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991.
A method for measuring the dead time of an optoelectronic streak camera with different linear sweep ranges is described. The proposed method was used for the PN-1 streak camera. Photographs of the time-resolved emission of a DRSh350-2 mercury arc flash lamp for linear sweep ranges of 50 and 100 ns are presented. The dead times of the PN-1 streak camera for linear sweep ranges of 25, 50, and 100 ns were 5, 75, and 105 ns, respectively. The photographs of time-resolved second-harmonic spectra emitted by plasmas of copper and aluminum targets that were obtained in experiments on the interaction of nanosecond laser radiation with the matter using a streak camera are presented.  相似文献   
992.
993.
It is shown that by measuring the magnetic field in a specially shaped hole made in the magnetic circuit of a measuring transducer and the tangential component of the magnetic field in the transducer’s interpolar space near the surface of an object being magnetized, it is possible to locally determine the relative values of the magnetic properties of the test-object substance. The physical rationale is provided for a technique that makes it possible to determine the entirety of hysteresis characteristics and significantly expand the ranges of measurement of magnetic properties. The difference is established between the structural sensitivities of magnetic properties locally determined in terms of “flux–internal field” (the properties of matter) and “flux in the product–current in the windings” (the properties of “body”) coordinates. It is shown that it is possible and expedient to simultaneously measure and jointly analyze the magnetic characteristics of matter and “body”. Information is provided on the DIUS-1.15M mobile hardware–software system, intended for implementing single- and multiparameter techniques of monitoring the structure–phase and stress–strain states of ferromagnetic materials and objects based on the proposed measurement procedures.  相似文献   
994.
The presentation of high-tech projects (including research and development projects) submitted to funding competitions is considered. Two-stage development of such presentations is proposed. The first step is to ensure that the selected set of characteristics is representative and may be estimated with sufficient precision. The next step is to introduce a mathematically formalized business model of the project, permitting its financial evaluation. This model must adequately and transparently identify the financial potential of the economic cluster that will implement the submitted project. Embodied in software, this model must support stress testing of the high-technology project and optimization of its characteristics.  相似文献   
995.
Assessment of the difficulty and cost of research and development relating to distributed aviation systems is considered. A problem is that the participants in development projects may assess them subjectively. Analysis of the basic methods used to assess the difficulty and cost of research and development in industry and associated fields reveals their deficiencies.  相似文献   
996.
A mechatronic motorized spindle with hydrostatic bearings and a contact-free piezohydraulic generator of resonant axial spindle microoscillations is proposed. The boundary problem is solved for a nonsteady Reynolds equation in laminar motion, with no cavitation of the working fluid. On that basis, analytical formulas are derived for the dynamic-pressure distribution of the working fluid and the dynamic axial force created in the gap of the piezohydraulic generator.  相似文献   
997.
A method for automatic determination of combustion regimes using flame images on the basis of a convolutional neural network on labeled data is under consideration. It is shown that the accuracy of regime classification reaches 98% on the flame images of a gas burner. The results of the operation of the convolutional neural network and classification using different linear models are compared.  相似文献   
998.
Various methods of spectral-spatial classification of hyperspectral data are reviewed. Papers devoted to the most popular ways of using spatial information for increasing the accuracy of classification maps are considered. It is shown that the best results are obtained by using preprocessing of “raw” data before the procedures of pixel-wise spectral classification. Disadvantages, limits, and possible directions for developing existing methods are investigated and analyzed.  相似文献   
999.
This work presents a method of formation of an accurate self-similar solution of the problem of hydrodynamic calculation of a wedge-shaped support (slide block, guide) operating in the presence of a lubricating material and melt of the guide. Based on the equation of motion of an viscous incompressible liquid for a “thin layer” and the expression for the energy dissipation rate, an analytical dependence is obtained for the profile of the melted surface of the guide. In addition, the main performance characteristics of the friction couple considered are defined. The influence of the parameter specified by the melt of the guide on the bearing capacity and friction force is estimated.  相似文献   
1000.
Urea–formaldehyde-bonded wood products are limited to interior nonstructural applications because of their poor durability under cyclic moisture or humid environments. The stability of solid-wood joints and particleboards can be enhanced by bonding with urea–formaldehyde adhesives modified with di- and trifunctional amines at an effective resin formaldehyde-to-urea mol ratio (F/U) of 1.6; however, particleboard formaldehyde emissions were not improved over those from boards made with unmodified adhesives and were unacceptably high. The relative effectiveness of selected modifications was investigated at resin form aldehyde-to-urea (F/U) molar ratios of 1.4 and 1.2 Solid-wood joints and particleboards made with modified adhesives, an unmodified adhesive, and a phenol formaldehyde (PF) resin were subjected to cyclic soak-dry (cyclic stress) treatments and moist-heat aging. Formaldehyde emissions from particleboards were also determined. At F/U 1.4, the resistance of solid-wood joints made with modified adhesives to cyclic stress and moist-heat aging was equal to that of PF-bonded joints and superior to that of joints bonded with unmodified adhesive. The resistance of particleboards made with modified adhesives was greater than that of boards made with unmodified adhesive but less than that of PF-bonded board. Solid-wood joints and particleboards made with F/U 1.4 resins performed better than did those made with F/U 1.2 resins. Particleboards made with F/U 1.2 resins had formaldehyde emissions well below the standard, and room temperature aging or bonding at high temperature reduced emissions substantially. © 1994 John Wiley & Sons, Inc. 1
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America.
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