PERSONALISED AMBIENT INTELLIGENCE IN BUILDINGS
VIA CONTEXT-AWARE AGENTS
Soi Luong
Technologies for Sustainable Built Environments
University of Reading, Department of Physics, Reading, RG6 6AF, United Kingdom
Samuel Chong
Capgemini U.K.
77-79 Cross Street, Sale, M33 7HG, United Kingdom
Keywords: Context-Aware Agents, Intelligent Buildings, Hawthorne Effect, Intelligent Agents, Ambient Intelligence.
Abstract: One of the concepts of intelligent buildings is to maximise occupant comfort. Optimising the environment
for a single occupant is a simple procedure but for a shared environment presents a difficult challenge. This
paper proposes the use of context-aware agents that utilises the Hawthorne Effect theory for providing and
resolving the conflicting preferences in a multi-tenant building environment. This is an ongoing research
and the solution consists of a multi-agent framework for interacting with the environment and learning the
occupant’s preferences through a user-interface. The agents will learn the occupant’s preference using a
simple heuristic question and answer method and perception through networked sensors. The Hawthorne
Effect solution attempts to resolve the conflicting requirements by fluctuating the heating and lighting
during the course of the day to meet all occupants preferences.
1 INTRODUCTION
A typical building has a set of common services
such as heating, ventilation and air conditioning
(HVAC) systems, lighting, security systems and
electrical technologies. All or most of these services
are essential to provide a habitable environment that
is both comfortable and satisfies occupant needs.
The underlying components of these services are
sophisticated but can be simply operated by a switch,
automated or programmed to run at a certain time of
the day.
Large organisations have many offices to
accommodate their employees. They are required to
provide an ergonomic environment that is compliant
with legislation and regulations. It is also of business
interest that they configure the internals of their
buildings to maximise employee productivity. For
example, an office is populated by occupants and
computer systems but they must also have bright
reflective lighting, central heating systems to keep
the occupants warm during the winter periods, air
conditioning systems to keep the temperature and
humidity levels low during summer periods and
ventilation to extract CO
2
from the environment.
These services must be fully functional when an
occupant is present in the office. However, in a
multi-tenant office the services need to be shared
and the environment is most likely unable to meet
everyone’s preferences.
The concept of intelligent buildings was
introduced over 20 years ago and its common
purpose is to ‘maximise occupant comfort’ and
‘minimise life-cycle cost’. The purpose suggests that
we should think about what the occupants want and
how intelligent buildings can help an organisation.
In the following, we examine the use of context-
aware intelligent agents to provide personalised
heating and lighting services for human
surroundings in a shared office environment.
This is an ongoing piece of research which
focuses on examining the agent methodologies
which are applicable to maximising occupant
comfort. A solution has been proposed and a
prototype has been built based on the study of
17
Luong S. and Chong S.
PERSONALISED AMBIENT INTELLIGENCE IN BUILDINGS VIA CONTEXT-AWARE AGENTS.
DOI: 10.5220/0003258900170023
In Proceedings of the Twelfth International Conference on Informatics and Semiotics in Organisations (ICISO 2010), page
ISBN: 978-989-8425-26-3
Copyright
c
2010 by SCITEPRESS Science and Technology Publications, Lda. All rights reserved
related work and current research of intelligent
agents and multi agent systems. This paper discusses
our contributions to Personalised Ambient
Intelligence by presenting a heuristic question &
answer interface and the inclusion of the Hawthorne
Effect theory.
The paper is presented as follows. In section 2,
we discuss the problems associated with this
research and construct scenarios for the purpose of
validation. Section 3 contains an analysis of the
related work by academic research and other
pioneering projects. We look at our proposed
solution in Section 4. Finally, we critically evaluate
and conclude the paper in Section 5.
2 AMBIENT INTELLIGENCE
IN BUILDINGS
Raising the topic of ambient intelligence one would
certainly envision an array of intelligent devices
seamlessly integrated with the environment. The
devices know who you are, react to your actions and
the environment, and anticipate your desires before
you even show it. In reality, ambient intelligence
involves ubiquitous computing, user profiling and
intelligent systems (Shadbolt, 2003); this denotes the
core concept of utilising inexpensive, networked
context-aware devices simultaneously with human-
computer interaction and behaviour perception for
pattern recognition to construct human requirements.
