Control system design for the constellation acquisition phase of the LISA mission

Energy Technology Data Exchange (ETDEWEB)

Cirillo, Francesca; Gath, Peter F, E-mail: francesca.cirillo@astrium.eads.ne, E-mail: peter.gath@astrium.eads.ne [Astrium GmbH Satellites, 88039 Friedrichshafen (Germany)

2009-03-01

The objective of the constellation acquisition phase for the LISA mission is to establish the three laser links between the three spacecraft of the LISA constellation so that the interferometric measurements for the science experiment can commence. The laser beam acquisition for LISA is extremely challenging given the 5 million km distance between the spacecraft, the inherent limits of the attitude sensors accuracy, the orbit determination accuracy issues and the time required to phase-lock the incoming and outgoing laser signals. This paper presents the design of the control system for the acquisition phase of the LISA constellation: the acquisition operational procedure is outlined, guidance laws are defined together with the Gyro Mode attitude control principle, which implements a Kalman filter for disturbances rejection purposes. Constellation-wide non-linear simulations demonstrate that the LISA constellation acquisition phase is feasible by means of the proposed control strategy.

Control system design for the constellation acquisition phase of the LISA mission

International Nuclear Information System (INIS)

Cirillo, Francesca; Gath, Peter F

2009-01-01

The objective of the constellation acquisition phase for the LISA mission is to establish the three laser links between the three spacecraft of the LISA constellation so that the interferometric measurements for the science experiment can commence. The laser beam acquisition for LISA is extremely challenging given the 5 million km distance between the spacecraft, the inherent limits of the attitude sensors accuracy, the orbit determination accuracy issues and the time required to phase-lock the incoming and outgoing laser signals. This paper presents the design of the control system for the acquisition phase of the LISA constellation: the acquisition operational procedure is outlined, guidance laws are defined together with the Gyro Mode attitude control principle, which implements a Kalman filter for disturbances rejection purposes. Constellation-wide non-linear simulations demonstrate that the LISA constellation acquisition phase is feasible by means of the proposed control strategy.

Nuclear risk analysis of the Ulysses mission

International Nuclear Information System (INIS)

Bartram, B.W.; Vaughan, F.R.; Englehart, D.R.W.

1991-01-01

The use of a radioisotope thermoelectric generator fueled with plutonium-238 dioxide on the Space Shuttle-launched Ulysses mission implies some level of risk due to potential accidents. This paper describes the method used to quantify risks in the Ulysses mission Final Safety Analysis Report prepared for the U.S. Department of Energy. The starting point for the analysis described herein is following input of source term probability distributions from the General Electric Company. A Monte Carlo technique is used to develop probability distributions of radiological consequences for a range of accident scenarios thoughout the mission. Factors affecting radiological consequences are identified, the probability distribution of the effect of each factor determined, and the functional relationship among all the factors established. The probability distributions of all the factor effects are then combined using a Monte Carlo technique. The results of the analysis are presented in terms of complementary cumulative distribution functions (CCDF) by mission sub-phase, phase, and the overall mission. The CCDFs show the total probability that consequences (calculated health effects) would be equal to or greater than a given value

Tank waste remediation system mission analysis report

International Nuclear Information System (INIS)

Acree, C.D.

1998-01-01

This document describes and analyzes the technical requirements that the Tank Waste Remediation System (TWRS) must satisfy for the mission. This document further defines the technical requirements that TWRS must satisfy to supply feed to the private contractors' facilities and to store or dispose the immobilized waste following processing in these facilities. This document uses a two phased approach to the analysis to reflect the two-phased nature of the mission

Simulation of Mission Phases

Science.gov (United States)

Carlstrom, Nicholas Mercury

2016-01-01

This position with the Simulation and Graphics Branch (ER7) at Johnson Space Center (JSC) provided an introduction to vehicle hardware, mission planning, and simulation design. ER7 supports engineering analysis and flight crew training by providing high-fidelity, real-time graphical simulations in the Systems Engineering Simulator (SES) lab. The primary project assigned by NASA mentor and SES lab manager, Meghan Daley, was to develop a graphical simulation of the rendezvous, proximity operations, and docking (RPOD) phases of flight. The simulation is to include a generic crew/cargo transportation vehicle and a target object in low-Earth orbit (LEO). Various capsule, winged, and lifting body vehicles as well as historical RPOD methods were evaluated during the project analysis phase. JSC core mission to support the International Space Station (ISS), Commercial Crew Program (CCP), and Human Space Flight (HSF) influenced the project specifications. The simulation is characterized as a 30 meter +V Bar and/or -R Bar approach to the target object's docking station. The ISS was selected as the target object and the international Low Impact Docking System (iLIDS) was selected as the docking mechanism. The location of the target object's docking station corresponds with the RPOD methods identified. The simulation design focuses on Guidance, Navigation, and Control (GNC) system architecture models with station keeping and telemetry data processing capabilities. The optical and inertial sensors, reaction control system thrusters, and the docking mechanism selected were based on CCP vehicle manufacturer's current and proposed technologies. A significant amount of independent study and tutorial completion was required for this project. Multiple primary source materials were accessed using the NASA Technical Report Server (NTRS) and reference textbooks were borrowed from the JSC Main Library and International Space Station Library. The Trick Simulation Environment and User

Crew Transportation System Design Reference Missions

Science.gov (United States)

Mango, Edward J.

2015-01-01

Contains summaries of potential design reference mission goals for systems to transport humans to andfrom low Earth orbit (LEO) for the Commercial Crew Program. The purpose of this document is to describe Design Reference Missions (DRMs) representative of the end-to-end Crew Transportation System (CTS) framework envisioned to successfully execute commercial crew transportation to orbital destinations. The initial CTS architecture will likely be optimized to support NASA crew and NASA-sponsored crew rotation missions to the ISS, but consideration may be given in this design phase to allow for modifications in order to accomplish other commercial missions in the future. With the exception of NASA’s mission to the ISS, the remaining commercial DRMs are notional. Any decision to design or scar the CTS for these additional non-NASA missions is completely up to the Commercial Provider. As NASA’s mission needs evolve over time, this document will be periodically updated to reflect those needs.

Probability of success for phase III after exploratory biomarker analysis in phase II.

Science.gov (United States)

Götte, Heiko; Kirchner, Marietta; Sailer, Martin Oliver

2017-05-01

The probability of success or average power describes the potential of a future trial by weighting the power with a probability distribution of the treatment effect. The treatment effect estimate from a previous trial can be used to define such a distribution. During the development of targeted therapies, it is common practice to look for predictive biomarkers. The consequence is that the trial population for phase III is often selected on the basis of the most extreme result from phase II biomarker subgroup analyses. In such a case, there is a tendency to overestimate the treatment effect. We investigate whether the overestimation of the treatment effect estimate from phase II is transformed into a positive bias for the probability of success for phase III. We simulate a phase II/III development program for targeted therapies. This simulation allows to investigate selection probabilities and allows to compare the estimated with the true probability of success. We consider the estimated probability of success with and without subgroup selection. Depending on the true treatment effects, there is a negative bias without selection because of the weighting by the phase II distribution. In comparison, selection increases the estimated probability of success. Thus, selection does not lead to a bias in probability of success if underestimation due to the phase II distribution and overestimation due to selection cancel each other out. We recommend to perform similar simulations in practice to get the necessary information about the risk and chances associated with such subgroup selection designs. Copyright © 2017 John Wiley & Sons, Ltd.

Printable Spacecraft: Flexible Electronic Platforms for NASA Missions. Phase One

Science.gov (United States)

Short, Kendra (Principal Investigator); Van Buren, David (Principal Investigator)

2012-01-01

Atmospheric confetti. Inchworm crawlers. Blankets of ground penetrating radar. These are some of the unique mission concepts which could be enabled by a printable spacecraft. Printed electronics technology offers enormous potential to transform the way NASA builds spacecraft. A printed spacecraft's low mass, volume and cost offer dramatic potential impacts to many missions. Network missions could increase from a few discrete measurements to tens of thousands of platforms improving areal density and system reliability. Printed platforms could be added to any prime mission as a low-cost, minimum resource secondary payload to augment the science return. For a small fraction of the mass and cost of a traditional lander, a Europa flagship mission might carry experimental printed surface platforms. An Enceladus Explorer could carry feather-light printed platforms to release into volcanic plumes to measure composition and impact energies. The ability to print circuits directly onto a variety of surfaces, opens the possibility of multi-functional structures and membranes such as "smart" solar sails and balloons. The inherent flexibility of a printed platform allows for in-situ re-configurability for aerodynamic control or mobility. Engineering telemetry of wheel/soil interactions are possible with a conformal printed sensor tape fit around a rover wheel. Environmental time history within a sample return canister could be recorded with a printed sensor array that fits flush to the interior of the canister. Phase One of the NIAC task entitled "Printable Spacecraft" investigated the viability of printed electronics technologies for creating multi-functional spacecraft platforms. Mission concepts and architectures that could be enhanced or enabled with this technology were explored. This final report captures the results and conclusions of the Phase One study. First, the report presents the approach taken in conducting the study and a mapping of results against the proposed

Critical early mission design considerations for lunar data systems architecture

Science.gov (United States)

Hei, Donald J., Jr.; Stephens, Elaine

1992-01-01

This paper outlines recent early mission design activites for a lunar data systems architecture. Each major functional element is shown to be strikingly similar when viewed in a common reference system. While this similarity probably deviates with lower levels of decomposition, the sub-functions can always be arranged into similar and dissimilar categories. Similar functions can be implemented as objects - implemented once and reused several times like today's advanced integrated circuits. This approach to mission data systems, applied to other NASA programs, may result in substantial agency implementation and maintenance savings. In today's zero-sum-game budgetary environment, this approach could help to enable a lunar exploration program in the next decade. Several early mission studies leading to such an object-oriented data systems design are recommended.

Tank waste remediation system retrieval and disposal mission key enabling assumptions

International Nuclear Information System (INIS)

Baldwin, J.H.

1998-01-01

An overall systems approach has been applied to develop action plans to support the retrieval and immobilization waste disposal mission. The review concluded that the systems and infrastructure required to support the mission are known. Required systems are either in place or plans have been developed. An analysis of the programmatic, management and technical activities necessary to declare Readiness to Proceed with execution of the mission demonstrates that the system, people, and hardware will be on line and ready to support the private contractors. The systems approach included defining the retrieval and immobilized waste disposal mission requirements and evaluating the readiness of the TWRS contractor to supply waste feed to the private contractors in June 2002. The Phase 1 feed delivery requirements from the Private Contractor Request for Proposals were reviewed, transfer piping routes were mapped on it, existing systems were evaluated, and upgrade requirements were defined. Technical Basis Reviews were completed to define work scope in greater detail, cost estimates and associated year by year financial analyses were completed. Personnel training, qualifications, management systems and procedures were reviewed and shown to be in place and ready to support the Phase 1B mission. Key assumptions and risks that could negatively impact mission success were evaluated and appropriate mitigative actions plans were planned and scheduled

Radiation analysis for manned missions to the Jupiter system.

Science.gov (United States)

De Angelis, G; Clowdsley, M S; Nealy, J E; Tripathi, R K; Wilson, J W

2004-01-01

An analysis for manned missions targeted to the Jovian system has been performed in the framework of the NASA RASC (Revolutionary Aerospace Systems Concepts) program on Human Exploration beyond Mars. The missions were targeted to the Jupiter satellite Callisto. The mission analysis has been divided into three main phases, namely the interplanetary cruise, the Jupiter orbital insertion, and the surface landing and exploration phases. The interplanetary phase is based on departure from the Earth-Moon L1 point. Interplanetary trajectories based on the use of different propulsion systems have been considered, with resulting overall cruise phase duration varying between two and five years. The Jupiter-approach and the orbital insertion trajectories are considered in detail, with the spacecraft crossing the Jupiter radiation belts and staying around the landing target. In the surface exploration phase the stay on the Callisto surface is considered. The satellite surface composition has been modeled based on the most recent results from the GALILEO spacecraft. In the transport computations the surface backscattering has been duly taken into account. Particle transport has been performed with the HZETRN heavy ion code for hadrons and with an in-house developed transport code for electrons and bremsstrahlung photons. The obtained doses have been compared to dose exposure limits. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Estimated Probability of Traumatic Abdominal Injury During an International Space Station Mission

Science.gov (United States)

Lewandowski, Beth E.; Brooker, John E.; Weavr, Aaron S.; Myers, Jerry G., Jr.; McRae, Michael P.

2013-01-01

The Integrated Medical Model (IMM) is a decision support tool that is useful to spaceflight mission planners and medical system designers when assessing risks and optimizing medical systems. The IMM project maintains a database of medical conditions that could occur during a spaceflight. The IMM project is in the process of assigning an incidence rate, the associated functional impairment, and a best and a worst case end state for each condition. The purpose of this work was to develop the IMM Abdominal Injury Module (AIM). The AIM calculates an incidence rate of traumatic abdominal injury per person-year of spaceflight on the International Space Station (ISS). The AIM was built so that the probability of traumatic abdominal injury during one year on ISS could be predicted. This result will be incorporated into the IMM Abdominal Injury Clinical Finding Form and used within the parent IMM model.

Performance requirements for the double-shell tank system: Phase 1

International Nuclear Information System (INIS)

Claghorn, R.D.

1998-01-01

This document establishes performance requirements for the double-shell tank system. These requirements, in turn, will be incorporated in the System Specification for the Double-Shell Tank System (Grenard and Claghorn 1998). This version of the document establishes requirements that are applicable to the first phase (Phase 1) of the Tank Waste Remediation System (TWRS) mission described in the TWRS Mission Analysis Report (Acree 1998). It does not specify requirements for either the Phase 2 mission or the double-shell tank system closure period

Scheme for implementing N-qubit controlled phase gate of photons assisted by quantum-dot-microcavity coupled system: optimal probability of success

International Nuclear Information System (INIS)

Cui, Wen-Xue; Hu, Shi; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

2015-01-01

The direct implementation of multiqubit controlled phase gate of photons is appealing and important for reducing the complexity of the physical realization of linear-optics-based practical quantum computer and quantum algorithms. In this letter we propose a nondestructive scheme for implementing an N-qubit controlled phase gate of photons with a high success probability. The gate can be directly implemented with the self-designed quantum encoder circuits, which are probabilistic optical quantum entangler devices and can be achieved using linear optical elements, single-photon superposition state, and quantum dot coupled to optical microcavity. The calculated results indicate that both the success probabilities of the quantum encoder circuit and the N-qubit controlled phase gate in our scheme are higher than those in the previous schemes. We also consider the effects of the side leakage and cavity loss on the success probability and the fidelity of the quantum encoder circuit for a realistic quantum-dot-microcavity coupled system. (letter)

Small space reactor power systems for unmanned solar system exploration missions

International Nuclear Information System (INIS)

Bloomfield, H.S.

1987-12-01

A preliminary feasibility study of the application of small nuclear reactor space power systems to the Mariner Mark II Cassini spacecraft/mission was conducted. The purpose of the study was to identify and assess the technology and performance issues associated with the reactor power system/spacecraft/mission integration. The Cassini mission was selected because study of the Saturn system was identified as a high priority outer planet exploration objective. Reactor power systems applied to this mission were evaluated for two different uses. First, a very small 1 kWe reactor power system was used as an RTG replacement for the nominal spacecraft mission science payload power requirements while still retaining the spacecraft's usual bipropellant chemical propulsion system. The second use of reactor power involved the additional replacement of the chemical propulsion system with a small reactor power system and an electric propulsion system. The study also provides an examination of potential applications for the additional power available for scientific data collection. The reactor power system characteristics utilized in the study were based on a parametric mass model that was developed specifically for these low power applications. The model was generated following a neutronic safety and operational feasibility assessment of six small reactor concepts solicited from U.S. industry. This assessment provided the validation of reactor safety for all mission phases and generatad the reactor mass and dimensional data needed for the system mass model

In-flight Integrated Mission Management System (I-LIMMS)

National Research Council Canada - National Science Library

Emmitt, George D; Greco, Steven; Wood, Sidney

2006-01-01

The goal of this Phase I SBIR effort was to determine the feasibility and preliminary design of I-LIMMS, an In-flight Lidar Integrated Mission Management System for the processing and visualization...

Tank waste remediation system retrieval and disposal mission initial updated baseline summary

International Nuclear Information System (INIS)

Swita, W.R.

1998-01-01

This document provides a summary of the proposed Tank Waste Remediation System Retrieval and Disposal Mission Initial Updated Baseline (scope, schedule, and cost) developed to demonstrate the Tank Waste Remediation System contractor's Readiness-to-Proceed in support of the Phase 1B mission

Estimated Probability of a Cervical Spine Injury During an ISS Mission

Science.gov (United States)

Brooker, John E.; Weaver, Aaron S.; Myers, Jerry G.

2013-01-01

Introduction: The Integrated Medical Model (IMM) utilizes historical data, cohort data, and external simulations as input factors to provide estimates of crew health, resource utilization and mission outcomes. The Cervical Spine Injury Module (CSIM) is an external simulation designed to provide the IMM with parameter estimates for 1) a probability distribution function (PDF) of the incidence rate, 2) the mean incidence rate, and 3) the standard deviation associated with the mean resulting from injury/trauma of the neck. Methods: An injury mechanism based on an idealized low-velocity blunt impact to the superior posterior thorax of an ISS crewmember was used as the simulated mission environment. As a result of this impact, the cervical spine is inertially loaded from the mass of the head producing an extension-flexion motion deforming the soft tissues of the neck. A multibody biomechanical model was developed to estimate the kinematic and dynamic response of the head-neck system from a prescribed acceleration profile. Logistic regression was performed on a dataset containing AIS1 soft tissue neck injuries from rear-end automobile collisions with published Neck Injury Criterion values producing an injury transfer function (ITF). An injury event scenario (IES) was constructed such that crew 1 is moving through a primary or standard translation path transferring large volume equipment impacting stationary crew 2. The incidence rate for this IES was estimated from in-flight data and used to calculate the probability of occurrence. The uncertainty in the model input factors were estimated from representative datasets and expressed in terms of probability distributions. A Monte Carlo Method utilizing simple random sampling was employed to propagate both aleatory and epistemic uncertain factors. Scatterplots and partial correlation coefficients (PCC) were generated to determine input factor sensitivity. CSIM was developed in the SimMechanics/Simulink environment with a

Hybrid Propulsion Technology for Robotic Science Missions, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — C3 Propulsion's Hybrid Propulsion Technology will be applied to a NASA selected Sample Return Mission. Phase I will demonstrate Proof-of-Principle and Phase II will...

Tank waste remediation system retrieval and disposal mission key enabling assumptions

International Nuclear Information System (INIS)

Baldwin, J.H.

1998-01-01

An overall systems approach has been applied to develop action plans to support the retrieval and immobilization waste disposal mission. The review concluded that the systems and infrastructure required to support the mission are known. Required systems are either in place or plans have been developed to ensure they exist when needed. The review showed that since October 1996 a robust system engineering approach to establishing integrated Technical Baselines, work breakdown structures, tank farm structure and configurations and work scope and costs has been established itself as part of the culture within TWRS. An analysis of the programmatic, management and technical activities necessary to declare readiness to proceed with execution of the mission demonstrates that the system, people and hardware will be on line and ready to support the private contractors. The systems approach included defining the retrieval and immobilized waste disposal mission requirements and evaluating the readiness of the TWRS contractor to supply waste feed to the private contractors in June 2OO2. The Phase 1 feed delivery requirements from the Private Contractor Request for Proposals were reviewed. Transfer piping routes were mapped out, existing systems were evaluated, and upgrade requirements were defined. Technical Basis Reviews were completed to define work scope in greater detail, cost estimates and associated year by year financial analyses were completed. TWRS personnel training, qualifications, management systems and procedures were reviewed and shown to be in place and ready to support the Phase 1B mission. Key assumptions and risks that could negatively impact mission success were evaluated and appropriate mitigative actions plans were planned and scheduled

Mission,System Design and Payload Aspects of ESA's Mercury Cornerstone Mission

Science.gov (United States)

Ferri, A.; Anselmi, A.; Scoon, G. E. N.

1999-09-01

Aim of this paper is to summarise the 1-year study performed by Alenia Aerospazio in close co-operation with the European Space Agency, on the Mercury Cornerstone System and Technology Study, as a part of Horizon 2000+ Scientific Programme plan. ESA's definition study towards a mission to Mercury conceives the launch of a S/C in 2009, on a two to three years journey, plus a one-year scientific observations and data take. The mission's primary objectives are manyfolded, aiming at approaching basic scientific questions on the origin and evolution of Mercury: identify and map the chemical and mineral composition of the surface, measure the topography of surface landforms, define the gravitational field, investigate particles and magnetic fields. The mission is also intended to resolve the librational state of the planet, in a system experiment requiring high accuracy inertial attitude (arcsecond level) and orbit (m-level) reconstitution. This experiment will allow to infer whether Mercury has a molten core, which is crucial to theories of magnetic field generation, and theories of the thermal history of terrestrial type planets. A hard-lander is planned to perform in-situ surface geochemical analysis. The mission is expected to provide scientists with a global portrait of Mercury returning about 1200 Gbits of scientific data, during a 1-year observation phase. The crucial aspects of the spacecraft design have to do with the high-temperature and high-radiation environment. Thermal control is achieved by a combination of orbit selection, attitude law, and special design provisions for IR shielding and HT insulation. Ad-hoc design provisions are envisaged for power and antenna mechanisms. Though the conceptual objectives of this industrial study focused on system architectures and enabling technologies for a "Cornerstone" class mission, in this paper emphasis is given on the scientific payload aspects.

Envolving the Operations of the TerraSAR-X/TanDEM-X Mission Planning System during the TanDEM-X Science Phase

OpenAIRE

Stathopoulos, Fotios; Guillermin, Guillaume; Garcia Acero, Carlos; Reich, Karin; Mrowka, Falk

2016-01-01

After the successful Global Coverage of the Digital Elevation Model, the TanDEM-X Science phase was initiated in September of 2014, dedicated to the demonstration of innovative techniques and experiments. The TanDEM-X Science phase had a large impact on the TerraSAR-X/TanDEM-X Mission Planning System. The two main challenges were the formation flying changes and the activation of a new acquisition mode, the so called Dual Receive Antenna (DRA) acquisition mode. This paper describes all action...

Status of the assessment phase of the ESA M3 mission candidate LOFT

Science.gov (United States)

Corral van Damme, Carlos; Ayre, Mark; Lumb, David; Short, Alexander D.; Rando, Nicola

2012-09-01

LOFT (Large Observatory For x-ray Timing) is one of four candidates for the M3 slot (launch in 2024, with the option of a launch in 2022) of ESAs Cosmic Vision 2015 - 2025 Plan, and as such it is currently undergoing an initial assessment phase lasting one year. The objective of the assessment phase is to provide the information required to enable the down selection process, in particular: the space segment definition for meeting the assigned science objectives; consideration of and initial definition of the implementation schedule; an estimate of the mission Cost at Completion (CaC); an evaluation of the technology readiness evaluation and risk assessment. The assessment phase is divided into two interleaved components: (i) A payload assessment study, performed by teams funded by member states, which is primarily intended for design, definition and programmatic/cost evaluation of the payload, and (ii) A system industrial study, which has essentially the same objectives for the space segment of the mission. This paper provides an overview of the status of the LOFT assessment phase, both for payload and platform. The initial focus is on the payload design status, providing the reader with an understanding of the main features of the design. Then the space segment assessment study status is presented, with an overview of the principal challenges presented by the LOFT payload and mission requirements, and a presentation of the expected solutions. Overall the mission is expected to enable cutting-edge science, is technically feasible, and should remain within the required CaC for an M3 candidate.

Adaptable Single Active Loop Thermal Control System (TCS) for Future Space Missions

Science.gov (United States)

Mudawar, Issam; Lee, Seunghyun; Hasan, Mohammad

2015-01-01

This presentation will examine the development of a thermal control system (TCS) for future space missions utilizing a single active cooling loop. The system architecture enables the TCS to be reconfigured during the various mission phases to respond, not only to varying heat load, but to heat rejection temperature as well. The system will consist of an accumulator, pump, cold plates (evaporators), condenser radiator, and compressor, in addition to control, bypass and throttling valves. For cold environments, the heat will be rejected by radiation, during which the compressor will be bypassed, reducing the system to a simple pumped loop that, depending on heat load, can operate in either a single-phase liquid mode or two-phase mode. For warmer environments, the pump will be bypassed, enabling the TCS to operate as a heat pump. This presentation will focus on recent findings concerning two-phase flow regimes, pressure drop, and heat transfer coefficient trends in the cabin and avionics micro-channel heat exchangers when using the heat pump mode. Also discussed will be practical implications of using micro-channel evaporators for the heat pump.

A phase one AR/C system design

Science.gov (United States)

Kachmar, Peter M.; Polutchko, Robert J.; Matusky, Martin; Chu, William; Jackson, William; Montez, Moises

1991-01-01

The Phase One AR&C System Design integrates an evolutionary design based on the legacy of previous mission successes, flight tested components from manned Rendezvous and Proximity Operations (RPO) space programs, and additional AR&C components validated using proven methods. The Phase One system has a modular, open architecture with the standardized interfaces proposed for Space Station Freedom system architecture.

Sustainable, Reliable Mission-Systems Architecture

Science.gov (United States)

O'Neil, Graham; Orr, James K.; Watson, Steve

2007-01-01

A mission-systems architecture, based on a highly modular infrastructure utilizing: open-standards hardware and software interfaces as the enabling technology is essential for affordable and sustainable space exploration programs. This mission-systems architecture requires (a) robust communication between heterogeneous system, (b) high reliability, (c) minimal mission-to-mission reconfiguration, (d) affordable development, system integration, and verification of systems, and (e) minimal sustaining engineering. This paper proposes such an architecture. Lessons learned from the Space Shuttle program and Earthbound complex engineered system are applied to define the model. Technology projections reaching out 5 years are mde to refine model details.

Magnetospheric Multiscale (MMS) Mission Attitude Ground System Design

Science.gov (United States)

Sedlak, Joseph E.; Superfin, Emil; Raymond, Juan C.

2011-01-01

This paper describes the attitude ground system (AGS) design to be used for support of the Magnetospheric MultiScale (MMS) mission. The AGS exists as one component of the mission operations control center. It has responsibility for validating the onboard attitude and accelerometer bias estimates, calibrating the attitude sensors and the spacecraft inertia tensor, and generating a definitive attitude history for use by the science teams. NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Maryland is responsible for developing the MMS spacecraft, for the overall management of the MMS mission, and for mission operations. MMS is scheduled for launch in 2014 for a planned two-year mission. The MMS mission consists of four identical spacecraft flying in a tetrahedral formation in an eccentric Earth orbit. The relatively tight formation, ranging from 10 to 400 km, will provide coordinated observations giving insight into small-scale magnetic field reconnection processes. By varying the size of the tetrahedron and the orbital semi-major axis and eccentricity, and making use of the changing solar phase, this geometry allows for the study of both bow shock and magnetotail plasma physics, including acceleration, reconnection, and turbulence. The mission divides into two phases for science; these phases will have orbit dimensions of l.2xl2 Earth radii in the first phase and l.2x25 Earth radii in the second in order to study the dayside magnetopause and the nightside magnetotail, respectively. The orbital periods are roughly one day and three days for the two mission phases. Each of the four MMS spacecraft will be spin stabilized at 3 revolutions per minute (rpm), with the spin axis oriented near the ecliptic north pole but tipped approximately 2.5 deg towards the Sun line. The main body of each spacecraft will be an eight-sided platform with diameter of 3.4 m and height of 1.2 m. Several booms are attached to this central core: two axial booms of 14.9 m length, two radial

Probabilistic Design Analysis (PDA) Approach to Determine the Probability of Cross-System Failures for a Space Launch Vehicle

Science.gov (United States)

Shih, Ann T.; Lo, Yunnhon; Ward, Natalie C.

2010-01-01

Quantifying the probability of significant launch vehicle failure scenarios for a given design, while still in the design process, is critical to mission success and to the safety of the astronauts. Probabilistic risk assessment (PRA) is chosen from many system safety and reliability tools to verify the loss of mission (LOM) and loss of crew (LOC) requirements set by the NASA Program Office. To support the integrated vehicle PRA, probabilistic design analysis (PDA) models are developed by using vehicle design and operation data to better quantify failure probabilities and to better understand the characteristics of a failure and its outcome. This PDA approach uses a physics-based model to describe the system behavior and response for a given failure scenario. Each driving parameter in the model is treated as a random variable with a distribution function. Monte Carlo simulation is used to perform probabilistic calculations to statistically obtain the failure probability. Sensitivity analyses are performed to show how input parameters affect the predicted failure probability, providing insight for potential design improvements to mitigate the risk. The paper discusses the application of the PDA approach in determining the probability of failure for two scenarios from the NASA Ares I project

Design and validation of a GNC system for missions to asteroids: the AIM scenario

Science.gov (United States)

Pellacani, A.; Kicman, P.; Suatoni, M.; Casasco, M.; Gil, J.; Carnelli, I.

2017-12-01

Deep space missions, and in particular missions to asteroids, impose a certain level of autonomy that depends on the mission objectives. If the mission requires the spacecraft to perform close approaches to the target body (the extreme case being a landing scenario), the autonomy level must be increased to guarantee the fast and reactive response which is required in both nominal and contingency operations. The GNC system must be designed in accordance with the required level of autonomy. The GNC system designed and tested in the frame of ESA's Asteroid Impact Mission (AIM) system studies (Phase A/B1 and Consolidation Phase) is an example of an autonomous GNC system that meets the challenging objectives of AIM. The paper reports the design of such GNC system and its validation through a DDVV plan that includes Model-in-the-Loop and Hardware-in-the-Loop testing. Main focus is the translational navigation, which is able to provide online the relative state estimation with respect to the target body using exclusively cameras as relative navigation sensors. The relative navigation outputs are meant to be used for nominal spacecraft trajectory corrections as well as to estimate the collision risk with the asteroid and, if needed, to command the execution of a collision avoidance manoeuvre to guarantee spacecraft safety

Integration of CubeSat Systems with Europa Surface Exploration Missions

Science.gov (United States)

Erdoǧan, Enes; Inalhan, Gokhan; Kemal Üre, Nazım

2016-07-01

Recent studies show that there is a high probability that a liquid ocean exists under thick icy surface of Jupiter's Moon Europa. The findings also show that Europa has features that are similar to Earth, such as geological activities. As a result of these studies, Europa has promising environment of being habitable and currently there are many missions in both planning and execution level that target Europa. However, these missions usually involve extremely high budgets over extended periods of time. The objective of this talk is to argue that the mission costs can be reduced significantly by integrating CubeSat systems within Europa exploration missions. In particular, we introduce an integrated CubeSat-micro probe system, which can be used for measuring the size and depth of the hypothetical liquid ocean under the icy surface of Europa. The systems consist of an entry module that houses a CubeSat combined with driller measurement probes. Driller measurement probes deploy before the system hits the surface and penetrate the surface layers of Europa. Moreover, a micro laser probe could be used to examine the layers. This process enables investigation of the properties of the icy layer and the environment beneath the surface. Through examination of different scenarios and cost analysis of the components, we show that the proposed CubeSat systems has a significant potential to reduce the cost of the overall mission. Both subsystem requirements and launch prices of CubeSats are dramatically cheaper than currently used satellites. In addition, multiple CubeSats may be used to dominate wider area in space and they are expandable in face of potential failures. In this talk we discuss both the mission design and cost reduction aspects.

An analysis of the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)

Energy Technology Data Exchange (ETDEWEB)

Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J.

1995-11-01

The Environmental Evaluation Group (EEG) previously analyzed the probability of a catastrophic accident in the waste hoist of the Waste Isolation Pilot Plant (WIPP) and published the results in Greenfield (1990; EEG-44) and Greenfield and Sargent (1993; EEG-53). The most significant safety element in the waste hoist is the hydraulic brake system, whose possible failure was identified in these studies as the most important contributor in accident scenarios. Westinghouse Electric Corporation, Waste Isolation Division has calculated the probability of an accident involving the brake system based on studies utilizing extensive fault tree analyses. This analysis conducted for the U.S. Department of Energy (DOE) used point estimates to describe the probability of failure and includes failure rates for the various components comprising the brake system. An additional controlling factor in the DOE calculations is the mode of operation of the brake system. This factor enters for the following reason. The basic failure rate per annum of any individual element is called the Event Probability (EP), and is expressed as the probability of failure per annum. The EP in turn is the product of two factors. One is the {open_quotes}reported{close_quotes} failure rate, usually expressed as the probability of failure per hour and the other is the expected number of hours that the element is in use, called the {open_quotes}mission time{close_quotes}. In many instances the {open_quotes}mission time{close_quotes} will be the number of operating hours of the brake system per annum. However since the operation of the waste hoist system includes regular {open_quotes}reoperational check{close_quotes} tests, the {open_quotes}mission time{close_quotes} for standby components is reduced in accordance with the specifics of the operational time table.

An analysis of the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)

International Nuclear Information System (INIS)

Greenfield, M.A.; Sargent, T.J.

1995-11-01

The Environmental Evaluation Group (EEG) previously analyzed the probability of a catastrophic accident in the waste hoist of the Waste Isolation Pilot Plant (WIPP) and published the results in Greenfield (1990; EEG-44) and Greenfield and Sargent (1993; EEG-53). The most significant safety element in the waste hoist is the hydraulic brake system, whose possible failure was identified in these studies as the most important contributor in accident scenarios. Westinghouse Electric Corporation, Waste Isolation Division has calculated the probability of an accident involving the brake system based on studies utilizing extensive fault tree analyses. This analysis conducted for the U.S. Department of Energy (DOE) used point estimates to describe the probability of failure and includes failure rates for the various components comprising the brake system. An additional controlling factor in the DOE calculations is the mode of operation of the brake system. This factor enters for the following reason. The basic failure rate per annum of any individual element is called the Event Probability (EP), and is expressed as the probability of failure per annum. The EP in turn is the product of two factors. One is the open-quotes reportedclose quotes failure rate, usually expressed as the probability of failure per hour and the other is the expected number of hours that the element is in use, called the open-quotes mission timeclose quotes. In many instances the open-quotes mission timeclose quotes will be the number of operating hours of the brake system per annum. However since the operation of the waste hoist system includes regular open-quotes reoperational checkclose quotes tests, the open-quotes mission timeclose quotes for standby components is reduced in accordance with the specifics of the operational time table

Mission-Critical Systems Design Framework

Directory of Open Access Journals (Sweden)

Kyriakos Houliotis

2018-03-01

Full Text Available Safety-critical systems are well documented and standardized (e.g. IEC 61508, RTCA DO-178B within system design cycles. However in Defence and Security, systems that are critical to the success of a Mission are not defined within the literature nor are there any guidelines in defining criticality in their design or operational capabilities. When it comes to Vetronics (Vehicle Electronics, a mission-critical system, is a system with much complexity and mixed criticality levels that is a part of the overall platform (military vehicle offering integrated system capabilities. In this paper, a framework is presented, providing guidelines in designing efficiently and effectively mission-critical systems considering principles of Interoperable Open Architectures (IOA, mission-critical integrity levels and following new standardization activities such as NATO Generic Vehicle Architecture (NGVA. A Defensive Aid Suite (DAS system is used as a case study to illustrate how this framework can be exploited. The indention of this extension is to provide an approach to precisely estimate threats in order to de-risk missions in the very early stages.

Probability of islanding in utility networks due to grid connected photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

Verhoeven, B.

2002-09-15

This report for the International Energy Agency (IEA) made by Task 5 of the Photovoltaic Power Systems (PVPS) programme takes a look at the probability of islanding in utility networks due to grid-connected photovoltaic power systems. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. Task 5 deals with issues concerning grid-interconnection and distributed PV power systems. This report summarises the results on a study on the probability of islanding in power networks with a high penetration level of grid connected PV-systems. The results are based on measurements performed during one year in a Dutch utility network. The measurements of active and reactive power were taken every second for two years and stored in a computer for off-line analysis. The area examined and its characteristics are described, as are the test set-up and the equipment used. The ratios between load and PV-power are discussed. The general conclusion is that the probability of islanding is virtually zero for low, medium and high penetration levels of PV-systems.

Overview of the Development and Mission Application of the Advanced Electric Propulsion System (AEPS)

Science.gov (United States)

Herman, Daniel A.; Tofil, Todd A.; Santiago, Walter; Kamhawi, Hani; Polk, James E.; Snyder, John S.; Hofer, Richard R.; Picha, Frank Q.; Jackson, Jerry; Allen, May

2018-01-01

NASA remains committed to the development and demonstration of a high-power solar electric propulsion capability for the Agency. NASA is continuing to develop the 14 kW Advanced Electric Propulsion System (AEPS), which has recently completed an Early Integrated System Test and System Preliminary Design Review. NASA continues to pursue Solar Electric Propulsion (SEP) Technology Demonstration Mission partners and mature high-power SEP mission concepts. The recent announcement of the development of a Power and Propulsion Element (PPE) as the first element of an evolvable human architecture to Mars has replaced the Asteroid Redirect Robotic Mission (ARRM) as the most probable first application of the AEPS Hall thruster system. This high-power SEP capability, or an extensible derivative of it, has been identified as a critical part of an affordable, beyond-low-Earth-orbit, manned exploration architecture. This paper presents the status of the combined NASA and Aerojet Rocketdyne AEPS development activities and updated mission concept for implementation of the AEPS hardware as part of the ion propulsion system for a PPE.

The Integrated Medical Model - Optimizing In-flight Space Medical Systems to Reduce Crew Health Risk and Mission Impacts

Science.gov (United States)

Kerstman, Eric; Walton, Marlei; Minard, Charles; Saile, Lynn; Myers, Jerry; Butler, Doug; Lyengar, Sriram; Fitts, Mary; Johnson-Throop, Kathy

2009-01-01

The Integrated Medical Model (IMM) is a decision support tool used by medical system planners and designers as they prepare for exploration planning activities of the Constellation program (CxP). IMM provides an evidence-based approach to help optimize the allocation of in-flight medical resources for a specified level of risk within spacecraft operational constraints. Eighty medical conditions and associated resources are represented in IMM. Nine conditions are due to Space Adaptation Syndrome. The IMM helps answer fundamental medical mission planning questions such as What medical conditions can be expected? What type and quantity of medical resources are most likely to be used?", and "What is the probability of crew death or evacuation due to medical events?" For a specified mission and crew profile, the IMM effectively characterizes the sequence of events that could potentially occur should a medical condition happen. The mathematical relationships among mission and crew attributes, medical conditions and incidence data, in-flight medical resources, potential clinical and crew health end states are established to generate end state probabilities. A Monte Carlo computational method is used to determine the probable outcomes and requires up to 25,000 mission trials to reach convergence. For each mission trial, the pharmaceuticals and supplies required to diagnose and treat prevalent medical conditions are tracked and decremented. The uncertainty of patient response to treatment is bounded via a best-case, worst-case, untreated case algorithm. A Crew Health Index (CHI) metric, developed to account for functional impairment due to a medical condition, provides a quantified measure of risk and enables risk comparisons across mission scenarios. The use of historical in-flight medical data, terrestrial surrogate data as appropriate, and space medicine subject matter expertise has enabled the development of a probabilistic, stochastic decision support tool capable of

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Colombia

International Nuclear Information System (INIS)

1984-01-01

A full report has been released describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Colombia. The Mission suggests that the speculative uranium resources of the country could be within the very wide range of 20 000 tonnes of 220 000 tonnes of uranium metal. The Mission finds that the area with the highest potential is the Llanos Orientales (Interior Zone), which has the potential of hosting quartz-pebble conglomerate deposits, Proterozoic unconformity-related deposits and sandstone deposits. The Mission recommends that approximately US$80 million should be expended in a phased ten-year exploration programme. It is likely that the majority of the funds will be needed for drilling, followed by ground surveys and airborne radiometry. It is the opinion of the Mission that the considerable funds required for the proposed programme could most suitably be raised by inviting national or foreign commercial organizations to participate under a shared production agreement. (author)

Mission Analysis for the Don Quijote Phase-A Study

Science.gov (United States)

Cano, Juan L.; Sanchez, Mariano; Cornara, Stefania; Carnelli, Ian

2007-01-01

The Don Quijote Phase-A study is a definition study funded by ESA and devoted to the analysis of the possibilities to deflect a Near Earth Object (NEO) in the range of 300-800 m diameter. DEIMOS Space S.L. and EADS Astrium have teamed up within this study to form one of the three consortia that have analyzed these aspects for ESA. Target asteroids for the mission are 1989 ML, 2002 AT4 and Apophis. This paper presents the mission analysis activities within the consortium providing: low-thrust interplanetary rendezvous Orbiter trajectories to the target asteroids, ballistic interplanetary trajectories for the Impactor, Orbiter arrival description at the asteroids, Orbiter stable orbits characterization at the asteroid, deflection determination by means of a Radio Science Experiment (RSE) as well as the mission timelines and overall mission scenarios.

Core Science Systems--Mission overview

Science.gov (United States)

Gallagher, Kevin T.

2012-01-01

The Core Science Systems Mission Area delivers nationally focused Earth systems and information science that provides fundamental research and data that underpins all Mission Areas of the USGS, the USGS Science Strategy, and Presidential, Secretarial, and societal priorities. —Kevin T. Gallagher, Associate Director, Core Science Systems

Identification of Mission Sensitivities with Mission Modeling from the One System Organization at Hanford - 13292

Energy Technology Data Exchange (ETDEWEB)

Belsher, Jeremy D.; Pierson, Kayla L. [Washington River Protection Solutions, LLC, Richland, WA 99352 (United States); Gimpel, Rod F. [One System - Waste Treatment Project, Richland, WA 99352 (United States)

2013-07-01

The Hanford site in southeast Washington contains approximately 207 million liters of radioactive and hazardous waste stored in 177 underground tanks. The U.S. Department of Energy's Office of River Protection is currently managing the Hanford waste treatment mission, which includes the storage, retrieval, treatment and disposal of the tank waste. Two recent studies, employing the modeling tools managed by the One System organization, have highlighted waste cleanup mission sensitivities. The Hanford Tank Waste Operations Simulator Sensitivity Study evaluated the impact that varying 21 different parameters had on the Hanford Tank Waste Operations Simulator model. It concluded that inaccuracies in the predicted phase partitioning of a few key components can result in significant changes in the waste treatment duration and in the amount of immobilized high-level waste that is produced. In addition, reducing the efficiency with which tank waste is retrieved and staged can increase mission duration. The 2012 WTP Tank Utilization Assessment concluded that flowsheet models need to include the latest low-activity waste glass algorithms or the waste treatment mission duration and the amount of low activity waste that is produced could be significantly underestimated. (authors)

Cascade Distillation System Design for Safety and Mission Assurance

Science.gov (United States)

Sarguisingh, Miriam; Callahan, Michael R.; Okon, Shira

2015-01-01

Per the NASA Human Health, Life Support and Habitation System Technology Area 06 report "crewed missions venturing beyond Low-Earth Orbit (LEO) will require technologies with improved reliability, reduced mass, self-sufficiency, and minimal logistical needs as an emergency or quick-return option will not be feasible".1 To meet this need, the development team of the second generation Cascade Distillation System (CDS 2.0) chose a development approach that explicitly incorporate consideration of safety, mission assurance, and autonomy. The CDS 2.0 preliminary design focused on establishing a functional baseline that meets the CDS core capabilities and performance. The critical design phase is now focused on incorporating features through a deliberative process of establishing the systems failure modes and effects, identifying mitigation strategies, and evaluating the merit of the proposed actions through analysis and test. This paper details results of this effort on the CDS 2.0 design.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Portugal

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Portugal. The IUREP Orientation Phase mission to Portugal estimates that the Speculative Resources of that country fall within the range 20,000 to 80,000 tonnes uranium. The majority of this potential is expected to be located in intergranitic vein deposits and in pre-Ordovician schists, but other favourable geological environments include episyenites and Meso-Cainozoic continental sediments. The mission recommends that approximately US$25 million be spent on exploration in Portugal over the next 10 years. The majority of this ($18 million) would be spent on drilling, with a further $7 million on surface surveys and airborne radiometric surveys. It is the opinion of the IUREP Orientation Phase Mission that the considerable funding required for the outlined programme would most suitably be realized by inviting national or foreign commercial organisations to participate in the exploration effort under a partnership or shared production arrangements. (author)

Software-Defined Ground Stations - Enhancing Multi-Mission Support, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This SBIR Phase 1 proposal to NASA requests $99,055.69 to enhance multiple mission support in ground stations through the use of software defined radios and virtual...

