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The article discusses the problems of activation of the surface of the leather tissue by laser exposure, changes in the morphology of the surface of the leather tissue during laser processing, and subsequent covering dyeing of the leather. It is shown that laser treatment changes the structure of the surface of the leather tissue, the bundles of collagen fibers are split, the structure becomes loose, which increases the diffusion of the coating dye reagents, and their reactivity increases without chemical modification. In the process of grinding leather fabric, it is finely cleaned which improves adhesion of the coating paint to the surface of the leather fabric, which improves the quality of leather fabric products. It was shown that laser exposure under the conditions found (pulses with an interval of 3 μs, a duration of 10 ns) does not cause destruction and configuration changes in collagen.

A new type corn-thresher was developed and tested for farms in Uzbekistan. Unlike to the existent threshers, this corn-thresher peels the husks of corn-cobs and threshes the kernel. At first parameters of the peeler-bars were researched theoretically, then three types of peeler bars were installed symmetrically on the surface of rotor of the corn-thresher and compared experimentally. The corn-thresher works qualitatively and it requires least metal and energy. The weight of corn-thresher is just 350 kg, consumes power amount is 5 KW and the work performance of the thresher in the pure time is 4600 kg/hour. During the theoretical research, the results were determined that, width of the peeler-bar should be bigger or equal than 4.8 cm (b p ≥ 4.8 cm). Also, the distance between peeler-bar and concave should be equal to 38 mm (S c = 38). While we researched experimentally the types of peeler bars, three type of them, namely straight tooth, sloped tooth and fluted bar were tested. Their surface was compared between 36-44 mm distance of peeler-bar and concave. When the distance between sloped tooth peeler-bar and concave was 38-40 mm, we achieved to peeling well the husk of corn-cob, threshing better the kernels than other peelers, the most important was that any grain had not damaged when we analyzed results.

PurposeThe purpose of this paper is to make performance improvements and timely critical execution enhancements for operational flight program (OFP). The OFP is core software of autonomous control system of small unmanned helicopter.Design/methodology/approachIn order to meet the time constraints and enhance control application performance, two major improvements were done at real‐time operating system (RTOS) kernel. They are thread scheduling algorithm and lock‐free thread message communication mechanism. Both of them have a direct relationship with system efficiency and indirect relationship with helicopter control application execution stability through improved deadline keeping characteristics.FindingsIn this paper, the suitability of earliest deadline first (EDF) scheduling algorithm and non‐blocking buffer (NBB) mechanism are illustrated with experimental and practical applications. Results of this work show that EDF contributes around 15 per cent finer‐timely execution and NBB enhances kernel's responsiveness around 35 per cent with respect to the number of thread context switch and CPU utilization. These apply for OFP implemented over embedded configurable operating system (eCos) RTOS on x86 architecture‐based board.Practical implicationsThis paper illustrates an applicability of deadline‐based real‐time scheduling algorithm and lock‐free kernel communication mechanism for performance enhancement and timely critical execution of autonomous unmanned aerial vehicle control system.Originality/valueThis paper illustrates a novel approach to extend RTOS kernel modules based on unmanned aerial vehicle control application execution scenario. Lock‐free thread communication mechanism is implemented, and tested for applicability at RTOS. Relationship between UAV physical and computation modules are clearly illustrated via an appropriate unified modelling language (UML) collaboration and state diagrams. As experimental tests are conducted not only for a particular application, but also for various producer/consumer scenarios, these adequately demonstrate the applicability of extended kernel modules for general use.

The results of a study of nonlinear refraction and nonlinear absorption at a wavelength of 532 nm in an LGO (Li2Ge2O15) crystal by Z-scan methods are presented. It is shown that the nonlinear refraction is caused by self-focusing of the laser radiation, whereas the nonlinear absorption is three-photon in nature. The possibility of using an LGO crystal for producing the optical limiting of laser radiation of picosecond duration is demonstrated.

The nonlinear optical characteristics of silver aggregates in a polymeric matrix are studied by the Z-scan method at the wavelength λ = 1064 nm. The nonlinear refractive index and the third-order nonlinear susceptibility of a sample with silver aggregates are measured. It is shown that the nonlinear refraction in the sample is related to the Kerr effect. The character of the nonlinear absorption process is discussed.

The processes of nonlinear refraction and nonlinear absorption are studied in the photorefractive Bi12SiO20 (BSO) and Bi12GeO20 (BGO) crystals at a wavelength of a picosecond Nd:YAG laser of 1064 nm. The nonlinear refraction in the crystals is shown to be related to the Kerr effect, and the nonlinear absorption at this wavelength, to three-photon absorption. The three-photon absorption coefficients of the BSO and BGO crystals are equal, respectively, to (2.5±0.8) ×10−20 and (4.4±1.3) ×10−20 cm3W−2.

