ADCs

The approach behind the development of ADCs as oncology therapeutics is to combine the selectivity of an antibody toward tumor antigens with the potency of a cytotoxic agent in an effort to increase target specificity and reduce systemic 

---

The evaluation of the deconvolution results show that time resolution is better or equal to 1 with the chosen processing time unit of 0.08 microseconds (respectively a rate of 12.5 MHz). First signals processed conservatively have been acquired with a samplerate of 12.5 MHz. A Fourier analysis shows that the signals spectras do not have energy above 2.0 MHz. This means that a sampling rate of 4.0 MHz would have done the job as well. Due to the time base of the ADC an experimental check with a sample rate of 5.25 MHz has been carried out successfully. 

The sample frequency of the ADC (analogue to digital converter) should be 8 times higher than the test frequency (centre frequency of the spectrum). In dependence of the application, different ADC- boards are used. A standard board (20520) provides 8 bit resolution and up to 100 Msamples/s in single shot mode. For manual tests, up to 400 Msamples/s can be reached in the repetition mode. For scanning systems with high frequencies boards up to 400 Msamples/s (single shot) are available. 

In order to test a wide range of materials a series of ultrasonic pulser/receiver boards has been developed. In combination with an ADC-board (analogue-to-digital converter) a PC can be converted to a high performance ultrasonic system not only for manual testing but also for automatic testing and imaging systems. 

The ADC boards used for the PC systems provide a resolution of 8 bit with single-shot sampling of up to 400 Msamples/s. 

An alternative to the TAC and PHA/ADC is the time-to-digital eonverter (TDC), a unit that eombines the fiinetions of the TAC and PHA/ADC. There are start and stop inputs and an output that provides a binary number direetly proportional to the time diflferenee between the stop and start signals. The TAC ean be direetly eonneeted to a MCA or PC with the appropriate digital interfaee. 

A computer-controlled bandpass filter system controls the size of the acquired spectral window. Typically, this is set to about 120% of the desired sweep width. Only frequencies within these limits are allowed to reach the ADC. Those frequencies outside the limits would only contribute to the noise in the final spectmm. The need for this system is dictated by the nonselective nature of the excitation rf pulse. 

Fig. 13. Bubble column flow characteristics (a) data processing system for split-film probe used to determine flow characteristics, where ADC = automated data center (b) schematic representation of primary flow patterns.

For the amplifier pulse to be recognized in the ADC, it must exceed the lower level set by a discriminator, which is used to prevent noise pulses from jamming the converter. Once the pulse is accepted it is used to charge a capacitor that is discharged through a constant current source attached to an address clock typically... 

K.Pawlik, J. Pospiech and K. Liicke, "The ODF approximation from pole figures with the aid of the ADC method" Textures and Microstructures 14-18, 66,1991,... 

Adapted from I ADC Drilling Manual, 10th edition, 1982 Courtesy lADC. 

The above data are obtained from the I ADC Drilling Manual, Section B, p. 1, revised January 1975. 

In 1987, I ADC developed a revised standard nomenclature for roller bits which includes a classification chart and a four-character bit code. All manufacturers must classify their bits in a prescribed manner on the lADC classification chart. The classification includes four categories series, types, feature, and additional features. Figure 4-136 shows an lADC classification chart. A letter used in the fourth position of the four-character lADC code indicates additional design features specified in Table 4-91. 

Figure 4-165. I ADC bit dull grading codes—bold characters for fixed-cutter bits [55]. (Courtesy SPE.)...

---