International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The US Army Aberdeen Test Center (ATC) is acquiring, transferring, and databasing data during all phases of automotive testing using networked data acquisition devices. The devices are small ruggedized computer-based systems programmed with specific data acquisition tasks and then networked together with other devices in order to share information within a test item or vehicle. One of the devices is also networked to a ground-station for monitor, control and data transfer of any of the devices on the net. Application of these devices has varied from single vehicle tests in a single geographical location up to a 100-vehicle nationwide test. Each device has a primary task such as acquiring data from vehicular data busses (MIL-STD-1553, SAE J1708 bus, SAE J1939 bus, RS-422 serial bus, etc.), GPS (time and position), analog sensors and video with audio. Each device has programmable options, maintained in a configuration file, that define the specific recording methods, real-time algorithms to be performed, data rates, and triggering parameters. The programmability of the system and bi-directional communications allow the configuration file to be modified remotely after the system is fielded. The primary data storage media of each device is onboard solid-state flash disk; therefore, a continuous communication link is not critical to data gathering. Data are gathered, quality checked and loaded into a database for analysis. The configuration file, as an integral part of the database, ensures configuration identity and management. A web based graphical user interface provides preprogrammed query options for viewing, summarizing, graphing, and consolidating data. The database can also be queried for more detailed analyses. The architecture for this network approach to field data acquisition was under the Aberdeen Test Center program Versatile Information System Integrated On-Line (VISION). This paper will describe how the merging of data acquisition systems to network communications and information management tools provides a powerful resource for system engineers, analysts, evaluators and acquisition personnel.

The nature of learning and teaching in higher education has changed significantly in recent years. The emergence of social media and technologies has had a profound impact upon learner engagement and tutors have had to adapt their learning and teaching strategies accordingly. The thesis discusses the author’s published body of research and presents a pedagogical framework for engaging the networked learner. The framework is based upon three perspectives that have emerged from the author’s research. Firstly, different learning paradigms should be acknowledged when developing pedagogical approaches to using learning technologies. Secondly, the thesis discusses how the author’s research on learning technologies, including VLEs and iPod technologies, should embrace networked communities and learner empowerment. Thirdly, the research on learning approaches is discussed which acknowledges different learning behaviours and the adoption of differentiated methods in learning and teaching. Whilst discussing the evolving nature of the learning environment, the pedagogical framework draws together each of the aforementioned perspectives. The framework raises a number of factors for engaging the networked learner. A set of practical guidelines based around institutional, tutor and learner perspectives are discussed and underpin the application of the framework. The thesis concludes with theoretical observations on learning and learning theory and presents limitations and areas for further research.

Research Doctorate - Doctor of Philosophy (PhD) / This thesis studies control systems with communication constraints. Such constraints arise due to the fact that practical control systems often use non-transparent communication links, i.e., links subject to data-rate constraints, random data-dropouts or random delays. Traditional control theory cannot deal with such constraints and the need for new tools and insights arises. We study two problems: control with average data-rate constraints and control over analog erasure channels with i.i.d. dropout profiles. When focusing on average data-rate constraints, it is natural to ask whether information theoretic ideas may assist the study of networked control systems. In this thesis we show that it is possible to use fundamental information theoretic concepts to arrive at a framework that allows one to tackle performance related control problems. In doing so, we show that there exists an exact link between control systems subject to average data-rate limits, and control systems which are closed over additive i.i.d. noise channels subject to a signal-to-noise ratio constraint. On the other hand, in the case of control systems subject to i.i.d. data-dropouts, we show that there exists a second-order moments equivalence between a linear feedback system which is interconnected over an analog erasure channel, and the same system when it is interconnected over an additive i.i.d. noise channel subject to a signal-to-noise ratio constraint. From the results foreshadowed above, it follows that the study of control systems closed over signal-to-noise ratio constrained additive i.i.d. noise channels is a task of relevance to many networked control problems. Moreover, the interplay between signal-to-noise ratio constraints and control objectives is an interesting issue in its own right. This thesis starts with such a study. Then, we use the resultant insights to address performance issues in control systems subject to either average data-rate constraints or i.i.d. data-dropouts. Our approach shows that, once key equivalences are exposed, standard control intuition and synthesis machinery can be used to tackle networked control problems in an exact manner. It also sheds light into fundamental results in the literature and gives (partial) answers to several previously open questions. We believe that the insights in this thesis are of fundamental importance and, to the best of the author's knowledge, novel.

