Testing, investigating, and optimizing this type of memory cells call for the creation of a
fundamentally new type of information-measurement complex. At the start of these works,
there were no analogs of such a complex both in research and industry. There are special
and rather contradictory requirements on the characteristics of an information-measurement
complex to investigate and optimize the nonvolatile memory of a new generation.
When pulses of programming or deleting information (pulse duration: 10 ns, front: from 2 to
3 ns) act on a memory cell, simultaneous data reading (memory cell resistance measuring)
takes place. Memory cell resistance may vary in the range from several hundreds of ohms to
several hundreds of megohms. At a time constant of 3 ns and a resistance of 150 kiloohms
the effective capacity of the system, including the cell, conductors, and electronic circuit,
must not exceed 0.02 picofarads.
The creation of electronic devices with such parameters is a complicated scientific and
technical problem.
Data recording, reading, and deleting in a memory cell are determined by the size and
sequence of the corresponding electric pulses. Since the characteristics of individual resistive
elements are widely spread, a mode switching control based on fast feedbacks in current
and voltage is performed.
The complicated scientific and technical problem of organizing fast feedback (from 3 to 4 ns)
between the resistance measured and the pulse duration of programming or deleting has
been solved.
Sufficient complex phase stability and operating speed for recording and exchanging
information with a nanoelement in a molecular cell have been provided.
The program interface is implemented via a COM-object. This allowed planning and
performing experiments with any program packages supporting COM-automatization
(OrignPro, Matlab or Excel).
Stability and long-term cycling operation have been achieved in this information-
measurement electrometric complex for the memory element, which is based on modern
concepts of molecular electronics. Operation in a multi-bit mode with a typical time constant
of 3 ns at a cell resistance of 150 kiloohm has been ensured (Glavny et al., 2007).
7. Technical vision systems and multi-dimensional signal processing.
Information monitoring in the glass industry
The purpose of this work was to create an optoelectronic computer method for obtaining
information about the mass of a free falling object using its image, in other words, a
computer implementation of the well-known method of weighting judged ''by eye.''
In a classical method to measure the volume V of a complex-shaped body, the body is
divided along the vertical axis y by parallel sections of area S( y) and height Δ y. The total volume of the body is equal to the sum of N volumes of the thin truncated solids.
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Reconstructing the boundary shape requires a series of measurements of transverse sizes of
sections at all heights y by rotating the body about the vertical axis. If optical methods are
used for measurements, the plane projections of the body at different angles must be
recorded. A similar approach is used in tomography.
There exist certain classes of objects with topologically similar parallel sections where the
volume can be measured by recording a single plane projection. The topological similarity
means that any parallel section has an area S associated with a special transverse size (2 r) by
a coefficient ξ that does not change at any continuous scale transformation. In this case, the
condition
2
(
S y) = ξ ⋅ r ( y), y
∀ ∈[ a, b],ξ = const , is satisfied for any coordinate y.
Here, r is the distance from the vertical axis to the plane section boundary and ξ is a
topological calibration coefficient determined by the shape of the section boundary.
When the geometry of sections is determined optically, the volume V of a body with
topologically similar parallel sections is calculated by taking into account the topological
N
N
and geometrical calibrations as
2
V = lim ∑ (
S y
y
Δ K β ≈ ξ ⋅ ∑ r y y
Δ K β , where r( y)
n )
n n(
)
( n) n n( )
N→∞ n=0
n=0
is the projection of the transverse size of a body of revolution onto the observation surface as
a function of the coordinate y along the vertical axis. The geometrical calibration coefficient
K depending on the vertical coordinate y and parameter β is introduced to compensate for
the optical hardware distortions of the results of measurements of S and y. The coordinates a
of the lower edges and the coordinates b of the upper edges of the body are also determined
along the vertical axis.
A particular case of objects with topologically similar parallel sections is glass gobs formed
in the production of glass bottles. The shapes of gobs solidifying in flight are close to those
of bodies of revolution, and for the latter the condition of topological similarity of plane
sections is satisfied. To estimate the volume of such an object, it is sufficient to measure the
sizes of projections of sections r( y) onto the recording plane, given the topological ξ and geometrical K calibration coefficients. The measurement error is due to inaccurate
determination of transverse size projections at various coordinates r( y) and violation of
topological similarity. An important property of the objects with topologically similar
parallel sections is insensitivity of volume estimation by plane images to possible vertical
axial deformations.
