The 4.0 kbit/s speech codec described in this paper is based on a
Frequency Domain Interpolative (FDI) coding technique, which
belongs to the class of prototype waveform Interpolation (PWI)
coding techniques. The codec also has an integrated voice
activity detector (VAD) and a noise reduction capability. The
input signal is subjected to LPC analysis and the prediction
residual is separated into a slowly evolving waveform (SEW) and
a rapidly evolving waveform (REW) components. The SEW
magnitude component is quantized using a hierarchical
predictive vector quantization approach. The REW magnitude is
quantized using a gain and a sub-band based shape. SEW and
REW phases are derived at the decoder using a phase model,
based on a transmitted measure of voice periodicity. The spectral
(LSP) parameters are quantized using a combination of scalar
and vector quantizers. The 4.0 kbits/s coder has an algorithmic
delay of 60 ms and an estimated floating point complexity of
21.5 MIPS. The performance of this coder has been evaluated
using in-house MOS tests under various conditions such as
background noise. channel errors, self-tandem. and DTX mode
of operation, and has been shown to be statistically equivalent to
ITU-T (3.729 8 kbps codec across all conditions tested.
Communication between various devices makes it possible to pro-
vide unique and innovative services. Although this interdevice com-
munication is a very powerful mechanism, it is also a complex and
clumsy mechanism, leading to a lot of complexity in present day
systems. This not only makes networking difficult but also limits
its flexibility.
Regardless of the branch of science or engineering, theoreticians have always
been enamored with the notion of expressing their results in the form of
closed-form expressions. Quite often, the elegance of the closed-form solution
is overshadowed by the complexity of its form and the difficulty in evaluating
it numerically. In such instances, one becomes motivated to search instead for
a solution that is simple in form and simple to evaluate.
Regardless of the branch of science or engineering, theoreticians have always been
enamored with the notion of expressing their results in the form of closed-form
expressions. Quite often the elegance of the closed-form solution is overshadowed
by the complexity of its form and the difficulty in evaluating it numerically. In
such instances, one becomes motivated to search instead for a solution that is
simple in form and likewise simple to evaluate.
Complex networks are powerful allies of our quest to tackle complexity in all
of science. Many lines can be written about the benefits of using networks to
study complex systems. Nevertheless, if I had to name their single most appealing
property,Iwouldsaysimplicity.Onecanmaptheinteractingelementsofanysystem
to a set of nodes, and connect these nodes with a set of links according to their
interactions.
In order to improve the spectral efficiency in wireless communications, multiple
antennas are employed at both transmitter and receiver sides, where the resulting
system is referred to as the multiple-input multiple-output (MIMO) system. In
MIMO systems, it is usually requiredto detect signals jointly as multiple signals are
transmitted through multiple signal paths between the transmitter and the receiver.
This joint detection becomes the MIMO detection.
This book is a result of the recent rapid advances in two related technologies: com-
munications and computers. Over the past few decades, communication systems
have increased in complexity to the point where system design and performance
analysis can no longer be conducted without a significant level of computer sup-
port. Many of the communication systems of fifty years ago were either power or
noise limited. A significant degrading effect in many of these systems was thermal
noise, which was modeled using the additive Gaussian noise channel.
The planarization technology of Chemical-Mechanical-Polishing (CMP), used for the manufacturing of multi-
level metal interconnects for high-density Integrated Circuits (IC), is also readily adaptable as an enabling technology
in MicroElectroMechanical Systems (MEMS) fabrication, particularly polysilicon surface micromachining. CMP not
only eases the design and manufacturability of MEMS devices by eliminating several photolithographic and film
issues generated by severe topography, but also enables far greater flexibility with process complexity and associated
designs. T
In this book for the optimisation of assembly conveyor lines we are dealing with series part production
featured by a medium complexity degree and a medium number of individual components and assembly
technique alternatives. Modern production techniques for medium to large series products or mass
production usually involve assembly conveyor lines. They still use hand labour more or less automated.
The aim is to have monotonous and similar in type operations or such causing fatigue, stress and
production traumas, gradually replaced by automated assembly cycles, means and techniques. This
usually widely involves industrial robots and handlers. Higher productivity, lower cost and higher quality
of assembled products are usually required.
