Experiencing Process Flexibility Patterns with Alaska Simulator

Abstract

Alaska Simulator is an interactive software tool developed at the University of Innsbruck which allows people to explore di erent approaches to process exibility by using a familiar metaphor, i.e., travel planning and execution. In addition, Alaska Simulator is used for studying research questions in the context of business process management and other related elds. For this, Alaska Simulator provides integrated support of di erent approaches to process exibility in terms of decision deferral patterns, which all allow interleaving process modeling with execution and provide mechanisms for e ectively dealing with uncertainty. The biggest challenge for users of such exible systems is to nd the right balance between pre-planning activities and keeping options open. To address this challenge Alaska Simulator allows safe exploration and systematic investigation of how much pre-modeling is needed under different circumstances.

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1 Introduction Alaska Simulator has been developed to support the teaching of di erent approaches for process exibility and to investigate their strengths and weaknesses through the execution of controlled experiments. Due to the many similarities between modeling and executing business processes and journey planning Alaska Simulator uses a journey as a metaphor 1. The used metaphor is not only helpful to explain di erent exibility approaches to people without signi cant experience in business process management, but is also an attractive context to be engaged in, thus increasing the willingness of subjects to participate in experiments. In the following, we describe the di erent approaches for process exibility supported by Alaska Simulator (cf. Section 2), participating roles in the form of personas [ 1 ] and how they can work with and bene t from Alaska Simulator (cf. Section 3). 1 For a detailed description of the journey metaphor visit the simulator's website: http://www.alaskasimulator.org 2 Process Flexibility Support in Alaska Simulator In today's dynamic business world the economic success of an enterprise depends on its ability to react to changes in its environment in a quick and exible way. To address this need several approaches for exible process support have been proposed. All of these approaches address the problem of process change either through structural modi cations of a prede ned work ow (e.g., adaptive work ows [ 2 ]) or the introduction of more exible execution models, which allow users to defer decisions regarding the exact control- ow to run-time (e.g., Late Binding, Late Modeling or Late Composition, for an overview see [ 3 ]). Common to all these approaches is the fact that they relax the strict separation of build-time (i.e., planning) and run-time (i.e., execution), which has been typical for plan-driven planning approaches as realized in traditional work ow management systems (cf. Figure 1). They allow for a more agile approach by closely interweaving process modeling and execution.

No exibility for changing the process de nition during run-time is supported by a traditional work ow system, i.e., the modeled process schema cannot be altered at run-time. The Late Binding pattern provides exibility by allowing for the introduction of a placeholder during modeling. At run-time the user de nes the content of the placeholder by selecting the most appropriate process fragment from a pre-de ned set. Late Modeling further extends the concept of Late Binding by enabling the user to model the content of the placeholder during run-time { the activities users can insert may be restricted when creating the process Dmoifdfeelr.eLnatteFCleomxipboisliittiyonAopperrsoathcehheigshest degree of exibility58by allowing the user to exibly compose the businesss process at run-time and to freely switch between process modeling and execution.

h g i H tr o p p u S r e s U fr o d e e N w o L Low

Late Composition

Late Modeling

Traditional

Workflow

Support

Late Binding

Degree of Flexibility

High

Alaska Simulator is the rst tool providing integrated support for all of these decision deferral patterns fostering the systematic comparison of their strengths and weaknesses in a training environment.

Experiencing Process Flexibility Patterns with Alaska Simulator 3 Major Roles and Main Functionalities AST consists of three major components: Alaska Simulator, Alaska Con gurator and Alaska Analyzer. This section describes participating roles in the form of personas [ 1 ] and explains how they can interact with and bene t from the Alaska Simulator Toolset (AST). { Steve Student: tests and analyzes his planning behavior with the simulator and explores how much planning is just enough under di erent circumstances { Rose Researcher: investigates the strengths and weaknesses of di erent approaches to process exibility using the simulator (for example see [ 4 ] for the results of a recently conducted experiment using Alaska Simulator) { Isabel Instructor: demonstrates the di erent exibility approaches using a journey as a metaphor and explains the major di erences between these techniques The major features of AST are as follows: { Design journey scenarios: Alaska Con gurator allows researchers and instructors to design their own journey scenarios including locations, actions, events, constraints as well as the degree of uncertainty (cf. Fig. 3) { Plan and execute journeys : Alaska Simulator allows to plan and execute journeys using di erent approaches to process exibility (cf. Fig. 2) { Log journeys: Each step that is performed while planning and executing a journey is logged by Alaska Simulator for later investigation and detailed analysis { Replay journeys: To enable interactive analysis of planning behavior, journeys can be replayed step by step in Alaska Simulator { Analyze journeys: Instructors and researchers are supported in analyzing the journeys after a planning session has been conducted with Alaska Analyzer Alaska Simulator, including a test con guration, extensive documentation and screencasts can be downloaded from http://www.alaskasimulator.org. Alaska Con gurator and Alaska Analyzer are available to interested parties upon request. For detailed information on the results of a controlled experiment which was conducted using Alaska Simulator we refer to [ 4 ].

Incomplete information prior to execution is a characteristic of both journeys and highly flexible business processes and is best handled by waiting until more information is available (cf. Section 2.2). The outcome of a travel activity is not predefined, as it can vary depending on the weather conditions during the journey. When composing a concrete business case, different constraints like selection constraints, ordering constraints or resource constraints have to be considered (cf. Section 2.3), as similar constraints also exist when planning a journey (e.g., mandatory activities, dependencies between activities, opening times, budget)1.

Barbara Weber , Stefan Zugal1, Jakob Pinggera1, and Werner Wild2 tool for planning and executing journeys (i.e., the business process); the Actions View c   (3) lists availabFlieg. a3cdteiopinctss. tThehgeraCphoicnasltursaeirnitnsterVfaiceewof (t2he) AolnasktahSeimruiglahtotr.tUosperscorner shows constraints rceasntrciocmtpinosge tthheeir jinoduivrnideuya.l tTraovealpsslainstbythderagugsinegr aivnaildabelveealcotpioinnsgfroamctohnesistent plan, the ProblemsaAvvaVaiililaaebbwllee a(At5c)atioppnaosrtinVictuieslwaro(ul3o)tcaoitnniotconotinnhsetihtsretaevmnealcppiel(as4n)a.(nE1)dx.isActicontngiosnctosrnaasrtiernatuinstvusaiolalyrleaotdniiolsy-ns. The Map View (4) o eprlsayaend ionvtehrevCieownstorafinatllVlioewca(2t)ioannds haanvde tionbdeiccaontseisdetrhedewthreanvecolemrp'osscinugrarent location. concrete journey. After each user action, the journey is validated and the user is informed about any constraint violatio ns (5). d   e   f   Fig. 3. Alaska Con gurator allows users to compose journey con gurations including actions (1), locations (2), constraints (3+4) and events to set up controlled experiments

References

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4. Weber , B. , Reijers , H. , Zugal , S. , Wild , W.: The declarative approach to business process execution: An empirical test . In: Proc. CAiSE'09 . ( 2009 ) 470 { 485