1. Implicit Human Computer Ineraction Through Context
Albrecht Schmidt
Telecooperation Office(TecO),University of Karlsruhe,Karlsruhe,Germany
Personal and Ubiquitous Computing Journal, Springer Verlag London, ISSN: , Volume 4, Numbers 2-3 / Juni DOI: /BF , pp (initial version presented at MobileHCI1999).

2. outline Introduction Implicit Intercation Perception
How Can HCI Benefit from Conext?
Conclusion and Further Work

3. Introduction
Looking at HCI, it is apparent that interaction techniques are limited by the technology available
In this paper we start with the perception of simple concepts and with their exploitation

4. Implicit Interatcion Implicit vs. explicit HCI What is context?
Applicatiobs in context
Identifying implicit HCI
Modelling implicit HCI

5. Implicit vs. explicit HCI
The implicit interaction is based on two main concepts: ‧perception ‧interpretation
Implicit interaction will be used additionally to explicit interaction

6. Implicit vs. explicit HCI
The ability to have perception of the use, the environment, and the circumstances
Mechanisms to understand what the sensors see, hear and feel
Applications that can make use of this information

7. What is context? What is definition of context?
In this paper they propose to regard situational context, such as location or state of the device, as implicit input to the system

8. Applications in context
It can be observed that an application is: ‧running on a specific device ‧at a certain time ‧used by one or more users ‧in a certain physical environment ‧in a social setting ‧to solve a particular task

9. Indentifying implicit HCI
What happens around an application while the application is in use?
Do the surroundings carry any valuable information for the application?
Are there any means to capture and extract the information?
How to understand the information?

10. Indentifying implicit HCI
1. create the set C
2. set D = {}
3. for each Ci ∈ C
define Ai. // accuracy
define Ui. // update rate
identify Si // a sensor device
// that is appropriate
if cost(Si, Ai, Ui) is acceptable then
D = D ∪{( Ci, Si, Ai, Ui)}
next
4. if D ≠ {} then
for each vector Di in D
define a set of application reaction Ri = {(Iij, Rij)}
// Iij is input range, application reaction pairs Iij
// Rij is application reaction
else
// implicit interaction is not used
//(either no condition that are useful or too costly)

11. Indentifying implicit HCI
1:C is the set of surrounding conditions each Ci stands for one condiction
3.If the cost for the identified sensing device Di is acceptable,then the vecter describing to the set D
4.for each of conditions range values that are meaningful are identified and for ranges the reaction is defined

12. Modelling implicit HCI
<!ELEMENT context_interaction
(context , action )>
<!ELEMENT context (group+ )>
<!ELEMENT group (#PCDATA )>
<!ATTLIST group match
(one | all | none ) #REQUIRED >
<!ELEMENT action (#PCDATA )>
<!ATTLIST action
time CDATA ’0’
trigger (enter | leave | in )
#REQUIRED >
Data type definition

13. Modelling implicit HCI
<context_interaction>
<context>
<group match=’one’>
sensor_module.touch
pilot.on
</group>
<group match=’none’>
sensor_module.alone
pilot.pen_down
</context>
<action trigger=’enter’ time=’3’>
pilot.notepad.confidential
</action>
</context_interaction>
Context description

14. Perception Context awareness component Sensor board
Related work on context sensing

15. Context awareness component
The specific contexts in this paper are based on aural information

16. Sensor board
They build a context recognition device equipped with a light sensor, acceleration sensor, a passive infrared sensor, a touch sensor, and a temperature sensor

17. Related work on context sensing
A cup can aware of its state e.g. warm, cold, on table, drinking, moved
A jacket that knows if it is on the hanger or with user is persented

18. How can HCI benefit from context
Output in context
Input in context
Context notepad on a palmpilot

19. Output in context Adapt the output to the current situation
Find the most suitable time interruption
Reduce the need for interruptions

20. Input in context adapt the input system to the current situation
Limit need for input
Reduce selection space

21. Context NotePad on a PalmPilot
On/Off
Fontsize
Backlight
Privacy settings

22. Conclusion and Further Work
The most important thing that system understands as input
What happens around the appliction
How can this be sensed
How to interpret this information

23. Thank you