Requirements Elicitation for the Design of Context-aware

Applications in a Ubiquitous Environment

Dan HongDepartment of Computer Science

HK University of Science & Technology

csdhong@cs.ust.hk

Dickson K. W. CHIUDickson Computer Systems

Hong Kongdicksonchiu@ieee.org

Vincent Y. Shen Department of Computer Science

HK University of Science & Technologyshen@cs.ust.hk

Context-aware Ubiquitous Design ICEC2005-2

Introduction Interaction in the future The trend of human computer interaction (HCI)

Beyond desktop computers Ubiquity – so common: anywhere, anytime that no one

would notice their presence Context become important

Any information that can be used to characterize the situation of entities that are considered relevant to the interaction between a user and an application

Big difference in software design Different requirements under different context

Context-aware Ubiquitous Design ICEC2005-3

Benefits of Context Reduce input cost, effort, and time Provide exciting user experience through new

and convenient features Better support cooperative application in

different environment by, say, context sharing of partners

Context-aware Ubiquitous Design ICEC2005-4

New Software Design Challenges Move from humans vs. computers to humans

vs. context-aware environments Multimodal interactions Multiple devices Specifying and resolving possible conflicts of

requirements Ubiquitous activities are not so task-centric

– more difficult in determining requirements “Knowledge in the world” and sensors

Context-aware Ubiquitous Design ICEC2005-5

Extended Notion of ContextComputing

Contexts User Contexts Physical Contexts

Available devicesCPU

MemoryScreen size

EnergyBandwidth

…

PreferencePurpose

User calendarPersonal

informationFacilitiesDisability

…

LocationTime

DestinationTraffic condition

Physical limitationsWeather

…

Context-aware Ubiquitous Design ICEC2005-6

A Meta-model for Context-aware Requirements Elicitation

User Context

Physical Context

Computing Context

User

Ubiqitous Application

Context RequirementSessionexecute

interact with

Activity Context-aware Capability

matcb

Context

Context-aware Feature

adapts to

Context-aware Ubiquitous Design ICEC2005-7

Requirements elicitation methodology

1. Determine the different target groups of users2. Estimate the typical contexts of these groups (especially those

that possibly affect the system’s interactions)3. For each of these contexts, enlist the requirements specific for

the context.4. Determine the users’ activities during the process of using the

system.5. For each activity, see how different contexts (from step 2) may

impact on its interactions and determine the required adaptation6. For each context-aware feature, detail the desired context-

aware capabilities. 7. Make sure that the context-aware capabilities match and satisfy

all the requirements elicited from step 3. Otherwise, it would mean that some required context-aware feature are missing and we should re-iterate from step 5 to handle those unaddressed requirements.

Context-aware Ubiquitous Design ICEC2005-8

Computing Contexts Consideration

Available devices – multimodal, multiple procession

CPU – device limitation => server side Memory - device limitation Screen size – trans-coding, XSL Energy Bandwidth …

=> Often trade-off required=> Fast technology improvement

Context-aware Ubiquitous Design ICEC2005-9

User Contexts Consideration Preference Purpose User calendar Personal information Facilities (e.g., vehicle, tools, belongings…) Disability Elderly and children users …

=> Requires “intelligence” in software, e.g., matchmaking, ranking, recommendations, etc.

Context-aware Ubiquitous Design ICEC2005-10

Physical Contexts Consideration Location Time Destination Traffic condition Physical limitations Weather …

=> Sensors => “high level” information gathering (e.g., web

crawlers, database interfaces…)

Context-aware Ubiquitous Design ICEC2005-11

A scenario in 2010

Weather report:RainstormTemperature: 10~15

。C

Recommendation:Bring an umbrella

7:00am

Weather report: RainstormTemperature: 10~15

。C

Recommendation:Take an umbrella

Context-aware Ubiquitous Design ICEC2005-12

A scenario in 2010 (2)

9:00am

Good morning, Alice,login finished

Context-aware Ubiquitous Design ICEC2005-13

A scenario in 2010 (3)

11:30am

Reminder:You have an appointment at Restaurant A with Bob at 12:00am.

Where is the way?

Here is the map.Turn left…

Context-aware Ubiquitous Design ICEC2005-14

A scenario in 2010 (4)

1:00pm

Office computer

Personal computer

PDA

Cell phone

Wireless network

Sync. Download

. Done.

Wired network

Let’s make another

appointment

Context-aware Ubiquitous Design ICEC2005-15

A scenario in 2010 (5)

5:00pm

Reminder:Chris is here.

Recommend a restaurant nearby

Recommendation:Restaurant B Alice curry Chris pizza

I love the food

Context-aware Ubiquitous Design ICEC2005-16

A scenario in 2010 (6)

8:00pm

Remote control:Turn on the heat!

Welcome back home, Alice.Turn on the light.

Context-aware Ubiquitous Design ICEC2005-17

Open Issues Natural Interface Relationship and conflicts of various contexts Reasoning model Privacy Evaluation techniques

Context-aware Ubiquitous Design ICEC2005-18

Conclusion Notion of extended context Requirements elicitation for ubiquitous application

design A meta-model and methodology Reconciling user context requirements under

different contexts with context awareness capabilities of the available features.

Analysis of some typical context-aware requirements and design considerations

Context-aware Ubiquitous Design ICEC2005-19

Further and Ongoing work Application in ubiquitous tourist assistance

system MAIS architecture for implementation Three-tier view approach for implementation Ubiquitous collaboration and agent-based

computing

Context-aware Ubiquitous Design ICEC2005-20

Q&A

Thank you!