Dear Vafa,
Thanks all for the answers. As suggested by Akira and Herbert, I edited eps image.The result with xelatex is ok but the result with latex+dvips+ps2pdf is not ok (it is out of the \fbox). I have attached the generated pdf file. It seems a bit odd; they behave differently.
Strange. I attach test.tex, w.eps and test.pdf. Here test.pdf is created by latex test dvips -Ppdf test ps2pdf test.ps test.pdf Thanks, Akira
test.tex
Description: Binary data
w.eps
Description: PostScript document
test.pdf
Description: Adobe PDF document
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