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TAPAT computer program for design and analysis of radiation shields in nuclear rocketry
The Modern2020 project aims at providing the means for developing and implementing an effective and efficient repository operational monitoring program, taking into account the requirements of specific national programs. The work allows advanced national radioactive waste disposal programs to design monitoring systems suitable for deployment when repositories start operating in the next decade and supports less developed programs and other stakeholders by illustrating how the national context can be taken into account in designing dedicated monitoring programs tailored to their national needs. The work has been established to understand what should be monitored within the frame of the wider safety cases and to provide methodology on how monitoring information can be used to support decision-making and to plan for responding to monitoring results. Several developments on innovative repository monitoring techniques (wireless data transmission, alternative power supply sources, new sensors, geophysical methods) has been done from the proof of feasibility stage to the technology development and demonstration phase. Innovative technical solutions facilitate the integration and flexibility of required monitoring components to ease the final implementation and adaptation of the monitoring system. Full-scale in-situ demonstrations of innovative monitoring techniques were done in way to evaluate the performance of the state-of-the-art, the innovative techniques and their comparison with conventional ones. Finally, we will introduce the experiences of the local public stakeholders that have been involved in the Modern2020 project by focusing on the participation in practice of the Belgian, French, Finnish and Swedish local stakeholders, This paper provides an overview of the European Commission Horizon2020 Modern2020 project's main goals and progress to date. (authors)
The natural environment design criteria requirements for use in the Space Station and its Elements (SSPE) definition phase studies are presented. The atmospheric dynamic and thermodynamic environments, meteoroids, radiation, physical constants are addressed. It is intended to enable all groups involved in the definition phase studies to proceed with a common and consistent set of natural environment criteria requirements.
Purpose: The Australian Clinical Dosimetry Service, (ACDS) was a pilot program to enable the Australian Government to determine whether a locally designed audit program was suitable for mitigating dosimetric error risk to radiotherapy patients within Australia. The outcomes from four years of operations will be presented and discussed with a focus why and how the pilot requirements were met. The consequnces of success will be considered, the lessons learnt from the pilot program and how they are impacting the future ACDS design, operation and engagement with stakeholders. Methods: The ACDS was designed over 2010/11 by experts drawn from the three professions in consultation with the national Department of Health. The list of outcomes required over a three year pilot was expressed in a Memorandum of Understanding, (MoU) between Health and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) which hosted the ACDS. Results: The ACDS has achieved all the MoU requirements. This paper describes how the staff within the ACDS engaged with the professional clinical workforce and provided a successful and functioning audit service. It identifies the strengths and weaknesses within the MoU and the ACDS structure and how the ACDS resolved a number of conflicting issues. It identifies the successes within the ACDS and how these were achieved. It provides details to assist and advise those seeking to design or modify national or regional auditing programs. Finally the paper reviews potential futures for the ACDS. Conclusion: The raw number of audits and outcomes indicate that the ACDS has met the MoU auditing requirements. The reasons for the ACDS’ success are highly dependent on: attracting quality staff who can respond with agility to changing situations, a high level of communication with the professional community, a high level of engagement by the community and an interested and engaged Federal Department. The Australian Clinical Dosimetry Service is a joint initiative between the Australian Department of Health and the Australian Radiation Protection and Nuclear Safety Agency.
Space Station Freedom is designed to be an Earth-orbiting multidiscipline research and development (R&D) facility capable of evolution to accommodate a variety of potential uses. One evolution scenario is growth to an enhanced R&D facility. In support of the Space Station Freedom Program Preliminary Design Review, the NASA Langley Research Center Space Station Office is analyzing growth requirements and evaluating configurations for this R&D utilization. This paper presents a summary of this analysis including time-phased growth plans, R&D growth issues and configurations, and recommendations for the program baseline design which will facilitate evolutionary R&D growth.
