Exception handling

Flexibility How are protocol exceptions handled Does it allow for the registration of interim visits What are the business rules for handling required and as-needed forms How easy is it to incorporate protocol or form changes ... 

Exception handling adds complexity to any application. Even if the normal behavior of a component would be easily understood, the presence of exceptions often complicates things dramatically. We want to be able to separate exception specification to simplify the normal behavior specs, but we also want to address the specific characteristics of exceptions, and compose specs containing exceptions. 

By all means, employ defensive specification at appropriate interfaces in your system but make sure that the checking and exception handling are specified and documented as part of the interfaces and not just in the code. 

For example a system can be taken through all its exception handling routines in a simulated environment this might be less practical on a live system. 

However, systems are usually not made up just of computers -rather they will also involve other entities (e.g., devices and humans) which in many cases will not be able to simply forget some of their recent activity, and so simply go straight back to an exact earlier state when told that an error has been detected. Thus forward error recovery (the typical programming mechanism for which is exception handling), rather than backward recovery will have to be used. Each of these complications individually makes the task of error recovery more difficult, and together they make it much more challenging. This in fact is the topic that I and my colleagues have concentrated on these last few years. 

Reducing the cost of sales by removing non-value-added activities (e.g., quality inspections, exception handling, rework, and scrap). 

Capacity and performance reports Event/exception handling reports Help desk call records... 

A. Kumar, and J. Wainer, Meta Workflows as a Control and Coordination Mechanism for Exception Handling in Workflow Systems, Decision Support Systems, 40(1), 89-103 (2003). 

The Virtual Design Team (VDT) is an actor-oriented model for the simulation of product development projects that was created at Stanford University. Early versions of VDT were already able to model actors and activities as well as the information flow between them [599, 604]. In subsequent versions, the different goals of actors, the construction of exceptions, and exception handling [771, 812, 813] were accounted for. A process engineering context was not considered in this model. The methodology does not support the participative creation of simulation models. 

Hagen, C., Alonso, G. Exception handling in workflow management systems. IEEE Transactions on Software Engineering 26(10), 943-958 (2000)... 

Strong, D.M., Moller, S.M. Exceptions and exception handling in computerized information processes. ACM Transactions on Information Systems 13(2), 206-233 (1995)... 

Such systems are an enhancement to various data managanent systems, like LIMS and ELNs. An input certification systan usually does not (1) replace any existing LIMS or quality control system functionality that goes beyond the requirements of calculation, certification, and exception handling of direct inputs (2) create any representation of data beyond textual or tabulated or graphical result entries or (3) contain any third-party calculation or data interpretation. However, such systems may include additional functionality that even makes the development of user interfaces unnecessary automatic form creation. Figure 8.7 shows the outline of the system described in the following. 

Obviously, such a facility becomes very dependent on its computer systems. The overall run-in time takes longer than a traditional factory. The work flow has become less flexible than in manual operation as a consequence of a well-defined work structure controlled by the systems. This in turn enables a very clear exception handling and a highly traceable operation with data and many detailed records to support analysis and follow up on all significant... 

Implementation of proper count measure or exception handling functions in the robot system with certain amount of DoA based on risk assessment... 

Luo Z, Sheth A, Kochut K, Miller J (2000) Exception handling in workflow systems. Appl Intell 13 125-147... 

Mourao H, Antunes P (2007) Supporting effective unexpected exceptions handling in workflow management systems. In Proceedings of the 22nd annual ACM symposium on applied computing, pp 1242-1249, ACM Press, http //www.di.fc.ul.pt/ paa/papers/sac-07. pdf. Accessed 15 Feb 2014... 

Our approach models dependence as a continuous and mutual demand for coordination between teams. The satisfaction of dependencies is real and ongoing activity—coordination that matches the demand for information with the supply of information through coordination by teams. Just as teams have abilities to work, they also have abilities to coordinate, should they allocate attention so. However, an ability to coordinate is not purely determined by their own state, but as a result of their position in the total project architecture with respect to other teams. Poor coordination can trigger reduced quality, exception handling, wait, and rework. As such, the cost of coordination is driven by activity complexity, tacit knowledge, information entropy, and work culture. 

Unsatisfied dependence triggers exception a violation of the constraint (a dependency not being satisfied) triggers exceptional activity, which can lead to not only wait but also errors, quality activity, exception handling and propagating consequences. 

Exception handling Exception handling is the procedures and/or functions that deal with plant or process contingencies and other events which occur outside the normal or desired behavior of batch control. 

Concurrency and synchronization for shared resource Data structure and properties Design assumption and properties Exception handling Behavioral and stmctural view Comprehension by all concerned Verification and validation... 

These define the way exceptions are to be handled. The edge connection with parent has annotation with the type of the exception being handled and an indication of how to continue after exception handling. 

A step can be referred to in more than one location in a process definition. One such reference includes required details, e.g. the step s parameters and resource, and other information about tbe step s exception handling facilities, etc. This reference thus serves to define the step as an abstraction [3]. 

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