cauce - model-driven development of ubiquitous computing environments

PhD. Dissertation

Candidate: Ricardo Tesoriero

Supervisors: PhD. José Antonio Gallud Lázaro PhD. María Dolores Lozano Pérez

Introduction

CAUCE Model-driven Development

CAUCE CASE tool

Conclusions and Future Work

InspirationMajor trends in computingCalm TechnologyContext awarenessRelated Work

Introduction CAUCE MDD CAUCE CASE Conclusions

“The world is not a desktop”

“A good tool is an invisible tool. By invisible, we mean that the tool does not intrude on your consciousness; you focus on the task, not the tool.”

Eyeglasses are a good tool

Mark Weiser, November 7th, 1993

The major trends in computing Mainframe computing (N users 1 computer)

Personal computing (1 user 1 computer) ▪ Internet – widespread distributed computing

(transition)

Ubiquitous computing (N users - N computers)

Mark Weiser and John S. Brown (1997)

“Calm technology engages both the center and the periphery of our attention, and in fact moves back and forth between the two”

Mark Weiser and John S. Brown

By placing things in the periphery we are able to attune many more things than we could if everything had to be at the center

By re-centering something formerly in the periphery we take control of it.

Context Awareness

The Context is any information that can be used to characterize the situation of an entity. An entity is a person, place, or object that is considered relevant to the interaction between a user and an application, including users and applications themselves.

A system is context-aware if it uses the context to provide relevant information and/or services to the user, where relevancy depends on the user's task

Understanding and using context , A. Dey, 2001

There is more context than location, Albrecht Schmidt et al., 1999

Human Factors

Physical Environment

User Information

Social Environment

User Task

Physical conditions

Infrastructure

Location

LightPressure

AccelerationAudio

Temperature

LevelFlikering

Wave-Lenght

Context awareness feature space

Development of a set of applications in a distributed environment

Do not have a fixed architecture Deployed in heterogeneous platforms Connectivity affects how the information is

transported Multiple devices should exchange information

to carry out system tasks Society of entities (collaboration) Location of the entity Knowledge about which task is being performed

by entities to assist them

The capability to define metamodels to match specific characteristics of the system, no matter the level of abstraction it addresses.

Tools for merging and transforming models to reuse information from one layer of abstraction to the next.

Tools to turn these models into source code for different platforms

A Meta Object Facility (MOF) Metamodel for the Development of Context-Aware Mobile Applications Provides contextual model independent of the application domain Manages low level concepts only (event and service) does not support task or role concepts. Does not take into account deployment issues, it is based on SOA

Model-driven Composition of Context-aware Web Services Using ContextUML and Aspects Handles business logic and context-dependent service behavior as two separate concerns Focused in Web applications only (SOA) and services

Towards Context Independence in Distributed Context-aware Applications by the Model-driven Approach Entity vision vs. service vision Low semantic meaning (services)

Context-aware model-driven development by parameterized transformation Different layers of PIMs by parameterized transformations (includes additional information) Context is not characterized, very high level of abstraction that does not provide enough information

about context Towards a Model-Driven Approach for Ontology-Based CAA Development: A Case

Study Step based development Embraces concepts such as Device, Event, Communication, Channel and Activity Does not take into account Roles , Location, etc. Steps are not part of a development process

Model-Driven Development of Context-Aware Services Development process (preparation and service creation phases) Modelling process (PI Service design, PS service design) Low level concepts (events, queries and actions) Lack of task, space, location and role concepts

Managing an Integrated Ubicomp Environment Using Ontologies and Reasoning Good description of the systems Enterprise applications only (client-server) Lack of insulation between context and domain logic, social environment, etc.

An Ontology for Context-Aware Pervasive Computing Environments Space composition Location modelling is not technology independent Notion of agent (entity) No role based functionality Task is taken into account No history is supported at any level

Aspect-Oriented Model-Driven Development for Mobile Context-Aware Computing Combination of AOP and MDD Attached to AspectJ Low level concepts, instead of tasks, roles, spaces, entities and so on

Main goalProposalThe analysis layerThe information layerAnalysis to information layer M2M transformationMapping modelInformation to source code M2T transformation


The main goal of this work is:

“The definition of a semi-formal methodology to tackle the development of Context-aware Applications for Ubiquitous Computing Environments”.

