Adaptive image segmentation using genetic and hybrid search methods

This paper describes an adaptive approach for the important image processing problem of image segmentation that relies on learning from experience to adapt and improve the segmentation performance. The adaptive image segmentation system incorporates a feedback loop consisting of a machine learning subsystem, an image segmentation algorithm, and an evaluation component which determines segmentation quality. The machine learning component is based on genetic adaptation and uses (separately) a pure genetic algorithm (GA) and a hybrid of GA and hill climbing (HC). When the learning subsystem is based on pure genetics, the corresponding evaluation component is based on a vector of evaluation criteria. For the hybrid case, the system employs a scalar evaluation measure which is a weighted combination of the different criteria. Experimental results for pure genetic and hybrid search methods are presented using a representative database of outdoor TV imagery. The multiobjective optimization demonstrates the ability of the adaptive image segmentation system to provide high quality segmentation results in a minimal number of generations     

Electronic flight progress strip prototype for en route ATC

An electronic flight progress strip (FPS) display and a color plan view display (CPVD) as a laboratory prototype are described. The purposes of prototype development are to examine the effectiveness and problems of the electronic FPS display in comparison to the current system and to identify the controller-workstation requirements, which are necessary to decide a future planning of a production prototype development. The evaluation and additional test were conducted for a typical en route transition sector. It was found that electronic FPS was useful in the normal traffic load. Some possible improvements were identified in the heavy traffic load situations represented in the additional test     

Principal components, covariance matrix tapers, and the subspaceleakage problem

A new class of robust space-time adaptive beamforming techniques is introduced to address a broad range of subspace leakage phenomena that arise in many sensor array applications. When present, these leakage phenomena can significantly increase the effective rank of the dominant colored noise interference spectrum, thereby reducing the appeal of techniques that exploit low-rank dominant interference (such as principal components (PC) or diagonal loading) to reduce sample support (training) requirements. By combining the covariance matrix taper (CMT) approach with either PC or diagonal loading, the minimal sample support properties of these techniques can be preserved     

3D Coronal structures and their evolutions measured by Stereoscopy,consequences for Space Weather and the STEREO mission

We are discussing methods of stereoscopic 3D reconstruction of coronal loops structures. In our most sophisticated method we fit loops observed with SOHO/EIT to a set of shape parameters including the internal twist of the loops field lines. We define this twist as the number of turns of the field line around a torus axis between the footpoints of the loops. Twist numbers of the order 0–2 are observed. We observe the emergence of an Active Region with twisted loops which detwist as they expand. The same correlation between detwisting and expansion is observed with filaments in relation to CME formations. On longer time scale, loops seem to accumulate twist, perhaps due to differential rotation. Rapid losses of twist temporarily correlate with flares. From our analysis, we expect that the internal twist of coronal structures will play an important role for the space weather forecast. This revised version was published online in August 2006 with corrections to the Cover Date.     

Conditions of the Maximum Principle in the Problem of Optimal Control over an Aggregate of Dynamic Systems and Their Application to Solution of the Problems of Optimal Control of Spacecraft Motion

The necessary first-order conditions of strong local optimality (conditions of maximum principle) are considered for the problems of optimal control over a set of dynamic systems. To derive them a method is suggested based on the Lagrange principle of removing constraints in the problems on a conditional extremum in a functional space. An algorithm of conversion from the problem of optimal control of an aggregate of dynamic systems to a multipoint boundary value problem is suggested for a set of systems of ordinary differential equations with the complete set of conditions necessary for its solution. An example of application of the methods and algorithm proposed is considered: the solution of the problem of constructing the trajectories of a spacecraft flight at a constant altitude above a preset area (or above a preset point) of a planet's surface in a vacuum (for a planet with atmosphere beyond the atmosphere). The spacecraft is launched from a certain circular orbit of a planet's satellite. This orbit is to be determined (optimized). Then the satellite is injected to the desired trajectory segment (or desired point) of a flyby above the planet's surface at a specified altitude. After the flyby the satellite is returned to the initial circular orbit. A method is proposed of correct accounting for constraints imposed on overload (mixed restrictions of inequality type) and on the distance from the planet center: extended (nonpointlike) intermediate (phase) restrictions of the equality type.     