Social media on the internet allows both public and private actors to communicate with each other. The aim of this qualitative study is to explore the relationship between the public and the private in social media on the internet, specifically with emphasis on the identities which are shaped in this relationship. The social media explored in this study is the micro blog Twitter. Data was collected from the pages of three public and private actors on Twitter, specifically with concern to their interaction with public and/or private actors. The data was analysed with support in sociological theories on modernity, identity, self-identity, socialisation and Erving Goffman's theories on everyday expression. The results show that expressions of public identities from public actors are interwoven with expressions of private identities in the interaction with private actors. One of the study's main findings is the individualisation of public actors on Twitter in the interaction with private actors. Sometimes, the authority is shifted from the public actors to the private actors, which support the theory of the individualisation of public actors on the micro blog Twitter.

The importance of real-time communication at the device level in a factory automation setup is a widely researched area. This research is an effort to experimentally verify if Ethernet can be used as a real-time communication standard in a factory automation setup, by observing the effects of packet delays, packet loss, and network congestion on the performance of a networked control system (NCS). The NCS experimental setup used in this research involves real-time feedback control of multiple plants like DC motors and a magnetic-levitation system connected to one or more controllers. A multi-client-multi-server architecture on a local area network (LAN) was developed using user datagram protocol (UDP) as the communication protocol. Key observations are as follows. (1) The multi-client-single-server system showed the highest packet delays compared to single-client-single-server architecture. (2) In the singleclient- single-server system, as the Ethernet link utilization increased beyond 82 percent, the average packet delays and steady-state error of the DC motor speed-control system increased by 2231 percent and 304 percent, respectively. (3) Even under high link utilization, adding an additional server to the NCS reduced average packet delays considerably. (4) With large packet sizes, higher packet rates were automatically throttled by Ethernet’s flow control mechanism affecting the real-time communication negatively. (5) In the multiclient- multi-server architecture, average packet delays at higher packet rates, and at higher packet lengths were found to be 40 percent lesser than the those of the single-clientsingle- server system and 87.5 percent lesser than those of the multi-client-single-server system.

The development of telerobotic systems has evolved from Single Operator Single Robot (SOSR) systems to Multiple Operator Multiple Robot (MOMR) systems. The relationship between human operators and robots follows the master-slave control architecture and the requests for controlling robot actuation are completely generated by human operators. Recently, the fast evolving advances in network and computer technologies and decreasing size and cost of sensors and robots enable us to further extend the MOMR system architecture to incorporate heterogeneous components such as humans, robots, sensors, and automated agents. The requests for controlling robot actuation are generated by all the participants. We term it as the MOMR++ system. However, to reach the best potential and performance of the system, there are many technical challenges needing to be addressed. In this dissertation, we address two major challenges in the MOMR++ system development. We first address the robot coordination and planning issue in the application of an autonomous crowd surveillance system. The system consists of multiple robotic pan-tilt-zoom (PTZ) cameras assisted with a fixed wide-angle camera. The wide-angle camera provides an overview of the scene and detects moving objects, which are required for close-up views using the PTZ cameras. When applied to the pedestrian surveillance application and compared to a previous work, the system achieves increasing number of observed objects by over 210% in heavy traffic scenarios. The key issue here is given the limited number (e.g., p (p > 0)) of PTZ cameras and many more (e.g., n (n >> p)) observation requests, how to coordinate the cameras to best satisfy all the requests. We formulate this problem as a new camera resource allocation problem. Given p cameras, n observation requests, and [epsilon] being approximation bound, we develop an approximation algorithm running in O(n/[epsilon]³ + p²/[epsilon]⁶) time, and an exact algorithm, when p = 2, running in O(n³) time. We then address the automatic object content analysis and recognition issue in the application of an autonomous rare bird species detection system. We set up the system in the forest near Brinkley, Arkansas. The camera monitors the sky, detects motions, and preserves video data for only those targeted bird species. During the one-year search, the system reduces the raw video data of 29.41TB to only 146.7MB (reduction rate 99.9995%). The key issue here is to automatically recognize the flying bird species. We verify the bird body axis dynamic information by an extended Kalman filter (EKF) and compare the bird dynamic state with the prior knowledge of the targeted bird species. We quantify the uncertainty in recognition due to the measurement uncertainty and develop a novel Probable Observation Data Set (PODS)-based EKF method. In experiments with real video data, the algorithm achieves 95% area under the receiver operating characteristic (ROC) curve. Through the exploration of the two MOMR++ systems, we conclude that the new MOMR++ system architecture enables much wider range of participants, enhances the collaboration and interaction between participants so that information can be exchanged in between, suppresses the chance of any individual bias or mistakes in the observation process, and further frees humans from the control/observation process by providing automatic control/observation. The new MOMR++ system architecture is a promising direction for future telerobtics advances.

