4,533 research outputs found
Complex permittivity measurements at Ka-Band using rectangular dielectric waveguide
The rectangular dielectric waveguide (RDWG) technique
has been developed for the determination of the dielectric
constant of materials from effective refractive index measurements in the Q andWbands. This paper describes the use of an optimization method in conjunction with the RDWG technique for the determination of both the dielectric constant and loss tangent of materials at Ka-Band. The effect of the uncertainty in the measured
sample thickness is presented
Effects of Length and Diameter of Open-Ended Coaxial Sensor on its Reflection Coefficient
This paper presents a calibration technique for a coaxial sensor using a transmission signal approach. The sensor was fabricated from commercially available RG402/U and RG405/U semi-rigid coaxial cable. The length of the coaxial sensor was correlated with the attenuation and standing wave inside the coaxial line. The functions of multiple reflection amplitude and tolerance length with respect to the actual length of coaxial line were empirically formulated using regression analysis. The tolerances and the undesired standing wave which occurs along the coaxial line were analyzed in detai
M-ATTEMPT: A New Energy-Efficient Routing Protocol for Wireless Body Area Sensor Networks
In this paper, we propose a new routing protocol for heterogeneous Wireless
Body Area Sensor Networks (WBASNs); Mobility-supporting Adaptive
Threshold-based Thermal-aware Energy-efficientMulti-hop ProTocol (M-ATTEMPT). A
prototype is defined for employing heterogeneous sensors on human body. Direct
communication is used for real-time traffic (critical data) or on-demand data
while Multi-hop communication is used for normal data delivery. One of the
prime challenges in WBASNs is sensing of the heat generated by the implanted
sensor nodes. The proposed routing algorithm is thermal-aware which senses the
link Hot-spot and routes the data away from these links. Continuous mobility of
human body causes disconnection between previous established links. So,
mobility support and energy-management is introduced to overcome the problem.
Linear Programming (LP) model for maximum information extraction and minimum
energy consumption is presented in this study. MATLAB simulations of proposed
routing algorithm are performed for lifetime and successful packet delivery in
comparison with Multi-hop communication. The results show that the proposed
routing algorithm has less energy consumption and more reliable as compared to
Multi-hop communication.Comment: arXiv admin note: substantial text overlap with arXiv:1208.609
Empirical study of multi-label classification methods for image annotation and retrieval
This paper presents an empirical study of multi-label classification methods, and gives suggestions for multi-label classification that are effective for automatic image annotation applications. The study shows that triple random ensemble multi-label classification algorithm (TREMLC) outperforms among its counterparts, especially on scene image dataset. Multi-label k-nearest neighbor (ML-kNN) and binary relevance (BR) learning algorithms perform well on Corel image dataset. Based on the overall evaluation results, examples are given to show label prediction performance for the algorithms using selected image examples. This provides an indication of the suitability of different multi-label classification methods for automatic image annotation under different problem settings.<br /
Multilabel classification by BCH code and random forests
This paper uses error correcting codes for multilabel classification. BCH code and random forests learner are used to form the proposed method. Thus, the advantage of the error-correcting properties of BCH is merged with the good performance of the random forests learner to enhance the multilabel classification results. Three experiments are conducted on three common benchmark datasets. The results are compared against those of several exiting approaches. The proposed method does well against its counterparts for the three datasets of varying characteristics.<br /
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