Phase 1 space fission propulsion system design considerations

International Nuclear Information System (INIS)

Houts, Mike; Van Dyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbud, Ivana; Carter, Robert

2002-01-01

Fission technology can enable rapid, affordable access to any point in the solar system. If fission propulsion systems are to be developed to their full potential; however, near-term customers must be identified and initial fission systems successfully developed, launched, and operated. Studies conducted in fiscal year 2001 (IISTP, 2001) show that fission electric propulsion (FEP) systems operating at 80 kWe or above could enhance or enable numerous robotic outer solar system missions of interest. At these power levels it is possible to develop safe, affordable systems that meet mission performance requirements. In selecting the system design to pursue, seven evaluation criteria were identified: safety, reliability, testability, specific mass, cost, schedule, and programmatic risk. A top-level comparison of three potential concepts was performed: an SP-100 based pumped liquid lithium system, a direct gas cooled system, and a heatpipe cooled system. For power levels up to at least 500 kWt (enabling electric power levels of 125-175 kWe, given 25-35% power conversion efficiency) the heatpipe system has advantages related to several criteria and is competitive with respect to all. Hardware-based research and development has further increased confidence in the heatpipe approach. Successful development and utilization of a 'Phase 1' fission electric propulsion system will enable advanced Phase 2 and Phase 3 systems capable of providing rapid, affordable access to any point in the solar system

Designing Mission Operations for the Gravity Recovery and Interior Laboratory Mission

Science.gov (United States)

Havens, Glen G.; Beerer, Joseph G.

2012-01-01

NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, to understand the internal structure and thermal evolution of the Moon, offered unique challenges to mission operations. From launch through end of mission, the twin GRAIL orbiters had to be operated in parallel. The journey to the Moon and into the low science orbit involved numerous maneuvers, planned on tight timelines, to ultimately place the orbiters into the required formation-flying configuration necessary. The baseline GRAIL mission is short, only 9 months in duration, but progressed quickly through seven very unique mission phases. Compressed into this short mission timeline, operations activities and maneuvers for both orbiters had to be planned and coordinated carefully. To prepare for these challenges, development of the GRAIL Mission Operations System began in 2008. Based on high heritage multi-mission operations developed by NASA's Jet Propulsion Laboratory and Lockheed Martin, the GRAIL mission operations system was adapted to meet the unique challenges posed by the GRAIL mission design. This paper describes GRAIL's system engineering development process for defining GRAIL's operations scenarios and generating requirements, tracing the evolution from operations concept through final design, implementation, and validation.

Definition phase of Grand Tour missions/radio science investigations study for outer planets missions

Science.gov (United States)

Tyler, G. L.

1972-01-01

Scientific instrumentation for satellite communication and radio tracking systems in the outer planet exploration mission is discussed. Mission planning considers observations of planetary and satellite-masses, -atmospheres, -magnetic fields, -surfaces, -gravitational fields, solar wind composition, planetary radio emissions, and tests of general relativity in time delay and ray bending experiments.

Tank waste remediation system retrieval and disposal mission initial updated baseline summary

International Nuclear Information System (INIS)

Swita, W.R.

1998-01-01

This document provides a summary of the Tank Waste Remediation System (TWRS) Retrieval and Disposal Mission Initial Updated Baseline (scope, schedule, and cost), developed to demonstrate Readiness-to-Proceed (RTP) in support of the TWRS Phase 1B mission. This Updated Baseline is the proposed TWRS plan to execute and measure the mission work scope. This document and other supporting data demonstrate that the TWRS Project Hanford Management Contract (PHMC) team is prepared to fully support Phase 1B by executing the following scope, schedule, and cost baseline activities: Deliver the specified initial low-activity waste (LAW) and high-level waste (HLW) feed batches in a consistent, safe, and reliable manner to support private contractors' operations starting in June 2002; Deliver specified subsequent LAW and HLW feed batches during Phase 1B in a consistent, safe, and reliable manner; Provide for the interim storage of immobilized HLW (IHLW) products and the disposal of immobilized LAW (ILAW) products generated by the private contractors; Provide for disposal of byproduct wastes generated by the private contractors; and Provide the infrastructure to support construction and operations of the private contractors' facilities

Dynamic phase transitions of the Blume–Emery–Griffiths model under an oscillating external magnetic field by the path probability method

Energy Technology Data Exchange (ETDEWEB)

Ertaş, Mehmet, E-mail: mehmetertas@erciyes.edu.tr; Keskin, Mustafa

2015-03-01

By using the path probability method (PPM) with point distribution, we study the dynamic phase transitions (DPTs) in the Blume–Emery–Griffiths (BEG) model under an oscillating external magnetic field. The phases in the model are obtained by solving the dynamic equations for the average order parameters and a disordered phase, ordered phase and four mixed phases are found. We also investigate the thermal behavior of the dynamic order parameters to analyze the nature dynamic transitions as well as to obtain the DPT temperatures. The dynamic phase diagrams are presented in three different planes in which exhibit the dynamic tricritical point, double critical end point, critical end point, quadrupole point, triple point as well as the reentrant behavior, strongly depending on the values of the system parameters. We compare and discuss the dynamic phase diagrams with dynamic phase diagrams that were obtained within the Glauber-type stochastic dynamics based on the mean-field theory. - Highlights: • Dynamic magnetic behavior of the Blume–Emery–Griffiths system is investigated by using the path probability method. • The time variations of average magnetizations are studied to find the phases. • The temperature dependence of the dynamic magnetizations is investigated to obtain the dynamic phase transition points. • We compare and discuss the dynamic phase diagrams with dynamic phase diagrams that were obtained within the Glauber-type stochastic dynamics based on the mean-field theory.

Dynamic phase transitions of the Blume–Emery–Griffiths model under an oscillating external magnetic field by the path probability method

International Nuclear Information System (INIS)

Ertaş, Mehmet; Keskin, Mustafa

2015-01-01

By using the path probability method (PPM) with point distribution, we study the dynamic phase transitions (DPTs) in the Blume–Emery–Griffiths (BEG) model under an oscillating external magnetic field. The phases in the model are obtained by solving the dynamic equations for the average order parameters and a disordered phase, ordered phase and four mixed phases are found. We also investigate the thermal behavior of the dynamic order parameters to analyze the nature dynamic transitions as well as to obtain the DPT temperatures. The dynamic phase diagrams are presented in three different planes in which exhibit the dynamic tricritical point, double critical end point, critical end point, quadrupole point, triple point as well as the reentrant behavior, strongly depending on the values of the system parameters. We compare and discuss the dynamic phase diagrams with dynamic phase diagrams that were obtained within the Glauber-type stochastic dynamics based on the mean-field theory. - Highlights: • Dynamic magnetic behavior of the Blume–Emery–Griffiths system is investigated by using the path probability method. • The time variations of average magnetizations are studied to find the phases. • The temperature dependence of the dynamic magnetizations is investigated to obtain the dynamic phase transition points. • We compare and discuss the dynamic phase diagrams with dynamic phase diagrams that were obtained within the Glauber-type stochastic dynamics based on the mean-field theory

VIBRATION ISOLATION SYSTEM PROBABILITY ANALYSIS

Directory of Open Access Journals (Sweden)

Smirnov Vladimir Alexandrovich

2012-10-01

Full Text Available The article deals with the probability analysis for a vibration isolation system of high-precision equipment, which is extremely sensitive to low-frequency oscillations even of submicron amplitude. The external sources of low-frequency vibrations may include the natural city background or internal low-frequency sources inside buildings (pedestrian activity, HVAC. Taking Gauss distribution into account, the author estimates the probability of the relative displacement of the isolated mass being still lower than the vibration criteria. This problem is being solved in the three dimensional space, evolved by the system parameters, including damping and natural frequency. According to this probability distribution, the chance of exceeding the vibration criteria for a vibration isolation system is evaluated. Optimal system parameters - damping and natural frequency - are being developed, thus the possibility of exceeding vibration criteria VC-E and VC-D is assumed to be less than 0.04.

Parametric cost estimation for space science missions

Science.gov (United States)

Lillie, Charles F.; Thompson, Bruce E.

2008-07-01

Cost estimation for space science missions is critically important in budgeting for successful missions. The process requires consideration of a number of parameters, where many of the values are only known to a limited accuracy. The results of cost estimation are not perfect, but must be calculated and compared with the estimates that the government uses for budgeting purposes. Uncertainties in the input parameters result from evolving requirements for missions that are typically the "first of a kind" with "state-of-the-art" instruments and new spacecraft and payload technologies that make it difficult to base estimates on the cost histories of previous missions. Even the cost of heritage avionics is uncertain due to parts obsolescence and the resulting redesign work. Through experience and use of industry best practices developed in participation with the Aerospace Industries Association (AIA), Northrop Grumman has developed a parametric modeling approach that can provide a reasonably accurate cost range and most probable cost for future space missions. During the initial mission phases, the approach uses mass- and powerbased cost estimating relationships (CER)'s developed with historical data from previous missions. In later mission phases, when the mission requirements are better defined, these estimates are updated with vendor's bids and "bottoms- up", "grass-roots" material and labor cost estimates based on detailed schedules and assigned tasks. In this paper we describe how we develop our CER's for parametric cost estimation and how they can be applied to estimate the costs for future space science missions like those presented to the Astronomy & Astrophysics Decadal Survey Study Committees.

Final Phase Flight Performance and Touchdown Time Assessment of TDV in RLV-TD HEX-01 Mission

Science.gov (United States)

Yadav, Sandeep; Jayakumar, M.; Nizin, Aziya; Kesavabrahmaji, K.; Shyam Mohan, N.

2017-12-01

RLV-TD HEX-01 mission was configured as a precursor flight to actual two stages to orbit vehicle. In this mission RLV-TD was designed as a two stage vehicle for demonstrating the hypersonic flight of a winged body vehicle at Mach No. 5. One of the main objectives of this mission was to generate data for better understanding of new technologies required to design the future vehicle. In this mission, the RLV-TD vehicle was heavily instrumented to get data related to performance of different subsystems. As per the mission design, RLV-TD will land in sea after flight duration of 700 s and travelling a distance of nearly 500 km in Bay of Bengal from the launch site for a nominal trajectory. The visibility studies for telemetry data of vehicle for the nominal and off nominal trajectories were carried out. Based on that, three ground stations were proposed for the telemetry data reception (including one in sea). Even with this scheme it was seen that during the final phase of the flight there will not be any ground station visible to the flight due to low elevation. To have the mission critical data during final phase of the flight, telemetry through INSAT scheme was introduced. During the end of the mission RLV-TD will be landing in the sea on a hypothetical runway. To know the exact time of touchdown for the flight in sea, there was no direct measurement available. Simultaneously there were all chances of losing ground station visibility just before touchdown, making it difficult to assess flight performance during that phase. In this work, telemetry and instrumentation scheme of RLV-TD HEX-01 mission is discussed with an objective to determine the flight performance during the final phase. Further, using various flight sensor data the touchdown time of TDV is assessed for this mission.

Maqarin natural analogue project: Phase IV. Reconnaissance mission report (April 28 to May 7, 1999)

International Nuclear Information System (INIS)

Smellie, J.A.T.

2000-08-01

Final planning of the Technical Proposal for Phase IV of the Maqarin Natural Analogue Project was preceded by a ten day Reconnaissance Mission to the Jordan sites. The main objective of this mission was to: i) allow new organisations within the project to become familiar with the geological context of the Maqarin and Central Jordan sites and also to appreciate the prevailing technical and logistical limitations, ii) carry out limited field investigations, and iii) based on the experience from these two points, provide the opportunity to finalise the Maqarin Phase IV Technical Proposal. This report details the results of the mission

Maqarin natural analogue project: Phase IV. Reconnaissance mission report (April 28 to May 7, 1999)

Energy Technology Data Exchange (ETDEWEB)

Smellie, J.A.T. [ed.] [Conterra AB, Uppsala (Sweden)

2000-08-01

Final planning of the Technical Proposal for Phase IV of the Maqarin Natural Analogue Project was preceded by a ten day Reconnaissance Mission to the Jordan sites. The main objective of this mission was to: i) allow new organisations within the project to become familiar with the geological context of the Maqarin and Central Jordan sites and also to appreciate the prevailing technical and logistical limitations, ii) carry out limited field investigations, and iii) based on the experience from these two points, provide the opportunity to finalise the Maqarin Phase IV Technical Proposal. This report details the results of the mission.

Mission operations update for the restructured Earth Observing System (EOS) mission

Science.gov (United States)

Kelly, Angelita Castro; Chang, Edward S.

1993-01-01

The National Aeronautics and Space Administration's (NASA) Earth Observing System (EOS) will provide a comprehensive long term set of observations of the Earth to the Earth science research community. The data will aid in determining global changes caused both naturally and through human interaction. Understanding man's impact on the global environment will allow sound policy decisions to be made to protect our future. EOS is a major component of the Mission to Planet Earth program, which is NASA's contribution to the U.S. Global Change Research Program. EOS consists of numerous instruments on multiple spacecraft and a distributed ground system. The EOS Data and Information System (EOSDIS) is the major ground system developed to support EOS. The EOSDIS will provide EOS spacecraft command and control, data processing, product generation, and data archival and distribution services for EOS spacecraft. Data from EOS instruments on other Earth science missions (e.g., Tropical Rainfall Measuring Mission (TRMM)) will also be processed, distributed, and archived in EOSDIS. The U.S. and various International Partners (IP) (e.g., the European Space Agency (ESA), the Ministry of International Trade and Industry (MITI) of Japan, and the Canadian Space Agency (CSA)) participate in and contribute to the international EOS program. The EOSDIS will also archive processed data from other designated NASA Earth science missions (e.g., UARS) that are under the broad umbrella of Mission to Planet Earth.

Thermal analysis of hybrid single-phase, two-phase and heat pump thermal control system (TCS) for future spacecraft

International Nuclear Information System (INIS)

Lee, S.H.; Mudawar, I.; Hasan, Mohammad M.

2016-01-01

Highlights: • Hybrid Thermal Control System (H-TCS) is proposed for future spacecraft. • Thermodynamic performance of H-TCS is examined for different space missions. • Operational modes including single-phase, two-phase and heat pump are explored. • R134a is deemed most appropriate working fluid. - Abstract: An urgent need presently exists to develop a new class of versatile spacecraft capable of conducting different types of missions and enduring varying gravitational and temperature environments, including Lunar, Martian and Near Earth Object (NEOs). This study concerns the spacecraft's Thermal Control System (TCS), which tackles heat acquisition, especially from crew and avionics, heat transport, and ultimate heat rejection by radiation. The primary goal of the study is to explore the design and thermal performance of a Hybrid Thermal Control System (H-TCS) that would satisfy the diverse thermal requirements of the different space missions. The H-TCS must endure both ‘cold’ and ‘hot’ environments, reduce weight and size, and enhance thermodynamic performance. Four different operational modes are considered: single-phase, two-phase, basic heat pump and heat pump with liquid-side, suction-side heat exchanger. A thermodynamic trade study is conducted for six different working fluids to assess important performance parameters including mass flow rate of the working fluid, maximum pressure, radiator area, compressor/pump work, and coefficient of performance (COP). R134a is determined to be most suitable based on its ability to provide a balanced compromise between reducing flow rate and maintaining low system pressure, and a moderate coefficient of performance (COP); this fluid is also both nontoxic and nonflammable, and features zero ozone depletion potential (ODP) and low global warming potential (GWP). It is shown how specific mission stages dictate which mode of operation is most suitable, and this information is used to size the radiator for the

Error Probability Analysis of Hardware Impaired Systems with Asymmetric Transmission

KAUST Repository

Javed, Sidrah; Amin, Osama; Ikki, Salama S.; Alouini, Mohamed-Slim

2018-01-01

Error probability study of the hardware impaired (HWI) systems highly depends on the adopted model. Recent models have proved that the aggregate noise is equivalent to improper Gaussian signals. Therefore, considering the distinct noise nature and self-interfering (SI) signals, an optimal maximum likelihood (ML) receiver is derived. This renders the conventional minimum Euclidean distance (MED) receiver as a sub-optimal receiver because it is based on the assumptions of ideal hardware transceivers and proper Gaussian noise in communication systems. Next, the average error probability performance of the proposed optimal ML receiver is analyzed and tight bounds and approximations are derived for various adopted systems including transmitter and receiver I/Q imbalanced systems with or without transmitter distortions as well as transmitter or receiver only impaired systems. Motivated by recent studies that shed the light on the benefit of improper Gaussian signaling in mitigating the HWIs, asymmetric quadrature amplitude modulation or phase shift keying is optimized and adapted for transmission. Finally, different numerical and simulation results are presented to support the superiority of the proposed ML receiver over MED receiver, the tightness of the derived bounds and effectiveness of asymmetric transmission in dampening HWIs and improving overall system performance

Error Probability Analysis of Hardware Impaired Systems with Asymmetric Transmission

KAUST Repository

Javed, Sidrah

2018-04-26

Error probability study of the hardware impaired (HWI) systems highly depends on the adopted model. Recent models have proved that the aggregate noise is equivalent to improper Gaussian signals. Therefore, considering the distinct noise nature and self-interfering (SI) signals, an optimal maximum likelihood (ML) receiver is derived. This renders the conventional minimum Euclidean distance (MED) receiver as a sub-optimal receiver because it is based on the assumptions of ideal hardware transceivers and proper Gaussian noise in communication systems. Next, the average error probability performance of the proposed optimal ML receiver is analyzed and tight bounds and approximations are derived for various adopted systems including transmitter and receiver I/Q imbalanced systems with or without transmitter distortions as well as transmitter or receiver only impaired systems. Motivated by recent studies that shed the light on the benefit of improper Gaussian signaling in mitigating the HWIs, asymmetric quadrature amplitude modulation or phase shift keying is optimized and adapted for transmission. Finally, different numerical and simulation results are presented to support the superiority of the proposed ML receiver over MED receiver, the tightness of the derived bounds and effectiveness of asymmetric transmission in dampening HWIs and improving overall system performance

Mission to the Solar System: Exploration and Discovery. A Mission and Technology Roadmap

Science.gov (United States)

Gulkis, S. (Editor); Stetson, D. S. (Editor); Stofan, E. R. (Editor)

1998-01-01

Solar System exploration addresses some of humanity's most fundamental questions: How and when did life form on Earth? Does life exist elsewhere in the Solar System or in the Universe? - How did the Solar System form and evolve in time? - What can the other planets teach us about the Earth? This document describes a Mission and Technology Roadmap for addressing these and other fundamental Solar System Questions. A Roadmap Development Team of scientists, engineers, educators, and technologists worked to define the next evolutionary steps in in situ exploration, sample return, and completion of the overall Solar System survey. Guidelines were to "develop aa visionary, but affordable, mission and technology development Roadmap for the exploration of the Solar System in the 2000 to 2012 timeframe." The Roadmap provides a catalog of potential flight missions. (Supporting research and technology, ground-based observations, and laboratory research, which are no less important than flight missions, are not included in this Roadmap.)

Evaluation of full and degraded mission reliability and mission dependability for intermittently operated, multi-functional systems

International Nuclear Information System (INIS)

Sols, Alberto; Ramirez-Marquez, Jose E.; Verma, Dinesh; Vitoriano, Begona

2007-01-01

Availability is one of the metrics often used in the evaluation of system effectiveness. Its use as an effectiveness metric is often dictated by the nature of the system under consideration. While some systems operate continuously, many others operate on an intermittent basis where each operational period may often involve a different set of missions. This is the most likely scenario for complex multi-functional systems, where each specific system mission may require the availability of a different combination of system elements. Similarly, for these systems, not only is it important to know whether a mission can be initiated, it is just as important to know whether the system is capable of completing such a mission. Thus, for these systems, additional measures become relevant to provide a more holistic assessment of system effectiveness. This paper presents techniques for the evaluation of both full and degraded mission reliability and mission dependability for coherent, intermittently operated multi-functional systems. These metrics complement previously developed availability and degraded availability measures of multi-functional systems, in the comprehensive assessment of system effectiveness

Tank waste remediation system mission analysis report

International Nuclear Information System (INIS)

Acree, C.D.

1998-01-01

The Tank Waste Remediation System Mission Analysis Report identifies the initial states of the system and the desired final states of the system. The Mission Analysis Report identifies target measures of success appropriate to program-level accomplishments. It also identifies program-level requirements and major system boundaries and interfaces

Development of a prototype interactive learning system using multi-media technology for mission independent training program

Science.gov (United States)

Matson, Jack E.

1992-01-01

The Spacelab Mission Independent Training Program provides an overview of payload operations. Most of the training material is currently presented in workbook form with some lecture sessions to supplement selected topics. The goal of this project was to develop a prototype interactive learning system for one of the Mission Independent Training topics to demonstrate how the learning process can be improved by incorporating multi-media technology into an interactive system. This report documents the development process and some of the problems encountered during the analysis, design, and production phases of this system.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Turkey

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Turkey. The IUREP Orientation Phase mission to Turkey estimates that the Speculative Resources of that country fall within the range of 21 000 to 55 000 tonnes of uranium. This potential is expected to lie in areas of Neogene and possibly other Tertiary sediments, in particular in the areas of the Menderes Massif and Central Anatolia. The mission describes a proposed exploration programme with expenditures over a five year period of between $80 million and $110 million, with nearly half of the amount being spent on drilling. (author)

Linear and nonlinear optical signals in probability and phase-space representations

International Nuclear Information System (INIS)

Man'ko, Margarita A

2006-01-01

Review of different representations of signals including the phase-space representations and tomographic representations is presented. The signals under consideration are either linear or nonlinear ones. The linear signals satisfy linear quantumlike Schroedinger and von Neumann equations. Nonlinear signals satisfy nonlinear Schroedinger equations as well as Gross-Pitaevskii equation describing solitons in Bose-Einstein condensate. The Ville-Wigner distributions for solitons are considered in comparison with tomographic-probability densities describing solitons completely. different kinds of tomographies - symplectic tomography, optical tomography and Fresnel tomography are reviewed. New kind of map of the signals onto probability distributions of discrete photon number-like variable is discussed. Mutual relations between different transformations of signal functions are established in explicit form. Such characteristics of the signal-probability distribution as entropy is discussed

Intelligent mobile sensor system for drum inspection and monitoring: Phase 1

International Nuclear Information System (INIS)

1993-06-01

The objective of this project was to develop an operational system for monitoring and inspection activities for waste storage facility operations at several DOE sites. Specifically, the product of this effort is a robotic device with enhanced intelligence and maneuverability capable of conducting routine inspection of stored waste drums. The device is capable of operating in narrow aisles and interpolating the free aisle space between rows of stacked drums. The system has an integrated sensor suite for leak detection, and is interfaced with a site database both for inspection planning and for data correlation, updating, and report generation. The system is capable of departing on an assigned mission, collecting required data, recording which positions of its mission had to be aborted or modified due to environmental constraints, and reporting back when the mission is complete. Successful identification of more than 90% of all drum defects has been demonstrated in a high fidelity waste storage facility mockup. Identified anomalies included rust spots, rust streaks, areas of corrosion, dents, and tilted drums. All drums were positively identified and correlated with the site database. This development effort is separated into three phases of which phase one is now complete. The first phase has demonstrated an integrated system for monitoring and inspection activities for waste storage facility operations. This demonstration system was quickly fielded and evaluated by leveraging technologies developed from previous NASA and DARPA contracts and internal research. The second phase will demonstrate a prototype system appropriate for operational use in an actual storage facility. The prototype provides an integrated design that considers operational requirements, hardware costs, maintenance, safety, and robustness. The final phase will demonstrate commercial viability using the prototype vehicle in a pilot waste operations and inspection project

New vision solar system exploration missions study: Analysis of the use of biomodal space nuclear power systems to support outer solar system exploration missions. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-08

This report presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter mission s to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of a NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. Concepts for microspacecraft capable of probing Jupiter`s atmosphere and exploring Titan were also developed. All mission designs considered use the Atlas 2AS for launch. It is shown that the bimodal nuclear power and propulsion system offers many attractive option for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination.

Conceptual definition of a 50-100 kWe NEP system for planetary science missions

Science.gov (United States)

Friedlander, Alan

1993-01-01

The Phase 1 objective of this project is to assess the applicability of a common Nuclear Electric Propulsion (NEP) flight system of the 50-100 kWe power class to meet the advanced transportation requirements of a suite of planetary science (robotic) missions, accounting for differences in mission-specific payloads and delivery requirements. The candidate missions are as follows: (1) Comet Nucleus Sample Return; (2) Multiple Mainbelt Asteroid Rendezvous; (3) Jupiter Grand Tour (Galilean satellites and magnetosphere); (4) Uranus Orbiter/Probe (atmospheric entry and landers); (5) Neptune Orbiter/Probe (atmospheric entry and landers); and (6) Pluto-Charon Orbiter/Lander. The discussion is presented in vugraph form.

Inertial Navigation System for India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD HEX) Mission

Science.gov (United States)

Umadevi, P.; Navas, A.; Karuturi, Kesavabrahmaji; Shukkoor, A. Abdul; Kumar, J. Krishna; Sreekumar, Sreejith; Basim, A. Mohammed

2017-12-01

This work presents the configuration of Inertial Navigation System (INS) used in India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) Program. In view of the specific features and requirements of the RLV-TD, specific improvements and modifications were required in the INS. A new system was designed, realised and qualified meeting the mission requirements of RLV-TD, at the same time taking advantage of the flight heritage attained in INS through various Launch vehicle Missions of the country. The new system has additional redundancy in acceleration channel, in-built inclinometer based bias update scheme for acceleration channels and sign conventions as employed in an aircraft. Data acquisition in micro cycle periodicity (10 ms) was incorporated which was required to provide rate and attitude information at higher sampling rate for ascent phase control. Provision was incorporated for acquisition of rate and acceleration data with high resolution for aerodynamic characterisation and parameter estimation. GPS aided navigation scheme was incorporated to meet the stringent accuracy requirements of the mission. Navigation system configuration for RLV-TD, specific features incorporated to meet the mission requirements, various tests carried out and performance during RLV-TD flight are highlighted.

Multi-Mission SDR, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Wireless transceivers used for NASA space missions have traditionally been highly custom and mission specific. Programs such as the GRC Space Transceiver Radio...

Markov transition probability-based network from time series for characterizing experimental two-phase flow

International Nuclear Information System (INIS)

Gao Zhong-Ke; Hu Li-Dan; Jin Ning-De

2013-01-01

We generate a directed weighted complex network by a method based on Markov transition probability to represent an experimental two-phase flow. We first systematically carry out gas—liquid two-phase flow experiments for measuring the time series of flow signals. Then we construct directed weighted complex networks from various time series in terms of a network generation method based on Markov transition probability. We find that the generated network inherits the main features of the time series in the network structure. In particular, the networks from time series with different dynamics exhibit distinct topological properties. Finally, we construct two-phase flow directed weighted networks from experimental signals and associate the dynamic behavior of gas-liquid two-phase flow with the topological statistics of the generated networks. The results suggest that the topological statistics of two-phase flow networks allow quantitative characterization of the dynamic flow behavior in the transitions among different gas—liquid flow patterns. (general)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Burundi

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Burundi. The IUREP Orientation Phase Mission to Burundi estimates that the Speculative Resources of that country fall within the range of 300 to more than 4 100 tonnes of uranium. The potential is rather evenly distributed throughout the Proterozoic of Burundi in various geological environments (unconformity, hydrothermal, fault controlled, etc.). The mission recommends that over a period of five years U.S. $ 3 to 4.5 million be spent on exploration in Burundi, with even spending on the various exploration techniques as e.g. prospecting, drilling trenching, geophysical surveys, analyses, etc. (author)

Collaboration support system for "Phobos-Soil" space mission.

Science.gov (United States)

Nazarov, V.; Nazirov, R.; Zakharov, A.

2009-04-01

Rapid development of communication facilities leads growth of interactions done via electronic means. However we can see some paradox in this segment in last times: Extending of communication facilities increases collaboration chaos. And it is very sensitive for space missions in general and scientific space mission particularly because effective decision of this task provides successful realization of the missions and promises increasing the ratio of functional characteristic and cost of mission at all. Resolving of this problem may be found by using respective modern technologies and methods which widely used in different branches and not in the space researches only. Such approaches as Social Networking, Web 2.0 and Enterprise 2.0 look most prospective in this context. The primary goal of the "Phobos-Soil" mission is an investigation of the Phobos which is the Martian moon and particularly its regolith, internal structure, peculiarities of the orbital and proper motion, as well as a number of different scientific measurements and experiments for investigation of the Martian environment. A lot of investigators involved in the mission. Effective collaboration system is key facility for information support of the mission therefore. Further to main goal: communication between users of the system, modern approaches allows using such capabilities as self-organizing community, user generated content, centralized and federative control of the system. Also it may have one unique possibility - knowledge management which is very important for space mission realization. Therefore collaboration support system for "Phobos-Soil" mission designed on the base of multilayer model which includes such levels as Communications, Announcement and Information, Data sharing and Knowledge management. The collaboration support system for "Phobos-Soil" mission will be used as prototype for prospective Russian scientific space missions and the presentation describes its architecture

LISA Mission and System architectures and performances

International Nuclear Information System (INIS)

Gath, Peter F; Weise, Dennis; Schulte, Hans-Reiner; Johann, Ulrich

2009-01-01

In the context of the LISA Mission Formulation Study, the LISA System was studied in detail and a new baseline architecture for the whole mission was established. This new baseline is the result of trade-offs on both, mission and system level. The paper gives an overview of the different mission scenarios and configurations that were studied in connection with their corresponding advantages and disadvantages as well as performance estimates. Differences in the required technologies and their influence on the overall performance budgets are highlighted for all configurations. For the selected baseline concept, a more detailed description of the configuration is given and open issues in the technologies involved are discussed.

LISA Mission and System architectures and performances

Energy Technology Data Exchange (ETDEWEB)

Gath, Peter F; Weise, Dennis; Schulte, Hans-Reiner; Johann, Ulrich, E-mail: peter.gath@astrium.eads.ne [Astrium GmbH Satellites, 88039 Friedrichshafen (Germany)

2009-03-01

In the context of the LISA Mission Formulation Study, the LISA System was studied in detail and a new baseline architecture for the whole mission was established. This new baseline is the result of trade-offs on both, mission and system level. The paper gives an overview of the different mission scenarios and configurations that were studied in connection with their corresponding advantages and disadvantages as well as performance estimates. Differences in the required technologies and their influence on the overall performance budgets are highlighted for all configurations. For the selected baseline concept, a more detailed description of the configuration is given and open issues in the technologies involved are discussed.

Propagating Mixed Uncertainties in Cyber Attacker Payoffs: Exploration of Two-Phase Monte Carlo Sampling and Probability Bounds Analysis

Energy Technology Data Exchange (ETDEWEB)

Chatterjee, Samrat; Tipireddy, Ramakrishna; Oster, Matthew R.; Halappanavar, Mahantesh

2016-09-16

Securing cyber-systems on a continual basis against a multitude of adverse events is a challenging undertaking. Game-theoretic approaches, that model actions of strategic decision-makers, are increasingly being applied to address cybersecurity resource allocation challenges. Such game-based models account for multiple player actions and represent cyber attacker payoffs mostly as point utility estimates. Since a cyber-attacker’s payoff generation mechanism is largely unknown, appropriate representation and propagation of uncertainty is a critical task. In this paper we expand on prior work and focus on operationalizing the probabilistic uncertainty quantification framework, for a notional cyber system, through: 1) representation of uncertain attacker and system-related modeling variables as probability distributions and mathematical intervals, and 2) exploration of uncertainty propagation techniques including two-phase Monte Carlo sampling and probability bounds analysis.

A Risk-Constrained Multi-Stage Decision Making Approach to the Architectural Analysis of Mars Missions

Science.gov (United States)

Kuwata, Yoshiaki; Pavone, Marco; Balaram, J. (Bob)

2012-01-01

This paper presents a novel risk-constrained multi-stage decision making approach to the architectural analysis of planetary rover missions. In particular, focusing on a 2018 Mars rover concept, which was considered as part of a potential Mars Sample Return campaign, we model the entry, descent, and landing (EDL) phase and the rover traverse phase as four sequential decision-making stages. The problem is to find a sequence of divert and driving maneuvers so that the rover drive is minimized and the probability of a mission failure (e.g., due to a failed landing) is below a user specified bound. By solving this problem for several different values of the model parameters (e.g., divert authority), this approach enables rigorous, accurate and systematic trade-offs for the EDL system vs. the mobility system, and, more in general, cross-domain trade-offs for the different phases of a space mission. The overall optimization problem can be seen as a chance-constrained dynamic programming problem, with the additional complexity that 1) in some stages the disturbances do not have any probabilistic characterization, and 2) the state space is extremely large (i.e, hundreds of millions of states for trade-offs with high-resolution Martian maps). To this purpose, we solve the problem by performing an unconventional combination of average and minimax cost analysis and by leveraging high efficient computation tools from the image processing community. Preliminary trade-off results are presented.

Hybrid rocket propulsion systems for outer planet exploration missions

Science.gov (United States)

Jens, Elizabeth T.; Cantwell, Brian J.; Hubbard, G. Scott

2016-11-01

Outer planet exploration missions require significant propulsive capability, particularly to achieve orbit insertion. Missions to explore the moons of outer planets place even more demanding requirements on propulsion systems, since they involve multiple large ΔV maneuvers. Hybrid rockets present a favorable alternative to conventional propulsion systems for many of these missions. They typically enjoy higher specific impulse than solids, can be throttled, stopped/restarted, and have more flexibility in their packaging configuration. Hybrids are more compact and easier to throttle than liquids and have similar performance levels. In order to investigate the suitability of these propulsion systems for exploration missions, this paper presents novel hybrid motor designs for two interplanetary missions. Hybrid propulsion systems for missions to Europa and Uranus are presented and compared to conventional in-space propulsion systems. The hybrid motor design for each of these missions is optimized across a range of parameters, including propellant selection, O/F ratio, nozzle area ratio, and chamber pressure. Details of the design process are described in order to provide guidance for researchers wishing to evaluate hybrid rocket motor designs for other missions and applications.

Generic procedure for designing and implementing plan management systems for space science missions operations

Science.gov (United States)

Chaizy, P. A.; Dimbylow, T. G.; Allan, P. M.; Hapgood, M. A.

2011-09-01

This paper is one of the components of a larger framework of activities whose purpose is to improve the performance and productivity of space mission systems, i.e. to increase both what can be achieved and the cost effectiveness of this achievement. Some of these activities introduced the concept of Functional Architecture Module (FAM); FAMs are basic blocks used to build the functional architecture of Plan Management Systems (PMS). They also highlighted the need to involve Science Operations Planning Expertise (SOPE) during the Mission Design Phase (MDP) in order to design and implement efficiently operation planning systems. We define SOPE as the expertise held by people who have both theoretical and practical experience in operations planning, in general, and in space science operations planning in particular. Using ESA's methodology for studying and selecting science missions we also define the MDP as the combination of the Mission Assessment and Mission Definition Phases. However, there is no generic procedure on how to use FAMs efficiently and systematically, for each new mission, in order to analyse the cost and feasibility of new missions as well as to optimise the functional design of new PMS; the purpose of such a procedure is to build more rapidly and cheaply such PMS as well as to make the latter more reliable and cheaper to run. This is why the purpose of this paper is to provide an embryo of such a generic procedure and to show that the latter needs to be applied by people with SOPE during the MDP. The procedure described here proposes some initial guidelines to identify both the various possible high level functional scenarii, for a given set of possible requirements, and the information that needs to be associated with each scenario. It also introduces the concept of catalogue of generic functional scenarii of PMS for space science missions. The information associated with each catalogued scenarii will have been identified by the above procedure and

PDE-Foam - a probability-density estimation method using self-adapting phase-space binning

CERN Document Server

Dannheim, Dominik; Voigt, Alexander; Grahn, Karl-Johan; Speckmayer, Peter

2009-01-01

Probability-Density Estimation (PDE) is a multivariate discrimination technique based on sampling signal and background densities defined by event samples from data or Monte-Carlo (MC) simulations in a multi-dimensional phase space. To efficiently use large event samples to estimate the probability density, a binary search tree (range searching) is used in the PDE-RS implementation. It is a generalisation of standard likelihood methods and a powerful classification tool for problems with highly non-linearly correlated observables. In this paper, we present an innovative improvement of the PDE method that uses a self-adapting binning method to divide the multi-dimensional phase space in a finite number of hyper-rectangles (cells). The binning algorithm adjusts the size and position of a predefined number of cells inside the multidimensional phase space, minimizing the variance of the signal and background densities inside the cells. The binned density information is stored in binary trees, allowing for a very ...

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Somalia

International Nuclear Information System (INIS)

Levich, Robert A.; Muller-Kahle, Eberhard

1983-04-01

The IUREP Orientation Phase Mission to Somalia suggests that in addition to the reasonably assured resources (RAR) of 5 000 t uranium and estimated additional resources (EAR) of 11 000 t uranium in calcrete deposits, the speculative resources (SR) could be within the wide range of 0 - 150 000 t uranium. The majority of these speculative resources are related to sandstone and calcrete deposits. The potential for magmatic hydrothermal deposits is relatively small. The Mission recommends an exploration programme of about US $ 22 000 000 to test the uranium potential of the country which is thought to be excellent. The Mission also suggests a reorganization of the Somalia Geological Survey in order to improve its efficiency. Recommended methods include geological mapping, Landsat Imagery Interpretation, airborne and ground scintillometer surveys, and geochemistry. Follow-up radiometric surveys, exploration geophysics, mineralogical studies, trenching and drilling are proposed in favourable areas

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Uganda

International Nuclear Information System (INIS)

1985-01-01

A full report has been compiled describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Uganda. The Mission suggest that the speculative uranium resources of the country could be within the very wide range of 0 to 105 000 tonnes of uranium metal. The Mission finds that most of these speculative resources are related to Proterozoic unconformities and to Cenozoic sandstones of the Western Rift Valley. Some potential is also associated with Post-tectonic granites. The Mission recommends to rehabilitate the Geological Survey of Uganda in order to enable it to conduct and support a uranium exploration programme for unconformity related and for standstone hosted uranium deposits. Recommended exploration methods encompass geological mapping and compilation, an airborne gamma-ray spectrometer survey north of 1 deg. North latitude, stream sediment sampling, and ground scintillometric surveys in favourable areas. Follow up work should include VLF-EM surveys, emanometry and drilling. (author)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Somalia

International Nuclear Information System (INIS)

1985-01-01

A full report has been compiled describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Somalia. The Mission suggests that in addition to the reasonably assured resources (RAR) of 5 000 t uranium and estimated additional resources (EAR) of 11 000 t uranium in calcrete deposits, the speculative resources (SR) could be within the wide range of 0 - 150 000 t uranium. The majority of these speculative resources are related to sandstone and calcrete deposits. The potential for magmatic hydrothermal deposits is relatively small. The Mission recommends an exploration programme of about US$ 22 000 000 to test the uranium potential of the country which is thought to be excellent. The Mission also suggests a reorganization of the Somalia Geological Survey in order to improve its efficiency. Recommended methods include geological mapping, Landsat imagery interpretation, airborne and ground scintillometer surveys, and geochemistry. Follow-up radiometric surveys, exploration geophysics, mineralogical studies, trenching and drilling are proposed in favourable areas. (author)

Power system technologies for the manned Mars mission

International Nuclear Information System (INIS)

Bents, D.; Patterson, M.J.; Berkopec, F.; Myers, I.; Presler, A.

1986-01-01

The high impulse of electric propulsion makes it an attractive option for manned interplanetary missions such as a manned mission to Mars. This option is, however, dependent on the availability of high energy sources for propulsive power in addition to that required for the manned interplanetary transit vehicle. Two power system technologies are presented: nuclear and solar. The ion thruster technology for the interplanetary transit vehicle is described for a typical mission. The power management and distribution system components required for such a mission must be further developed beyond today's technology status. High voltage-high current technology advancements must be achieved. These advancements are described. In addition, large amounts of waste heat must be rejected to the space environment by the thermal management system. Advanced concepts such as the liquid droplet radiator are discussed as possible candidates for the manned Mars mission. These thermal management technologies have great potential for significant weight reductions over the more conventional systems

The SOFIA Mission Control System Software

Science.gov (United States)

Heiligman, G. M.; Brock, D. R.; Culp, S. D.; Decker, P. H.; Estrada, J. C.; Graybeal, J. B.; Nichols, D. M.; Paluzzi, P. R.; Sharer, P. J.; Pampell, R. J.; Papke, B. L.; Salovich, R. D.; Schlappe, S. B.; Spriestersbach, K. K.; Webb, G. L.

1999-05-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) will be delivered with a computerized mission control system (MCS). The MCS communicates with the aircraft's flight management system and coordinates the operations of the telescope assembly, mission-specific subsystems, and the science instruments. The software for the MCS must be reliable and flexible. It must be easily usable by many teams of observers with widely differing needs, and it must support non-intrusive access for education and public outreach. The technology must be appropriate for SOFIA's 20-year lifetime. The MCS software development process is an object-oriented, use case driven approach. The process is iterative: delivery will be phased over four "builds"; each build will be the result of many iterations; and each iteration will include analysis, design, implementation, and test activities. The team is geographically distributed, coordinating its work via Web pages, teleconferences, T.120 remote collaboration, and CVS (for Internet-enabled configuration management). The MCS software architectural design is derived in part from other observatories' experience. Some important features of the MCS are: * distributed computing over several UNIX and VxWorks computers * fast throughput of time-critical data * use of third-party components, such as the Adaptive Communications Environment (ACE) and the Common Object Request Broker Architecture (CORBA) * extensive configurability via stored, editable configuration files * use of several computer languages so developers have "the right tool for the job". C++, Java, scripting languages, Interactive Data Language (from Research Systems, Int'l.), XML, and HTML will all be used in the final deliverables. This paper reports on work in progress, with the final product scheduled for delivery in 2001. This work was performed for Universities Space Research Association for NASA under contract NAS2-97001.

Application of a Reliability Model Generator to a Pressure Tank System

Institute of Scientific and Technical Information of China (English)

Kathryn Stockwell; Sarah Dunnett

2013-01-01

A number of mathematical modelling techniques exist which are used to measure the performance of a given system,by assessing each individual component within the system.This can be used to determine the failure frequency or probability of the system.Software is available to undertake the task of analysing these mathematical models after an individual or group of individuals manually create the models.The process of generating these models is time consuming and reduces the impact of the model on the system design.One way to improve this would be to generate the model automatically.In this work,the procedure to automatically construct a model,based on Petri nets,for systems undergoing a phased-mission is applied to a pressure tank system,undertaking a four phase mission.

Phase flow and statistical structure of Galton-board systems

International Nuclear Information System (INIS)

Lue, A.; Brenner, H.

1993-01-01

Galton boards, found in museum exhibits devoted to science and technology, are often used to demonstrate visually the ubiquity of so-called ''laws of probability'' via an experimental realization of normal distributions. A detailed theoretical study of Galton-board phase-space dynamics and statistical behavior is presented. The study is based on a simple inelastic-collision model employing a particle fall- ing through a spatially periodic lattice of rigid, convex scatterers. We show that such systems exhibit indeterminate behavior through the presence of strange attractors or strange repellers in phase space; nevertheless, we also show that these systems exhibit regular and predictable behavior under specific circumstances. Phase-space strange attractors, periodic attractors, and strange repellers are present in numerical simulations, confirming results anticipated from geometric analysis. The system's geometry (dictated by lattice geometry and density as well as the direction of gravity) is observed to play a dominant role in stability, phase-flow topology, and statistical observations. Smale horseshoes appear to exist in the low-lattice-density limit and may exist in other regimes. These horseshoes are generated by homoclinic orbits whose existence is dictated by system characteristics. The horseshoes lead directly to deterministic chaos in the system. Strong evidence exists for ergodicity in all attractors. Phase-space complexities are manifested at all observed levels, particularly statistical ones. Consequently, statistical observations are critically dependent upon system details. Under well-defined circumstances, these observations display behavior which does not constitute a realization of the ''laws of probability.''

