Page 63 - Fister jr., Iztok, and Andrej Brodnik (eds.). StuCoSReC. Proceedings of the 2015 2nd Student Computer Science Research Conference. Koper: University of Primorska Press, 2015
P. 63
and security mode. When these modes are in effect the
system minimizes power consumption of periphery devices,
locks doors, closes window blinds and adjust the timetable
of autonomous task such as vacuuming.
5. USER IDENTIFICATION AND LOCATION
MODULE
The purpose of this module is locating and identifying the
user in a collection of intelligent objects i.e rooms in a smart
house. In smart identifying and locating users can be chal-
lenging. Due to the signal attenuation caused by construc-
tion materials, the satellite base Global Positioning System
(GPS) loses significant power indoors affecting the required
coverage for receivers by at lest four satellites. We imple-
mented a smart phone application that will monitor move-
ment indoors. Nowadays almost every person has a smart
phone, which makes smart phones a good target platform.
The application is developed for Android operating system.
The application runs as a daemon, detecting Wi-Fi signals
and their strength. The application is able to detect differ-
ences between obtained signal strengths in attempt to de-
termine the position of the smart phone using triangulation.
In urban areas the application works as expected, whereas
inaccuracy is expected in areas with poor access point cov-
erage.
The identification is done with the help of a login screen as
can be seen in Figure 2.
User logs into the application that triangulates the smart Figure 2
phone position and determines in which room the user cur-
rently is. Considering the battery consumption, measure- values the function has lesser value then the search value.
ments are done only when moving. When the application This point will consequently be the best possible state for all
detects the change in the room location it sends the infor- the users because any other value, would have been worse
mation to the server trough a REST interface. This module for at least one of the users. It is important to note that
allows us to track the user inside the building. Identifying the continues function where the limit to infinity equals 0
and locating users inside an intelligent object is key. Based is bounded in the set of real numbers. This means that the
upon the user data and his or her location the system can function has a maximum value.
control periphery units accordingly.
We describe the steps of the algorithm in more detail below:
6. METHODOLOGY
1. We pick a large enough value so that it is bigger then
One of the main goals of this project is to design an adap- all the maxima of all the functions. Because all the
tive algorithm that will adjust the parameters of external functions are positive we pick a minimum value of 0.
units, such as room temperature, room brightness etc. The
algorithm will adapt the output parameters with respect to 2. With the two picked values we perform bisection as
users wishes and changes the user has made in the past. follows: We take the middle of the two values and for
An important feature and challenge of the algorithm was every function we find such intervals in which the func-
the ability to adjust the output parameters in cases where tion is greater than the given value. We then find the
multiple users have different requirements. In such cases intersection of all the intervals. If the intersection is
we cannot expect the algorithm to fulfill requirements of all empty, the new middle value becomes the new maxi-
users, instead the algorithm finds the best parameter values mum value. We repeat step 2.
that will hopefully suit all users to some extent.
We use controlling temperature as an example and assume 3. The algorithm stops when the intersection of all in-
it’s change to be continuous. At the initialization we assume
the desired temperature of the user is known. The temper-
ature function will be normalized so that the integral from
minus infinity to infinity equals 1 and the limits to infinity
and minus infinity equal 0. Suppose we now have multiple
users with each of them having its own desired temperature.
Consequently we now have multiple such functions, and our
goal is to predict a temperature, such that in all the other
StuCoSReC Proceedings of the 2015 2nd Student Computer Science Research Conference 63
Ljubljana, Slovenia, 6 October
system minimizes power consumption of periphery devices,
locks doors, closes window blinds and adjust the timetable
of autonomous task such as vacuuming.
5. USER IDENTIFICATION AND LOCATION
MODULE
The purpose of this module is locating and identifying the
user in a collection of intelligent objects i.e rooms in a smart
house. In smart identifying and locating users can be chal-
lenging. Due to the signal attenuation caused by construc-
tion materials, the satellite base Global Positioning System
(GPS) loses significant power indoors affecting the required
coverage for receivers by at lest four satellites. We imple-
mented a smart phone application that will monitor move-
ment indoors. Nowadays almost every person has a smart
phone, which makes smart phones a good target platform.
The application is developed for Android operating system.
The application runs as a daemon, detecting Wi-Fi signals
and their strength. The application is able to detect differ-
ences between obtained signal strengths in attempt to de-
termine the position of the smart phone using triangulation.
In urban areas the application works as expected, whereas
inaccuracy is expected in areas with poor access point cov-
erage.
The identification is done with the help of a login screen as
can be seen in Figure 2.
User logs into the application that triangulates the smart Figure 2
phone position and determines in which room the user cur-
rently is. Considering the battery consumption, measure- values the function has lesser value then the search value.
ments are done only when moving. When the application This point will consequently be the best possible state for all
detects the change in the room location it sends the infor- the users because any other value, would have been worse
mation to the server trough a REST interface. This module for at least one of the users. It is important to note that
allows us to track the user inside the building. Identifying the continues function where the limit to infinity equals 0
and locating users inside an intelligent object is key. Based is bounded in the set of real numbers. This means that the
upon the user data and his or her location the system can function has a maximum value.
control periphery units accordingly.
We describe the steps of the algorithm in more detail below:
6. METHODOLOGY
1. We pick a large enough value so that it is bigger then
One of the main goals of this project is to design an adap- all the maxima of all the functions. Because all the
tive algorithm that will adjust the parameters of external functions are positive we pick a minimum value of 0.
units, such as room temperature, room brightness etc. The
algorithm will adapt the output parameters with respect to 2. With the two picked values we perform bisection as
users wishes and changes the user has made in the past. follows: We take the middle of the two values and for
An important feature and challenge of the algorithm was every function we find such intervals in which the func-
the ability to adjust the output parameters in cases where tion is greater than the given value. We then find the
multiple users have different requirements. In such cases intersection of all the intervals. If the intersection is
we cannot expect the algorithm to fulfill requirements of all empty, the new middle value becomes the new maxi-
users, instead the algorithm finds the best parameter values mum value. We repeat step 2.
that will hopefully suit all users to some extent.
We use controlling temperature as an example and assume 3. The algorithm stops when the intersection of all in-
it’s change to be continuous. At the initialization we assume
the desired temperature of the user is known. The temper-
ature function will be normalized so that the integral from
minus infinity to infinity equals 1 and the limits to infinity
and minus infinity equal 0. Suppose we now have multiple
users with each of them having its own desired temperature.
Consequently we now have multiple such functions, and our
goal is to predict a temperature, such that in all the other
StuCoSReC Proceedings of the 2015 2nd Student Computer Science Research Conference 63
Ljubljana, Slovenia, 6 October
