56 research outputs found

    AEGIS Data Analysis and Reduction (ADAR) in Support of the AEGIS Weapon System (AWS)

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    The AEGIS Weapons System (AWS), part of the AEGIS Combat System (ACS), is an integral part of the defense system on U.S. Navy AEGIS-class ships. AEGIS Data Analysis and Reduction (ADAR) has been developed to assist in the evaluation of the AWS data. ADAR, along with the AWS and ACS, has evolved through the years to accommodate advances in technology and computer programming languages. Additionally, ADAR has evolved so that users located at sites other than the Naval Surface Warfare System Dahlgren Division (NSWCDD), Dahlgren, Virginia, can reduce tactical system data and perform data analysis using the reduced data. This paper is a study of the growing pains experienced by the ADAR system as it has evolved. Some of the changes affecting ADAR have included the addition of new elements to both the AWS and the ACS, the multiplication of AEGIS baselines, and the provision of portability both to a multitude of platforms and to several sites supporting the AEGIS program

    Energy Issues under Deregulated Environment

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    Cyber-Based Contingency Analysis and Insurance Implications of Power Grid

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    Cybersecurity for power communication infrastructure is a serious subject that has been discussed for a decade since the first North American Electric Reliability Corporation (NERC) critical infrastructure protection (CIP) initiative in 2006. Its credibility on plausibility has been evidenced by attack events in the recent past. Although this is a very high impact, rare probability event, the establishment of quantitative measures would help asset owners in making a series of investment decisions. First, this dissertation tackles attackers\u27 strategies based on the current communication architecture between remote IP-based (unmanned) power substations and energy control centers. Hypothetically, the identification of intrusion paths will lead to the worst-case scenarios that the attackers could do harm to the grid, e.g., how this switching attack may perturb to future cascading outages within a control area when an IP-based substation is compromised. Systematic approaches are proposed in this dissertation on how to systematically determine pivotal substations and how investment can be prioritized to maintain and appropriate a reasonable investment in protecting their existing cyberinfrastructure. More specifically, the second essay of this dissertation focuses on digital protecting relaying, which could have similar detrimental effects on the overall grid\u27s stability. The R-k contingency analyses are proposed to verify with steady-state and dynamic simulations to ensure consistencies of simulation outcome in the proposed modeling in a power system. This is under the assumption that attackers are able to enumerate all electronic devices and computers within a compromised substation network. The essay also assists stakeholders (the defenders) in planning out exhaustively to identify the critical digital relays to be deployed in substations. The systematic methods are the combinatorial evaluation to incorporate the simulated statistics in the proposed metrics that are used based on the physics and simulation studies using existing power system tools. Finally, a risk transfer mechanism of cyber insurance against disruptive switching attacks is studied comprehensively based on the aforementioned two attackers\u27 tactics. The evaluation hypothetically assesses the occurrence of anomalies and how these footprints of attackers can lead to a potential cascading blackout as well as to restore the power back to normal stage. The research proposes a framework of cyber insurance premium calculation based on the ruin probability theory, by modeling potential electronic intrusion and its direct impacts. This preliminary actuarial model can further improve the security of the protective parameters of the critical infrastructure via incentivizing investment in security technologies

    Advanced wind energy convertors using electronic power conversion.

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    SIGLEAvailable from British Library Document Supply Centre-DSC:DXN013000 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    A kinematic numerical camera model for the SPOT-1 sensor

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    A novel method for modelling linear push-broom sensors has been developed. A numerical model which incorporates the satellite attitude and position data is used to compute the absolute orientation. This method makes a break with traditional photogrammetric practice, in that instead of using an approach based on collinearity equations, the absolute orientation is computed iteratively using a numerical multi-variable minimisation scheme. All current implementations of the model use the Powell direction-set method, but in principle, any multivariable minimisation scheme could be substituted. The numerical method has significant advantages over the collinearity approach. The number of ground control points needed to form an accurate model is reduced and the numerical approach offers a superior basis for the development of general purpose multi sensor modelling software. In order to test these assertions, a numerical model of the SPOT-1 sensor was coded and tested against a pre-existing collinearity based model. Exhaustive tests showed the numerical model, using 3 or fewer ground control points, consistendy equaled or bettered the performance of the earlier model, using between 6 and 15 ground control points, on the same test data. A general purpose sensor modelling system was developed using the code developed for the initial SPOT-1 model. Currently this system supports many rigid linear sensors systems including SPOT-1, SPOT-2, FTIR, MISR, MEOSS and ASAS. Further extensions to the system to enable it to model non-rigid linear sensors such as AVHRR and ATM are planned. Work to enable the system to perform relative orientations for a variety of sensor types is also ongoing