Mission reliability of semi-Markov systems under generalized operational time requirements

International Nuclear Information System (INIS)

Wu, Xiaoyue; Hillston, Jane

2015-01-01

Mission reliability of a system depends on specific criteria for mission success. To evaluate the mission reliability of some mission systems that do not need to work normally for the whole mission time, two types of mission reliability for such systems are studied. The first type corresponds to the mission requirement that the system must remain operational continuously for a minimum time within the given mission time interval, while the second corresponds to the mission requirement that the total operational time of the system within the mission time window must be greater than a given value. Based on Markov renewal properties, matrix integral equations are derived for semi-Markov systems. Numerical algorithms and a simulation procedure are provided for both types of mission reliability. Two examples are used for illustration purposes. One is a one-unit repairable Markov system, and the other is a cold standby semi-Markov system consisting of two components. By the proposed approaches, the mission reliability of systems with time redundancy can be more precisely estimated to avoid possible unnecessary redundancy of system resources. - Highlights: • Two types of mission reliability under generalized requirements are defined. • Equations for both types of reliability are derived for semi-Markov systems. • Numerical methods are given for solving both types of reliability. • Simulation procedure is given for estimating both types of reliability. • Verification of the numerical methods is given by the results of simulation

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Ghana. Draft

International Nuclear Information System (INIS)

Guelpa, Jean-Paul; Vogel, Wolfram

1982-12-01

The Republic of Ghana has no claimed uranium resources in the categories Reasonably Assured and Estimated Additional. The only occurrences known are within pegmatites and are of no economic importance. The IUREP Orientation Phase Mission to Ghana estimates that the Speculative Resources of the country fall between 15,000 and 40,000 tonnes uranium. The IUREP Orientation Phase Mission to Ghana believes that the Panafrican Mobile Belt has the highest uranium potential of all geological units of the country. The Obosum beds are the priority number two target. A three years exploration programme is recommended for a total cost of US $ 5,000,000. The Ghana Atomic Energy Commission and the Ghana Geological Survey provide a basic infrastructure for uranium exploration. Any future uranium development in Ghana should be embedded in a well defined national uranium policy. It is recommended that such a policy be draw, up by the Ghanaian authorities

Mission profile based multi-disciplinary analysis of power modules in single-phase transformerless photovoltaic inverters

DEFF Research Database (Denmark)

Yang, Yongheng; Wang, Huai; Blaabjerg, Frede

2013-01-01

years) has been set as a main target and an emerging demand from the customers, which imposes a new challenge on grid-connected transformerless inverters. In order to reduce maintenance cost, it is essential to predict the lifetime of the transformerless PV inverter and its components based......The popularity of transformerless photovoltaic (PV) inverters in Europe proves that these topologies can achieve higher efficiency (e.g., ≥ 98% has been reported). Along with the advanced power electronics technology and the booming development of PV power systems, a long service time (e.g. 25...... on the mission profiles — solar irradiance and ambient temperature. In this paper, a mission profile based analysis approach is proposed and it is demonstrated by three main single-phase transformerless PV inverters — Full-Bridge (FB) with bipolar modulation scheme, the FB inverter with DC bypass (FB...

A note on iterated function systems with discontinuous probabilities

International Nuclear Information System (INIS)

Jaroszewska, Joanna

2013-01-01

Highlights: ► Certain iterated function system with discontinuous probabilities is discussed. ► Existence of an invariant measure via the Schauder–Tychonov theorem is established. ► Asymptotic stability of the system under examination is proved. -- Abstract: We consider an example of an iterated function system with discontinuous probabilities. We prove that it posses an invariant probability measure. We also prove that it is asymptotically stable provided probabilities are positive

Probability of satellite collision

Science.gov (United States)

Mccarter, J. W.

1972-01-01

A method is presented for computing the probability of a collision between a particular artificial earth satellite and any one of the total population of earth satellites. The collision hazard incurred by the proposed modular Space Station is assessed using the technique presented. The results of a parametric study to determine what type of satellite orbits produce the greatest contribution to the total collision probability are presented. Collision probability for the Space Station is given as a function of Space Station altitude and inclination. Collision probability was also parameterized over miss distance and mission duration.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Venezuela

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Venezuela. The IUREP Orientation Phase mission to Venezuela estimates that the Speculative Resources of that country fall within the range 2,000 to 42,000 tonnes uranium.- The majority of this potential is expected to be located in the Precambrian crystalline and sedimentary rocks of the Guayana Shield. Other potentially favorable geologic environments include Cretaceous phosphorite beds, continental sandstone and granitic rocks. The mission recommends that approximately US $18 million be spent on exploration in Venezuela over the next five years. The majority of this expenditure would be for surface surveys utilizing geologic studies, radiometric and geochemical surveys and some drilling for geologic information. Additional drilling would be required later to substantiate preliminary findings. (author)

Medical Operations Decision Support System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Determining the probability of specific medical events on a given space mission is difficult. Yet, it is important to have reasonable estimates of these...

Tank waste remediation system retrieval and disposal mission readiness-to-proceed memorandum

International Nuclear Information System (INIS)

Jordan, K.N.

1998-01-01

This memorandum provides a summary of PHMC (Project Hanford Management Contract) team work scope for the Phase 1 TWRS Retrieval and Disposal Mission, a declaration of readiness-to proceed, a summary of the PHMC readiness evaluation process, summary results of a structured independent appraisal and financial analysis including information associated with assumptions, risks, and recommendations and, a summary of program plans for the PHMC team's component of the Phase 1 Mission

Summary Report on Phase I and Phase II Results From the 3D Printing in Zero-G Technology Demonstration Mission. Volume II

Science.gov (United States)

Prater, T. J.; Werkheiser, N. J.; Ledbetter, F. E., III

2018-01-01

In-space manufacturing seeks to develop the processes, skill sets, and certification architecture needed to provide a rapid response manufacturing capability on long-duration exploration missions. The first 3D printer on the Space Station was developed by Made in Space, Inc. and completed two rounds of operation on orbit as part of the 3D Printing in Zero-G Technology Demonstration Mission. This Technical Publication provides a comprehensive overview of the technical objections of the mission, the two phases of hardware operation conducted on orbit, and the subsequent detailed analysis of specimens produced. No engineering significant evidence of microgravity effects on material outcomes was noted. This technology demonstration mission represents the first step in developing a suite of manufacturing capabilities to meet future mission needs.

Applications of nuclear reactor power systems to electric propulsion missions.

Science.gov (United States)

Schaupp, R. W.; Sawyer, C. D.

1971-01-01

The performance of nuclear electric propulsion systems (NEP) has been evaluated for a wide variety of missions in an attempt to establish the commonality of NEP system requirements. Emphasis was given to those requirements and system characteristics that serve as guidelines for current technology development programs. Various interactions and tradeoffs between NEP system and mission parameters are described. The results show that the most significant factors in selecting NEP system size are launch mode (direct or spiral escape) and, to a weaker extent, launch vehicle capability. Other factors such as mission, payload, and thrust time constraints, have little influence, thus allowing one NEP system to be used for many missions. The results indicated that a 100 kWe NEP would be suitable for most direct escape missions and a 250 kWe NEP system would be suitable for more demanding missions that use the spiral escape mode.

Modeling and Simulation for Mission Operations Work System Design

Science.gov (United States)

Sierhuis, Maarten; Clancey, William J.; Seah, Chin; Trimble, Jay P.; Sims, Michael H.

2003-01-01

Work System analysis and design is complex and non-deterministic. In this paper we describe Brahms, a multiagent modeling and simulation environment for designing complex interactions in human-machine systems. Brahms was originally conceived as a business process design tool that simulates work practices, including social systems of work. We describe our modeling and simulation method for mission operations work systems design, based on a research case study in which we used Brahms to design mission operations for a proposed discovery mission to the Moon. We then describe the results of an actual method application project-the Brahms Mars Exploration Rover. Space mission operations are similar to operations of traditional organizations; we show that the application of Brahms for space mission operations design is relevant and transferable to other types of business processes in organizations.

Centralized mission planning and scheduling system for the Landsat Data Continuity Mission

Science.gov (United States)

Kavelaars, Alicia; Barnoy, Assaf M.; Gregory, Shawna; Garcia, Gonzalo; Talon, Cesar; Greer, Gregory; Williams, Jason; Dulski, Vicki

2014-01-01

Satellites in Low Earth Orbit provide missions with closer range for studying aspects such as geography and topography, but often require efficient utilization of space and ground assets. Optimizing schedules for these satellites amounts to a complex planning puzzle since it requires operators to face issues such as discontinuous ground contacts, limited onboard memory storage, constrained downlink margin, and shared ground antenna resources. To solve this issue for the Landsat Data Continuity Mission (LDCM, Landsat 8), all the scheduling exchanges for science data request, ground/space station contact, and spacecraft maintenance and control will be coordinated through a centralized Mission Planning and Scheduling (MPS) engine, based upon GMV’s scheduling system flexplan9 . The synchronization between all operational functions must be strictly maintained to ensure efficient mission utilization of ground and spacecraft activities while working within the bounds of the space and ground resources, such as Solid State Recorder (SSR) and available antennas. This paper outlines the functionalities that the centralized planning and scheduling system has in its operational control and management of the Landsat 8 spacecraft.

Tank waste remediation system retrieval and disposal mission readiness-to-proceed memorandum

International Nuclear Information System (INIS)

Boston, H.L.

1998-01-01

This memorandum provides a summary of PHMC [Project Hanford Management Contract] team work scope for the Phase 1 TWRS Retrieval and Disposal Mission, a declaration of readiness-to-proceed, a summary of the PHMC team readiness evaluation process, summary results of a structured independent appraisal and financial analysis including information associated with assumptions, risks, and recommendations and, a summary of program plans for the PHMC team's component of the Phase 1 Mission

Tank waste remediation system retrieval and disposal mission readiness-to-proceed memorandum

Energy Technology Data Exchange (ETDEWEB)

Boston, H.L.

1998-01-07

This memorandum provides a summary of PHMC [Project Hanford Management Contract] team work scope for the Phase 1 TWRS Retrieval and Disposal Mission, a declaration of readiness-to-proceed, a summary of the PHMC team readiness evaluation process, summary results of a structured independent appraisal and financial analysis including information associated with assumptions, risks, and recommendations and, a summary of program plans for the PHMC team`s component of the Phase 1 Mission.

CEO Sites Mission Management System (SMMS)

Science.gov (United States)

Trenchard, Mike

2014-01-01

Late in fiscal year 2011, the Crew Earth Observations (CEO) team was tasked to upgrade its science site database management tool, which at the time was integrated with the Automated Mission Planning System (AMPS) originally developed for Earth Observations mission planning in the 1980s. Although AMPS had been adapted and was reliably used by CEO for International Space Station (ISS) payload operations support, the database structure was dated, and the compiler required for modifications would not be supported in the Windows 7 64-bit operating system scheduled for implementation the following year. The Sites Mission Management System (SMMS) is now the tool used by CEO to manage a heritage Structured Query Language (SQL) database of more than 2,000 records for Earth science sites. SMMS is a carefully designed and crafted in-house software package with complete and detailed help files available for the user and meticulous internal documentation for future modifications. It was delivered in February 2012 for test and evaluation. Following acceptance, it was implemented for CEO mission operations support in April 2012. The database spans the period from the earliest systematic requests for astronaut photography during the shuttle era to current ISS mission support of the CEO science payload. Besides logging basic image information (site names, locations, broad application categories, and mission requests), the upgraded database management tool now tracks dates of creation, modification, and activation; imagery acquired in response to requests; the status and location of ancillary site information; and affiliations with studies, their sponsors, and collaborators. SMMS was designed to facilitate overall mission planning in terms of site selection and activation and provide the necessary site parameters for the Satellite Tool Kit (STK) Integrated Message Production List Editor (SIMPLE), which is used by CEO operations to perform daily ISS mission planning. The CEO team

Electrical Power System Architectures for In-House NASA/GSFC Missions

Science.gov (United States)

Yun, Diane D.

2006-01-01

This power point presentation reviews the electrical power system (EPS) architecture used for a few NASA GSFC's missions both current and planned. Included in the presentation are reviews of electric power systems for the Space Technology 5 (ST5) mission, the Solar Dynamics Observatory (SDO) Mission, and the Lunar Reconnaissance Orbiter (LRO). There is a slide that compares the three missions' electrical supply systems.

A Saturn Ring Observer Mission Using Multi-Mission Radioisotope Power Systems

International Nuclear Information System (INIS)

Abelson, Robert D.; Spilker, Thomas R.; Shirley, James H.

2006-01-01

Saturn remains one of the most fascinating planets within the solar system. To better understand the complex ring structure of this planet, a conceptual Saturn Ring Observer (SRO) mission is presented that would spend one year in close proximity to Saturn's A and B rings, and perform detailed observations and measurements of the ring particles and electric and magnetic fields. The primary objective of the mission would be to understand ring dynamics, including the microphysics of individual particles and small scale (meters to a few kilometers) phenomena such as particle agglomeration behavior. This would be accomplished by multispectral imaging of the rings at multiple key locations within the A and B rings, and by ring-particle imaging at an unprecedented resolution of 0.5 cm/pixel. The SRO spacecraft would use a Venus-Earth-Earth-Jupiter Gravity Assist (VEEJGA) and be aerocaptured into Saturn orbit using an advanced aeroshell design to minimize propellant mass. Once in orbit, the SRO would stand off from the ring plane 1 to 1.4 km using chemical thrusters to provide short propulsive maneuvers four times per revolution, effectively causing the SRO vehicle to 'hop' above the ring plane. The conceptual SRO spacecraft would be enabled by the use of a new generation of multi-mission Radioisotope Power Systems (RPSs) currently being developed by NASA and DOE. These RPSs include the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) and Stirling Radioisotope Generator (SRG). The RPSs would generate all necessary electrical power (≥330 We at beginning of life) during the 10-year cruise and 1-year science mission (∼11 years total). The RPS heat would be used to maintain the vehicle's operating and survival temperatures, minimizing the need for electrical heaters. Such a mission could potentially launch in the 2015-2020 timeframe, with operations at Saturn commencing in approximately 2030

Development of phased mission analysis program with Monte Carlo method. Improvement of the variance reduction technique with biasing towards top event

International Nuclear Information System (INIS)

Yang Jinan; Mihara, Takatsugu

1998-12-01

This report presents a variance reduction technique to estimate the reliability and availability of highly complex systems during phased mission time using the Monte Carlo simulation. In this study, we introduced the variance reduction technique with a concept of distance between the present system state and the cut set configurations. Using this technique, it becomes possible to bias the transition from the operating states to the failed states of components towards the closest cut set. Therefore a component failure can drive the system towards a cut set configuration more effectively. JNC developed the PHAMMON (Phased Mission Analysis Program with Monte Carlo Method) code which involved the two kinds of variance reduction techniques: (1) forced transition, and (2) failure biasing. However, these techniques did not guarantee an effective reduction in variance. For further improvement, a variance reduction technique incorporating the distance concept was introduced to the PHAMMON code and the numerical calculation was carried out for the different design cases of decay heat removal system in a large fast breeder reactor. Our results indicate that the technique addition of this incorporating distance concept is an effective means of further reducing the variance. (author)

Balancing burn-in and mission times in environments with catastrophic and repairable failures

International Nuclear Information System (INIS)

Bebbington, Mark; Lai, C.-D.; Zitikis, Ricardas

2009-01-01

In a system subject to both repairable and catastrophic (i.e., nonrepairable) failures, 'mission success' can be defined as operating for a specified time without a catastrophic failure. We examine the effect of a burn-in process of duration τ on the mission time x, and also on the probability of mission success, by introducing several functions and surfaces on the (τ,x)-plane whose extrema represent suitable choices for the best burn-in time, and the best burn-in time for a desired mission time. The corresponding curvature functions and surfaces provide information about probabilities and expectations related to these burn-in and mission times. Theoretical considerations are illustrated with both parametric and, separating the failures by failure mode, nonparametric analyses of a data set, and graphical visualization of results.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Rwanda

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Rwanda. The IUREP Orientation Phase Mission to Rwanda estimates that the Speculative Resources of that country fall within the range of 500 to 5 000 tonnes of uranium. The majority of this potential is expected to be located in the Precambrian Ruzizian, especially in conjunction with tectonized pegmatoidal remobilizations of metamorphic sediments of western Rwanda. Other favourable geological environments include lamprophyric dikes and post tectonic granites of central Rwanda. The Mission recommends that over a period of five years approximately US$4.2 million be spent on exploration in Rwanda. The majority of this would be spent on airborne and ground geophysical surveys ($1.5 million) and exploration drilling ($1 million). Prospecting, trenching and tunneling and analytical work would require the remainder of the $4.2 million ($1.7 million). (author)

Pre-Launch Phase 1 Calibration and Validation Rehearsal of Geophysical Data Products of Soil Moisture Active Passive (SMAP) Mission

Science.gov (United States)

Colliander, A.; Jackson, T. J.; Chan, S.; Dunbar, R.; Das, N. N.; Kim, S.; Reichle, R. H.; De Lannoy, G. J.; Liu, Q.; Kimball, J. S.; Yi, Y.; Cosh, M. H.; Bindlish, R.; Crow, W. T.; Dang, L.; Yueh, S. H.; Njoku, E. G.

2013-12-01

NASA's Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in October 2014. The objective of the mission is global mapping of soil moisture and freeze/thaw state. SMAP utilizes an L-band radar and radiometer sharing a rotating 6-meter mesh reflector antenna. The instruments will operate onboard the SMAP spacecraft in a 685-km Sun-synchronous near-polar orbit, viewing the surface at a constant 40-degree incidence angle with a 1000-km swath width. Merging of active and passive L-band observations of the mission will enable an unprecedented combination of accuracy, resolution, coverage and revisit-time for soil moisture and freeze/thaw state retrieval. SMAP measurements will enable significantly improved estimates of water, energy and carbon transfers between the land and atmosphere. The SMAP science data product suite of geophysical parameters will include estimates of surface (top 5 cm) and root-zone (down to 1-m depth) soil moisture, net ecosystem exchange, and classification of the frozen/non-frozen state of the landscape. The primary validation reference of the data products will be ground-based measurements. Other remote sensing and model-based products will be used as additional resources. The post-launch timeline of the mission requires that the geophysical data products are validated (with respect to the mission requirements) within 12 months after a 3-month in-orbit check-out phase. SMAP is taking several preparatory steps in order to meet this schedule. One of the main steps consists of running a rehearsal to exercise calibration and validation procedures planned for the Cal/Val Phase. The rehearsal is divided into two stages. Phase 1, which was conducted in June-August 2013, focused on validation methodologies for the geophysical data products. Phase 2, which will be conducted in May-June 2014, includes operational aspects including a fully functioning SMAP Science Data System. (Note that the rehearsals do not include an airborne field

Solar-Electrochemical Power System for a Mars Mission

Science.gov (United States)

Withrow, Colleen A.; Morales, Nelson

1994-01-01

This report documents a sizing study of a variety of solar electrochemical power systems for the intercenter NASA study known as 'Mars Exploration Reference Mission'. Power systems are characterized for a variety of rovers, habitation modules, and space transport vehicles based on requirements derived from the reference mission. The mission features a six-person crew living on Mars for 500 days. Mission power requirements range from 4 kWe to 120 kWe. Primary hydrogen and oxygen fuel cells, regenerative hydrogen and oxygen fuel cells, sodium sulfur batteries advanced photovoltaic solar arrays of gallium arsenide on germanium with tracking and nontracking mechanisms, and tent solar arrays of gallium arsenide on germanium are evaluated and compared.

Space Mission Concept Development Using Concept Maturity Levels

Science.gov (United States)

Wessen, Randii R.; Borden, Chester; Ziemer, John; Kwok, Johnny

2013-01-01

Over the past five years, pre-project formulation experts at the Jet Propulsion Laboratory (JPL) has developed and implemented a method for measuring and communicating the maturity of space mission concepts. Mission concept development teams use this method, and associated tools, prior to concepts entering their Formulation Phases (Phase A/B). The organizing structure is Concept Maturity Level (CML), which is a classification system for characterizing the various levels of a concept's maturity. The key strength of CMLs is the ability to evolve mission concepts guided by an incremental set of assessment needs. The CML definitions have been expanded into a matrix form to identify the breadth and depth of analysis needed for a concept to reach a specific level of maturity. This matrix enables improved assessment and communication by addressing the fundamental dimensions (e.g., science objectives, mission design, technical risk, project organization, cost, export compliance, etc.) associated with mission concept evolution. JPL's collaborative engineering, dedicated concept development, and proposal teams all use these and other CML-appropriate design tools to advance their mission concept designs. This paper focuses on mission concept's early Pre-Phase A represented by CMLs 1- 4. The scope was limited due to the fact that CMLs 5 and 6 are already well defined based on the requirements documented in specific Announcement of Opportunities (AO) and Concept Study Report (CSR) guidelines, respectively, for competitive missions; and by NASA's Procedural Requirements NPR 7120.5E document for Projects in their Formulation Phase.

[The mission].

Science.gov (United States)

Ruiz Moreno, J; Blanch Mon, A

2000-01-01

After having made a historical review of the concept of mission statement, of evaluating its importance (See Part I), of describing the bases to create a mission statement from a strategic perspective and of analyzing the advantages of this concept, probably more important as a business policy (See Parts I and II), the authors proceed to analyze the mission statement in health organizations. Due to the fact that a mission statement is lacking in the majority of health organizations, the strategy of health organizations are not exactly favored; as a consequence, neither are its competitive advantage nor the development of its essential competencies. After presenting a series of mission statements corresponding to Anglo-Saxon health organizations, the authors highlight two mission statements corresponding to our social context. The article finishes by suggesting an adequate sequence for developing a mission statement in those health organizations having a strategic sense.

US Decadal Survey Outer Solar System Missions: Trajectory Options

Science.gov (United States)

Spilker, T. R.; Atkinson, D. H.; Strange, N. J.; Landau, D.

2012-04-01

The report of the US Planetary Science Decadal Survey (PSDS), released in draft form March 7, 2011, identifies several mission concepts involving travel to high-priority outer solar system (OSS) destinations. These include missions to Europa and Jupiter, Saturn and two of its satellites, and Uranus. Because travel to the OSS involves much larger distances and larger excursions out of the sun's gravitational potential well than inner solar system (ISS) missions, transfer trajectories for OSS missions are stronger drivers of mission schedule and resource requirements than for ISS missions. Various characteristics of each planet system, such as obliquity, radiation belts, rings, deep gravity wells, etc., carry ramifications for approach trajectories or trajectories within the systems. The maturity of trajectory studies for each of these destinations varies significantly. Europa has been the focus of studies for well over a decade. Transfer trajectory options from Earth to Jupiter are well understood. Current studies focus on trajectories within the Jovian system that could reduce the total mission cost of a Europa orbiter mission. Three missions to the Saturn system received high priority ratings in the PSDS report: two flagship orbital missions, one to Titan and one to Enceladus, and a Saturn atmospheric entry probe mission for NASA's New Frontiers Program. The Titan Saturn System Mission (TSSM) studies of 2007-2009 advanced our understanding of trajectory options for transfers to Saturn, including solar electric propulsion (SEP) trajectories. But SEP trajectories depend more on details of spacecraft and propulsion system characteristics than chemical trajectories, and the maturity of SEP trajectory search tools has not yet caught up with chemical trajectory tools, so there is still more useful research to be done on Saturn transfers. The TSSM studies revealed much about Saturn-orbiting trajectories that yield efficient and timely delivery to Titan or Enceladus

SCOSII: ESA's new generation of mission control systems: The user's perspective

Science.gov (United States)

Kaufeler, P.; Pecchioli, M.; Shurmer, I.

1994-01-01

In 1974 ESOC decided to develop a reusable Mission Control System infrastructure for ESA's missions operated under its responsibility. This triggered a long and successful product development line, which started with the Multi Mission Support System (MSSS) which entered in service in 1977 and is still being used today by the MARECS and ECS missions; it was followed in 1989 by a second generation of systems known as SCOS-I, which was/is used by the Hipparcos, ERS-1 and EURECA missions and will continue to support all future ESCO controlled missions until approximately 1995. In the meantime the increasing complexity of future missions together with the emergence of new hardware and software technologies have led ESOC to go for the development of a third generation of control systems, SCOSII, which will support their future missions up to at least the middle of the next decade. The objective of the paper is to present the characteristics of the SCOSII system from the perspective of the mission control team; i.e. it will concentrate on the improvements and advances in the performance, functionality and work efficiency of the system.

On the issues of probability distribution of GPS carrier phase observations

Science.gov (United States)

Luo, X.; Mayer, M.; Heck, B.

2009-04-01

In common practice the observables related to Global Positioning System (GPS) are assumed to follow a Gauss-Laplace normal distribution. Actually, full knowledge of the observables' distribution is not required for parameter estimation by means of the least-squares algorithm based on the functional relation between observations and unknown parameters as well as the associated variance-covariance matrix. However, the probability distribution of GPS observations plays a key role in procedures for quality control (e.g. outlier and cycle slips detection, ambiguity resolution) and in reliability-related assessments of the estimation results. Under non-ideal observation conditions with respect to the factors impacting GPS data quality, for example multipath effects and atmospheric delays, the validity of the normal distribution postulate of GPS observations is in doubt. This paper presents a detailed analysis of the distribution properties of GPS carrier phase observations using double difference residuals. For this purpose 1-Hz observation data from the permanent SAPOS

Joint probability of statistical success of multiple phase III trials.

Science.gov (United States)

Zhang, Jianliang; Zhang, Jenny J

2013-01-01

In drug development, after completion of phase II proof-of-concept trials, the sponsor needs to make a go/no-go decision to start expensive phase III trials. The probability of statistical success (PoSS) of the phase III trials based on data from earlier studies is an important factor in that decision-making process. Instead of statistical power, the predictive power of a phase III trial, which takes into account the uncertainty in the estimation of treatment effect from earlier studies, has been proposed to evaluate the PoSS of a single trial. However, regulatory authorities generally require statistical significance in two (or more) trials for marketing licensure. We show that the predictive statistics of two future trials are statistically correlated through use of the common observed data from earlier studies. Thus, the joint predictive power should not be evaluated as a simplistic product of the predictive powers of the individual trials. We develop the relevant formulae for the appropriate evaluation of the joint predictive power and provide numerical examples. Our methodology is further extended to the more complex phase III development scenario comprising more than two (K > 2) trials, that is, the evaluation of the PoSS of at least k₀ (k₀≤ K) trials from a program of K total trials. Copyright © 2013 John Wiley & Sons, Ltd.

K-Rankine systems for piloted and cargo Mars missions

International Nuclear Information System (INIS)

Mills, J.C.; Rovang, R.D.; Johnson, G.A.

1992-03-01

Studies are performed to demonstrate the attractiveness of potassium-Rankine (K-Rankine) nuclear electric propulsion (NEP) systems for both piloted and cargo Mars missions. The key results of the piloted mission study are that a full-up piloted mission can be accomplished with a trip time of less than 390 days with an attractive initial mass in low earth orbit (IMLEO) of 700 metric tons. This is achieved by coupling two advanced cermet fuel reactors (1550 K outlet temperature) to K-Rankine power-conversion systems to produce the 46 MWe needed to power advanced ion engines. This design approach offers an alternative to a more risky split-sprint mission where comparable trip times and IMLEO can be achieved with a nearer-term reactor (SP-100 at 1350 K outlet temperature) technology. The results of the cargo-mission study indicate that a lower-power K-Rankine system (5.5 MWe) operating at SP-100 reactor conditions would best perform a representative Mars cargo transport. A round-trip mission (480 days outbound; 600 day return) to Mars requires only 225 metric tons IMLEO and permit possible system reuse. 6 refs

Mission Planning System Increment 5 (MPS Inc 5)

Science.gov (United States)

2016-03-01

2016 Major Automated Information System Annual Report Mission Planning System Increment 5 (MPS Inc 5) Defense Acquisition Management Information...President’s Budget RDT&E - Research, Development, Test, and Evaluation SAE - Service Acquisition Executive TBD - To Be Determined TY - Then Year...Phone: 845-9625 DSN Fax: Date Assigned: May 19, 2014 Program Information Program Name Mission Planning System Increment 5 (MPS Inc 5) DoD

GRACE Status at Mission End

Science.gov (United States)

Tapley, B. D.; Flechtner, F. M.; Watkins, M. M.; Bettadpur, S. V.

2017-12-01

The twin satellites of the Gravity Recovery and Climate Experiment (GRACE) were launched on March 17, 2002 and have operated for nearly 16 years. The mission objectives are to observe the spatial and temporal variations of the Earth's mass through its effects on the gravity field at the GRACE satellite altitude. The mass changes observed are related to both the changes within the solid earth and the change within and between the Erath system components. A significant cause of the time varying mass is water motion and the GRACE mission has provided a continuous decade long measurement sequence which characterizes the seasonal cycle of mass transport between the oceans, land, cryosphere and atmosphere; its inter-annual variability; and the climate driven secular, or long period, mass transport signals. The fifth reanalysis on the mission data set, the RL05 data, were released in mid-2013. With the planned launch of GRACE Follow-On in early 2018, plans are underway for a reanalysis that will be consistent with the GRACE FO processing standards. The mission is entering the final phases of its operation life with mission end expected to occur in early 2018. The current mission operations strategy emphasizes extending the mission lifetime to obtain an overlap with the GRACE FO. This presentation will review the mission status and the projections for mission lifetime, describe the current operations philosophy and its impact on the science data, discuss the issues related to achieving the GRACE and GRACE FO connection and discuss issues related to science data products during this phase of the mission period.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Bolivia. Draft

International Nuclear Information System (INIS)

Leroy, Jacques; Mueller-Kahle, Eberhard

1982-08-01

The uranium exploration done so far in Bolivia has been carried out by COBOEN, partly with IAEA support, and AGIP S.p.A. of Italy, which between 1974 and 1978 explored four areas in various parts of Bolivia under a production sharing contract with COBOEN. The basic objective of the International Uranium Resources Evaluation Project (IUREP) is to 'review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for discovery of additional uranium resources, and to suggest new exploitation efforts which might be carried out in promising areas in collaboration with the country concerned'. Following the initial bibliographic study which formed Phase I of IUREP, it was envisaged that a further assessment in cooperation with, and within, the country concerned would provide a better delineation of areas of high potential and a more reliable estimate as to the degree of favourability for the discovery of additional uranium resources. It was planned that such work would be accomplished through field missions to the country concerned and that these field missions and the resulting report would be known as the Orientation Phase of IUREP. The purpose of the Orientation Phase mission to Bolivia was a) to develop a better understanding of the uranium potential of the country, b) to make an estimate of the Speculative Resources of the country, c) to delineate areas favourable for the discovery of these uranium resources, d) to make recommendations as appropriate on the best methods for evaluating the favourable areas, operating procedures and estimated possible costs, e) to develop the logistical data required to carry out any possible further work, and f) to compile a report which would be immediately available to the Bolivian authorities. The mission reports contains information about a general introduction, non-uranium exploration and mining in Bolivia, manpower in exploration, geological review of Bolivia, past uranium

ESA strategy for human exploration and the Lunar Lander Mission

Science.gov (United States)

Gardini, B.

As part of ESAs Aurora Exploration programme, the Agency has defined, since 2001, a road map for exploration in which, alongside robotic exploration missions, the International Space Station (ISS) and the Moon play an essential role on the way to other destinations in the Solar System, ultimately to a human mission to Mars in a more distant future. In the frame of the Human Spaceflight programme the first European Lunar Lander Mission, with a launch date on 2018, has been defined, targeting the lunar South Pole region to capitalize on unique illumination conditions and provide the opportunity to carry out scientific investigations in a region of the Moon not explored so far. The Phase B1 industrial study, recently initiated, will consolidate the mission design and prepare the ground for the approval of the full mission development phase at the 2012 ESA Council at Ministerial. This paper describes the mission options which have been investigated in the past Phase A studies and presents the main activities foreseen in the Phase B1 to consolidate the mission design, including a robust bread-boards and technology development programme. In addition, the approach to overcoming the mission's major technical and environmental challenges and the activities to advance the definition of the payload elements will be described.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Bolivia

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Bolivia. The IUREP Orientation Phase mission to Bolivia estimates that the Speculative Uranium Resources of that country fall within the range of 100 to 107 500 tonnes uranium. The majority of this potential is expected to be located in the Precambrian crystalline and sedimentary rocks of the southwestern part of the Central Brazilian Shield. Other potentially favourable geologic environments include Palaeozoic two mica granites and their metasedimentary hosts, Mesozoic granites and granodiorites as well as the intruded formations and finally Tertiary acid to intermediate volcanics. The mission recommends that approximately US$ 13 million be spent on exploration in Bolivia over a five-year period. The majority of this expenditure would be for airborne and surface exploration utilising geologic, magnetometric, radiometric, and geochemical methods and some pitting, trenching, tunneling and drilling to further evaluate the discovered occurrences. (author)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Peru

International Nuclear Information System (INIS)

1984-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (TUREP) Mission to Peru. The IUREP Orientation Phase Mission to Peru estimates that the Speculative Resources of that country fall within the range of 6 000 to 11 000 tonnes uranium. The majority of this potential is expected to be located in Late Tertiary ignimbrites and associated sediments in the high Andes of southern Peru. Other favourable geological environments include calcretes, developed from Tertiary volcanogenic sources over the Precambrian in the Pacific Coastal desert in southern Peru, and Hercynian subvolcanic granites in the eastern Cordillera of southern Peru. The Mission recommends that over a period of five years approximately U.S. $10 million be spent on exploration in Peru. The majority of this would be spent on drilling ($5 million) and tunnelling ($2 million) with an additional $3 million on surface and airborne radiometric surveys. (author)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Ghana

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Ghana. The IUREP Orientation Phase Mission to Ghana estimates that the Speculative Resources of that country fall within the range of 15 000 to 40 000 tonnes of uranium. The majority of this potential is expected to be located in the Proterozoic Panafrican Mobile Belt (up to 17 000 tonnes uranium) and the Paleozoic Obosum Beds of the Voltaian basin (up to 15 000 tonnes uranium), the remainder being associated with various other geological environments. The mission recommends that over a period of three (3) years approximately U.S. $5 million) would be spent on exploration in Ghana. A major part of this (U.S $2 million) would be spent on an airborne spectrometer survey over the Voltaian basin (Obosum beds), much of the remainder being spent on ground surveys, trenching and percussion drilling. (author)

A Sustainable, Reliable Mission-Systems Architecture that Supports a System of Systems Approach to Space Exploration

Science.gov (United States)

Watson, Steve; Orr, Jim; O'Neil, Graham

2004-01-01

A mission-systems architecture based on a highly modular "systems of systems" infrastructure utilizing open-standards hardware and software interfaces as the enabling technology is absolutely essential for an affordable and sustainable space exploration program. This architecture requires (a) robust communication between heterogeneous systems, (b) high reliability, (c) minimal mission-to-mission reconfiguration, (d) affordable development, system integration, and verification of systems, and (e) minimum sustaining engineering. This paper proposes such an architecture. Lessons learned from the space shuttle program are applied to help define and refine the model.

Spatial correlations and probability density function of the phase difference in a developed speckle-field: numerical and natural experiments

International Nuclear Information System (INIS)

Mysina, N Yu; Maksimova, L A; Ryabukho, V P; Gorbatenko, B B

2015-01-01

Investigated are statistical properties of the phase difference of oscillations in speckle-fields at two points in the far-field diffraction region, with different shapes of the scatterer aperture. Statistical and spatial nonuniformity of the probability density function of the field phase difference is established. Numerical experiments show that, for the speckle-fields with an oscillating alternating-sign transverse correlation function, a significant nonuniformity of the probability density function of the phase difference in the correlation region of the field complex amplitude, with the most probable values 0 and p, is observed. A natural statistical interference experiment using Young diagrams has confirmed the results of numerical experiments. (laser applications and other topics in quantum electronics)

Kilowatt-Class Fission Power Systems for Science and Human Precursor Missions

Science.gov (United States)

Mason, Lee S.; Gibson, Marc Andrew; Poston, Dave

2013-01-01

Nuclear power provides an enabling capability for NASA missions that might otherwise be constrained by power availability, mission duration, or operational robustness. NASA and the Department of Energy (DOE) are developing fission power technology to serve a wide range of future space uses. Advantages include lower mass, longer life, and greater mission flexibility than competing power system options. Kilowatt-class fission systems, designated "Kilopower," were conceived to address the need for systems to fill the gap above the current 100-W-class radioisotope power systems being developed for science missions and below the typical 100-k We-class reactor power systems being developed for human exploration missions. This paper reviews the current fission technology project and examines some Kilopower concepts that could be used to support future science missions or human precursors.

Adding a Mission to the Joint Polar Satellite System (JPSS) Common Ground System (CGS)

Science.gov (United States)

Miller, S. W.; Grant, K. D.; Jamilkowski, M. L.

2014-12-01

The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a multi-mission enterprise system serving NOAA, NASA and their national and international partners. The CGS provides a wide range of support to a number of missions: 1) Command and control and mission management for the Suomi National Polar-orbiting Partnership (S-NPP) mission today, expanding this support to the JPSS-1 satellite and the Polar Free Flyer mission in 2017 2) Data acquisition via a Polar Receptor Network (PRN) for S-NPP, the Japan Aerospace Exploration Agency's (JAXA) Global Change Observation Mission - Water (GCOM-W1), POES, and the Defense Meteorological Satellite Program (DMSP) and Coriolis/WindSat for the Department of Defense (DoD) 3) Data routing over a global fiber Wide Area Network (WAN) for S-NPP, JPSS-1, Polar Free Flyer, GCOM-W1, POES, DMSP, Coriolis/WindSat, the NASA Space Communications and Navigation (SCaN, which includes several Earth Observing System [EOS] missions), MetOp for the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), and the National Science Foundation (NSF) 4) Environmental data processing and distribution for S-NPP, GCOM-W1 and JPSS-1 With this established infrastructure and existing suite of missions, the CGS

Mission Operations Planning and Scheduling System (MOPSS)

Science.gov (United States)

Wood, Terri; Hempel, Paul

2011-01-01

MOPSS is a generic framework that can be configured on the fly to support a wide range of planning and scheduling applications. It is currently used to support seven missions at Goddard Space Flight Center (GSFC) in roles that include science planning, mission planning, and real-time control. Prior to MOPSS, each spacecraft project built its own planning and scheduling capability to plan satellite activities and communications and to create the commands to be uplinked to the spacecraft. This approach required creating a data repository for storing planning and scheduling information, building user interfaces to display data, generating needed scheduling algorithms, and implementing customized external interfaces. Complex scheduling problems that involved reacting to multiple variable situations were analyzed manually. Operators then used the results to add commands to the schedule. Each architecture was unique to specific satellite requirements. MOPSS is an expert system that automates mission operations and frees the flight operations team to concentrate on critical activities. It is easily reconfigured by the flight operations team as the mission evolves. The heart of the system is a custom object-oriented data layer mapped onto an Oracle relational database. The combination of these two technologies allows a user or system engineer to capture any type of scheduling or planning data in the system's generic data storage via a GUI.

Hierarchthis: An Interactive Interface for Identifying Mission-Relevant Components of the Advanced Multi-Mission Operations System

Science.gov (United States)

Litomisky, Krystof

2012-01-01

Even though NASA's space missions are many and varied, there are some tasks that are common to all of them. For example, all spacecraft need to communicate with other entities, and all spacecraft need to know where they are. These tasks use tools and services that can be inherited and reused between missions, reducing systems engineering effort and therefore reducing cost.The Advanced Multi-Mission Operations System, or AMMOS, is a collection of multimission tools and services, whose development and maintenance are funded by NASA. I created HierarchThis, a plugin designed to provide an interactive interface to help customers identify mission-relevant tools and services. HierarchThis automatically creates diagrams of the AMMOS database, and then allows users to show/hide specific details through a graphical interface. Once customers identify tools and services they want for a specific mission, HierarchThis can automatically generate a contract between the Multimission Ground Systems and Services Office, which manages AMMOS, and the customer. The document contains the selected AMMOS components, along with their capabilities and satisfied requirements. HierarchThis reduces the time needed for the process from service selections to having a mission-specific contract from the order of days to the order of minutes.

The Pacific Exploratory Mission-West Phase B: February-March, 1994

Science.gov (United States)

Hoell, J. M.; Davis, D. D.; Liu, S. C.; Newell, R. E.; Akimoto, H.; McNeal, R. J.; Bendura, R. J.

1997-12-01

The NASA Pacific Exploratory Mission in the Western Pacific Ocean (PEM-West) is a major component of the East Asia/North Pacific Regional Study (APARE), a project within the International Global Atmospheric Chemistry (IGAC) Program. The broad objectives of the PEM-West/APARE initiative are to study chemical processes and long-range transport of atmospheric trace species over the north-west Pacific Ocean and to estimate the magnitude of the human impact on these species over this region. The first phase of PEM-West (PEM-West A) was conducted in September-October 1991, a period characterized by minimum outflow from the Asian continent. The second phase of this mission, PEM-West B, was conducted during February-March 1994, a period characterized by enhanced outflow from the Asian continent. Both field campaigns of PEM-West included intensive airborne measurements of trace gases and aerosols from the NASA DC-8 aircraft coordinated with measurements at surface sites. This paper reports the experimental design for PEM-West B and provides a brief summary of the salient results of the PEM-West B campaign with particular emphases on the difference/similarities between phases A and B. Results from the two campaigns clearly quantify, from a trace gas perspective, the seasonal differences in the continental outflow that were qualitatively anticipated based upon meteorological considerations, and show the impact of major meteorological features within the region on the quality of tropospheric air over the North Pacific Ocean regions. The PEM-West database provides a "baseline" tool by which future assessments of a continuing impact of Asian emissions on remote Pacific regions can be judged. [These data are currently available through the Global Troposhperic Experiment Data Archive at NASA's Langley Research Center (http://www-gte.larc.nasa.gov) and the Langley Distributed Archive Center (http://eosdis.larc.nasa.gov)].

Probabilities of False Alarm for Vital Sign Detection on the Basis of a Doppler Radar System

Directory of Open Access Journals (Sweden)

Nguyen Thi Phuoc Van

2018-02-01

Full Text Available Vital detection on the basis of Doppler radars has drawn a great deal of attention from researchers because of its high potential for applications in biomedicine, surveillance, and finding people alive under debris during natural hazards. In this research, the signal-to-noise ratio (SNR of the remote vital-sign detection system is investigated. On the basis of different types of noise, such as phase noise, Gaussian noise, leakage noise between the transmitting and receiving antennae, and so on, the SNR of the system has first been examined. Then the research has focused on the investigation of the detection and false alarm probabilities of the system when the transmission link between the human and the radar sensor system took the Nakagami-m channel model. The analytical model for the false alarm and the detection probabilities of the system have been derived. The proposed theoretical models for the SNR and detection probability match with the simulation and measurement results. These theoretical models have the potential to be used as good references for the hardware development of the vital-sign detection radar sensor system.

Optimization of Second Fault Detection Thresholds to Maximize Mission POS

Science.gov (United States)

Anzalone, Evan

2018-01-01

In order to support manned spaceflight safety requirements, the Space Launch System (SLS) has defined program-level requirements for key systems to ensure successful operation under single fault conditions. To accommodate this with regards to Navigation, the SLS utilizes an internally redundant Inertial Navigation System (INS) with built-in capability to detect, isolate, and recover from first failure conditions and still maintain adherence to performance requirements. The unit utilizes multiple hardware- and software-level techniques to enable detection, isolation, and recovery from these events in terms of its built-in Fault Detection, Isolation, and Recovery (FDIR) algorithms. Successful operation is defined in terms of sufficient navigation accuracy at insertion while operating under worst case single sensor outages (gyroscope and accelerometer faults at launch). In addition to first fault detection and recovery, the SLS program has also levied requirements relating to the capability of the INS to detect a second fault, tracking any unacceptable uncertainty in knowledge of the vehicle's state. This detection functionality is required in order to feed abort analysis and ensure crew safety. Increases in navigation state error and sensor faults can drive the vehicle outside of its operational as-designed environments and outside of its performance envelope causing loss of mission, or worse, loss of crew. The criteria for operation under second faults allows for a larger set of achievable missions in terms of potential fault conditions, due to the INS operating at the edge of its capability. As this performance is defined and controlled at the vehicle level, it allows for the use of system level margins to increase probability of mission success on the operational edges of the design space. Due to the implications of the vehicle response to abort conditions (such as a potentially failed INS), it is important to consider a wide range of failure scenarios in terms of

Management assessment of tank waste remediation system contractor readiness to proceed with phase 1B privatization

International Nuclear Information System (INIS)

Certa, P.J.

