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Topology control in sensor networks has been heavily studied recently. Different geometric topologies were proposed to be the underlying network topologies to achieve the sparseness of the communication networks or to guarantee the package delivery of specific routing methods. However, most of the proposed topology control algorithms were only applied to Two-Dimensional (2D) networks where all sensor nodes are distributed in a 2D plane. In practice, the sensor networks are often deployed in 3D space, such as sensor nodes in a forest. This paper seeks to investigate efficient topology control protocols for 3D sensor networks. In our new protocols, we extend several 2D geometric topologies to 3D case, and propose some new 3D Yao-based topologies for sensor networks. We also prove several properties (e.g. bounded degree and constant power stretch factor) for them in 3D space. The simulation results confirm our theoretical proofs for these proposed 3D topologies.

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Research experiences for undergraduates are considered an effective means for increasing student retention and encouraging undergraduate students to continue on to graduate school. However, managing a cohort of undergraduate researchers, with varying skill levels, can be daunting for faculty advisors. We have developed a program to engage students in research and outreach in visualization, virtual reality, networked robotics, and interactive games. Our program immerses students into the life of a lab, employing a situated learning approach that includes tiered mentoring and collaboration to enable students at all levels to contribute to research.Students work in research teams comprised of other undergraduates, graduate students and faculty, and participate in professional development and social gatherings within the larger cohort. Results from our first two years indicate this approach is manageable and effective for increasing students' ability and desire to conduct research.

The development of robust, survivable wireless access networks requires that the performance of network architectures and protocols be studied under normal as well as abnormal operating conditions. The work presented herein has two thrusts. One, we propose the use of overlapping coverage areas and adaptive load-sharing channel allocation schemes as a means to increase mobile network survivability by providing multi-homing at the radio channel level.Two, we describe our simulation approach to survivability analysis. Our simulation environment models realistic teletrafic generated from nonuniform service areas. We model abnormal modes due to network failure or due to teletrafic hot-spots. We use our simulation approach to compare the survivability of our load-sharing protocols to the commonly referenced directed retry protocol.