Matching Items (5)
Filtering by

Clear all filters

152919-Thumbnail Image.png
Description
Monitoring of air pollutants is critical for many applications and studies. In

order to access air pollutants with high spatial and temporal resolutions, it is

necessary

Monitoring of air pollutants is critical for many applications and studies. In

order to access air pollutants with high spatial and temporal resolutions, it is

necessary to develop an affordable, small size and weight, low power, high

sensitivity and selectivity, and wireless enable device that can provide real time

monitoring of air pollutants. Three different kind of such devices are presented, they

are targeting environmental pollutants such as volatile organic components (VOCs),

nitrogen dioxide (NO2) and ozone. These devices employ innovative detection

methods, such as quartz crystal tuning fork coated with molecularly imprinted

polymer and chemical reaction induced color change colorimetric sensing. These

portable devices are validated using the gold standards in the laboratory, and their

functionality and capability are proved during the field tests, make them great tools

for various air quality monitoring applications.
ContributorsChen, Cheng, Ph.D (Author) / Tao, Nongjian (Thesis advisor) / Kiaei, Sayfe (Committee member) / Zhang, Yanchao (Committee member) / Tsow, Tsing (Committee member) / Arizona State University (Publisher)
Created2014
151055-Thumbnail Image.png
Description
Air pollution is one of the biggest challenges people face today. It is closely related to people's health condition. The agencies set up standards to regulate the air pollution. However, many of the pollutants under the regulation level may still result in adverse health effect. On the other hand, it

Air pollution is one of the biggest challenges people face today. It is closely related to people's health condition. The agencies set up standards to regulate the air pollution. However, many of the pollutants under the regulation level may still result in adverse health effect. On the other hand, it is not clear the exact mechanism of air pollutants and its health effect. So it is difficult for the health centers to advise people how to prevent the air pollutant related diseases. It is of vital importance for both the agencies and the health centers to have a better understanding of the air pollution. Based on these needs, it is crucial to establish mobile health sensors for personal exposure assessment. Here, two sensing principles are illustrated: the tuning fork platform and the colorimetric platform. Mobile devices based on these principles have been built. The detections of ozone, NOX, carbon monoxide and formaldehyde have been shown. An integrated device of nitrogen dioxide and carbon monoxide is introduced. Fan is used for sample delivery instead pump and valves to reduce the size, cost and power consumption. Finally, the future work is discussed.
ContributorsWang, Rui (Author) / Tao, Nongjian (Thesis advisor) / Forzani, Erica (Committee member) / Zhang, Yanchao (Committee member) / Karam, Lina (Committee member) / Arizona State University (Publisher)
Created2012
157188-Thumbnail Image.png
Description
The commercial semiconductor industry is gearing up for 5G communications in the 28GHz and higher band. In order to maintain the same relative receiver sensitivity, a larger number of antenna elements are required; the larger number of antenna elements is, in turn, driving semiconductor development. The purpose

The commercial semiconductor industry is gearing up for 5G communications in the 28GHz and higher band. In order to maintain the same relative receiver sensitivity, a larger number of antenna elements are required; the larger number of antenna elements is, in turn, driving semiconductor development. The purpose of this paper is to introduce a new method of dividing wireless communication protocols (such as the 802.11a/b/g
and cellular UMTS MAC protocols) across multiple unreliable communication links using a new link layer communication model in concert with a smart antenna aperture design referred to as Vector Antenna. A vector antenna is a ‘smart’ antenna system and as any smart antenna aperture, the design inherently requires unique microwave component performance as well as Digital Signal Processing (DSP) capabilities. This performance and these capabilities are further enhanced with a patented wireless protocol stack capability.
ContributorsJames, Frank Lee (Author) / Reisslein, Martin (Thesis advisor) / Seeling, Patrick (Thesis advisor) / McGarry, Michael (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2019
155620-Thumbnail Image.png
Description
Video capture, storage, and distribution in wireless video sensor networks

