2005 IEEE Aerospace Conference最新文献

{"title":"The AFRL/STP Nanosat-2 Mission on Delta IV Heavy: A Demonstration of Current Responsive Space Capabilities","authors":"G. Hunyadi, J. Ganley, L. Berenberg, E. Henrikson","doi":"10.1109/AERO.2005.1559582","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559582","url":null,"abstract":"In mid CY2003, the Air Force Space and Missile Systems Center commander (SMC/CC) tasked the Department of Defense Space Test Program (STP) with finding a payload that could be manifested on the Air Force Delta IV Heavy Launch Vehicle Demonstration (HLVD), which was originally scheduled for a May 2004 Initial Launch Capability (ILC). In late CY2003, the decision was made to pursue the Air Force Research Laboratory (AFRL) Nanosat-2/Three Corner Sat (NS2/3CS) satellite constellation. In January 2004, SMC/CC provided the direction to proceed with the Nanosat-2 integration effort. Fortunately, the new HLVD ILC had moved to 3 July 2004. This situation created the ultimate exercise in \"responsive space\": notice-to-proceed to space vehicle delivery for integration in less than three months. A subsequent launch delay to September 2004 approximately halfway through the effort did not significantly relieve the schedule pressure, due to increased requirements being levied on the payload. Originally designed for deployment from the Space Shuttle (STS), the NS2/3CS payload consisted of the three university-built satellites comprising the 3CS constellation, and an AFRL-developed Multi-Satellite Deployment System (MSDS) incorporating novel low-shock separation systems developed under contract to AFRL by Planetary Systems Corp. (PSC) and Starsys Research Corp. (SRC). With the transition to Delta IV, new launch vehicle environments and requirements forced a radical and rapid reconfiguration of the Nanosat-2 mission from the ground up. The Delta IV Heavy first flight was a demonstration mission orbiting an inert \"Demosat\", and the NS2/3CS hardware was modified to piggyback on the Demosat until the MSDS released the 3CS constellation into low earth orbit. The ground rule for manifesting NS2/3CS was zero (minimized) impact on the HLVD mission. All interfaces were optimized for low schedule, performance and budget risk. Due to the transition to HLVD environments and a new target orbit, available mission lifetime fell from months to days, resulting in a limited 3CS mission de-scope. While retaining the core elements of the original NS2/3CS mission architecture, the MSDS deployment topology was reworked to meet Delta IV mechanical and electrical interface requirements, the number of satellites in the 3CS constellation was reduced from three to two, and mission operations were streamlined and accelerated. From start-work, system reconfiguration was accomplished in only 36 days, and qualification tests and analyses were subsequently completed over the ten week period leading up to encapsulation. The entire AFRL/STP effort was performed with a critical mission team numbering only in the low tens. As one of the more responsive missions attempted to date, the NS2/3CS mission provided valuable insight into the viability of highly accelerated and non-traditional assembly, integration & test (AI&T) practices. Using the NS2/3CS experience as a baseline, this paper outlines the e","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122197164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Managed learning for engineers/scientists in a corporate university setting","authors":"J. Gregg","doi":"10.1109/AERO.2005.1559752","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559752","url":null,"abstract":"Corporate education in engineering firms is valued with varying degree depending on the nature of the economic sector, the climate of the firm, and the perspective of the leadership team. Organizations must cope with new customer demands, shifting employment pools, cyclical economic pressures, and their own internal needs to acquire the technical competencies to capture new business and deliver on contractual promises. Furthermore, the relentless advancement of the engineering practice has caused practitioners to grow increasingly out of synch with their earlier college education, which has created a serious education gap in firms with aging professional workforces. The corporate university offers aerospace and engineering firms an opportunity to align learning resources to strategic objectives by centralizing corporate education. The vision of the corporate university is to fill current need and to plan for future critical skill development in three content areas. These are critical skills development, leadership and management development and professional development. The scope of these content areas is integrative and overlapping. The paper posits why training is necessary to the strategic success of large aerospace firms, discusses the background of corporate universities in the international arena, presents a universally accepted comparison between the traditional view of decentralized training departments and the centralized corporate university perspective, outlines a working learning content model that encompasses a multi-tier approach, suggests critical activities for the startup, development and maintenance of the corporate university, and ends with a high level two-phase approach for creating and launching a corporate university","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"2017 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116999900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Detection and Classification of Broadband Signals in Reverberant Dispersive Environments","authors":"R. Lynch, I. Kirsteins, J. Kelly","doi":"10.1109/AERO.2005.1559532","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559532","url":null,"abstract":"The use of broadband waveforms has been suggested as a means of improving active sonar performance against slow moving or stationary targets in littoral waters. In principle, the use of a wide spectrum permits the design of waveforms with nearly ideal \"thumbtack-like\" ambiguity