With the development of ball grid array (BGA), the strength of BGA becomes important. High speed single solder ball test is one effective method to test BGA strength. This design provides one machine to test single sold ball strength at high speed. The advantage of this design is multi-solder balls .....
[更多]
This improved material relates to novel planar materials having band gap properties, and in particular to such materials formed with fractal patterns. Band gap materials are ideal for shielding electromagnetic (EM) radiation as they have a gap in the transmission band thus blocking transmission of E.....
[更多]
JPEG2000, a newly developed international standard for still image compression. It can provide superior objective and subjective image quality and can reduce file size by 40% compared with JPEG while retaining the same visual quality.Rate control or rate allocation is of great necessity to control t.....
[更多]
In heavy metal producing industries such as electroplating, metal-finishing, steels, chemical manufacturing, leather tanning, the handling of effluent has always been the main concern. Improper treatment to the wastewater before it is drained out into rivers or oceans will cause a great pollution an.....
[更多]
It is very difficult to shield low frequency sound waves. This is mainly because in order to cause wave scattering or reflection, the usual wisdom is that the size of the scatterers must be on the order of the wavelength. Since low frequency sound has long wavelength, it follows that the shielding m.....
[更多]
| |< <- | [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] | -> >| |