1998-01-01

Readiness to Proceed With Phase 1B Privatization documents the processes used to determine readiness to proceed with tank waste treatment technologies from private industry, now known as TWRS privatization. An overall systems approach was applied to develop action plans to support the retrieval and disposal mission of the TWRS Project. The systems and infrastructure required to support the mission are known. Required systems are either in place or plans have been developed to ensure they exist when needed. Since October 1996 a robust system engineering approach to establishing integrated Technical Baselines, work breakdown structures, tank farms organizational structure and configurations, work scope, and costs has become part of the culture within the TWRS Project. An analysis of the programmatic, management, and technical activities necessary to declare readiness to proceed with execution of the mission demonstrates that the system, personnel, and hardware will be on line and ready to support the private contractors. The systems approach included defining the retrieval and disposal mission requirements and evaluating the readiness of the Project Hanford Management Contract (PHMC) team to support initiation of waste processing by the private contractors in June 2002 and to receive immobilized waste shortly thereafter. The Phase 1 feed delivery requirements from the private contractor Requests for Proposal were reviewed. Transfer piping routes were mapped, existing systems were evaluated, and upgrade requirements were defined

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Madagascar

International Nuclear Information System (INIS)

1985-01-01

A report has recently been made public which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Madagascar. The IUREP Orientation Phase Mission to Madagascar estimates the Speculative Resources of that country to be within the wide range of 4 000 to 38 000 tonnes uranium. Such resources could lie in areas with known occurrences (uranothorianite, Ft. Dauphin up to 5 000 t U, i.e. 'pegmatoids'; uranocircite, Antsirabe up to 3 000 t U in Neogene sediments; carnotiteautonite, Karoo area up to 30 000 t U in sandstones and in areas with as yet untested environments (e.g. related to unconformities and calcretes). Modifications to existing uranium exploration programmes are suggested and policy alternatives reviewed. No specific budget is proposed. (author)

SMART: A Propositional Logic-Based Trade Analysis and Risk Assessment Tool for a Complex Mission

Science.gov (United States)

Ono, Masahiro; Nicholas, Austin; Alibay, Farah; Parrish, Joseph

2015-01-01

This paper introduces a new trade analysis software called the Space Mission Architecture and Risk Analysis Tool (SMART). This tool supports a high-level system trade study on a complex mission, such as a potential Mars Sample Return (MSR) mission, in an intuitive and quantitative manner. In a complex mission, a common approach to increase the probability of success is to have redundancy and prepare backups. Quantitatively evaluating the utility of adding redundancy to a system is important but not straightforward, particularly when the failure of parallel subsystems are correlated.

Playing Around in the Solar System: Mini-games for Many Missions

Science.gov (United States)

Fisher, D. K.; Leon, N.; Fitzpatrick, A. J.; Wessen, A.

2010-12-01

Several NASA solar system missions will have major milestones during 2011, the Year of the Solar System. These events include launches, encounters, and orbit insertions. Other missions will continue the explorations already underway. The “Year of the Solar System Game” on The Space Place website (http://spaceplace.nasa.gov/en/kids/solar-system) brings all these efforts together in the context of the whole solar system. The game helps to build awareness of the characteristics of our solar system and some of the missions that are continuing to advance our knowledge and understanding. It is one of many educational tools being developed and deployed for the Year of the Solar System. The game is a “super-game” that encompasses a number of mission-related “mini-games.” The mini-games can be played individually, and they all contribute toward achievements in the super-game. The enveloping interface for all the games is an animated solar system. The player clicks on a planet or a moon, sees a close-up image, and reads a short paragraph about the object. If the object has been endowed with a mission mini-game, player can click on the tiny spacecraft, read about the mission, then play the game—or, if impatient, just immediately play the game (and read about the mission later, we hope). A score “page” keeps track of the player’s achievements and scores. Players earn achievements by reading about the planets, moons, asteroids, comets, and missions and by playing the mission mini-games. The game targets upper elementary age children, as does the entire Space Place website. Each mini-game, although simple, incorporates elements of the spacecrafts’ missions and their target objects. For example, in Cassini Commander, the player must navigate the Cassini spacecraft through gaps in Saturn’s rings and around Saturn’s moons. The super-game is designed to accommodate any number of mission mini-games, so we are hoping to continue to add missions and increase

A Scenario-Based Process for Requirements Development: Application to Mission Operations Systems

Science.gov (United States)

Bindschadler, Duane L.; Boyles, Carole A.

2008-01-01

The notion of using operational scenarios as part of requirements development during mission formulation (Phases A & B) is widely accepted as good system engineering practice. In the context of developing a Mission Operations System (MOS), there are numerous practical challenges to translating that notion into the cost-effective development of a useful set of requirements. These challenges can include such issues as a lack of Project-level focus on operations issues, insufficient or improper flowdown of requirements, flowdown of immature or poor-quality requirements from Project level, and MOS resource constraints (personnel expertise and/or dollars). System engineering theory must be translated into a practice that provides enough structure and standards to serve as guidance, but that retains sufficient flexibility to be tailored to the needs and constraints of a particular MOS or Project. We describe a detailed, scenario-based process for requirements development. Identifying a set of attributes for high quality requirements, we show how the portions of the process address many of those attributes. We also find that the basic process steps are robust, and can be effective even in challenging Project environments.

Probability density function evolution of power systems subject to stochastic variation of renewable energy

Science.gov (United States)

Wei, J. Q.; Cong, Y. C.; Xiao, M. Q.

2018-05-01

As renewable energies are increasingly integrated into power systems, there is increasing interest in stochastic analysis of power systems.Better techniques should be developed to account for the uncertainty caused by penetration of renewables and consequently analyse its impacts on stochastic stability of power systems. In this paper, the Stochastic Differential Equations (SDEs) are used to represent the evolutionary behaviour of the power systems. The stationary Probability Density Function (PDF) solution to SDEs modelling power systems excited by Gaussian white noise is analysed. Subjected to such random excitation, the Joint Probability Density Function (JPDF) solution to the phase angle and angular velocity is governed by the generalized Fokker-Planck-Kolmogorov (FPK) equation. To solve this equation, the numerical method is adopted. Special measure is taken such that the generalized FPK equation is satisfied in the average sense of integration with the assumed PDF. Both weak and strong intensities of the stochastic excitations are considered in a single machine infinite bus power system. The numerical analysis has the same result as the one given by the Monte Carlo simulation. Potential studies on stochastic behaviour of multi-machine power systems with random excitations are discussed at the end.

Predictive Modeling for NASA Entry, Descent and Landing Missions

Science.gov (United States)

Wright, Michael

2016-01-01

Entry, Descent and Landing (EDL) Modeling and Simulation (MS) is an enabling capability for complex NASA entry missions such as MSL and Orion. MS is used in every mission phase to define mission concepts, select appropriate architectures, design EDL systems, quantify margin and risk, ensure correct system operation, and analyze data returned from the entry. In an environment where it is impossible to fully test EDL concepts on the ground prior to use, accurate MS capability is required to extrapolate ground test results to expected flight performance.

Expert systems and advanced automation for space missions operations

Science.gov (United States)

Durrani, Sajjad H.; Perkins, Dorothy C.; Carlton, P. Douglas

1990-01-01

Increased complexity of space missions during the 1980s led to the introduction of expert systems and advanced automation techniques in mission operations. This paper describes several technologies in operational use or under development at the National Aeronautics and Space Administration's Goddard Space Flight Center. Several expert systems are described that diagnose faults, analyze spacecraft operations and onboard subsystem performance (in conjunction with neural networks), and perform data quality and data accounting functions. The design of customized user interfaces is discussed, with examples of their application to space missions. Displays, which allow mission operators to see the spacecraft position, orientation, and configuration under a variety of operating conditions, are described. Automated systems for scheduling are discussed, and a testbed that allows tests and demonstrations of the associated architectures, interface protocols, and operations concepts is described. Lessons learned are summarized.

Time of Arrival Estimation in Probability-Controlled Generalized CDMA Systems

Directory of Open Access Journals (Sweden)

Hagit Messer

2007-11-01

Full Text Available In recent years, more and more wireless communications systems are required to provide also a positioning measurement. In code division multiple access (CDMA communication systems, the positioning accuracy is significantly degraded by the multiple access interference (MAI caused by other users in the system. This MAI is commonly managed by a power control mechanism, and yet, MAI has a major effect on positioning accuracy. Probability control is a recently introduced interference management mechanism. In this mechanism, a user with excess power chooses not to transmit some of its symbols. The information in the nontransmitted symbols is recovered by an error-correcting code (ECC, while all other users receive a more reliable data during these quiet periods. Previous research had shown that the implementation of a probability control mechanism can significantly reduce the MAI. In this paper, we show that probability control also improves the positioning accuracy. We focus on time-of-arrival (TOA based positioning systems. We analyze the TOA estimation performance in a generalized CDMA system, in which the probability control mechanism is employed, where the transmitted signal is noncontinuous with a symbol transmission probability smaller than 1. The accuracy of the TOA estimation is determined using appropriate modifications of the Cramer-Rao bound on the delay estimation. Keeping the average transmission power constant, we show that the TOA accuracy of each user does not depend on its transmission probability, while being a nondecreasing function of the transmission probability of any other user. Therefore, a generalized, noncontinuous CDMA system with a probability control mechanism can always achieve better positioning performance, for all users in the network, than a conventional, continuous, CDMA system.

The extinction probability in systems randomly varying in time

Directory of Open Access Journals (Sweden)

Imre Pázsit

2017-09-01

Full Text Available The extinction probability of a branching process (a neutron chain in a multiplying medium is calculated for a system randomly varying in time. The evolution of the first two moments of such a process was calculated previously by the authors in a system randomly shifting between two states of different multiplication properties. The same model is used here for the investigation of the extinction probability. It is seen that the determination of the extinction probability is significantly more complicated than that of the moments, and it can only be achieved by pure numerical methods. The numerical results indicate that for systems fluctuating between two subcritical or two supercritical states, the extinction probability behaves as expected, but for systems fluctuating between a supercritical and a subcritical state, there is a crucial and unexpected deviation from the predicted behaviour. The results bear some significance not only for neutron chains in a multiplying medium, but also for the evolution of biological populations in a time-varying environment.

Cassini’s Discoveries at Saturn and the Proposed Cassini Solstice Mission

Science.gov (United States)

Pappalardo, R. T.; Spilker, L. J.; Mitchell, R. T.; Cuzzi, J.; Gombosi, T. I.; Ingersoll, A. P.; Lunine, J. I.

2009-12-01

Understanding of the Saturn system has been greatly enhanced by the Cassini-Huygens mission. Fundamental discoveries have altered our views of Saturn, Titan and the other icy satellites, the rings, and magnetosphere of the system. Key discoveries include: water-rich plumes emanating from the south pole of Enceladus; hints of possible activity on Dione and of rings around Rhea; a methane hydrological cycle on Titan complete with fluvial erosion, lakes, and seas of liquid methane and ethane; non-axisymmetric ring microstructure in all moderate optical depth rings; south polar vortices on Saturn; and a unique magnetosphere that shares characteristics with both Earth’s and Jupiter’s magnetospheres. These new discoveries are directly relevant to current Solar System science goals including: planet and satellite formation processes, formation of gas giants, the nature of organic material, the history of volatiles, habitable zones and processes for life, processes that shape planetary bodies, and evolution of exoplanets. The proposed 7-year Cassini Solstice Mission would address new questions that have arisen during the Cassini Prime and Equinox Missions, and would observe seasonal and temporal change in the Saturn system to prepare for future missions to Saturn, Titan, and Enceladus. The proposed Cassini Solstice Mission would provide new science in three ways. First, it would observe seasonally and temporally dependent processes on Saturn, Titan and other icy satellites, and within the rings and magnetosphere, in a hitherto unobserved seasonal phase from equinox to solstice. Second, it would address new questions that have arisen during the mission thus far, providing qualitatively new measurements (e.g. of Enceladus and Titan) which could not be accommodated in the earlier mission phases. Tthird, it would conduct a close-in mission phase at Saturn that would provide unique science including comparison to the Juno observations at Jupiter.

MILITARY MISSION COMBAT EFFICIENCY ESTIMATION SYSTEM

Directory of Open Access Journals (Sweden)

Ighoyota B. AJENAGHUGHRURE

2017-04-01

Full Text Available Military infantry recruits, although trained, lacks experience in real-time combat operations, despite the combat simulations training. Therefore, the choice of including them in military operations is a thorough and careful process. This has left top military commanders with the tough task of deciding, the best blend of inexperienced and experienced infantry soldiers, for any military operation, based on available information on enemy strength and capability. This research project delves into the design of a mission combat efficiency estimator (MCEE. It is a decision support system that aids top military commanders in estimating the best combination of soldiers suitable for different military operations, based on available information on enemy’s combat experience. Hence, its advantages consist of reducing casualties and other risks that compromises the entire operation overall success, and also boosting the morals of soldiers in an operation, with such information as an estimation of combat efficiency of their enemies. The system was developed using Microsoft Asp.Net and Sql server backend. A case study test conducted with the MECEE system, reveals clearly that the MECEE system is an efficient tool for military mission planning in terms of team selection. Hence, when the MECEE system is fully deployed it will aid military commanders in the task of decision making on team members’ combination for any given operation based on enemy personnel information that is well known beforehand. Further work on the MECEE will be undertaken to explore fire power types and impact in mission combat efficiency estimation.

Management assessment of tank waste remediation system contractor readiness to proceed with phase 1B privatization

International Nuclear Information System (INIS)

Honeyman, J.O.

1998-01-01

This Management Assessment of Tank Waste Remediation System (TWRS) Contractor Readiness to Proceed With Phase 1B Privatization documents the processes used to determine readiness to proceed with tank waste treatment technologies from private industry, now known as TWRS privatization. An overall systems approach was applied to develop action plans to support the retrieval and disposal mission of the TWRS Project. The systems and infrastructure required to support the mission are known. Required systems are either in place or plans have been developed to ensure they exist when needed. Since October 1996 a robust system engineering approach to establishing integrated Technical Baselines, work breakdown structures, tank farms organizational structure and configurations, work scope, and costs has become part of the culture within the TWRS Project. An analysis of the programmatic, management, and technical activities necessary to declare readiness to proceed with execution of the mission demonstrates that the system, personnel, and hardware will be on-line and ready to support the private contractors. The systems approach included defining the retrieval and disposal mission requirements and evaluating the readiness of the Project Hanford Management Contract (PHMC) team to support initiation of waste processing by the private contractors in June 2002 and to receive immobilized waste shortly thereafter. The Phase 1 feed delivery requirements from the private contractor Requests for Proposal were reviewed. Transfer piping routes were mapped, existing systems were evaluated, and upgrade requirements were defined

MICROSCOPE Mission: on-orbit assessment of the Drag-Free and Attitude Control System

DEFF Research Database (Denmark)

Prieur, Pascal; Lienart, Thomas; Rodrigues, Manuel

Microscope successfully completed in November 2016 its on-orbit assessment. The paper begins with a brief description of the mission, the challenging performances the DFACS has to comply with and how they led to the hardwareand software design. Then we go through the major phases of the commissio......Microscope successfully completed in November 2016 its on-orbit assessment. The paper begins with a brief description of the mission, the challenging performances the DFACS has to comply with and how they led to the hardwareand software design. Then we go through the major phases...

Mission hazard assessment for STARS Mission 1 (M1) in the Marshall Islands area

Energy Technology Data Exchange (ETDEWEB)

Outka, D.E.; LaFarge, R.A.

1993-07-01

A mission hazard assessment has been performed for the Strategic Target System Mission 1 (known as STARS M1) for hazards due to potential debris impact in the Marshall Islands area. The work was performed at Sandia National Laboratories as a result of discussion with Kwajalein Missile Range (KMR) safety officers. The STARS M1 rocket will be launched from the Kauai Test Facility (KTF), Hawaii, and deliver two payloads to within the viewing range of sensors located on the Kwajalein Atoll. The purpose of this work has been to estimate upper bounds for expected casualty rates and impact probability or the Marshall Islands areas which adjoin the STARS M1 instantaneous impact point (IIP) trace. This report documents the methodology and results of the analysis.

System engineering of complex optical systems for mission assurance and affordability

Science.gov (United States)

Ahmad, Anees

2017-08-01

Affordability and reliability are equally important as the performance and development time for many optical systems for military, space and commercial applications. These characteristics are even more important for the systems meant for space and military applications where total lifecycle costs must be affordable. Most customers are looking for high performance optical systems that are not only affordable but are designed with "no doubt" mission assurance, reliability and maintainability in mind. Both US military and commercial customers are now demanding an optimum balance between performance, reliability and affordability. Therefore, it is important to employ a disciplined systems design approach for meeting the performance, cost and schedule targets while keeping affordability and reliability in mind. The US Missile Defense Agency (MDA) now requires all of their systems to be engineered, tested and produced according to the Mission Assurance Provisions (MAP). These provisions or requirements are meant to ensure complex and expensive military systems are designed, integrated, tested and produced with the reliability and total lifecycle costs in mind. This paper describes a system design approach based on the MAP document for developing sophisticated optical systems that are not only cost-effective but also deliver superior and reliable performance during their intended missions.

Benefits of advanced software techniques for mission planning systems

Science.gov (United States)

Gasquet, A.; Parrod, Y.; Desaintvincent, A.

1994-10-01

The increasing complexity of modern spacecraft, and the stringent requirement for maximizing their mission return, call for a new generation of Mission Planning Systems (MPS). In this paper, we discuss the requirements for the Space Mission Planning and the benefits which can be expected from Artificial Intelligence techniques through examples of applications developed by Matra Marconi Space.

Relationship between the Wigner function and the probability density function in quantum phase space representation

International Nuclear Information System (INIS)

Li Qianshu; Lue Liqiang; Wei Gongmin

2004-01-01

This paper discusses the relationship between the Wigner function, along with other related quasiprobability distribution functions, and the probability density distribution function constructed from the wave function of the Schroedinger equation in quantum phase space, as formulated by Torres-Vega and Frederick (TF). At the same time, a general approach in solving the wave function of the Schroedinger equation of TF quantum phase space theory is proposed. The relationship of the wave functions between the TF quantum phase space representation and the coordinate or momentum representation is thus revealed

Advances in Autonomous Systems for Missions of Space Exploration

Science.gov (United States)

Gross, A. R.; Smith, B. D.; Briggs, G. A.; Hieronymus, J.; Clancy, D. J.

New missions of space exploration will require unprecedented levels of autonomy to successfully accomplish their objectives. Both inherent complexity and communication distances will preclude levels of human involvement common to current and previous space flight missions. With exponentially increasing capabilities of computer hardware and software, including networks and communication systems, a new balance of work is being developed between humans and machines. This new balance holds the promise of meeting the greatly increased space exploration requirements, along with dramatically reduced design, development, test, and operating costs. New information technologies, which take advantage of knowledge-based software, model-based reasoning, and high performance computer systems, will enable the development of a new generation of design and development tools, schedulers, and vehicle and system health monitoring and maintenance capabilities. Such tools will provide a degree of machine intelligence and associated autonomy that has previously been unavailable. These capabilities are critical to the future of space exploration, since the science and operational requirements specified by such missions, as well as the budgetary constraints that limit the ability to monitor and control these missions by a standing army of ground- based controllers. System autonomy capabilities have made great strides in recent years, for both ground and space flight applications. Autonomous systems have flown on advanced spacecraft, providing new levels of spacecraft capability and mission safety. Such systems operate by utilizing model-based reasoning that provides the capability to work from high-level mission goals, while deriving the detailed system commands internally, rather than having to have such commands transmitted from Earth. This enables missions of such complexity and communications distance as are not otherwise possible, as well as many more efficient and low cost

GPS Navigation for the Magnetospheric Multi-Scale Mission

Science.gov (United States)

Bamford, William; Mitchell, Jason; Southward, Michael; Baldwin, Philip; Winternitz, Luke; Heckler, Gregory; Kurichh, Rishi; Sirotzky, Steve

2009-01-01

In 2014. NASA is scheduled to launch the Magnetospheric Multiscale Mission (MMS), a four-satellite formation designed to monitor fluctuations in the Earth's magnetosphere. This mission has two planned phases with different orbits (1? x 12Re and 1.2 x 25Re) to allow for varying science regions of interest. To minimize ground resources and to mitigate the probability of collisions between formation members, an on-board orbit determination system consisting of a Global Positioning System (GPS) receiver and crosslink transceiver was desired. Candidate sensors would be required to acquire GPS signals both below and above the constellation while spinning at three revolutions-per-minute (RPM) and exchanging state and science information among the constellation. The Intersatellite Ranging and Alarm System (IRAS), developed by Goddard Space Flight Center (GSFC) was selected to meet this challenge. IRAS leverages the eight years of development GSFC has invested in the Navigator GPS receiver and its spacecraft communication expertise, culminating in a sensor capable of absolute and relative navigation as well as intersatellite communication. The Navigator is a state-of-the-art receiver designed to acquire and track weak GPS signals down to -147dBm. This innovation allows the receiver to track both the main lobe and the much weaker side lobe signals. The Navigator's four antenna inputs and 24 tracking channels, together with customized hardware and software, allow it to seamlessly maintain visibility while rotating. Additionally, an extended Kalman filter provides autonomous, near real-time, absolute state and time estimates. The Navigator made its maiden voyage on the Space Shuttle during the Hubble Servicing Mission, and is scheduled to fly on MMS as well as the Global Precipitation Measurement Mission (GPM). Additionally, Navigator's acquisition engine will be featured in the receiver being developed for the Orion vehicle. The crosslink transceiver is a 1/4 Watt transmitter

Study of Background Rejection Systems for the IXO Mission.

Science.gov (United States)

Laurent, Philippe; Limousin, O.; Tatischeff, V.

2009-01-01

The scientific performances of the IXO mission will necessitate a very low detector background level. This will imply thorough background simulations, and efficient background rejection systems. It necessitates also a very good knowledge of the detectors to be shielded. In APC, Paris, and CEA, Saclay, we got experience on these activities by conceiving and optimising in parallel the high energy detector and the active and passive background rejection system of the Simbol-X mission. Considering that this work may be naturally extended to other X-ray missions, we have initiated with CNES a R&D project on the study of background rejection systems mainly in view the IXO project. We will detail this activity in the poster.

EUCLID mission design

Science.gov (United States)

Wallner, Oswald; Ergenzinger, Klaus; Tuttle, Sean; Vaillon, L.; Johann, Ulrich

2017-11-01

EUCLID, a medium-class mission candidate of ESA's Cosmic Vision 2015-2025 Program, currently in Definition Phase (Phase A/B1), shall map the geometry of the Dark Universe by investigating dark matter distributions, the distance-redshift relationship, and the evolution of cosmic structures. EUCLID consists of a 1.2 m telescope and two scientific instruments for ellipticity and redshift measurements in the visible and nearinfrared wavelength regime. We present a design concept of the EUCLID mission which is fully compliant with the mission requirements. Preliminary concepts of the spacecraft and of the payload including the scientific instruments are discussed.

JUPITER’S PHASE VARIATIONS FROM CASSINI : A TESTBED FOR FUTURE DIRECT-IMAGING MISSIONS

International Nuclear Information System (INIS)

Mayorga, L. C.; Jackiewicz, J.; Rages, K.; West, R. A.; Knowles, B.; Lewis, N.; Marley, M. S.

2016-01-01

We present empirical phase curves of Jupiter from ∼0° to 140° as measured in multiple optical bandpasses by Cassini /Imaging Science Subsystem (ISS) during the Millennium flyby of Jupiter in late 2000 to early 2001. Phase curves are of interest for studying the energy balance of Jupiter and understanding the scattering behavior of the planet as an exoplanet analog. We find that Jupiter is significantly darker at partial phases than an idealized Lambertian planet by roughly 25% and is not well fit by Jupiter-like exoplanet atmospheric models across all wavelengths. We provide analytic fits to Jupiter’s phase function in several Cassini /ISS imaging filter bandpasses. In addition, these observations show that Jupiter’s color is more variable with phase angle than predicted by models. Therefore, the color of even a near Jupiter-twin planet observed at a partial phase cannot be assumed to be comparable to that of Jupiter at full phase. We discuss how the Wide-Field Infrared Survey Telescope and other future direct-imaging missions can enhance the study of cool giants.

48 CFR 1852.246-70 - Mission Critical Space System Personnel Reliability Program.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Mission Critical Space... CONTRACT CLAUSES Texts of Provisions and Clauses 1852.246-70 Mission Critical Space System Personnel Reliability Program. As prescribed in 1846.370(a), insert the following clause: Mission Critical Space System...

Candidate Mission from Planet Earth control and data delivery system architecture

Science.gov (United States)

Shapiro, Phillip; Weinstein, Frank C.; Hei, Donald J., Jr.; Todd, Jacqueline

1992-01-01

Using a structured, experienced-based approach, Goddard Space Flight Center (GSFC) has assessed the generic functional requirements for a lunar mission control and data delivery (CDD) system. This analysis was based on lunar mission requirements outlined in GSFC-developed user traffic models. The CDD system will facilitate data transportation among user elements, element operations, and user teams by providing functions such as data management, fault isolation, fault correction, and link acquisition. The CDD system for the lunar missions must not only satisfy lunar requirements but also facilitate and provide early development of data system technologies for Mars. Reuse and evolution of existing data systems can help to maximize system reliability and minimize cost. This paper presents a set of existing and currently planned NASA data systems that provide the basic functionality. Reuse of such systems can have an impact on mission design and significantly reduce CDD and other system development costs.

Towards a Multi-Mission, Airborne Science Data System Environment

Science.gov (United States)

Crichton, D. J.; Hardman, S.; Law, E.; Freeborn, D.; Kay-Im, E.; Lau, G.; Oswald, J.

2011-12-01

NASA earth science instruments are increasingly relying on airborne missions. However, traditionally, there has been limited common infrastructure support available to principal investigators in the area of science data systems. As a result, each investigator has been required to develop their own computing infrastructures for the science data system. Typically there is little software reuse and many projects lack sufficient resources to provide a robust infrastructure to capture, process, distribute and archive the observations acquired from airborne flights. At NASA's Jet Propulsion Laboratory (JPL), we have been developing a multi-mission data system infrastructure for airborne instruments called the Airborne Cloud Computing Environment (ACCE). ACCE encompasses the end-to-end lifecycle covering planning, provisioning of data system capabilities, and support for scientific analysis in order to improve the quality, cost effectiveness, and capabilities to enable new scientific discovery and research in earth observation. This includes improving data system interoperability across each instrument. A principal characteristic is being able to provide an agile infrastructure that is architected to allow for a variety of configurations of the infrastructure from locally installed compute and storage services to provisioning those services via the "cloud" from cloud computer vendors such as Amazon.com. Investigators often have different needs that require a flexible configuration. The data system infrastructure is built on the Apache's Object Oriented Data Technology (OODT) suite of components which has been used for a number of spaceborne missions and provides a rich set of open source software components and services for constructing science processing and data management systems. In 2010, a partnership was formed between the ACCE team and the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) mission to support the data processing and data management needs

Systems engineering and integration as a foundation for mission engineering

OpenAIRE

Beam, David F.

2015-01-01

Approved for public release; distribution is unlimited This paper investigates the emerging term mission engineering through the framework of systems engineering and systems integration. Systems engineering concepts, processes, and methodologies are extrapolated for use in conjunction with a systems integration, life-cycle based framework to effect mission engineering. The specific systems engineering concepts of measures of effectiveness, performance and suitability are recommended as fou...

Review of hardware cost estimation methods, models and tools applied to early phases of space mission planning

Science.gov (United States)

Trivailo, O.; Sippel, M.; Şekercioğlu, Y. A.

2012-08-01

The primary purpose of this paper is to review currently existing cost estimation methods, models, tools and resources applicable to the space sector. While key space sector methods are outlined, a specific focus is placed on hardware cost estimation on a system level, particularly for early mission phases during which specifications and requirements are not yet crystallised, and information is limited. For the space industry, cost engineering within the systems engineering framework is an integral discipline. The cost of any space program now constitutes a stringent design criterion, which must be considered and carefully controlled during the entire program life cycle. A first step to any program budget is a representative cost estimate which usually hinges on a particular estimation approach, or methodology. Therefore appropriate selection of specific cost models, methods and tools is paramount, a difficult task given the highly variable nature, scope as well as scientific and technical requirements applicable to each program. Numerous methods, models and tools exist. However new ways are needed to address very early, pre-Phase 0 cost estimation during the initial program research and establishment phase when system specifications are limited, but the available research budget needs to be established and defined. Due to their specificity, for vehicles such as reusable launchers with a manned capability, a lack of historical data implies that using either the classic heuristic approach such as parametric cost estimation based on underlying CERs, or the analogy approach, is therefore, by definition, limited. This review identifies prominent cost estimation models applied to the space sector, and their underlying cost driving parameters and factors. Strengths, weaknesses, and suitability to specific mission types and classes are also highlighted. Current approaches which strategically amalgamate various cost estimation strategies both for formulation and validation

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Zambia

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Zambia. The IUREP Orientation Phase mission to Zambia estimates that the Speculative Resources of that country fall within the range of 33 000 and 100 000 tonnes uranium. The majority of these resources are believed to exist in the Karoo sediments. Other potentially favourable geological environments are the Precambrian Katanga sediments, as well as intrusive rocks of different chemical compositions and surficial duricrusts. Previous unofficial estimates of Zambia's Reasonably Assured Resources (RAR) and Estimated Additional Resources (EAR) are considered to be still valid: the total RAR amount to 6 000 tonnes uranium, located in Karoo (4 000 tonnes) and Katanga (2 000 tonnes) sediments, while the EAR are believed to total 4 000 tonnes being found only in Karoo sediments. The mission recommends that approximately US$ 40 million be spent on uranium exploration in Zambia over 10 years. The largest part of this expenditure would be for drilling, while the remainder should be spent on airborne and ground surveys, as well as on interpretative work on previous airborne data, Landsat imageries, etc. (author)

Small Business Innovation Research GRC Phase I, Phase II, and Post-Phase II Opportunity Assessment for 2015

Science.gov (United States)

Nguyen, Hung D.; Steele, Gynelle C.

2016-01-01

This report outlines the 2015 Small Business Innovation Research/Small Business Technology Transfer (SBIR/STTR) Phase I, Phase II, and Post-Phase II opportunity contract award results associated with NASA's Aeronautics Research Mission Directorate (ARMD), Human Exploration and Operations Mission Directorate (HEOMD), Science Mission Directorate (SMD), and Space Technology Mission Directorate (STMD) for NASA Glenn Research Center. The report also highlights the number of Phase I, Phase II, and Post-Phase II contracts awarded by mission directorate. The 2015 Phase I contract awards to companies in Ohio and their corresponding technologies are also discussed.

Water Recovery System Design to Accommodate Dormant Periods for Manned Missions

Science.gov (United States)

Tabb, David; Carter, Layne

2015-01-01

Future manned missions beyond lower Earth orbit may include intermittent periods of extended dormancy. Under the NASA Advanced Exploration System (AES) project, NASA personnel evaluated the viability of the ISS Water Recovery System (WRS) to support such a mission. The mission requirement includes the capability for life support systems to support crew activity, followed by a dormant period of up to one year, and subsequently for the life support systems to come back online for additional crewed missions. Dormancy could be a critical issue due to concerns with microbial growth or chemical degradation that might prevent water systems from operating properly when the crewed mission began. As such, it is critical that the water systems be designed to accommodate this dormant period. This paper details the results of this evaluation, which include identification of dormancy issues, results of testing performed to assess microbial stability of pretreated urine during dormancy periods, and concepts for updating to the WRS architecture and operational concepts that will enable the ISS WRS to support the dormancy requirement.

Establishment probability in newly founded populations

Directory of Open Access Journals (Sweden)

Gusset Markus

2012-06-01

Full Text Available Abstract Background Establishment success in newly founded populations relies on reaching the established phase, which is defined by characteristic fluctuations of the population’s state variables. Stochastic population models can be used to quantify the establishment probability of newly founded populations; however, so far no simple but robust method for doing so existed. To determine a critical initial number of individuals that need to be released to reach the established phase, we used a novel application of the “Wissel plot”, where –ln(1 – P0(t is plotted against time t. This plot is based on the equation P0t=1–c1e–ω1t, which relates the probability of extinction by time t, P0(t, to two constants: c1 describes the probability of a newly founded population to reach the established phase, whereas ω1 describes the population’s probability of extinction per short time interval once established. Results For illustration, we applied the method to a previously developed stochastic population model of the endangered African wild dog (Lycaon pictus. A newly founded population reaches the established phase if the intercept of the (extrapolated linear parts of the “Wissel plot” with the y-axis, which is –ln(c1, is negative. For wild dogs in our model, this is the case if a critical initial number of four packs, consisting of eight individuals each, are released. Conclusions The method we present to quantify the establishment probability of newly founded populations is generic and inferences thus are transferable to other systems across the field of conservation biology. In contrast to other methods, our approach disaggregates the components of a population’s viability by distinguishing establishment from persistence.

Understanding cost growth during operations of planetary missions: An explanation of changes

Science.gov (United States)

McNeill, J. F.; Chapman, E. L.; Sklar, M. E.

In the development of project cost estimates for interplanetary missions, considerable focus is generally given to the development of cost estimates for the development of ground, flight, and launch systems, i.e., Phases B, C, and D. Depending on the project team, efforts expended to develop cost estimates for operations (Phase E) may be relatively less rigorous than that devoted to estimates for ground and flight systems development. Furthermore, the project team may be challenged to develop a solid estimate of operations cost in the early stages of mission development, e.g., Concept Study Report or Systems Requirement Review (CSR/SRR), Preliminary Design Review (PDR), as mission specific peculiarities that impact cost may not be well understood. In addition, a methodology generally used to develop Phase E cost is engineering build-up, also known as “ grass roots” . Phase E can include cost and schedule risks that are not anticipated at the time of the major milestone reviews prior to launch. If not incorporated into the engineering build-up cost method for Phase E, this may translate into an estimation of the complexity of operations and overall cost estimates that are not mature and at worse, insufficient. As a result, projects may find themselves with thin reserves during cruise and on-orbit operations or project overruns prior to the end of mission. This paper examines a set of interplanetary missions in an effort to better understand the reasons for cost and staffing growth in Phase E. The method used in the study is discussed as well as the major findings summarized as the Phase E Explanation of Change (EoC). Research for the study entailed the review of project materials, including Estimates at Completion (EAC) for Phase E and staffing profiles, major project milestone reviews, e.g., CSR, PDR, Critical Design Review (CDR), the interviewing of select project and mission management, and review of Phase E replan materials. From this work, a detai- ed

The Earth Observing System (EOS) Ground System: Leveraging an Existing Operational Ground System Infrastructure to Support New Missions

Science.gov (United States)

Hardison, David; Medina, Johnny; Dell, Greg

2016-01-01

The Earth Observer System (EOS) was officially established in 1990 and went operational in December 1999 with the launch of its flagship spacecraft Terra. Aqua followed in 2002 and Aura in 2004. All three spacecraft are still operational and producing valuable scientific data. While all are beyond their original design lifetime, they are expected to remain viable well into the 2020s. The EOS Ground System is a multi-mission system based at NASA Goddard Space Flight Center that supports science and spacecraft operations for these three missions. Over its operational lifetime to date, the EOS Ground System has evolved as needed to accommodate mission requirements. With an eye towards the future, several updates are currently being deployed. Subsystem interconnects are being upgraded to reduce data latency and improve system performance. End-of-life hardware and operating systems are being replaced to mitigate security concerns and eliminate vendor support gaps. Subsystem hardware is being consolidated through the migration to Virtual Machine based platforms. While mission operations autonomy was not a design goal of the original system concept, there is an active effort to apply state-of-the-art products from the Goddard Mission Services Evolution Center (GMSEC) to facilitate automation where possible within the existing heritage architecture. This presentation will provide background information on the EOS ground system architecture and evolution, discuss latest improvements, and conclude with the results of a recent effort that investigated how the current system could accommodate a proposed new earth science mission.

Multimission nuclear electric propulsion system for outer planet exploration missions

International Nuclear Information System (INIS)

Mondt, J.F.

1981-01-01

A 100-kW reactor power system with a specific mass of 15 to 30 kg/kW/sub e/ and an electric thrust system with a specific mass of 5 to 10 kg/kW/sub e/ can be combined into a nuclear electric propulsion system. The system can be used for outer planet missions as well as earth orbital transfer vehicle missions. 5 refs

Feasibility study of modern airships, phase 1. Volume 1: Summary and mission analysis (tasks 2 and 4)

Science.gov (United States)

Bloetscher, F.

1975-01-01

The histroy, potential mission application, and designs of lighter-than-air (LTA) vehicles are researched and evaluated. Missions are identified to which airship vehicles are potentially suited. Results of the mission analysis are combined with the findings of a parametric analysis to formulate the mission/vehicle combinations recommended for further study. Current transportation systems are surveyed and potential areas of competition are identified as well as potential missions resulting from limitations of these systems. Potential areas of military usage are included.

Onboard autonomous mission re-planning for multi-satellite system

Science.gov (United States)

Zheng, Zixuan; Guo, Jian; Gill, Eberhard

2018-04-01

This paper presents an onboard autonomous mission re-planning system for Multi-Satellites System (MSS) to perform onboard re-planing in disruptive situations. The proposed re-planning system can deal with different potential emergency situations. This paper uses Multi-Objective Hybrid Dynamic Mutation Genetic Algorithm (MO-HDM GA) combined with re-planning techniques as the core algorithm. The Cyclically Re-planning Method (CRM) and the Near Real-time Re-planning Method (NRRM) are developed to meet different mission requirements. Simulations results show that both methods can provide feasible re-planning sequences under unforeseen situations. The comparisons illustrate that using the CRM is average 20% faster than the NRRM on computation time. However, by using the NRRM more raw data can be observed and transmitted than using the CRM within the same period. The usability of this onboard re-planning system is not limited to multi-satellite system. Other mission planning and re-planning problems related to autonomous multiple vehicles with similar demands are also applicable.

HPT Clearance Control: Intelligent Engine Systems-Phase 1

Science.gov (United States)

2005-01-01

The following work has been completed to satisfy the Phase I Deliverables for the "HPT Clearance Control" project under NASA GRC's "Intelligent Engine Systems" program: (1) Need for the development of an advanced HPT ACC system has been very clearly laid out, (2) Several existing and potential clearance control systems have been reviewed, (3) A scorecard has been developed to document the system, performance (fuel burn, range, payload, etc.), thermal, and mechanical characteristics of the existing clearance control systems, (4) Engine size and flight cycle selection for the advanced HPT ACC system has been reviewed with "large engine"/"long range mission" combination showing the most benefit, (5) A scoring criteria has been developed to tie together performance parameters for an objective, data driven comparison of competing systems, and (6) The existing HPT ACC systems have been scored based on this scoring system.

Integrated payload and mission planning, phase 3. Volume 3: Ground real-time mission operations

Science.gov (United States)

White, W. J.

1977-01-01

The payloads tentatively planned to fly on the first two Spacelab missions were analyzed to examine the cost relationships of providing mission operations support from onboard vs the ground-based Payload Operations Control Center (POCC). The quantitative results indicate that use of a POCC, with data processing capability, to support real-time mission operations is the most cost effective case.

A maintenance optimization model for mission-oriented systems based on Wiener degradation

International Nuclear Information System (INIS)

Guo, Chiming; Wang, Wenbin; Guo, Bo; Si, Xiaosheng

2013-01-01

Over the past few decades, condition-based maintenance (CBM) has attracted many researchers because of its effectiveness and practical significance. This paper deals with mission-oriented systems subject to gradual degradation modeled by a Wiener stochastic process within the context of CBM. For a mission-oriented system, the mission usually has constraints on availability/reliability, the opportunity for maintenance actions, and the monitoring type (continuous or discrete). Furthermore, in practice, a mission-oriented system may undertake some preventive maintenance (PM) and after such PM, the system may return to an intermediate state between an as-good-as new state and an as-bad-as old state, i.e., the PM is not perfect and only partially restores the system. However, very few CBM models integrated these mission constraints together with an imperfect nature of the PM into the course of optimizing the PM policy. This paper develops a model to optimize the PM policy in terms of the maintenance related cost jointly considering the mission constraints and the imperfect PM nature. A numerical example is presented to demonstrate the proposed model. The comparison with the simulated results and the sensitivity analysis show the usefulness of the optimization model for mission-oriented system maintenance presented in this paper.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Sudan. February-March 1981

International Nuclear Information System (INIS)

Kneupper, G.; Scivetti, N.

1981-01-01

The IUREP Orientation Phase Mission to the Democratic Republic of the Sudan believes that the Speculative Resources of the country might fall between 20,000 and 40,000 tonnes uranium and more. This indicates that the Speculative Resources of the Sudan could be significantly higher than previously estimated (7,500 tonnes uranium) by the NEA/IAEA Steering Group on the Uranium Resources - IUREP Phase I. The Government is willing to consider valid exploration programmes presented by prospective partners as long as they serve the interests of both parties. Within the general six-year (1977/78-1982/83) plan for development of the country's mineral resources, the Ministry of Energy and Mining has set up certain priorities which it would like to see expeditiously implemented: uranium exploration and production stands high on the list of priorities. On the basis of very limited information on regional geology and on previous exploration which was available to the Mission, it is estimated that the greatest potential for the Speculative Resources of possible economic significance will prove to occur in the following geological environments of the Sudan (Red Sea Hills area is not included): precambrian basement complex, palaeozoic-mesozoic-tertiary sedimentary basins and the tertiary to recent calcretes. The IUREP Orientation Phase Mission believes that some 20 Million US$ (very rough estimate) will be needed to (1) check the validity of the basic geological concepts formulated on the uranium potential of the selected areas, (2) accumulate diagnostic geological, geophysical, geochemical data indicative of a true uranium potential there, (3) study the basement complex rocks and the sedimentary formations at least on a broad structural-stratigraphic reconnaissance basis (a tremendous amount of valuable water drilling data has accumulated over the last years for some of the selected sedimentary basins) and (4) determine the most appropriate investigation techniques to be utilized

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Morocco

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author) [fr

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Morocco

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author)

A Virtual Social Support System for Long-Duration Space Exploration Missions, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Our overall goal is to enhance the overall behavior health and performance of personnel on (future potential) long-duration missions. We propose to use a local...

The planetary spatial data infrastructure for the OSIRIS-REx mission

Science.gov (United States)

DellaGiustina, D. N.; Selznick, S.; Nolan, M. C.; Enos, H. L.; Lauretta, D. S.

2017-12-01

The primary objective of the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission is to return a pristine sample of carbonaceous material from primitive asteroid (101955) Bennu. Understanding the geospatial context of Bennu is critical to choosing a sample-site and also linking the nature of the sample to the global properties of Bennu and the broader asteroid population. We established a planetary spatial data infrastructure (PSDI) support the primary objective of OSIRIS-REx. OSIRIS-REx is unique among planetary missions in that all remote sensing is performed to support the sample return objective. Prior to sampling, OSIRIS-REx will survey Bennu for nearly two years to select and document the most valuable primary and backup sample sites. During this period, the mission will combine coordinated observations from five science instruments into four thematic maps: deliverability, safety, sampleability, and scientific value. The deliverability map assesses the probability that the flight dynamics team can deliver the spacecraft to the desired location. The safety map indicates the probability that physical hazards are present at the sample-site. The sampleability map quantifies the probability that a sample can be successfully collected from the surface. Finally, the scientific value map shows the probability that the collected sample contains organics and volatiles and also places the sample site in a definitive geological context relative to Bennu's history. The OSIRIS-REx Science Processing and Operations Center (SPOC) serves as the operational PSDI for the mission. The SPOC is tasked with intake of all data from the spacecraft and other ground sources and assimilating these data into a single comprehensive system for processing and presentation. The SPOC centralizes all geographic data of Bennu in a relational database and ensures that standardization and provenance are maintained throughout proximity

Investigations on the binary systems of boron with chromium, columbium, nickel, and thorium, including a discussion of the Phase TiB in the titanium-boron system

Energy Technology Data Exchange (ETDEWEB)

Andersson, L H; Kiessling, R

1950-01-01

Investigations on the binary systems chromium-, columbium-, nickel-, and thorium-boron are reported. The titanium-boron system is discussed, and it is shown that the phase TiB, previously assumed to have zincblende structure, probably has a face-centered titanium lattice with boron in the octahedral interstices. In the chromium-boron system, the structure of the eta phase has been determined. It has the composition Cr/sub 3/B/sub 4/ and is isomorphous with Ta/sub 3/B/sub 4/ and Mn/sub 3/B/sub 4/. Some data for the delta phase are also given. For the columbium-boron system, a phase analysis has been carried out. The structures of three of the intermediary phases, CbB, Cb/sub 3/B/sub 2/, and CbB/sub 2/ (with extended homogeneity range), have been determined. They are isomorphous with corresponding phases of the tantalum-boron system. A brief phase analysis of the nickel-boron system showed the existence of a phase with lower boron content than Ni/sub 2/B, which has not been previously reported. In the thorium-boron system a new phase, probably with a complicated structure, was found with a boron content of about 50 at. %.

