192 research outputs found

    Food security and import substitution: major strategic objectives of contemporary agricultural policy

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    Rural areas and the agricultural sector are currently experiencing a radically new social and economic situation which barely fits the existing national agricultural policy as a long-term instrument for stimulating the agri-food market and government’s support of the agrarian sector and, primarily, agriculture that underlies it. In the age of globalization of national agri-food markets, food supply security based on import substitution can be ensured in a macro-economic environment that favors the development of a competitive agricultural industry. The main factor preventing the industry from developing is the unequal inter-industrial exchange biased against the rural economy. The article proposes the author’s simple tried and tested schema for evaluating how inter-industry pricing relationships and governmental financial support (in the form of subsidies) to agricultural organizations affect their margins. The evaluation leads to the following conclusions: – Given its real contribution to the national economy, the agro-industry is self-sufficient for its own development, i.e. the state objectively has the potential to increase its expenses on the elimination of the negative consequences from an unequal inter-industry exchange; – Federal expenditures on such state support must secure a margin for agricultural goods producers that enables stimuli for workers’ efficiency and an affordable credit system for the technical and technological upgrade of the facilities required for the production of competitive goods; – The issues of competitive growth of agricultural products require solutions primarily on a federal scale. An essential factor of competitive growth of individual types of national food and agricultural raw materials should involve science proven EEU agricultural treaties. The article discusses the major priorities in developing a common agricultural policy in the new integration institution

    Polarization effects in the reaction e++eρ++ρe^++e^-\to \rho^+ +\rho^- and determination of the ρ\rho - meson form factors in the time--like region

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    The electron positron annihilation reaction into four pion production has been studied, through the channel e++eρˉ+ρe^++e^-\to \bar \rho+\rho . The differential (and total) cross sections and various polarization observables for this reaction have been calculated in terms of the electromagnetic form factors of the corresponding γρρ\gamma^*\rho\rho current. The elements of the spin--density matrix of the ρ\rho -meson were also calculated. Numerical estimations have been done, with the help of phenomenological form factors obtained in the space--like region of the momentum transfer squared and analytically extended to the time-like region.Comment: 19 pages, 2 figures, to appear in Phys Rev

    REQUIREMENTS FOR IMAGE QUALITY OF EMERGENCY SPACECRAFTS

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    The paper deals with the method for formation of quality requirements to the images of emergency spacecrafts. The images are obtained by means of remote sensing of near-earth space orbital deployment in the visible range. of electromagnetic radiation. The method is based on a joint taking into account conditions of space survey, characteristics of surveillance equipment, main design features of the observed spacecrafts and orbital inspection tasks. Method. Quality score is the predicted linear resolution image that gives the possibility to create a complete view of pictorial properties of the space image obtained by electro-optical system from the observing satellite. Formulation of requirements to the numerical value of this indicator is proposed to perform based on the properties of remote sensing system, forming images in the conditions of outer space, and the properties of the observed emergency spacecraft: dimensions, platform construction of the satellite, on-board equipment placement. For method implementation the authors have developed a predictive model of requirements to a linear resolution for images of emergency spacecrafts, making it possible to select the intervals of space shooting and get the satellite images required for quality interpretation. Main results. To verify the proposed model functionality we have carried out calculations of the numerical values for the linear resolution of the image, ensuring the successful task of determining the gross structural damage of the spacecrafts and identifying changes in their spatial orientation. As input data were used with dimensions and geometric primitives corresponding to the shape of deemed inspected spacecrafts: Resurs-P", "Canopus-B", "Electro-L". Numerical values of the linear resolution images have been obtained, ensuring the successful task solution for determining the gross structural damage of spacecrafts

    Suppressed absolute negative conductance and generation of high-frequency radiation in semiconductor superlattices