Space Station Freedom is designed to be an Earth-orbiting, multidiscipline research and development (R&D) facility capable of evolution to accomodate a variety of potential uses. One evolution scenario is growth to an enhanced R&D facility. In support of the Space Station Freedom Program Preliminary Design Review (PDR), the NASA Langley Research Center Space Station Office is analyzing growth requirements and evaluating configurations for this R&D utilization. This paper presents a summary of FY1989 study results including time-phased growth plans, R&D growth issues and configurations, and recommendations for the program baseline design which will facilitate evolutionary R&D growth. This study consisted of three major areas of concentration: mission requirements analysis; Space Station Freedom systems growth analysis; and growth accomodations and trades. Mission requirements analysis was performed to develop a realistic mission model of post-Phase 1 R&D missions. A systems-level analysis was performed to project incremental growth requirements of Space Station Freedom needed to support these R&D missions. Identification of growth requirements and specific growth elements led to the need for special accomodations analyses and trades. These studies included identification of hooks and scars on the baseline design, determination of an optimal module growth pattern, analysis of the dual keel length, and determination of an optimal locaton for the customer servicing facility. Results of this study show that Space Station Freedom must be capable of evolving to a dual keel, eight pressurized module configuration (two growth habs and two growth labs); providing 275 kW power (for experimenters and station housekeeping); accomodating a crew of 24; and supporting other growth structures and special facilities to meet projected R&D mission requirements.
A program to design, fabricate and test a dimensionally stable metering structure in support of the large space telescope (LST) program is discussed. Graphite/epoxy was the material selected as the only viable candidate material which can meet the stringent thermal expansion criteria of the LST. A metering shell was designed and fabricated, with emphasis on dimensional stability in conjunction with low cost. Thermal expansion test coupons extracted from the layups of the skin panels indicated the attainment of a coefficient of thermal expansion of 0.0666 micrometers/m K. Subsequent thermal vacuum chamber tests on the complete metering shell demonstrated an expansion of the 2.95-meter overall length of 0.27 micrometers/K. Static and dynamics tests, which demonstrated adequacy with respect to limit loads and stiffness, were also accomplished.
Executive Control Systems (ECSs) are software structures for the unification of various engineering design application programs into comprehensive systems with a central user interface (uniform access) method and a data management facility. Attention is presently given to the most significant determinations of a research program conducted for 24 ECSs, used in government and industry engineering design environments to integrate CAD/CAE applications programs. Characterizations are given for the systems' major architectural components and the alternative design approaches considered in their development. Attention is given to ECS development prospects in the areas of interdisciplinary usage, standardization, knowledge utilization, and computer science technology transfer.
MagBear12 is a computer code that assists in the design of radial, heteropolar active magnetic bearings (AMBs). MagBear12 was developed to help in designing the system described in "Advanced Active-Magnetic-Bearing Thrust-Measurement System". Beyond this initial application, MagBear12 is expected to be useful for designing AMBs for a variety of rotating machinery. This program incorporates design rules and governing equations that are also implemented in other, proprietary design software used by AMB manufacturers. In addition, this program incorporates an advanced unpublished fringing-magnetic-field model that increases accuracy beyond that offered by the other AMB-design software.
A computer program helps to blend the power of automated-search software, which is able to generate large numbers of design solutions, with the insight of expert designers, who are able to identify preferred designs but do not have time to examine all the solutions. From among the many automated solutions to a given design problem, the program selects a smaller number of solutions that are worthy of scrutiny by the experts in the sense that they are sufficiently dissimilar from each other. The program makes the selection in an interactive process that involves a sequence of data-mining steps interspersed with visual displays of results of these steps to the experts. At crucial points between steps, the experts provide directives to guide the process. The program uses heuristic search techniques to identify nearly optimal design solutions and uses dissimilarity metrics defined by the experts to characterize the degree to which solutions are interestingly different. The search, data-mining, and visualization features of the program were derived from previously developed risk-management software used to support a risk-centric design methodology
The appendices A-K to the user's manual for the rocket combustor interactive design (ROCCID) computer program are presented. This includes installation instructions, flow charts, subroutine model documentation, and sample output files. The ROCCID program, written in Fortran 77, provides a standardized methodology using state of the art codes and procedures for the analysis of a liquid rocket engine combustor's steady state combustion performance and combustion stability. The ROCCID is currently capable of analyzing mixed element injector patterns containing impinging like doublet or unlike triplet, showerhead, shear coaxial and swirl coaxial elements as long as only one element type exists in each injector core, baffle, or barrier zone. Real propellant properties of oxygen, hydrogen, methane, propane, and RP-1 are included in ROCCID. The properties of other propellants can be easily added. The analysis models in ROCCID can account for the influences of acoustic cavities, helmholtz resonators, and radial thrust chamber baffles on combustion stability. ROCCID also contains the logic to interactively create a combustor design which meets input performance and stability goals. A preliminary design results from the application of historical correlations to the input design requirements. The steady state performance and combustion stability of this design is evaluated using the analysis models, and ROCCID guides the user as to the design changes required to satisfy the user's performance and stability goals, including the design of stability aids. Output from ROCCID includes a formatted input file for the standardized JANNAF engine performance prediction procedure.
