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91.
Reconfigurable arrays by phase-only control 总被引:3,自引:0,他引:3
Bucci O.M. Mazzarella G. Panariello G. 《Antennas and Propagation, IEEE Transactions on》1991,39(7):919-925
Due to space or cost reasons, a single array antenna can be required to radiate more than one pattern, each pattern being selected by an electronic control, in which only the phase can be modified. A synthesis method for such a problem that is able to determine both the common amplitude and the various phases in an integrated way is presented. Moreover, the approach is flexible enough to take into account additional constraints and allows an efficient implementation. Some test cases showing the effectiveness of the method are presented 相似文献
92.
F. Seiffert R. Schwengner G. Winter L. Funke W. Lieberz R. Reinhardt K. P. Schmittgen D. Weil R. Wrzal K. O. Zell P. von Brentano 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):141-153
Excited states of73Se have been investigated up to spin, 21/2 using techniques of in-beamγ-ray spectroscopy in connection with the70Ge(α, n) reaction. Mean lifetimes of 12 levels have been determined applying Doppler-shift andγ-RF-methods. Five different bands have been identified that reflect a variety of different excitation modes. The decoupled 9/2+ band is likely to correspond to an oblate deformation while the 5/2+ band is interpreted as a strongly coupled prolate band built on the Nilsson configuration [422] 5/2+. The 3/2? band is a strongly coupled band built on the [301] 3/2} configuration.Nuclear reactions:70Ge(α,n),E=14, 16, 18, 19, 20MeV; measuredE γ,I γ,σ(E γ,θ),γγ-coin, linear polarization, DSA,γ(t).75Se deduced levels,I, π, τ, δ(E2/M1), B(σλ). Enriched targets, Ge detectors. 相似文献
93.
O. I. Mokhov 《Functional Analysis and Its Applications》1991,25(2):136-137
Scientific Industrial Association, All-Union Scientific Research Institute of Physicotechnical and Radiotechnical Measurements. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 25, No. 2, pp. 65–67, April–June, 1991. 相似文献
94.
O O Adedeji 《The Analyst》1992,117(11):1753-1756
Enzymic methods were employed to analyse the structure of the non-dialysable urinary glucoconjugates of ten healthy males. The excretion of the urinary glucoconjugates was determined from the glucosyl:galactosyl ratio after acid hydrolysis, and a mean value of 0.27 was obtained. The results of the specific actions of alpha- and beta-glucosidases showed that the non-dialysable urinary glucoconjugates contain a branched alpha-glucan fraction with 1,4- and 1,6-glucosidic bonds, and a beta-glucan fraction containing 1,4-glucosidic bonds. 相似文献
95.
In reliability evaluation that uses minimal cut-set theory, the deduction of minimal cut-set orders is crucial and depends on all the identified minimal paths associated with the load point whose reliability indices are desired. An input-reduction programming technique that automates this deduction is presented. The technique can be applied to a network of any configuration and finds its greatest application in complex networks with multiple inputs. The power-system structure in the form of power-arms (termination busbars, branch and protective device) is the only initial input data needed. The results obtained, in terms of minimal paths and minimal cut-set orders for all the load points, using the program on a sample power system compare well with the existing results. The program is compact, modular, and easy to use and can be applied to any complex system to generate minimal cut-sets of the desired orders 相似文献
96.
In vitro and in vivo proton T1 data are reported that demonstrate that the paramagnetic copper-D-penicillamine complex can be applied as a potential contrast agent to magnetic resonance imaging. 相似文献
97.
Faced with multiple electronic devices, service providers, and ISPs, tomorrow's mobile users might find it challenging to identify available services and acquire the rights to use them. The authors tackle this problem, combining the acquisition of role-based credentials with servicediscovery. 相似文献
98.
99.
S. A. Chernyak O. V. Shekhter N. L. Sergovskaya Yu. S. Tsizin 《Chemistry of Heterocyclic Compounds》1992,28(7):832-834
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 994–996, July, 1992. 相似文献
100.
Dumbrajs O. Nuisnovich G.S. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1992,20(4):452-457
A theory is presented which describes the dependence of the multimode operation of a gyrotron on the modulation and beam voltages. Nonlinear nonstationary processes are considered. An approximate start-up scenario of a gyrotron is determined which makes it possible to achieve single-mode excitation and high-efficiency operation in a desired mode, as well as to switch the tube to a similar operation in other modes 相似文献