Geodesic
The orthoprojection widths of some classes of periodic functions of two variables with a given majorant of the mixed moduli of continuity
Izvestiya. Mathematics, Tome 64 (2000) no. 1, pp. 121-141 
N. N. Pustovoitov. The orthoprojection widths of some classes of periodic functions of two variables with a given majorant of the mixed moduli of continuity. Izvestiya. Mathematics, Tome 64 (2000) no. 1, pp. 121-141. http://geodesic.mathdoc.fr/item/IM2_2000_64_1_a3/
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Voir la notice de l'article provenant de la source Math-Net.Ru

This paper deals with the orthoprojection widths of classes of periodic functions of two variables with a given majorant of the mixed moduli of continuity of order $l$ that contains logarithmic factors as well as powers. In several cases we find the exact orders of the orthoprojection widths of these classes of functions.

[1] Temlyakov V. N., “Poperechniki nekotorykh klassov funktsii neskolkikh peremennykh”, DAN SSSR, 267:2 (1982), 314–317 | MR

[2] Temlyakov V. N., “Priblizhenie funktsii s ogranichennoi smeshannoi proizvodnoi”, Tr. MIAN SSSR, 178, Nauka, M., 1986, 3–113 | MR | Zbl

[3] Temlyakov V. N., “Otsenki asimptoticheskikh kharakteristik klassov funktsii s ogranichennoi smeshannoi proizvodnoi ili raznostyu”, Tr. MIAN SSSR, 189, Nauka, M., 1989, 138–168 | MR

[4] Andrianov A. V., Temlyakov V. N., “O dvukh metodakh rasprostraneniya svoistv sistem funktsii ot odnoi peremennoi na ikh tenzornoe proizvedenie”, Tr. MIRAN, 219, 1997, 32–43 | MR | Zbl

[5] Din Zung, “Priblizhenie funktsii mnogikh peremennykh na tore trigonometricheskimi polinomami”, Matem. sb., 131(173):2(10) (1986), 251–271 | MR | Zbl

[6] Galeev E. M., “Poryadki ortoproektsionnykh poperechnikov klassov periodicheskikh funktsii odnoi i neskolkikh peremennykh”, Matem. zametki, 43:2 (1988), 197–211 | MR

[7] Telyakovskii S. A., “Nekotorye otsenki dlya trigonometricheskikh ryadov s kvazivypuklymi koeffitsientami”, Matem. sb., 63(105):3 (1964), 426–444 | MR

[8] Bari N. K., Stechkin S. B., “Nailuchshie priblizheniya i differentsialnye svoistva dvukh sopryazhennykh funktsii”, Tr. Mosk. matem. ob-va, 5, 1956, 483–522 | MR | Zbl

[9] Pustovoitov N. N., “Predstavlenie i priblizhenie periodicheskikh funktsii mnogikh peremennykh s zadannym smeshannym modulem nepreryvnosti”, Analysis Mathematica, 20 (1994), 35–48 | DOI | MR | Zbl