The spatial coordinates r( y), a, and b are determined by a program method of analyzing bitmap images. Spatial coordinates x and y in the image plane are selected and tied to an
absolute system of coordinates. The image of a glass gob (A) is transformed into a video
signal by a TV camera by line-wise scanning. A scanning coordinate-sensitive photodetector
(B) ''cuts'' the droplet projection into lines. In this case, each line corresponds to one parallel
section of the object.
This method was implemented in an information monitoring system for the glass industry.
Now it is used as a scientific basis for engineering by other organizations. The system was
created for obtaining noncontact real-time information about the masses of freely falling hot
gobs of fluid glass in the production of glass works (bottles). The system operation is
preliminary optical processing of the images of freely falling hot glass gobs, introducing the
video signal into a computer, real-time analyzing the video flow, extracting the geometrical
information, calculating the volume and mass of gobs, and statistical processing of the
results.
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The inner volume of a bottle is determined by the mass of the glass gob (the outer bottle
sizes are determined by the geometry of the mould). In dosing fluid glass, the glass
parameters are near the crystallization point and greatly affect the stability of operation of
the gob former. The number of rejects reaches 30 to 45 %. The mass of a glass gob can be
measured only ''by eye,'' as the droplet falls from the gob former to the mould of a suck-and-
blow automatic machine. The glass is hot; there are intense convective and aerodynamic
stratified flows and strong refraction. The air has considerable amounts of aerosol particles
produced by the black-lead lubrication of the gob former scissors. In two-three hours, the
unprotected optical devices become completely dirty. The systems used for measurement
should not hamper the operation of the available technological equipment and should be
located at a distance of no less than 3 to 10 meters from the objects measured. The required
accuracy is 0.5 %.
In the system, information undergoes some successive transformations, and each of them
introduces its own errors. Temperature is a major perturbing factor. This parameter
affects the quantum yield of the photomatrix, the levels of its dark current, the leakage
currents of all semiconductor elements, and the accuracy of binding to the levels of black
and white in the processing chain of a TV signal. It has been shown that for obtaining an
accurate and reproducible estimate of the spatial boundaries of a self-luminous object
with an error of 0.2 %, the video camera should be thermally stabilized with an error not
exceeding 0.1°C.
A second important factor is luminosity of the object. The temperature of hot glass gobs is
about 1000°C, and they have high luminosity. The temperature and luminosity of their
surface can change due to intensive cooling by a cold air flow. A method to stabilize the
threshold discrimination level of a video signal has been developed. This method performs
statistical estimation of the image, levels of black and white, and provides accurate spatial
discrimination of the boundaries when the luminosity of the object changes.
A method for passive aerodynamic protection of the optical surfaces of an information-
measurement system was proposed. With this method, no atmospheric aerosol can get into
the boundary layer, the optical surfaces are not dirty, and the time of undisturbed operation
of the system is increased from 3 to 4000 hours.
The image of a falling gob of molten glass is formed by a receiver based on a video matrix. A
video signal comes to the computer of a workstation for subsequent real-time processing.
The workstation software receives video flow from a TV camera, detects the object in the
field of vision, binds the object to the frame boundaries, and performs spatial filtration,
spectral selection of the image, noise elimination, and amplitude discrimination by the
Heaviside step function. After this, the gob mass is calculated. The calculated mass values
are kept in a local database of the workstation. The monitor screen shows the gob mass
variation in real time.
If the gob mass is greater than some given limits, the program generates warning and
control signals. With these signals, an operator (or an actuating mechanism) introduces
corresponding corrections to the technological process. Three watchdog timers controlling
the major program modules maintain the operation of the workstation software.
A real-time information monitoring system for noncontact measurement of the masses of
freely falling hot glass gobs is used by the Ekran (Novosibirsk). This low-cost system is used
to fabricate glass bottles. The system provides noncontact technological control of the
masses of hot glass gobs and generates warning signals when the mass of gobs exceeds the
tolerance zone boundaries. The mass measurement error is between 0.5 and 1 %. The use of
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monitoring based on this method in the glass industry has decreased the number of rejects
by a factor of 3 to 5 (Meledin et al., 1999, 2000, 2001, 2002).
8. Medicine. Optoelectronic complexes for endoscopy
Endoscopy is one of the most important trends in the development of medical science and
practice. Endoscopic operations are widely used for diagnostics and treatment of various
human diseases. Karl Storz endoscopes developed in Germany and used in 140 countries
are a world standard. Their quality meets the most stringent requirements of medical
diagnostics, and the cost reaches a considerable amount of 2000 to 5000 US dollars. Since the
optical devices in existing endoscopes are complicated and expensive, they cannot be
employed on a mass scale and easily used in scientific investigations and experiments.