Mechanism for assembling antenna in space

The development of large and precise space antennas is one of the most important topics in constructing space infrastructures. We evaluated an approach to assembling large and accurate space antennas which uses space robots. The assembly mechanism was launched together with the ETS-VII, the first telerobotic satellite from Japan, and its performance, including fully automatic assembling, was verified. The assembling-type antenna and the results of antenna assembly experiments are discussed     

The Earth's Magnetosphere Response to Solar Wind Events according to the INTERBALL Project Data

The results of studying the interaction of two types of the solar wind (magnetic clouds and solar wind of extremely low density) with the Earth's magnetosphere are discussed. This study is based of the INTERBALL space project measurements and on the other ground-based and space observations. For moderate variations of the solar wind and interplanetary magnetic field (IMF) parameters, the response of the magnetosphere is similar to its response to similar changes in the absence of magnetic clouds and depends on a previous history of IMF variations. Extremely large density variations on the interplanetary shocks, and on leading and trailing edges of the clouds result in a strong deformation of the magnetosphere, in large-scale motion of the geomagnetic tail, and in the development of magnetic substorms and storms. The important consequences of these processes are: (1) the observation of regions of the magnetosphere and its boundaries at great distances from the average location; (2) density and temperature variations in the outer regions of the magnetosphere; (3) multiple crossings of geomagnetic tail boundaries by a satellite; and (4) bursty fluxes of electrons and ions in the magnetotail, auroral region, and the polar cap. Several polar activations and substorms can develop during a single magnetic cloud arrival; a greater number of these events are accompanied, as a rule, by the development of a stronger magnetic storm. A gradual, but very strong, decrease of the solar wind density on May 10–12, 1999, did not cause noticeable change of geomagnetic indices, though it resulted in considerable expansion of the magnetosphere.     

Radiation biodosimetry: applications for spaceflight.

The multiparametric dosimetry system that we are developing for medical radiological defense applications could be adapted for spaceflight environments. The system complements the internationally accepted personnel dosimeters and cytogenetic analysis of chromosome aberrations, considered the best means of documenting radiation doses for health records. Our system consists of a portable hematology analyzer, molecular biodosimetry using nucleic acid and antigen-based diagnostic equipment, and a dose assessment management software application. A dry-capillary tube reagent-based centrifuge blood cell counter (QBC Autoread Plus, Becton [correction of Beckon] Dickinson Bioscience) measures peripheral blood lymphocytes and monocytes, which could determine radiation dose based on the kinetics of blood cell depletion. Molecular biomarkers for ionizing radiation exposure (gene expression changes, blood proteins) can be measured in real time using such diagnostic detection technologies as miniaturized nucleic acid sequences and antigen-based biosensors, but they require validation of dose-dependent targets and development of optimized protocols and analysis systems. The Biodosimetry Assessment Tool, a software application, calculates radiation dose based on a patient's physical signs and symptoms and blood cell count analysis. It also annotates location of personnel dosimeters, displays a summary of a patient's dosimetric information to healthcare professionals, and archives the data for further use. These radiation assessment diagnostic technologies can have dual-use applications supporting general medical-related care.     

Planetarium Inversum -- a space vision for Earth education.

In a planetarium, the visitor is sitting on Earth and looking into an imaginary space. The Planetarium Inversum is the opposite: visitors are sitting in a space station, looking down on Mother Earth. It is a scientifically-based information show with visitors involvement, its elements being partially virtual (Earth in space has to be projected with highest possible resolution) but also containing real structures, such as the visitors' Earth observatory with adjacent biological systems (plant cultures and other ecological life support components). Its main message concerns the limits and the vulnerability of our home planet, its uniqueness, beauty and above all, its irreplaceableness: Earth does not have an emergency exit. The Earth observatory is part of a ring shaped, rotating space station of the type designed by Wernher von Braun decades ago. Visitors are told that gravity is being substituted by centrifugal force. Both types of life support systems are being demonstrated--self regenerative life based ones and technical ones as a backup (solar electric splitting of water and chemical absorption of respiratory CO2).     

Development of a Digital Array Radar (DAR)

Twenty-first century littoral and open-sea missions present US Navy (USN) shipboard-radar systems with the challenge of detecting small targets in severe clutter and against multiple sources of interference. In Fiscal Year 2000 (FY00), the Office of Naval Research (ONR) sponsored a program to develop an active array radar that includes a digital beamforming (DBF) architecture. The DBF radar system has the potential for improved time-energy management, improved signal-to-clutter (S/C) ratios, improved reliability and reduced life-cycle costs. This paper summarizes the latest developments of the program during FY00