Our approach comprises of three research
objectives for designing a system that is ‘seamlessly
integrated’ with the devices and the environment.
2.1 Ambient Intelligence
The system should govern the electronic network
that is sensitive to occupant’s needs. The problem
with existing building services is that when it is
required the occupant has to operate it themselves
and they may forget to turn if off when they leave
the building. Personalisation is required as each
tenant has different preferences in which they may
want to configure their desired environment. Rather
than having the occupant repeatedly informing the
system what they want, it should be able to
anticipate and change the environment accordingly
by continuously recalibrating itself (Shadbolt, 2003).
2.2 Context Awareness
The building services must have the ability to sense
and react to the environment through devices, such
as, RFID readers for sensing human presence, a
thermometer to read the room temperature, etc. But
such devices must have a level of sophistication to
perceive a situation or human factors: social
environment, i.e. co-location of others and group
dynamics (Schilit, 2004).
2.3 Intelligent Agent
Intelligent agents are the main focus of the
simulation which should be responsible for
observing and reacting to provide a dynamic
environment through a context-aware interface.
Intelligent agents in buildings act autonomously and
discreetly from occupants requiring initial training
and calibration to accumulate its knowledge base of
user profiling to provide personalised services in an
office environment.
Figure 1: How agent interacts with environment through
sensors and effectors.
Intelligent agents are categorised into four classes
based on the degree of perceived intelligence and
capability:
1. Simple reflex agent
2. Goal-based agent
3. Utility driven agent
4. Learning agent
Simple reflex agent methodology is based on a
condition-action rule: if certain criteria meet the
condition then it will perform an action. Other
complex agents, such as, goal-based and utility
driven agents behave in a similar fashion to find
possible solutions to achieve its goal. The actions
performed are repeated until it produces the desired
result or alternatively attempts other methods. Utility
driven agents are more selective about which
method to undertake and choose the best possible
method to achieve a goal (Kozma, 1998). A learning
agent has the ability to act independently and learn
ICISO 2010 - International Conference on Informatics and Semiotics in Organisations
18
from past experience. It needs to be able to “adapt its
behaviour according to user needs” (Pissinou, 1997).
Each agent is able to assess the current state of the
environment and perform appropriate actions but a
learning agent has the ability to learn from a
dynamic context, for example, perceiving the social
environment in a multi-tenant office, maintaining a
history record of human behaviour and adapting to it
to provide a personalised environment.
For this research, we evaluate three scenarios for
the purpose of constructing a simulation:
1. User-interaction and personalisation
Occupants require a method of communicating
with the system that manages the building
services. Normally, the occupant uses the light
switch on the wall to activate the lights, a
thermostat to control the heating or an air-
condition control panel to provide cool air both
of which requires the occupant to enter a value in
degree Celsius or Fahrenheit. In order to train a
computer, a user-interface is essential to capture
the occupant’s preferences.
2. Shared services
In an office environment, HVAC and lighting are
shared amongst the occupants. The HVAC
operates as a single unit to regulate the room
temperature. Lighting is slightly different as
there could be several switches for operating
lights on separate networks. It would be
beneficial if these services could operate
independently to provide a personalised service
and minimise energy expenditure. For example,
the computer system can set the four air
conditioning systems in the office to operate at
different temperature levels.
3. Social environment
There are scenarios where all occupants may
gather in a room to hold meetings. Prior to
entering an assistant to the organiser prepares the
room five minutes before the meeting begins to
ensure the room is at an acceptable temperature
and the lighting is turned on for the attendees.
The co-location of the occupants and group
dynamics in this situation suggests that the
computer must be able to handle a variable
context and prepare a personalised service in
anticipation.
The scope of this project is to implement a software
agent that intelligently manages the heating and
lighting of a building office environment. Simulated
devices include sensors, radiators, air conditioning
and lights.
3 RELATED WORK
Intelligent Buildings is a very broad area of research
that comprises of many components which are
grouped under four categories: “facilities
management, information management, connectivity
and overall control” (Flax, 1991). However, this
paper focuses on facilities management of heating
and lighting in the building.