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    We show that space-charge instabilities (electric field domains) in semiconductor superlattices are the attribute of absolute negative conductance induced by small constant and large alternating electric fields. We propose the efficient method for suppression of this destructive phenomenon in order to obtain a generation at microwave and THz frequencies in devices operating at room temperature. We theoretically proved that an unbiased superlattice with a moderate doping subjected to a microwave pump field provides a strong gain at third, fifth, seventh, etc. harmonics of the pump frequency in the conditions of suppressed domains.Comment: 8 pages. Development of cond-mat/0503216 . Version 2: Final version, erratum is include

    A METHOD OF IMAGES CONTRAST ENHANCEMENT UNDER CONDITIONS OF THE EARTH SURVEY FROM SPACE

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    Subject of Research. A method is proposed for the contrast enhancement of the Earth's surface images obtained by airborne optoelectronic complexes of space remote sensing systems. The relevance of the proposed method is confirmed by the results of contrast estimation for space images obtained by modern recording equipment and the results of the contrast calculation for modeled survey conditions. Method. The method is based on the idea of combining different exposure space images. This combination gives the possibility to get the resulting snapshot with an extended dynamic range of brightness. Such picture has a high contrast in the field of dark and light halftones and displays the details of the observed objects better. Main Results. The contrast of the image obtained when selecting the survey parameters by traditional method is estimated. It is concluded that the quality of the images obtained from space is currently limited, since the parameters of the onboard optoelectronic complex do not provide taking into account a larger number of objects with different optical characteristics that are within the capture area of the recording equipment. On the basis of research, an approach to images contrast enhancement is proposed, the essence of which is to expand the dynamic range of brightness and, as a result, to increase the contrast of the images obtained. Practical Relevance. The proposed method for the Earth's remote sensing data processing gives the possibility to obtain images of objects located on the Earth's surface in any light conditions suitable for interpretation. This fact will improve the accuracy of information provision when performing work survey support and mapping area

    Intercomparison of five nets used for mesozooplankton sampling

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    Intercomparison of nets commonly used for mesozooplankton sampling in the Black and Mediterranean seas was attempted within SESAME (Southern European Seas: Assessing and Modelling Ecosystem Changes) project. Five nets were compared: three Juday nets equipped with 150 μm, 180 μm and 200 μm mesh size, Nansen net (100 μm mesh size) and WP2 (200 μm mesh size). Replicated samples were collected at one station in the western Black Sea offshore waters in April 2009. Collected samples were analyzed at species level (except for meroplankton), stages (for copepods) and size length. A decrease of total abundance values was observed with increasing mesh size, due to the significantly higher numbers of animals smaller than 1 mm in the samples obtained by fine mesh size than with coarser nets. Few comparisons were revealed significant for the abundance of animals with 1-2 mm length, while no significance was detected for specimens larger than 2 mm. The above differences resulted in discripancies between nets regarding species and stages composition. Biomass values did not differ significantly between nets, due to the strong contribution to total biomass of the large animals fraction (Calanus euxinus). The smallest and the largest animals revealed high variability between replicates collected by Nansen, Juday- 200 μm and WP2 nets. Correction factors were calculated for the conversion of abundance values between each couple of nets. The detected differences between nets regarding the abundance and biomass, the community taxonomic composition and size structure, as well as the estimated correction factors, provide useful information for the harmonization of data obtained by the above nets in the Black Sea

    Subterahertz chaos generation by coupling a superlattice to a linear resonator

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    We investigate the effects of a linear resonator on the high-frequency dynamics of electrons in devices exhibiting negative differential conductance. We show that the resonator strongly affects both the dc and ac transport characteristics of the device, inducing quasiperiodic and high-frequency chaotic current oscillations. The theoretical findings are confirmed by experimental measurements of a GaAs=AlAs miniband semiconductor superlattice coupled to a linear microstrip resonator. Our results are applicable to other active solid state devices and provide a generic approach for developing modern chaos-based high-frequency technologies including broadband chaotic wireless communication and superfast random-number generation
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