Changeset 2818

Show
Ignore:
Timestamp:
10/30/09 20:28:36 (4 weeks ago)
Author:
jaein
Message:
 
Location:
HydroWatch/Tim/doc/ipsn10
Files:
2 modified

Legend:

Unmodified
Added
Removed
  • HydroWatch/Tim/doc/ipsn10/energy.bib

    r2814 r2818  
    1010 
    1111 
    12 @conference{hui08, 
     12@conference{hui08sensys, 
    1313        Author = {Jonathan Hui and David Culler}, 
    1414        Booktitle = {ACM Sensys}, 
     
    9999        Author = {Bugra Gedik and Ling Liu and Philip S. Yu}, 
    100100        Issn = {1045-9219}, 
    101         Journal = {IEEE Transactions on Parallel and Distributed Systems}, 
     101        Journal = {IEEE TPDS}, 
    102102        Number = {12}, 
    103103        Pages = {1766-1783}, 
     
    202202        Year = {2007}} 
    203203 
    204 @article{hui08sensys, 
    205         Address = {New York, NY, USA}, 
    206         Author = {Hui,, Jonathan W. and Culler,, David E.}, 
    207         Doi = {http://doi.acm.org/10.1145/1460412.1460415}, 
    208         Isbn = {978-1-59593-990-6}, 
    209         Journal = {SenSys '08: Proceedings of the 6th ACM article on Embedded network sensor systems}, 
    210         Location = {Raleigh, NC, USA}, 
    211         Pages = {15--28}, 
    212         Publisher = {ACM}, 
    213         Title = {IP is dead, long live IP for wireless sensor networks}, 
    214         Year = {2008}} 
    215  
    216204@article{ye06sensys, 
    217205        Author = {Wei Ye and Fabio Silva and John Heidemann}, 
     
    313301@article{simjee06, 
    314302        Author = {Farhan Simjee and Pai H. Chou}, 
    315         Journal = {International Symposium on Low Power Electronics and Design (ISLPED `06)}, 
     303        Journal = {ISLPED}, 
    316304        Month = {Oct}, 
    317305        Title = {Everlast: Long-Life, Supercapacitor-Operated Wireless Sensor Node}, 
     
    507495@article{kansal03, 
    508496        Author = {Kansal,, Aman and Srivastava,, Mani B.}, 
    509         Journal = {ISLPED `03}, 
     497        Journal = {ISLPED}, 
    510498        Title = {An environmental energy harvesting framework for sensor networks}, 
    511499        Year = 2003} 
  • HydroWatch/Tim/doc/ipsn10/sec_eval.tex

    r2817 r2818  
    1111In order to validate the performance of our optimization protocol, we have retrospectively tested our protocol for several months on outdoor environmental solar data. Given the lack of periods of little sun from this data, we simulated this by inserting periods of low solar energy in order to be able to validate performance under these types of conditions. 
    1212 
    13 Figure~\ref{fig:vlsb1} shows the performance of the protocol over 110 days of data for a typical node. In this case, an interval is defined as one day where the parameters $F_s(n,k)$ and $F_r(n,k)$ are recalculated every day/interval. Figure~\ref{fig:vlsb1}(a) shows the case where 3 days ahead energy prediction is used, whereas Figure~\ref{fig:vlsb1}(b) shows the case where an estimate of the energy on the day only is used. We can observe the way in which longer-term energy forecast information changes the behavior of the system. The forecast information allows the system to take greater risks in how far it can drop it's stored energy below the target value. This in turn allows for a smoother progression of report and sample parameters. In the case of limited forecast information, there is much greater fluctuation in these same parameters in order to keep within the target energy range. 
     13Figure~\ref{fig:vlsb1} shows the performance of the protocol over 110 days of data for a typical node. In this case, an interval is defined as one day where the parameters $F_s(n,k)$ and $F_r(n,k)$ are recalculated every day/interval. Figure~\ref{fig:vlsb1}(a) shows the case where 3 days ahead energy prediction is used, whereas Figure~\ref{fig:vlsb1}(b) shows the case where an estimate of the energy on the day only is used. We can observe the way in which longer-term energy forecast information changes the behavior of the system. The forecast information allows the system to take greater risks in how far it can drop it's stored energy below the target value. This in turn allows for a smoother progression of report and sample parameters. In the case of limited forecast information, there is much greater fluctuation in the same parameters in order to keep within the target energy range. 
    1414 
    1515\begin{figure*}[ht] 
     
    2525 
    2626 
    27 This smoothing effect brought about by greater prediction power can also be observed in the distribution of utility values as defined in Equation~\ref{equ:utility}. Figure~\ref{fig:util_cdf1} shows the CDFs of utility of both cases where greater prediction can be seen to reduce the proportion of days with low utility. This effect can further be observed in Figure~\ref{fig:UvsEh1} showing the relationship between daily energy harvested and utility. Additional predictive power enables the system to greatly increase utility during days with little harvested energy, which is achieved by a slight reduction in utility in days with high energy. 
     27This smoothing effect brought about by greater prediction power can also be observed in the distribution of utility values as defined in Equation~\ref{equ:utility}. Figure~\ref{fig:util_cdf1} shows the CDFs of utility of both cases where greater prediction can be seen to reduce the proportion of days with low utility. This effect can further be observed in Figure~\ref{fig:UvsEh1} showing the relationship between daily energy harvested and utility. Additional predictive power enables the system to greatly increase utility during days with little harvested energy, which is achieved by a slight reduction in utility on days with high energy. 
    2828 
    2929%\begin{figure}[ht] 
     
    9191\subsection{Comparison with Related Work} 
    9292For comparative analysis of our proposed protocol, we consider two related works: 
    93 Vigorito \cite{vigorito07} and Hsu \cite{hsu06} as described in Section~\ref{sec:relatedadapt}. The key differences between our protocol and those of the related work are also described in this section. 
     93Vigorito \cite{vigorito07} and Hsu \cite{hsu06} as described in Section~\ref{sec:relatedadapt}. The key differences between our protocol and the related work are also described in this section. 
    9494 
    9595%Figure~\ref{fig:vigorito_algorithm} shows