functions. However, the ocean has dispersive characteristics in both time and frequency that can prevent the idealized broadband gains from being realized. These dispersive effects or coherence losses result in nonidealized signal-echo cross-ambiguity function properties. At present, it is not well understood how coherence losses affect the cross-ambiguity function. The objectives of this paper are to investigate the study and quantify the effects of coherence loss on detection in reverberation-limited environments and provide insight into the maximum tolerable coherence losses and optimum sonar receiver design","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129508254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Array deformation performance impacts on a LEO L-band GMTI SBR","authors":"P. Zulch, R. Hancock, J. Mckay","doi":"10.1109/AERO.2005.1559509","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559509","url":null,"abstract":"Space based radar (SBR) has been investigated for decades and has once again made an appearance as a viable method for performing the moving target indication (MTI) mission. Large arrays are needed for this application in order to provide adequate energy on target for detection and to minimize the observed ground clutter Doppler spread. Large phased arrays in space are likely to experience mechanical deformation both at the sub-array panel level and across the structure as a whole. The impact of antenna deformations on antenna pattern, peak directive gain, and signal to interference plus noise ratio loss (SINRL), which shows impact on minimum discernable velocity (MDV), is demonstrated. This paper address the deformations when applied to a low earth orbit (LEO) based L-band radar concept of interest to the US Air Force (USAF) and NASA","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129834193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Knowledge representation standards and interchange formats for causal graphs","authors":"D. Throop, Jane T. Malin, L. Fleming","doi":"10.1109/AERO.2005.1559747","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559747","url":null,"abstract":"In many domains, automated reasoning tools must represent graphs of causally linked events. These include fault-tree analysis, probabilistic risk assessment (PRA), planning, and procedures, medical reasoning about disease progression, and functional architectures. Each field has its own requirements for the representation of causation, events, actors and conditions. In no domain has a generally accepted interchange format emerged. This paper makes progress towards interoperability across the wide range of causal analysis methodologies. We survey existing practice and emerging interchange formats across these fields. Setting forth a set of terms and concepts that are broadly shared across the domains, we examine the several ways in which current practice represents them. Some phenomena are difficult to represent or to analyze in several domains. These include mode transitions, reachability analysis, positive and negative feedback loops, conditions correlated but not causally linked and bimodal probability distributions. We work through examples and contrast the differing methods for addressing them. We detail recent work in knowledge interchange formats for causal trees in aerospace analysis applications in early design, safety and reliability. Several examples are discussed, with a particular focus on reachability analysis and mode transitions. We generalize the aerospace analysis work across the several other domains. We also recommend features and capabilities for the next generation of causal knowledge representation standards","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128451307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive Clustering Protocol for Sensor Networks","authors":"A. Durresi, V. Paruchuri","doi":"10.1109/AERO.2005.1559522","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559522","url":null,"abstract":"In this paper, we present adaptive clustering protocol (ACP) for sensor networks. Clustering techniques are used by different protocols and applications to increase scalability and reduce delays in sensor networks. Examples include routing protocols, and applications requiring efficient data aggregation. Our approach which is based on The Covering Problem that aims at covering an area with minimum possible circular disks assuming ideal conditions. ACP is a lightweight protocol that does not require any neighborhood information and imposes lesser communication overhead. We present simulation results to show the efficiency of ACP in both ideal cases and randomly distributed networks. Moreover, ACP is scalable with respect to density and network size","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128667573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-dimensional, nonlinear oscillator array antenna","authors":"T. Heath, R. Kerr, G. Hopkins","doi":"10.1109/AERO.2005.1559401","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559401","url":null,"abstract":"This paper details the design and performance of a 25-element, two-dimensional, nonlinear oscillator array antenna operating near the L1 GPS (1.57542 GHz) frequency. A simple theoretical framework for understanding its principle of operation (a reliance on the synchronization properties of coupled, nonlinear oscillators for phase coherence and inertia-less scanning) is provided. A unique feature of this design, the integration of diagnostic circuitry for the real-time simultaneous measurement of element-level amplitude and phase for calibration and control, is described.","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"5 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129254895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assured Counter-Terrorism Information Sharing Using Attribute Based Information Security (ABIS)","authors":"E. Yuan, G. Wenzel","doi":"10.1109/AERO.2005.1559621","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559621","url":null,"abstract":"For