A wireless sensor network of rectangular mesh confi guration and between 20 and 260 clusters of smart sensors is studied. The probability of failure-free operation and the duration of the polling cycle are estimated.
The method of partially depolarized dynamic light scattering is applied to measurements of gold nanorods dimensions in liquids using translational and rotational diffusion coefficients. Compared with the known methods, the new method makes it possible to lower the power of the existing laser radiation and to increase the data set for solving the inverse problem. Nanorod lengths calculated from the diffusion coefficients are in agreement with TEM data. Aspect ratios calculated from extinction spectra in the plasmon resonance domain are in better agreement with TEM.
The intellectual three-channel frequency-code converter with high vitality is considered. Auto diagnostics and auto calibration of converter are performed without current conversion interruption.
Theoretical approaches to the construction of a spectrometric diamond detector of fluxes of ionizing radiation are considered. The device is intended for continuous monitoring of the radiation conditions onboard space vehicles for quickly arriving at decisions as regards active protection and prediction of the remaining life of space transportation systems.
Spectroradiometry of ultraviolet radiation
A method is proposed for constructing radial type microwave devices forming a uniform temperature distribution throughout the volume of pipes made of polymer composite materials The results of theoretical and experimental investigations of the temperature distribution across the thickness of the pipe material are given. The advantages of microwave technologies for curing polymer composite aterials compared to traditional methods are shown.
The creation of the center of metrological assurance of nanotechnologies and assessment of the compliance of the products of the nanoindustry
A fuel flow rate transducer design for a manned transport spacecraft is proposed. It is based on the principle of measuring the phase of the useful signal carrier frequency. This scheme significantly improves the stability of the instrument against mechanical interactions and provides more accurate measurements of the amount of fuel consumed by the spacecraft.
A wireless sensor network with a regular, 3D rectangular array structure is studied. The network consists of between 16 and 512 clusters, with between 1 and 5 intelligent sensors per cluster. Analytical expressions are obtained for the probability of failure-free network operation, polling cycle time, and node efficiency. A cyclic polling pipeline algorithm is examined.
An example of the construction of contactless vibration sensors based on fiber-optical displacement transducers with external modulation. Considered sources of measurement inaccuracy and methods of reducing them. Designed and tested the prototype of adaptive fiber-optical vibration sensor.
The principle underlying the construction of a time-type analog-to-digital displacement transducer and a generalized flow chart of a transducer that converts displacements into time intervals are considered. It is mathematically proved that the functional dependence of the length of the time interval on the measured displacement is linear.
The method of construction of the radial type microwave devices forming the uniform temperature distribution in the volume of polymer composite pipes is suggested. The results of theoretical and experimental studies of the temperature distribution along the thickness of the pipe material are presented. The advantages of microwave technology for the curing of polymeric composite materials compared to traditional methods are shown.
Theoretical and experimental research results in the field of high-performance microwave technologies of sheet materialsare presented. Sections of two-dimensional periodic slow-wave systems are used as heating elements. Divergence of theoretical and experimental temperature distribution characteristics in the sheet material does not exceed 3%, and the temperature deviation in the material from the nominal temperature value does not exceed 5%.
In this paper we analyze details of bipolar transistors and MOSFETs electrical characteristics measurement in the presence of neutron, electron and gamma irradiation. An automated measurement subsystem is developed with its core being a measurement kernel comprising a set of measurement instrumentation as well as methods of measurement and data processing for irradiated transistors of various types. Provided are several examples of the subsystem application to BJTs and MOSFETs radiation hardness investigation as well as extraction of their SPICE model parameters for circuit design.