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The paper presents experimental data on the absolute values of the radiation intensity in the wavelength range of 6.6–32 nm for a stainless steel target excited by a Nd:YAG laser with parameters λ = 1064 nm, Epulse = 0.45 J, τ = 4 ns, = 10 Hz. The results are of interest for various applications using laboratory laser-plasma sources of soft X-ray and extreme ultraviolet radiation. [ABSTRACT FROM AUTHOR]

The work is devoted to the development, fabrication and analysis of broadband W/Si multilayer mirrors for a broadband monochromator, calculated for the spectral range of 7–10 keV. The possibility of using the stacking approach to obtain multilayer mirrors with a reflection coefficient of about 30% and a spectral bandwidth ΔE/E of about 20% is shown. The results of measurements of the angular and spectral reflection curves of the mirror obtained on a laboratory diffractometer and on a synchrotron in Novosibirsk are presented. [ABSTRACT FROM AUTHOR]

The operation of our atmospheric quantum cryptography system using the BB84 protocol and polarization coding is experimentally studied. The distribution rate of the sifted quantum key and the quantum bit error rate in the key remained constant for 1 hour and were bit s and , respectively, at the distance of 20 m between the transmitter and receiver. The minimum possible transmittance of a quantum channel, ensuring the security of a quantum key, is calculated for the given parameters of the system [ABSTRACT FROM AUTHOR]

The reflection coefficient and microstructure of Mo/Be multilayer mirrors are studied as functions of Γ, i.e., the ratio of the Mo-layer thickness to the period dp. The thickness and period of the layers are studied using X-ray diffraction (wavelength 0.154 nm). Clearly defined high-intensity Bragg-reflection peaks indicate good reproducibility of the layer thicknesses over the depth of the multilayer structure and the high quality of interfaces. The reflectivity of the mirror at a wavelength of 11.4 nm is maximum 62% at Γ = 0.42. It sharply decreases at higher and lower values of Γ. Both Mo and Be layers at Γ = 0.42 are polycrystals, which are studied using X-ray diffraction and Raman spectroscopy, respectively. It is also found that the sizes of crystallites almost coincide with the thicknesses of Be and Mo layers in the period. [ABSTRACT FROM AUTHOR]

Background/objective: Different testing paradigms have been proposed to investigate perceptual self-motion thresholds. They can differ regarding the amount of possible motions that patients have to choose from. Objective of this study was to compare the two-option paradigm and twelve-option paradigm, to investigate whether reducing the choice options significantly influences the reported thresholds of self-motion perception of healthy subjects. Methods: Thirty-three volunteers with no prior vestibular complaints were included and sequentially tested with both paradigms at a random sequence. Perceptual self-motion thresholds were measured using a hydraulic motion platform in the absence of external visual and auditory cues. The platform delivered twelve different movements: six translations and six rotations. Each subject had to report the correct type and direction of movements. Thresholds were determined by a double confirmation of the lowest threshold, in combination with a double rejection of the one-step lower stimulus. Perceptual self-motion thresholds of both paradigms were compared using the mixed model analysis. Results: The twelve-option paradigm showed significantly higher reported thresholds for yaw rotations and translations left, right and down (p < 0.001), compared to the two-option paradigm. No statistical difference was found for rolls and translations up. No significant gender effect, learning effect and carry-over effect were present in any of the applied motion directions. Conclusion: Reported thresholds of self-motion perception of healthy subjects are influenced by the testing paradigm. The twelve-option paradigm showed significantly higher thresholds than the two-option paradigm. Results obtained with each testing paradigm should, therefore, be compared to paradigm-specific normative data. [ABSTRACT FROM AUTHOR]

