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Description
Oscillations in Nonlinear SystemsBy focusing on ordinary differential equations that contain a small parameter, this concise graduate level introduction to the theory of nonlinear oscillations provides a unified approach to obtaining periodic solutions to nonautonomous and autonomous differential equations. It also indicates key relationships with other related procedures and probes the consequences of the methods of averaging and integral manifolds. Part I of the text features
By focusing on ordinary differential equations that contain a small parameter, this concise graduate-level introduction to the theory of nonlinear oscillations provides a unified approach to obtaining periodic solutions to nonautonomous and autonomous differential equations. It also indicates key relationships with other related procedures and probes the consequences of the methods of averaging and integral manifolds.Part I of the text features introductory material, including discussions of matrices, linear systems of differential equations, and stability of solutions of nonlinear systems. Part II offers extensive treatment of periodic solutions, including the general theory for periodic solutions based on the work of Cesari-Halel-Gambill, with specific examples and applications of the theory. Part III covers various aspects of almost periodic solutions, including methods of averaging and the existence of integral manifolds. An indispensable resource for engineers and mathematicians with knowledge of elementary differential equations and matrices, this text is illuminated by numerous clear examples.
Binding Type: Paperback
Publisher: Dover Publications
Published: 05/20/2015
ISBN: 9780486673622
Pages: 192
Weight: 0.47lbs
Size: 8.42h x 5.37w x 0.40d
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Product Reviews
★★★★★ 4
Best pillow I’ve ever tried—hands down!
Size: Queen, Number of Items: 2
I’ve gone through a bunch of pillows over the years, but this BETU Cooling Pillow is by far the best one I’ve ever used. I sleep in literally every position—on my back, stomach, and sides—and this pillow works perfectly no matter how I’m laying.
It really does have a cooling effect, which I love as a hot sleeper. Just make sure your room is cool too, and it makes a big difference. It came vacuum-packed, but it fully expanded within just a few hours. I was able to sleep on it the same day it arrived, and it was super comfy right from the start.
I also washed and dried the pillowcase before using it, and it came out looking and feeling great—no shrinking or damage at all. Honestly, I look forward to going to bed every night now just because of this pillow. It’s supportive, comfortable, and totally worth it!
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Reviewed in the United States on February 21, 2026
★★★★★ 5
Excellent pillows!
Size: Queen, Number of Items: 2
This pack came with 2 pillows, one firm and one that was flatter and squishy. I absolutely love the flatter one! Most comfortable pillow I've ever used! The firm one was a bit too much for me, but my husband loves it.
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Reviewed in the United States on March 28, 2026
★★★★★ 3
It’s alright.
Size: Queen, Number of Items: 2
Not bad pillows. They are comfortable but mine came with an odd odor, kind of mildewy smell to it. Had to spray it down to tolerate sleeping on it.
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Reviewed in the United States on May 5, 2026
★★★★★ 5
Nice pillows
Size: Queen, Number of Items: 2
Have had these a few months and so far really like them!
They don’t really feel very cooling, but I also run VERY HOT so it could just be me. The foam holds up well and hasn’t flattened like others I’ve tried.
They come very compacted- I was shocked how much they expanded!
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Reviewed in the United States on March 22, 2026
★★★★★ 5
Mr.b
Size: Standard, Number of Items: 2
The pillows are cool and comfortable
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Reviewed in the United States on May 27, 2026