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The authors present results of scientific research and practical application of equipment and technologies for hydropulse stimulation of the formation in order to increase the productivity of producing wells and susceptibility of injection wells. It is shown that in order to improve the filtration characteristics of the near-wellbore zone, it is proposed to use a method of pulsed action with various vibration sources. As a result a network of artificial and natural cracks is formed and develops in the near-wellbore zone of the formation. The most effective and most common sources of low-frequency vibrations in the Republican Unitary Enterprise “Production Association “Belorusneft” are pulsators of valve, cavitation and rotary types. Valve-type pulsators allow to create low- frequency pulses of 0.5–20 Hz with an amplitude of up to 15 MPa and constructively regulate the onset of the pulsation regime and the amplitude of oscillations in the near-wellbore and remote zones of the formation. The cavitation pulsator ensures the creation of amplitude pressure oscillations in the low-frequency range. A rotary pulsator makes it possible to generate a pulsed circular movement of a well fluid or a chemical reagent in the perforation zone. The considered hydraulic pulse technologies using equipment developed at BelNIPIneft have shown their effectiveness, expressed in the resulting additional oil production, and manufacturability of application.

A unique type of oscillation modes has recently been identified in gamma Doradus variables. These low-frequency modes are called Rossby modes (or r modes) because they consist of Rossby waves in each spherical layer. These waves are characterised by toroidal motions that are restored by the latitudinal variation in the Coriolis force. The horizontal oscillations are weakly coupled in the radial direction. We show that these modes can be used to probe the interior of the stars. The method of thenu - root Delta nunu -Deltanudiagram, which has originally been developed to analyse another type of modes, Kelvin g-modes (or prograde sectoral g-modes), is extended to take Rossby modes into account. We first show based on a theoretical model and then on two stars, KIC 3240967 and KIC 12066947, that the method can be adapted to Rossby modes straightforwardly. In addition, we demonstrate that simultaneous analysis of Kelvin and Rossby modes results in (1) smaller uncertainties in the internal rotation rate and the characteristic period of gravity modes, and (2) a substantial reduction of the correlation between the estimates of the two parameters.

Het is geen magnetron, de door het Schalkwijkse bedrijf OMVE en het Wageningse onderzoeksinstituut Food & Biobased Research ontwikkelde Nutri-Pulse. Maar in de nabije toekomst vervangt het apparaat in onze keukens misschien wel die magnetron. Een uitvoering van de Nutri-Pulse is al op de markt. Niet voor consumenten, maar voor grootkeukens.

Het is geen magnetron, de door het Schalkwijkse bedrijf OMVE en het Wageningse onderzoeksinstituut Food & Biobased Research ontwikkelde Nutri-Pulse. Maar in de nabije toekomst vervangt het apparaat in onze keukens misschien wel die magnetron. Een uitvoering van de Nutri-Pulse is al op de markt. Niet voor consumenten, maar voor grootkeukens.

International audience; Context: We present the CoRoT light curve of the beta Cep star HD 180642, assembled during the first long run of the space mission, as well as archival single-band photometry. Aims: Our goal is to analyse the detailed behaviour present in the light curve and interpret it in terms of excited-mode frequencies. Methods: After describing the noise properties in detail, we use various time series analyses and fitting techniques to model the CoRoT light curve, for various physical assumptions. We apply statistical goodness-of-fit criteria that allow us to select the most appropriate physical model fit to the data. Results: We conclude that the light-curve model based on nonlinear resonant frequency and phase locking provides the best representation of the data. Interpretation of the residuals is dependent on the chosen physical model used to prewhiten the data. Conclusions: Our observational results constitute a fruitful starting point for detailed seismic stellar modelling of this large-amplitude and evolved beta Cep star.

Bij het melken van een koe gaat het erom de aanwezige melk vlot af te voeren, waarbij de speen niet te zwaar belast mag worden. Om aan beide doelen tegemoet te komen zijn eisen gesteld aan de lengte van de zuig- en rustfase in een pulsatiecyclus. Een pulsatie-instelling waarbij snel wordt gemolken, hoeft niet te leiden tot extra speenzwelling.

Bij het melken van een koe gaat het erom de aanwezige melk vlot af te voeren, waarbij de speen niet te zwaar belast mag worden. Om aan beide doelen tegemoet te komen zijn eisen gesteld aan de lengte van de zuig- en rustfase in een pulsatiecyclus. Een pulsatie-instelling waarbij snel wordt gemolken, hoeft niet te leiden tot extra speenzwelling.