Objective: Current diagnostic criteria for bilateral vestibulopathy (BV) primarily involve measurements of vestibular reflexes. Perceptual self-motion thresholds however, are not routinely measured and their clinical value in this specific population is not yet fully determined. Objectives of this study were (1) to compare perceptual self-motion thresholds between BV patients and control subjects, and (2) to explore patterns of self-motion perception performance and vestibular function in BV patients. Methods: Thirty-seven BV patients and 34 control subjects were included in this study. Perceptual self-motion thresholds were measured in both groups using a CAREN platform (Motek Medical BV, Amsterdam, The Netherlands). Vestibular function was evaluated (only in BV patients) by the caloric test, torsion swing test, video head impulse test of all semicircular canals, and cervical- and ocular vestibular-evoked myogenic potentials. Differences in thresholds between both groups were analyzed. Hierarchical cluster analysis was performed to visualize patterns between self-motion perception and vestibular function within the group of BV patients. Results: Perceptual self-motion thresholds were significantly higher in BV patients compared to control subjects, regarding nearly all rotations and translations (depending on the age group) (p ≤ 0.001). Cluster analysis showed that within the group of BV patients, higher perceptual self-motion thresholds were generally associated with lower vestibular test results (significant for yaw rotation, caloric test, torsion swing test, and video head impulse test (p ≤ 0.001)). Conclusion: Self-motion perception is significantly decreased in BV patients compared to control subjects regarding nearly all rotations and translations. Furthermore, decreased self-motion perception is generally associated with lower residual vestibular function in BV patients. Trial registration: Trial registration number NL52768.068.15/METC [ABSTRACT FROM AUTHOR]

There are various eye-tracking methods and the most common among them are methods of videooculography (VOG) and electrooculography (EOG). These methods are based on completely different physical principles, and accordingly, the signals received during the eye movements recording have different noise sources. Eventually, both methods register the same mechanical movement, and as respect, they should give consistent results. In this regard, the experimental study and analysis of accuracy of VOG and EOG while visual saccades registration performed using these methods of oculography simultaneously were carried out. 12 horizontal saccades to the left with an average amplitude of Vleft = 150±50 deg/s and 10 saccades to the right with an average amplitude of Vright = 160±50 deg/s were recorded simultaneously by these two methods. The signals were processed by a low-pass filter with a cut-off frequency of 10 Hz and synchronized in time using crosscorrelation. Further, the saccades were averaged separately for each system and the left-right direction. The comparison of visual saccades was carried out using a linear regression model of the dependence of the eye velocity, recorded by EOG, on the eye velocity, recorded by VOG. A statistically significant good agreement of the eye velocities recorded using EOG and VOG during horizontal saccades was found. The obtained results of experimental studies have shown that despite the completely different physical principles these two methods based on and the presence of measurement errors of different nature, on average, the results of the eye movement registration by VOG and EOG systems are in excellent agreement with each other. The advantage of using EOG for measuring saccades and evaluating the vestibulo-ocular reflex (VOR)is shown. [ABSTRACT FROM AUTHOR]

The design and fabrication of a single photon detector based on InP/InGaAs/InP single-photon avalanche diodes (SPADs) operating in Geiger mode at a telecommunication wavelength of 1550 nm are discussed. The SPAD design, the method for obtaining InP/InGaAs/InP heterostructures by molecular beam epitaxy, fabrication of SPAD chips using planar technology, and specific features of selective zinc doping of -regions in the InP layer of the developed electronic circuits for measuring main SPAD parameters are described. Preliminary results of measurements of the parameters of the fabricated SPADs are presented. [ABSTRACT FROM AUTHOR]

Unilateral or bilateral vestibular hypofunction presents most commonly with symptoms of dizziness or postural imbalance and affects a large population. However, it is often missed because no quantitative testing of vestibular function is performed, or misdiagnosed due to a lack of standardization of vestibular testing. Therefore, this article reviews the current status of the most frequently used vestibular tests for canal and otolith function. This information can also be used to reach a consensus about the systematic diagnosis of vestibular hypofunction. [ABSTRACT FROM AUTHOR]