Mission environments for the Isotope Brayton Flight System (preliminary)

International Nuclear Information System (INIS)

1975-01-01

The mission environments for the Isotope Brayton Flight Systems (IBFS) are summarized. These are based on (1) those environments established for the MHW-RTG system in the LES 8/9 and Mariner J/S and (2) engineering projections of those likely to exit for the IBFS. The pre-launch environments address transportation, storage, handling and assembly (to spacecraft) and checkout, field transportation, and launch site operations. Launch environments address the Titan IIIC and Shuttle launch vehicles. Operational mission environments address normal space temperature and meteoroide environments. Special environments that may be applicable to DOD missions are not included. Accident environments address explosion and fire for the Titan IIIC and the Shuttle, reentry, earth impact and post impact

Multi-mission space science data processing systems - Past, present, and future

Science.gov (United States)

Stallings, William H.

1990-01-01

Packetized telemetry that is consistent with the international Consultative Committee for Space Data Systems (CCSDS) has been baselined for future NASA missions such as Space Station Freedom. Some experiences from past and present multimission systems are examined, including current experiences in implementing a CCSDS standard packetized data processing system, relative to the effectiveness of the multimission approach in lowering life cycle cost and the complexity of meeting new mission needs. It is shown that the continued effort toward standardization of telemetry and processing support will permit the development of multimission systems needed to meet the increased requirements of future NASA missions.

75 FR 11918 - Hewlett Pachard Company, Business Critical Systems, Mission Critical Business Software Division...

Science.gov (United States)

2010-03-12

... Pachard Company, Business Critical Systems, Mission Critical Business Software Division, Openvms Operating... Colorado, Marlborough, Massachuetts; Hewlett Pachard Company, Business Critical Systems, Mission Critical... Company, Business Critical Systems, Mission Critical Business Software Division, OpenVMS Operating System...

Space Launch System (SLS) Mission Planner's Guide

Science.gov (United States)

Smith, David Alan

2017-01-01

The purpose of this Space Launch System (SLS) Mission Planner's Guide (MPG) is to provide future payload developers/users with sufficient insight to support preliminary SLS mission planning. Consequently, this SLS MPG is not intended to be a payload requirements document; rather, it organizes and details SLS interfaces/accommodations in a manner similar to that of current Expendable Launch Vehicle (ELV) user guides to support early feasibility assessment. Like ELV Programs, once approved to fly on SLS, specific payload requirements will be defined in unique documentation.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Turkey. September to November 1980

International Nuclear Information System (INIS)

Ziehr, H.; Komura, A.

1985-02-01

The IUREP Orientation Phase Mission to Turkey estimates the Speculative Resources of the country to lie between 21 000 and 55 000 tonnes uranium. Past exploration in Turkey, dating from 1953, has indicated a very high number of uranium occurrences and radioactive anomalies, but ore deposits of significant size and grade have not been found. Present reserves amount to 4 600 tonnes uranium which can be allocated to approximately 15 sandstone type deposits in Neogene continental sediments. Several hundreds of other occurrences and radioactive anomalies exist where ore reserves have not been delineated. The uranium occurrences and radioactive anomalies can be divided according to host rock into (a) crystalline massif and (b) Tertiary continental sediment. The greatest geological potential for further resources is estimated to exist in the above mentioned two geological terrains. The most favourable geological potential exists in Neogene continental sedimentary basins near the crystalline massifs. Because surface exploration in the known favourable areas such as the Koepruebasi Basin has been so systematic, extensive, and successful, it is improbable that additional surface work will have much effect in increasing the number of new radioactive anomalies or uranium occurrences detected at the surface in these areas. Surface survey work in these areas should be mainly designed to assist the understanding of structures at depth. Surface reconnaissance survey work is, however, required in other parts of the above mentioned two geological terrains in this country. Before starting such a reconnaissance survey in new areas, the Mission suggests that a careful and extensive library study be conducted in close co-operation with sedimentologists, petrologists, and remote sensing specialists. The Mission suggests that in the medium term, 8 to 10 years, some 85 - 110 million U.S. Dollars be spent on airborne and ground surveys, including geological, radiometric, geochemical, and

Scalable Integrated Multi-Mission Support System Simulator Release 3.0

Science.gov (United States)

Kim, John; Velamuri, Sarma; Casey, Taylor; Bemann, Travis

2012-01-01

The Scalable Integrated Multi-mission Support System (SIMSS) is a tool that performs a variety of test activities related to spacecraft simulations and ground segment checks. SIMSS is a distributed, component-based, plug-and-play client-server system useful for performing real-time monitoring and communications testing. SIMSS runs on one or more workstations and is designed to be user-configurable or to use predefined configurations for routine operations. SIMSS consists of more than 100 modules that can be configured to create, receive, process, and/or transmit data. The SIMSS/GMSEC innovation is intended to provide missions with a low-cost solution for implementing their ground systems, as well as significantly reducing a mission s integration time and risk.

Quality Assurance and T&E of Inertial Systems for RLV Mission

Science.gov (United States)

Sathiamurthi, S.; Thakur, Nayana; Hari, K.; Peter, Pilmy; Biju, V. S.; Mani, K. S.

2017-12-01

This work describes the quality assurance and Test and Evaluation (T&E) activities carried out for the inertial systems flown successfully in India's first reusable launch vehicle technology demonstrator hypersonic experiment mission. As part of reliability analysis, failure mode effect and criticality analysis and derating analysis were carried out in the initial design phase, findings presented to design review forums and the recommendations were implemented. T&E plan was meticulously worked out and presented to respective forums for review and implementation. Test data analysis, health parameter plotting and test report generation was automated and these automations significantly reduced the time required for these activities and helped to avoid manual errors. Further, T&E cycle is optimized without compromising on quality aspects. These specific measures helped to achieve zero defect delivery of inertial systems for RLV application.

Composable Mission Framework for Rapid End-to-End Mission Design and Simulation, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The innovation proposed here is the Composable Mission Framework (CMF) a model-based software framework that shall enable seamless continuity of mission design and...

BEARS: a multi-mission anomaly response system

Science.gov (United States)

Roberts, Bryce A.

2009-05-01

The Mission Operations Group at UC Berkeley's Space Sciences Laboratory operates a highly automated ground station and presently a fleet of seven satellites, each with its own associated command and control console. However, the requirement for prompt anomaly detection and resolution is shared commonly between the ground segment and all spacecraft. The efficient, low-cost operation and "lights-out" staffing of the Mission Operations Group requires that controllers and engineers be notified of spacecraft and ground system problems around the clock. The Berkeley Emergency Anomaly and Response System (BEARS) is an in-house developed web- and paging-based software system that meets this need. BEARS was developed as a replacement for an existing emergency reporting software system that was too closedsource, platform-specific, expensive, and antiquated to expand or maintain. To avoid these limitations, the new system design leverages cross-platform, open-source software products such as MySQL, PHP, and Qt. Anomaly notifications and responses make use of the two-way paging capabilities of modern smart phones.

Towards a new generation of mission planning systems: Flexibility and performance

Science.gov (United States)

Gasquet, A.; Parrod, Y.; Desaintvincent, A.

1994-01-01

This paper presents some new approaches which are required for a better adequacy of Mission Planning Systems. In particular, the performance flexibility and genericity issues are discussed based on experience acquired through various Mission Planning systems developed by Matra Marconi Space.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Thailand

International Nuclear Information System (INIS)

1985-01-01

The IURBP Orientation Phase Mission assesses the Speculative Uranium Resources in Thailand to be within the range of 1 500 to 38 500 tonnes U. Geological environments which are considered by the Mission to be favourable for uranium occurrences include the following: sandstones of Jurassic to Triassic age; Tertiary sedimentary basins (northern Thailand); Tertiary sedimentary basins (southern Thailand); associated with fluorite deposits; granitic rocks; black shales and graphitic slates of the Palaeozoic; associated with sedimentary phosphate deposits; and associated with monazite sands. Physical conditions in Thailand, including a wet tropical climate, dense forest growth and rugged terrain in some areas and relative inaccessibility, make exploration difficult and costly. There is currently no ready accessibility to detailed topographic and geological maps and other basic data. This lack of availability is a severe constraint to systematic exploration. The lack of skilled personnel experienced in uranium studies and the low level of technical support is a serious hindrance to exploration in Thailand. (author)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Cameroon

International Nuclear Information System (INIS)

1985-01-01

A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Cameroon. The IUREP Orientation Phase Mission to Cameroon estimates the Speculative Resources of that country to be in the order of 10 000 tonnes uranium for syenite-associated U-deposits in southern Cameroon, and in the order of 5 000 tonnes uranium for uranium deposits associated with albitized and desilicified late tectonic Panafrican granites (episyenite) and Paleozoic volcanics in northern Cameroon. No specific tonnage is given for Francevillian equivalents (DJA-Series) and for Mesozoic and Cenozoic sedimentary basins, which are thought to hold limited potential for sandstone hosted uranium. However the Douala basin, consisting of mixed marine and continental sequences merits some attention. No specific budget and programme for uranium exploration are proposed for Cameroon. Instead specific recommendations concerning specific potential environments and general recommendation concerning the methodology of exploration are made. (author)

Phase control of the probability of electronic transitions in the non-perturbative laser field intensity

International Nuclear Information System (INIS)

Yokoyama, Keiichi; Sugita, Akihiro; Yamada, Hidetaka; Teranishi, Yoshiaki; Yokoyama, Atsushi

2007-01-01

A preparatory study on the quantum control of the selective transition K(4S 1/2 ) → K(4P J ) (J=1/2, 3/2) in intense laser field is reported. To generate high average power femtosecond laser pulses with enough field intensity, a Ti:Sapphire regenerative amplifier system with a repetition rate of 1 kHz is constructed. The bandwidth and pulse energy are shown to qualify the required values for the completely selective transition with 100% population inversion. A preliminary experiment of the selective excitation shows that the fringe pattern formed by a phase related pulse pair depends on the laser intensity, indicating that the perturbative behavior of the excitation probabilities is not valid any more and the laser intensity reaches a non-perturbative region. (author)

Safety Characteristics in System Application of Software for Human Rated Exploration Missions for the 8th IAASS Conference

Science.gov (United States)

Mango, Edward J.

2016-01-01

system will launch only one mission per year even less during its developmental phases. Finally, the third is the partnered approach through the use of many different prime contractors, including commercial and international partners, to design and build the exploration systems. These three factors make the challenges to meet the mission preparations and the safety expectations extremely difficult to implement. As NASA leads a team of partners in the exploration beyond earth's influence, it is a safety imperative that the application software used to test, checkout, prepare and launch the exploration systems put safety of the hardware and mission first. Software safety characteristics are built into the design and development process to enable the human rated systems to begin their missions safely and successfully. Exploration missions beyond Earth are inherently risky, however, with solid safety approaches in both hardware and software, the boldness of these missions can be realized for all on the home planet.

Life Support Filtration System Trade Study for Deep Space Missions

Science.gov (United States)

Agui, Juan H.; Perry, Jay L.

2017-01-01

The National Aeronautics and Space Administrations (NASA) technical developments for highly reliable life support systems aim to maximize the viability of long duration deep space missions. Among the life support system functions, airborne particulate matter filtration is a significant driver of launch mass because of the large geometry required to provide adequate filtration performance and because of the number of replacement filters needed to a sustain a mission. A trade analysis incorporating various launch, operational and maintenance parameters was conducted to investigate the trade-offs between the various particulate matter filtration configurations. In addition to typical launch parameters such as mass, volume and power, the amount of crew time dedicated to system maintenance becomes an increasingly crucial factor for long duration missions. The trade analysis evaluated these parameters for conventional particulate matter filtration technologies and a new multi-stage particulate matter filtration system under development by NASAs Glenn Research Center. The multi-stage filtration system features modular components that allow for physical configuration flexibility. Specifically, the filtration system components can be configured in distributed, centralized, and hybrid physical layouts that can result in considerable mass savings compared to conventional particulate matter filtration technologies. The trade analysis results are presented and implications for future transit and surface missions are discussed.

Improved Traceability of Mission Concept to Requirements Using Model Based Systems Engineering

Science.gov (United States)

Reil, Robin

2014-01-01

Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the traditional document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This thesis presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magics MagicDraw modeling tool. The model incorporates mission concept and requirement information from the missions original DBSE design efforts. Active dependency relationships are modeled to analyze the completeness and consistency of the requirements to the mission concept. Overall experience and methodology are presented for both the MBSE and original DBSE design efforts of SporeSat.

A decision model for planetary missions

Science.gov (United States)

Hazelrigg, G. A., Jr.; Brigadier, W. L.

1976-01-01

Many techniques developed for the solution of problems in economics and operations research are directly applicable to problems involving engineering trade-offs. This paper investigates the use of utility theory for decision making in planetary exploration space missions. A decision model is derived that accounts for the objectives of the mission - science - the cost of flying the mission and the risk of mission failure. A simulation methodology for obtaining the probability distribution of science value and costs as a function spacecraft and mission design is presented and an example application of the decision methodology is given for various potential alternatives in a comet Encke mission.

Atmosphere composition monitor for space station and advanced missions application

International Nuclear Information System (INIS)

Wynveen, R.A.; Powell, F.T.

1987-01-01

Long-term human occupation of extraterrestrial locations may soon become a reality. The National Aeronautics and Space Administration (NASA) has recently completed the definition and preliminary design of the low earth orbit (LEO) space station. They are now currently moving into the detailed design and fabrication phase of this space station and are also beginning to analyze the requirements of several future missions that have been identified. These missions include, for example, Lunar and Mars sorties, outposts, bases, and settlements. A requirement of both the LEO space station and future missions are environmental control and life support systems (ECLSS), which provide a comfortable environment for humans to live and work. The ECLSS consists of several major systems, including atmosphere revitalization system (ARS), atmosphere pressure and composition control system, temperature and humidity control system, water reclamation system, and waste management system. Each of these major systems is broken down into subsystems, assemblies, units, and instruments. Many requirements and design drivers are different for the ECLSS of the LEO space station and the identified advanced missions (e.g., longer mission duration). This paper discusses one of the ARS assemblies, the atmosphere composition monitor assembly (ACMA), being developed for the LEO space station and addresses differences that will exist for the ACMA of future missions

IXV re-entry demonstrator: Mission overview, system challenges and flight reward

Science.gov (United States)

Angelini, Roberto; Denaro, Angelo

2016-07-01

The Intermediate eXperimental Vehicle (IXV) is an advanced re-entry demonstrator vehicle aimed to perform in-flight experimentation of atmospheric re-entry enabling systems and technologies. The IXV integrates key technologies at the system level, with significant advancements on Europe's previous flying test-beds. The project builds on previous achievements at system and technology levels, and provides a unique and concrete way of establishing and consolidating Europe's autonomous position in the strategic field of atmospheric re-entry. The IXV mission and system objectives are the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled reentry system, integrating critical re-entry technologies at system level. Among such critical technologies of interest, special attention is paid to aerodynamic and aerothermodynamics experimentation, including advanced instrumentation for aerothermodynamics phenomena investigations, thermal protections and hot-structures, guidance, navigation and flight control through combined jets and aerodynamic surfaces (i.e. flaps), in particular focusing on the technologies integration at system level for flight. Following the extensive detailed design, manufacturing, qualification, integration and testing of the flight segment and ground segment elements, IXV has performed a full successful flight on February 11th 2015. After the launch with the VEGA launcher form the CSG spaceport in French Guyana, IXV has performed a full nominal mission ending with a successful splashdown in the Pacific Ocean. During Flight Phase, the IXV space and ground segments worked perfectly, implementing the whole flight program in line with the commanded maneuvers and trajectory prediction, performing an overall flight of 34.400 km including 7.600 km with hot atmospheric re-entry in automatic guidance, concluding with successful precision landing at a distance of ~1

Tank waste remediation system retrieval and disposal mission readiness-to-proceed guidance and requirements to deliverables crosswalk

International Nuclear Information System (INIS)

Hall, C.E.

1998-01-01

Before RL can authorize proceeding with Phase 1B, the PHMC team must demonstrate its readiness to retrieve and deliver the waste to the private contractors and to receive and dispose of the products and byproducts returned from the treatment. The PHMC team has organized their plans for providing these vitrification-support services into the Retrieval and Disposal Mission within the Tank Waste Remediation System (TWRS) Program

Missions to Venus

Science.gov (United States)

Titov, D. V.; Baines, K. H.; Basilevsky, A. T.; Chassefiere, E.; Chin, G.; Crisp, D.; Esposito, L. W.; Lebreton, J.-P.; Lellouch, E.; Moroz, V. I.; Nagy, A. F.; Owen, T. C.; Oyama, K.-I.; Russell, C. T.; Taylor, F. W.; Young, R. E.

2002-10-01

Venus has always been a fascinating objective for planetary studies. At the beginning of the space era Venus became one of the first targets for spacecraft missions. Our neighbour in the solar system and, in size, the twin sister of Earth, Venus was expected to be very similar to our planet. However, the first phase of Venus spacecraft exploration in 1962-1992 by the family of Soviet Venera and Vega spacecraft and US Mariner, Pioneer Venus, and Magellan missions discovered an entirely different, exotic world hidden behind a curtain of dense clouds. These studies gave us a basic knowledge of the conditions on the planet, but generated many more questions concerning the atmospheric composition, chemistry, structure, dynamics, surface-atmosphere interactions, atmospheric and geological evolution, and the plasma environment. Despite all of this exploration by more than 20 spacecraft, the "morning star" still remains a mysterious world. But for more than a decade Venus has been a "forgotten" planet with no new missions featuring in the plans of the world space agencies. Now we are witnessing the revival of interest in this planet: the Venus Orbiter mission is approved in Japan, Venus Express - a European orbiter mission - has successfully passed the selection procedure in ESA, and several Venus Discovery proposals are knocking at the doors of NASA. The paper presents an exciting story of Venus spacecraft exploration, summarizes open scientific problems, and builds a bridge to the future missions.

Developing the NASA food system for long-duration missions.

Science.gov (United States)

Cooper, Maya; Douglas, Grace; Perchonok, Michele

2011-03-01

Even though significant development has transformed the space food system over the last 5 decades to attain more appealing dietary fare for low-orbit space crews, the advances do not meet the need for crews that might travel to Mars and beyond. It is estimated that a food system for a long-duration mission must maintain organoleptic acceptability, nutritional efficacy, and safety for a 3- to 5-y period to be viable. In addition, the current mass and subsequent waste of the food system must decrease significantly to accord with the allowable volume and payload limits of the proposed future space vehicles. Failure to provide the appropriate food or to optimize resource utilization introduces the risk that an inadequate food system will hamper mission success and/or threaten crew performance. Investigators for the National Aeronautics and Space Administration (NASA) Advanced Food Technology (AFT) consider identified concerns and work to mitigate the risks to ensure that any new food system is adequate for the mission. Yet, even with carefully planned research, some technological gaps remain. NASA needs research advances to develop food that is nutrient-dense and long-lasting at ambient conditions, partial gravity cooking processes, methods to deliver prescribed nutrients over time, and food packaging that meets the mass, barrier, and processing requirements of NASA. This article provides a brief review of research in each area, details the past AFT research efforts, and describes the remaining gaps that present barriers to achieving a food system for long exploration missions.

Dynamics of the Josephson multi-junction system with junctions characterized by non-sinusoidal current - phase relationship

International Nuclear Information System (INIS)

Abal'osheva, I.; Lewandowski, S.J.

2004-01-01

It is shown that the inclusion of junctions characterized by non-sinusoidal current - phase relationship in the systems composed of multiple Josephson junctions - results in the appearance of additional system phase states. Numerical simulations and stability considerations confirm that those phase states can be realized in practice. Moreover, spontaneous formation of the grain boundary junctions in high-T c superconductors with non-trivial current-phase relations due to the d-wave symmetry of the order parameter is probable. Switching between the phase states of multiple grain boundary junction systems can lead to additional 1/f noise in high-T c superconductors. (author)

India Mission System

Data.gov (United States)

US Agency for International Development — A monitoring system to help track IM level targets and roll them up to the element level for the purposes of the PPR. In subsequent phases will build in a GIS...

Dawn Mission Update

Science.gov (United States)

Sykes, M. V.; Russell, C. T.; Coradini, A.; Christensen, U.; de Sanctis, M. C.; Feldman, W. C.; Jaumann, R.; Keller, U.; Konopliv, A. S.; McCord, T. B.; McFadden, L. A.; McSween, H. Y.; Mottola, S.; Neukum, G.; Pieters, C. M.; Prettyman, T. H.; Raymond, C. A.; Smith, D. E.; Williams, B. G.; Wise, J.; Zuber, M. T.

2004-11-01

Dawn, the ninth Discovery mission, will be the first spacecraft to rendezvous with two solar system bodies, the main belt asteroids Vesta and Ceres. This is made possible by utilizing ion propulsion to reach its targets and to maneuver into (and depart) orbits about these bodies. Vesta and Ceres are two terrestrial protoplanets that have survived since the earliest epoch of the solar system and will provide important insights into planet building processes and their evolution under very different circumstances, with and without water. Dawn carries a double framing camera, a visible and infrared mapping spectrometer, and a gamma ray and neutron detector. At Vesta our studies will include the volcanic emplacement of basalts, its differentiation, the possible exposure of its interior near the south pole. At Ceres our studies will include the role of water in its evolution, hydration processes on its surface, and the possible existence of a subsurface ocean. The mission has passed its critical design review and is scheduled to be launched in June 2006 with arrival at Vesta in 2011 and Ceres in 2015. Operation strategies will be presented. Groundbased observations of Vesta, Ceres, and Vesta family members over broad wavelengths, periods and phases will play an important role in detailed mission planning.

SureTrak Probability of Impact Display

Science.gov (United States)

Elliott, John

2012-01-01

The SureTrak Probability of Impact Display software was developed for use during rocket launch operations. The software displays probability of impact information for each ship near the hazardous area during the time immediately preceding the launch of an unguided vehicle. Wallops range safety officers need to be sure that the risk to humans is below a certain threshold during each use of the Wallops Flight Facility Launch Range. Under the variable conditions that can exist at launch time, the decision to launch must be made in a timely manner to ensure a successful mission while not exceeding those risk criteria. Range safety officers need a tool that can give them the needed probability of impact information quickly, and in a format that is clearly understandable. This application is meant to fill that need. The software is a reuse of part of software developed for an earlier project: Ship Surveillance Software System (S4). The S4 project was written in C++ using Microsoft Visual Studio 6. The data structures and dialog templates from it were copied into a new application that calls the implementation of the algorithms from S4 and displays the results as needed. In the S4 software, the list of ships in the area was received from one local radar interface and from operators who entered the ship information manually. The SureTrak Probability of Impact Display application receives ship data from two local radars as well as the SureTrak system, eliminating the need for manual data entry.

NASA's OCA Mirroring System: An Application of Multiagent Systems in Mission Control

Science.gov (United States)

Sierhuis, Maarten; Clancey, William J.; vanHoof, Ron J. J.; Seah, Chin H.; Scott, Michael S.; Nado, Robert A.; Blumenberg, Susan F.; Shafto, Michael G.; Anderson, Brian L.; Bruins, Anthony C.;

Intelligent mobile sensor system for drum inspection and monitoring: Phase 1. Topical report, October 1, 1992--June 8, 1993

Energy Technology Data Exchange (ETDEWEB)

1993-06-01

The objective of this project was to develop an operational system for monitoring and inspection activities for waste storage facility operations at several DOE sites. Specifically, the product of this effort is a robotic device with enhanced intelligence and maneuverability capable of conducting routine inspection of stored waste drums. The device is capable of operating in narrow aisles and interpolating the free aisle space between rows of stacked drums. The system has an integrated sensor suite for leak detection, and is interfaced with a site database both for inspection planning and for data correlation, updating, and report generation. The system is capable of departing on an assigned mission, collecting required data, recording which positions of its mission had to be aborted or modified due to environmental constraints, and reporting back when the mission is complete. Successful identification of more than 90% of all drum defects has been demonstrated in a high fidelity waste storage facility mockup. Identified anomalies included rust spots, rust streaks, areas of corrosion, dents, and tilted drums. All drums were positively identified and correlated with the site database. This development effort is separated into three phases of which phase one is now complete. The first phase has demonstrated an integrated system for monitoring and inspection activities for waste storage facility operations. This demonstration system was quickly fielded and evaluated by leveraging technologies developed from previous NASA and DARPA contracts and internal research. The second phase will demonstrate a prototype system appropriate for operational use in an actual storage facility. The prototype provides an integrated design that considers operational requirements, hardware costs, maintenance, safety, and robustness. The final phase will demonstrate commercial viability using the prototype vehicle in a pilot waste operations and inspection project.

Technology assessment of advanced automation for space missions

Science.gov (United States)

1982-01-01

Six general classes of technology requirements derived during the mission definition phase of the study were identified as having maximum importance and urgency, including autonomous world model based information systems, learning and hypothesis formation, natural language and other man-machine communication, space manufacturing, teleoperators and robot systems, and computer science and technology.

Ruin probabilities

DEFF Research Database (Denmark)

Asmussen, Søren; Albrecher, Hansjörg

The book gives a comprehensive treatment of the classical and modern ruin probability theory. Some of the topics are Lundberg's inequality, the Cramér-Lundberg approximation, exact solutions, other approximations (e.g., for heavy-tailed claim size distributions), finite horizon ruin probabilities......, extensions of the classical compound Poisson model to allow for reserve-dependent premiums, Markov-modulation, periodicity, change of measure techniques, phase-type distributions as a computational vehicle and the connection to other applied probability areas, like queueing theory. In this substantially...... updated and extended second version, new topics include stochastic control, fluctuation theory for Levy processes, Gerber–Shiu functions and dependence....

Safeguarding a Lunar Rover with Wald's Sequential Probability Ratio Test

Science.gov (United States)

Furlong, Michael; Dille, Michael; Wong, Uland; Nefian, Ara

2016-01-01

The virtual bumper is a safeguarding mechanism for autonomous and remotely operated robots. In this paper we take a new approach to the virtual bumper system by using an old statistical test. By using a modified version of Wald's sequential probability ratio test we demonstrate that we can reduce the number of false positive reported by the virtual bumper, thereby saving valuable mission time. We use the concept of sequential probability ratio to control vehicle speed in the presence of possible obstacles in order to increase certainty about whether or not obstacles are present. Our new algorithm reduces the chances of collision by approximately 98 relative to traditional virtual bumper safeguarding without speed control.

Estimation of component failure probability from masked binomial system testing data

International Nuclear Information System (INIS)

Tan Zhibin

2005-01-01

The component failure probability estimates from analysis of binomial system testing data are very useful because they reflect the operational failure probability of components in the field which is similar to the test environment. In practice, this type of analysis is often confounded by the problem of data masking: the status of tested components is unknown. Methods in considering this type of uncertainty are usually computationally intensive and not practical to solve the problem for complex systems. In this paper, we consider masked binomial system testing data and develop a probabilistic model to efficiently estimate component failure probabilities. In the model, all system tests are classified into test categories based on component coverage. Component coverage of test categories is modeled by a bipartite graph. Test category failure probabilities conditional on the status of covered components are defined. An EM algorithm to estimate component failure probabilities is developed based on a simple but powerful concept: equivalent failures and tests. By simulation we not only demonstrate the convergence and accuracy of the algorithm but also show that the probabilistic model is capable of analyzing systems in series, parallel and any other user defined structures. A case study illustrates an application in test case prioritization

Ultra-Fast Flash Observatory: Fast Response Space Missions for Early Time Phase of Gamma Ray Bursts

DEFF Research Database (Denmark)

Park, I.H.; Ahmad, S.; Barrillon, P.

2013-01-01

One of the unexplored domains in the study of gamma-ray bursts (GRBs) is the early time phase of the optical light curve. We have proposed Ultra-Fast Flash Observatory (UFFO) to address this question through extraordinary opportunities presented by a series of small space missions. The UFFO...

Titan Orbiter Aerorover Mission with Enceladus Science (TOAMES)

Science.gov (United States)

Sittler, E.; Cooper, J.; Mahaffy, P.; Fairbrother, D.; de Pater, I.; Schulze-Makuch, D.; Pitman, J.

2007-08-01

organic chemistry on the surface. The Aerorover will probably use a "hot air" Montgolfier balloon concept using the waste heat from the MMRTG ~1-2 kwatts. New technologies will need to be developed and miniaturization will be required to maintain functionality while controlling mass, power and cost. Duty cycling will be used. The Aerorover will have all the instruments needed to sample Titan's atmosphere and surface with possible methane lakes-rivers. It will e.g., use multi-spectral imagers and for last 6 months of mission, balloon payload will land on surface at predetermined site to take core samples of the surface and use seismometers to help probe the interior. All remote (and active) sensors on the orbiter will share a ~1 meter telescope, called MIDAS (Multiple Instrument Distributed Aperture Sensor). MIDAS observations in stable orbit at Titan can provide full global maps of Titan's surface and could additionally provide long term observations of the Saturn system including Enceladus for extended mission phases over many years, potentially for decades. Experience from the Hubble Space Telescope has shown strong public interest and commitment to exciting generational missions.

Reliability assessment of single-phase grid-connected PV microinverters considering mission profile and uncertainties

DEFF Research Database (Denmark)

Zare, Mohammad Hadi; Mohamadian, Mustafa; Wang, Huai

2017-01-01

Microinverters usually connect a PV panel to a Single-phase power grid. In such system, the input power is constant while the output power oscillates twice the line frequency. Thus, the input and output power differences should be stored in a storage component, which is typically an electrolytic ...... irritation of two different places on the micro inverter lifetime is studied....... capacitor. However, electrolytic capacitors are usually blamed for their short lifetime. Recently, some active power decoupling methods are introduced in the literature which can takes advantage of high reliable film capacitors. However, some extra switches and diodes are added to the microinverter which...... can influence the microinverter lifetime. This paper investigates the microinverter reliability according to mission profile where it is installed. To get more accurate results, uncertainties in both lifetime model and manufacturing process are considered. The effect of ambient temperature and solar...

Calculation of magnetization curves and probability distribution for monoclinic and uniaxial systems

International Nuclear Information System (INIS)

Sobh, Hala A.; Aly, Samy H.; Yehia, Sherif

2013-01-01

We present the application of a simple classical statistical mechanics-based model to selected monoclinic and hexagonal model systems. In this model, we treat the magnetization as a classical vector whose angular orientation is dictated by the laws of equilibrium classical statistical mechanics. We calculate for these anisotropic systems, the magnetization curves, energy landscapes and probability distribution for different sets of relevant parameters and magnetic fields of different strengths and directions. Our results demonstrate a correlation between the most probable orientation of the magnetization vector, the system's parameters, and the external magnetic field. -- Highlights: ► We calculate magnetization curves and probability angular distribution of the magnetization. ► The magnetization curves are consistent with probability results for the studied systems. ► Monoclinic and hexagonal systems behave differently due to their different anisotropies

Titan Orbiter with Aerorover Mission (TOAM)

Science.gov (United States)

Sittler, Edward C.; Cooper, J. F.; Mahaffey, P.; Esper, J.; Fairbrother, D.; Farley, R.; Pitman, J.; Kojiro, D. R.; TOAM Team

2006-12-01

We propose to develop a new mission to Titan called Titan Orbiter with Aerorover Mission (TOAM). This mission is motivated by the recent discoveries of Titan, its atmosphere and its surface by the Huygens Probe, and a combination of in situ, remote sensing and radar mapping measurements of Titan by the Cassini orbiter. Titan is a body for which Astrobiology (i.e., prebiotic chemistry) will be the primary science goal of any future missions to it. TOAM is planned to use an orbiter and balloon technology (i.e., aerorover). Aerobraking will be used to put payload into orbit around Titan. The Aerorover will probably use a hot air balloon concept using the waste heat from the MMRTG 500 watts. Orbiter support for the Aerorover is unique to our approach for Titan. Our strategy to use an orbiter is contrary to some studies using just a single probe with balloon. Autonomous operation and navigation of the Aerorover around Titan will be required, which will include descent near to the surface to collect surface samples for analysis (i.e., touch and go technique). The orbiter can provide both relay station and GPS roles for the Aerorover. The Aerorover will have all the instruments needed to sample Titan’s atmosphere, surface, possible methane lakes-rivers, use multi-spectral imagers for surface reconnaissance; to take close up surface images; take core samples and deploy seismometers during landing phase. Both active and passive broadband remote sensing techniques will be used for surface topography, winds and composition measurements.

STS-61 mission director's post-mission report

Science.gov (United States)

Newman, Ronald L.

1995-01-01

To ensure the success of the complex Hubble Space Telescope servicing mission, STS-61, NASA established a number of independent review groups to assess management, design, planning, and preparation for the mission. One of the resulting recommendations for mission success was that an overall Mission Director be appointed to coordinate management activities of the Space Shuttle and Hubble programs and to consolidate results of the team reviews and expedite responses to recommendations. This report presents pre-mission events important to the experience base of mission management, with related Mission Director's recommendations following the event(s) to which they apply. All Mission Director's recommendations are presented collectively in an appendix. Other appendixes contain recommendations from the various review groups, including Payload Officers, the JSC Extravehicular Activity (EVA) Section, JSC EVA Management Office, JSC Crew and Thermal Systems Division, and the STS-61 crew itself. This report also lists mission events in chronological order and includes as an appendix a post-mission summary by the lead Payload Deployment and Retrieval System Officer. Recommendations range from those pertaining to specific component use or operating techniques to those for improved management, review, planning, and safety procedures.

Management and Systems Engineering of the Kepler Mission

Science.gov (United States)

Fanson, James; Livesay, Leslie; Frerking, Margaret; Cooke, Brian

2010-01-01

Kepler is the National Aeronautics and Space Administration's (NASA's) first mission capable of detecting Earth-size planets orbiting in the habitable zones around stars other than the sun. Selected for implementation in 2001 and launched in 2009, Kepler seeks to determine whether Earth-like planets are common or rare in the galaxy. The investigation requires a large, space-based photometer capable of simultaneously measuring the brightnesses of 100,000 stars at part-per-million level of precision. This paper traces the development of the mission from the perspective of project management and systems engineering and describes various methodologies and tools that were found to be effective. The experience of the Kepler development is used to illuminate lessons that can be applied to future missions.

Spacelab 3 mission

Science.gov (United States)

Dalton, Bonnie P.

1990-01-01

Spacelab-3 (SL-3) was the first microgravity mission of extended duration involving crew interaction with animal experiments. This interaction involved sharing the Spacelab environmental system, changing animal food, and changing animal waste trays by the crew. Extensive microbial testing was conducted on the animal specimens and crew and on their ground and flight facilities during all phases of the mission to determine the potential for cross contamination. Macroparticulate sampling was attempted but was unsuccessful due to the unforseen particulate contamination occurring during the flight. Particulate debris of varying size (250 micron to several inches) and composition was recovered post flight from the Spacelab floor, end cones, overhead areas, avionics fan filter, cabin fan filters, tunnel adaptor, and from the crew module. These data are discussed along with solutions, which were implemented, for particulate and microbial containment for future flight facilities.

Middleware Evaluation and Benchmarking for Use in Mission Operations Centers

Science.gov (United States)

Antonucci, Rob; Waktola, Waka

2005-01-01

Middleware technologies have been promoted as timesaving, cost-cutting alternatives to the point-to-point communication used in traditional mission operations systems. However, missions have been slow to adopt the new technology. The lack of existing middleware-based missions has given rise to uncertainty about middleware's ability to perform in an operational setting. Most mission architects are also unfamiliar with the technology and do not know the benefits and detriments to architectural choices - or even what choices are available. We will present the findings of a study that evaluated several middleware options specifically for use in a mission operations system. We will address some common misconceptions regarding the applicability of middleware-based architectures, and we will identify the design decisions and tradeoffs that must be made when choosing a middleware solution. The Middleware Comparison and Benchmark Study was conducted at NASA Goddard Space Flight Center to comprehensively evaluate candidate middleware products, compare and contrast the performance of middleware solutions with the traditional point- to-point socket approach, and assess data delivery and reliability strategies. The study focused on requirements of the Global Precipitation Measurement (GPM) mission, validating the potential use of middleware in the GPM mission ground system. The study was jointly funded by GPM and the Goddard Mission Services Evolution Center (GMSEC), a virtual organization for providing mission enabling solutions and promoting the use of appropriate new technologies for mission support. The study was broken into two phases. To perform the generic middleware benchmarking and performance analysis, a network was created with data producers and consumers passing data between themselves. The benchmark monitored the delay, throughput, and reliability of the data as the characteristics were changed. Measurements were taken under a variety of topologies, data demands

The Ion Propulsion System for the Asteroid Redirect Robotic Mission

Science.gov (United States)

Herman, Daniel A.; Santiago, Walter; Kamhawi, Hani; Polk, James E.; Snyder, John Steven; Hofer, Richard; Sekerak, Michael

2016-01-01

The Asteroid Redirect Robotic Mission is a Solar Electric Propulsion Technology Demonstration Mission (ARRM) whose main objectives are to develop and demonstrate a high-power solar electric propulsion capability for the Agency and return an asteroidal mass for rendezvous and characterization in a companion human-crewed mission. This high-power solar electric propulsion capability, or an extensible derivative of it, has been identified as a critical part of NASA's future beyond-low-Earth-orbit, human-crewed exploration plans. This presentation presents the conceptual design of the ARRM ion propulsion system, the status of the NASA in-house thruster and power processing development activities, the status of the planned technology maturation for the mission through flight hardware delivery, and the status of the mission formulation and spacecraft acquisition.

Multi-Mission MicroSDR, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Toyon proposes to develop a low-power and compact reconfigurable radio specifically targeted to NASA mission needs. We envision the radio to be well matched to small...

Reuniting the Solar System: Integrated Education and Public Outreach Projects for Solar System Exploration Missions and Programs

Science.gov (United States)

Lowes, Leslie; Lindstrom, Marilyn; Stockman, Stephanie; Scalice, Daniela; Klug, Sheri

2003-01-01

The Solar System Exploration Education Forum has worked for five years to foster Education and Public Outreach (E/PO) cooperation among missions and programs in order to leverage resources and better meet the needs of educators and the public. These efforts are coming together in a number of programs and products and in '2004 - The Year of the Solar System.' NASA's practice of having independent E/PO programs for each mission and its public affairs emphasis on uniqueness has led to a public perception of a fragmented solar system exploration program. By working to integrate solar system E/PO, the breadth and depth of the solar system exploration program is revealed. When emphasis is put on what missions have in common, as well as their differences, each mission is seen in the context of the whole program.

Rendezvous and Docking Strategy for Crewed Segment of the Asteroid Redirect Mission

Science.gov (United States)

Hinkel, Heather D.; Cryan, Scott P.; D'Souza, Christopher; Dannemiller, David P.; Brazzel, Jack P.; Condon, Gerald L.; Othon, William L.; Williams, Jacob

2014-01-01

This paper will describe the overall rendezvous, proximity operations and docking (RPOD) strategy in support of the Asteroid Redirect Crewed Mission (ARCM), as part of the Asteroid Redirect Mission (ARM). The focus of the paper is on the crewed mission phase of ARM, starting with the establishment of Orion in the Distant Retrograde Orbit (DRO) and ending with docking to the Asteroid Redirect Vechicle (ARV). The paper will detail the sequence of maneuvers required to execute the rendezvous and proximity operations mission phases along with the on-board navigation strategies, including the final approach phase. The trajectories to be considered will include target vehicles in a DRO. The paper will also discuss the sensor requirements for rendezvous and docking and the various trade studies associated with the final sensor selection. Building on the sensor requirements and trade studies, the paper will include a candidate sensor concept of operations, which will drive the selection of the sensor suite; concurrently, it will be driven by higher level requirements on the system, such as crew timeline constraints and vehicle consummables. This paper will address how many of the seemingly competing requirements will have to be addressed to create a complete system and system design. The objective is to determine a sensor suite and trajectories that enable Orion to successfully rendezvous and dock with a target vehicle in trans lunar space. Finally, the paper will report on the status of a NASA action to look for synergy within RPOD, across the crewed and robotic asteroid missions.

Loss-of-load probabilities for stand-alone photovoltaic systems

International Nuclear Information System (INIS)

Klein, S.A.; Beckman, W.A.

1989-01-01

A general method is presented for estimating the loss-of-load probability of stand-alone photovoltaic systems. The method was developed by correlating simulation results. The simulations were driven with synthetic radiation sequences having the same statistical significance as available historical data. The methods assumes a constant nighttime load and accounts for the distribution and persistence in daily solar radiation data. It is shown that the 10 year average performance of systems having loss-of-load probabilities less than about 0.01 can vary greatly from one ten year period to the next and thereby cannot be considered realistic performance estimates of a system during its lifetime. (author). 26 refs, 15 figs, 4 tabs

A comparison of propulsion systems for potential space mission applications

International Nuclear Information System (INIS)

Harvego, E.A.; Sulmeisters, T.K.

1987-01-01

A derivative of the NERVA nuclear rocket engine was compared with a chemical propulsion system and a nuclear electric propulsion system to assess the relative capabilities of the different propulsion system options for three potential space missions. The missions considered were (1) orbital transfer from low earth orbit (LEO) to geosynchronous earth orbit (GEO), (2) LEO to a lunar base, and (3) LEO to Mars. The results of this comparison indicate that the direct-thrust NERVA-derivative nuclear rocket engine has the best performance characteristics for the missions considered. The combined high thrust and high specific impulse achievable with a direct-thrust nuclear stage permits short operating times (transfer times) comparable to chemical propulsion systems, but with considerably less required propellant. While nuclear-electric propulsion systems are more fuel efficient than either direct-nuclear or chemical propulsion, they are not stand-alone systems, since their relatively low thrust levels require the use of high-thrust ferry or lander stages in high gravity applications such as surface-to-orbit propulsion. The extremely long transfer times and inefficient trajectories associated with electric propulsion systems were also found to be a significant drawback

FORMOSAT-3/COSMIC Spacecraft Constellation System, Mission Results, and Prospect for Follow-On Mission

Directory of Open Access Journals (Sweden)

Chen-Joe Fong

2009-01-01

Full Text Available The FORMOSAT-3/COSMIC spacecraft constellation consisting of six LEO satellites is the world's first operational GPS Radio Occultation (RO mission. The mission is jointly developed by Taiwan¡¦s National Space Organization (NSPO and the United States¡¦UCAR in collaboration with NSF, USAF, NOAA, NASA, NASA's Jet Propulsion Laboratory, and the US Naval Research Laboratory. The FORMOSAT-3/COSMIC satellites were successfully launched from Vandenberg US AFB in California at 0140 UTC 15 April 2006 into the same orbit plane of the designated 516 km altitude. The mission goal is to deploy the six satellites into six orbit planes at 800 km altitude with a 30-degree separation for evenly distributed global coverage. All six FORMOSAT-3/COSMIC satellites are currently maintaining a satisfactory good state-of-health. Five out of six satellites have reached their final mission orbit of 800 km as of November 2007. The data as received by FORMOSAT-3/COSMIC satellites constellation have been processed in near real time into 2500 good ionospheric profiles and 1800 good atmospheric profiles per day. These have outnumbered the worldwide radiosondes (~900 mostly over land launched from the ground per day. The processed atmospheric RO data have been assimilated into the Numerical Weather Prediction (NWP models for real-time weather prediction and typhoon/hurricane forecasting by many major weather centers in the world. This paper describes the FORMOSAT-3/COSMIC satellite constellation system performance and the mission results that span the period from April 2006 to October 2007; and reviews the prospect of a future follow-on mission.

Lean Mission Operations Systems Design - Using Agile and Lean Development Principles for Mission Operations Design and Development

Science.gov (United States)

Trimble, Jay Phillip

2014-01-01

The Resource Prospector Mission seeks to rove the lunar surface with an in-situ resource utilization payload in search of volatiles at a polar region. The mission operations system (MOS) will need to perform the short-duration mission while taking advantage of the near real time control that the short one-way light time to the Moon provides. To maximize our use of limited resources for the design and development of the MOS we are utilizing agile and lean methods derived from our previous experience with applying these methods to software. By using methods such as "say it then sim it" we will spend less time in meetings and more time focused on the one outcome that counts - the effective utilization of our assets on the Moon to meet mission objectives.

Attitude Ground System (AGS) for the Magnetospheric Multi-Scale (MMS) Mission

Science.gov (United States)

Raymond, Juan C.; Sedlak, Joseph E.; Vint, Babak

2015-01-01

MMS Overview Recall from Conrads presentation earlier today MMS launch: March 13, 2015 on an Atlas V from Space Launch Complex 40, Cape Canaveral, Florida MMS Observatory Separation: five minute intervals spinning at 3 rpm approximately 1.5 hours after launch MMS Science Goals: study magnetospheric plasma physics and understand the processes that cause power grids, communication disruptions and Aurora formation Mission: 4 identical spacecraft in tetrahedral formation with variable size1.2 x 12 RE in Phase 1, with apogee on dayside to observe bow shock1.2 x 25 RE in Phase 2, with apogee on night side to observe magneto tail Challenges Tight attitude control box, orbit and formation maintenance requirements Maneuvers on thrusters every two weeks Delta-H Spin axis direction and spin rate maintenance Delta-V Orbit and Formation maintenance Mission phase transitions AGS support Smart targeting prediction of Spin-Axis attitude in the presence of environmental torques to stay within the science attitude Determination of the spacecraft attitude and spin rate (sensitive to knowledge of inertia tensor)Calibrations to improve attitude determination results and improve orbit maneuvers Mass properties (Center of Mass, and inertia tensor for nutation and coning) Accelerometer bias (sensitive to the accuracy of the rate estimates) Sensor alignments.