(WVSNs) critically depends on the resources of the nodes forming the sensor

networks. In the era of big data, Internet of Things (IoT), and distributed

demand and solutions, there is a need for multi-dimensional data to be part of

the

Video capture, storage, and distribution in wireless video sensor networks

(WVSNs) critically depends on the resources of the nodes forming the sensor

networks. In the era of big data, Internet of Things (IoT), and distributed

demand and solutions, there is a need for multi-dimensional data to be part of

the Sensor Network data that is easily accessible and consumable by humanity as

well as machinery. Images and video are expected to become as ubiquitous as is

the scalar data in traditional sensor networks. The inception of video-streaming

over the Internet, heralded a relentless research for effective ways of

distributing video in a scalable and cost effective way. There has been novel

implementation attempts across several network layers. Due to the inherent

complications of backward compatibility and need for standardization across

network layers, there has been a refocused attention to address most of the

video distribution over the application layer. As a result, a few video

streaming solutions over the Hypertext Transfer Protocol (HTTP) have been

proposed. Most notable are Apple’s HTTP Live Streaming (HLS) and the Motion

Picture Experts Groups Dynamic Adaptive Streaming over HTTP (MPEG-DASH). These

frameworks, do not address the typical and future WVSN use cases. A highly

flexible Wireless Video Sensor Network Platform and compatible DASH (WVSNP-DASH)

are introduced. The platform's goal is to usher video as a data element that

can be integrated into traditional and non-Internet networks. A low cost,

scalable node is built from the ground up to be fully compatible with the

Internet of Things Machine to Machine (M2M) concept, as well as the ability to

be easily re-targeted to new applications in a short time. Flexi-WVSNP design

includes a multi-radio node, a middle-ware for sensor operation and

communication, a cross platform client facing data retriever/player framework,

scalable security as well as a cohesive but decoupled hardware and software

design.
ContributorsSeema, Adolph (Author) / Reisslein, Martin (Thesis advisor) / Kitchen, Jennifer (Committee member) / Seeling, Patrick (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2017
161788-Thumbnail Image.png
Description
Collision-free path planning is also a major challenge in managing unmanned aerial vehicles (UAVs) fleets, especially in uncertain environments. The design of UAV routing policies using multi-agent reinforcement learning has been considered, and propose a Multi-resolution, Multi-agent, Mean-field reinforcement learning algorithm, named 3M-RL, for flight planning, where multiple vehicles need

Collision-free path planning is also a major challenge in managing unmanned aerial vehicles (UAVs) fleets, especially in uncertain environments. The design of UAV routing policies using multi-agent reinforcement learning has been considered, and propose a Multi-resolution, Multi-agent, Mean-field reinforcement learning algorithm, named 3M-RL, for flight planning, where multiple vehicles need to avoid collisions with each other while moving towards their destinations. In this system, each UAV makes decisions based on local observations, and does not communicate with other UAVs. The algorithm trains a routing policy using an Actor-Critic neural network with multi-resolution observations, including detailed local information and aggregated global information based on mean-field. The algorithm tackles the curse-of-dimensionality problem in multi-agent reinforcement learning and provides a scalable solution. The proposed algorithm is tested in different complex scenarios in both 2D and 3D space and the simulation results show that 3M-RL result in good routing policies. Also as a compliment, dynamic data communications between UAVs and a control center has also been studied, where the control center needs to monitor the safety state of each UAV in the system in real time, where the transition of risk level is simply considered as a Markov process. Given limited communication bandwidth, it is impossible for the control center to communicate with all UAVs at the same time. A dynamic learning problem with limited communication bandwidth is also discussed in this paper where the objective is to minimize the total information entropy in real-time risk level tracking. The simulations also demonstrate that the algorithm outperforms policies such as a Round & Robin policy.
ContributorsWang, Weichang (Author) / Ying, Lei (Thesis advisor) / Liu, Yongming (Thesis advisor) / Zhang, Junshan (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2021