6 research outputs found

    Interpretable Hyperspectral AI: When Non-Convex Modeling meets Hyperspectral Remote Sensing

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    Hyperspectral imaging, also known as image spectrometry, is a landmark technique in geoscience and remote sensing (RS). In the past decade, enormous efforts have been made to process and analyze these hyperspectral (HS) products mainly by means of seasoned experts. However, with the ever-growing volume of data, the bulk of costs in manpower and material resources poses new challenges on reducing the burden of manual labor and improving efficiency. For this reason, it is, therefore, urgent to develop more intelligent and automatic approaches for various HS RS applications. Machine learning (ML) tools with convex optimization have successfully undertaken the tasks of numerous artificial intelligence (AI)-related applications. However, their ability in handling complex practical problems remains limited, particularly for HS data, due to the effects of various spectral variabilities in the process of HS imaging and the complexity and redundancy of higher dimensional HS signals. Compared to the convex models, non-convex modeling, which is capable of characterizing more complex real scenes and providing the model interpretability technically and theoretically, has been proven to be a feasible solution to reduce the gap between challenging HS vision tasks and currently advanced intelligent data processing models

    Grid sensitivity for aerodynamic optimization and flow analysis

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    After reviewing relevant literature, it is apparent that one aspect of aerodynamic sensitivity analysis, namely grid sensitivity, has not been investigated extensively. The grid sensitivity algorithms in most of these studies are based on structural design models. Such models, although sufficient for preliminary or conceptional design, are not acceptable for detailed design analysis. Careless grid sensitivity evaluations, would introduce gradient errors within the sensitivity module, therefore, infecting the overall optimization process. Development of an efficient and reliable grid sensitivity module with special emphasis on aerodynamic applications appear essential. The organization of this study is as follows. The physical and geometric representations of a typical model are derived in chapter 2. The grid generation algorithm and boundary grid distribution are developed in chapter 3. Chapter 4 discusses the theoretical formulation and aerodynamic sensitivity equation. The method of solution is provided in chapter 5. The results are presented and discussed in chapter 6. Finally, some concluding remarks are provided in chapter 7

    Models for optimizing the mix of air launched missiles for repair processing

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    The research for this thesis is concerned with the logistics of air-to-air and air-to-ground missiles. Specific emphasis is placed on the development of models to determine the optimal mix of air launched missiles (ALMs) to induct for repair each quarter at intermediate level maintenance facilities. The Navy operates three such repair facilities. A set of three models are described which are intended to assist in managing the missile repair process. These models allow for effective control of missile readiness objectives, maintenance budgets, and repair priorities. This thesis proposes three linear programming models for the Naval Air Systems Command to use in planning the repair of air-launched missiles through the Naval Weapons Stationshttp://archive.org/details/modelsforoptimiz00taylLieutenant Commander, United States NavyPacific Missile Test Center, Point Mugu, CaliforniaApproved for public release; distribution is unlimited

    Experimental and numerical investigation of shock wave propagation through complex geometry, gas continuous, two-phase media

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    Aeronautical engineering: A cumulative index to a continuing bibliography

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    This bibliography is a cumulative index to the abstracts contained in NASA SP-7037 (197) through NASA SP-7037 (208) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract, report number, and accession number indexes
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