API TR 2569:2008-Evaporative Loss from Closed-vent Internal Floating-roof Storage Tanks TECHNICAL REPORT

اختصاصی از فی دوو API TR 2569:2008-Evaporative Loss from Closed-vent Internal Floating-roof Storage Tanks TECHNICAL REPORT دانلود با لینک مستقیم و پر سرعت .

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API Technical Report 2569:2008

Evaporative Loss from Closed-vent Internal Floating-roof Storage Tanks TECHNICAL REPORT

دانلود مقاله Multiple Receiver Strategies for Minimizing Packet Loss in Dense Sensor Networks

اختصاصی از فی دوو دانلود مقاله Multiple Receiver Strategies for Minimizing Packet Loss in Dense Sensor Networks دانلود با لینک مستقیم و پر سرعت .

Bernhard Firner, Chenren Xu, Richard Howard, and Yanyong Zhang

ABSTRACT
A typical wireless sensor network consists of many small sensors
that collect instrument data around their locations and
forward it to a central location for data processing. These
networks can be deployed to monitor livestock and agricultural
assets, products in a store, patients in a hospital, and
so on. In many cases sensors have to be densely deployed,
and collisions or overhead due to collision avoidance will
considerably degrade the system performance below an application’s
required levels. With the decreasing cost of radio
devices the obvious solution to this problem is the use
of multiple receivers on different radio channels. However,
we show that if receivers can be placed in different locations
then increasing the number of receivers on a single
channel will increase the rate of the capture effect and decrease
collision losses, while also increasing the fairness of
the transmitters’ radio links. Not only can this single channel
approach be more effective than using multiple channels,
it is also required for some techniques, such as localization,
where each receiver must be able to detect a transmission
from any transmitter. We also show that the optimal choice
between these two solutions is influenced by the radio attenuation
rate and the number of receivers in the system.
Categories and Subject Descriptors: C.2.1 [Computer-
Communication Networks]:
Network Architecture and Design—Wireless communication
General Terms: Experimentation, Measurement, Performance

Keywords: Scalability, Capture Effect