Real-time data system: Incorporating new technology in mission critical environments

Science.gov (United States)

Muratore, John F.; Heindel, Troy A.

1990-01-01

If the Space Station Freedom is to remain viable over its 30-year life span, it must be able to incorporate new information systems technologies. These technologies are necessary to enhance mission effectiveness and to enable new NASA missions, such as supporting the Lunar-Mars Initiative. Hi-definition television (HDTV), neural nets, model-based reasoning, advanced languages, CPU designs, and computer networking standards are areas which have been forecasted to make major strides in the next 30 years. A major challenge to NASA is to bring these technologies online without compromising mission safety. In past programs, NASA managers have been understandably reluctant to rely on new technologies for mission critical activities until they are proven in noncritical areas. NASA must develop strategies to allow inflight confidence building and migration of technologies into the trusted tool base. NASA has successfully met this challenge and developed a winning strategy in the Space Shuttle Mission Control Center. This facility, which is clearly among NASA's most critical, is based on 1970's mainframe architecture. Changes to the mainframe are very expensive due to the extensive testing required to prove that changes do not have unanticipated impact on critical processes. Systematic improvement efforts in this facility have been delayed due to this 'risk to change.' In the real-time data system (RTDS) we have introduced a network of engineering computer workstations which run in parallel to the mainframe system. These workstations are located next to flight controller operating positions in mission control and, in some cases, the display units are mounted in the traditional mainframe consoles. This system incorporates several major improvements over the mainframe consoles including automated fault detection by real-time expert systems and color graphic animated schematics of subsystems driven by real-time telemetry. The workstations have the capability of recording

Computer graphics aid mission operations. [NASA missions

Science.gov (United States)

Jeletic, James F.

1990-01-01

The application of computer graphics techniques in NASA space missions is reviewed. Telemetric monitoring of the Space Shuttle and its components is discussed, noting the use of computer graphics for real-time visualization problems in the retrieval and repair of the Solar Maximum Mission. The use of the world map display for determining a spacecraft's location above the earth and the problem of verifying the relative position and orientation of spacecraft to celestial bodies are examined. The Flight Dynamics/STS Three-dimensional Monitoring System and the Trajectroy Computations and Orbital Products System world map display are described, emphasizing Space Shuttle applications. Also, consideration is given to the development of monitoring systems such as the Shuttle Payloads Mission Monitoring System and the Attitude Heads-Up Display and the use of the NASA-Goddard Two-dimensional Graphics Monitoring System during Shuttle missions and to support the Hubble Space Telescope.

Mars Internal Structure: Seismic Predictions for Core Phase Arrivals in Anticipation of the InSight Mission

Science.gov (United States)

Weber, R. C.; Banerdt, W. B.; Lognonne, P. H.; Hempel, S.; Panning, M. P.; Schmerr, N. C.; Garcia, R.; Shiro, B.; Gudkova, T.

2016-12-01

We present a methodology to constrain the seismic structure of the Martian core in preparation for the return of data from the InSight mission. Expected amplitudes for marsquakes assuming a medium seismicity model support the likely observation of core reflections of P and S energy for events with magnitude greater than MW 4.5. For the mission duration, we would expect to record on the order of 10 events of at least this magnitude. Our method predicts the ray density of core reflected (PcP, ScS) and transmitted (PKP, SKS) phases for various core sizes with core-mantle boundary depths between 1650 and 2100 km. Ray density is defined as the fraction of rays in a small source-receiver interval normalized by the total number of rays over a great circle slice through the planet. The ray density of a given phase is scaled by predicted amplitudes calculated considering attenuation, geometric spreading and reflection/transmission coefficients at discontinuities along the ray path. Maximum PcP/ScS amplitudes are expected at epicentral distances of 40-100 degrees. Thus, if present, strong seismicity in the Hellas and Tharsis region may facilitate core detection. For events with MW above 4.5, ScS and SKS signals are expected to lie above the lander noise, but PcP and PKP signals may barely be visible. The resolution of these phases can be improved by applying stacking techniques to account for expected background noise, scattering, and interfering seismic phases. These techniques were successfully applied to Apollo seismograms to infer the radial structure of the lunar core. Even if source depth and location have large uncertainties during a single-station mission to Mars, different phases can be distinguished by their slownesses. Prior to the summation of the traces of individual events, signals are aligned to a reference phase, e.g. the PcP onset assuming various core radii. A maximum in signal coherency corresponds to the best fitting core radius. In the case of lunar

Estimating reliability of degraded system based on the probability density evolution with multi-parameter

Directory of Open Access Journals (Sweden)

Jiang Ge

2017-01-01

Full Text Available System degradation was usually caused by multiple-parameter degradation. The assessment result of system reliability by universal generating function was low accurate when compared with the Monte Carlo simulation. And the probability density function of the system output performance cannot be got. So the reliability assessment method based on the probability density evolution with multi-parameter was presented for complexly degraded system. Firstly, the system output function was founded according to the transitive relation between component parameters and the system output performance. Then, the probability density evolution equation based on the probability conservation principle and the system output function was established. Furthermore, probability distribution characteristics of the system output performance was obtained by solving differential equation. Finally, the reliability of the degraded system was estimated. This method did not need to discrete the performance parameters and can establish continuous probability density function of the system output performance with high calculation efficiency and low cost. Numerical example shows that this method is applicable to evaluate the reliability of multi-parameter degraded system.

Planning for Planetary Science Mission Including Resource Prospecting, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Advances in computer-aided mission planning can enhance mission operations and science return for surface missions to Mars, the Moon, and beyond. While the...

Developing a Formal Specification for the Mission Systems of a Maritime Surveillance Aircraft

DEFF Research Database (Denmark)

Petrucci, Laure; Billington, Jonathan; Kristensen, Lars Michael

2003-01-01

The mission system of an aircraft is a complex real-time distributed system consisting of a mission control computer, different kinds of devices interconnected by a number of serial data buses. The complexity and real-time requirements of mission systems have motivated research into the applicati...... system with Coloured Petri Nets and analysed the model using state spaces. Here, we describe how this model was refined and modified to obtain a Coloured Petri Net model for the AP-3C Orion maritime surveillance aircraft....

Phase change energy storage for solar dynamic power systems

Science.gov (United States)

Chiaramonte, F. P.; Taylor, J. D.

1992-01-01

This paper presents the results of a transient computer simulation that was developed to study phase change energy storage techniques for Space Station Freedom (SSF) solar dynamic (SD) power systems. Such SD systems may be used in future growth SSF configurations. Two solar dynamic options are considered in this paper: Brayton and Rankine. Model elements consist of a single node receiver and concentrator, and takes into account overall heat engine efficiency and power distribution characteristics. The simulation not only computes the energy stored in the receiver phase change material (PCM), but also the amount of the PCM required for various combinations of load demands and power system mission constraints. For a solar dynamic power system in low earth orbit, the amount of stored PCM energy is calculated by balancing the solar energy input and the energy consumed by the loads corrected by an overall system efficiency. The model assumes an average 75 kW SD power system load profile which is connected to user loads via dedicated power distribution channels. The model then calculates the stored energy in the receiver and subsequently estimates the quantity of PCM necessary to meet peaking and contingency requirements. The model can also be used to conduct trade studies on the performance of SD power systems using different storage materials.

Space qualification of an experimental two-phase flow thermal management system

International Nuclear Information System (INIS)

Koonmen, J.P.; Carswell, L.C.; Kvansnak, M.A.

1991-01-01

The Weapons Laboratory will launch a space experiment in March 1991 to investigate the effects of extended microgravity on two-phase (liquid/vapor) flow. The qualification process for the experimental flight system hardware differs significantly from the process used for complex, high cost, long life space systems. Some development, qualification, and acceptance tests normally included in the test program of an operational space system were omitted because of the low program cost and low consequence of experiment failure. Key environment and functional qualification tests were performed, however, in an effort to reduce the risk of failure inherent in any space mission. The environmental qualification program included short duration vacuum chamber tests, reduced gravity missions onboard a National Aeronautics and Space Administration (NASA) test aircraft, and a complete series of shock and vibration tests. The functional qualification program centered on thermal-hydraulic system performance tests and a complete check-out of the unique telemetry system used to retrieve the experimental data from the payload. The test program also contains a number of acceptance and prelaunch validation tests to be performed as final verification of payloads readiness for spaceflight

Game Changing: NASA's Space Launch System and Science Mission Design

Science.gov (United States)

Creech, Stephen D.

2013-01-01

NASA s Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will carry the Orion Multi-Purpose Crew Vehicle (MPCV) and other important payloads far beyond Earth orbit (BEO). Its evolvable architecture will allow NASA to begin with Moon fly-bys and then go on to transport humans or robots to distant places such as asteroids and Mars. Designed to simplify spacecraft complexity, the SLS rocket will provide improved mass margins and radiation mitigation, and reduced mission durations. These capabilities offer attractive advantages for ambitious missions such as a Mars sample return, by reducing infrastructure requirements, cost, and schedule. For example, if an evolved expendable launch vehicle (EELV) were used for a proposed mission to investigate the Saturn system, a complicated trajectory would be required - with several gravity-assist planetary fly-bys - to achieve the necessary outbound velocity. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will report, the SLS rocket will launch payloads of unprecedented mass and volume, such as "monolithic" telescopes and in-space infrastructure. Thanks to its ability to co-manifest large payloads, it also can accomplish complex missions in fewer launches. Future analyses will include reviews of alternate mission concepts and detailed evaluations of SLS figures of merit, helping the new rocket revolutionize science mission planning and design for years to come.

Report of the Secretary of Defense Task Force on DoD Nuclear Weapons Management. Phase II: Review of the DoD Nuclear Mission

National Research Council Canada - National Science Library

Schlesinger, James R; Carns, Michael P; Crouch, II, J. D; Gansler, Jacques S; Giambastiani, Jr., Edmund P; Hamre, John J; Miller, Franklin C; Williams, Christopher A; Blackwell, Jr, James A

2008-01-01

...). This report covers Phase II findings and recommendations. In Phase II, the Task Force found that the lack of interest in and attention to the nuclear mission and nuclear deterrence, as discussed in our Phase I report, go well beyond the Air...

MMPM - Mars MetNet Precursor Mission

Science.gov (United States)

Harri, A.-M.; Schmidt, W.; Pichkhadze, K.; Linkin, V.; Vazquez, L.; Uspensky, M.; Polkko, J.; Genzer, M.; Lipatov, A.; Guerrero, H.; Alexashkin, S.; Haukka, H.; Savijarvi, H.; Kauhanen, J.

2008-09-01

We are developing a new kind of planetary exploration mission for Mars - MetNet in situ observation network based on a new semi-hard landing vehicle called the Met-Net Lander (MNL). The eventual scope of the MetNet Mission is to deploy some 20 MNLs on the Martian surface using inflatable descent system structures, which will be supported by observations from the orbit around Mars. Currently we are working on the MetNet Mars Precursor Mission (MMPM) to deploy one MetNet Lander to Mars in the 2009/2011 launch window as a technology and science demonstration mission. The MNL will have a versatile science payload focused on the atmospheric science of Mars. Detailed characterization of the Martian atmospheric circulation patterns, boundary layer phenomena, and climatology cycles, require simultaneous in-situ measurements by a network of observation posts on the Martian surface. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. The MetNet mission concept and key probe technologies have been developed and the critical subsystems have been qualified to meet the Martian environmental and functional conditions. Prototyping of the payload instrumentation with final dimensions was carried out in 2003-2006.This huge development effort has been fulfilled in collaboration between the Finnish Meteorological Institute (FMI), the Russian Lavoschkin Association (LA) and the Russian Space Research Institute (IKI) since August 2001. Currently the INTA (Instituto Nacional de Técnica Aeroespacial) from Spain is also participating in the MetNet payload development. To understand the behavior and dynamics of the Martian atmosphere, a wealth of simultaneous in situ observations are needed on varying types of Martian orography, terrain and altitude spanning all latitudes and longitudes. This will be performed by the Mars MetNet Mission. In addition to the science aspects the

The Ulysses mission: An introduction

International Nuclear Information System (INIS)

Marsden, R.G.

1996-01-01

On 30 September 1995, Ulysses completed its initial, highly successful, survey of the polar regions of the heliosphere in both southern and northern hemispheres, thereby fulfilling its prime mission. The results obtained to date are leading to a revision of many earlier ideas concerning the solar wind and the heliosphere. Now embarking on the second phase of the mission, Ulysses will continue along its out-of-ecliptic flight path for another complete orbit of the Sun. In contrast to the high-latitude phase of the prime mission, which occurred near solar minimum, the next polar passes (in 2000 and 2001) will take place when the Sun is at its most active

Cyber Threat Assessment of Uplink and Commanding System for Mission Operation

Science.gov (United States)

Ko, Adans Y.; Tan, Kymie M. C.; Cilloniz-Bicchi, Ferner; Faris, Grant

2014-01-01

Most of today's Mission Operations Systems (MOS) rely on Ground Data System (GDS) segment to mitigate cyber security risks. Unfortunately, IT security design is done separately from the design of GDS' mission operational capabilities. This incoherent practice leaves many security vulnerabilities in the system without any notice. This paper describes a new way to system engineering MOS, to include cyber threat risk assessments throughout the MOS development cycle, without this, it is impossible to design a dependable and reliable MOS to meet today's rapid changing cyber threat environment.

Phases, phase equilibria, and phase rules in low-dimensional systems

International Nuclear Information System (INIS)

Frolov, T.; Mishin, Y.

2015-01-01

We present a unified approach to thermodynamic description of one, two, and three dimensional phases and phase transformations among them. The approach is based on a rigorous definition of a phase applicable to thermodynamic systems of any dimensionality. Within this approach, the same thermodynamic formalism can be applied for the description of phase transformations in bulk systems, interfaces, and line defects separating interface phases. For both lines and interfaces, we rigorously derive an adsorption equation, the phase coexistence equations, and other thermodynamic relations expressed in terms of generalized line and interface excess quantities. As a generalization of the Gibbs phase rule for bulk phases, we derive phase rules for lines and interfaces and predict the maximum number of phases than may coexist in systems of the respective dimensionality

Fast mission reliability prediction for Unmanned Aerial Vehicles

International Nuclear Information System (INIS)

Andrews, J.D.; Poole, J.; Chen, W.H.

2013-01-01

There is currently a significant interest in the use of autonomous vehicles in many industrial sectors. One such example is the ever increasing use of Unmanned Aerial Vehicles (UAVs), particularly in military operations. This enables dangerous missions to be accomplished without risk to a pilot. UAVs also have potential civil applications which would require their certification and the demonstration that they are able to respond safety to any potential circumstances. The aircraft would therefore need to be capable of responding safely to the occurrence of component failures, the emergence of threats such as other aircraft in the neighboring airspace, and changing weather conditions. The likelihood that an aircraft will successfully complete any mission can be predicted using phased mission analysis techniques. The predicted mission unreliability can be updated in response to changing circumstances. In the event that the likelihood of mission failure becomes too high then changes have to be made to the mission plan. If these calculations could be carried out fast enough then the quantification procedure could be used to establish an acceptable response to any new conditions. With a view to using the methodology in the context described above, this paper investigates ways in which phased mission analysis can be improved to reduce the calculation time. The methodology improves the processing capability for a UAV phased mission analysis by taking into account the specific characteristics of the fault tree structures which provide the causes of phase failure for a UAV mission. It also carries out as much of the quantification as possible in advance of the mission plan being formulated

NESTEM-QRAS: A Tool for Estimating Probability of Failure

Science.gov (United States)

Patel, Bhogilal M.; Nagpal, Vinod K.; Lalli, Vincent A.; Pai, Shantaram; Rusick, Jeffrey J.

2002-10-01

An interface between two NASA GRC specialty codes, NESTEM and QRAS has been developed. This interface enables users to estimate, in advance, the risk of failure of a component, a subsystem, and/or a system under given operating conditions. This capability would be able to provide a needed input for estimating the success rate for any mission. NESTEM code, under development for the last 15 years at NASA Glenn Research Center, has the capability of estimating probability of failure of components under varying loading and environmental conditions. This code performs sensitivity analysis of all the input variables and provides their influence on the response variables in the form of cumulative distribution functions. QRAS, also developed by NASA, assesses risk of failure of a system or a mission based on the quantitative information provided by NESTEM or other similar codes, and user provided fault tree and modes of failure. This paper will describe briefly, the capabilities of the NESTEM, QRAS and the interface. Also, in this presentation we will describe stepwise process the interface uses using an example.

NESTEM-QRAS: A Tool for Estimating Probability of Failure

Science.gov (United States)

Patel, Bhogilal M.; Nagpal, Vinod K.; Lalli, Vincent A.; Pai, Shantaram; Rusick, Jeffrey J.

2002-01-01

An interface between two NASA GRC specialty codes, NESTEM and QRAS has been developed. This interface enables users to estimate, in advance, the risk of failure of a component, a subsystem, and/or a system under given operating conditions. This capability would be able to provide a needed input for estimating the success rate for any mission. NESTEM code, under development for the last 15 years at NASA Glenn Research Center, has the capability of estimating probability of failure of components under varying loading and environmental conditions. This code performs sensitivity analysis of all the input variables and provides their influence on the response variables in the form of cumulative distribution functions. QRAS, also developed by NASA, assesses risk of failure of a system or a mission based on the quantitative information provided by NESTEM or other similar codes, and user provided fault tree and modes of failure. This paper will describe briefly, the capabilities of the NESTEM, QRAS and the interface. Also, in this presentation we will describe stepwise process the interface uses using an example.

Missions and planning for nuclear space power

International Nuclear Information System (INIS)

Buden, D.

1979-01-01

Requirements for electrical and propulsion power for space are expected to increase dramatically in the 1980s. Nuclear power is probably the only source for some deep space missions and a major competitor for many orbital missions, especially those at geosynchronous orbit. Because of the potential requirements, a technology program on reactor components has been initiated by the Department of Energy. The missions that are foreseen, the current reactor concept, and the technology program plan are described

Microservices: Migration of a Mission Critical System

OpenAIRE

Dragoni, Nicola; Dustdar, Schahram; Larsen, Stephan T.; Mazzara, Manuel

2017-01-01

The microservices paradigm aims at changing the way in which software is perceived, conceived and designed. One of the foundational characteristics of this new promising paradigm, compared for instance to monolithic architectures, is scalability. In this paper, we present a real world case study in order to demonstrate how scalability is positively affected by re-implementing a monolithic architecture into microservices. The case study is based on the FX Core system, a mission critical system...

The system design of TRIO cinema Mission

Science.gov (United States)

Jin, Ho; Seon, Jongho; Kim, Khan-Hyuk; Lee, Dong-Hun; Kim, Kap-Sung; Lin, Robert; Parks, George; Tindall, Craig; Horbury, T. S.; Larson, Davin; Sample, John

TRIO (Triplet Ionospheric Observatory) CINEMA ( Cubesat for Ion, Neutral, Electron, MAg-netic fields) is a space science mission with three identical cubesats. The main scientific objec-tives are a multi-observation of ionospheric ENA (Energetic Neutral Atom) imaging, ionospheric signature of suprathermal electrons and ions and complementary measurements of magnetic fields for particle data. For this, Main payloads consist of a suprathermal electron, ion, neutral (STEIN) instrument and a 3-axis magnetometer of magnetoresistive sensors. The CINEMA is a 3-unit CubeSat, which translates to a 10 cm x 10 cm x 30 cm in volume and no more than four kilograms in mass. An attitude control system (ACS) uses torque coils, a sun sensor and the magnetometers and spin CINEMA spcaecraft 4 rpm with the spin axis perpendicular to the ecliptic plane. CINEMA will be placed into a high inclination low earth orbit that crosses the auroral zone and cusp. Three institutes are collaborating to develop CINEMA cubesats: i) two cubesats by Kyung Hee University (KHU) under their World Class University (WCU) program, ii) one cubesat by UC Berkeley under the NSF support, and iii) three magnetometers are provide by Imperial College, respectively. In this paper, we describe the system design and their performance of TR IO cinema mission. TRIO cinema's development of miniature in-strument and spacecraft spinning operation will play an important role for future nanosatellite space missions

ICPP - a collision probability module for the AUS neutronics code system

International Nuclear Information System (INIS)

Robinson, G.S.

1985-10-01

The isotropic collision probability program (ICPP) is a module of the AUS neutronics code system which calculates first flight collision probabilities for neutrons in one-dimensional geometries and in clusters of rods. Neutron sources, including scattering, are assumed to be isotropic and to be spatially flat within each mesh interval. The module solves the multigroup collision probability equations for eigenvalue or fixed source problems

Preparing and Conducting Review Missions of Instrumentation and Control Systems in Nuclear Power Plants

International Nuclear Information System (INIS)

2016-07-01

The IERICS (Independent Engineering Review of Instrumentation and Control Systems) mission is a comprehensive engineering review service directly addressing strategy and the key elements for implementation of modern instrumentation and control (I&C) systems, noting in applicable cases, specific concerns related to the implementation of advanced digital I&C systems and the use of software and/or digital logic in safety applications of a nuclear power plant. The guidelines outlined in this publication provide a basic structure, common reference and checklist across the various areas covered by an IERICS mission. Publications referenced in these guidelines could provide additional useful information for the counterpart while preparing for the IERICS mission. A structure for the mission report is given in the Appendix. In 2016, this publication was revised by international experts who had participated in previous IERICS missions. The revision reflects experiences and lessons learned from the preparation and conduct of those missions

System Geometries and Transit/Eclipse Probabilities

Directory of Open Access Journals (Sweden)

Howard A.

2011-02-01

Full Text Available Transiting exoplanets provide access to data to study the mass-radius relation and internal structure of extrasolar planets. Long-period transiting planets allow insight into planetary environments similar to the Solar System where, in contrast to hot Jupiters, planets are not constantly exposed to the intense radiation of their parent stars. Observations of secondary eclipses additionally permit studies of exoplanet temperatures and large-scale exo-atmospheric properties. We show how transit and eclipse probabilities are related to planet-star system geometries, particularly for long-period, eccentric orbits. The resulting target selection and observational strategies represent the principal ingredients of our photometric survey of known radial-velocity planets with the aim of detecting transit signatures (TERMS.

IUS/TUG orbital operations and mission support study. Volume 4: Project planning data

Science.gov (United States)

1975-01-01

Planning data are presented for the development phases of interim upper stage (IUS) and tug systems. Major project planning requirements, major event schedules, milestones, system development and operations process networks, and relevant support research and technology requirements are included. Topics discussed include: IUS flight software; tug flight software; IUS/tug ground control center facilities, personnel, data systems, software, and equipment; IUS mission events; tug mission events; tug/spacecraft rendezvous and docking; tug/orbiter operations interface, and IUS/orbiter operations interface.

Fundamental performance determining factors of the ultrahigh-precision space-borne optical metrology system for the LISA Pathfinder mission

Science.gov (United States)

Hechenblaikner, Gerald; Flatscher, Reinhold

2013-05-01

The LISA Pathfinder mission to space employs an optical metrology system (OMS) at its core to measure the distance and attitude between two freely floating test-masses to picometer and nanorad accuracy, respectively, within the measurement band of [1 mHz, 30 mHz]. The OMS is based upon an ultra-stable optical bench with 4 heterodyne interferometers from which interference signals are read-out and processed by a digital phase-meter. Laser frequency noise, power fluctuations and optical path-length variations are suppressed to uncritical levels by dedicated control loops so that the measurement performance approaches the sensor limit imposed by the phasemeter. The system design is such that low frequency common mode noise which affects the read-out phase of all four interferometers is generally well suppressed by subtraction of a reference phase from the other interferometer signals. However, high frequency noise directly affects measurement performance and its common mode rejection depends strongly on the relative signal phases. We discuss how the data from recent test campaigns point towards high frequency phase noise as a likely performance limiting factor which explains some important performance features.

Mission Management Computer and Sequencing Hardware for RLV-TD HEX-01 Mission

Science.gov (United States)

Gupta, Sukrat; Raj, Remya; Mathew, Asha Mary; Koshy, Anna Priya; Paramasivam, R.; Mookiah, T.

2017-12-01

Reusable Launch Vehicle-Technology Demonstrator Hypersonic Experiment (RLV-TD HEX-01) mission posed some unique challenges in the design and development of avionics hardware. This work presents the details of mission critical avionics hardware mainly Mission Management Computer (MMC) and sequencing hardware. The Navigation, Guidance and Control (NGC) chain for RLV-TD is dual redundant with cross-strapped Remote Terminals (RTs) interfaced through MIL-STD-1553B bus. MMC is Bus Controller on the 1553 bus, which does the function of GPS aided navigation, guidance, digital autopilot and sequencing for the RLV-TD launch vehicle in different periodicities (10, 20, 500 ms). Digital autopilot execution in MMC with a periodicity of 10 ms (in ascent phase) is introduced for the first time and successfully demonstrated in the flight. MMC is built around Intel i960 processor and has inbuilt fault tolerance features like ECC for memories. Fault Detection and Isolation schemes are implemented to isolate the failed MMC. The sequencing hardware comprises Stage Processing System (SPS) and Command Execution Module (CEM). SPS is `RT' on the 1553 bus which receives the sequencing and control related commands from MMCs and posts to downstream modules after proper error handling for final execution. SPS is designed as a high reliability system by incorporating various fault tolerance and fault detection features. CEM is a relay based module for sequence command execution.

Why Mission-Critical Systems Are Critical to the Future of Academic Libraries

Science.gov (United States)

Oberlander, Cyril

2012-01-01

A mission-critical system is one that is so intertwined with the operation of an organization that the organization can scarcely function without it. Just as in corporations, mission-critical library systems offer the capability to unlock talent and time. They are essential to the transformation of higher education and the learning environment. A…

Solar Electric and Chemical Propulsion Technology Applications to a Titan Orbiter/Lander Mission

Science.gov (United States)

Cupples, Michael

2007-01-01

Several advanced propulsion technology options were assessed for a conceptual Titan Orbiter/Lander mission. For convenience of presentation, the mission was broken into two phases: interplanetary and Titan capture. The interplanetary phase of the mission was evaluated for an advanced Solar Electric Propulsion System (SEPS), while the Titan capture phase was evaluated for state-of-art chemical propulsion (NTO/Hydrazine), three advanced chemical propulsion options (LOX/Hydrazine, Fluorine/Hydrazine, high Isp mono-propellant), and advanced tank technologies. Hence, this study was referred to as a SEPS/Chemical based option. The SEPS/Chemical study results were briefly compared to a 2002 NASA study that included two general propulsion options for the same conceptual mission: an all propulsive based mission and a SEPS/Aerocapture based mission. The SEP/Chemical study assumed identical science payload as the 2002 NASA study science payload. The SEPS/Chemical study results indicated that the Titan mission was feasible for a medium launch vehicle, an interplanetary transfer time of approximately 8 years, an advanced SEPS (30 kW), and current chemical engine technology (yet with advanced tanks) for the Titan capture. The 2002 NASA study showed the feasibility of the mission based on a somewhat smaller medium launch vehicle, an interplanetary transfer time of approximately 5.9 years, an advanced SEPS (24 kW), and advanced Aerocapture based propulsion technology for the Titan capture. Further comparisons and study results were presented for the advanced chemical and advanced tank technologies.

Estimation of functional failure probability of passive systems based on subset simulation method

International Nuclear Information System (INIS)

Wang Dongqing; Wang Baosheng; Zhang Jianmin; Jiang Jing

2012-01-01

In order to solve the problem of multi-dimensional epistemic uncertainties and small functional failure probability of passive systems, an innovative reliability analysis algorithm called subset simulation based on Markov chain Monte Carlo was presented. The method is found on the idea that a small failure probability can be expressed as a product of larger conditional failure probabilities by introducing a proper choice of intermediate failure events. Markov chain Monte Carlo simulation was implemented to efficiently generate conditional samples for estimating the conditional failure probabilities. Taking the AP1000 passive residual heat removal system, for example, the uncertainties related to the model of a passive system and the numerical values of its input parameters were considered in this paper. And then the probability of functional failure was estimated with subset simulation method. The numerical results demonstrate that subset simulation method has the high computing efficiency and excellent computing accuracy compared with traditional probability analysis methods. (authors)

Planned Products of the Mars Structure Service for the InSight Mission to Mars

Science.gov (United States)

Panning, Mark P.; Lognonné, Philippe; Bruce Banerdt, W.; Garcia, Raphaël; Golombek, Matthew; Kedar, Sharon; Knapmeyer-Endrun, Brigitte; Mocquet, Antoine; Teanby, Nick A.; Tromp, Jeroen; Weber, Renee; Beucler, Eric; Blanchette-Guertin, Jean-Francois; Bozdağ, Ebru; Drilleau, Mélanie; Gudkova, Tamara; Hempel, Stefanie; Khan, Amir; Lekić, Vedran; Murdoch, Naomi; Plesa, Ana-Catalina; Rivoldini, Atillio; Schmerr, Nicholas; Ruan, Youyi; Verhoeven, Olivier; Gao, Chao; Christensen, Ulrich; Clinton, John; Dehant, Veronique; Giardini, Domenico; Mimoun, David; Thomas Pike, W.; Smrekar, Sue; Wieczorek, Mark; Knapmeyer, Martin; Wookey, James

2017-10-01

The InSight lander will deliver geophysical instruments to Mars in 2018, including seismometers installed directly on the surface (Seismic Experiment for Interior Structure, SEIS). Routine operations will be split into two services, the Mars Structure Service (MSS) and Marsquake Service (MQS), which will be responsible, respectively, for defining the structure models and seismicity catalogs from the mission. The MSS will deliver a series of products before the landing, during the operations, and finally to the Planetary Data System (PDS) archive. Prior to the mission, we assembled a suite of a priori models of Mars, based on estimates of bulk composition and thermal profiles. Initial models during the mission will rely on modeling surface waves and impact-generated body waves independent of prior knowledge of structure. Later modeling will include simultaneous inversion of seismic observations for source and structural parameters. We use Bayesian inversion techniques to obtain robust probability distribution functions of interior structure parameters. Shallow structure will be characterized using the hammering of the heatflow probe mole, as well as measurements of surface wave ellipticity. Crustal scale structure will be constrained by measurements of receiver function and broadband Rayleigh wave ellipticity measurements. Core interacting body wave phases should be observable above modeled martian noise levels, allowing us to constrain deep structure. Normal modes of Mars should also be observable and can be used to estimate the globally averaged 1D structure, while combination with results from the InSight radio science mission and orbital observations will allow for constraint of deeper structure.

AUTONOMOUS UNMANNED HELICOPTER SYSTEM FOR REMOTE SENSING MISSIONS IN UNKNOWN ENVIRONMENTS

Directory of Open Access Journals (Sweden)

T. Merz

2012-09-01

Full Text Available This paper presents the design of an autonomous unmanned helicopter system for low-altitude remote sensing. The proposed concepts and methods are generic and not limited to a specific helicopter. The development was driven by the need for a dependable, modular, and affordable system with sufficient payload capacity suitable for both research and real-world deployment. The helicopter can be safely operated without a backup pilot in a contained area beyond visual range. This enables data collection in inaccessible or dangerous areas. Thanks to its terrain following and obstacle avoidance capability, the system does not require a priori information about terrain elevation and obstacles. Missions are specified in state diagrams and flight plans. We present performance characteristics of our system and show results of its deployment in real-world scenarios. We have successfully completed several dozen infrastructure inspection missions and crop monitoring missions facilitating plant phenomics studies.

Tracking and data system support for the Mariner Mars 1971 mission. Volume 3: Orbit insertion through end of primary mission

Science.gov (United States)

Barnum, P. W.; Renzetti, N. A.; Textor, G. P.; Kelly, L. B.

1973-01-01

The Tracking and Data System (TDS) Support for the Mariner Mars 1971 Mission final report contains the deep space tracking and data acquisition activities in support of orbital operations. During this period a major NASA objective was accomplished: completion of the 180th revolution and 90th day of data gathering with the spacecraft about the planet Mars. Included are presentations of the TDS flight support pass chronology data for each of the Deep Space Stations used, and performance evaluation for the Deep Space Network Telemetry, Tracking, Command, and Monitor Systems. With the loss of Mariner 8 at launch, Mariner 9 assumed the mission plan of Mariner 8, which included the TV mapping cycles and a 12-hr orbital period. The mission plan was modified as a result of a severe dust storm on the surface of Mars, which delayed the start of the TV mapping cycles. Thus, the end of primary mission date was extended to complete the TV mapping cycles.

Deep Space Cryocooler System (DSCS), Phase I

Data.gov (United States)

National Aeronautics and Space Administration — As NASA missions continue to extend the horizon beyond near-Earth missions, higher performance systems must evolve to address the challenges of reduced power...

Phase diagrams of Pr-C system

International Nuclear Information System (INIS)

Eremenko, V.N.; Velikanova, T.Ya.; Gordijchuk, O.V.

1988-01-01

Results of the X-ray phase, metallographic and high-temperature differential thermal analysis are used for the first time to plot a diagram of the Pr-C system state. Carbides are formed in the system: Pr 2 C 3 with the bcc-structure of the Pu 2 C 3 type and with the period a 0 = 0.85722+-0.00026 within the phase region + 2 C 3 >, a 0 0.86078+-0.00016 nm - within the region 2 C 3 >+α-PrC 2 ; dimorphous PrC 2 : α-PrC 2 with the bct-structure of the CaC 2 type and periods a 0.38517+-0.00011, c 0 = 0.64337+-0.00019 nm; β-PrC 2 with the fcc-structure, probably, of KCN type. Dicarbide melts congruently at 2320 grad. C, forming eutectics with graphite at 2254+-6 grad. C and composition of 71.5% (at.)C. It is polymorphously transformed in the phase region 2 C 3 > + 2 > at 1145+-4 grad. C, and in the region 2 >+C at 1134+-4 grad. C. Sesquicarbide melts incongruently at 1545+-4 grad. C. The eutectic reaction L ↔ + 2 C 3 > occurs at 800+-4 grad. C, the eutectic composition ∼ 15% (at.)C. The temperature of the eutectoid reaction ↔ + 2 C 3 > is 675+-6 grad C. The limiting carbon solubility in β-Pr is about 8 and in α-Pr it is about 5% (at.)

The Earth Observing System Terra Mission

Science.gov (United States)

Kaufman, Yoram J.; Einaudi, Franco (Technical Monitor)

2000-01-01

Langley's remarkable solar and lunar spectra collected from Mt. Whitney inspired Arrhenius to develop the first quantitative climate model in 1896. After the launch in Dec. 16 1999, NASA's Earth Observing AM Satellite (EOS-Terra) will repeat Langley's experiment, but for the entire planet, thus pioneering a wide array of calibrated spectral observations from space of the Earth System. Conceived in response to real environmental problems, EOS-Terra, in conjunction with other international satellite efforts, will fill a major gap in current efforts by providing quantitative global data sets with a resolution better than 1 km on the physical, chemical and biological elements of the earth system. Thus, like Langley's data, EOS-Terra can revolutionize climate research by inspiring a new generation of climate system models and enable us to assess the human impact on the environment. In the talk I shall review the historical perspective of the Terra mission and the key new elements of the mission. We expect to have first images that demonstrate the most innovative capability from EOS Terra 5 instruments: MODIS - 1.37 micron cirrus cloud channel; 250m daily coverage for clouds and vegetation change; 7 solar channels for land and aerosol studies; new fire channels; Chlorophyll fluorescence; MISR - first 9 multi angle views of clouds and vegetation; MOPITT - first global CO maps and C114 maps; ASTER - Thermal channels for geological studies with 15-90 m resolution.

Trajectory design for a lunar mapping and near-Earth-asteroid flyby mission

Science.gov (United States)

Dunham, David W.; Farquhar, Robert W.

1993-01-01

In August, 1994, the unusual asteroid (1620) Geographos will pass very close to the Earth. This provides one of the best opportunities for a low-cost asteroid flyby mission that can be achieved with the help of a gravity assist from the Moon during the years 1994 and 1995. A Geographos flyby mission, including a lunar orbiting phase, was recommended to the Startegic Defense Initiative (SDI) Office when they were searching for ideas for a deep-space mission to test small imaging systems and other lightweight technologies. The goals for this mission, called Clementine, were defined to consist of a comprehensive lunar mapping phase before leaving the Earth-Moon system to encounter Geographos. This paper describes how the authors calculated a trajectory that met the mission goals within a reasonable total Delta-V budget. The paper also describes some refinements of the initially computed trajectory and alternative trajectories were investigated. The paper concludes with a list of trajectories to fly by other near-Earth asteroids during the two years following the Geographos opportunity. Some of these could be used if the Geographos schedule can not be met. If the 140 deg phase angle of the Geographos encounter turns out to be too risky, a flyby of (2120) Tantalus in January, 1995, has a much more favorable approach illumination. Tantalus apparently can be reached from the same lunar orbit needed to get to Geographos. However, both the flyby speed and distance from the Earth are much larger for Tantalus than for Geographos.

Astrionic system optimization and modular astrionics for NASA missions after 1974. Preliminary definition of astrionic system for space tug Mission Vehicle Payload (MVP)

Science.gov (United States)

1970-01-01

Results of preliminary studies to define the space tug astrionic system, subsystems, and components to meet requirements for a variety of missions are reported. Emphasis is placed on demonstration of the modular astrionics approach in the design of the space tug astrionic system.

Conceptual definition of a technology development mission for advanced solar dynamic power systems

Science.gov (United States)

Migra, R. P.

1986-01-01

An initial conceptual definition of a technology development mission for advanced solar dynamic power systems is provided, utilizing a space station to provide a dedicated test facility. The advanced power systems considered included Brayton, Stirling, and liquid metal Rankine systems operating in the temperature range of 1040 to 1400 K. The critical technologies for advanced systems were identified by reviewing the current state of the art of solar dynamic power systems. The experimental requirements were determined by planning a system test of a 20 kWe solar dynamic power system on the space station test facility. These requirements were documented via the Mission Requirements Working Group (MRWG) and Technology Development Advocacy Group (TDAG) forms. Various concepts or considerations of advanced concepts are discussed. A preliminary evolutionary plan for this technology development mission was prepared.

75 FR 5146 - Hewlett Packard Company Business Critical Systems, Mission Critical Business Software Division...

Science.gov (United States)

2010-02-01

... Packard Company Business Critical Systems, Mission Critical Business Software Division, OpenVMS Operating... Colorado, Marlborough, MA; Hewlett Packard Company Business Critical Systems, Mission Critical Business... Assistance on August 27, 2009, applicable to workers of Hewlett Packard Company, Business Critical Systems...

Using NASA's Space Launch System to Enable Game Changing Science Mission Designs

Science.gov (United States)

Creech, Stephen D.

2013-01-01

NASA's Marshall Space Flight Center is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will help restore U.S. leadership in space by carrying the Orion Multi-Purpose Crew Vehicle and other important payloads far beyond Earth orbit. Its evolvable architecture will allow NASA to begin with Moon fly-bys and then go on to transport humans or robots to distant places such as asteroids, Mars, and the outer solar system. Designed to simplify spacecraft complexity, the SLS rocket will provide improved mass margins and radiation mitigation, and reduced mission durations. These capabilities offer attractive advantages for ambitious missions such as a Mars sample return, by reducing infrastructure requirements, cost, and schedule. For example, if an evolved expendable launch vehicle (EELV) were used for a proposed mission to investigate the Saturn system, a complicated trajectory would be required with several gravity-assist planetary fly-bys to achieve the necessary outbound velocity. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip times and cost. As this paper will report, the SLS rocket will launch payloads of unprecedented mass and volume, such as monolithic telescopes and in-space infrastructure. Thanks to its ability to co-manifest large payloads, it also can accomplish complex missions in fewer launches. Future analyses will include reviews of alternate mission concepts and detailed evaluations of SLS figures of merit, helping the new rocket revolutionize science mission planning and design for years to come.

A legacy endures. A Maine system emphasizes its sponsor's mission in all aspects of its work.

Science.gov (United States)

Stapleton, Marguerite

2005-01-01

The Sisters of Charity Health System, Lewiston, ME, a member of Covenant Health Systems, Lexington, MA, remains deeply committed to the mission of service begun by its foundress, St. Marguerite d'Youville. Although St. Marguerite experienced a hard life, her resilience and her commitment to the poor and disadvantaged serve as an inspiration to those who continue her legacy of compassionate care. The founding work of St. Marguerite and the sisters has helped to foster a culture in which the mission of service thrives among the system's 2,000 employees. This culture can be attributed to two things: the system's organizational values of compassion, stewardship, respect, and excellence; and the recognition of those employees whose work embodies these values. From the boardroom to the patient room, mission is integrated into each decision and action. Every two years, each of Covenant Health System's member facilities engages in a mission assessment process that examines various aspects of mission, including Catholic identity, holistic care, care for the poor, mission values integration, ethics and employee relations. In addition, the Sisters of Charity Health System's board has its own standing Mission and Community Committee, which looks strategically at how creatively and faithfully the system is continuing to live its mission.

Earth Observing System (EOS) Aqua Launch and Early Mission Attitude Support Experiences

Science.gov (United States)

Tracewell, D.; Glickman, J.; Hashmall, J.; Natanson, G.; Sedlak, J.

2003-01-01

The Earth Observing System (EOS) Aqua satellite was successfully launched on May 4,2002. Aqua is the second in the series of EOS satellites. EOS is part of NASA s Earth Science Enterprise Program, whose goals are to advance the scientific understanding of the Earth system. Aqua is a three-axis stabilized, Earth-pointing spacecraft in a nearly circular, sun-synchronous orbit at an altitude of 705 km. The Goddard Space Flight Center (GSFC) Flight Dynamics attitude team supported all phases of the launch and early mission. This paper presents the main results and lessons learned during this period, including: real-time attitude mode transition support, sensor calibration, onboard computer attitude validation, response to spacecraft emergencies, postlaunch attitude analyses, and anomaly resolution. In particular, Flight Dynamics support proved to be invaluable for successful Earth acquisition, fine-point mode transition, and recognition and correction of several anomalies, including support for the resolution of problems observed with the MODIS instrument.

Tank waste remediation system retrieval and disposal mission infrastructure plan

International Nuclear Information System (INIS)

Root, R.W.

1998-01-01

This system plan presents the objectives, organization, and management and technical approaches for the Infrastructure Program. This Infrastructure Plan focuses on the Tank Waste Remediation System (TWRS) Project's Retrieval and Disposal Mission

Short rendezvous missions for advanced Russian human spacecraft

Science.gov (United States)

Murtazin, Rafail F.; Budylov, Sergey G.

2010-10-01

The two-day stay of crew in a limited inhabited volume of the Soyuz-TMA spacecraft till docking to ISS is one of the most stressful parts of space flight. In this paper a number of possible ways to reduce the duration of the free flight phase are considered. The duration is defined by phasing strategy that is necessary for reduction of the phase angle between the chaser and target spacecraft. Some short phasing strategies could be developed. The use of such strategies creates more comfortable flight conditions for crew thanks to short duration and additionally it allows saving spacecraft's life support resources. The transition from the methods of direct spacecraft rendezvous using one orbit phasing (first flights of " Vostok" and " Soyuz" vehicles) to the currently used methods of two-day rendezvous mission can be observed in the history of Soviet manned space program. For an advanced Russian human rated spacecraft the short phasing strategy is recommended, which can be considered as a combination between the direct and two-day rendezvous missions. The following state of the art technologies are assumed available: onboard accurate navigation; onboard computations of phasing maneuvers; launch vehicle with high accuracy injection orbit, etc. Some operational requirements and constraints for the strategies are briefly discussed. In order to provide acceptable phase angles for possible launch dates the experience of the ISS altitude profile control can be used. As examples of the short phasing strategies, the following rendezvous missions are considered: direct ascent, short mission with the phasing during 3-7 orbits depending on the launch date (nominal or backup). For each option statistical modeling of the rendezvous mission is fulfilled, as well as an admissible phase angle range, accuracy of target state vector and addition fuel consumption coming out of emergency is defined. In this paper an estimation of pros and cons of all options is conducted.

Integrated dynamic modeling and management system mission analysis

Energy Technology Data Exchange (ETDEWEB)

Lee, A.K.