The enforcement of reusability and shareability of products or components based on new technology standards for simulation and modeling is of paramount importance. In this thesis we first utilize DMSO HLA as the basic fundamental to design a customization environment for Web-based modeling and simulation. The environment is able to offer the interoperability framework between a broad spectrum of simulation paradigms, including both real-time and logical time models and to support a huge number of participants. To fulfill the goal we proposed three main tasks to be done. First, we proposed the mechanism to reduce the communication overhead and to balance the information consistency among large participants by incorporating a three-level control mechanism and Dynamic Filtering Strategy (DFS) within HLA RTI. In the second task, we proposed a load balancing algorithm to efficiently utilize the resource over the network environment. At the last task we use Java 3D to build a virtual reality application on the environment.

A control system in which sensors, actuators, and controllers are interconnected over a communication network is called a networked control system (NCS). Enhanced computational capabilities and bandwidths in the networking technology enabled researchers to develop NCSs to implement distributed control schemes. This dissertation presents a framework for the modeling, design, stability analysis, control, and bandwidth allocation of real-time control over networks. This framework covers key research issues regarding control over networks and can be the guidelines of NCS design. A single actuator ball magnetic-levitation (maglev) system is implemented as a test bed for the real-time control over networks to illustrate and verify the theoretical results of this dissertation. Experimentally verifying the feasibility of Internet-based real-time control is another main objective of this dissertation. First, this dissertation proposes a novel NCS model in which the effects of the networkinduced time delay, data-packet loss, and out-of-order data transmission are all considered. Second, two simple algorithms based on model-estimator and predictor- and timeout-scheme are proposed to compensate for the network-induced time delay and packet loss simultaneously. These algorithms are verified experimentally by the ball maglev test bed. System stability analyses of original and compensated systems are presented. Then, a novel co-design consideration related to real-time control and network communication is also proposed. The working range of the sampling frequency is determined by the analysis of the system stability and network parameters such as time delay, data rate, and data-packet size. The NCS design chart developed in this dissertation can be a useful guideline for choosing the network and control parameters in the design of an NCS. Using a real-time operating system for real-time control over networks is also proposed as one of the main contributions of this dissertation. After a real-time NCS is successfully implemented, advanced control theories such as robust control, optimal control, and adaptive control are applied and formulated to improve the quality of control (QoC) of NCSs. Finally, an optimal dynamic bandwidth management method is proposed to solve the optimal network scheduling and bandwidth allocation problem when NCSs are connected to the same network and are sharing the network resource.

ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA / This paper analyzed protocols may be used in each layer in networked telemetry systems, and also presents some deeper researches of the advantages of using synchronous time-division for the physical layer of a networked telemetry system.

Game development is a complex and time-consuming activity that requires domain-specific knowledge and implementation skills. Networked games are particularly difficult due to the additional challenges of implementing the distribution. In recent years, game development has been simplified through tools that allow game development based on entities (objects that compose the game, e.g., avatar, vehicles, trees, and monsters). Entity-based tools simplify game programming by providing entity-level constructs and abstractions to the game developer. However, current entity-based tools fail to appropriately address the development of networked multiplayer games; they either do not support network gaming at all, or compromise the purity of the model by exposing low-level network programming to the game developer. In this thesis, we present a pure entity-based model for developing networked multiplayer games. In our model, the game developer is completely shielded from network programming concerns. In order to demonstrate the model’s practicality, we implemented a game development toolkit called Meerkat. Meerkat uses a combination of generic distribution algorithms and a proxy-based architecture to provide a pure entity-based game programming interface. The same interface can be used to develop both distributed and non-distributed games. Meerkat automates all aspects of networking for the game developer. To evaluate the performance of our system, we built three multiplayer games of different genres. Our experiments show that the overhead of using fully-automated networking can be acceptable for a wide range of games, except in extreme cases where there are strict performance requirements. Meerkat demonstrates that it is possible to extend the pure entity-based approach to networked games while ensuring sufficient performance. / Thesis (Master, Computing) -- Queen's University, 2012-08-29 14:54:00.647