Functional hierarchy

G. M. Berntson, Topological scaling and plant root system architecture developmental and functional hierarchies, New Pliytol. I35 62 (1997). 

Thus, autocatalysis occurs in biology across various levels of structural and functional hierarchies, from a complete plant (or fungus, animal) over single cells down to such molecules which take part in metabolism and get doubled in cell budding and reproduction also. Both the... 

Bachiller, D., Macias, A., Duboule, D., Morata, G. 1994. Conservation of a functional hierarchy between mammalian and insect Hox/HOM genes. EMBO J. 13, 1930-1941. 

Recently, the author advocated the application of the systems approach in the analysis and synthesis of a biotechnological process ( 1). The hierarchy of a biological system involves structural, functional, descriptive, control and dynamic organization. Structural and functional hierarchies of a biotechnological process are depicted in Tables I and II. In Table II a compartmental level is omitted. This is possible as long as the translocation of substances between organelles and cytoplasm is not important. The scheme of functions should be understood in both directions,... 

Table I Structural and Functional Hierarchies of a Biotechnological Process...

The description hierarchy acquires different ways physical processes in mass and energy balances information processing and control optimization of the system at the reactor level or as a whole (41). The most elaborate concept of descriptive hierarchy, including a set of programs, was published and routinely used by Klir (42). As descriptive hierarchy usually follows structural and functional hierarchy, it is thus assured that the modelled object possesses enough structural and functional features, otherwise the reactor control by means of such models would not satisfactorily respond to changing conditions. 

An internal computer functional hierarchy exists for processing information input emd generating appropriate output. Essential functions of this hierarchy are represented by the modules of modeling, simulation control, and rendering. Built onto appropriate ha ware structures, this functionality is realized by software technology. 

We need to choose which variables and family of functions to utilize, and we make those choices correctly if we think that the variables and function hierarchy selected somehow map onto the basic physical reality at hand (Norton 2003 656). 

A primary task in high-level architecture synthesis is the extraction of the data flow from a given algorithm description. The term data flow is defined here as the combination of operations and dependencies between them that define the algorithm. In contrast, control flow is then defined as a (partial) ordering of computations meeting the restrictions of their dependencies. The control flow is usually specified by introducing loops and function hierarchy. 

Some short as well as discontinuous fibers can be grown from the vapor phase, some formed from the liquid phase, either a viscous melt or a viscous solution, and others yet are derived from a solid precursor or green fiber. The present book subordinates the discussion of individual or groups of fibers to the functional hierarchy of these process concepts. 

Functional Hierarchy versus bureaucracy. A functional hierarchy is not the hierarchy that exists as a barrier in health care today, such as the hierarchy of power differentials between physicans and nurses, physicians and patients. Rather, a functional hierarchy is a system of formal rules, structures, procedures, training, and decision making in the service of organizational mission and values. In a safety culture, there is a clear chain of command so that jteople at the sharp end know where to go for help, but hierarchies are flexible and can be modified when organizational conditions so warrant. Senior managers see the big picture and therefore do not micromanage instead, they attend to patterns and systems. De-... 

A structure of functional hierarchy, not bureaucracy, fiar day-to-day operations makes everyone accountable for safety. It ensures training, procedures, and pattern detection. 

Fig. 2.12 Basic concept of functional hierarchy of hierarchical hologram. In principle, no interference occurs between the two layers, the far-mode and the near-mode...

The simplest type of memory function approximation is to truncate the memory function hierarchy by assuming that the nth order memory function decays exponentially. This leads to a truncated continued fraction for the Fourier transform of Cj (t) with only one free parameter. Although the itinerant oscillator model in two dimensions is identical to a three term truncated continued fraction/ in three dimensions there is no such simple relationship this must be considered as an approximation with no prediction about C j j(t). 

The parts in the component library are abstracted and organized into a functional hierarchy. The leaf parts are termed physical parts, while all other parts are termed abstract parts. SFF is performed along this hierarchy. After SIT selects a part in the hierarchy, SFS is performed by selecting a template from a library. A template is essentially a fragment of a schematic drawing that indicates the appropriate connections for the part. 

For each design situation, there must be exactly one suitable template. If there is a case where more than one template is satisfactory, more information must be added to the design situation to disambiguate them. Alternatively, both templates can be abstracted to separate nodes in the functional hierarchy, and SFF can be used to select one of them. Thus, SFS consists of matching the design situation with the set of templates available. 

The actual functional hierarchy has a large number of nodes at present it contains over 7(X). Nodes represent parts as complex as microiM-ocessors, or as simple as resistors. 

The functional hierarchy is really a directed, acyclic graph, not a simple tree. This is because parts may implement multiple functions, and have multiple function units. Thus, there are nodes with in-degree greater than one, and the links do not have to observe strict hierarchy (i.e. a part may be linked to parts at various abstraction levels). For example, in Figure 5, a section of an actual functional hierarchy is shown. Notice that the part 6846 is linked to a read-only memory (G.ROM-0), a timer (68XX TIMER 0), and a parallel device(68XXJ>IO.O). 

There are several distinct functional hierarchies in Ml to such things as clock generators, crystals, and resistors. 

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