Abstract: A process controller implements an overall, user-developed control strategy in a process control network that includes distributed controller and field devices, such as Fieldbus and non-Fieldbus devices. A user defines the control strategy by building a plurality of function blocks and control modules and downloading or installing user-specified portions of the control strategy into the Fieldbus devices and the non-Fieldbus devices. Thereafter, the Fieldbus devices automatically perform the downloaded portions of the overall strategy independently of other portions of the control strategy. For example in a process control system that includes distributed field devices, controllers and workstations, portions of the control strategy downloaded or installed into the field devices operate independently of and in parallel with the control operations of the controllers and the workstations, while other control operations manage the Fieldbus devices and implement other portions of the control strategy.

Abstract: A method and apparatus for depositing a film by chemical vapor deposition comprises a showerhead for dispersing reactant gases into the processing space wherein the showerhead has a first space therein operable for receiving and dispersing the first reacting gas, and has a second space therein, generally isolated from the first space, and operable for receiving and dispersing the second reactant gas separate from the first gas dispersion for maintaining segregation of reactant gases and generally preventing premature mixture of the gases prior to their introduction into the processing space to prevent premature deposition in the system.

Abstract: A process controller implements smart field device standards and other bus-based architecture standards so that communications and control among devices are performed so that the standard control operations are transparent to a user. The process controller allows attachment to a theoretically and substantially unlimited number and type of field devices including smart devices and conventional non-smart devices. Control and communication operations of the various numbers and types of devices are performed simultaneously and in parallel.

Abstract: A process controller implements an overall, user-developed control strategy in a process control network that includes distributed controller and field devices, such as Fieldbus and non-Fieldbus devices. A user defines the control strategy by building a plurality of function blocks and control modules and downloading or installing user-specified portions of the control strategy into the Fieldbus devices and the non-Fieldbus devices. Thereafter, the Fieldbus devices automatically perform the downloaded portions of the overall strategy independently of other portions of the control strategy. For example in a process control system that includes distributed field devices, controllers and workstations, portions of the control strategy downloaded or installed into the field devices operate independently of and in parallel with the control operations of the controllers and the workstations, while other control operations manage the Fieldbus devices and implement other portions of the control strategy.

Abstract: A process controller implements an overall, user-developed control strategy in a process control network that includes distributed controller and field devices. A user defines a module control strategy by specifying function blocks that make up control modules and determine the control strategy. The user modifies or debugs a module control strategy by adding, modifying and deleting function blocks, configuring parameters associated with the function blocks and creating a view to new attributes. By defining function blocks and control modules, a user-defined control strategy, application program or diagnostic program is represented as a set of layers of interconnected control objects identified as modules. A layer of the control strategy includes a set of modules which are interconnected in a user-specified manner. A module typically includes an algorithm for performing a specific function and display components which are used to display information to a user.

Abstract: A process controller implements and executes a standard set of function blocks or control functions defined by a standard protocol so that standard-type control is achieved with respect to non-standard-type devices. The process controller enables standard devices to implement the standard set of function blocks and control functions. The process controller implements an overall strategy as if all connected devices are standard devices by usage of a Fieldbus function block as a fundamental building block for control structures. These function blocks are defined to create control structures for all types of devices.

Abstract: A process control system includes a user interface which supports multiple IEC-1131 standard control languages and user-selection from among the control languages. From a single application routine, a user selects a control language from among a plurality of control languages including, for example, Function Blocks, Sequential Function Charts, Ladder Logic and Structured Text, to implement a control strategy.

Abstract: A shear blade assembly (10) on, for example, a tree harvester (12) has first and second blade portions (14,16)which are urged into opposite portions of a tree circumference to cut the tree. A desirable shape of the blade assembly (10) is a concave configuration which minimizes tree damage and efficiently distributes loads through the shear blade assembly (10). An improved method for making the concave shear blade assembly (10) includes cutting blade surfaces (42,44) on a blank (30) and leaving a web (50) between the surfaces (42,44), then depressing the blank (30) to form the desired shape and dividing the blank (30) along the web (50) to form the first and second blade portions (14,16). Making the surfaces (42,44) before shaping and dividing the blade portions (14,16) overcomes problems stemming from distortion of blades which are cut along a curvature following the step of obtaining the desired shape in the blade assembly (10).