Introduction: Bilateral vestibulopathy (BVP) can affect visual acuity in dynamic conditions, like walking. This can be assessed by testing Dynamic Visual Acuity (DVA) on a treadmill at different walking speeds. Apart from BVP, age itself might influence DVA and the ability to complete the test. The objective of this study was to investigate whether DVA tested while walking, and the drop-out rate (the inability to complete all walking speeds of the test) are significantly influenced by age in BVP-patients and healthy subjects. Methods: Forty-four BVP-patients (20 male, mean age 59 years) and 63 healthy subjects (27 male, mean age 46 years) performed the DVA test on a treadmill at 0 (static condition), 2, 4 and 6 km/h (dynamic conditions). The dynamic visual acuity loss was calculated as the difference between visual acuity in the static condition and visual acuity in each walking condition. The dependency of the drop-out rate and dynamic visual acuity loss on BVP and age was investigated at all walking speeds, as well as the dependency of dynamic visual acuity loss on speed. Results: Age and BVP significantly increased the drop-out rate (p ≤ 0.038). A significantly higher dynamic visual acuity loss was found at all speeds in BVP-patients compared to healthy subjects (p < 0.001). Age showed no effect on dynamic visual acuity loss in both groups. In BVP-patients, increasing walking speeds resulted in higher dynamic visual acuity loss (p ≤ 0.036). Conclusion: DVA tested while walking on a treadmill, is one of the few "close to reality" functional outcome measures of vestibular function in the vertical plane. It is able to demonstrate significant loss of DVA in bilateral vestibulopathy patients. However, since bilateral vestibulopathy and age significantly increase the drop-out rate at faster walking speeds, it is recommended to use age-matched controls. Furthermore, it could be considered to use an individual "preferred" walking speed and to limit maximum walking speed in older subjects when testing DVA on a treadmill. [ABSTRACT FROM AUTHOR]

The smoothing effect of thin silicon films used as buffer layers in multilayer Be/Al mirrors optimized for wavelengths longer than 17.1 nm has been investigated. The objects of investigation have been near-normal incidence (an angle of incidence of 88°) and grazing incidence (33.5°) mirrors. This effect has been observed in multilayer Be/Si/Al mirrors with periods of up to at least 29 nm. For normal incidence mirrors optimized for a wavelength of 17.14 nm, a record-high value of the peak reflection coefficient, 62.5%, has been achieved at spectral selectivity λ/Δλ = 59. The temporal stability of the mirrors has been studied. [ABSTRACT FROM AUTHOR]

We describe the method for increasing the efficiency of holographic diffraction gratings (HDGs) intended for operation in the X-ray wavelength range. We describe the procedure of processing of HDG surface for reducing the amplitude and roughness of grooves. For reducing the groove amplitude, we have used Xe ions with an energy of 600 eV, while ion polishing was performed with Ar ions having an energy of 800 eV. It is shown that, after ion polishing, the diffraction efficiency of the grating at a wavelength of 4.47 nm increases by almost four times. [ABSTRACT FROM AUTHOR]

The latest experimental results of studying beryllium-containing multilayer mirrors are reviewed. The mirrors are of interest for projection nanolithography, solar astronomy, X-ray microscopy, and other applications. It is shown that for a number of ranges beryllium-containing multilayer mirrors outperform the world analogues in their X-ray optical characteristics. [ABSTRACT FROM AUTHOR]

The performance of multilayer Mo/Si mirrors with B4C and Be spacers near a wavelength of 13.5 nm has been studied. It has been shown that four-component Mo/Be/Si/B4C mirrors outperform Mo/Si and Mo/Si/B4C mirrors in reflection coefficient by 2.0 and 1.3%, respectively. In addition, Mo/Si mirrors offer the widest transmission band width at half maximum (Δλ1/2 = 0.535 nm). An explanation for these findings has been given. [ABSTRACT FROM AUTHOR]

Aperiodic multilayer mirrors (AMMs) optimized for uniform reflection within the bands of 16.5–21 and 28–33 nm are calculated by the genetic algorithm for the CORTES project. The comparative characteristic of traditional Mo/Si AMMs and beryllium-containing Mo/Be, Mo/Be/Si, Al/Be, and Mg/Be systems is given. It is demonstrated that Mo/Be/Si AMM is more preferable within the wavelength range of 16.5–21 nm, while Mg/Be AMM with a protective aluminum coating is more preferable within the band of 28–33 nm, being two and a half times superior to the corresponding Mo/Si AMM in its reflectivity. [ABSTRACT FROM AUTHOR]

Conventional Mo/Si mirrors and mirrors with B4C and Be barrier layers, designed for reflection at wavelengths around 13.5 nm, are fabricated using magnetron sputtering and studied. Their reflectance is measured at different grazing angles and at different wavelengths. Four-component multilayer mirrors of the Mo/Be/Si/B4C type are shown to surpass, in terms of the reflection coefficient, their Mo/Si and Mo/Si/B4C counterparts by 2 and 1%, respectively, at wavelengths of incident radiation of 12.4, 12.7, 13.0, and 13.5 nm. [ABSTRACT FROM AUTHOR]

