No abstract

It is hard to negate the effects of ocean waves on synthetic aperture sonar that has to be operated in the ocean and many efforts to deal with ocean waves have been made. One of these efforts is motion compensation by calculating phase errors with a computer. But the synthetic aperture algorithm with motion compensation is heavy, and remains difficult to be executed on a real-time basis. Thus, a modified synthetic aperture algorithm is proposed in this paper. This algorithm, which is named a 1.5-dimensional algorithm, is in between a one-dimensional and two-dimensional algorithm. It synthesizes a virtual aperture about 10 times faster than other algorithms in a computer simulation.

Daher ist es möglich, das Signal-zu-Untergrundverhältnis

In application to sonars and underwater transducers a variety of waterless 'solid state' calibration methods can be performed in continuous wave mode (CW). Multi-echo effects arising in such acoustical system are negligibly small due to the large dynamic range of sonar. Sytematic errors can be further eliminated by direct measurements in water. Having test probe scanned or comprised of 1-3 composite it is possible to 'photoprint' aperture function of multi-element, electrically shaded transducers to evaluate cross-coupling and predict sonar performance in the far field.The plates are in acoustical contact with the small probe of the diameter p < < L through the layer of liquid. Thickness of the layer is h. The probe E s positioned over the radiating surfaces by the vector r={x,hp}, where hp=Const..

Expert panels comprised of subject matter experts identified at the U.S. National Laboratories (SNL, ANL, INL, ORNL, LBL, and BNL), universities (University of Wisconsin and Ohio State University), international agencies (IRSN, CEA, JAEA, KAERI, and JRC-IE) and private consultation companies (Radiation Effects Consulting) were assembled to perform a gap analysis for sodium fast reactor licensing. Expert-opinion elicitation was performed to qualitatively assess the current state of sodium fast reactor technologies. Five independent gap analyses were performed resulting in the following topical reports: Idaho National Laboratory Robert Bari Brookhaven National Laboratory Robert Budnitz Lawrence Berkeley National Laboratory Jim Cahalan, Chris Grandy, Dave Wade Argonne National Laboratory Michael Corradini University of Wisconsin, Madison Richard Denning Ohio State University George FlanaganOak Ridge National Laboratory Steve Wright Sandia National Laboratories March 2010 FCRD-REAC-2010-0001268 DISCLAIMER This information was prepared as an account of work sponsored by an agency of the U.S. Government. Neither the U.S. Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness, of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. References herein to any specific commercial product, process, or service by trade name, trade mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the U.S. Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof. Advanced Sodium Fast Reactor Accident Initiators/Sequences Technology Gap AnalysisMarch 2010 9 SUMMARYAn advanced Sodium-Fast-Reactor (SFR) is being evaluated by DOE to provide the capability to transmute actinides and enhance the long-term fissile fuel-supply for fission reactors. An essential element in this evaluation is whether an adequate technology base exists to support the safety case for an SFR.The panel concluded that there are no major technology gaps in preparing a safety case for an advanced SFR, so long as one stays with known technology. Defining the current state of knowledge was therefore an important activity of the panel, along with the context in which it can be used for licensing. Significant potential departures from known technology were identified, such as development of fuel containing high concentrations of minor actinides, which will require further investments in R&D both to develop the technology and to develop an adequate safety case.