3.1 Intelligent Agents/Multi-Agent
Systems
There are four classes of intelligent agents as
discussed in Section 2 and they each act and perform
differently from one another. To summarise, the four
classes of agents are capable of simply operating by
condition-rules, reiterate the best results, be selective
about the best results and learn from their
environment. The learning agent appears to be
suitable for our simulation as one of the main
requirements is personalisation.
Figure 2: Intelligent Agent Framework.
Typically, this type of agent has a data repository for
recording knowledge. But, the definition of learning
in this scenario would be a domain-specific
knowledge base and not an agent that utilises
learning techniques, such as, neural networks and
genetic algorithms (Chen, 1995). For this project,
the intelligent agent keeps a repository of the heating
and lighting preferences of each user.
There are many limitations with using a single
agent to be the user-interface, negotiator, processor
and performer. With the introduction of multi-agent
PERSONALISED AMBIENT INTELLIGENCE IN BUILDINGS VIA CONTEXT-AWARE AGENTS
19
systems, the agents interact and negotiate with each
other to solve complex problems which a monolithic
system, such as, a single agent cannot do. Multi-
agent systems is beneficial in the scenario of not
only managing heating and lighting service but user-
interaction, sensors, effectors from having their own
agent and a negotiation mechanism can be applied
between the agents to solve disputes (Mo, 2002).
In a multi-agent system one agent should manage
the sensors: constantly observe for the co-location of
occupants, anticipate user behaviour, analyse social
activity, logging user check-in and check-out time;
another agent can focus on energy savings and
building controls; and one more agent can manage
the interaction between the user to ensure the user
preferences are recorded and sent to an agent that is
responsible for controlling the services.
3.2 Occupants Comfort
The human comfort zone can be used to describe the
occupants’ comfort. The optimal body temperature
is at 36.8
o
C (Elert, 2005) and the “occupant’s
thermal comfort is dependent on the temperature,
humidity and air of the room” (Meier, 1994). Some
researchers suggest that heating affects the comfort
level and productivity of an occupant that is subject
to heat stress if comfort zones are not met. Lighting
also has an effect on working productivity (Beld,
2001), as the age of the occupant increase their
requirement for lighting also increases. The light
intensity varies amongst people and occupants
accept that having strong light intensity in an office
is very important because a lot of creative work is
performed and lighting should “guarantee sufficient
visual performance for tasks concerned” (Beld,
2001).
Some of the more recent work like MASBO
(Qiao, 2006) uses an approach that balances energy
efficiency, occupants’ preferences and priority to
achieve occupant comfort; Conflict Resolution
Architecture is presented by (Lee, 2008) where they
try to solve the conflicting requirements of
occupants using a “priority” and “privilege-average”
approach. ZhengChun Mo (2002) formulated an
equation for maximising occupant comfort and
minimising electricity costs when one of the agents
receives a conflicting request. This sort of conflict
resolution is only made possible in a multi-agent
system because a single agent would not have
enough parameters for negotiating with itself: a
single agent will serially perform energy
consumption calculations and send commands to the
effectors, but it would not raise the issue of whether
that command is cost effective.
4 CONTEXT-AWARE AGENTS
FOR PERSONALISATION IN
INTELLIGENT BUILDINGS
The metrics for identifying temperature is generally
Celsius (°C), a common measurement in the United
Kingdom, and Fahrenheit (°F). The illuminance of a
light bulb is dependent on the energy used and the
brightness can be measured by the amount of
wattage it consumes. Another metric used to
measure the light emittance is LUX. But, in an office
environment, do the occupants know how bright
their lighting is in LUX? Obviously, they know what
temperature the room is at because of a thermostat or
a thermometer but does it display the actual
temperature: different room dimensions have
different temperature readings which also depend on
where the thermometer or thermostat is placed.
Overall, the occupants are concerned about whether
all the lights are working and are very bright, one
might find the lights too bright but will have to
compromise because they cannot change it, and that
if the temperature is not comfortable then they will
either continuously adjust the thermostat until they
get the desired result or use the air-conditioning.
