Axial flow compressors are required to operate over a wide range of mass flow rate and rotational speeds at high efficiency in industrial gas turbines. However, the useful range of operation of the axial compressor is limited by the onset of two instabilities known as surge and rotating stall. To resolve these problems, variable stator blades or VGVs are considered by optimising the blade setti...

Active flow control methods are commonly used in expanding the operating range of compressors. Indeed, unsteady active main focus researchers due to their effectiveness. For constructing an system, reliable actuators significant. To compare with conventional such as synthetic jet and rotating valves, fluidic oscillators have structurally robust characteristics can generate self-excited self-sus...

screw compressors are used to produce the compressed air in the refineries. because of the frequent failures and high prices of these compressors, this research was done to determine the failure causes in one of these compressors. in this study and after about 603 working hours , female rotor compressor had been fractured. metallurgical and other experiments showed that the defect in cooling wa...

The increasing importance of Unicode for text files, for example with Java and in some modern operating systems, implies a possible doubling of data storage space and data transmission time, with a corresponding need for data compression. However it is not clear that data compressors designed for 8-bit byte data are well matched to 16-bit Unicode data. This paper investigates the compression of...

An experimental rig has been built to test a horizontal scroll compressor and a reciprocating compressor of similar size and capacity. The compressors were tested with refrigerant.R404A operating at varying evaporator and condenser temperatures. The paper provides much needed information regarding the efficiency of the compressors operating under the same conditions with the same system paramet...

Title of Dissertation: NOISY PRECURSORS FOR NONLINEAR SYSTEM INSTABILITY WITH APPLICATION TO AXIAL FLOW COMPRESSORS Taihyun Kim, Doctor of Philosophy, 1997 Dissertation directed by: Professor Eyad H. Abed Department of Electrical Engineering This dissertation addresses monitoring of nonlinear systems for detection and prediction of incipient instabilities. The analysis and design presented here...


 Recently,
 there
 has
 been
 a
 growing
 interest
 in
 queryable
 XML
 compressors,
 which
 can
 be
 used
 to
 query
 compressed
 data
 with
 minimal
 decompression,
 or
 even
without
 any
 decompression.
 At
 the
 same
 time,
 there
 are
 very
 few
 such
 projects,
 which
 have
 been
 made
 available
 for
 testing
 and
 comparisons.
In
this
paper,
we
report
our
current
work
on
two
novel
quer...

This paper proposes lossless image compressors that are simpler than existing ones and yet still work well. The compressors process images in raster-scan order, and to code a pixel first estimate that pixel’s value by using a linear function of already-coded pixels. Next the compressors estimate the uncertainty in the first estimate by using a nonlinear function of already-coded pixels. Finally...