A set of multilayer X-ray mirrors for an upgraded version of the double-mirror monochromator installed on the VEPP-5 synchrotron of the Budker Institute of Nuclear Physics is fabricated, its constituent parts are optimized, and its X-ray optical characteristics are studied. Due to the use of seven subbands, for each of which an optimal pair of materials is chosen, the mirror set ensures high reflection coefficients—ranging from 10 to 75%— for a wide range of photon energies from 80 to 3000 eV and wavelengths from 0.413 to 15.48 nm. The principles of optimization of material pairs are reported. For the first time, multilayer mirrors based on the W/Be pair of materials are fabricated and studied. [ABSTRACT FROM AUTHOR]

We propose a new approach to optimization of electrical stimulation of the vestibular nerve and improving the transfer function of vestibular implant. A mathematical model of the vestibular organ is developed based on its anatomy, the model premises, 3D-analysis of MRI and CT images, and mathematical description of physical processes underlying propagation of alternating electric current across the tissues of vestibular labyrinth. This approach was tested in vitro on the rat vestibular apparatus and had been examined anatomically prior to the development of its mathematical model and equivalent electrical circuit. The experimental and theoretical values of changes of the gain—phase characteristics of vestibular tissues in relation to location of the reference electrode obtained in this study can be used to optimize the electrical stimulation of vestibular nerve. [ABSTRACT FROM AUTHOR]

Comparative analysis of the groups of patients with idiopathic bilateral vestibular hypofunction and a group of vestibulopathy patients with vertebrobasilar insufficiency demonstrated identity of the basic and additional diagnostic parameters in these syndromes as well as similarity in clinical diagnostic and anamnesis data. In all cases, functional assessment of endothelium-dependent vasodilation and selected biochemical marker sICAM-1 revealed endothelial dysfunction. Drug correction of endothelial dysfunction positively affected the manifestations of major and minor features of the syndrome, which confirmed the contribution of endothelial functional disturbances to the pathogenesis of bilateral vestibular hypofunction. [ABSTRACT FROM AUTHOR]

An electric model of current transmission through tissues of the vestibular labyrinth of a patient is suggested. To stimulate directly the vestibular nerve in surgical operation, terminations of the electrodes are implanted through the bone tissue of the labyrinth into the perilymph in the vicinity of the vestibular nerve. The biological tissue of the vestibular labyrinth surrounding the electrodes and having heterogeneous composition possesses conductive and dielectric properties. Thus, when a current pulse from the vestibular implant is applied to one of the electrodes, conductive disturbance currents may arise between the electrodes and the vestibular nerves that can significantly deteriorate the direct signal quality. To study such signals and to compensate for the conductive disturbance currents, an equivalent electric circuit with actual electric impedance properties of tissues of the vestibular system is suggested, and the time parameters of the conductive disturbance current transmission are calculated. It is demonstrated that these parameters can reach large values. The suggested electric model and the results of calculations can be used for perfection of the vestibular implant. [ABSTRACT FROM AUTHOR]

Results are presented from experimental and theoretical studies of the dependence of the rate of quantum key distribution on the average number of photons in a laser pulse. The experimental data are obtained using atmospheric and fiberoptic experimental setups for a quantum key distribution based on the BB84 protocol. [ABSTRACT FROM AUTHOR]

Application of laser radiation with a wavelength of 1.07 μm and intensity of ~10 W/cm used on damaged gas wells for remote cutting of metals can be inefficient on damaged oil wells owing to a large value of the mean coefficient of radiation absorption by the oil flame of ~0.1 cm. It was shown that, when the radiation with the intensity increased to 10 W/cm propagated through this flame, the absorption coefficient decreased rapidly and, in the intensity range of 10-10 W/cm, it stabilized at a very low level of 5 × 10-10 cm. Experimental investigations on the conditions of remote cutting of metal plates from 1.5 to 60 mm in thickness by radiation of a cw ytterbium fiber laser with a power up to 7.5 kW at the radiation intensity of 10-10 W/cm on the metal surface were performed. It was found that, in a majority of practically important cases, such main parameters as drilling time, maximum cutting velocity, and cutting efficiency exceeded those at the radiation intensity of ≤10 W/cm. [ABSTRACT FROM AUTHOR]