1994-12-28

This document summarizes the mission analysis performed on the Integrated Dynamic Modeling and Management System (IDMMS). The IDMMS will be developed to provide the modeling and analysis capability required to understand the TWRS system behavior in terms of the identified TWRS performance measures. The IDMMS will be used to demonstrate in a verified and validated manner the satisfactory performance of the TWRS system configuration and assurance that the requirements have been satisfied.

Integrated dynamic modeling and management system mission analysis

International Nuclear Information System (INIS)

Lee, A.K.

1994-01-01

This document summarizes the mission analysis performed on the Integrated Dynamic Modeling and Management System (IDMMS). The IDMMS will be developed to provide the modeling and analysis capability required to understand the TWRS system behavior in terms of the identified TWRS performance measures. The IDMMS will be used to demonstrate in a verified and validated manner the satisfactory performance of the TWRS system configuration and assurance that the requirements have been satisfied

Precise Propagation of Upper and Lower Probability Bounds in System P

OpenAIRE

Gilio, Angelo

2000-01-01

In this paper we consider the inference rules of System P in the framework of coherent imprecise probabilistic assessments. Exploiting our algorithms, we propagate the lower and upper probability bounds associated with the conditional assertions of a given knowledge base, automatically obtaining the precise probability bounds for the derived conclusions of the inference rules. This allows a more flexible and realistic use of System P in default reasoning and provides an exact illustration of ...

Risk Assessment of Bone Fracture During Space Exploration Missions to the Moon and Mars

Science.gov (United States)

Lewandowski, Beth E.; Myers, Jerry G.; Nelson, Emily S.; Griffin, Devon

2008-01-01

The possibility of a traumatic bone fracture in space is a concern due to the observed decrease in astronaut bone mineral density (BMD) during spaceflight and because of the physical demands of the mission. The Bone Fracture Risk Module (BFxRM) was developed to quantify the probability of fracture at the femoral neck and lumbar spine during space exploration missions. The BFxRM is scenario-based, providing predictions for specific activities or events during a particular space mission. The key elements of the BFxRM are the mission parameters, the biomechanical loading models, the bone loss and fracture models and the incidence rate of the activity or event. Uncertainties in the model parameters arise due to variations within the population and unknowns associated with the effects of the space environment. Consequently, parameter distributions were used in Monte Carlo simulations to obtain an estimate of fracture probability under real mission scenarios. The model predicts an increase in the probability of fracture as the mission length increases and fracture is more likely in the higher gravitational field of Mars than on the moon. The resulting probability predictions and sensitivity analyses of the BFxRM can be used as an engineering tool for mission operation and resource planning in order to mitigate the risk of bone fracture in space.

Recommendation of a More Effective Alternative to the NASA Launch Services Program Mission Integration Reporting System (MIRS) and Implementation of Updates to the Mission Plan

Science.gov (United States)

Dunn, Michael R.

2014-01-01

Over the course of my internship in the Flight Projects Office of NASA's Launch Services Program (LSP), I worked on two major projects, both of which dealt with updating current systems to make them more accurate and to allow them to operate more efficiently. The first project dealt with the Mission Integration Reporting System (MIRS), a web-accessible database application used to manage and provide mission status reporting for the LSP portfolio of awarded missions. MIRS had not gone through any major updates since its implementation in 2005, and it was my job to formulate a recommendation for the improvement of the system. The second project I worked on dealt with the Mission Plan, a document that contains an overview of the general life cycle that is followed by every LSP mission. My job on this project was to update the information currently in the mission plan and to add certain features in order to increase the accuracy and thoroughness of the document. The outcomes of these projects have implications in the orderly and efficient operation of the Flight Projects Office, and the process of Mission Management in the Launch Services Program as a whole.

Scaling Qualitative Probability

OpenAIRE

Burgin, Mark

2017-01-01

There are different approaches to qualitative probability, which includes subjective probability. We developed a representation of qualitative probability based on relational systems, which allows modeling uncertainty by probability structures and is more coherent than existing approaches. This setting makes it possible proving that any comparative probability is induced by some probability structure (Theorem 2.1), that classical probability is a probability structure (Theorem 2.2) and that i...

Real-Time Analytics Test System for Distributed Spacecraft Missions

Data.gov (United States)

National Aeronautics and Space Administration — Upcoming DSM missions will produce unprecedented amounts of data during both I&T and flight, overwhelming current command/telemetry systems. The amount of data,...

GPS Navigation Above 76,000 km for the MMS Mission

Science.gov (United States)

Winternitz, Luke; Bamford, Bill; Price, Samuel; Long, Anne; Farahmand, Mitra; Carpenter, Russell

2016-01-01

NASA's MMS mission, launched in March of 2015,consists of a controlled formation of four spin-stabilized spacecraft in similar highly elliptic orbits reaching apogee at radial distances of 12and 25 Earth radii in the first and second phases of the mission. Navigation for MMS is achieved independently onboard each spacecraft by processing GPS observables using NASA GSFC's Navigator GPS receiver and the Goddard Enhanced Onboard Navigation System (GEONS) extended Kalman filter software. To our knowledge, MMS constitutes, by far, the highest-altitude operational use of GPS to date and represents the culmination of over a decade of high-altitude GPS navigation research and development at NASA GSFC. In this paper we will briefly describe past and ongoing high-altitude GPS research efforts at NASA GSFC and elsewhere, provide details on the design of the MMS GPS navigation system, and present on-orbit performance data. We extrapolate these results to predict performance in the Phase 2b mission orbit, and conclude with a discussion of the implications of the MMS results for future high-altitude GPS navigation, which we believe to be broad and far-reaching.

Swarm: ESA's Magnetic Field Mission

Science.gov (United States)

Plank, G.; Floberghagen, R.; Menard, Y.; Haagmans, R.

2013-12-01

Swarm is the fifth Earth Explorer mission in ESA's Living Planet Programme, and is scheduled for launch in fall 2013. The objective of the Swarm mission is to provide the best-ever survey of the geomagnetic field and its temporal evolution using a constellation of three identical satellites. The mission shall deliver data that allow access to new insights into the Earth system by improved scientific understanding of the Earth's interior and near-Earth electromagnetic environment. After launch and triple satellite release at an initial altitude of about 490 km, a pair of the satellites will fly side-by-side with slowly decaying altitude, while the third satellite will be lifted to 530 km to complete the Swarm constellation. High-precision and high-resolution measurements of the strength, direction and variation of the magnetic field, complemented by precise navigation, accelerometer and electric field measurements, will provide the observations required to separate and model various sources of the geomagnetic field and near-Earth current systems. The mission science goals are to provide a unique view into Earth's core dynamics, mantle conductivity, crustal magnetisation, ionospheric and magnetospheric current systems and upper atmosphere dynamics - ranging from understanding the geodynamo to contributing to space weather. The scientific objectives and results from recent scientific studies will be presented. In addition the current status of the project, which is presently in the final stage of the development phase, will be addressed. A consortium of European scientific institutes is developing a distributed processing system to produce geophysical (Level 2) data products for the Swarm user community. The setup of the Swarm ground segment and the contents of the data products will be addressed. In case the Swarm satellites are already in orbit, a summary of the on-going mission operations activities will be given. More information on Swarm can be found at www.esa.int/esaLP/LPswarm.html.

SPICE for ESA Planetary Missions: geometry and visualization support to studies, operations and data analysis within your reach

Science.gov (United States)

Costa, Marc

2018-05-01

JUICE is a mission chosen in the framework of the Cosmic Vision 2015-2024 program of the SRE. JUICE will survey the Jovian system with a special focus on the three Galilean Moons. Currently the mission is under study activities during its Definition Phase. For this period the future mission scenarios are being studied by the Science Working Team (SWT). The Mission Analysis and Payload Support (MAPPS) and the Solar System Science Operations Laboratory (SOLab) tools are being used to provide active support to the SWT in synergy with other operational tools used in the Department in order to evaluate the feasibility of those scenarios. This contribution will outline the capabilities, synergies as well as use cases of the mentioned tools focusing on the support provided to JUICEís study phase on the study of its critical operational scenarios and the early developments of its Science Ground Segment demonstrating the added value that such a tool provides to planetary science missions.

Designing astrophysics missions for NASA's Space Launch System

Science.gov (United States)

Stahl, H. Philip; Hopkins, Randall C.; Schnell, Andrew; Smith, David Alan; Jackman, Angela; Warfield, Keith R.

2016-10-01

Large space telescope missions have always been limited by their launch vehicle's mass and volume capacities. The Hubble Space Telescope was specifically designed to fit inside the Space Shuttle and the James Webb Space Telescope was specifically designed to fit inside an Ariane 5. Astrophysicists desire even larger space telescopes. NASA's "Enduring Quests Daring Visions" report calls for an 8- to 16-m Large UV-Optical-IR (LUVOIR) Surveyor mission to enable ultrahigh-contrast spectroscopy and coronagraphy. Association of Universities for Research in Astronomy's "From Cosmic Birth to Living Earth" report calls for a 12-m class High-Definition Space Telescope to pursue transformational scientific discoveries. NASA's "Planning for the 2020 Decadal Survey" calls for a Habitable Exoplanet Imaging (HabEx) and an LUVOIR as well as Far-IR and an X-ray Surveyor missions. Packaging larger space telescopes into existing launch vehicles is a significant engineering complexity challenge that drives cost and risk. NASA's planned Space Launch System (SLS), with its 8- or 10-m diameter fairings and ability to deliver 35 to 45 mt of payload to Sun-Earth-Lagrange-2, mitigates this challenge by fundamentally changing the design paradigm for large space telescopes. This paper introduces the mass and volume capacities of the planned SLS, provides a simple mass allocation recipe for designing large space telescope missions to this capacity, and gives three specific mission concept implementation examples: a 4-m monolithic off-axis telescope, an 8-m monolithic on-axis telescope, and a 12-m segmented on-axis telescope.

Overcoming the Challenges of Implementing a Multi-Mission Distributed Workflow System

Science.gov (United States)

Sayfi, Elias; Cheng, Cecilia; Lee, Hyun; Patel, Rajesh; Takagi, Atsuya; Yu, Dan

2009-01-01

A multi-mission approach to solving the same problems for various projects is enticing. However, the multi-mission approach leads to the need to develop a configurable, adaptable and distributed system to meet unique project requirements. That, in turn, leads to a set of challenges varying from handling synchronization issues to coming up with a smart design that allows the "unknowns" to be decided later. This paper discusses the challenges that the Multi-mission Automated Task Invocation Subsystem (MATIS) team has come up against while designing the distributed workflow system, as well as elaborates on the solutions that were implemented. The first is to design an easily adaptable system that requires no code changes as a result of configuration changes. The number of formal deliveries is often limited because each delivery costs time and money. Changes such as the sequence of programs being called, a change of a parameter value in the program that is being automated should not result in code changes or redelivery.

Virtualization - A Key Cost Saver in NASA Multi-Mission Ground System Architecture

Science.gov (United States)

Swenson, Paul; Kreisler, Stephen; Sager, Jennifer A.; Smith, Dan

2014-01-01

With science team budgets being slashed, and a lack of adequate facilities for science payload teams to operate their instruments, there is a strong need for innovative new ground systems that are able to provide necessary levels of capability processing power, system availability and redundancy while maintaining a small footprint in terms of physical space, power utilization and cooling.The ground system architecture being presented is based off of heritage from several other projects currently in development or operations at Goddard, but was designed and built specifically to meet the needs of the Science and Planetary Operations Control Center (SPOCC) as a low-cost payload command, control, planning and analysis operations center. However, this SPOCC architecture was designed to be generic enough to be re-used partially or in whole by other labs and missions (since its inception that has already happened in several cases!)The SPOCC architecture leverages a highly available VMware-based virtualization cluster with shared SAS Direct-Attached Storage (DAS) to provide an extremely high-performing, low-power-utilization and small-footprint compute environment that provides Virtual Machine resources shared among the various tenant missions in the SPOCC. The storage is also expandable, allowing future missions to chain up to 7 additional 2U chassis of storage at an extremely competitive cost if they require additional archive or virtual machine storage space.The software architecture provides a fully-redundant GMSEC-based message bus architecture based on the ActiveMQ middleware to track all health and safety status within the SPOCC ground system. All virtual machines utilize the GMSEC system agents to report system host health over the GMSEC bus, and spacecraft payload health is monitored using the Hammers Integrated Test and Operations System (ITOS) Galaxy Telemetry and Command (TC) system, which performs near-real-time limit checking and data processing on the

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Republic of Burundi. Draft

International Nuclear Information System (INIS)

Gehrisch, W.; Chaigne, M.

1983-06-01

The basic objective of the International Uranium Resources Evaluation project lUREP is to 'Review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for the discovery of additional uranium resources and to suggest new exploration efforts which might be carried out in promising areas in collaboration with the countries concerned'. Therefore, the scope of the IUREP orientation phase Mission to Burundi was to review all data on past exploration in Burundi, to develop a better understanding of the uranium potential of the country, to make an estimate of the speculative resources of the country, to make recommendation as appropriate on the best methods or techniques for evaluating the resources in the favourable areas and for estimating possible costs as well, to compile a report which could be immediately available to the Burundian authorities. This mission gives a general introduction, a geological review of Burundi, information on non-uranium mining in Burundi, the history of uranium exploration, occurrences of uranium IUREP mission field reconnaissance, favourable areas for speculative potential, the uranium resources position and recommendations for future exploration. Conclusions are the following. The IUREP Orientation -phase mission to Burundi believes that the Speculative Resources of that country fall b etween 300 and 4100 tons uranium oxide but a less speculative appraisal is more likely between 0 and 1000 tons. There has been no uranium production and no official estimates of Uranium Resources in Burundi. Past exploration mainly dating from 1969 onwards and led the UNDP Mineral project has indicated a limited number of uranium occurrences and anomalies. The speculative uranium resources are thought to be possibly associated with potential unconformity related vein-like deposits of the Lower Burundian. Other speculative uranium resources could be associated with granitic or peribatholitic

Time dependent non-extinction probability for prompt critical systems

International Nuclear Information System (INIS)

Gregson, M. W.; Prinja, A. K.

2009-01-01

The time dependent non-extinction probability equation is presented for slab geometry. Numerical solutions are provided for a nested inner/outer iteration routine where the fission terms (both linear and non-linear) are updated and then held fixed over the inner scattering iteration. Time dependent results are presented highlighting the importance of the injection position and angle. The iteration behavior is also described as the steady state probability of initiation is approached for both small and large time steps. Theoretical analysis of the nested iteration scheme is shown and highlights poor numerical convergence for marginally prompt critical systems. An acceleration scheme for the outer iterations is presented to improve convergence of such systems. Theoretical analysis of the acceleration scheme is also provided and the associated decrease in computational run time addressed. (authors)

The correlation of defect distribution in collisional phase with measured cascade collapse probability

International Nuclear Information System (INIS)

Morishita, K.; Ishino, S.; Sekimura, N.

1995-01-01

The spatial distributions of atomic displacement at the end of the collisional phase of cascade damage processes were calculated using the computer simulation code MARLOWE, which is based on the binary collision approximation (BCA). The densities of the atomic displacement were evaluated in high dense regions (HDRs) of cascades in several pure metals (Fe, Ni, Cu, Ag, Au, Mo and W). They were compared with the measured cascade collapse probabilities reported in the literature where TEM observations were carried out using thin metal foils irradiated by low-dose ions at room temperature. We found that there exists the minimum or ''critical'' values of the atomic displacement densities for the HDR to collapse into TEM-visible vacancy clusters. The critical densities are generally independent of the cascade energy in the same metal. Furthermore, the material dependence of the critical densities can be explained by the difference in the vacancy mobility at the melting temperature of target materials. This critical density calibration, which is extracted from the ion-irradiation experiments and the BCA simulations, is applied to estimation of cascade collapse probabilities in the metals irradiated by fusion neutrons. (orig.)

Innovative Applications of DoD Propulsion Technology for Low-Cost Satellite Missions, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — We are proposing to leverage the Missile Defense Agency investments in high-performance propulsion systems for low-cost space missions with large Dv requirements,...

(abstract) Science-Project Interaction in the Low-Cost Mission

Science.gov (United States)

Wall, Stephen D.

1994-01-01

Large, complex, and highly optimized missions have performed most of the preliminary reconnaisance of the solar system. As a result we have now mapped significant fractions of its total surface (or surface-equivalent) area. Now, however, scientific exploration of the solar system is undergoing a major change in scale, and existing missions find it necessary to limit costs while fulfilling existing goals. In the future, NASA's Discovery program will continue the reconnaisance, exploration, and diagnostic phases of planetary research using lower cost missions, which will include lower cost mission operations systems (MOS). Historically, one of the more expensive functions of MOS has been its interaction with the science community. Traditional MOS elements that this interaction have embraced include mission planning, science (and engineering) event conflict resolution, sequence optimization and integration, data production (e.g., assembly, enhancement, quality assurance, documentation, archive), and other science support services. In the past, the payoff from these efforts has been that use of mission resources has been highly optimized, constraining resources have been generally completely consumed, and data products have been accurate and well documented. But because these functions are expensive we are now challenged to reduce their cost while preserving the benefits. In this paper, we will consider ways of revising the traditional MOS approach that might save project resources while retaining a high degree of service to the Projects' customers. Pre-launch, science interaction can be made simplier by limiting numbers of instruments and by providing greater redundancy in mission plans. Post launch, possibilities include prioritizing data collection into a few categories, easing requirements on real-time of quick-look data delivery, and closer integration of scientists into the mission operation.

The missions and means framework as an ontology

Science.gov (United States)

Deitz, Paul H.; Bray, Britt E.; Michaelis, James R.

2016-05-01

The analysis of warfare frequently suffers from an absence of logical structure for a] specifying explicitly the military mission and b] quantitatively evaluating the mission utility of alternative products and services. In 2003, the Missions and Means Framework (MMF) was developed to redress these shortcomings. The MMF supports multiple combatants, levels of war and, in fact, is a formal embodiment of the Military Decision-Making Process (MDMP). A major effect of incomplete analytic discipline in military systems analyses is that they frequently fall into the category of ill-posed problems in which they are under-specified, under-determined, or under-constrained. Critical context is often missing. This is frequently the result of incomplete materiel requirements analyses which have unclear linkages to higher levels of warfare, system-of-systems linkages, tactics, techniques and procedures, and the effect of opposition forces. In many instances the capabilities of materiel are assumed to be immutable. This is a result of not assessing how platform components morph over time due to damage, logistics, or repair. Though ill-posed issues can be found many places in military analysis, probably the greatest challenge comes in the disciplines of C4ISR supported by ontologies in which formal naming and definition of the types, properties, and interrelationships of the entities are fundamental to characterizing mission success. Though the MMF was not conceived as an ontology, over the past decade some workers, particularly in the field of communication, have labelled the MMF as such. This connection will be described and discussed.

Improved Traceability of a Small Satellite Mission Concept to Requirements Using Model Based System Engineering

Science.gov (United States)

Reil, Robin L.

2014-01-01

Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the "traditional" document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This paper presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magic's MagicDraw modeling tool. The model incorporates mission concept and requirement information from the mission's original DBSE design efforts. Active dependency relationships are modeled to demonstrate the completeness and consistency of the requirements to the mission concept. Anecdotal information and process-duration metrics are presented for both the MBSE and original DBSE design efforts of SporeSat.

NASA's Soil Moisture Active and Passive (SMAP) Mission

Science.gov (United States)

Kellogg, Kent; Njoku, Eni; Thurman, Sam; Edelstein, Wendy; Jai, Ben; Spencer, Mike; Chen, Gun-Shing; Entekhabi, Dara; O'Neill, Peggy; Piepmeier, Jeffrey;

Mission needs and system commonality for space nuclear power and propulsion

International Nuclear Information System (INIS)

Buden, D.; Zuppero, A.; Redd, L.

1993-01-01

Nuclear power enables or significantly enhances a variety of space missions whether near-Earth, or for solar system exploration, lunar-Mars exploration and recovery of near-Earth resources. Performance optimizations for individual missions leads to a large number of power and propulsion systems to be developed. However, the realities of the budget and schedules indicates that the number of nuclear systems that will be developed are limited. One needs to seek the ''minimum requirements'' to do a job rather than the last ounce of performance, and areas of commonality. To develop a minimum number of systems to meet the overall DoD, NASA, and commercial needs, the broad spectrum of requirements has been examined along with cost drivers

Effect of power system technology and mission requirements on high altitude long endurance aircraft

Science.gov (United States)

Colozza, Anthony J.

1994-01-01

An analysis was performed to determine how various power system components and mission requirements affect the sizing of a solar powered long endurance aircraft. The aircraft power system consists of photovoltaic cells and a regenerative fuel cell. Various characteristics of these components, such as PV cell type, PV cell mass, PV cell efficiency, fuel cell efficiency, and fuel cell specific mass, were varied to determine what effect they had on the aircraft sizing for a given mission. Mission parameters, such as time of year, flight altitude, flight latitude, and payload mass and power, were also altered to determine how mission constraints affect the aircraft sizing. An aircraft analysis method which determines the aircraft configuration, aspect ratio, wing area, and total mass, for maximum endurance or minimum required power based on the stated power system and mission parameters is presented. The results indicate that, for the power system, the greatest benefit can be gained by increasing the fuel cell specific energy. Mission requirements also substantially affect the aircraft size. By limiting the time of year the aircraft is required to fly at high northern or southern latitudes, a significant reduction in aircraft size or increase in payload capacity can be achieved.

Sequential Probability Ratio Test for Spacecraft Collision Avoidance Maneuver Decisions

Science.gov (United States)

Carpenter, J. Russell; Markley, F. Landis

2013-01-01

A document discusses sequential probability ratio tests that explicitly allow decision-makers to incorporate false alarm and missed detection risks, and are potentially less sensitive to modeling errors than a procedure that relies solely on a probability of collision threshold. Recent work on constrained Kalman filtering has suggested an approach to formulating such a test for collision avoidance maneuver decisions: a filter bank with two norm-inequality-constrained epoch-state extended Kalman filters. One filter models the null hypotheses that the miss distance is inside the combined hard body radius at the predicted time of closest approach, and one filter models the alternative hypothesis. The epoch-state filter developed for this method explicitly accounts for any process noise present in the system. The method appears to work well using a realistic example based on an upcoming, highly elliptical orbit formation flying mission.

The Phase-Induced Amplitude Apodization Coronagraph (PIAAC): Performance for Imaging of Earth-like Exoplanets.

Science.gov (United States)

Martinache, F.; Guyon, O.; Pluzhnik, E.; Ridgway, S.; Galicher, R.

2004-12-01

PIAA is one of the powerful applications of pupil remapping. A set of two aspheric mirrors changes the distribution of light and provides an apodized pupil, suitable for coronagraphy, without light loss on an absorbing mask. Deployed on to a space telescope with coronagraphic quality optics, it may allow planet detection from a 1.2 λ /d inner working distance and a full working field. We describe the performance of a PIAA version of NASA's Terrestrial Planet Finder (TPF) in terms of Signal to Noise Ratio and compare it to Classical Pupil Apodization (CPA) performance. We also discuss the necessity of using different occulting masks and give an estimate of the total exposure time for the planet detection phase of the TPF mission. This study is based on realistic Monte Carlo simulations of terrestrial planets orbiting around F, G, K stars within 30 pc around the solar system and includes planet phase and angular separation probabilities. This work was carried out under JPL contract numbers 1254445 and 1257767 for Development of Technologies for the Terrestrial Planet Finder Mission, with the support and hospitality of the National Astronomical Observatory of Japan.

Analysis of two-phase flow induced vibrations in perpendiculary supported U-type piping systems

International Nuclear Information System (INIS)

Hiramatsu, Tsutomu; Komura, Yoshiaki; Ito, Atsushi.

1984-01-01

The perpose of this analysis is to predict the vibration level of a pipe conveying a two-phase flowing fluid. Experiments were carried out with a perpendiculary supported U-type piping system, conveying an air-water two-phase flow in a steady state condition. Fluctuation signals are observed by a void signal sensor, and power spectral densities and probability density functions are obtained from the void signals. Theoretical studies using FEM and an estimation of the exciting forces from the PSD of void signals, provided a good predictional estimation of vibration responses of the piping system. (author)

Parallel Enhancements of the General Mission Analysis Tool, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The General Mission Analysis Tool (GMAT) is a state of the art spacecraft mission design tool under active development at NASA's Goddard Space Flight Center (GSFC)....

MSFC Skylab electrical power systems mission evaluation

Science.gov (United States)

Woosley, A. P.

1974-01-01

The design, development, and operation of the Skylab electrical power system are discussed. The electrical systems for the airlock module of the orbital workshop and the Apollo telescope mount are described. Skylab is considered an integral laboratory, however, both cluster and module hardware distinct sections are included. Significant concept and requirement evolution, testing, and modifications resulting from tests are briefly summarized to aid in understanding the launch configuration description and the procedures and performance discussed for in-orbit operation. Specific problems encountered during Skylab orbital missions are analyzed.

A Combined Solar Electric and Storable Chemical Propulsion Vehicle for Piloted Mars Missions

Science.gov (United States)

Mercer, Carolyn R.; Oleson, Steven R.; Drake, Bret G.

2014-01-01

The Mars Design Reference Architecture (DRA) 5.0 explored a piloted Mars mission in the 2030 timeframe, focusing on architecture and technology choices. The DRA 5.0 focused on nuclear thermal and cryogenic chemical propulsion system options for the mission. Follow-on work explored both nuclear and solar electric options. One enticing option that was found in a NASA Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) design study used a combination of a 1-MW-class solar electric propulsion (SEP) system combined with storable chemical systems derived from the planned Orion crew vehicle. It was found that by using each propulsion system at the appropriate phase of the mission, the entire SEP stage and habitat could be placed into orbit with just two planned Space Launch System (SLS) heavy lift launch vehicles assuming the crew would meet up at the Earth-Moon (E-M) L2 point on a separate heavy-lift launch. These appropriate phases use high-thrust chemical propulsion only in gravity wells when the vehicle is piloted and solar electric propulsion for every other phase. Thus the SEP system performs the spiral of the unmanned vehicle from low Earth orbit (LEO) to E-M L2 where the vehicle meets up with the multi-purpose crew vehicle. From here SEP is used to place the vehicle on a trajectory to Mars. With SEP providing a large portion of the required capture and departure changes in velocity (delta V) at Mars, the delta V provided by the chemical propulsion is reduced by a factor of five from what would be needed with chemical propulsion alone at Mars. This trajectory also allows the SEP and habitat vehicle to arrive in the highly elliptic 1-sol parking orbit compatible with envisioned Mars landing concepts. This paper explores mission options using between SEP and chemical propulsion, the design of the SEP system including the solar array and electric propulsion systems, and packaging in the SLS shroud. Design trades of stay time, power level

Solar Sail Attitude Control System for the NASA Near Earth Asteroid Scout Mission

Science.gov (United States)

Orphee, Juan; Diedrich, Ben; Stiltner, Brandon; Becker, Chris; Heaton, Andrew

2017-01-01

An Attitude Control System (ACS) has been developed for the NASA Near Earth Asteroid (NEA) Scout mission. The NEA Scout spacecraft is a 6U cubesat with an eighty-six square meter solar sail for primary propulsion that will launch as a secondary payload on the Space Launch System (SLS) Exploration Mission 1 (EM-1) and rendezvous with a target asteroid after a two year journey, and will conduct science imagery. The spacecraft ACS consists of three major actuating subsystems: a Reaction Wheel (RW) control system, a Reaction Control System (RCS), and an Active Mass Translator (AMT) system. The reaction wheels allow fine pointing and higher rates with low mass actuators to meet the science, communication, and trajectory guidance requirements. The Momentum Management System (MMS) keeps the speed of the wheels within their operating margins using a combination of solar torque and the RCS. The AMT is used to adjust the sign and magnitude of the solar torque to manage pitch and yaw momentum. The RCS is used for initial de-tumble, performing a Trajectory Correction Maneuver (TCM), and performing momentum management about the roll axis. The NEA Scout ACS is able to meet all mission requirements including attitude hold, slews, pointing for optical navigation and pointing for science with margin and including flexible body effects. Here we discuss the challenges and solutions of meeting NEA Scout mission requirements for the ACS design, and present a novel implementation of managing the spacecraft Center of Mass (CM) to trim the solar sail disturbance torque. The ACS we have developed has an applicability to a range of potential missions and does so in a much smaller volume than is traditional for deep space missions beyond Earth.

Space Mission Operations Ground Systems Integration Customer Service

Science.gov (United States)

Roth, Karl

2014-01-01

, and cultural differences, to ensure an efficient response to customer issues using a small Customer Service Team (CST) and adaptability, constant communication with customers, technical expertise and knowledge of services, and dedication to customer service. The HOSC Customer Support Team has implemented a variety of processes, and procedures that help to mitigate the potential problems that arise when integrating ground system services for a variety of complex missions and the lessons learned from this experience will lead the future of customer service in the space operations industry.

Digital communication constraints in prior space missions

Science.gov (United States)

Yassine, Nathan K.

2004-01-01

Digital communication is crucial for space endeavors. Jt transmits scientific and command data between earth stations and the spacecraft crew. It facilitates communications between astronauts, and provides live coverage during all phases of the mission. Digital communications provide ground stations and spacecraft crew precise data on the spacecraft position throughout the entire mission. Lessons learned from prior space missions are valuable for our new lunar and Mars missions set by our president s speech. These data will save our agency time and money, and set course our current developing technologies. Limitations on digital communications equipment pertaining mass, volume, data rate, frequency, antenna type and size, modulation, format, and power in the passed space missions are of particular interest. This activity is in support of ongoing communication architectural studies pertaining to robotic and human lunar exploration. The design capabilities and functionalities will depend on the space and power allocated for digital communication equipment. My contribution will be gathering these data, write a report, and present it to Communications Technology Division Staff. Antenna design is very carefully studied for each mission scenario. Currently, Phased array antennas are being developed for the lunar mission. Phased array antennas use little power, and electronically steer a beam instead of DC motors. There are 615 patches in the phased array antenna. These patches have to be modified to have high yield. 50 patches were created for testing. My part is to assist in the characterization of these patch antennas, and determine whether or not certain modifications to quartz micro-strip patch radiators result in a significant yield to warrant proceeding with repairs to the prototype 19 GHz ferroelectric reflect-array antenna. This work requires learning how to calibrate an automatic network, and mounting and testing antennas in coaxial fixtures. The purpose of this

Probability Estimates of Solar Proton Doses During Periods of Low Sunspot Number for Short Duration Missions

Science.gov (United States)

Atwell, William; Tylka, Allan J.; Dietrich, William F.; Rojdev, Kristina; Matzkind, Courtney

2016-01-01

In an earlier paper presented at ICES in 2015, we investigated solar particle event (SPE) radiation exposures (absorbed dose) to small, thinly-shielded spacecraft during a period when the monthly smoothed sunspot number (SSN) was less than 30. Although such months are generally considered "solar-quiet", SPEs observed during these months even include Ground Level Events, the most energetic type of SPE. In this paper, we add to previous study those SPEs that occurred in 1973-2015 when the SSN was greater than 30 but less than 50. Based on the observable energy range of the solar protons, we classify the event as GLEs, sub-GLEs, and sub-sub-GLEs, all of which are potential contributors to the radiation hazard. We use the spectra of these events to construct a probabilistic model of the absorbed dose due to solar protons when SSN < 50 at various confidence levels for various depths of shielding and for various mission durations. We provide plots and tables of solar proton-induced absorbed dose as functions of confidence level, shielding thickness, and mission-duration that will be useful to system designers.

IMPERA: Integrated Mission Planning for Multi-Robot Systems

Directory of Open Access Journals (Sweden)

Daniel Saur

2015-10-01

Full Text Available This paper presents the results of the project IMPERA (Integrated Mission Planning for Distributed Robot Systems. The goal of IMPERA was to realize an extraterrestrial exploration scenario using a heterogeneous multi-robot system. The main challenge was the development of a multi-robot planning and plan execution architecture. The robot team consists of three heterogeneous robots, which have to explore an unknown environment and collect lunar drill samples. The team activities are described using the language ALICA (A Language for Interactive Agents. Furthermore, we use the mission planning system pRoPhEt MAS (Reactive Planning Engine for Multi-Agent Systems to provide an intuitive interface to generate team activities. Therefore, we define the basic skills of our team with ALICA and define the desired goal states by using a logic description. Based on the skills, pRoPhEt MAS creates a valid ALICA plan, which will be executed by the team. The paper describes the basic components for communication, coordinated exploration, perception and object transportation. Finally, we evaluate the planning engine pRoPhEt MAS in the IMPERA scenario. In addition, we present further evaluation of pRoPhEt MAS in more dynamic environments.

The Successful Conclusion of the Deep Space 1 Mission: Important Results without a Flashy Title

Science.gov (United States)

Rayman, Marc D.

2002-01-01

Conceived in 1995, Deep Space 1 (DS1) was the first mission of NASA s New Millennium program. Its purpose was to test high-risk, advanced technologies important for space and Earth science missions. DS1 s payload included ion propulsion, solar concentrator arrays, autonomous navigation and other autonomous systems, miniaturized telecommunications and microelectronic systems, and two highly integrated, compact science instruments. DS1 was launched in October 1998, only 39 months after the initial concept study began, and during its 11-month primary mission it exceeded its requirements. All technologies were rigorously exercised and characterized, thus reducing the cost and risk of subsequent science missions that could consider taking advantage of the capabilities offered by these new systems. Following its primary mission, DS1 embarked on an extended mission devoted to comet science, although it had not been designed for a comet encounter. Less than two months after the beginning of the extended mission, the spacecraft suffered a critical failure with the loss of its star tracker, its only source of 3-axis attitude knowledge. Although this was initially considered to be a catastrophic failure, the project completed an ambitious two-phase, seven-month recovery that included the development of extensive new software and new operations procedures. In September 2001, the spacecraft flawlessly completed a high-risk encounter with comet 19P/Borrelly. Using the two instruments included on the flight for technology tests as well as reprogrammed sensors originally intended for monitoring the effects of the ion propulsion system on the space environment, DS1 returned a rich harvest of data, with panchromatic images, infrared spectra, energy and angle distributions of electron and ion fluxes, ion compositions, and magnetic field and plasma wave measurements. These data constitute the most detailed view of a comet and offer surprising and exciting insights. In addition to the

Preparing and Conducting Review Missions of Instrumentation and Control Systems in Nuclear Power Plants

International Nuclear Information System (INIS)

2011-06-01

The mission for Independent Engineering Review of Instrumentation and Control (I and C) Systems (IERICS) in Nuclear Power Plants (NPPs) has been established with the aim of conducting peer reviews of I and C design documents, implementation processes, prototype I and C systems, and actual systems already deployed in operating NPPs. Organizations in IAEA Member States, such as nuclear utilities, regulators, and technical support organizations can benefit from I and C technical reviews through requesting IERICS missions that provide a detailed technical assessment on I and C systems, as well as recommendations for improvement. The IERICS mission is conducted by a team of international subject matter experts from various complementing technical areas. The review is based on appropriate IAEA documents, such as Safety Guides and Nuclear Energy Series, and the mission's findings are summarized in a mission report, including a list of recommendations, suggestions, and identified good practices. The review is not intended to be a regulatory inspection or an audit against international codes and standards. Rather, it is a peer review aimed at improving design and implementation procedures through an exchange of technical experiences and practices at the working level. The IERICS mission is applicable at any stages of the life cycle of I and C systems in NPPs and it is initiated based on a formal request through official IAEA channels from an organization of a Member State. The formation of the IERICS mission is based on the recommendation of the IAEA Technical Working Group on Nuclear Power Plant Instrumentation and Control (TWG-NPPIC). The recommendation came from the recognition that the IAEA can play an important role in the independent assessment and review of NPP I and C systems in terms of their compliance with IAEA safety guides and technical documents.

Security Vulnerability Profiles of NASA Mission Software: Empirical Analysis of Security Related Bug Reports

Science.gov (United States)

Goseva-Popstojanova, Katerina; Tyo, Jacob P.; Sizemore, Brian

2017-01-01

NASA develops, runs, and maintains software systems for which security is of vital importance. Therefore, it is becoming an imperative to develop secure systems and extend the current software assurance capabilities to cover information assurance and cybersecurity concerns of NASA missions. The results presented in this report are based on the information provided in the issue tracking systems of one ground mission and one flight mission. The extracted data were used to create three datasets: Ground mission IVV issues, Flight mission IVV issues, and Flight mission Developers issues. In each dataset, we identified the software bugs that are security related and classified them in specific security classes. This information was then used to create the security vulnerability profiles (i.e., to determine how, why, where, and when the security vulnerabilities were introduced) and explore the existence of common trends. The main findings of our work include:- Code related security issues dominated both the Ground and Flight mission IVV security issues, with 95 and 92, respectively. Therefore, enforcing secure coding practices and verification and validation focused on coding errors would be cost effective ways to improve mission's security. (Flight mission Developers issues dataset did not contain data in the Issue Category.)- In both the Ground and Flight mission IVV issues datasets, the majority of security issues (i.e., 91 and 85, respectively) were introduced in the Implementation phase. In most cases, the phase in which the issues were found was the same as the phase in which they were introduced. The most security related issues of the Flight mission Developers issues dataset were found during Code Implementation, Build Integration, and Build Verification; the data on the phase in which these issues were introduced were not available for this dataset.- The location of security related issues, as the location of software issues in general, followed the Pareto

Systems engineering functions and requirements for the Hanford cleanup mission. First issue, Addendum 2

Energy Technology Data Exchange (ETDEWEB)

Holmes, J.J.

1994-01-01

This addendum provides the technical detail of a systems engineering functional analysis for the Hanford cleanup mission. Details of the mission analysis including mission statement, scope, problem statement, initial state definition, and final state definition are provided in the parent document. The functional analysis consists of Input Computer Automated Manufacturing Definition (IDEFO) diagrams an definitions, which will be understood by systems engineers, but which may be difficult for others to comprehend. For a more complete explanation of this work, refer to the parent document. The analysis covers the total Hanford cleanup mission including the decomposition levels at which the various Hanford programs or integrated activities are encountered.

MISSIONS: The Mobile-Based Disaster Mitigation System in Indonesia

Science.gov (United States)

Passarella, Rossi; Putri Raflesia, Sarifah; Lestarini, Dinda; Rifai, Ahmad; Veny, Harumi

2018-04-01

Disaster mitigation is essential to minimize the effects of disasters. Indonesia is one of the disaster prone areas in Asia and the government explores the usage of Information technology (IT) to aid its mitigation efforts. Currently, there are Indonesian websites which hold information regarding the weather monitoring, climate conditions, and geophysics. But, there is no clear indicator of mitigation efforts or things to do during an emergency. Therefore, this research proposed MISSIONS, a disaster mitigation model using geo-fencing technique to detect the location of the users through their mobile devices. MISSIONS uses mobile-based disaster mitigation system as a way to disseminate critical information to victims during emergency when they are in disaster zones using virtual fences. It aims to help the government to reduce the effects of disaster and aid in the mitigation efforts. The implementation result shows that MISSIONS have a high accuracy in detecting user whereabouts.

The Ion Propulsion System for the Solar Electric Propulsion Technology Demonstration Mission

Science.gov (United States)

Herman, Daniel A.; Santiago, Walter; Kamhawi, Hani; Polk, James E.; Snyder, John Steven; Hofer, Richard R.; Parker, J. Morgan

2015-01-01

The Asteroid Redirect Robotic Mission is a candidate Solar Electric Propulsion Technology Demonstration Mission whose main objectives are to develop and demonstrate a high-power solar electric propulsion capability for the Agency and return an asteroidal mass for rendezvous and characterization in a companion human-crewed mission. The ion propulsion system must be capable of operating over an 8-year time period and processing up to 10,000 kg of xenon propellant. This high-power solar electric propulsion capability, or an extensible derivative of it, has been identified as a critical part of an affordable, beyond-low-Earth-orbit, manned-exploration architecture. Under the NASA Space Technology Mission Directorate the critical electric propulsion and solar array technologies are being developed. The ion propulsion system being co-developed by the NASA Glenn Research Center and the Jet Propulsion Laboratory for the Asteroid Redirect Vehicle is based on the NASA-developed 12.5 kW Hall Effect Rocket with Magnetic Shielding (HERMeS0 thruster and power processing technologies. This paper presents the conceptual design for the ion propulsion system, the status of the NASA in-house thruster and power processing activity, and an update on flight hardware.

The MSG Central Facility - A Mission Control System for Windows NT

Science.gov (United States)

Thompson, R.

The MSG Central Facility, being developed by Science Systems for EUMETSAT1, represents the first of a new generation of satellite mission control systems, based on the Windows NT operating system. The system makes use of a range of new technologies to provide an integrated environment for the planning, scheduling, control and monitoring of the entire Meteosat Second Generation mission. It supports packetised TM/TC and uses Science System's Space UNiT product to provide automated operations support at both Schedule (Timeline) and Procedure levels. Flexible access to historical data is provided through an operations archive based on ORACLE Enterprise Server, hosted on a large RAID array and off-line tape jukebox. Event driven real-time data distribution is based on the CORBA standard. Operations preparation and configuration control tools form a fully integrated element of the system.

PHASE ANGLE EFFECTS ON 3 μm ABSORPTION BAND ON CERES: IMPLICATIONS FOR DAWN MISSION

Energy Technology Data Exchange (ETDEWEB)

Takir, D.; Reddy, V.; Sanchez, J. A.; Corre, L. Le [Planetary Science Institute, 1700 E Fort Lowell Road, Suite 106, Tucson, AZ 85719 (United States); Hardersen, P. S. [Department of Space Studies, University of North Dakota, Grand Forks, ND 58202 (United States); Nathues, A., E-mail: dtakir@psi.edu [Max-Planck-Institute for Solar System Research, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany)

2015-05-01

Phase angle-induced spectral effects are important to characterize since they affect spectral band parameters such as band depth and band center, and therefore skew mineralogical interpretations of planetary bodies via reflectance spectroscopy. Dwarf planet (1) Ceres is the next target of NASA’s Dawn mission, which is expected to arrive in 2015 March. The visible and near-infrared mapping spectrometer (VIR) on board Dawn has the spatial and spectral range to characterize the surface between 0.25–5.0 μm. Ceres has an absorption feature at 3.0 μm due to hydroxyl- and/or water-bearing minerals. We analyzed phase angle-induced spectral effects on the 3 μm absorption band on Ceres using spectra measured with the long-wavelength cross-dispersed (LXD: 1.9–4.2 μm) mode of the SpeX spectrograph/imager at the NASA Infrared Telescope Facility. Ceres LXD spectra were measured at different phase angles ranging from 0.°7 to 22°. We found that the band center slightly increases from 3.06 μm at lower phase angles (0.°7 and 6°) to 3.07 μm at higher phase angles (11° and 22°), the band depth decreases by ∼20% from lower phase angles to higher phase angles, and the band area decreases by ∼25% from lower phase angles to higher phase angles. Our results will have implications for constraining the abundance of OH on the surface of Ceres from VIR spectral data, which will be acquired by Dawn starting spring 2015.

PHASE ANGLE EFFECTS ON 3 μm ABSORPTION BAND ON CERES: IMPLICATIONS FOR DAWN MISSION

International Nuclear Information System (INIS)

Takir, D.; Reddy, V.; Sanchez, J. A.; Corre, L. Le; Hardersen, P. S.; Nathues, A.

2015-01-01

Phase angle-induced spectral effects are important to characterize since they affect spectral band parameters such as band depth and band center, and therefore skew mineralogical interpretations of planetary bodies via reflectance spectroscopy. Dwarf planet (1) Ceres is the next target of NASA’s Dawn mission, which is expected to arrive in 2015 March. The visible and near-infrared mapping spectrometer (VIR) on board Dawn has the spatial and spectral range to characterize the surface between 0.25–5.0 μm. Ceres has an absorption feature at 3.0 μm due to hydroxyl- and/or water-bearing minerals. We analyzed phase angle-induced spectral effects on the 3 μm absorption band on Ceres using spectra measured with the long-wavelength cross-dispersed (LXD: 1.9–4.2 μm) mode of the SpeX spectrograph/imager at the NASA Infrared Telescope Facility. Ceres LXD spectra were measured at different phase angles ranging from 0.°7 to 22°. We found that the band center slightly increases from 3.06 μm at lower phase angles (0.°7 and 6°) to 3.07 μm at higher phase angles (11° and 22°), the band depth decreases by ∼20% from lower phase angles to higher phase angles, and the band area decreases by ∼25% from lower phase angles to higher phase angles. Our results will have implications for constraining the abundance of OH on the surface of Ceres from VIR spectral data, which will be acquired by Dawn starting spring 2015

Telecommunications and navigation systems design for manned Mars exploration missions

Science.gov (United States)

Hall, Justin R.; Hastrup, Rolf C.

