derived the following equation for drag created by an
artificial magnetosphere in a plasma flow:
(6)
where D is the drag, the ram-pressure of the vehicle’s motion against the
interstellar medium, I the current in the loop, and magnetic-sail loop
radius.
The vehicle mass is Mv, thus deceleration of the vehicle is: D/Mv
A useful quantity is the mass of the magnetic-sail, Ms. The minimum cross-
sectional area required of superconductor, As, is computed by the ratio of the
current, I, to the maximum super-current density, Jc. However in actual
application bare superconducting wire will be surrounded by protective
layering, a cooling system and normal conductor to allow “quenching” of the
super-current in case of failure of superconductivity. Thus the engineering
super-current density, Je ,is more appropriate, a fraction of the ideal. The
minimum Mag-Sail mass, Ms is therefore:
5. Ms = 2.π.Rm.(I/ Je)
For a given set of magnetic-sail characteristics, I & Rm , and vehicle mass, the
variables reduce to a Deceleration constant, κ
κ (7)
Substituting in Equation (1) & (6) into Equation (7), and some algebra, allows
the Deceleration constant to be computed as follows:
κ (8)
This allows analysis of the magnetic-sail’s equations of motion. According to
Zubrin [] the following relationship for an interstellar vehicle braking against
the ISM applies, with vehicle speed, V, a function of time:
κ (9)
is the initial velocity and is the time since the start of braking.
Taking the first derivative with respect to time gives acceleration as a function
of time:
κ κ (10)
At t=0, this equates to:
κ (11)
…which allows the Deceleration constant to be expressed as a function of the
initial acceleration, and initial velocity, :
κ (12)
6. Integrating Equation (9) with respect to time allows us to derive the
displacement as:
κ
κ (13)
This can be simplified by substituting equation (11) for κ for
κ to give the displacement in terms of the initial and final
velocities
(14)
The ratio has the dimensions of time and provides the useful variable of
the characteristic time, , of the magnetic-sail’s deceleration. Substituting in,
Equation (13) becomes:
(15)
Total deceleration time, to reach a final velocity, can be computed as:
(16)
3 Two Stage Fusion Rockets
“Project Daedalus” remains the most well-defined interstellar fusion rocket,
and has been chosen as the base-line for comparison. The following
characteristics (from [11] & [12]) are germane to this discussion:
7. Table 1: Daedalus Two-Stage Fusion Rocket
Stage Thrust
(newtons)
Dry Mass*
(kilograms)
Exhaust Velocity
(metres/second)
Mass-Flow Rate
(kilograms/second)
Fuel-Tank
Mass-Fraction*
1 7.54E+6 1.4E+6 1.06E+7 0.72 0.047
2 6.63E+5 9.31E+5 9.21E+6 0.0711 0.053
*computed from data in Ref 11 & 12
A significant fraction of the vehicle dry mass is tied up in the propellant and
propulsion system tankage. Helium-3 at 3 K has a vapor pressure of 81.3 kPa,
so the tanks require their void space (26%) to be filled to maintain constant
pressure else the pellets of frozen deuterium and liquid helium-3 would out-
gas. As the tank is emptied some kind of contracting walls would be required
to maintain constant pressure. The tank walls are titanium, with a safety factor
of 1.33. These, with 117 layers of insulation, add a considerable mass also –
212 tonnes for the 1st
Stage, 28.4 tonnes for the 2nd
. Over 1,700 tonnes of mass
for the first stage, and 156 for the second, are required for the helium-3
pressurization.
This limits the maximum mass-ratio that can be achieved by a single-stage
“Daedalus” class vehicle. For a given fuel-tank mass-fraction, b, then the
required propellant mass, P, to achieve a given mass-ratio, R, can be computed
for a given vehicle mass, Ms, via:
(17)
The numerator implies an upper limit to the mass-ratio of:
(18)
As is approached the propellant mass goes to infinity.
Rocket motion, at constant thrust, is described by the following equations for
the acceleration and deceleration phases (derived from Appendix A, in Orth
[9]):
(19)
(20)
…where is the exhaust velocity, is the time required to expel in exhaust
mass the equivalent of the vehicle’s dry-mass at the mass-flow rate for that
8. stage, R is the mass-ratio. The deceleration stage variables are primed as they
are different for the 2nd
Stage of “Daedalus”.
