An optimum algorithm to find interaction positions of a γ-ray in a Ge-detector is being investigated by analyzing pulse shapes of the Ge-detector VEGA [1, 2]. The VEGA detector consists of four Ge crystals forming like a four leaf clover. Each crystal has four electric segmentations in radial quarters. A collection time of electron and hole (eh) depends on their drift length, therefore the slop...

Introduction: Most common glioma tumors are tumors of the central nervous system (CNS) which are the cause of about 40 to 50 percent of brain tumors. This type of cancer includes 2 to 3 percent of cancers in the world. Conventional MRI is powerless in the detection and differentiation of benign and malignant tumors. In this case, diffusion weighted imaging (DWI) can create cont...

A 1.2 V 7-bit 1 GS/s CMOS flash ADC with an interpolation factor of 4 is implemented by using a 0.13 μm CMOS process. A digital calibration of DC reference voltage is proposed for the 1 preamp array to compensate for the input offset voltage of differrential amplifiers without disturbing the high-speed signal path. A 3-stage cascaded voting process is used in the digital encoder block to elimin...

An 8-b 650-MHz folding analog-to-digital converter (ADC) with analog error correction in the comparators is presented. With an input frequency of 150 MHz, 7.8 effective bits are obtained. The ADC is implemented in a 1-pm 13-GHz triple-level interconnect bipolar process, requiring 850 mW from a single -4.5-V supply. The die size is 4.2 mm’.

In energy constrained signal processing and communication systems, a focus on the analog or digital circuits in isolation cannot achieve the minimum power consumption. Furthermore, in advanced technologies with significant variation, yield is traditionally achieved only through conservative design and a sacrifice of energy efficiency. In this thesis, these limitations are addressed with both a ...

Ultra wideband radio (UWB) is a new high-speed wireless technology that uses subnanosecond pulses to transmit information. Implementing an all-digital UWB receiver has numerous benefits ranging from low cost and ease of design to flexibility. Digitizing an RF signal near the antenna, however, introduces its own set of challenges and has traditionally been considered infeasible. A high-speed, hi...

background and purpose : there has been no report in which preoperative evaluation of adc for prediction of post therapeutic outcome was presented. the aim of our study was to retrospectively evaluation the use of the apparent diffusion coefficient (adc) for the prediction of malignancy and the outcome of malignant astrocytic tumors. methods: we reviewed mri of 26 male and 14 female patients wi...