counter-terrorism information sharing, just like for many other government and military operations in the post-9/11 world, the traditional mindset of \"need to know\" is being overtaken by the \"need to share\" among dynamic communities of interests (COIs). The problem with current IT environments and security mechanisms forces equal sharing of all information at the lowest common denominator, often requiring setting up new physical networks to protect the information boundaries, which is often time-consuming, costly, and not interoperable. The recent technology evolution towards service oriented architectures (SOAs) helps establish a loosely coupled, interoperable \"system of systems\" platform, however they also bring about their own security challenges. This paper outlines the inefficiency of conventional network boundary based, protection-oriented information security mechanisms as well as the new security challenges for the emerging SOA technologies, and proposes attribute based information security (ABIS) as a new approach for addressing these challenges. Center to this new approach is a generic attribute based access control (ABAC) model, which is based on subject, object, and environment attributes and supports both mandatory and discretionary access control needs. To realize the potentials of the ABAC model, the paper introduces a high level ABIS reference architecture, which reflects the proposed technical approaches to achieve an attribute-centric security methodology: First of all, to establish such an environment that facilitates the seamless flow of information between collaborating parties, the capability to provision and manage attributes for subjects and resources needs to be established. Secondly, attribute-binding mechanisms need to be in place to support the integrity and data assurance of the information objects. Next, the architecture should provide identification, authentication and authorization mechanisms based on the attributes. Building upon these tasks will lead to the establishment of \"trusted information domains\" within a shared network infrastructure, providing the ability to establish logical COIs seamlessly, created as needed or modified as policy dictates. The paper explores the possibilities of extending the ABAC model to across trust domains, allowing multiple levels of policy enforcement and policy federation","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129272118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Planetary protection technology for Mars Sample Return","authors":"R. Gershman, M. Adams, R. Dillman, J. Fragola","doi":"10.1109/AERO.2005.1559390","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559390","url":null,"abstract":"The NASA Mars Exploration Program has recently adopted a plan that includes a first Mars Sample Return (MSR) mission proposed for launch in 2013. Such a mission would deal with two new categories of planetary protection requirements: (1) assuring a very low probability of inadvertent sample release in order to provide extra protection against the extremely unlikely possibility of biological hazards in the returned material; and (2) keeping the samples free of round-trip Earth organisms to facilitate evaluation after return to Earth. This paper describes the planetary-protection-related technical challenges awaiting any MSR mission and describes work in progress on technology needed to meet these challenges. New technology is needed for several functions. Containment assurance requires breaking the chain of contact with Mars: the exterior of the sample container must not be contaminated with Mars material either during the loading process or during launch from the Mars surface. Also, the sample container and its seals must survive the worst Earth impact corresponding to the candidate mission profile, the Earth return vehicle must provide accurate delivery to the Earth entry corridor, and the Earth entry vehicle must withstand the thermal and structural rigors of Earth atmosphere entry - all with an unprecedented degree of confidence. Sample contamination must be avoided by sterilizing the entire spacecraft, a challenge with modern avionics, or by sterilizing the sample collection and containment gear and then isolating it from other parts of the spacecraft.","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130583981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solar proton dose exposures using low-Z and high-Z materials","authors":"B. Atwell, B. Bartholet, B. Reddell, L. Townsend, T. Miller, J. Edwards, C. Campbell","doi":"10.1109/AERO.2005.1559362","DOIUrl":"https://doi.org/10.1109/AERO.2005.1559362","url":null,"abstract":"Solar particle events (SPEs) represent serious concerns to humans and onboard systems in space. Historically, passive bulk shielding, usually aluminum, has been used to minimize space radiation exposures and subsequent physical and biological effects. In this paper, a review of the major SPEs that have occurred in the last 50 years is presented. Prior to 1976, historical SPE particle spectra were obtained from pre-GOES (geostationary orbiting environmental satellite) spacecraft such as the IMP (interplanetary monitoring platform) -34 and -41 spacecraft. For the time period 1976 to current, the GOES SEM (space environment monitor) SPE particle data were used for several of the larger SPEs in this parametric shielding study. SPE particle spectra were calculated for LEO (low Earth orbit) and for the lunar and Mars environments. Using these particle spectra as input source terms and selected high-energy particle transport codes, both deterministic and Monte Carlo, the results of a parametric shielding study using both low-Z and high-Z materials are discussed. Multiple radiation transport codes were used to inter-compare the results for validation and to present benchmark results for the space community.","PeriodicalId":117223,"journal":{"name":"2005 IEEE Aerospace Conference","volume":"1031 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116260376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}