4.1 User-Interface
The user-interface is designed with a user-centred
approach to minimise user intervention and also
taking into consideration the usability of the system
that the occupants are going to ‘train’ and calibrate
via heuristic question and answer methodology. An
expert system called MYCIN utilised this
methodology to solve medical problems: a series of
closed-questions were used to identify illnesses
(Buchanan, 1984). Heuristic question and answer
can be used as the training simulation to question the
user if they are satisfied with the temperature or
lighting and to fine tune the services until the user
gets their desired results.
ICISO 2010 - International Conference on Informatics and Semiotics in Organisations
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1: Is occupant satisfied with temperature/lighting?
2: Increase or decrease the temperature/lighting?
Figure 3: Training Simulation Data Flow Diagram.
The intelligent agent can then learn the occupant’s
preferences by recording the results of the training.
This eliminates the purpose of displaying the
Celsius/Fahrenheit and LUX values because the user
can assess and feel the environment changes in real-
time therefore keeping the user-interface as simple
as possible.
4.2 Multi-Agent System & Hawthorne
Effect
An office environment has many heaters, air-
conditioning and lights. These services can be
segregated into zones where each zone will have a
certain number of occupants. Each zone has a set of
agents for handling the interaction and
communication with its occupants via a user-
interface, sensors to perceive human actions and co-
locations, and managing services within that zone.
The multi-agent system makes up a network of
intelligent agents that is used for the intelligent
building architecture.
UI: User-
Interface
1: User Agent
2: Effector
3: Local
Agent
4: Sensor Agent
5: Environment
Figure 4: Multi-Agent Framework.
The diagram above shows our multi-agent
framework design for the simulation. As the sensors
and effectors are simulated these has been included
in the User Agent and Effector component, as shown
in the diagram in which they communicate with the
User-Interface.
To tackle the problems of sharing services
between occupants as well as trying to maximise
occupant worker productivity the Hawthorne Effect
suggests varying the environment so that it meets all
the occupants’ needs (Draper, 2008). The intelligent
agents will not only calculate the occupant’s desired
temperature and lighting but can also adjust them
both accordingly at consistent intervals. For example,
if one occupant’s preferred temperature is at 24°C
and another occupant has a preferred temperature of
24.5°C then the intelligent agent adjusts the
temperature to fluctuate between 24°C and 24.5°C
so that both occupants are satisfied at several
durations within each hour.
The Hawthorne Effect has been criticised by the
Maslow’s Hierarchy of Needs which states that
increase productivity is dependent on the
individual’s temperament and their need for self-
actualisation as well as job satisfaction rather than
the environment they are in (Maslow, 1943). Other
criticisms have been referenced by Olson (2004) as
well as the research outcome of the Hawthorne
Effect concluded that worker productivity was
temporarily higher because the workers were
motivated by the attention and being observed by the
research team. However, the intelligent agent in this
simulation that utilises the Hawthorne Effect theory
is trying to provide the best possible work
environment for its occupants and to satisfy their
requirements. The agent must also understand that
there could be a possibility of having a large gap
between the two occupants’ preferences which
might result in dramatic changes in their
environment and that should be avoided by
calculating an intermediate result that will benefit
both occupants. For example, if the preferences were
24°C and 26°C then the agent should use
intermediate values of 24.5°C and 25.5°C to reduce
the dramatic effects of having significantly different
temperatures. Although, this method may increase
energy usage as to compare with using the average
value of constant 25°C the intelligent agent’s
priority is for human comfort.
4.3 Simulation Design
The main focus of the simulation is how the agents
respond to the environment but to do this another
PERSONALISED AMBIENT INTELLIGENCE IN BUILDINGS VIA CONTEXT-AWARE AGENTS
21
part of the system should simulate the environment
itself. Figure 5 illustrates the environment and
external variables as required to help make the
simulation as realistic as possible.
Figure 5: Simulation Design.
The variables external to the scope are simulated
values to stimulate the intelligent agents. These will
be implemented as part of the system.
5 CRITICAL DISCUSSIONS
& FUTURE WORK
A simulation was developed to test the three
scenarios stated in Section 1. As this is an on-going
research project we can make initial evaluations
using test cases of the expected outcome.
