Đang chuẩn bị liên kết để tải về tài liệu:
Mechanical Engineers Reference Book 12E Episode 17
Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Tham khảo tài liệu 'mechanical engineers reference book 12e episode 17', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Series and transforms 17 13 Figure 17.15 Sawtooth wave Basic formulae J t exp j2ir z d u j 5 u z exp -ịĨTTfl dt Change of sign and complex conjugates -z 5 - u z - Time and frequency shifts r and constant n z - t 5 t exp -j2Tr i- exp i2m z u z U f - d Scaling T constant u z 7 TU jT Products and convolutions zz Z v z U f V f uự v t Differentiation 0 j2rr G -j27rZzz z U f du t oi lda 5 d U f a da Integration 1 0 0 a and b real constants Figure 17.16 Pulse wave i r dr U f l lTTf 17.3.11 Square wave 4 X . sin 2n 1 Z 17.3.12 Triangular wave 8 . . 4. sin 2n - l wz . A s -J - TT 2n - 1 17.3.13 Sawtooth wave 2 X t .sin n ửt 77 n n 17.3.14 Pulse wave T 2t x- sin rz UT 7 2mrt M cos t i I rĩTĩT i i 17.3.15 Fourier transforms Among other applications these are used for converting from the time domain to the frequency domain. Interchange of functions t Z u -f Dirac delta functions 5 z 5 1 exp j2-rr 0 5 8Ự - fo Rect z unit length unit amplitude pulse centred on z 0 rect z i sin irf irf Gaussian distribution exp -7TZ2 exp -7r 2 Repeated and impulse delta function sampled waveforms u t -nT Í T UỢ ị ÔỰ - n T U f y 5 z - nT 5 1 7 y - n T -7- - X Parseval s lemma j u z v z dz j u z 2dz J Wf 2df 17.3.16 Laplace transforms vt v z exp -5Z Jo 17 14 Engineering mathematics Function Transform Remarks e 1 X a sin ù t i s2 bl2 cos bit s s2 bl2 sinh bit i 2 . .2 s Ù cosh bit s s2 I 2 t n lsn Hự i s H t - r - exp st s Heaviside step function x - f H t - r exp -sr x s Shift in t S t - r expt ST Dirac delta function exp atf x t x s a Shift in s exp -at sin bit Ừ s a 2 bl2 exp at cos bit 5 a x a 2 bl2 tx f dx s ds d 0 _ A dz .vx .v - x 0 dr s2x s - sx 0 - 0 d x v X dx x x s - s ix 0 - s -2x 0 . . . -sx -2 0 - x -1 Convolution integral Xi ơ- x2 r - a da- Xi s x2 .t 17.4 Matrices and determinants 17.4.1 Linear simultaneous equations The set of equations fliHi a12x2 . . . alnx b 21 1 a22x2 . . . 2n n bl a iXi a 2x2 a ztx b may be written symbolically Ax b in which A is the matrix of the coefficients