Overexpression of a dominant-negative truncated Kv1.1 (Kv1DN) polypeptide in the mouse heart resulted in marked attenuation of a 4-aminopyridine (4-AP)-sensitive current, IK,slow1. We used recombinant adeno-associated virus (rAAV) as a vector for direct delivery of Kv1.5 into the mouse myocardium in order to normalize the action potential duration (APD) 6 months after injection. The injection of rAAV-Kv1.5 reconstituted the 4-AP-sensitive outward potassium currents, shortened the APD, and eliminated spontaneous early afterdepolarizations. Immunoblots detected the FL-Kv1.5 polypeptides only in rAAV-Kv1.5-infected hearts. These data demonstrate long-term expression of 4-AP-sensitive potassium currents in ventricular myocytes by gene transfer using rAAV vector encodes Kv1.5.

The efficiency of generation of the third harmonic (THG) of Nd:YAlO3 laser radiation in barium vapor is analyzed. The influence of the following factors is taken into consideration: the interference of transformed radiation in the case of THG via two channels ω+ω+ω→3ω and 2ω+2ω−ω →3ω, the Kerr effect, two-photon absorption, and the relationship between the energies of the first and second harmonics of radiation. It is shown that the Kerr effect, on the one hand, violates the phase matching conditions in the direct channel but, on the other hand, increases the conversion efficiency due to a defocusing action of the medium, which reduces the influence of the phase detuning between the pumping waves on the process of harmonic generation in the case of generation of difference frequencies. At the same time, the two-photon absorption leads to the depletion of one of the interacting waves (in this case, the second harmonic) and to the prevalence of third harmonic generation through the direct channel.

Optical limiting of pico-and nanosecond pulsed radiation of a Nd:YAG laser (λ=1064 and 532 nm) is studied in solutions of fullerenes (C60 and C70), semiconductor crystals and films (GaAs, As2S3, As20S80, 2As2S3/As2Se3, and 3As2S3/As2Se3), and colloidal solutions of metals (Au, Ag, Pt, and Cu). The effect of the particle aggregation in silver solutions on the optical limiting is considered. Optical limiting mechanisms, specifically, reverse saturable absorption, two-photon absorption, and self-action effects, are discussed. Nonlinear absorption coefficients of the studied materials are measured.

Nonlinear optical parameters (nonlinear refractive indices and nonlinear absorption coefficients) of solutions of polyvinylpyrrolidone doped by cobalt to various concentrations are measured at the lasing and second-harmonic wavelengths of a picosecond Nd:YAG laser (λ=1064 and 532 nm, respectively, and τ=35 ps). Data on optical limitation in these solutions are presented. The absence of nonlinear absorption in the IR spectral range and its significant effect in the visible range are demonstrated. Optical limitation at a wavelength of 1064 nm is related to defocusing, whereas at 532 nm, this effect is caused by two-photon absorption and partially by inverse saturated absorption and defocusing. Nonlinear optical parameters of metal-polymer complexes are reported.

We present the characterization of nonlinear optical parameters of chalcogenide films (As2 S3, As20 S80, 2As2 S3/As2 Se3, 3As2 S3/As2 Se3). We have measured their nonlinear refractive indices and two-photon absorption coefficients using the Z-scan method at the wavelengths of picosecond Nd:YAG laser radiation (1064 nm and 532 nm). We have analysed numerically the optical limiting of chalcogenide films due to the Kerr-induced nonlinearities, and in the case of 2As2 S3/As2 Se3 we found 12.5-fold limiting. We present the experimental results on optical limiting due to two-photon absorption. We obtained 25-fold optical limiting in the case of As2 S3. We discuss the variations of nonlinear optical properties of chalcogenide films.

Results of theoretical studies of laser and Kerr nonlinear susceptibilities of vapors and solutions of organic dyes using a series of polycyclic arenes as an example are presented. Nonlinear susceptibilities of the third χ(3) (−3ω; ω, ω, ω) and the fifth χ(5) (−3ω; ω, ω, ω, ω, −ω) orders of a series of organic dyes responsible for third harmonic generation of Nd:YAG laser radiation are calculated within the context of the free electron model. Results of calculations of their Kerr third-order nonlinear susceptibilities χ(3) (−ω; ω, −ω, ω) and non-linear refractive indices n 2 are presented. The calculation results are compared with experimental data on third harmonic generation in naphthalene vapors and with χ(3) (−ω; ω, −ω, ω) as well as n 2 of paraterphenyl and naphthalene solutions.

The relation between the degree of aggregation of silver hydrosols and their nonlinear refractive index n2 is studied experimentally. It is found that the sign of n2 at a wavelength of 1.064 μm changes with increasing the aggregation degree, which corresponds to the replacing of self-focusing by self-defocusing. The observed effects are explained based on the analysis of a change in nonlinear dispersion of the medium, taking into account the interaction between phases and the photochromic effects, which are typical for colloidal structures with fractal geometry. It is shown that the change in the sign of the nonlinear refractive index of hydrosols upon irradiation by laser pulses of duration of less than 10-7 s is caused by the perturbation of resonances of silver and water and by the competition between Kerr nonlinear polarisations involving these resonances.