5.1 User-Interface
The main objective of the user-interface is simplicity
in communicating with the agent which supports the
concept of “seamless integration” of intelligent
devices. The user-interface is designed as simple as
possible but transmits enough information to the
agent containing adequate intelligence for perception
and anticipation. The user-interface has been
designed to show the temperature and lighting
measurements to the occupants but this could cause
some implications because some users may know
what temperature settings they prefer and not relying
on the agent to perceive the occupants’ feelings for a
better judgement.
5.2 Training the Agent
The system allows the user to ‘train’ the agent and
make it understand the occupant’s preference. The
training uses a set of closed question, for example,
“Are you satisfied with the temperature/lighting?
Yes/No”. If the user selects “No” then it proceeds to
ask “What would you like to do with the
temperature/lighting? Increase/Decrease”. If the user
is satisfied then the system records the user’s
preferences. However, realistically the environment
is unable to adjust immediately within seconds and
therefore this training process could take a very long
time causing a placebo effect with the occupant
thinking that the environment has adjusted to their
preferences, temporarily. Another problem raised
here is the decision making logic of both
temperature and lighting is very simple. Probable
solution could be to use a binary algorithm to
produce better results for the learning agent.
5.3 Hawthorne Effect
In this simulation, the office environment is
segregated into zones. For example, Zone A has two
occupants with different temperature and lighting
preferences. Occupant A prefers the room
temperature to be at 23°C, 500LUX and Occupant B
would like the room temperature to be 25°C,
525LUX. The agent should fluctuate the temperature
and lighting between the two occupants preferences
at a very slow rate, i.e. cycle between these
preferences twice per hour. This method may
maximise user satisfaction but there are two
potential issues: changing the temperature is likely
to result in an increase in energy consumption and
altering the levels of light throughout the day may
cause more issues for occupants. But, as with other
methodologies (Chen, 1995; Meier, 1994; Buchanan,
1984) these resolves conflicts through compromise
but at least the solution here ensures that each
occupant is satisfied for various moments
throughout the day.
A fourth test case scenario was prepared but the
simulation did not support it. The fourth scenario
was to simulate how the agent interacts with the
environment when it senses that all the occupants
have entered the meeting room. From its historical
data the agent knows a meeting is scheduled ten
minutes prior to the meeting that was held regularly
on the same day and time. However, due to the
complexity and lack of development time this part of
the system was not fully implemented. It should
show how the agent tries to cater for all occupants
by calculating the average preference and fluctuating
from that measurement. It should also continue to
monitor who is actually present in the meeting room
and adapt the temperature and lighting to users’
preferences.
In conclusion, the results of this research project
could be criticised for a number of issues. In
hindsight, it could be argued that the use of a
qualitative research methodology would have been
useful in gaining a better understanding of the users
ICISO 2010 - International Conference on Informatics and Semiotics in Organisations
22
preferences in terms of the management of heating
and lighting. The project had assumed that the
Hawthorne Effect is preferable with little backing
from building occupants.
The heuristic training method could also be
criticised for its accuracy and its assessment of the
environment. For example, if two users are in the
same room and require a very similar temperature,
they may not be able to tell the difference between
the system’s behaviour in fluctuating between the
two selected heat settings. As a result, it would not
be possible to verify whether the Hawthorne Effect
theory is preferred by the occupants to an alternative
e.g. keeping the temperature to an average of the two
users’ preferences. External factors, such as the
user’s activity within the environment could also be
taken into account i.e. depending on a user’s level of
physical activity; the judgment of the environment’s
heat level could be misjudged and therefore have a
negative impact on the user’s perception of the
system and the heuristic training method.
There are several improvements or further
research that could be made, as listed below:
The user agent could benefit from a new
learning algorithm. Possibilities of using a
binary search algorithm to locate a particular
value when training the heating or lighting.
A dedicated agent that is solely responsible for
maintaining performance and efficiency of
energy usage.
Improving energy efficiency as this was not
included as one of the objectives in this paper.
The agents should take into account the internal
and external ambient environment and adjust
lighting and heating usage efficiently whilst
maintaining a comfortable environment. It is
expected that the proposed solution could
benefit greatly from this, for example, if the
outdoor air temperature is cooler than inside the
office then we can use natural ventilation to
dilute the outdoor cold air with the indoor warm
air. Going green and being sustainable is
currently a major topic. Research into agent
technology could be of great benefit to
implementing sustainable buildings for the
future.
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