A major success factor of business process redesign projects is the extent to which the organisation members themselves - both management and staff - are actively involved in the redesign project. One way to assess different redesign alternatives with respect to the project goals is to model these alternatives and subject them to a simulation study. Visualization and animation of the simulation models can provide insight into both the structure and the dynamics of the modelled alternatives. Effectively presented, visualization and animation enhance the involvement of the project members in the assessment and validation of the proposed redesigns.

To support communication among all participants in the BPR project, we advocate an integrated presentation of redesign alternatives, visualized simulation experiments and the results of simulation studies in a single active document. In this paper we describe a framework enabling such integrated presentations by allowing the embedding of simulation models and experiments in hypermedia documents.

Keywords and phrases: Business Process Redesign, Logistics-based Business Modelling, Discrete Event Simulation, Hypermedia, Active Documents, Web.

Contents

  • Introduction
  • Business Process Modelling
  • Software Support for BPR
  • Example -- Requests for Loans
  • Embedding BPR in Hypermedia
  • Conclusions
  • References
  • Appendix
  • Introduction

    Business Process Redesign (BPR) is a method to perform organizational change. Instead of functions and departments it takes business processes as the main subject to redesign the way work is done in a particular organization.  [Davenport90,Davenport93,Davenport94,Hammer90,Wastell94] Davenport and Short  [Davenport90] argue that business process redesign should be combined with the capabilities of Information Technology (IT). They show that IT can play two roles in BPR: on the one hand it is an enabler of new process structures. An example would be the use of expert systems to assist bank clerks handling loan requests. On the other hand IT can provide support for the implementation of new process designs. By, for example, simulating the logistic aspects of the redesigned loan request process.

    By modelling different redesign alternatives and subjecting them to simulation studies the participants in the business process redesign project can assess the alternatives with respect to the redesign project goals. Possible goals include cost reduction, lead time reduction, raising output quality and improving the quality of worklife. Visualization and animation of the simulation models can provide insight into both the structure and dynamics of the modelled alternatives and thus improve decision making.

    In this paper we advocate an integrated presentation of redesign alternatives, visualized simulation experiments and the results of simulation studies in a single active document. Our approach allows authors to write hypermedia documents with embedded simulation models and experiments. These documents can be viewed on the Internet, or on a company Intranet, using an adapted Internet Web browser.

    Our system has been implemented using the hush  [Hush] hypermedia framework developed at the Vrije Universiteit. This framework provides support for multimedia user interfaces, a discrete event simulation library  [SIM] and embedding of applications in the Web  [Applications,Animate]. To model business processes we use Logistics-based Business Modelling (LBM)  [Gerrits95]. The class library BPSIM (Business Process Simulation) facilitates the modelling of business processes using LBM and provides additional support for embedding and running simulations on the Web.

    Structure

    In the following sections we will introduce the concepts underlying logistics-based business modelling and we will describe the software support for simulating business processes, in particular the classes provided by the BPSIM library. We will present an example illustrating the construction of a business process model and its visualisation in a hypermedia environment. Then, we will briefly characterize the hypermedia environment and its relation to the World Wide Web. And, finally, we will discuss the merits and limitations of our approach.

    Business Modeling

    Dramatic improvements in business performance and productivity may be achieved by critically examining some of the rules that govern a business process. Business Process Redesign (BPR) is the generic label for many emerging methodologies aimed at producing these improvements. Re-design implies that the current state of affairs is no longer acceptable and can no longer be refined or evolved. The BPR perspective demands that its users understand the nature of the business they are in, and the processes that can be re-engineered. In order to achieve this understanding, part of the BPR approach is to map out an organisations processes. The model created during this phase is used to communicate the BPR team's ideas and will also be used to plan changes to the current processes. Following Davenport and Short  [Davenport90] we define a business process as "a set of logically related tasks performed to achieve some well-defined business outcome". It is important to note that business processes have customers that, somehow, receive the outcome of these processes. Also, to stress the functional nature of business processes, it may be remarked that business processes often transgress departmental boundaries within an organization.

    Despite the importance of qualitative assessments in BPR  [Hammer90], for modelling we favor a more quantitative approach for which we provide support by means of a simulation library (BPSIM) based on the Logistics-based Business Modelling method (LBM) presented in  [Gerrits95].

