Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hallway Monitoring: Distributed Data Processing with Wireless Sensor
  Networks   We present a sensor network testbed that monitors a hallway. It consists of
120 load sensors and 29 passive infrared sensors (PIRs), connected to 30
wireless sensor nodes. There are also 29 LEDs and speakers installed, operating
as actuators, and enabling a direct interaction between the testbed and
passers-by. Beyond that, the network is heterogeneous, consisting of three
different circuit boards---each with its specific responsibility. The design of
the load sensors is of extremely low cost compared to industrial solutions and
easily transferred to other settings. The network is used for in-network data
processing algorithms, offering possibilities to develop, for instance,
distributed target-tracking algorithms. Special features of our installation
are highly correlated sensor data and the availability of miscellaneous sensor
types.

5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th