529 research outputs found
TRIANGULAR DECOUPLING THROUGH LINEAR STATE VARIABLE FEEDBACK
The paper studies the problem of triangular decoupling through l.s.v. f. using frequency-domain approaches. The interactor concept and the matrix fraction right description form are used to resolve the questions concerned with this problem and in turn an algorithm is given for triangularization of any right invertible proper system by using l.s.v.f. alone. The paper describes the use of triangular decoupling as an intermediate step for exact decoupling of systems having unstable decoupling zeros
A PRECOMPENSATOR DESIGN TO ACHIEVE DECOUPLING IN THE FREQUENCY DOMAIN
This paper deals with the problem of designing a precompensator by using the frequency domain approach for systems which have weak inherent coupling. A necessary and sufficient new condition for decoupling is given which is the basis of the first algorithm suggested to achieve dynamic decoupling. Another algorithm is presented for the same purpose, by making use of the interactor matrix idea. For each method all the poles of the precompensator can be assigned arbitrarily and the construction does not depend upon the control law used
Perspective varieties of cherry (Cerasus avium Moench.) in Uzbekistan
Uzbekistan annually produces more than 100 thousand tons of cherries and increases the export of cherries to the countries of the world, according to this indicator, the Republic ranks 5th in the world. The article presents data on the production and biological characteristics of sweet cherry varieties. The highest rates for the average weight of one fruit were obtained when growing varieties Melitopolskaya Chernaya (7.8 g), Bakhor (8.2 g) and Russkaya (8.4 g). According to a complex of production and biological characteristics, early fruiting, average fruit weight, yield, promising varieties of sweet cherries Melitopol early (119.3 c/ha) and Russian (112.6 c/ha). When growing these varieties, a high yield of cherry fruits with high quality indicators is ensured
Lack of functional GABA receptors alters Kiss1 , Gnrh1 and Gad1 mRNA expression in the medial basal hypothalamus at postnatal day 4
Background/Aims: Adult mice lacking functional GABAB receptors (GABAB1KO) show altered Gnrh1 and Gad1 expressions in the preoptic area-anterior hypothalamus (POA-AH) and females display disruption of cyclicity and fertility. Here we addressed whether sexual differentiation of the brain and the proper wiring of the GnRH and kisspeptin systems were already disturbed in postnatal day 4 (PND4) GABAB1KO mice. Methods: PND4 wild-type (WT) and GABAB1KO mice of both sexes were sacrificed; tissues were collected to determine mRNA expression (qPCR), amino acids (HPLC), and hormones (RIA and/or IHC). Results: GnRH neuron number (IHC) did not differ among groups in olfactory bulbs or OVLT-POA. Gnrh1 mRNA (qPCR) in POA-AH was similar among groups. Gnrh1 mRNA in medial basal hypothalamus (MBH) was similar in WTs but was increased in GABAB1KO females compared to GABAB1KO males. Hypothalamic GnRH (RIA) was sexually different in WTs (males < females), but this sex difference was lost in GABAB1KOs; the same pattern was observed when analyzing only the MBH, but not in the POA-AH. Arcuate nucleus Kiss1 mRNA (micropunch-qPCR) was higher in WT females than in WT males and GABAB1KO females. Gad1 mRNA in MBH was increased in GABAB1KO females compared to GABAB1KO males. Serum LH and gonadal estradiol content were also increased in GABAB1KOs. Conclusion: We demonstrate that GABABRs participate in the sexual differentiation of the ARC/MBH, because sex differences in several reproductive genes, such as Gad1, Kiss1 and Gnrh1, are critically disturbed in GABAB1KO mice at PND4, probably altering the organization and development of neural circuits governing the reproductive axis. (c) 2013 S. Karger AG, Basel
Survey on solar X-ray flares and associated coherent radio emissions
The radio emission during 201 X-ray selected solar flares was surveyed from
100 MHz to 4 GHz with the Phoenix-2 spectrometer of ETH Zurich. The selection
includes all RHESSI flares larger than C5.0 jointly observed from launch until
June 30, 2003. Detailed association rates of radio emission during X-ray flares
are reported. In the decimeter wavelength range, type III bursts and the
genuinely decimetric emissions (pulsations, continua, and narrowband spikes)
were found equally frequently. Both occur predominantly in the peak phase of
hard X-ray (HXR) emission, but are less in tune with HXRs than the
high-frequency continuum exceeding 4 GHz, attributed to gyrosynchrotron
radiation. In 10% of the HXR flares, an intense radiation of the above genuine
decimetric types followed in the decay phase or later. Classic meter-wave type
III bursts are associated in 33% of all HXR flares, but only in 4% they are the
exclusive radio emission. Noise storms were the only radio emission in 5% of
the HXR flares, some of them with extended duration. Despite the spatial
association (same active region), the noise storm variations are found to be
only loosely correlated in time with the X-ray flux. In a surprising 17% of the
HXR flares, no coherent radio emission was found in the extremely broad band
surveyed. The association but loose correlation between HXR and coherent radio
emission is interpreted by multiple reconnection sites connected by common
field lines.Comment: Solar Physics, in pres
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