The possibility was shown of decreasing the temperature of softening of ED-8 brand high-molecular-weight solid epoxy oligomer by means of creation of mixtures with DER-332, DER-330, ED-22, and ED-20 low-viscosity epoxy oligomers. It was shown that the softening temperature of epoxy oligomers and their mixtures can be controlled by directional variation of molecular weight, molecular-weight distribution, and content of the low-molecular-weight fraction. [ABSTRACT FROM AUTHOR]

Quantum cryptography can provide almost complete security of the data transmitted in optical telecommunication systems by single photons based on the laws of quantum mechanics. The paper presents a brief overview of the element base and experimental investigations in the field of quantum cryptography and data transmission by single photons in atmospheric and optical fiber quantum communication lines. Two experimental setups for the single-photon quantum key distribution in the atmospheric and optical fiber quantum channels are described. The results of the quantum key distribution experiments performed on them are given. [ABSTRACT FROM AUTHOR]

This paper presents a brief review of experimental studies in quantum cryptography and quantum key distribution by single photons in atmospheric and fiber-optic quantum communication channels. Two experimental setups for quantum key distribution developed at the Rzhanov Institute of Semiconductor Physics SB RAS are described. The dependence of the quantum key distribution rate on the average number of photons μ in the laser pulse was studied. For μ > 0.3, there is a discrepancy between theory and experiment. The reasons for this are, first, the nonzero probability of multiphoton pulses occurring in quantum transmission and counted as single photons by single-photon detectors and, second, the rejection of the cases where several single-photon detectors click simultaneously in quantum key sifting because the measurement result is not determined in these cases. [ABSTRACT FROM AUTHOR]

An experimental setup for studying the distribution of a quantum key in a fiber optic communication line designed at the Institute of Semiconductor Physics, Russian Academy of Sciences, Siberian Branch is presented. The structure of a unified control unit for studying the distributed quantum key setup using the BB84 protocol with phase encoding is described. Experimental results on quantum key generation are given. [ABSTRACT FROM AUTHOR]

The dynamics of impedance values of the small and large intestine, parietal peritoneum, and greater omentum was analyzed during different periods of experimental acute intestinal obstruction. The impedance was below the normal, which indicated progressive microcirculatory disorders and necrosis of the intestinal wall. The histomorphological picture of healing of anastomoses created after resection of the intestine with consideration for bioimpedance values and of anastomoses created after resection of the intestine in a priori viable tissues virtually did not differ. [ABSTRACT FROM AUTHOR]

Results are presented from L-2M stellarator experiments on testing a possible method for detection of water microleakages in the cooling system of the first wall and vacuum chamber of ITER. The method consists in the spectroscopic detection of spectral lines of the OH hydroxyl, which forms via the dissociation of water molecules in plasma. Emission in the spectral band of 305-310 nm can be detected even at water leakage rates less than 10 Pa m/s. Chemical reactions between water and boron compounds on the vacuum chamber wall delay the detection of leakages up to ∼2000 s. A similar phenomenon can be expected when a leakage will occur in ITER, where the materials suggested for the first wall (Be, Li) can also chemically react with water. [ABSTRACT FROM AUTHOR]

Results of testing of a possible method for location of water microleakages in the cooling system of the first wall and vacuum chamber of ITER are presented. The method consists in spectroscopic detection of the emission lines of atoms and ions of the Xe additive dissolved in water. These lines are excited when the water with dissolved Xe contacts the plasma. The high electron cyclotron resonance heating (ECRH) power deposited in a relatively small plasma volume in the L-2M stellarator ( P = 0.5 MW, V = 0.24 m, and the specific heating power ∼2 MW/m) makes it possible to achieve plasma parameters close to those in the edge plasma of ITER for different operating modes, including the H-mode with an edge transport barrier. In test experiments, several lines of Xe ions were revealed suitable for detection of xenon in plasma with parameters close to those in the edge plasma of ITER at leakage rates at a level of ∼10 Pa m s and spatial resolution of ∼0.5 cm. [ABSTRACT FROM AUTHOR]

Abstract  Single-stage plasma-arc synthesis of metallo-endofullerences of the types C60Pd, C60Ni, and C60Cr, whose content in a mixture of extracted fullerenes was 0.05 to 0.15 wt %, was performed. The effect of introduction of these metals into the reaction plasma on the total yield of fullerenes and on the fraction composition of the fullerene mixture was studied. The fullerene mixtures were analyzed by mass spectrometry and liquid chromatography. [ABSTRACT FROM AUTHOR]