1. Perform a review of the main characteristics of CAAs for UCEs.

2. Perform a review of the most relevant design processes to develop CAAs for UCEs.

3. Define a methodology together with modeling languages to specify the design of CAAs for UCEs based on the characteristics presented in 1.

4. Implement a CASE tool to support the defined methodology allowing the developer to create and edit models conforming metamodels as defined in 3.

5. Define and implement a set of transformations to generate the basic structure of the system source code.

6. Apply the process to a set of scenarios that embraces most CAS features for UCEs to prove the validity of the proposal.

PSM

Platform -Characteristics

PIM

Analysis LayerCAS - Characteristics

Information LayerSoftware - Characteristics

Task modelTask Metamodel

Social modelSocial Metamodel

Space modelSpace Metamodel

M2M

Tra

nsfo

rma

tion

Entity Context modelEC Metamodel

Information Flow model IF Metamodel

Referential Space modelRS Metamodel

M2T

Tra

nsfo

rma

tion

So

urc

e C

od

e

Mapping model

MappingMetamodel

Task model

Space model

Social Model


Analysis layer TransformationInformation layer

Context-aware application feature model

Physical EnvironmentEntity Factors

The goal of this layer is the provision of modeling tools to represent the high-level features of CAAs for UCEs defined in (Schmidt, 1999)

Task modelTask Metamodel

Social modelSocial Metamodel

Space modelSpace Metamodel

Tim

eSocial

EnvironmentLocationInfrastructure

Physical Conditions

Entity Information

Entity Task

The TaMM provides a modeling tool to represent the relationship between tasks and entities that are immersed into CAS for UCEs.

Based on:Petri Nets (Workflows) – To relate tasks and entities

Regular Expressions – To express conditions that relate the TaMM models to SoMM and SpMM models



Workflow Concept * TaMM Concept

Task Task

Condition Condition

Sequential Routing Task dependency

Selective Routing Task dependency

Iteration Routing Task dependency

Parallel Routing Task synchronization/Communication

Process Work session

Token Entity session

* According to the Workflow Management Coalition.

-id : int

-name : string

ContextAwareSystem

-id : int

Task

-id : int

-socialExpression : SocialExpression

-spaceExpression : SpaceExpression

-taskExpression : TaskExpression

-logicExpression : LogicExpression

-dataExpression : DataExpression

Condition

SystemTask

-system_1 1

-systemTasks_1

*

RouteTask

-condition

1

-routeTask1

-system

1

-routeTasks *

TaskOutputCondition

TaskInputCondition

InitialCondition

-system 1

-initialConditions 1..*

FinalCondition

-system

1

-finalConditions 1..*

PreCondition

-system

1

-preConditions *-precondition1

-systemTask 1

PostCondition

-postCondition_1

1

-systemTask_1

1

-system 1

-postConditions *

Join

-outputCondition

1

-routeTask

1

-inputConditions 1..*

-routeTask

1

Split

-outputConditions*

-inputCondition

1

-routeTask1

-inputCondition

1

-routeTask1

System Tasks

Route Tasks

Prefix ConditionAttribute

Metaclass RegularExpression

Template

[So:] socialExpression SocialInstanceSocialSynchronizationSocialAlternative

WordConcatenationUnion

socialInstancesocialExpr , socialExprsocialExpr + socialExpr

[Ta:] taskExpression TaskPerformanceTaskDependenceTaskAlternativeTaskRepetitionTaskAtLeastOnce

WordConcatenationUnionKleene ClausureKleeneClausure +

socialInstance(task)taskExpr , taskExprtaskExpr + taskExprtaskExpr*taskExpr!

[Sp:] spaceExpression SpaceEventSpacePathSpaceAlternativeSpaceRepetitionSpaceAtLeastOnce

WordConcatenationUnionKleene ClausureKleeneClausure +

socialInstance(event,space)spaceExpr , spaceExprspaceExpr + spaceExprspaceExpr*spaceExpr!

[Lo:] logicExpression LogicExpression - (string)

[Da:] dataExpression DataExpression - socialInst(data),...