    Logistics-based modelling allows for analysing the time spent in executing a business process. The product lead time is defined as the time that passes between the moment a customer orders a product and the moment a product is delivered. In more detail, we can distinguish between processing time (the time actually worked on a job or operation), queue time (the time a jobs waits for a resource to become available), setup time (the time that passes between the moment a resource becomes available and the moment work on the job is started), wait time (the time that is spent waiting for another job to complete), and transport time (the time that is needed to move a job from a resource at a certain location to a resource at another location).

    For a particular model, measurements may be obtained by running a series of simulations. Based on an analysis of the simulation results alternative models may be proposed. For example, when the setup time for a job is relatively large, combining jobs into a single task for an employee may be more efficient.

    Modelling Business Processes

    The LBM method offers a number of primitives, with associated graphic icons, from which a business process model may be constructed as a network of resources connected by transport arcs. The primitive entities offered by LBM are: Operations are atomic in the sense that wait time, queue time and transport time may not be part of an operation. Only setup time and process time are part of an operation. Tasks are introduced to allow for a series of jobs or operations to be processed, for example by one employee, in order to reduce the setup time needed. Transport entities represent the time it takes for information to flow from one resource (that is operation or task) to another. Transport implicitly defines the sequential structure of a process. However, duplications of information, and consequently parallel operations, are allowed.

    In addition to the primitives mentioned above, LBM allows us to characterize

    Also, employees may need additional means to engage in an operation or task.

    Process Simulation

    The BPSIM library is an extension of the simulation library SIM  [SIM]. SIM is a C++ library offering classes supporting discrete event simulation, based on standard simulation techniques  [Watkins93]. In discrete event simulation, the components of the model consists of events, which are activated at certain points in time and in this way affect the overall state of the system. The simulation library consists of the following classes: The SIM library is integrated with the hush library, which may be used for defining a script interface to the simulation package, for developing a graphical user interface and for visualising simulation models.

    The library BPSIM

    The classes provided by the business process simulation library BPSIM reflect the entities provided by the logistics-based business modelling method LBM. On a somewhat more abstract level, a business process simulation consists of data, flowing through the process and different handlers -- datahandlers -- performing some action on the data, such as transportation or specific operations.

    Accordingly, BPSIM provides two base classes underlying the classes corresponding to LBM entities:

    Note that LBM contains no symbol for data as it only depicts the objects that handle the information. The following classes are derived from the datahandler class: operation, transport, waitqueue, choice, archive, and external agent, which realize the corresponding entities in LBM.

    An operation takes time, and is executed by an employee. Sometimes an operation results in more than one outgoing dataflow, for instance when it issues a request for additional information from a different department.

    A waitqueue functions as a regular queue if it has one incoming dataflow, i.e. transport. When there are more incoming flows, it functions as a synchronized queue. Data from one flow is not passed on to the next datahandler until the data from the other flow has arrived. This happens for instance when work on a case cannot continue until additional information has arrived.

    An external agent can either generate data according to some random number distribution, or take data, process it and pass it on to the next datahandler. In the latter case the agent functions as a black box: we only care how long the processing takes, not how it is exactly performed.

    In addition, BPSIM offers the classes means (which can be used to model resources that are necessary to perform certain operations), and employee (which models the different people that perform the operations).

    As one can see, the entities task and organization unit from LBM have no specific counterpart in BPSIM. The reason for this is that having no other datahandler between two operations already implies those operations belong to the same task. Consequently they are executed with no time in between and by the same employee. Also, the fact that tasks are executed in different organization units does not add any information that changes the behaviour of the simulation. If it takes time to transport information between different units, then that time can be represented by the object of class transport between those units.

    For the gathering and analyzing of results, the SIM classes histogram and analysis are used. The class agent, for example, can be given a histogram to track the lead time of data it has generated.

    A script interface for BPSIM

    Employing the facilities of the hush library a script interface has been defined for BPSIM that allows the user, that is the designer of business models, to construct and run business simulation models with a short turn around time.

    Each class in the BPSIM library corresponds to a command in the script language. As illustrated in the next section, script commands result in a graphic representation of model, which may be displayed in a Web page as an applet.