Subjecting natural gas to multi-stage heating by passing it through the cooled cavities of certain tuyere elements instead of coolant water is technically simple to accomplish and makes it possible to heat the gas to 300°C or more, the exact temperature depending on the amount of gas used. The cost of instituting this technology is an order of magnitude lower than the savings realized by injecting heated natural gas into blast furnaces. The injection of heated natural gas into a blast furnace introduces additional heat into the furnace and makes it possible to use more natural gas in the smelting process without reducing the theoretical combustion temperature. It also increases the value of the coefficient that characterizes the replacement of coke by natural gas, since the gas undergoes more complete combustion in this case. Finally, the injection of heated natural gas results in a more uniform distribution of hydrogen across the furnace and allows fuller use of this element in the smelting operation. [ABSTRACT FROM AUTHOR]

Slags of the required basicity are obtained in blast furnaces at the Lipetsk Metallurgical Plant by adding raw fluxes (limestone and dolomite) to the charge in amounts of 200–300 kg/ton pig iron. Decomposition of the carbonates of calcium and magnesium in these fluxes requires a considerable amount of heat and increases coke consumption in the smelting operation by 45–65 kg/ton pig. To replace the limestone in the charge, the plant uses crushed rock obtained from converter slag. The rock is delivered by the Novolipetsk Metallurgical Combine and is of the 40–70 mm fraction. Most of the economic benefit from using converter slag stems from the replacement of a raw flux (limestone) by lime present in the slag in free form and in the form of compounds-mainly calcium silicates. An equally important factor that affects the cost-effectiveness of using converter slag in the blast-furnace charge is the slag’s 20% iron content. A substantial percentage of the iron in the slag is in the form of FeO and metallic inclusions. [ABSTRACT FROM AUTHOR]

Bakal siderites represent an important source of iron ore that can be used in the production of high-quality pig iron and steel. Their value in this regard stems from the stability of their chemical composition, low content of harmful impurities (sulfur, phosphorus), good reducibility, and good strength in the roasted state. These advantages, combined with the favorable composition of the country rock-which has a basicity (based on CaO + MgO/SiO2) of up to 2.6-makes it possible to classify these siderites as iron-fluxes that can be used effectively in a blast furnace. Roasted siderite concentrate (RSC) can be used efficiently in the blast-furnace charge to make different grades of manganese-bearing foundry iron as long as unfluxed pellets are also employed. On the average, the addition of 10 kg of RSC to the charge per ton of pig iron reduces the consumption of dry skip coke by 0.6–1.5 kg/ton pig and increases furnace productivity by 0.9–2.0 tons/day by decreasing the amount of raw flux needed and increasing the iron content of the fluxed part of the charge. [ABSTRACT FROM AUTHOR]

To reduce the costs of blast-furnace smelting, the Svobodnyi Sokol plant has devised a comprehensive program of organizational-technical measures that include study of ways of reducing coke consumption. To do this, the plant began operating its blast furnaces with schungite when making foundry and conversion pig irons. Using schungite in the charge employed to make foundry iron makes it possible to save a significant (10–15%) amount of coke. The value of the coefficient that characterizes the replacement of coke by schungite varies broadly and can reach 1.0 or more, depending on the grade of iron being made and the furnace operating regime. The same coefficient has a value of 0.57 kg coke/kg schungite when 12–15 kg schungite/ton pig is used to make conversion pig iron. [ABSTRACT FROM AUTHOR]

A method to design tests for the bit-stuck and arbitrary failures of the elements of combinational circuits was proposed. It is based on a graphical description of the orthogonal disjunctive normal forms of the functions realized by the circuit. The graphical description of the circuit by an alternative graph, which was later named the structurally synthesized binary decision diagram graph, carries, along with information about the circuit structure, the orthogonal disjunctive normal forms of the functions of this circuit. The properties of the structurally synthesized binary decision diagram graph allow one, on the one hand, to use it for construction of tests of various circuit failures and, on the other hand, to reduce enumeration at determination of the tests flowing to the use of the orthogonal disjunctive normal forms realized by the circuit and its subcircuits. A full structurally synthesized binary decision diagram graph that features the potential of the structurally synthesized binary decision diagram graph and does not differ so much from the traditional binary decision diagram graphs was introduced to facilitate explanation of the method. The proposed method of test design enables one to determine the entire set of test patterns by determining successively the conjunctions representing these test. [ABSTRACT FROM AUTHOR]

Examines the metallurgical properties of iron-coke briquets made from coke fines and metallic screenings formed in the production of ferrovanadium. Assessment of the feasibility of using the briquets in blast furnaces; Determination of the reproducibility and softenability of the briquets.