1989-06-01

This paper discusses typical manned Mars exploration needs for telecommunications, including preliminary navigation support functions. It is a brief progress report on an ongoing study program within the current NASA JPL Deep Space Network (DSN) activities. A typical Mars exploration case is defined, and support approaches comparing microwave and optical frequency performance for both local in situ and Mars-earth links are described. Optical telecommunication and navigation technology development opportunities in a Mars exploration program are also identified. A local Mars system telecommunication relay and navigation capability for service support of all Mars missions has been proposed as part of an overall solar system communications network. The effects of light-time delay and occultations on real-time mission decision-making are discussed; the availability of increased local mass data storage may be more important than increasing peak data rates to earth. The long-term frequency use plan will most likely include a mix of microwave, millimeter-wave and optical link capabilities to meet a variety of deep space mission needs.

NASA 14 Day Undersea Missions: A Short-Duration Spaceflight Analog for Immune System Dysregulation?

Science.gov (United States)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Chouker, A.; Feuerecker, M.; Quiriarte, H.; Pierson, D. L.; Sams, C. F.

2011-01-01

This poster paper reviews the use of 14 day undersea missions as a possible analog for short duration spaceflight for the study of immune system dysregulation. Sixteen subjects from the the NASA Extreme Enviro nment Mission Operations (NEEMO) 12, 13 and 14 missions were studied for immune system dysregulation. The assays that are presented in this poster are the Virleukocyte subsets, the T Cell functions, and the intracellular/secreted cytokine profiles. Other assays were performed, but are not included in this presntation.

Quantum probabilities as Dempster-Shafer probabilities in the lattice of subspaces

International Nuclear Information System (INIS)

Vourdas, A.

2014-01-01

The orthocomplemented modular lattice of subspaces L[H(d)], of a quantum system with d-dimensional Hilbert space H(d), is considered. A generalized additivity relation which holds for Kolmogorov probabilities is violated by quantum probabilities in the full lattice L[H(d)] (it is only valid within the Boolean subalgebras of L[H(d)]). This suggests the use of more general (than Kolmogorov) probability theories, and here the Dempster-Shafer probability theory is adopted. An operator D(H 1 ,H 2 ), which quantifies deviations from Kolmogorov probability theory is introduced, and it is shown to be intimately related to the commutator of the projectors P(H 1 ),P(H 2 ), to the subspaces H 1 , H 2 . As an application, it is shown that the proof of the inequalities of Clauser, Horne, Shimony, and Holt for a system of two spin 1/2 particles is valid for Kolmogorov probabilities, but it is not valid for Dempster-Shafer probabilities. The violation of these inequalities in experiments supports the interpretation of quantum probabilities as Dempster-Shafer probabilities

The closed Brayton cycle: An energy conversion system for near-term military space missions

Science.gov (United States)

Davis, Keith A.

The Particle Bed Reactor (PBR)-closed Brayton cycle (CBC) provides a 5 to 30 kWe class nuclear power system for surveillance and communication missions during the 1990s and will scale to 100 kWe and beyond for other space missions. The PBR-CBC is technically feasible and within the existing state of the art. The PBR-CBC system is flexible, scaleable, and offers development economy. The ability to operate over a wide power range promotes commonality between missions with similar but not identical power spectra. The PBR-CBC system mass is very competitive with rival nuclear dynamic and static power conversion and systems. The PBR-CBC provides growth potential for the future with even lower specific masses.

Interstellar rendezvous missions employing fission propulsion systems

International Nuclear Information System (INIS)

Lenard, Roger X.; Lipinski, Ronald J.

2000-01-01

There has been a conventionally held nostrum that fission system specific power and energy content is insufficient to provide the requisite high accelerations and velocities to enable interstellar rendezvous missions within a reasonable fraction of a human lifetime. As a consequence, all forms of alternative mechanisms that are not yet, and may never be technologically feasible, have been proposed, including laser light sails, fusion and antimatter propulsion systems. In previous efforts, [Lenard and Lipinski, 1999] the authors developed an architecture that employs fission power to propel two different concepts: one, an unmanned probe, the other a crewed vehicle to Alpha Centauri within mission times of 47 to 60 years. The first portion of this paper discusses employing a variant of the ''Forward Resupply Runway'' utilizing fission systems to enable both high accelerations and high final velocities necessary for this type of travel. The authors argue that such an architecture, while expensive, is considerably less expensive and technologically risky than other technologically advanced concepts, and, further, provides the ability to explore near-Earth stellar systems out to distances of 8 light years or so. This enables the ability to establish independent human societies which can later expand the domain of human exploration in roughly eight light-year increments even presuming that no further physics or technology breakthroughs or advances occur. In the second portion of the paper, a technology requirement assessment is performed. The authors argue that reasonable to extensive extensions to known technology could enable this revolutionary capability

Model-Based Systems Engineering for Capturing Mission Architecture System Processes with an Application Case Study - Orion Flight Test 1

Science.gov (United States)

Bonanne, Kevin H.

2011-01-01

Model-based Systems Engineering (MBSE) is an emerging methodology that can be leveraged to enhance many system development processes. MBSE allows for the centralization of an architecture description that would otherwise be stored in various locations and formats, thus simplifying communication among the project stakeholders, inducing commonality in representation, and expediting report generation. This paper outlines the MBSE approach taken to capture the processes of two different, but related, architectures by employing the Systems Modeling Language (SysML) as a standard for architecture description and the modeling tool MagicDraw. The overarching goal of this study was to demonstrate the effectiveness of MBSE as a means of capturing and designing a mission systems architecture. The first portion of the project focused on capturing the necessary system engineering activities that occur when designing, developing, and deploying a mission systems architecture for a space mission. The second part applies activities from the first to an application problem - the system engineering of the Orion Flight Test 1 (OFT-1) End-to-End Information System (EEIS). By modeling the activities required to create a space mission architecture and then implementing those activities in an application problem, the utility of MBSE as an approach to systems engineering can be demonstrated.

Initial Single-Shell Tank Retrieval System mission analysis report

International Nuclear Information System (INIS)

Hertzel, J.S.

1996-03-01

This document provides the mission analysis for the Initial Single-Shell Tank Retrieval System task, which supports the Single-Shell Tank Waste Retrieval Program in its commitment to remove waste from single-shell tanks for treatment and final closure

Ultra Reliable Closed Loop Life Support for Long Space Missions

Science.gov (United States)

Jones, Harry W.; Ewert, Michael K.

2010-01-01

Spacecraft human life support systems can achieve ultra reliability by providing sufficient spares to replace all failed components. The additional mass of spares for ultra reliability is approximately equal to the original system mass, provided that the original system reliability is not too low. Acceptable reliability can be achieved for the Space Shuttle and Space Station by preventive maintenance and by replacing failed units. However, on-demand maintenance and repair requires a logistics supply chain in place to provide the needed spares. In contrast, a Mars or other long space mission must take along all the needed spares, since resupply is not possible. Long missions must achieve ultra reliability, a very low failure rate per hour, since they will take years rather than weeks and cannot be cut short if a failure occurs. Also, distant missions have a much higher mass launch cost per kilogram than near-Earth missions. Achieving ultra reliable spacecraft life support systems with acceptable mass will require a well-planned and extensive development effort. Analysis must determine the reliability requirement and allocate it to subsystems and components. Ultra reliability requires reducing the intrinsic failure causes, providing spares to replace failed components and having "graceful" failure modes. Technologies, components, and materials must be selected and designed for high reliability. Long duration testing is needed to confirm very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The system must be designed, developed, integrated, and tested with system reliability in mind. Maintenance and reparability of failed units must not add to the probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass should start soon since it must be a long term effort.

NASA Intelligent Systems Project: Results, Accomplishments and Impact on Science Missions

Science.gov (United States)

Coughlan, Joseph C.

2005-01-01

The Intelligent Systems Project was responsible for much of NASA's programmatic investment in artificial intelligence and advanced information technologies. IS has completed three major project milestones which demonstrated increased capabilities in autonomy, human centered computing, and intelligent data understanding. Autonomy involves the ability of a robot to place an instrument on a remote surface with a single command cycle. Human centered computing supported a collaborative, mission centric data and planning system for the Mars Exploration Rovers and data understanding has produced key components of a terrestrial satellite observation system with automated modeling and data analysis capabilities. This paper summarizes the technology demonstrations and metrics which quantify and summarize these new technologies which are now available for future Nasa missions.

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Colombia. February - March 1980

International Nuclear Information System (INIS)

Cameron, J.; Meunier, A.R.; Tauchid, M.

1980-01-01

The basic objective of IUREP is to 'review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for discovery of additional uranium resources, and to suggest new exploration efforts which might be carried out in promising new areas in collaboration with the countries concerned'. Following the initial bibliographic study, which formed Phase I of IUREP, it was envisaged that a further assessment in co-operation with the country in question would lead to a better delineation of areas of high potential and a more reliable estimate as to the degree of favourability for the discovery of additional uranium resources. It was planned that such work would be accomplished through field missions to the country and that these field missions and the resulting report would constitute the IUREP Orientation Phase. The purpose of the Orientation Mission to Colombia was (i) to develop a better understanding of the uranium potential of the country, (ii) to delineate areas favourable for the discovery of speculative uranium resources, (iii) to make recommendations, as appropriate, on the best methods for evaluating the favourable areas, operating procedures and estimated possible costs, (iv) to develop the logistical data required to carry out any possible further work, and (v) to compile a report that would be immediately available to the Colombian authorities. Uranium exploration in Colombia is of very recent date, with the majority of activities getting under way only after 1970. In spite of the limited work that has been done, however, over 1300 radioactive anomalies have been recorded. The total number of uranium mineral occurrences resulting from follow-up work is still very small, and some are unusual in world terms. Topographic and geographic conditions in Colombia make geological and exploration work very difficult and costly, especially in the Cordilleras and the Interior Zone (Llanos Orientales). There are, at

Estimating Impact and Frequency of Risks to Safety and Mission Critical Systems Using CVSS

NARCIS (Netherlands)

Houmb, S.H.; Nunes Leal Franqueira, V.; Engum, E.A.

2008-01-01

Many safety and mission critical systems depend on the correct and secure operation of both supportive and core software systems. E.g., both the safety of personnel and the effective execution of core missions on an oil platform depend on the correct recording storing, transfer and interpretation of

Potential large missions enabled by NASA's space launch system

Science.gov (United States)

Stahl, H. Philip; Hopkins, Randall C.; Schnell, Andrew; Smith, David A.; Jackman, Angela; Warfield, Keith R.

2016-07-01

Large space telescope missions have always been limited by their launch vehicle's mass and volume capacities. The Hubble Space Telescope (HST) was specifically designed to fit inside the Space Shuttle and the James Webb Space Telescope (JWST) is specifically designed to fit inside an Ariane 5. Astrophysicists desire even larger space telescopes. NASA's "Enduring Quests Daring Visions" report calls for an 8- to 16-m Large UV-Optical-IR (LUVOIR) Surveyor mission to enable ultra-high-contrast spectroscopy and coronagraphy. AURA's "From Cosmic Birth to Living Earth" report calls for a 12-m class High-Definition Space Telescope to pursue transformational scientific discoveries. NASA's "Planning for the 2020 Decadal Survey" calls for a Habitable Exoplanet Imaging (HabEx) and a LUVOIR as well as Far-IR and an X-Ray Surveyor missions. Packaging larger space telescopes into existing launch vehicles is a significant engineering complexity challenge that drives cost and risk. NASA's planned Space Launch System (SLS), with its 8 or 10-m diameter fairings and ability to deliver 35 to 45-mt of payload to Sun-Earth-Lagrange-2, mitigates this challenge by fundamentally changing the design paradigm for large space telescopes. This paper reviews the mass and volume capacities of the planned SLS, discusses potential implications of these capacities for designing large space telescope missions, and gives three specific mission concept implementation examples: a 4-m monolithic off-axis telescope, an 8-m monolithic on-axis telescope and a 12-m segmented on-axis telescope.

Predicting critical transitions in dynamical systems from time series using nonstationary probability density modeling.

Science.gov (United States)

Kwasniok, Frank

2013-11-01

A time series analysis method for predicting the probability density of a dynamical system is proposed. A nonstationary parametric model of the probability density is estimated from data within a maximum likelihood framework and then extrapolated to forecast the future probability density and explore the system for critical transitions or tipping points. A full systematic account of parameter uncertainty is taken. The technique is generic, independent of the underlying dynamics of the system. The method is verified on simulated data and then applied to prediction of Arctic sea-ice extent.

Benefits to the Europa Clipper Mission Provided by the Space Launch System

Science.gov (United States)

Creech, Stephen D.; Patel, Keyur

2013-01-01

The National Aeronautics and Space Administration's (NASA's) proposed Europa Clipper mission would provide an unprecedented look at the icy Jovian moon, and investigate its environment to determine the possibility that it hosts life. Focused on exploring the water, chemistry, and energy conditions on the moon, the spacecraft would examine Europa's ocean, ice shell, composition and geology by performing 32 low-altitude flybys of Europa from Jupiter orbit over 2.3 years, allowing detailed investigations of globally distributed regions of Europa. In hopes of expediting the scientific program, mission planners at NASA's Jet Propulsion Laboratory are working with the Space Launch System (SLS) program, managed at Marshall Space Flight Center. Designed to be the most powerful launch vehicle ever flown, SLS is making progress toward delivering a new capability for exploration beyond Earth orbit. The SLS rocket will offer an initial low-Earth-orbit lift capability of 70 metric tons (t) beginning with a first launch in 2017 and will then evolve into a 130 t Block 2 version. While the primary focus of the development of the initial version of SLS is on enabling human exploration missions beyond low Earth orbit using the Orion Multi-Purpose Crew Vehicle, the rocket offers unique benefits to robotic planetary exploration missions, thanks to the high characteristic energy it provides. This paper will provide an overview of both the proposed Europa Clipper mission and the Space Launch System vehicle, and explore options provided to the Europa Clipper mission for a launch within a decade by a 70 t version of SLS with a commercially available 5-meter payload fairing, through comparison with a baseline of current Evolved Expendable Launch Vehicle (EELV) capabilities. Compared to that baseline, a mission to the Jovian system could reduce transit times to less than half, or increase mass to more than double, among other benefits. In addition to these primary benefits, the paper will

A computer graphics pilot project - Spacecraft mission support with an interactive graphics workstation

Science.gov (United States)

Hagedorn, John; Ehrner, Marie-Jacqueline; Reese, Jodi; Chang, Kan; Tseng, Irene

1986-01-01

The NASA Computer Graphics Pilot Project was undertaken to enhance the quality control, productivity and efficiency of mission support operations at the Goddard Operations Support Computing Facility. The Project evolved into a set of demonstration programs for graphics intensive simulated control room operations, particularly in connection with the complex space missions that began in the 1980s. Complex mission mean more data. Graphic displays are a means to reduce the probabilities of operator errors. Workstations were selected with 1024 x 768 pixel color displays controlled by a custom VLSI chip coupled to an MC68010 chip running UNIX within a shell that permits operations through the medium of mouse-accessed pulldown window menus. The distributed workstations run off a host NAS 8040 computer. Applications of the system for tracking spacecraft orbits and monitoring Shuttle payload handling illustrate the system capabilities, noting the built-in capabilities of shifting the point of view and rotating and zooming in on three-dimensional views of spacecraft.

JSpOC Mission System Application Development Environment

Science.gov (United States)

Luce, R.; Reele, P.; Sabol, C.; Zetocha, P.; Echeverry, J.; Kim, R.; Golf, B.

2012-09-01

The Joint Space Operations Center (JSpOC) Mission System (JMS) is the program of record tasked with replacing the legacy Space Defense Operations Center (SPADOC) and Astrodynamics Support Workstation (ASW) capabilities by the end of FY2015 as well as providing additional Space Situational Awareness (SSA) and Command and Control (C2) capabilities post-FY2015. To meet the legacy replacement goal, the JMS program is maturing a government Service Oriented Architecture (SOA) infrastructure that supports the integration of mission applications while acquiring mature industry and government mission applications. Future capabilities required by the JSpOC after 2015 will require development of new applications and procedures as well as the exploitation of new SSA data sources. To support the post FY2015 efforts, the JMS program is partnering with the Air Force Research Laboratory (AFRL) to build a JMS application development environment. The purpose of this environment is to: 1) empower the research & development community, through access to relevant tools and data, to accelerate technology development, 2) allow the JMS program to communicate user capability priorities and requirements to the developer community, 3) provide the JMS program with access to state-of-the-art research, development, and computing capabilities, and 4) support market research efforts by identifying outstanding performers that are available to shepherd into the formal transition process. The application development environment will consist of both unclassified and classified environments that can be accessed over common networks (including the Internet) to provide software developers, scientists, and engineers everything they need (e.g., building block JMS services, modeling and simulation tools, relevant test scenarios, documentation, data sources, user priorities/requirements, and SOA integration tools) to develop and test mission applications. The developed applications will be exercised in these

Mission and System Advantages of Iodine Hall Thrusters

Science.gov (United States)

Dankanich, John W.; Szabo, James; Pote, Bruce; Oleson, Steve; Kamhawi, Hani

2014-01-01

The exploration of alternative propellants for Hall thrusters continues to be of interest to the community. Investments have been made and continue for the maturation of iodine based Hall thrusters. Iodine testing has shown comparable performance to xenon. However, iodine has a higher storage density and resulting higher ?V capability for volume constrained systems. Iodine's vapor pressure is low enough to permit low-pressure storage, but high enough to minimize potential adverse spacecraft-thruster interactions. The low vapor pressure also means that iodine does not condense inside the thruster at ordinary operating temperatures. Iodine is safe, it stores at sub-atmospheric pressure, and can be stored unregulated for years on end; whether on the ground or on orbit. Iodine fills a niche for both low power (10kW) electric propulsion regimes. A range of missions have been evaluated for direct comparison of Iodine and Xenon options. The results show advantages of iodine Hall systems for both small and microsatellite application and for very large exploration class missions.

Meteosat third generation: preliminary imagery and sounding mission concepts and performances

Science.gov (United States)

Aminou, Donny M.; Bézy, Jean-Loup; Bensi, Paolo; Stuhlmann, Rolf; Rodriguez, Antonio

2017-11-01

The operational deployment of MSG-1 at the beginning of 2004, the first of a series of four Meteosat Second Generation (MSG) satellites, marks the start of a new era in Europe for the meteorological observations from the geostationary orbit. This new system shall be the backbone of the European operational meteorological services up to at least 2015. The time required for the definition and the development of new space systems as well as the approval process of such complex programs implies to plan well ahead for the future missions. EUMETSAT have initiated in 2001, with ESA support, a User Consultation Process aiming at preparing for a future operational geostationary meteorological satellite system in the post-MSG era, named Meteosat Third Generation (MTG). The first phase of the User Consultation Process was devoted to the definition and consolidation of end user requirements and priorities in the field of Nowcasting and Very Short Term Weather Forecasting (NWC), Medium/Short Range global and regional Numerical Weather Prediction (NWP), Climate and Air Composition Monitoring and to the definition of the relevant observation techniques. After an initial post-MSG mission study (2003-2004) where preliminary instrument concepts were investigated allowing in the same time to consolidate the technical requirements for the overall system study, a MTG pre-phase A study has been performed for the overall system concept, architecture and programmatic aspects during 2004-2005 time frame. This paper provides an overview of the outcome of the MTG sensor concept studies conducted in the frame of the pre-phase A. It namely focuses onto the Imaging and Sounding Missions, highlights the resulting instrument concepts, establishes the critical technologies and introduces the study steps towards the implementation of the MTG development programme.

Computer-aided mathematical analysis of probability of intercept for ground-based communication intercept system

Science.gov (United States)

Park, Sang Chul

1989-09-01

We develop a mathematical analysis model to calculate the probability of intercept (POI) for the ground-based communication intercept (COMINT) system. The POI is a measure of the effectiveness of the intercept system. We define the POI as the product of the probability of detection and the probability of coincidence. The probability of detection is a measure of the receiver's capability to detect a signal in the presence of noise. The probability of coincidence is the probability that an intercept system is available, actively listening in the proper frequency band, in the right direction and at the same time that the signal is received. We investigate the behavior of the POI with respect to the observation time, the separation distance, antenna elevations, the frequency of the signal, and the receiver bandwidths. We observe that the coincidence characteristic between the receiver scanning parameters and the signal parameters is the key factor to determine the time to obtain a given POI. This model can be used to find the optimal parameter combination to maximize the POI in a given scenario. We expand this model to a multiple system. This analysis is conducted on a personal computer to provide the portability. The model is also flexible and can be easily implemented under different situations.

Medical and technology requirements for human solar system exploration missions

Science.gov (United States)

Nicogossian, Arnauld; Harris, Leonard; Couch, Lana; Sulzman, Frank; Gaiser, Karen

1989-01-01

Measures that need to be taken to cope with the health problems posed by zero gravity and radiation in manned solar system exploration missions are discussed. The particular systems that will be used aboard Space Station Freedom are addressed, and relevant human factors problems are examined. The development of a controlled ecological life support system is addressed.

Input-profile-based software failure probability quantification for safety signal generation systems

International Nuclear Information System (INIS)

Kang, Hyun Gook; Lim, Ho Gon; Lee, Ho Jung; Kim, Man Cheol; Jang, Seung Cheol

2009-01-01

The approaches for software failure probability estimation are mainly based on the results of testing. Test cases represent the inputs, which are encountered in an actual use. The test inputs for the safety-critical application such as a reactor protection system (RPS) of a nuclear power plant are the inputs which cause the activation of protective action such as a reactor trip. A digital system treats inputs from instrumentation sensors as discrete digital values by using an analog-to-digital converter. Input profile must be determined in consideration of these characteristics for effective software failure probability quantification. Another important characteristic of software testing is that we do not have to repeat the test for the same input value since the software response is deterministic for each specific digital input. With these considerations, we propose an effective software testing method for quantifying the failure probability. As an example application, the input profile of the digital RPS is developed based on the typical plant data. The proposed method in this study is expected to provide a simple but realistic mean to quantify the software failure probability based on input profile and system dynamics.

In-Space Propulsion Technology Products for NASA's Future Science and Exploration Missions

Science.gov (United States)

Anderson, David J.; Pencil, Eric; Peterson, Todd; Dankanich, John; Munk, Michelle M.

2011-01-01

Since 2001, the In-Space Propulsion Technology (ISPT) project has been developing and delivering in-space propulsion technologies that will enable or enhance NASA robotic science missions. These in-space propulsion technologies are applicable, and potentially enabling, for future NASA flagship and sample return missions currently being considered, as well as having broad applicability to future competed mission solicitations. The high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost was completed in 2009. Two other ISPT technologies are nearing completion of their technology development phase: 1) NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 2) Aerocapture technology development with investments in a family of thermal protection system (TPS) materials and structures; guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; aerothermal effect models: and atmospheric models for Earth, Titan, Mars and Venus. This paper provides status of the technology development, applicability, and availability of in-space propulsion technologies that have recently completed their technology development and will be ready for infusion into NASA s Discovery, New Frontiers, Science Mission Directorate (SMD) Flagship, and Exploration technology demonstration missions

RICIS Symposium 1992: Mission and Safety Critical Systems Research and Applications

Science.gov (United States)

1992-01-01

This conference deals with computer systems which control systems whose failure to operate correctly could produce the loss of life and or property, mission and safety critical systems. Topics covered are: the work of standards groups, computer systems design and architecture, software reliability, process control systems, knowledge based expert systems, and computer and telecommunication protocols.

Auto Mission Planning System Design for Imaging Satellites and Its Applications in Environmental Field

Directory of Open Access Journals (Sweden)

He Yongming

2016-10-01

Full Text Available Satellite hardware has reached a level of development that enables imaging satellites to realize applications in the area of meteorology and environmental monitoring. As the requirements in terms of feasibility and the actual profit achieved by satellite applications increase, we need to comprehensively consider the actual status, constraints, unpredictable information, and complicated requirements. The management of this complex information and the allocation of satellite resources to realize image acquisition have become essential for enhancing the efficiency of satellite instrumentation. In view of this, we designed a satellite auto mission planning system, which includes two sub-systems: the imaging satellite itself and the ground base, and these systems would then collaborate to process complicated missions: the satellite mainly focuses on mission planning and functions according to actual parameters, whereas the ground base provides auxiliary information, management, and control. Based on the requirements analysis, we have devised the application scenarios, main module, and key techniques. Comparison of the simulation results of the system, confirmed the feasibility and optimization efficiency of the system framework, which also stimulates new thinking for the method of monitoring environment and design of mission planning systems.

Multiagent Modeling and Simulation in Human-Robot Mission Operations Work System Design

Science.gov (United States)

Sierhuis, Maarten; Clancey, William J.; Sims, Michael H.; Shafto, Michael (Technical Monitor)

2001-01-01

This paper describes a collaborative multiagent modeling and simulation approach for designing work systems. The Brahms environment is used to model mission operations for a semi-autonomous robot mission to the Moon at the work practice level. It shows the impact of human-decision making on the activities and energy consumption of a robot. A collaborative work systems design methodology is described that allows informal models, created with users and stakeholders, to be used as input to the development of formal computational models.

Creating a mission-based reporting system at an academic health center.

Science.gov (United States)

Howell, Lydia Pleotis; Hogarth, Michael; Anders, Thomas F

2002-02-01

The authors developed a Web-based mission-based reporting (MBR) system for their university's (UC Davis's) health system to report faculty members' activities in research and creative work, clinical service, education, and community/university service. They developed the system over several years (1998-2001) in response to a perceived need to better define faculty members' productivity for faculty development, financial management, and program assessment. The goal was to create a measurement tool that could be used by department chairs to counsel faculty on their performances. The MBR system provides measures of effort for each of the university's four missions. Departments or the school can use the output to better define expenditures and allocations of resources. The system provides both a quantitative metric of times spent on various activities within each mission, and a qualitative metric for the effort expended. The authors report the process of developing the MBR system and making it applicable for both clinical and basic science departments, and the mixed success experienced in its implementation. The system appears to depict the activities of most faculty fairly accurately, and chairs of test departments have been generally enthusiastic. However, resistance to general implementation remains, chiefly due to concerns about reliability, validity, and time required for completing the report. The authors conclude that MBR can be useful but will require some streamlining and the elimination of other redundant reporting instruments. A well-defined purpose is required to motivate its use.

Cluster geometry and survival probability in systems driven by reaction-diffusion dynamics

International Nuclear Information System (INIS)

Windus, Alastair; Jensen, Henrik J

2008-01-01

We consider a reaction-diffusion model incorporating the reactions A→φ, A→2A and 2A→3A. Depending on the relative rates for sexual and asexual reproduction of the quantity A, the model exhibits either a continuous or first-order absorbing phase transition to an extinct state. A tricritical point separates the two phase lines. While we comment on this critical behaviour, the main focus of the paper is on the geometry of the population clusters that form. We observe the different cluster structures that arise at criticality for the three different types of critical behaviour and show that there exists a linear relationship for the survival probability against initial cluster size at the tricritical point only.

Fission Power System Technology for NASA Exploration Missions

Science.gov (United States)

Mason, Lee; Houts, Michael

2011-01-01

Under the NASA Exploration Technology Development Program, and in partnership with the Department of Energy (DOE), NASA is conducting a project to mature Fission Power System (FPS) technology. A primary project goal is to develop viable system options to support future NASA mission needs for nuclear power. The main FPS project objectives are as follows: 1) Develop FPS concepts that meet expected NASA mission power requirements at reasonable cost with added benefits over other options. 2) Establish a hardware-based technical foundation for FPS design concepts and reduce overall development risk. 3) Reduce the cost uncertainties for FPS and establish greater credibility for flight system cost estimates. 4) Generate the key products to allow NASA decisionmakers to consider FPS as a preferred option for flight development. In order to achieve these goals, the FPS project has two main thrusts: concept definition and risk reduction. Under concept definition, NASA and DOE are performing trade studies, defining requirements, developing analytical tools, and formulating system concepts. A typical FPS consists of the reactor, shield, power conversion, heat rejection, and power management and distribution (PMAD). Studies are performed to identify the desired design parameters for each subsystem that allow the system to meet the requirements with reasonable cost and development risk. Risk reduction provides the means to evaluate technologies in a laboratory test environment. Non-nuclear hardware prototypes are built and tested to verify performance expectations, gain operating experience, and resolve design uncertainties.

ESPA for Lunar and Science Missions, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — NASA mission planning in the next decade includes small spacecraft and secondary flight opportunities on Evolved Expendable Launch Vehicles (EELVs), specifically...

A philosophical essay on probabilities

CERN Document Server

Laplace, Marquis de

1996-01-01

A classic of science, this famous essay by ""the Newton of France"" introduces lay readers to the concepts and uses of probability theory. It is of especial interest today as an application of mathematical techniques to problems in social and biological sciences.Generally recognized as the founder of the modern phase of probability theory, Laplace here applies the principles and general results of his theory ""to the most important questions of life, which are, in effect, for the most part, problems in probability."" Thus, without the use of higher mathematics, he demonstrates the application

Tank waste remediation system retrieval and disposal mission - Phase 1: Financial analysis

International Nuclear Information System (INIS)

Bickford, J.C.

1998-01-01

In Section 1.0, an overview of the Financial Analysis was provided and summarized in Table 1 for both the Retrieval and Disposal program and the TWRS project life cycle. A table recaps the pre-Phase 1B analysis budget requirements as discussed in previous sections. Another table in this section shows a similar build-up of costs and the impact of proposed offsets and increases to the pre-Phase 1B analysis. The issues concerning the increased requirements in FY 1998/1999 and the recommended adjustments were discussed. The Phase 1B Program as recommended is achievable. Specific recommendations are as follows: (a) Adopt the revised project baseline as presented in the cited tables; (b) Incorporate the $248.5 million in allowances for risk into the baseline; (c) Develop detailed action plans to realize the costs reduction opportunities; (d) Incorporate site indirect and benefits reduction rates into baseline; (e) Delay non-critical path scope which can be moved beyond FY 1999, as indicated: and (f) Renegotiate the Tri-Party Agreement milestones associated with the current compliance unfunded list for FY 1998

A Probability-Based Hybrid User Model for Recommendation System

Directory of Open Access Journals (Sweden)

Jia Hao

2016-01-01

Full Text Available With the rapid development of information communication technology, the available information or knowledge is exponentially increased, and this causes the well-known information overload phenomenon. This problem is more serious in product design corporations because over half of the valuable design time is consumed in knowledge acquisition, which highly extends the design cycle and weakens the competitiveness. Therefore, the recommender systems become very important in the domain of product domain. This research presents a probability-based hybrid user model, which is a combination of collaborative filtering and content-based filtering. This hybrid model utilizes user ratings and item topics or classes, which are available in the domain of product design, to predict the knowledge requirement. The comprehensive analysis of the experimental results shows that the proposed method gains better performance in most of the parameter settings. This work contributes a probability-based method to the community for implement recommender system when only user ratings and item topics are available.

GPS test range mission planning

Science.gov (United States)

Roberts, Iris P.; Hancock, Thomas P.

The principal features of the Test Range User Mission Planner (TRUMP), a PC-resident tool designed to aid in deploying and utilizing GPS-based test range assets, are reviewed. TRUMP features time history plots of time-space-position information (TSPI); performance based on a dynamic GPS/inertial system simulation; time history plots of TSPI data link connectivity; digital terrain elevation data maps with user-defined cultural features; and two-dimensional coverage plots of ground-based test range assets. Some functions to be added during the next development phase are discussed.

Kepler: NASA's First Mission Capable of Finding Earth-Size Planets

Science.gov (United States)

Borucki, William J.

2009-01-01

Kepler, a NASA Discovery mission, is a spaceborne telescope designed to search a nearby region of our galaxy for Earth-size planets orbiting in the habitable zone of stars like our sun. The habitable zone is that region around a start where the temperature permits water to be liquid on the surface of a planet. Liquid water is considered essential forth existence of life. Mission Phases: Six mission phases have been defined to describe the different periods of activity during Kepler's mission. These are: launch; commissioning; early science operations, science operations: and decommissioning

A Mission Planning Approach for Precision Farming Systems Based on Multi-Objective Optimization

Directory of Open Access Journals (Sweden)

Zhaoyu Zhai

2018-06-01

Full Text Available As the demand for food grows continuously, intelligent agriculture has drawn much attention due to its capability of producing great quantities of food efficiently. The main purpose of intelligent agriculture is to plan agricultural missions properly and use limited resources reasonably with minor human intervention. This paper proposes a Precision Farming System (PFS as a Multi-Agent System (MAS. Components of PFS are treated as agents with different functionalities. These agents could form several coalitions to complete the complex agricultural missions cooperatively. In PFS, mission planning should consider several criteria, like expected benefit, energy consumption or equipment loss. Hence, mission planning could be treated as a Multi-objective Optimization Problem (MOP. In order to solve MOP, an improved algorithm, MP-PSOGA, is proposed, taking advantages of the Genetic Algorithms and Particle Swarm Optimization. A simulation, called precise pesticide spraying mission, is performed to verify the feasibility of the proposed approach. Simulation results illustrate that the proposed approach works properly. This approach enables the PFS to plan missions and allocate scarce resources efficiently. The theoretical analysis and simulation is a good foundation for the future study. Once the proposed approach is applied to a real scenario, it is expected to bring significant economic improvement.

Phase Control in Nonlinear Systems

Science.gov (United States)

Zambrano, Samuel; Seoane, Jesús M.; Mariño, Inés P.; Sanjuán, Miguel A. F.; Meucci, Riccardo

The following sections are included: * Introduction * Phase Control of Chaos * Description of the model * Numerical exploration of phase control of chaos * Experimental evidence of phase control of chaos * Phase Control of Intermittency in Dynamical Systems * Crisis-induced intermittency and its control * Experimental setup and implementation of the phase control scheme * Phase control of the laser in the pre-crisis regime * Phase control of the intermittency after the crisis * Phase control of the intermittency in the quadratic map * Phase Control of Escapes in Open Dynamical Systems * Control of open dynamical systems * Model description * Numerical simulations and heuristic arguments * Experimental implementation in an electronic circuit * Conclusions and Discussions * Acknowledgments * References

Use of two-phase flow heat transfer method in spacecraft thermal system

Science.gov (United States)

Hye, A.

1985-01-01

In space applications, weight, volume and power are critical parameters. Presently liquid freon is used in the radiator planels of the Space Shuttle to dissipate heat. This requires a large amount of freon, large power for pumps, large volume and weight. Use of two-phase flow method to transfer heat can reduce them significantly. A modified commercial vapor compression refrigerator/freezer was sucessfully flown in STS-4 to study the effect of zero-gravity on the system. The duty cycle was about 5 percent higher in flight as compared to that on earth due to low flow velocity in condenser. The vapor Reynolds number at exit was about 4000 as compared to about 12,000. Efforts are underway to design a refrigerator/freezer using an oil-free compressor for Spacelab Mission 4 scheduled to fly in January 1986. A thermal system can be designed for spacecraft using the two-phase flow to transfer heat economically.

Mission operations concepts for Earth Observing System (EOS)

Science.gov (United States)

Kelly, Angelita C.; Taylor, Thomas D.; Hawkins, Frederick J.

1991-01-01

Mission operation concepts are described which are being used to evaluate and influence space and ground system designs and architectures with the goal of achieving successful, efficient, and cost-effective Earth Observing System (EOS) operations. Emphasis is given to the general characteristics and concepts developed for the EOS Space Measurement System, which uses a new series of polar-orbiting observatories. Data rates are given for various instruments. Some of the operations concepts which require a total system view are also examined, including command operations, data processing, data accountability, data archival, prelaunch testing and readiness, launch, performance monitoring and assessment, contingency operations, flight software maintenance, and security.

Tank Waste Remediation System retrieval and disposal mission technical baseline summary description

International Nuclear Information System (INIS)

McLaughlin, T.J.

1998-01-01

This document is prepared in order to support the US Department of Energy's evaluation of readiness-to-proceed for the Waste Retrieval and Disposal Mission at the Hanford Site. The Waste Retrieval and Disposal Mission is one of three primary missions under the Tank Waste Remediation System (TWRS) Project. The other two include programs to characterize tank waste and to provide for safe storage of the waste while it awaits treatment and disposal. The Waste Retrieval and Disposal Mission includes the programs necessary to support tank waste retrieval, wastefeed, delivery, storage and disposal of immobilized waste, and closure of tank farms. This mission will enable the tank farms to be closed and turned over for final remediation. The Technical Baseline is defined as the set of science and engineering, equipment, facilities, materials, qualified staff, and enabling documentation needed to start up and complete the mission objectives. The primary purposes of this document are (1) to identify the important technical information and factors that should be used by contributors to the mission and (2) to serve as a basis for configuration management of the technical information and factors

Exploring with PAM: Prospecting ANTS Missions for Solar System Surveys

Science.gov (United States)

Clark, P. E.; Rilee, M. L.; Curtis, S. A.

2003-01-01

ANTS (Autonomous Nano-Technology Swarm), a large (1000 member) swarm of nano to picoclass (10 to 1 kg) totally autonomous spacecraft, are being developed as a NASA advanced mission concept. ANTS, based on a hierarchical insect social order, use an evolvable, self-similar, hierarchical neural system in which individual spacecraft represent the highest level nodes. ANTS uses swarm intelligence attained through collective, cooperative interactions of the nodes at all levels of the system. At the highest levels this can take the form of cooperative, collective behavior among the individual spacecraft in a very large constellation. The ANTS neural architecture is designed for totally autonomous operation of complex systems including spacecraft constellations. The ANTS (Autonomous Nano Technology Swarm) concept has a number of possible applications. A version of ANTS designed for surveying and determining the resource potential of the asteroid belt, called PAM (Prospecting ANTS Mission), is examined here.

Reliability analysis of reactor systems by applying probability method; Analiza pouzdanosti reaktorskih sistema primenom metoda verovatnoce

Energy Technology Data Exchange (ETDEWEB)

Milivojevic, S [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1974-12-15

Probability method was chosen for analysing the reactor system reliability is considered realistic since it is based on verified experimental data. In fact this is a statistical method. The probability method developed takes into account the probability distribution of permitted levels of relevant parameters and their particular influence on the reliability of the system as a whole. The proposed method is rather general, and was used for problem of thermal safety analysis of reactor system. This analysis enables to analyze basic properties of the system under different operation conditions, expressed in form of probability they show the reliability of the system on the whole as well as reliability of each component.

Jupiter Icy Moons Explorer (JUICE) : Science Objectives, Mission and Instruments (abstract)

NARCIS (Netherlands)

Gurvits, L.; Plaut, J.J.; Barabash, S.; Bruzzone, L.; Dougherty, M.; Erd, C.; Fletcher, L.; Gladstone, R.; Grasset, O.; Hartogh, P.; Hussmann, H.; Iess, L.; Jaumann, R.; Langevin, Y.; Palumbo, P.; Piccioni, G.; Titov, D.; Wahlund, J.E.

2014-01-01

The JUpiter ICy Moons Explorer (JUICE) is a European Space Agency mission that will fly by and observe the Galilean satellites Europa, Ganymede and Callisto, characterize the Jovian system in a lengthy Jupiter-orbit phase, and ultimately orbit Ganymede for in-depth studies of habitability, evolution

High Voltage Hall Accelerator Propulsion System Development for NASA Science Missions

Science.gov (United States)

Kamhawi, Hani; Haag, Thomas; Huang, Wensheng; Shastry, Rohit; Pinero, Luis; Peterson, Todd; Dankanich, John; Mathers, Alex

2013-01-01

NASA Science Mission Directorates In-Space Propulsion Technology Program is sponsoring the development of a 3.8 kW-class engineering development unit Hall thruster for implementation in NASA science and exploration missions. NASA Glenn Research Center and Aerojet are developing a high fidelity high voltage Hall accelerator (HiVHAc) thruster that can achieve specific impulse magnitudes greater than 2,700 seconds and xenon throughput capability in excess of 300 kilograms. Performance, plume mappings, thermal characterization, and vibration tests of the HiVHAc engineering development unit thruster have been performed. In addition, the HiVHAc project is also pursuing the development of a power processing unit (PPU) and xenon feed system (XFS) for integration with the HiVHAc engineering development unit thruster. Colorado Power Electronics and NASA Glenn Research Center have tested a brassboard PPU for more than 1,500 hours in a vacuum environment, and a new brassboard and engineering model PPU units are under development. VACCO Industries developed a xenon flow control module which has undergone qualification testing and will be integrated with the HiVHAc thruster extended duration tests. Finally, recent mission studies have shown that the HiVHAc propulsion system has sufficient performance for four Discovery- and two New Frontiers-class NASA design reference missions.

The Simbol-X Mission

Science.gov (United States)

Ferrando, P.; Arnaud, M.; Briel, U.; Cavazzuti, E.; Clédassou, R.; Counil, J. L.; Fiore, F.; Giommi, P.; Goldwurm, A.; Lamarle, O.; Laurent, P.; Lebrun, F.; Malaguti, G.; Mereghetti, S.; Micela, G.; Pareschi, G.; Piermaria, M.; Roques, J. P.; Santangelo, A.; Tagliaferri, G.

2009-05-01

The elucidation of key questions in astrophysics, in particular those related to black hole physics and census, and to particle acceleration mechanisms, necessitates to develop new observational capabilities in the hard X-ray domain with performances several orders of magnitude better than presently available. Relying on two spacecrafts in a formation flying configuration, Simbol-X will provide the world-wide astrophysics community with a single optics long focal length telescope. This observatory will have unrivaled performances in the hard X-ray domain, up to ~80 keV, as well as very good characteristics in the soft X-ray domain, down to ~0.5 keV. The Simbol-X mission has successfully passed a phase A study, jointly conducted by CNES and ASI, with the participation of German laboratories. It is now entering phase B studies with the participation of new international partners, for a launch in 2015. We give in this paper a general overview of the mission, as consolidated at the start of phase B.

Comparison of Cerebral Glucose Metabolism between Possible and Probable Multiple System Atrophy

Directory of Open Access Journals (Sweden)

Kyum-Yil Kwon

2009-05-01

Full Text Available Background: To investigate the relationship between presenting clinical manifestations and imaging features of multisystem neuronal dysfunction in MSA patients, using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET. Methods: We studied 50 consecutive MSA patients with characteristic brain MRI findings of MSA, including 34 patients with early MSA-parkinsonian (MSA-P and 16 with early MSA-cerebellar (MSA-C. The cerebral glucose metabolism of all MSA patients was evaluated in comparison with 25 age-matched controls. 18F-FDG PET results were assessed by the Statistic Parametric Mapping (SPM analysis and the regions of interest (ROI method. Results: The mean time from disease onset to 18F-FDG PET was 25.9±13.0 months in 34 MSA-P patients and 20.1±11.1 months in 16 MSA-C patients. Glucose metabolism of the putamen showed a greater decrease in possible MSA-P than in probable MSA-P (p=0.031. Although the Unified Multiple System Atrophy Rating Scale (UMSARS score did not differ between possible MSA-P and probable MSA-P, the subscores of rigidity (p=0.04 and bradykinesia (p= 0.008 were significantly higher in possible MSA-P than in probable MSA-P. Possible MSA-C showed a greater decrease in glucose metabolism of the cerebellum than probable MSA-C (p=0.016. Conclusions: Our results may suggest that the early neuropathological pattern of possible MSA with a predilection for the striatonigral or olivopontocerebellar system differs from that of probable MSA, which has prominent involvement of the autonomic nervous system in addition to the striatonigral or olivopontocerebellar system.

Advanced Exploration Systems Water Architecture Study Interim Results

Science.gov (United States)

Sargusingh, Miriam J.

2013-01-01

The mission of the Advanced Exploration System (AES) Water Recovery Project (WRP) is to develop advanced water recovery systems that enable NASA human exploration missions beyond low Earth orbit (LEO). The primary objective of the AES WRP is to develop water recovery technologies critical to near-term missions beyond LEO. The secondary objective is to continue to advance mid-readiness-level technologies to support future NASA missions. An effort is being undertaken to establish the architecture for the AES Water Recovery System (WRS) that meets both near- and long-term objectives. The resultant architecture will be used to guide future technical planning, establish a baseline development roadmap for technology infusion, and establish baseline assumptions for integrated ground and on-orbit Environmental Control and Life Support Systems definition. This study is being performed in three phases. Phase I established the scope of the study through definition of the mission requirements and constraints, as well as identifying all possible WRS configurations that meet the mission requirements. Phase II focused on the near-term space exploration objectives by establishing an International Space Station-derived reference schematic for long-duration (>180 day) in-space habitation. Phase III will focus on the long-term space exploration objectives, trading the viable WRS configurations identified in Phase I to identify the ideal exploration WRS. The results of Phases I and II are discussed in this paper.