Internal carotid-posterior communicating artery (IC-PC) aneurysms account for more than 20% of all intracranial aneurysms. As a result of the increase in coiling, there has also been an increase in recurrent IC-PC aneurysms after coiling. We present our experience of 10 recurrent IC-PC aneurysms after coiling that were retreated using surgical or endovascular techniques in order to discuss the ...

Orthogonal Frequency Division Multiplexing (OFDM) is one of the modulation techniques used in digital video broadcasting systems. A significant disadvantage of OFDM is that it has a high peak-to-average power ratio (PAPR). This means that the output amplifiers of digital television transmitters must be designed to handle signals that are far in excess of the mean levels. These amplifiers are ex...

In this paper, we propose a low-complexity peak-to-average power ratio (PAPR) reduction scheme that combines both multi-band (MB)-Hadamard precoding and clipping for the optical orthogonal frequency division multiplexing (OFDM) systems. Approximations of PAPR distribution for baseband OFDM signals are analyzed and the effective signal-to-noise ratio (SNR) of the whole transmission link consider...

Recent developments in cerebral angiography equipment and workstations have made it possible to produce clear angiograms useful images for neurosurgery. At our institution, we routinely perform aneurysm clipping after presurgical simulation using imaging data obtained three-dimensional angiography. This report describes the clinical significance of clipping.

A modified Orthogonal Frequency Division Multiplexing (OFDM) system for robust progressive image transmission is proposed in this paper. A joint source-channel coder (JSCC) is employed in the modified OFDM system. The set partitioning hierarchical trees (SPIHT) used as source coder, and The Low-Density Parity-Check (LDPC) used as a channel coder. The SPIHT coder is modified to generate four dif...

High peak-to-average power ratio of the transmit signal is a major drawback of multi-carrier transmission such as Orthogonal Frequency Division Multiplexing, which causes power inadequacy in Radio Frequency section of the transmitter. This paper describe some of the important PAPR reduction techniques for multi-carrier transmission including amplitude clipping and filtering, partial transmit se...

Multiple-Input Multiple-Output (MIMO) technique combined with Orthogonal Frequency Division Multiplexing (OFDM) is the proficient air interface for upcoming generations of high data rate and high-speed wireless communication. Nonetheless, such a system suffers from drawback peak-to-average power ratio (PAPR) when symbol phases in OFDM subcarriers line up fashion that constructive formation larg...

Measurement of the spatial frequency response (SFR) of digital still cameras by slanted-edge analysis has been established for several years. The method, described in standard ISO 12233, has also been applied to other image acquisition subsystems such as document and print scanners. With the frequent application of the method and use of supporting software, questions often arise about the form ...