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A new kind of analog integrator has been developed for a magnetic diagnostic system on the Experimental Advanced Superconducting Tokamak. Although the previous analog integrators are single-ended input, which has low common-mode rejection ratio (CMRR), a different kind of integrator, a difference integrator is introduced which has the same structure as a standard difference amplifier. The linear drift compensation method is used for determining the effective drift slope; then, the plasma control system uses the drift slope to rectify the integration signal in real time. To improve the maintainability and testability of the integrator system, a new integrator controller has been developed. The new controller uses an advanced reduced instruction set computing machine microcontroller and the lightweight IP protocol stack to realize the network control. The tests show that the upgraded integrator works well, its CMRR is high up to 125 dB when the common voltage is 1.5 V, and the processed integration drift is about 10 mV in 1000 s of integration when the time constant is 20 ms. The performance is much better than the previous integrator.

For the purpose of keeping a plasma in steady state and avoiding instabilities, the experimental advanced superconducting tokamak (EAST) plasma control system (PCS) needs more diagnostic data produced by the EAST distributed subsystems to perform its complex control algorithms. To solve the transmission problem of all these data, a real-time communication system based on the messaging, real time, and grid real time operating system and reflective memory (RFM) network is designed. It is expected to enable the data acquisition (DAQ) systems of various EAST subsystems to be able to transfer the diagnostic data to the PCS in real time through the RFM network as the data are acquired. Then, the PCS can use these available data to carry out the necessary calculations according to the control algorithms and send the commands to the subsystems in every control cycle. To reach this goal, a small real-time communication system, adapted from the prototype of the EAST vacuum DAQ system (sampling rate of 10 KHz), was built for a performance test. In this test, the vacuum DAQ system transferred the acquired data to the PCS within the control cycle of $100~\mu \text{s}$ , which tentatively meets the abovementioned requirements. The test was performed for 1000 s to get a stable and reliable result, which is described in detail in this paper as well as plans for future work.

A thin Zn filter (/spl sim/300 /spl mu/m) and relatively low X-ray tube voltage (/spl sim/45 kV) is recommended for X-ray inspection of surface-mounted device solder joints on printed wiring boards (PWBs). An optimal filter minimizes the Si dose that could result in cumulative damage to sensitive integrated circuit (IC) nodes, yet provides good contrast for metals such as Cu traces on PWBs and device solder balls. While we expect orders of magnitude Si dose reductions when effective filters are inserted, a properly chosen filter should not attenuate the portion of the white X-ray spectrum required to image Cu, Sn, and Pb (solder balls). Some X-ray inspection suppliers can achieve a Si dose of as little as 0.060 rads, while other X-ray inspection suppliers, not yet optimized for minimum dose, may use as much as four orders of magnitude more dose. We used thermo luminescent detectors (TLDs) to measure the X-ray dose that IC product shipments would encounter during a shipping process, for example, as personal baggage or cargo, as /spl les/0.050 rads.