ABSTRACT TACT: A SET OF MSC/PATRAN- & MSC/NASTRAN-BASED MODAL CORRELATION TOOLS

This paper describes the functionality and demonstrates the utility of the Test Analysis Correlation Tools (TACT), a suite of MSC/PATRAN Command Language (PCL) tools which automate the process of correlating finite element models to modal survey test data. The initial release of TACT provides a basic yet complete set of tools for performing correlation totally inside the PATRAN/NASTRAN environment. Features include a step-by-step menu structure, pre-test accelerometer set evaluation and selection, analysis and test result export/import in Universal File Format, calculation of frequency percent difference and cross-orthogonality correlation results using NASTRAN, creation and manipulation of mode pairs, and five different ways of viewing synchronized animations of analysis and test modal results. For the PATRAN-based analyst, TACT eliminates the repetitive, time-consuming and error-prone steps associated with transferring finite element data to a thirdparty modal correlation package, which allows the analyst to spend more time on the more challenging task of model updating. The usefulness of this software is presented using a case history, the correlation for a NASA Langley Research Center (LaRC) low aspect ratio research wind tunnel model. To demonstrate the improvements that TACT offers the MSC/PATRAN- and MSC/NASTRAN-based structural analysis community, a comparison of the modal correlation process using TACT within PATRAN versus external thirdparty modal correlation packages is presented

ABSTRACT SOUND TRANSMISSION THROUGH TWO CONCENTRIC CYLINDRICAL SANDWICH SHELLS

This paper solves the problem of sound transmission through a system of two infinite concentric cylindrical sandwich shells. The shells are surrounded by external and internal fluid media and there is fluid (air) in the annular space between them. An oblique plane sound wave is incident upon the surface of the outer shell. A uniform flow is moving with a constant velocity in the external fluid medium. Classical thin shell theory is applied to the inner shell and first-order shear deformation theory is applied to the outer shell. A closed form for transmission loss is derived based on modal analysis. Investigations have been made for the impedance of both shells and the transmission loss through the shells from the exterior into the interior. Results are compared for double sandwich shells and single sandwich shells. This study shows that (1) the impedance of the inner shell is muc

H.: " Modeling of Sound Transmission Through Shell Structures With Turbulent Boundary Layer Excitation

The turbulent boundary layer (TBL) pressure field is an important source of cabin noise during cruise of high subsonic and supersonic commercial aircraft [1-3, 6]. The broadband character of this excitation field results in an interior noise spectrum that dominates the overall sound pressure level (SPL) and speech interference metrics in the forward and midcabins of many aircraft. In the authors ' previou

OPTIMIZATION SURGICAL TACTICS FOR THE TREATMENT OF CLOSED ABDOMINAL INJURIES AND THE POSSIBILITY OF MINIMALLY INVASIVE INTERVENTIONS

<p><strong>Abstract: </strong>Closed abdominal injuries with injuries to the hollow organs of the abdominal cavity are accompanied by high mortality, which, depending on the nature of the injuries, ranges from 27% to 35%. In this regard, the authors reviewed the literature on surgical treatment tactics for these injuries.</p><p>The authors found that to date, the feasibility of various tactical concepts for correcting injuries in patients with combined abdominal injuries, the order of traditional and minimally invasive surgical interventions have not been determined, and a diagnostic and treatment algorithm for injuries to the hollow organs of the abdominal cavity during abdominal pain has not been developed. All these data serve as an objective basis for the need for further scientific research in this direction.</p><p><strong>Key words</strong>: Abdominal trauma, video-assisted procedure, injury, patient.</p&gt