| 1. |
- Boario, Carlo Alberto, et al.
(author)
-
TempLab : A testbed infrastructure to study the impact of temperature on wireless sensor networks
- 2014
-
In: IPSN 2014 - Proceedings of the 13th International Symposium on Information Processing in Sensor Networks (Part of CPS Week). - : IEEE Computer Society. - 9781479931460 ; , s. 95-106
-
Conference paper (peer-reviewed)abstract
- Temperature has a strong impact on the operations of all electrical and electronic components. In wireless sensor nodes, temperature variations can lead to loss of synchronization, degradation of the link quality, or early battery depletion, and can therefore affect key network metrics such as throughput, delay, and lifetime. Considering that most outdoor deployments are exposed to strong temperature variations across time and space, a deep understanding of how temperature affects network protocols is fundamental to comprehend flaws in their design and to improve their performance. Existing testbed infrastructures, however, do not allow to systematically study the impact of temperature on wireless sensor networks. In this paper we present TempLab, an extension for wireless sensor network testbeds that allows to control the on-board temperature of sensor nodes and to study the effects of temperature variations on the network performance in a precise and repeatable fashion. TempLab can accurately reproduce traces recorded in outdoor environments with fine granularity, while minimizing the hardware costs and configuration overhead. We use TempLab to analyse the detrimental effects of temperature variations (i) on processing performance, (ii) on a tree routing protocol, and (iii) on CSMA-based MAC protocols, deriving insights that would have not been revealed using existing testbed installations.
|
|
| 2. |
- Hermans, Frederik, et al.
(author)
-
Poster Abstract:Supporting Heterogeneous LCD/Camera Links
- 2014. - 10
-
In: Proc. 13th International Symposium on Information Processing in Sensor Networks. - Piscataway, NJ : IEEE Press. - 9781479931460 ; , s. 289-290
-
Conference paper (peer-reviewed)abstract
- Visible light communication over LCD/camera links offers a potential complement to traditional RF communication technology such as WiFi or cellular networks. However, the heterogeneity in receivers (e.g., mobile phone cameras) presents a challenge because the receivers differ widely in resolution, distance to the transmitter (LCD), and other factors, and therefore they differ in channel quality. We are researching a communication scheme in which each receiver can decode as much data from an LCD's transmission as the receiver's channel supports. The core idea is to encode the payload into an image's frequency representation rather than directly into pixels. We have successfully transmitted data using a prototype implementation and are currently investigating appropriate channel models.
|
|
| 3. |
- Niroumand, Kamyar, et al.
(author)
-
Poster abstract : SADSense: Personalized mobile sensing for seasonal effects on health
- 2014
-
In: IPSN 2014 - Proceedings of the 13th International Symposium on Information Processing in Sensor Networks (Part of CPS Week). - Piscataway, NJ : IEEE Computer Society. - 9781479931460 ; , s. 295-296
-
Conference paper (other academic/artistic)abstract
- People's moods and activities are heavily affected by their environment, which changes significantly throughout the year. The variable of daylight hours is huge for countries in extreme latitudes, impacting the population's health and well-being. In this paper, we present a smartphone application that efficiently and accurately measures a person's light exposure, mood and activity levels. We performed a preliminary study to show effective data collection using on-board sensors in the mobile phones. © 2014 IEEE.
|
|
| 4. |
- Varshney, Ambuj, et al.
(author)
-
Directional Transmissions and Receptions for Burst Forwarding using Disjoint Paths
- 2014
-
In: Proc. 13th International Symposium on Information Processing in Sensor Networks. - Piscataway, NJ : IEEE Press. - 9781479931460 ; , s. 307-308
-
Conference paper (peer-reviewed)abstract
- Bulk data transmission is an important traffic pattern of many sensor network applications. These applications deliver large amounts of sensed data to a sink node for further processing. Most of the existing bulk data transmission protocols use a single flow of communication. This is inefficient as the radio at the source node is transmitting and the sink node is receiving packets for only half of the duration of the burst. We show in this paper that reduced contention because of directional communication enables us to construct node disjoint paths from the source to the sink node using only one wireless channel. This allows us to forward subsequent packets in the burst on the disjoint paths which maximises the radio transmit and receive time at the source and the sink node respectively. We demonstrate that this doubles the sink throughput as compared to a single flow of communication.
|
|
| 5. |
- Voigt, Thiemo, et al.
(author)
-
Smartphone Support for Persons Who Stutter
- 2014
-
In: Proc. 13th International Symposium on Information Processing in Sensor Networks. - Piscataway, NJ : IEEE Press. - 9781479931460 ; , s. 293-294
-
Conference paper (peer-reviewed)abstract
- Stuttering is a very complex speech disorder that affects around 0.7% of adults while around 5% of the population have stuttered at some point. A large percentage of the affected people tend to speak more fluently when their own speech is played back to their ear with some type of alteration. While this has been done with special devices, smartphones can be used for this purpose. We report on our initial experiences on building such an application and demonstrate problems with delay caused by the lack of real-time support for audio playback in the Android operating system. We also discuss ideas for future work to improve app support for people who stutter.
|
|