The investigations of the nonlinear optical parameters of Au, Ag, Pt and Cu colloidal solutions using the Z-scan method and third-harmonic generation (THG) are presented. The nonlinear refractive indices, nonlinear absorption coefficients and Kerr-induced nonlinear susceptibilities (χ(3)(-ω;ω,-ω,ω)) of these solutions on the wavelengths of picosecond and nanosecond Nd:YAG laser radiation (λ = 1064 nm) and its second harmonic (λ = 532 nm) have been measured. A tenfold increase of nonlinear susceptibilities on the wavelength of 532 nm in comparison with λ = 1064 nm is shown for these colloidal metals. The application of colloidal metals as optical limiters of picosecond and nanosecond radiation (λ = 1064 nm and 532 nm) was studied. The influence of aggregation of colloidal clusters on optical limiting in these media was considered. It was shown that the appearance of the long-wave wing of absorption at the final stages of aggregation led to the nonlinear absorption of picosecond pulses. The investigations of the THG of picosecond Nd:YAG laser radiation in colloidal metals (Pt and Cu) are presented. THG efficiency was found to be 7×10-7 for colloidal platinum. Nonlinear susceptibilities χ(3)(-3ω;ω,ω,ω) of colloidal platinum and copper were measured to be (1.5±0.75)×10-14 esu and (1±0.5)×10-14 esu, respectively.

Results of the study of nonlinear optical parameters of colloidal solutions of silver, gold, platinum, and copper by the Z-scan method are presented. The nonlinear refractive indices of these solutions at the wavelength of the Nd:YAG laser (λ=1064 nm) and its second harmonic (λ=532 nm) were measured. The two-photon absorption of these solutions and their nonlinear susceptibilities were studied.

The nonlinear optical parameters of colloidal metal solutions, semiconductor chalcogenide films, dye vapors and solutions, and fullerene-doped polyimide films and solutions are investigated by Z-scan method and third harmonic generation (THG). We measure nonlinear refractive indices, nonlinear susceptibilities and nonlinear absorption coefficients of such materials at the wavelengths of Nd:YAG laser radiation and its second harmonic ( u; = 1064 nm and 532 nm, ‰ = 35 ps). We study the optical limiting of picosecond and nanosecond radiation in these media. We show that the appearance of long-wave wing of absorption at the final stages of colloidal metals aggregation leads to the nonlinear absorption of picosecond pulses. THG studies of picosecond Nd:YAG laser radiation in colloidal metals, fullerenes and dye vapors are presented. We measure their nonlinear optical susceptibilities h; (3) ( m; 3 y , y , y , y ) and discuss the influence of self-action processes on THG in these media.

Investigations of nonlinear optical parameters of C 60 and C 70 films and solutions by Z -scan method are presented. Nonlinear refractive indices on the wavelength of Nd:YAG laser radiation ( λ =1064 nm) have been measured. Two-photon absorption and nonlinear susceptibilities of fullerene-doped films and solutions have been studied.

Investigations of nonlinear optical frequency conversion of Nd:YAG laser radiation in naphthalene vapors are presented. The third harmonic generation (THG) caused by difference frequency generation in six-photon process has been studied. Phase-matching temperature for naphthalene vapor was found to be 170°C, at which synchronous conversion of pump radiation to the third harmonic was carried out. The THG conversion efficiency varied within 10 −10 –10 −8 depending on pump intensity and cell temperature. Third- and fifth-order nonlinear optical susceptibilities were calculated and compared with the experimentally measured fifth-order susceptibility of naphthalene vapors.

The third-order nonlinear susceptibilities of the aqueous solutions of polyvinylpirrolidone doped with iron and zinc were studied by the method of third-harmonic generation with 1064-nm Nd:YAG laser radiation. The efficiencies of transformation into the third harmonic in these metallic complexes were 8×10−7 and 5×10−7, respectively. To determine the role of the Kerr effect in the transformation process, the nonlinear refractive index of the iron-doped polyvinylpirrolidone solution was measured by the Z-scan method and a value of n2=−6.7×10−13 cgs unit was obtained.

The results of third-order nonlinear susceptibilities studies of Fe- and Zn-doped polyvinylpyrrolidone (PVP) aqueous solution in processes of third harmonic generation of Nd:YAG laser radiation are presented. Nonlinear susceptibilities of PVP:Fe and PVP:Zn were calculated to be 5×10-13 esu and 3×10-13 esu respectively. Third harmonic conversion efficiencies in these metallocomplexes were measured to be 8×10-7 and 5×10-7 respectively. The Z-scan method was applied to determine Kerr effect influence on frequency conversion process. The value of nonlinear refractive index of PVP:Fe at the wavelength of λ = 1064 nm was measured to be n2 = - 6.7×10-13 esu.

