Simple adaptive control implementation

The control network adapts to the changing execution delays of the operations. It has several advantages that include modularity, distribution of control, uniform handling of both fixed and data-dependent delay operations, and support for multiple concurrent execution flows. We describe now a simple adaptive control implementation that satisfies these requirements. Although it may not be precise in terms of control delay, we use this simple model to justify a more elaborate control scheme that is presented in the next section which satisfies the preciseness requirement 

Let pred vi) and succ(v,-) denote the set of predecessors and successors of a vertex v,- in the sequencing graph G, respectively. We define the handshaking signals for a control element CEi below  

Note that completci is generated by the data-path. 

Note that upon completion, a vertex remains in the ready state if donee is also asserted. This corresponds to the case when the completion of this vertex results in the completion of the entire sequencing graph. 

Loop Control Element Loop Interface Control M 

---

A variety of rules have been developed to control the movement and adaptation of the simplex, of which the most famous set is due to Nelder and Mead (Olsson and Nelson, 1975). The Nelder-Mead simplex procedure has been successfully used for a wide range of optimization problems and, due to its simple implementation, is amongst the most widely used of all optimization techniques. Importantly for the current application, simplex optimization is a black-box technique since it uses only the comparative values of the function at the vertices of the simplex to advance the position of the simplex, and it therefore requires no knowledge of the underlying mathematical function. It is also well suited to the optimization of expensive functions since as few as one new measurement is needed to advance the simplex one step. In its usual form, simplex optimization is suitable only for unconstrained optimization, but effective constrained versions have also been developed (Parsons et al., 2007 ... 

Finally, the application of optimal control theory to DNP studies needs to be discussed. Optimal control theory is a means to systematically design and optimize pulse sequences to maximize the efficiency of transfer between spin states. While this method was initially introduced to benefit high-resolution NMR studies, it has recently been adapted to improve the electron-nuclear polarization transfer in DNP applications by considering simple two- or three-spin systems. " While no experimental implementation of DNP pulse sequences designed by optimal control methods has been reported, these methods have the great potential to enhance DNP performance at X-band, due to the powerful pulsed ESR hardware that is commercially available at these frequencies. 

The major emphasis will be on the minimum variance stochastic control schemes of Box and Jenkins ( b) and Astrom (l ), and on modifications of them. These schemes have seen successful application in the polymer industry, and they are intuitively appealing and yet simple enough to be implemented by the plant operators using either a programmable hand calculator or control charts and tables. More powerful adaptive versions can be implemented if a small online mini-computer is available. 

Automatic systems based on FIA were also implemented for wine analysis. In a comprehensive review, Ferreira and coworkers [97] remarked that some systems had limitations as many of them were only tested with a particular wine type or demanded a previous treatment of the sample before injection. The lack of robustness of some manifold components (tubing of peristaltic pumps, some types of injection devices) was also thought to prevent the extensive use of FIA in industrial laboratories [98]. SIA has been proposed as a mechanically simple alternative to FIA [99]. As previously stated, SIA is based on the sequential aspiration of well-defined sample and reagent zones into a holding coil by means of a multiposition valve. The flow is then reversed and the stacked zones are mixed and propelled to the detector, where the reaction product is monitored. As already described for other beverage matrices (water, juices), the SIA of wine has been developed in recent years for the determination of more than 20 species and several aspects of these systems were reviewed by Segundo et al. [100] in a recent paper. The authors focused on the implementation of in-line treatment and the adaptation of system operation through software control to enable determination in different kind of wines. 

Perhaps the most important reason leading to the industrial implementation of metallocene catalysts, in addition to their high activity and excellent microstructural control, is that they can be easily adapted to industrial olefin polymerization processes. The transition from Ziegler-Natta or Phillips catalysts to metaUocenes is sometimes called drop-in technology exactly to indicate that the new catalysts can simply be dropped in the existing reactor. Of course, reality is often not as simple as catchy terms may indicate, but the fact remains that metallocenes can be introduced into existing industrial processes without a prohibitively large number of adjustments. 

A key component developed as part of the VSTL is irrrproved vehicle self-awareness. A number of automated safety arrd health-based behaviors have been implemented to support simple, reliable, safe access to flight testing. Several command and control applications provide an irrterface between the operator and the vehicles. The level of interaction includes remotely piloted, low-level task control and high-level mission management. The mission management apphcation was used to explore opportunities associated with health-based adaptations and obtain some initial information. 

---