The purpose of this work was to create optoelectronic endoscopic complexes of a new
generation, which permit operation with disposable tools in medicine, scientific
investigations and experiments, and technical introscopy.
A standard endoscope has several high-quality image-transmitting rod lenses with
complicated centering (H. Hopkin's scheme) and a fiber highlighter. Because of high
temperature, humidity, autoclaving, and chemical treatment, frequent sterilization of the
endoscope reduces its lifetime and worsens image quality. The propagation of HIV and
acute viral hepatitis makes the problem of creating disposable sterile endoscopes especially
important. The performance of hundreds of operations on different patients with the same
endoscope without reliable sterilization creates a moral and ethical problem for the doctors
and a serious risk for the patients. The limited reliability of modern endoscopes due to high
sensitivity of lens centering to mechanical deformations is also a problem.
Our endoscope has been created as a means of optical diagnostics of multiphase flows in
closed cavities. A new optical scheme for the endoscope has been created. Its advantages are
a high resolution, high reliability, small cost (20 to 100 US dollars), simple construction at
good image quality, and high sterility owing to the use of disposable tools.
One can see from the comparative table that the parameters, except for the number of lenses,
depth resolution, and admissible deformation, do not differ considerably. A major
advantage of this endoscope is that it has a small number of lenses, since the complexity of
an endoscope is determined by the complexity of its optics. Advantages of the endoscope
are also simplicity, easy assembly and disassembly, and large admissible deformations. The
endoscope allows the use of disposable elements of plastic or traditional optics. A number of
endoscopes with these advantages have been created.
A scientific problem is obtaining information about the frequency-contrast characteristic and
distortion of the optical and optoelectronic schemes of endoscopes under considerable
uncompensated aberrations. At the start of this work, there were no suitable methods. A
method for obtaining information about the parameters of endoscopes has been proposed
and validated. It is based on the reconstruction of the test signal by using a distorted image
of the test object, calculation of the frequency-contrast characteristic as the ratio of cross
spectrum of the input optical signal and the reconstructed test one to spectrum of the
reconstructed test signal, and determining the spatial distribution of distortion curves. The
method has been implemented on the above-mentioned optoelectronic stand for obtaining
information about the characteristics of endoscopes.
This work was initiated, supported, and awarded by the technology park of the city of
Katzrin, Golan (Israel). An international company, Optiscope Technologies, Ltd., has been
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387
created. For these endoscopes, a number of patents, among them two American patents,
have been taken out. Now further development of the technology of precision plastic casting
of a disposable endoscope is being performed by a Carl Zeiss daughter enterprise in
Germany (Meledin, 2008).
9. Machine building. Optoelectronic diagnostics of coordinates and shapes
of 3d objects
In power engineering and machine building, there is a wide class of products. Specifically,
these are: low-rigid large products with complex shapes, such as blades of hydroturbines,
steam and gas turbines, and compressors, box and shell casings, airscrews of flying vehicles,
screw propellers of ships, impellers, covering discs, etc. The cost of large blanks is high, and
requirements on the quality of products are very rigid. Therefore, the problem of high-
precision control of coordinates and shapes of 3D objects at all stages of mechanical
treatment is very important.
The purpose of this work was to create new methods and information systems as refined
and easy to manufacture as possible for obtaining information about the full geometry of 3D
objects with sizes from several millimeters to tens of meters.
A new method for stable processing of sets of spatially modulated images with a stepwise
shift has been proposed. It minimizes the error in determining the phase with noise of
constant mathematical expectation and variance. In this case, the phase difference
estimation of sets of spatially modulated fields is independent of the background intensity
distribution.
The method is successfully used in the form of a program code. A generalized algorithm to
obtain a solution to a system of transcendental equations at arbitrary phase shifts has been
constructed. The complexity of the algorithm with respect to the number of interference
patterns with different phase shifts has been estimated. The method is insensitive to
additive noise with constant mathematical expectation and variance. An estimate of the
root-mean-square deviation of the phase obtained and the reconstruction accuracy of the
relief surface of the object measured has been obtained.
The method is used in an information-measurement system to obtain information about the
geometry of 3D objects. The object under investigation is sequentially illuminated by a
structured light, which is a system of parallel bright halftone bands a constant spatial
frequency and linearly varying shift of the initial phase. Phase triangulation and the method
of phase steps are used to reconstruct the shape of the surface investigated. The method is
insensitive to additive random noise and the illumination source and receiver (video
camera) characteristics.