The SoMM provides the specification of the relationships among individuals and group of individuals that are part of a CAS.

Based on Subset of Penichet’s Organization Structure Diagram (OSD)



Elements

▪ Individual: represents particular entity instances (a token in the workflow during a work session)

▪ Role: represents the characteristics of a group of entities

Relationships

▪ Initialization: represents the “plays” relationship

▪ Specialization: represents inheritance

-id : int

-name : string

Role

Realization

Specialization-target

1

-parent

0..*

-source1

-children

0..*

-realizes

1

-source

1

-isRealizedByIndividual0..*

-target

1 -name : string

Society

-society 1-individuals 0..*

-society

1

-governedBy

0..*

-society1

-generalizations

0..*

-society

1

-realizations

0..* -id : int

-name : string

SocialInstanceInstance

XSocial model

Task model

Social model

Task model

Expresses task alternatives according to entity roles

X

Social model

Task model

Expresses tasks performed by actors belonging to different roles

Social model

Task model

any timeany time

Expresses task concurrency or parallelism between two or more entities

Social model

Task model

same time

same time

Expresses a synchronization points among entities

Social model

Task model

same time same time

The main goal of SpMM is the expression of location aware characteristics of CAS for UCEs

Basic concepts:Positioning reference (space)

Space granularity (composition / grouping)

Space characteristics (generalization)

Time (regular expressions)



PhysicalSpace

Contention

-parent

1

-innerSpaces

0..*

-child1

-container

0..1

Grouping

-id : int

-name : string

Space

VirtualSpace

-groupedBy 0..*

-child

1

-parent

1-contains

0..*

LocartionUnit

-locationUnit 1

Generalization -generalizedBy

0..*

-generalizes

1

-generalizes

0..*

-parent 1

-id : int

-name : string

Universe

-universe

1

-physicalSpaces0..*

-universe1

-virtualSpaces0..*

-universe

1

-groupRelationships

0..*

-universe

1

-generalizations

0..*

-universe1

-inclusions

0..*

Expresses task execution restrictions according to entity location

XSpace model

Task model

Expresses task execution restrictions according entity location history

Space model

Task model

X

Syntax sugar (abbreviations)

How to represent concepts Initialization Pre-conditions Post-conditions Roles vs. Instances Expression calculus Empty expression interpretations

Extensions (to represent CTT constructors)

Comparison to related work Based on Schmidt characteristics we expose the advantages of

this approach compared to related work

Information Flow model

Referential Space model

Entity Context model



The goal of this layer is the provision of modeling tools for designers to represent the context of an entity from the software perspective.

Two views of the system

Inte

r-en

tity

vie

wIn

tra-entity vie

wessential features

contextualfeatures

communicationfeatures

referentialfeatures

Space ReferenceMetamodel

Information Flow Metamodel

Entity CoreMetamodel

Entity Context Metamodel

Software perspective of a CAS

The goal of the IFMM is the description of the information flows among entities of a CASs for UCEs

Basic conceptsEntities involved in the system

The Information flow data exchange through information flows among entities

The Information flow data definition

How Information is delivered

Analysis layer TransformationInformation layer(Inter-entity view)


+incomingFlow(entrada flow : InformationFlow)

-id : int

-name : string

ContextAwareEntity

+flow()

-name : string

-id : int

InformationFlow

Data

InputData

OutputData

BroadcastInformationFlowPointToPointInformationFlow

-data

*

-data 1

-target

1

-incomingInformationFlows

*-source

1

-ongoingInformationFlows

*

-id : int

-name : string

SystemInformationFlow

-system1

-broadcastInformaitonFlows*

-system

1

-pointToPointInformationFlows*

-system

1

-entities*

-flow1

DataDefinition

-definition

1

BinaryOperationDataDefinition

-param1 1

-param2

*

UnaryOperationDataDefinition

-param1

CollectionDataDefinition

-name : string

VaraibleDataDefinition

NotEmptyCollectionDataDefinition

SequenceDataDefinition

AlternativeDataDefinition

TypeDataDefinition ConstantDataDefinition

-name : string

TerminalDataDefinition

Entity

Broadcast information flow

Point to Point information flow

Input data

Output data

Entity

Entity

Entity

Output data

Eve

nt-

dri

ven

Inf.