The process of optical limitation in the aggregated gold hydrosol was studied, which is caused by the nonlinear absorption of the Nd : YAG laser radiation (wavelength λ = 1064 nm) with a picosecond pulse duration. The nonlinear absorption coefficient of gold hydrosol measured by the Z-scanning method is equal to 8.6 × 10–12 cm W–1.

The phenomenon of nonlinear optical conversion of a YAG:Nd laser radiation frequency from IR to UV spectral range in naphthalene vapors was studied. The optimum temperature of naphthalene vapors (170°C) was found at which the pumping radiation is synchronously converted into the third harmonic emission. A mechanism of the third harmonic generation is proposed based on the difference frequency generation in a six-photon process. The efficiency of conversion to the third harmonic generation varied within 10−10–10−8, depending on the pumping intensity and cell temperature. Nonlinear optical characteristics of naphthalene vapors were calculated for the generation using nonlinearities of the third and fifth order.

In this paper, we introduce the target scenario of our HELISCOPE project with the emphasis on the four modes for flying-camera task. We also explain the control points that are considered as the interfaces where the on-flight embedded software and mechanical implementation of the unmanned helicopter are contacted for the autopilot necessarily used in performing such as various modes of flying-camera tasks. Being related to real-time issues, we are developing a real-time S/W platform based on TMO (time-triggered and message-triggered object) scheme. We, in this paper, explain the clues in becoming to use the TMO mode with the survey of other on-flight real-time S/W platform researches.

We evaluated the molestus form of Culex pipiens pipiens (L.) (hereafter referred to as "molestus") captured near Tashkent, Uzbekistan, for their ability to transmit Japanese encephalitis (family Flaviviridae, genus Flavivirus, JEV) and West Nile (family Flaviviridae, genus Flavivirus, WNV) viruses under laboratory conditions. These molestus were highly competent laboratory vectors of WNV, with infection and dissemination rates of 96 and 81%, respectively. Approximately 75% of female molestus that fed after development of a disseminated infection transmitted virus by bite. Therefore, approximately 60% of those molestus taking a second bloodmeal between 16 and 25 d after an infectious bloodmeal would be expected to transmit WNV by bite. In contrast, these molestus were less efficient vectors of JEV, with infection and dissemination rates of 51 and 25%, respectively. In addition, only 33% of individuals with a disseminated infection transmitted JEV by bite, indicating a significant salivary gland barrier. Therefore, only approximately 8% of orally exposed individuals would be expected to transmit JEV by bite if they took a second bloodmeal 16-25 d later. These data indicate that the molestus form of Cx. p. pipiens should be considered a potentially important vector of WNV in Uzbekistan and may become involved in the transmission of JEV, should this virus be introduced into Uzbekistan.

Investigations of nonlinear optical parameters of AU, Ag, Pt and Cu colloidal solutions by Z-scan method are presented. Nonlinear refractive indices of these solutions on the wavelength of Nd:YAG laser radiation and its second harmonic have been measured. Two-photon absorption and nonlinear susceptibilities of these solutions have been studied.

Parametric lasing in the vacuum-ultraviolet range was investigated experimentally in barium vapor. Picosecond YAlO3:Nd3+ laser pulses were frequency-converted to the ~ 180-nm range with an efficiency of 0.7%. The dependences of the conversion efficiency on the buffer gas pressure and on the position of the constriction of the pump radiation beam were studied. The principal factor limiting the efficiency under resonance conditions was found to be the Stark effect.

Investigations of nonlinear-optical frequency conversion of Nd:YAG laser radiation in naphthalene vapors are presented. Third harmonic generation caused by difference frequency generation in six-photon process was offered. Optimum temperature for naphthalene vapor was found to be 170 degree(s)C, at which the synchronous conversion of pump radiation to the third harmonic radiation was carried out. Third harmonic generation conversion efficiency varied within the 10 -10 depending on pump intensity and cell temperature. Third-and fifth-order nonlinear-optical susceptibilities of naphthalene vapors were calculated.

Nonlinear refraction, nonlinear absorption, and optical limitation are studied in Bi12SiO20 (BSO) and Bi12GeO20(BGO) crystals at the 532-nm emission wavelength of a picosecond Nd : YAG laser.

Nonlinear optical parameters of polyimide and toluene films containing fullerenes C60 and C70 are studied by the method of Z-scan. The nonlinear refractive indices of these structures are measured at the emission wavelength of a Nd:YAG laser at 1064 nm. The two-photon absorption and nonlinear susceptibility of solutions and films containing fullerenes are studied.