AST node

However complex an algorithm may be, it ultimately has to be executed by a collection of primitive hardware units, which HlFl considers to be finite state machines. We model a finite state machine hy an AST node. This architectural model was inspired by the concept of applicative state transitions (ASTs) as published by Backus [2], and, in acknowledgement of that fact, we have named our node accordingly. 

The capabilities of a primitive hardware unit are specified by a number of behavior descriptions corresponding to each of its states. The behavior can change from state to state (e.g., an ALU may in one state execute a logic function and in another an arithmetic operation). Therefore, we say that an AST node has a temporal behavior. 

The second type of node in HiFl expresses parallelism and is called a structure node. It is a network of nodes, of either type, in which ports of nodes are connected by edges. The nodes in such a network are concurrent processes that are only aware of their local state and communicate asynchronously with each other by edges. The communication between the AST nodes of such a network is according the model of communicating sequential processes (CSP) [15]. In the context of CSP, communication is seen as a shared event between two subprocesses. This means that the production of data in one AST process is synchronized with the consumption of data in another AST. 

In case of a systolic array, the schedule vector A specifies that the AST node at index point 7 is to be executed at time step A 7. The vector A also specifies that the data which are transmitted over an edge defined by a dependence vector di is delayed A di time steps, so that the data will arrive in time at the node of the DG by which they are to be processed. In case of a wavefront processor array, the schedule vector A only specifies the ordering of the computations and the data storage capacity of the edges. Furthermore, the node at index point 7 will be mapped onto the processor at index point P j during the array synthesis step. Note that the S-T transformation only defines the S-T allocation... 

Figure 11 Compound node of the regularized Floyd-Steinberg DG implemented as a structure node. The triangular nodes denote input (i jrxx) or output (o xx) selectors. The circular node is the original AST node. The bars denote source and sink nodes.

In the above code, node gets replaced with a reference that will point to a AST node at runtime. 

ASCENDING NODE Ast. Tlie north NODE of astrology has f row ancient times beer, signified by the sigil but the following form is copied... 

DESCENDING NODE Ast. The following sigil is copied from the Greek text given by OMONT 1804 It is said to be the k tJbabazon or... 

NODE Ast. The term node is most frequently used without further designation for the Moon s Node, which is dealt with in the present context under CAPUT and CAUDA. However/ in certain modern schools of astrology, e ecially in those concerned with heliocentric charts, the particular node of a planet is indicated by enclosing the traditional planetary sigil in the basic form for the caput or cauda, thus t/ h which is the node of Jupiter, taken from SUCHER 1970. 

Figure 30 (Middle) Single-metal-ion-based MBBs (tri-connected nodes and linear spacers) facilitate the assembly of a MOC, which is utilized as 8-connected SBB to generate ZMOFs. Zeolitic nets with AST (top left) and LTA (top right) are constructed based on relations with regular (8-connected)-based nets (bottom). The flu net (bottom left) corresponds to ast-ZMOF (middle left) and the reo net (bottom right) to Ita-ZMOF (middle right) when the 8-connected nodes are augmented, or replaced by metal-organic cubes (i.e., D4Rs).

The effects of changing the proton content of solutions bathing excitable membranes has been the subject of many reports in the j)ast. (1-7). Two main effects were commonly observed although they differed quantitatively upon changing the nerve preparation a) a shift on the voltage axis of the parameters characterizing nerve excitability (similar to the action of divalent ions (8)), b) a variation of the steady-state maximum conductance of the open channels selective for sodium and potassium ions. A third type of effects concerns phenomena such as the voltage-dependent block of Na" "-channels observed by Woodhull (9) in the node of Ranvier. 

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