DESIGN OF EFFICIENT IN-NETWORK DATA PROCESSING AND DISSEMINATION FOR VANETS

By providing vehicle-to-vehicle and vehicle-to-infrastructure wireless communications, vehicular ad hoc networks (VANETs), also known as the “networks on wheels”, can greatly enhance traffic safety, traffic efficiency and driving experience for intelligent transportation system (ITS). However, the unique features of VANETs, such as high mobility and uneven distribution of vehicular nodes, impose critical challenges of high efficiency and reliability for the implementation of VANETs. This dissertation is motivated by the great application potentials of VANETs in the design of efficient in-network data processing and dissemination. Considering the significance of message aggregation, data dissemination and data collection, this dissertation research targets at enhancing the traffic safety and traffic efficiency, as well as developing novel commercial applications, based on VANETs, following four aspects: 1) accurate and efficient message aggregation to detect on-road safety relevant events, 2) reliable data dissemination to reliably notify remote vehicles, 3) efficient and reliable spatial data collection from vehicular sensors, and 4) novel promising applications to exploit the commercial potentials of VANETs. Specifically, to enable cooperative detection of safety relevant events on the roads, the structure-less message aggregation (SLMA) scheme is proposed to improve communication efficiency and message accuracy. The scheme of relative position based message dissemination (RPB-MD) is proposed to reliably and efficiently disseminate messages to all intended vehicles in the zone-of-relevance in varying traffic density. Due to numerous vehicular sensor data available based on VANETs, the scheme of compressive sampling based data collection (CS-DC) is proposed to efficiently collect the spatial relevance data in a large scale, especially in the dense traffic. In addition, with novel and efficient solutions proposed for the application specific issues of data dissemination and data collection, several appealing value-added applications for VANETs are developed to exploit the commercial potentials of VANETs, namely general purpose automatic survey (GPAS), VANET-based ambient ad dissemination (VAAD) and VANET based vehicle performance monitoring and analysis (VehicleView). Thus, by improving the efficiency and reliability in in-network data processing and dissemination, including message aggregation, data dissemination and data collection, together with the development of novel promising applications, this dissertation will help push VANETs further to the stage of massive deployment

Dopamine Surface Modification of Trititanate Nanotubes: Proposed In‐Situ Structure Models

Two models for self‐assembled dopamine on the surface of trititanate nanotubes are proposed: individual monomer units linked by π–π stacking of the aromatic regions and mono‐attached units interacting through hydrogen bonds. This was investigated with solid state NMR spectroscopy studies and powder X‐ray diffraction.Double bind: Two models for self‐assembled dopamine on the surface of trititanate nanotubes are proposed: individual trimer units linked by π–π stacking of the aromatic regions and mono‐attached units interacting through hydrogen bonds. This was investigated by solid state NMR spectroscopy studies and powder X‐ray diffraction.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137420/1/chem201600075.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137420/2/chem201600075_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137420/3/chem201600075-sup-0001-misc_information.pd

Establishment and characterization of three new human breast cancer cell lines derived from Chinese breast cancer tissues

<p>Abstract</p> <p>Background</p> <p>Breast cancer is a major malignancy affecting females worldwide. It is the most common cause of death from cancer in women. Cell lines are widely used in laboratory research and particularly as <it>in vitro </it>models in cancer research. But we found that the routinely used breast cancer cell lines were mostly derived from Caucasians or African-Americans. There were few standard models to study the pathogenic mechanism at molecular level and cell signaling pathway of breast cancer for Asian patients. It is quite necessary to establish new breast cancer cell lines from xanthoderm to study the pathogenic mechanism and therapeutic methods.</p> <p>Results</p> <p>Three new breast cancer cell lines, designated BC-019, BC-020 and BC-021, were successfully established and characterized from breast invasive ductal carcinoma tissues of three Chinese female patients. These new cell lines growing as adherent monolayer with characteristic epithelial morphology could be maintained continuously <it>in vitro</it>, and they were ER-, PR- and C-erbB-2-positive. Their chromosomes showed high hyperdiploidy and complex rearrangements, and they displayed aggressive tumorigencity in tumorigenesis test.</p> <p>Conclusion</p> <p>The three newly established breast cancer cell lines from Chinese patients were tested for a number of, and the results indicate that the cell lines were in good quality and could be served as new cell models in breast cancer study.</p

Graphene as a Promising Electrode for Low-Current Attenuation in Nonsymmetric Molecular Junctions

