Self-Portrait in a Flat Cap

Rembrandt van Rijn; 2 ft. 3 23/32 in.x 1 ft. 11 5/32 in.; oil on oak

Self-Portrait

Rembrandt van Rijn; 2 ft. 7 39/64 in.x 2 ft. 2 1/2 in.; oil on canvas

Self-Portrait

Francisco Goya; 6 1/32 in.x 3 37/64 in.; brush and gray wash on laid paper

Self Portrait

Karel Dujardin; 11 7/32 in.x 8 21/32 in.; oil on copper

Self-Portrait

Joshua Reynolds; 2 ft. 2 in.x 1 ft. 6 47/64 in.; oil on canvas

Self-Portrait (after Reynolds)

Henry Bone; 10 1/8 in.x 7 23/32 in.; enamel on coper

Self-Portrait

Simon Bening; 3 11/32 in.x 2 1/4 in.; tempera and gold leaf on parchment

Self-Portrait

Anthony van Dyck; 3 ft. 11 1/8 in.x 2 ft. 10 39/64 in.; oil on canvas

Self portrait of Rembrandt leaning on a Stone Sill, 1st state

Rembrandt van Rijn; 8 5/32 in.x 6 29/64 in.; etching on paper

Self-portrait of Rembrandt leaning on a Stone Sill, 2nd state

Rembrandt van Rijn; 8 5/64 in.x 6 29/64 in.; etching on paper

Self-Portrait

Tsuguji Fujita; 1 ft. 3 35/64 in. x 10 15/64 in.; woodcut

The Garden of Earthly Delights Triptych, interior, center panel, lower right: dancers under an owl; self-portrait in lower right corner

Hieronymus Bosch; grisaille, oil on wood

AC self-bearing motors with a bridge configured winding

Magnetic levitation bearings eliminate friction, wear and the need for lubrication and so have high speed capability and potential for vibration control. One noteworthy development in the realm of magnetic levitation is the self-bearing or bearingless motor - an electromagnetic machine that supports its own rotor by way of magnetic forces generated by windings on its stator. Accordingly, various winding schemes have been proposed to accomplish the task of force production. This thesis proposes a novel concept of winding based on a bridge connection for polyphase self-bearing rotating electrical machines with the following advantages: • the connection uses a single set of windings and thus power loss is relatively low when compared with self-bearing motors with conventional dual set of windings. • the motor and levitation controls are segregated such that only one motor inverter is required for the normal torque production and levitation forces are produced by using auxiliary power supplies of relatively low current and voltage rating. The usual way of controlling the motor is retained. • there are many variant winding schemes to meet special needs. • independent power supplies for levitation control offer redundancy for fault tolerance. This thesis dwells specifically on the conceptual design and implementation of the proposed single set of windings scheme. The new connection has been verified to exhibit characteristics of a self-bearing motor via coupled-field finite element analysis: results are crosschecked analytically. Power loss and other aspects such as cost, design implementation are compared to support the newly proposed connection as a potential alternative to present designs.

CADS*: Computer-Aided Development of self-* systems

We present the prototype tool CADS* for the computer-aided development of an important class of self-* systems, namely systems whose components can be modelled as Markov chains. Given a Markov chain representation of the IT components to be included into a self-* system, CADS* automates or aids (a) the development of the artifacts necessary to build the self-* system; and (b) their integration into a fully-operational self-* solution. This is achieved through a combination of formal software development techniques including model transformation, model-driven code generation and dynamic software reconfiguration.

Peak -to -average power ratio reduced parallel interference cancellation Multicarrier-Code Division Multiple Access system with anti -interference property

Orthogonal Frequency-Division Multiplexing (OFDM) has been proved to be a promising technology that enables the transmission of higher data rate. Multicarrier Code-Division Multiple Access (MC-CDMA) is a transmission technique which combines the advantages of both OFDM and Code-Division Multiplexing Access (CDMA), so as to allow high transmission rates over severe time-dispersive multi-path channels without the need of a complex receiver implementation. Also MC-CDMA exploits frequency diversity via the different subcarriers, and therefore allows the high code rates systems to achieve good Bit Error Rate (BER) performances. Furthermore, the spreading in the frequency domain makes the time synchronization requirement much lower than traditional direct sequence CDMA schemes. There are still some problems when we use MC-CDMA. One is the high Peak-to-Average Power Ratio (PAPR) of the transmit signal. High PAPR leads to nonlinear distortion of the amplifier and results in inter-carrier self-interference plus out-of-band radiation. On the other hand, suppressing the Multiple Access Interference (MAI) is another crucial problem in the MC-CDMA system. Imperfect cross-correlation characteristics of the spreading codes and the multipath fading destroy the orthogonality among the users, and then cause MAI, which produces serious BER degradation in the system. Moreover, in uplink system the received signals at a base station are always asynchronous. This also destroys the orthogonality among the users, and hence, generates MAI which degrades the system performance. Besides those two problems, the interference should always be considered seriously for any communication system. In this dissertation, we design a novel MC-CDMA system, which has low PAPR and mitigated MAI. The new Semi-blind channel estimation and multi-user data detection based on Parallel Interference Cancellation (PIC) have been applied in the system. The Low Density Parity Codes (LDPC) has also been introduced into the system to improve the performance. Different interference models are analyzed in multi-carrier communication systems and then the effective interference suppression for MC-CDMA systems is employed in this dissertation. The experimental results indicate that our system not only significantly reduces the PAPR and MAI but also effectively suppresses the outside interference with low complexity. Finally, we present a practical cognitive application of the proposed system over the software defined radio platform.