Using the parameters from Table (1) and Equations (16), (18) & (19) the flight
time can be computed via:
(21)
Where the acceleration and deceleration times, are computed via the
following relation:
(22)
With taking their relevant stage values.
For various cruise velocities the results for travel-time were plotted against the
resulting vehicle total mass in Figure 3:
Figure 3 Time (years) vs Mass (tonnes)
The minimum flight time, 71.58 years, is achieved at a cruise velocity of 0.07c
and an initial mass of 281,181 tonnes. Increasing the trip-time by just 5 years
decreases the initial mass by 66%. For the same mass budget as the original
“Daedalus” star-probe (just over 54,000 tonnes) the flight to Alpha Centauri
takes 81.6 years at a cruise speed of 0.05516c, while the “Project Icarus”
minimum mission requirement of a 95.6 year flight-time, to achieve first data
reception on Earth in 100 years, requires an initial mass of 28,600 tonnes and a
0.04635c cruise speed.
0
20
40
60
80
100
120
140
160
0 500000 1000000 1500000
Time vs Mass
Time vs Mass
9. 4 The Interstellar Medium
The Interstellar Medium (ISM) is a thin mix of mostly hydrogen and helium, in
plasma, atomic and molecular form. About 1% of the ISM is in the form of
heavier elements, called “metals” by astrophysicists, either as gas or very small
dust grains. Some fraction of the ISM is in the form of larger objects, perhaps
comet-size or larger, but so spread-out that it can be ignored for the purposes
of this discussion.
Relevant to the operation of magnetic-sails is the hydrogen/helium plasma/gas
mix. Only the charged component, the plasma (a mix of ions and electrons),
interacts directly with the artificial magnetosphere created by the Mag-Sail.
However, relative to the ISM, the magnetic-field is moving very rapidly, and
this rapid change is potentially sufficient to cause ionization of the electrically
neutral atoms and molecules in the ISM.
According to Crawford’s [10] review of the Local ISM (LISM), the nearby G
cloud might extend all the way to Alpha Centauri, with a gas density of
between 0.1-0.2 atoms/cm3
. Interestingly an astrosphere has been detected
around Alpha Centauri, though its properties are yet to be determined. For the
purposes of this study, a density of 0.1 atoms/ cm3
will be assumed.
On average the particles comprising the ISM mass 2.2 x 10-27
kg (75%
hydrogen, 25% helium, by mass) which, combined with the number density
above, allows the Deceleration constant to be computed for Mag-Sails of a
given super-current and radius.
The astrospheres of the stars, and the Sun’s own heliosphere, also suggest a
possible means of protecting magnetic-sail structures against the hail of hyper-
velocity dust particles. Dust particles become charged by UV photons and
cosmic-rays removing electrons from their surfaces. Sufficiently charged dust is
thus deflected by an astrosphere and prevented from entering the inner Solar
System in the case of the Sun [10]. Possibly the artificial magnetosphere of an
operating magnetic-sail will allow dust to be deflected away.
10. 5 Performance of the Magnetic-Sail Fusion-Rocket
The Mag-Sail equipped “Daedalus” 2nd Stage deploys a magnetic-sail to
decelerate from the cruise speed to 1500 km/s, then use fusion-thrust for
deceleration to orbital speeds in the star-system. A “Daedalus” 2nd
Stage, with
450 tonnes Payload, will need an initial mass of 1097 tonnes to decelerate
from 1500 km/s. The Mag-Sail is assumed to mass 1,000 tonnes, with a size
optimized for a lower maximum magnetic-field strength for the
superconductor (assumed to be of the same density as magnesium diboride,
MgB2 ) and an engineered Deceleration constant, κ , of 2x10-11
s2/3
/m1/3
for the
assumed ISM density of 0.1 atoms/cm3
.
The mass of the “Daedalus” 2nd
Stage has been modelled, with the same
assumed tankage fraction and exhaust velocity used for the two-stage Pure
Fusion vehicle.