Exc

han

ge

Po

olin

g

Act

uat

or

The goal of the RSMM is the definition of the runtime environment of the entity contexts in CASs for UCEs

Basic conceptsContext –aware entity (Context-aware entity reference)

Runtime Environment (Referential Space)

Bounding Relationship (Dependence relationship)

Cardinality

Analysis layer TransformationInformation layer(Inter-entity view)


An entity reference can be defined by the Send button

A referential space can be defined by the Login interface

Dependency relationships

Cardinality (a Shopping cart is associated to a single user interface)

Cardinality (the Virtual shopping is composed by many user interfaces)

Session modeling

Information Exchange

Information flow model

Referential space model

The goal of the ECMM is the description of the context that an entity is able to perceive from the environment

Basic concepts:Entity context

Context situation

Context Condition

Data Definition

Analysis layer TransformationInformation layer(Intra-entity view)


Referential space model

Information flowmodel

-context

1

-entity

1

+matches(entrada flow : InformationFlow)

-name : string

ContextSituation

+satisfies(entrada flow : InformationFlow) : bool

ContextCondition

-situation

1

-conditions*

SensingContextCondition

-expression

ContextMemoryCondition

+flow()

-name : string

-id : int

InformationFlow

+incomingFlow(entrada flow : InformationFlow)

+ongoingFlow(entrada flow : InformationFlow)

-id : int

-name : string

ContextAwareEntity

-source

1

-ongoingInformationFlows

*

-target

1

-incomingInformationFlows

*

+incoming(entrada flow : InformationFlow)

+ongoing(entrada flow : InformationFlow)

EntityContext

-context

1

-situations*

EntityCore

-entity 1-core

1

BroadcastInformationFlow

PointToPointInformationFlow Data

-data

*

-flow1

DataDefinition-definition

1

OutputData

-data

1

-name : string

VaraibleDataDefinition

-variables

*

UnaryOperationDataDefinition -parent

1

-param1-informationFlow 1

+match(entrada expression : string) : bool

+update(entrada expression : string)

-name : string

ContextMemory

DictionaryMemory

-memory

1HolderMemory

-context1

-state*

StackMemory

+execute()

-expression

ContextAction

-situation1

-actions

*

-memory1

-action

1

LogicMemory

TimeMemory

Context-aware sensing Pooling

Explicit Initialization

Implicit Initialization

The underlying infrastructure Detailed description of semantics

Services provided to support these models (such as, time service)

Communication infrastructure

How changes are propagated and assimilated by contexts

Memory behavior description

Memory synchronization

How situations are executed

More patterns

Comparison to related work

The analysis to information layer transformation

The information layer to source code transformation + The mapping model



Main goal:

Social model(SoMM)

Space model(SpMM)

Task model(TaMM)

Information Flow model(IFMM)

Referential Space model(RSMM)

Entity Context model(ECMM)

Multi-model Transformation (ATL)

The transformation is composed by:

5 modules to process:▪ regular expressions

▪ the Social model

▪ the Task model

▪ the Space model

▪ a common interface to access these modules

Containing rules and helper functions

Information Flow model(IFMM)

Referential Space model(RSMM)

Entity Context model(ECMM)

Model to Text Transformation (MOFScript) Mapping model(Mapping MM)

Source Code

Main goal:

The goal of this model is the specification of the mapping between information layer models and the source code to be generated

Basic concepts:•Mapping elements

•Devices•Connections

•Definition elements•Protocols•Mediums•Operating systems•Programming languages



-name : string

-version : string

Medium

-name : string

DevelopmentEnvironment

-type : string

-technology : string

-version : string

Protocol

-name : string

-version : string

-revision : string

-profile : string

ProgrammingLanguage

-name : string

-version : string

-revision : string

OperatingSystem

DevicePlatform

-name : string

Platform

ConnectionPlatform

-name : string

Connection

-name : string

Device

-name : string

Entity

-id : int

Edge

ConnectionToDeviceEdge

DeviceToConnectionEdge

-name : string

Information-environment 1

-mediums *

-environment 1

-protocols *

-environment1

-os

*

-environment1

-programmingLanguages

*

-environment

1

-connections *

-environment

1

-devices*

-environment

1

-edges

*

-device

1-platforms

*

-connection

1

-platforms

*

-informations*

-entities *

-source

1

-ongoing

0..*

-ongoing

*

-source

1

-incoming*

-target1

-target1

-incoming*

-language

1

-os

1

-protocol

1

-medium

1

The same PIM can be defined for several PSMs

Underlying infrastructure(Model semantics)

