Logic modules

Logic modules are used to monitor the counting rate of single detectors and the relative times at which radiation is detected. A fast signal derived from the detector itself, the preamplifier, or from a timing-filter amplifier is sent to a discriminator. 

The most advanced application of TFML technology has been reported by NEC for their SX-1 and SX-2 supercomputers that are currently in production (81). The logic module for the computer contains 36 ceramic chip... 

Patients exceeding the maximum opioid daily dose and those exhibiting intolerability and increased adverse events despite rotation are candidates for step-4 interventional therapy [9,10]. Techniques that may be offered include spinal and peripheral neural stimulation, which provides effective non-pharmaco-logical modulation of pain transmission. Intrathecal infusions of morphine or hydromorphone either alone... 

The main idea of the methodology is to use link modules to make connections between measurements, logic modules and equipment. The link modules are parameterised with links to the hardware that implement that link, as hardware failures may cause the received value of a variable to be interpreted differently. 

The modular composition of the model is illustrated in Fig. 1. The main components of the model are the logic modules (APU and VU), the various link modules, process module, and a failure module. The connections in Fig. 1 are either one-to-one or one-to-many, and should be read as creates an instance of . For example, the main module creates a single instance of the failure module. 

In order to simplify the model we did some light abstractions. As an example, the measurement devices have a failure mode freeze that can be modelled using a single variable that stores the device s output at the previous time step. We made an abstraction in which we use a random variable instead. Another abstraction was to replace unneeded logic modules with interface modules. An interface module contains no function blocks, and the outputs of the module are defined as free variables. Both of these abstractions are over-approximations that preserve the truth value of universal properties (e.g. safety properties). If the over-approximated model does not have a bad state, then a bad state cannot exist in the more concrete model either. 

The PRA model did not include any descriptions of time delays used in the I C systems, and thus no timers were added to the logic modules. However, in real I C systems timers are regularly used. Adding timers into the function block diagrams is straightforward but doing so may lead to a model that is computationally more challenging. 

SLAM partitions register-transfer netlists into bit-sliced stacks and glue-logic modules. It also selects a floorplan style that optimizes area utilization. SLAM consists of four parts (i) Partitioner, (ii) Stack placer and router, (iii) Glue-logic binder, and (iv) Floorplanner,... 

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