NASA's Commercial Crew Development Program is designed to stimulate efforts within the private sector that will aid in the development and demonstration of safe, reliable, and cost-effective space transportation capabilities. With the goal of delivery cargo and eventually crew to Low Earth Orbit (LEO) and the International Space Station (ISS) the program is designed to foster the development of new spacecraft and launch vehicles in the commercial sector. Through Space Act Agreements (SAAs) in 2011 NASA provided $50M of funding to four partners; Blue Origin, The Boeing Company, Sierra Nevada Corporation, and SpaceX. Additional, NASA has signed two unfunded SAAs with ATK and United Space Alliance. This paper will give a brief summary of these SAAs. Additionally, a brief overview will be provided of the released version of the Commercial Crew Development Program plans and requirements documents.
Computer weight/performance prediction method to assess design and program and to optimize structural systems similar to those of Saturn V for management planning
An important element of the internationally structured Global Precipitation Measurement (GPM) mission will be its ground validation research program. Within the last year, the initial architecture of this program has taken shape. This talk will describe that architecture, both in terms of the international program and in terms of the separate regional programs of the principle participating space agencies, i.e., ESA, JAXA, and NASA. There are three overriding goals being addressed in the planning of this program; (1) establishing various new, challenging and important scientific research goals vis-a-vis current ground validation programs supporting satellite retrieval of precipitation; (2) designing the program as an international partnership which operates, out of necessity, heterogeneous sites in terms of their respective observational foci and science thrusts, but anneals itself in terms of achieving a few overarching scientific objectives; and (3) developing a well-designed protocol that allows specific sites or site networks, at their choosing, to operate in a 'supersite' mode - defined as the capability to routinely transmit GV information at low latency to GPM's Precipitation Processing System (PPS). (The PPS is being designed as GPM's data information system, a distributed data system with main centers at the Goddard Space Flight Center (GSFC) within NASA, the Earth Observation Research Center (EORC) within JAXA, and a TBD facility to be identified by the ESA s ESTEC facility in Noordwijk.)
The LUMIS program has designed an integrated geographic information system to assist program managers and planning groups in metropolitan regions. Described is the system designed to interactively interrogate a data base, display graphically a portion of the region enclosed in the data base, and perform cross tabulations of variables within each city block, block group, or census tract. The system is designed to interface with U. S. Census DIME file technology, but can accept alternative districting conventions. The system is described on three levels: (1) introduction to the systems's concept and potential applications; (2) the method of operating the system on an interactive terminal; and (3) a detailed system specification for computer facility personnel.
A handbook is presented which delineates the principles of the new low-cost design methodology for designers of unmanned payloads to be carried by the space shuttle. The basic relationships between payload designs and program cost effects are discussed, and some concepts for designing low-cost payloads and implementing low-cost programs are given. The data are summarized from a payloads effects study of three unmanned earth satellites (OAO, a syneq orbiter, and a small research satellite), and the earth satellite design is emphasized. Brief summaries of space shuttle and space tug performance, environmental, and interface data pertinent to low-cost payload concepts are included.
Design modifications, proof test, and delivery program of igniters for Recruit rocket engines
Purpose: To design and implement a unique training program that uses a phantom-based simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education. Methods and Materials: Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 ({sup 125}I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis. Results: Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 >95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees' ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process. Conclusions: Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB.