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Carrying out of systematic control of oil and gas pipeline condition is important for provision of normal operability of hydrocarbon transporting system. Implementation of monitoring of pipelines condition using traditional methods requires a lot of material and labour resources. The most important alternative is utilization of unmanned aerial vehicles equipped by lidar. The accident at the pipeline may occur due to such causes as leak, rupture, denture, other causes and unknown ones. The potential accuracy of suggested method for lidar-thermal remote control of route of underground pipeline lay out is analyzed. The possibility for increasing of accuracy of identification of underground pipelines by way of decrease error of identification on two signatures is considered. The chosen signatures are geometrical coordinate at the horizontal plane defined by thermal sensing and vertical coordinate determined by laser measurements. It is determined that by cause of hydromechanical processes occurred in soil within imits of route the shift of pipeline and increase of soil layer level over the pipeline take place. These effects form the total uncertainty of determination of accurate coordinates of pipeline from the board of carrier of laser and thermal sensor. It is shown that performed optimization allows to increase the geometrical accuracy of route determination using suggested method of laser-thermal sensing.

Continuous surface interpolation is an important aspect of spatial analysis. A number of methods are used to interpolate a continuous surface, one of which is the spatial interpolation method with the Inverse Distance Weight (IDW) ratio. The purpose of this article is to develop a method of conditional spatial interpolation for finding such spatial points in the urban zone where the impact of selective accidental aerosol emissions into the city atmosphere is minimal. Conditional spatial interpolation refers to the case when the distances to the interpolated points are set by a certain condition, and it is necessary to determine the interpolated point where the above influence is minimal. In this case, spatial samples or base points used for interpolation are formed when a single powerful aerosol source is exposed to individual channels (distances). It is shown that there is an optimal relationship between the distances from the sampling point to the interpolation point and from the sampling point to the powerful aerosol source, at which the total effect of the powerful source on the interpolated point is minimal.

One of ways to increase accuracy of ground tracking of orbital satellites is high accuracy calibration of network of microtelescopes used for this purpose. To attain high accuracy utilization of stable laser sources of radiation is most expedient. To install such sources the balloon platforms mounted at some height are practiced. But utilization of only one fixed height of all sources for calibration could lead to insufficient value of signal/noise ratio due to unpredictable atmospheric events. At the same time utilization of sources with different spectral characteristics can complicate the required methodic for analysis. Authors suggest utilization of same type lasers and carrying out of calibration using platforms installed at different heights. Nonapparent function of dependence of laser beams divergence on height of balloon installation is considered for analysis. Some integrated limitation is imposed on this function. It is assumed that number of microtelescopes receiving optical radiation of one source linearly depends on height of the source. It is required to find out the optimum type of suggested non-apparent function upon which target functional composed as sum of all calibration signals could reach maximum. Utilization of such property of target functional for checking up of carried out calibration procedure is suggested. Providing for the required type of suggested non-apparent function is technically resolvable task because the beam divergence is controlled parameter and height of platform can be measured with sufficient accuracy.

The paper is devoted to questions on increasing of noise immunity of GPS/INS navigation systems containing GPS and inertial navigation systems. Analysis of effectual methods for digital processing of noisy signals of GPS/INS navigation systems is actual task. At the same time there is another direction of development of GPS navigation systems, based on modification of aerial tract and filtration devices. Different adaptive methods of multi-aerial receipt can be stressed out as an example. As regards the filtration method, there are some additional possibilities for filtration of noisy GPS signals upon presence of a priory or a posteriori data on energy-frequency characteristics of noise signal. The comparative analysis of methods for increasing of noise immunity of integrated GPS/INS navigation systems is carried out. The possibility for optimization of averaged integrated value of modified indicator, named as effective ratio of power of carrier signal on noise power regarding the case of utilization of noise signals pertaining to broad class of noise signals characterized by presence of integrated limitation condition imposed on amplitude-frequency spectrum. The optimization task on increase of averaged integrated parameter indicating the effective value of ratio of power of carrier signal on power of noise signal is formulated. Solution of formulated optimization task make it possible to formulate recommendations for increasing the noise immunity of GPS/INS based navigation systems for some limited class of utilized jamming noise. The methodic to increase noise immunity of GPS targeting systems in condition of jamming noise is suggested., Статья посвящена вопросам повышения помехоустойчивости GPS/INS навигационных систем. Изложен предлагаемый новый способ повышения помехоустойчивости GPS навигационных систем. Приведён сравнительный анализ методов повышения помехоустойчивости интегрированных GPS/Ins систем навигации. В качестве одного из основных показателей отношения сигнал-шум выделен модифицированный показатель, известный под названием эффективное отношение мощности несущего сигнала к мощности шумов. Сформулирована оптимизационная задача повышения среднеинтегрированного показателя «эффективная величина» отношения мощности и несущего сигнала к мощности шумового сигнала. Рассмотрена возможность оптимизации среднеинтегрированной величины рассматриваемого модифицированного показателя в случае применения в качестве шумового сигнала представителя достаточно широкого класса помеховых сигналов, характеризующихся наличием интегрального ограничения на амплитудно-частотный спектр. С учетом исходного целевого функционала и интегрального ограничительного условия, наложенного на шумовые сигналы, составлен целевой функционал безусловной вариационной оптимизации. Решение сформулированной оптимизационной задачи с применением условий уравнения Эйлера-Лагранжа позволило выработать рекомендацию по повышению помехоустойчивости GPS основанных навигационных систем для некоторого ограниченного класса используемых заглушающих помех. На основании полученных результатов составлена методика повышения помехоустойчивости GPS систем наведения в условиях применения заглушающей помехи рассмотренного класса., Статтю присвячено питанням підвищення завадостійкості GPS/INS навігаційних систем, що включають в себе GPS та інерціальні навігаційні пристрої. Пошук ефективних шляхів цифрової обробки зашумлених сигналів навігаційних систем є актуальним завданням, разом з тим, існує також інший напрямок розвитку GPS навігаційних систем, що заснований на удосконаленні антенного тракту і кутів фільтрації. Сюди можна віднести різні адаптивні методи рознесеного прийому. Що стосується методу фільтрації, то тут існують деякі додаткові можливості фільтрації зашумленного GPS сигналу за наявності апріорних або апастеріорних даних про енергочастотні характеристики шумового сигналу. Наведено порівняльний аналіз методів підвищення завадостійкості інтегрованих GPS/Ins систем навігації. Розглянуто можливість оптимізації середньоінтегрірованної величини модифікованого показника, названого ефективним відношенням потужності сигналу до потужності шумів відносно до випадку застосування в якості шумового сигналу представників досить широкого класу сигналів завад та характеризуються наявністю інтегрального обмеження на амплітудно-частотний спектр. Сформульована оптимізаційна задача підвищення средньоінтегрірованого показника «ефективна величина» відношення потужності сигналу до потужності шумового сигналу. Рішення сформульованої оптимізаційної задачі дозволило виробити рекомендації щодо підвищення завадостійкості GPS / INS заснованих навігаційних систем для деякого обмеженого класу використаних перешкод. Запропоновано методику підвищення завадостійкості GPS систем наведення в умовах застосування перешкод.

The assimilation capacity of sea waters is known to be defined as a maximum dynamic volume of such content of pollutants which can be accumulated, destructed, transformed and excluded out of the limits of the ecosystem during a curtain time period if normal condition functioning of the ecosystem is not disturbed. The paper focuses on comparative analysis of assimilation capacity calculated using balance and synoptic methods. Geometrical representation of the compared methods in 3-D space {Т, V, C} is suggested, where T is time interval, V is water mass volume, C is concentration of pollutants. Quantitative correlation between two considered values of assimilation capacity is given. The results obtained are applied for some areas of coastal northern zones of Azerbaijan sector of the Caspian Sea. It is shown that in winter season the value of assimilation capacity calculated using synoptic method is somewhat lower in comparison with the same parameter calculated by balance method and equal to 0.6–0.8 share of the latter. Such a result can be considered as much better in comparison with the known results where the difference reaches one order.

It is well-known that according the Dozier’s method, utilization of integral of Planks function in fusion of signals of two different channels of airborne radiometer makes it possible to compute such components of temperature field within one pixel as temperatures of the object and background. In the paper, the generalization of Dozier method is suggested. The suggested generalization of Dozier’s bispectral method named as biparametric method is applicable for static remote objects. In the suggested biparametric method, the measurements are carried out at the moments t1 and t2. It is assumed that the object temperature reaches quantity T(t1) and T(t2) at these moments. On the bases of operational data of scanning infrared radiometer, the square area of one pixel can be calculated in dependence of distance between object and radiometer. This makes it possible to carry out location of static objects from two basis points using serial single wavelengths measurements of radiation emitted by the sub pixel object.

It is noted that necessity of further increase of accuracy of GPS positioning systems requires de-velopment of more perfect methods to compensate information losses occurred due to residual ionospheric delay by using optimization procedures. According to the conditions of formulated optimization task, the signal/noise ratio in measurements of zenith wet delay depends on the second order ionospheric errors, geographic latitude and day of year. At the same time if we assume that the number of measurements at the fixed geographic site is proportional to geographic latitude and if we accept existence of only two antiphase scenarios for variation of residual ionospheric delay on latitude normed by their specific constant, there should be optimum functional dependence of precipitated water on latitude upon which the quantity of measuring information reaches the maximum. The mathematical grounding of solution of formulated optimization task is given.

A brief review of the use of weighting functions for estimation of the nodes of reference grids based on data from randomly distributed earthbound measurement points is presented. Maximum possible estimates are formulated for these points using a logarithmic modification of the Barnes and Cressman functions.

A well-known method of measuring the optical thickness of clouds with the use of dual-spectrum radiation flux reflected from a subadjacent vegetative cover is generalized. It is shown that the state not only of the clouds but also of the vegetation may be determined. A theorem according to which a known normalized differential cloud index is always less than or equal to the value of a normalized differential vegetation index is proved. Generalized direct and inverse vegetation indices that are most readily adapted in the information sense to the implementation of the proposed generalized method are synthesized.

A method of combined spectroscopy is proposed. A fundamental theorem that demonstrates the extremal nature of the spectral signal generated at the output of remote probe devices in which the method is implemented is formulated and proved. Alternative applications of the proposed method in atmospheric spectroscopy are considered.

The method for multi-level optimization is suggested. The method is based on specific approach to multi-level optimization according which the system should be optimized is sequential levels using relevant optimization criteria. The final solution of the multi-level optimization task is that passed through all levels of optimization.

A new method for calibration of sun photometers based on Bouguer-Beer law is proposed. The developed basic equation of calibration makes it possible to formulate the derivative methods of calibration on the basis of photometric measurements upon optical air masses, the ratio of which is an integer number.