The considerable advantages of the method are used in an information-measurement
system. In this system, an office projector for exposing objects with typical sizes of tens of
meters is used as an illuminator and spatial modulator (Dvojnishnikov et al., 2010).
The information-measurement system created on the basis of the method of stable
processing of sets of spatially modulated images with a stepwise shift has modern
characteristics, and some parameters of the system surpass those of existing systems. Some
peculiarities of the system are as follows: high accuracy of measurements, which is
independent of the reflective properties of the surface, automatic calibration and verification
of data, dynamic real-time synthesis of images of the surface measured, automatic
comparison of measured data with model data, adaptive generation of the structure of
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lighting of the object investigated to identify its problem zones, and simultaneous parallel
measurement of coordinates at more than 600,000 points (Meledin, 2010).
10. Optoelectronic diagnostics in atomic power engineering
10.1 Three-dimensional velocity fields of heat carrier flow in fuel assembly of power
reactor
To raise competitive capacity of Russian atomic plants and substantiate safety of the active
zones, new methods should be created for obtaining experimental information about the
heat-exchange and hydraulic characteristics of water-moderated water-cooled power
reactors. The safety can be increased by validating the reserves prior to heat exchange crises
determined by the construction of active zones with different spacer grids and flow
turbulizers. At the start of this work, there was no detailed comparative information about
the fields and turbulent velocity pulsations in assemblies with different spacer grids for
geometrical and operational conditions typical for water-moderated reactors.
Since the thermal-hydraulic processes taking place in an assembly are very complicated, full
theoretical calculation of such parameters is not possible. The 1D methods used at present
provide only conservative forecasts, and the 2D and 3D methods need data on the turbulent
characteristics of flows and corresponding information obtained experimentally. The
absence of reliable and detailed experimental information hinders not only effective design
of the active zone elements of reactor plants, but also development and verification of the
corresponding calculation codes.
The purpose of the work was to create a new method for obtaining information about the
local and integral hydrodynamic characteristics of heat carrier flows in models of fuel
assemblies with various spacer grids.
A new combined method for obtaining information about the detailed local and integral
hydrodynamic characteristics of heat carrier flows in a model of fuel assembly with spacer
grids has been proposed. The method is based on semiconductor laser Doppler
anemometry, video anemometry, and immersion of the optically transparent reactor model
into an immersion liquid with a refraction coefficient equivalent to a model one.
If a phase object - a transparent body - is immersed into a liquid with a refraction coefficient
equal to that of the object material, the object will be invisible. However, the object
boundaries, which determine the hydrodynamics and heat exchange, will remain. The
structure of the flows will also remain. There will be no refraction and scattering of light by
the boundaries of the object. Thus, it will be possible to obtain reliable information about the
processes screened by the object boundaries by optical methods (notice that this idea goes
back to H.G.Well's novel ''The Invisible Man''). For the first time, it is possible to obtain
information from the previously inaccessible space zones by noncontact nondestructive
methods.
The method has been tested experimentally with a model problem on the propagation of the
heat carrier flow induced by a rotating central rod and disc in a system with multiple rods
imitating fuel elements of a power reactor. Semiconductor laser Doppler anemometry and
computer video anemometry are used in this method to obtain information about the heat
carrier flow at a horizontal section of the reactor model. The method algorithms use spatial
transformations that can obtain information at any spatial section of the fuel assembly.
For the first time, 3D vector velocity fields and fields of velocity modules of the heat carrier
flows excited by a rotating central rod or a disc have been obtained, and 2D and 3D
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389
characteristics of the flows have been determined. The efficiency of turbulizing and mixing
grids of the models of power reactor fuel assemblies has been estimated. For the first time,
experimental information about 2D and 3D kinematic characteristics of heat carrier flows,
which can be used to verify calculation codes and fuel assembly models of power reactors,
has been obtained (Bolshov et al., 2006; Meledin, 2006).
10.2 Geometry of spacer grid of power reactor fuel assembly
A method to obtain information about the geometry, shading zone, and spatial structure has
been proposed. It is used to obtain, by program methods, spatial information from scanned
images of spacer and intermixing grids of fuel assemblies of power reactors.
It has been shown that this method can be implemented to create a noncontact information
system to determine the shading areas of spacer and mixing grids with an absolute
measurement error of about 2 μm by a standard modern scanner and specially developed
software.
An algorithm to process scanned images has been developed. It consists of the following
sequence of operations: obtaining of the initial scanned image of the grid; normalization and
adaptive threshold discrimination; morphological filtration; segmentation; adaptive