    Authorisation Issues for Mobile Code in Mobile Systems

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    This thesis is concerned with authorisation issues for mobile code in mobile systems. It is divided into three main parts. Part I covers the development of a policy-based framework for the authorisation of mobile code and agents by host systems. Part II addresses the secure download, storage and execution of a conditional access application, used in the secure distribution of digital video broadcast content. Part III explores the way in which trusted computing technology may be used in the robust implementation of OMA DRM version 2. In part I of this thesis, we construct a policy-based mobile code and agent authorisation framework, with the objective of providing both mobile devices and service providers with the ability to assign appropriate privileges to incoming executables. Whilst mobile code and agent authorisation mechanisms have previously been considered in a general context, this thesis focuses on the special requirements resulting from mobile code and agent authorisation in a mobile environment, which restrict the types of solutions that may be viable. Following the description and analysis of a number of architectural models upon which a policy-based framework for mobile code and agent authorisation may be constructed, we outline a list of features desirable in the definitive underlying architecture. Specific implementation requirements for the capabilities of the policy and attribute certificate specification languages and the associated policy engine are then extracted. Candidate policy specification languages, namely KeyNote (and Nereus), Ponder (and (D)TPL) and SAML are then examined, and conclusions drawn regarding their suitability for framework expression. Finally, the definitive policy based framework for mobile code and agent authorisation is described. In the second part of this thesis, a flexible approach that allows consumer products to support a wide range of proprietary content protection systems, or more specifically digital video broadcast conditional access systems, is proposed. Two protocols for the secure download of content protection software to mobile devices are described. The protocols apply concepts from trusted computing to demonstrate that a platform is in a sufficiently trustworthy state before any application or associated keys are securely downloaded. The protocols are designed to allow mobile devices to receive broadcast content protected by proprietary conditional access applications. Generic protocols are first described, followed by an analysis of how well the downloaded code is protected in transmission. How the generic protocols may be implemented using specific trusted computing technologies is then investigated. For each of the selected trusted computing technologies, an analysis of how the conditional access application is protected while in storage and while executing on the mobile host is also presented. We then examine two previously proposed download protocols, which assume a mobile receiver compliant with the XOM and AEGIS system architectures. Both protocols are then analysed against the security requirements defined for secure application download, storage and execution. We subsequently give a series of proposed enhancements to the protocols which are designed to address the identified shortcomings. In the final section of this thesis, we examine OMA DRM version 2, which defines the messages, protocols and mechanisms necessary in order to control the use of digital content in a mobile environment. However, an organisation, such as the CMLA, must specify how robust implementations of the OMA DRM version 2 specification should be, so that content providers can be confident that their content will be safe on OMA DRM version 2 devices. We take the requirements extracted for the robust implementation of the OMA DRM version 2 specification and propose an implementation which meets these requirements using the TCG architecture and TPM/TSS version 1.2 commands

    Modes of Interaction in Computational Architecture

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    This thesis is an enquiry into the importance and influence of interaction in architecture, the importance of which is observed through different modes of interaction occurring in various aspects of architectural discourse and practice. Interaction is primarily observed through the different use of software within architectural practice and in the construction of buildings, façades and systems. In turn, the kind of influences software has on architecture is one of the underlying questions of this thesis. Four qualities: Concept, Materiality, Digitization and Interactivity, are proposed as a theoretical base for the analysis and assessment of different aspects of computational architecture. These four qualities permeate and connect the diverse areas of research discussed, including architecture, cybernetics, computer science, interaction design and new media studies, which in combination provide the theoretical background. The modalities of computational architecture analysed here are, digital interior spaces, digitized design processes and communicational exterior environments. The analysis is conducted through case studies: The Fun Palace, Generator Project, Water Pavilion, Tower of Winds, Institute du Monde Arabe, The KPN building, Aegis Hyposurface, BIX Façade, Galleria Department Store, Dexia Tower, and also E:cue, Microstation, Auto-Cad, Rhino, Top Solid and GenerativeComponents software. These are important for discussion because they present different architectural concepts and thoughts about interactivity within architecture. The analytical processes used in the research distinguished and refined, eight modes of interaction: (1) interaction as a participatory process; (2) cybernetic mutualism; (3) thematic interaction; (4) human-computer interaction during architectural design production; (5) interaction during digital fabrication; (6) parametric interaction; (7) kinetic interaction with dynamic architectural forms; and (8) interaction with façades. Out of these, cybernetic mutualism is the mode of interaction proposed by this thesis
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