International audienceWe have measured the single-molecule conductance of 1,$\it n$-alkanedithiol molecular bridges ($\it n$ = 4, 6, 8, 10, 12) on a graphene substrate using scanning tunneling microscopy (STM)-formed electrical junctions. The conductance values of this homologous series ranged from 2.3 nS ($\it n$= 12) to 53 nS ($\it n$= 4), with a decay constant β$_n$ of 0.40 per methylene (−CH$_2$) group. This result is explained by a combination of density functional theory (DFT) and Keldysh− Green function calculations. The obtained decay, which is much lower than the one obtained for symmetric gold junctions, is related to the weak coupling at the molecule−graphene interface and the electronic structure of graphene. As a consequence, we show that using graphene nonsymmetric junctions and appropriate anchoring groups may lead to a much-lower decay constant and more-conductive molecular junctions at longer lengths

Hand Motion Classification Using a Multi-Channel Surface Electromyography Sensor

The human hand has multiple degrees of freedom (DOF) for achieving high-dexterity motions. Identifying and replicating human hand motions are necessary to perform precise and delicate operations in many applications, such as haptic applications. Surface electromyography (sEMG) sensors are a low-cost method for identifying hand motions, in addition to the conventional methods that use data gloves and vision detection. The identification of multiple hand motions is challenging because the error rate typically increases significantly with the addition of more hand motions. Thus, the current study proposes two new methods for feature extraction to solve the problem above. The first method is the extraction of the energy ratio features in the time-domain, which are robust and invariant to motion forces and speeds for the same gesture. The second method is the extraction of the concordance correlation features that describe the relationship between every two channels of the multi-channel sEMG sensor system. The concordance correlation features of a multi-channel sEMG sensor system were shown to provide a vast amount of useful information for identification. Furthermore, a new cascaded-structure classifier is also proposed, in which 11 types of hand gestures can be identified accurately using the newly defined features. Experimental results show that the success rate for the identification of the 11 gestures is significantly high

RPB-MD: Providing robust message dissemination for vehicular ad hoc networks

To improve traffic safety and efficiency, it is vital to reliably send traffic-related messages to vehicles in the targeted region in vehicular ad hoc networks (VANETs). In this paper, we propose a novel scheme, relative position based message dissemination (RPB-MD), to reliably and efficiently disseminate messages to the vehicles in the zone-of-relevance. Firstly, the relative position based (RPB) addressing model is proposed to effectively define the intended receivers in the zone-of-relevance. To ensure high message delivery ratio and low delivery delay, directional greedy broadcast routing (DGBR) is introduced to make a group of candidate nodes hold the message for high reliability. Moreover, to guarantee efficiency, the protocol time parameters are designed adaptively according to the message attributes and local vehicular traffic density. The protocol feasibility is analyzed to illustrate the robustness and reliability of RPB-MD. Simulation results show that RPB-MD, compared with representative existing schemes, achieves high delivery ratio, limited overhead, reasonable delay and high network reachability under different vehicular traffic density and data sending rate. © 2011 Elsevier B.V. All rights reserved

RPB-MD: A novel robust message dissemination method for VANETs

Robust multi-hop message dissemination in Vehicular Ad hoc Networks (VANETs) is challenging due to the high mobility and frequent partitioning. In this paper, we propose a novel scheme referred as the relative position based message dissemination (RPB-MD), to robustly disseminate messages in VANETs. The relative position based (RPB) addressing model is proposed to define the intended receivers without requiring exterior location service. To achieve robust message dissemination with vehicular traffic independency, RPB- MD adopts the directional greedy broadcast routing approach to forward messages based on position and direction information. The performance of the proposed scheme is evaluated through simulations. Simulation results show that RPB-MD achieves high delivery ratio, limited overhead and reasonable delay. © 2008 IEEE

Structure-less Message Aggregation (SLMA): Reliably and efficiently improve information precision and certainty for VANETs

In VANETs, message aggregation is crucial to reduce information redundancy and communication overhead. In addition, it can effectively decrease the information inaccuracy from the on-board sensors. In this paper, we propose a novel scheme, event driven structure-less message aggregation (SLMA), for safety-relevant VANET applications. The key motive of SLMA is to reliably and efficiently improve information accuracy and reduce communication overhead with limited delay at the same time. To our best knowledge, this is the first paper to address these goals of message aggregation simultaneously in VANETs. Using multiple level parallel fusion model to provide high reliability, the structure-less aggregation framework eliminates packet exchanges for aggregation structure formation and maintenance. Bayesian fusion algorithm is adopted to effectively achieve precise event detection on the road. Simulation results show that SLMA scheme efficiently reduces the communication overhead with reasonable delay. Meanwhile, it can greatly improve information accuracy. ©2010 IEEE