Figure 4 summarises the results:
Figure 4: Initial Mass (tonnes) vs Total Trip Time (years)
The minimum is achieved at a cruise speed of 0.08015c, with a total trip-time
of 68.033 years and a mass of 73,700 tonnes. The total trip time drops under
11. 70 years for masses between 43,000 and 126,000 tonnes. The minimum
“Project Icarus” requirement (95.6 years total travel time) is met for an initial
mass of 12,300 tonnes. This is a significant improvement over the 28,600
tonnes of the two-stage pure-fusion case.
Also due to the runaway hyperbolic rise of the propellant mass, as discussed
above, the minimum mission can’t be achieved by a single-stage vehicle based
on “Project Daedalus” vehicle characteristics.
6 Conclusions & Recommendations
Magnetic-Sails/Mag-Sails provide a means for significantly improving the
performance of fusion rockets on missions to nearby stars, possibly eliminating
the need for deceleration fuel to be carried to the destination. Future research
will be required to determine the best means of protecting such large, thin
structures against the dust component of the ISM. In particular the suggested
magnetic deflection of charged ISM dust needs to be modeled in detail.
12. 7 References
[1] Andrews, D.G., Zubrin, R.M., "Magnetic Sails and Interstellar Travel",
JBIS, Vol.43, pp.265-272, 1990.
[2] Zubrin, R.M., Andrews, D.G., "Magnetic Sails and Interplanetary Travel,"
AIAA-89-2441, Journal of Spacecraft and Rockets, Vol.28, pp.197, 1991.
[3] Zubrin, R.M., “Detection of Extraterrestrial Civilizations via the Spectral
Signature of Advanced Interstellar Spacecraft”, Astronomical Society of
the Pacific Conference Series, Volume 74. Progress in the Search for
Extraterrestrial Life. 1993 Bioastronomy Symposium, held in Santa Cruz,
California, August 16-20, 1993. Editor, G. Seth Shostak; Publisher,
Astronomical Society of the Pacific, San Francisco, California, 1995.
[ http://adsabs.harvard.edu/abs/1995ASPC...74..487Z]
[4] Zubrin, R.M., Martin, A., “NIAC Study of the Magnetic Sail”, NIAC Final
Report, NASA Institute of Advanced Concepts, 2000.
[http://www.niac.usra.edu/files/studies/final_report/320Zubrin.pdf]
[5] Toivanen, P. K., Janhunen, P., Koskinen, H. E. J., “Magnetospheric
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ISBN 951-697-594-1, ISSN 0782-6079, 78 p., Finnish Meteorological
Institute, 2004.
[ http://www.space.fmi.fi/~pjanhune/papers/eMPii_final_1.3.pdf]
[6] Matloff, G., “Electromagnetic Starship Deceleration in a Stellar Wind”,
JBIS, Vol.62, pp.66-68, 2009.
[7] Cole, G.H.A., Woolfson, M.M., “Planetary Science: the Science of
Planets Around Stars”, IOP Publishing, Bristol, 2002.
[8] Ueno, K., Ayabe, T., Funaki, I., Horisawa, H.,Yamakawa, H., "Imaging of
Plasma Flow around Magnetoplasma Sail in Laboratory Experiment", J.
Plasma Fusion Res. SERIES, Vol. 8, 2009.[
http://www.jspf.or.jp/JPFRS/PDF/Vol8/jpfrs2009_08-1585.pdf ].
[9] Orth, C.D., “VISTA – A Vehicle for Interplanetary Space Transport
Application Powered by Inertial Confinement Fusion”, Lawrence
Livermore National Laboratory Report No. UCRL-LR-110500, 2003. [
http://dx.doi.org/10.2172/15015945 ]
[10] Crawford, I.A., “Project Icarus: A review of local interstellar
medium properties of relevance for space missions to the nearest
stars”, Acta Astronautica, v. 68, iss. 7-8, p. 691-699., 2011.
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Part I; Theoretical Considerations and Calculations", JBIS, Supplement,
pp.S44-S62, 1978.
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Supplement, pp.S104-S115, 1978.