Conceptual Architecture(Class level)

Abstract Framework(Source code)

GeneratedSource

code

Modelled by

Implemented by

Compiles to

CAUCE CASE ToolStudy cases


The CAUCE CASE tool supports the CAUCE model-driven development

Developed using the Eclipse platform (EMF, GMF, etc) Editors: The Social model editor The Space model editor The Task model editor The Information Flow model editor The Entity Context model editor The Referential Space model editor The Mapping model editor

Transformations ATL Model to Model transformation MOFScript Model to Text transformation

Abstract Framework structure

For validation purposes we have defined three scenarios that cover Schmidt CAS characteristics

FeatureScenarios

Light Controller

Healthy Screen

Shared Blackboard

Entity Factors

Information on Entities X

Social environment X

Tasks X

Physical Environment

Physical conditions X

Infrastructure X

Location X

RevisionProposalImplementationContributionsPublicationsFuture Work


The context awareness concept

The ubiquitous computing concepts

UML, MDA, EMOF, OCL, ATL, MOFScript

Formal Methods: Petri Nets Workflows Regular Expressions

Related work on Model-driven development of CAS using MOF Model-driven development of CAS using UML profiles Ontology driven development of CAS

Implementation Eclipse platform (EMF, GMF, etc.) Java Technology

The analysis layer to define the characteristics of CAS to be developed, composed by The Task metamodel The Social metamodel The Space metamodel

The information layer to define the software characteristics of the CAS to be developed, composed by: The Information Flow metamodel The Referential Space metamodel The Entity Context metamodel

An analysis to information layer M2M transformation to turn CAS characteristics into software artefacts

An information layer to source code M2T transformation to turn CAS software characteristics into source code The Mapping metamodel to specify the PSM of the system

The underlying infrastructure to describe model behaviour

A conceptual architecture to support the proposed models

An abstract framework to decouple generated code from implementation

To develop CAS for UCE we have implemented the CAUCE CASE Tool: The Space model editor The Task model editor The Social model editor The Information Flow model editor The Entity Context editor The Referential Space editor ATL M2M transformation between analysis and information layer models MOFScript M2M transformation from information layer models to source

code Abstract Conceptual Framework

We have also generated the source code structure for three study cases covering all CAS for UCE characteristics exposed by Schmidt. The light controller The healthy screen The shared blackboard

MDA Implementation of the CAUCE CASE tool

Ubiquitous Computing 3 metamodels and DSLs to describe CAS for UCE characteristics. 3 metamodels and DSLs to describe software characteristics of CAS for UCE

Verification and formal methods The use of semi-formal methods to model high level characteristics (Petri Nets, Workflows

and Regular Expressions)

HCI Description of interaction elements in terms of regular expressions providing a precise syntax

to describe events

Groupware Some of the methods used to describe CAS for UCE may be used to describe Groupware

systems

AI and Agents The ECMM provides designers to model entity contexts in terms of Horn clauses.

About 20 publications

More than 25% of them were published in journals that belong to Q1 and Q2 (JCR 2008).

More that 50 % of them where published in International congresses

A patent “Interaction device to explore geo-referenced documents” (Spain)

Intra-layer inter-model consistency verification

Adaptation to commercial APIs and programming interfaces

Automatic generation of code for system testing

Verification of Petri Nets properties liveness, bounderness, etc (export to Petri Nets files)

Simulators for the task and flow models.

Metamodel extension to provide the proposed operators in the analysis layer

Implementation of the proposed syntax sugar in the analysis layer

PhD. Dissertation

Candidate: Ricardo Tesoriero

Supervisors: PhD. José Antonio Gallud Lázaro PhD. María Dolores Lozano Pérez