    Requests for loans

    Now let us take a look at an example business process model based on the objects made available in BPSIM. The example will detail possible situations before and after business process redesign has taken place.
    Current Situation:
    Our first model, which represents the current situation, consists of a client producing, for example requests for a loan at a bank. The requests are initially handled by a clerk whose task is to send requests for amounts greater than 10000 dollars to the boss. The boss, whose task is to approve or denigh the loan, sends the result back to the clerk for processing. If the amount is less than 10000 dollars, the clerk has authority to process the request himself.
    Redesign Alternative:
    In our second model, which is the result of a redesign effort, requests are handled by a clerk who enters the data into a computer. The computer now makes the decision as to whether the loan is approved - for loans of value less than and greater than 10000 dollars. The clerk then passes the results on to another clerk for the task of dispatching loans.


    slide: Presenting a Redesign Alternative

    Figure 1 shows the visual representation of the model resulting from the redesign effort, embedded in a Web page. In addition to the model, the page contains some results obtained by running a simulation. For example, the text indicates that an employee is busy handling incoming requests only 33% of the time. The histogram depicts the distribution of the lead times of incoming loan requests, that is the time that passes between receiving a request and giving an answer. The Web page further contains a button to start a simulation run, a description of the model and links to alternative models.

    The script

    Below we show some fragments of the script.
      histogram leadtimes
      agent client generate leadtimes
      client -duration 60 poisson
      transport t1 
      t1 -duration 20
      employee clerk
      operation receive clerk
      receive -duration 20.0 5.0 normal 
      
    In this fragment a histogram for recording leadtimes is created as well as an agent generating requests and a transport to a clerk handling the requests. The duration of the agent is specified using a poisson distribution with \lambda = 60. The clerk is declared to perform a receive operation, the duration of which takes values from a normal distribution with \mboxmeans = 20 and \mboxstandard deviation = 5.0.
      client -next t1
      t1 -next clerk
      
    The fragment above shows how the various components of a model (for this fragment the agent, transport and employee) may be connected.

    After defining the components of the model and their connection a simulation may be started by pressing the start button. If desired, users may change the parameters concerning for example setup and wait time, to explore the various scenarios a model has to satisfy.

    The environment

    Given the importance of participant communication in a business process redesign effort, embedding business simulation models in hypermedia provides in a natural way the information context needed for exploring alternatives and taking decisions. With Intranets becoming more popular, the World Wide Web has proven to be a popular access point for many applications.

    The hush library and its extensions offer a rich environment for developing hypermedia applications and dynamic Web documents  [Applications].

    The hush library originated as a C++ interface to the GUI scripting environment provided by Tcl/Tk  [Hush]. Tcl/Tk offers an extensible script language with powerful graphics and window programming utilities. A number of extensions to hush have been written, including the SIM and BPSIM libraries as well as libraries encapsulating multimedia facilities. The hush Web component provides a collection of (inline) data viewers for the hush Web browser. It supports full SGML and style sheets to specify dynamic layout properties in a declarative way  [Animate]. Also applets are supported, which are Tcl/Tk scripts augmented with the functionality of hush applications. Applets are the building blocks of active Web documents.

    By defining a script interface for application-specific C++ classes, application functionality may be embedded in a Web page as an applet. As illustrated in the example, our approach to providing hypermedia and Web support employs this feature, both to reduce the time involved in modelling and to present a graphical representation of the model and its execution to the user.

    Conclusions

    As observed by Wastell  [Wastell94] organisational change is a ``highly threatening and stressful experience for many participants and that high levels of stress can have a pernicious effect on individuals, group processes and organizational learning''. Hence, directly involving the users in the modelling phase of the BPR project may be an important step towards capturing the human aspects that are necessary for the production of an optimal model. It may also help to lessen the anxiety of employees.

    Our contribution in this area is to provide support for an information context that encompasses both technical and social dimensions of the re-engineering effort. On a technological level, we advocate the use of business process simulation. Nevertheless, to accomodate the social aspects, we support the visualisation of such models and their integration in an arbitrarily complex information context, such as the World Wide Web.

    As concerns the limitations of our approach, we wish to remark that we have only realized part of the visualisation and animation facilities that we consider desirable. Furthermore, in our current realization the user is required to use the hush Web browser, instead of a popular browser such as Netscape.

    Developing visualisation and animation support for simulation models is a topic of ongoing research. To deal with the problem of accessibility we have to adopt a new technology, that is use for example Java, or develop a Netscape plugin for hush applications.