Extraction of lanthanide(III) nitrates of ceric subgroup was studied by pure tributylphosphate, 50% solution of trialkylmethylammonium nitrate in toluene and composite materials based on porous Teflon and mentioned extractans in the presence of 1–5 mol/dm3 of sodium nitrate in aqueous phase. Effect of additions of sodium sulfate and chloride to nitrate solutions on distribution parameters of lanthanides(III) was determined. The extraction process can be described with taking into account the formation of [Ln(NO3)3(S) j] ( j = 3, 4) in organic phase. The extraction constants were estimated. It was established, that accounting tributylphosphate concentration in the phase of composite, extraction constants and isotherm shape for systems based on tributylphosphate are identical within the error of determination. In the case of trialkylmethylammonium nitrate those for composite are little greater then for liquid extractant. [ABSTRACT FROM AUTHOR]

Data on the scattering of protons with energies 5 MeV < E < 65 MeV by [sup 90]Zr nuclei and data on the energies of proton particle and hole levels in the A + 1 and A - 1 systems with A = 90 are analyzed within the dispersive optical model. The parameters of the mean proton field for [sup 90]Zr are determined in the energy range -60 MeV < E < +65 MeV. The predicted single-particle features of the levels (root-mean-square radii of orbits, occupation numbers, spread widths, spectroscopic factors, and spectral functions) comply well with experimental data obtained in (d, ³He), (³He, d), (n, d), and (d, n) reactions for levels near the Fermi surface and in (e, e'p) and (p, 2p) reactions for deep levels. [ABSTRACT FROM AUTHOR]

A stochastic–deterministic model is presented for the propagation of a downward-moving leader. Lightning formation is described by a stochastic growth of branching discharge channels which is determined by the electrostatic field. The dynamics of the electric field and of the charge distribution over the lightning structure are calculated deterministically. The model includes the initiation of lightning, a preliminary discharge in a cloud, the propagation of a downward-moving stepped leader toward the earth, and the initiation and upward motion of a return stroke from the earth’s surface. Numerical execution of the model yields a dynamic picture of the development of the downward-moving leader and of the intracloud discharge structure. The effect of the charge density in the cloud and the parameters of the developing channels on the spatial–temporal, current, and charge characteristics of the stepped leader’s propagation are studied. The effect of free-standing structures on the distribution of points on the earth’s surface where lightning strikes is examined. © 1999 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A pyroelectric detector with a time resolution of 3-5 μs and a TEA CO laser have been used in diagnostics of a pulsed molecular beam (a free jet). The kinetic energy distribution of molecules was determined by using time-of-flight measurements both with a laser and without it. A combination of the laser with the pyroelectric detector makes it possible to determine the kinetic energy distribution of molecules in a selected internal state and to measure the energy absorted by the molecules of the beam from a laser pulse. The results obtained for pure SF and the SF seeded in He have been presented and analyzed. The advantages and the disadvantages of the method are being discussed in comparison with other available methods of diagnostics of molecular beams and free jets. [ABSTRACT FROM AUTHOR]

The elements and electrical equipment of open pit mine distribution networks produced by domestic industry require further improvement for the purpose of increasing their reliability, simplicity, and safety in servicing under open pit mine conditions. It is necessary to constantly increase the quality of design of power supply equipment of open pit mines. [ABSTRACT FROM AUTHOR]

The Raman-scattering spectra are studied for six tetrachlorides and tetrabromides of carbon, silicon, titanium, and tin, in the polycrystalline state at various temperatures and in the liquid state. The nature of the complex structure of fundamental oscillation bands is discussed. It is shown that intermolecular interaction, along with the isotope effect, plays an important part in frequency splitting. [ABSTRACT FROM AUTHOR]

The relative effectiveness of glass-reinforced plastics with radial as compared with tangential reinforcement (obtained, for example, by winding) as a material for bodies of revolution subjected to external hydrostatic pressure is examined. [ABSTRACT FROM AUTHOR]