Let the Tree Bloom: Scalable Opportunistic Routing with ORPL

Routing in battery-operated wireless networks is challenging, posing a tradeoff between energy and latency. Previous work has shown that opportunistic routing can achieve low-latency data collection in duty-cycled networks. However, applications are now considered where nodes are not only periodic data sources, but rather addressable end points generating traffic with arbitrary patterns. We present ORPL, an opportunistic routing protocol that supports any-to-any, on-demand traffic. ORPL builds upon RPL, the standard protocol for low-power IPv6 networks. By combining RPL's tree-like topology with opportunistic routing, ORPL forwards data to any destination based on the mere knowledge of the nodes' sub-tree. We use bitmaps and Bloom filters to represent and propagate this information in a space-efficient way, making ORPL scale to large networks of addressable nodes. Our results in a 135-node testbed show that ORPL outperforms a number of state-of-the-art solutions including RPL and CTP, conciliating a sub-second latency and a sub-percent duty cycle. ORPL also increases robustness and scalability, addressing the whole network reliably through a 64-byte Bloom filter, where RPL needs kilobytes of routing tables for the same task

Distributed Joint Source-Channel Coding With Copula-Function-Based Correlation Modeling for Wireless Sensors Measuring Temperature

Wireless sensor networks (WSNs) deployed for temperature monitoring in indoor environments call for systems that perform efficient compression and reliable transmission of the measurements. This is known to be a challenging problem in such deployments, as highly efficient compression mechanisms impose a high computational cost at the encoder. In this paper, we propose a new distributed joint source-channel coding (DJSCC) solution for this problem. Our design allows for efficient compression and error-resilient transmission, with low computational complexity at the sensor. A new Slepian-Wolf code construction, based on non-systematic Raptor codes, is devised that achieves good performance at short code lengths, which are appropriate for temperature monitoring applications. A key contribution of this paper is a novel Copula-function-based modeling approach that accurately expresses the correlation amongst the temperature readings from colocated sensors. Experimental results using a WSN deployment reveal that, for lossless compression, the proposed Copula-function-based model leads to a notable encoding rate reduction (of up to 17.56%) compared with the state-of-the-art model in the literature. Using the proposed model, our DJSCC system achieves significant rate savings (up to 41.81%) against a baseline system that performs arithmetic entropy encoding of the measurements. Moreover, under channel losses, the transmission rate reduction against the state-of-the-art model reaches 19.64%, which leads to energy savings between 18.68% to 24.36% with respect to the baseline system

Task 10: Research an Alternative Instructional Design Model

Under authority of the Federal Aviation Administration (FAA), the Center of Excellence (COE) Technical Training Human Performance (TTHP) Task 10 research team has prepared a comprehensive technical report and an executive summary for the Air Traffic Organization (ATO) concerning the instructional development (ID) of occupational education and training for Air Traffic (AT) controllers and Technical Operations (TO) technicians. Research included: • Front-end analysis of available FAA courses and government furnished information (GFI), including course-development documentation and associated guidance, policies, and regulations. • Structured and semi-structured data-gathering techniques in cooperation with Instructional Systems Specialists (ISS), ISS Managers, and Requirements personnel. • Informal observations of validation events for Air Traffic training. • Analysis of the relevant literature from academic, government, and industry domains. The executive summary describes the findings and observations of issues directly related to the ID process and potential solutions based on findings from this comparative analysis. The comprehensive report that follows includes these and additional observations and recommendations as well as the project overview, an introduction to best practice research, the research methodology, presentation and analysis of the results, and discussion of the findings and conclusions

Improving Professional Learning Community Structures for Enhanced Professional Practice

ABSTRACT This Change Plan gauges the historical reality of the District ABC professional learning communities (PLC) to gain a better understanding of their past effectiveness and secure recommendations for the future. This Change Plan included a qualitative study conducted with the members of the Instructional Leadership Team (ILT). The ten members of the ILT provided feedback to the PLC Survey. The PLC survey was then coded for general themes and common language. The PLC Survey found that in past practice PLCs were absent within District ABC and collaboration among teachers was inconsistent and ineffective. Based upon the findings of the PLC survey I developed this Change Plan to include the development of PLC behavioral protocols, the creation of PLC collaboration structures, and professional development for PLC leaders

2015-2016 annual effectiveness report 

The South Carolina Commission on Higher Education requires reports on institutional effectiveness from each higher education public institution. These reports include student scores on professional examinations as well as other indicators of institutional effectiveness for programs

Development of Variable Slope Piecewise-Based Brown Symbols for Application to Nonlinear Ambiguity Suppression

In 1962, Palermo used two conjugate Linear Frequency Modulated (LFM) pulses to demonstrate a Non-linear Ambiguity Suppression (NLAS) technique to reduce ambiguous energy in radar returns. Using conjugate LFM pulse coding does not readily extend to larger symbol families and thus is severely limited for M-channel (M\u3e 2) NLAS applications. Larger families of optimal mutually dispersible codes with bigger time bandwidth products are needed to achieve the desired M-fold range ambiguity reduction. Using correlation function the time duration as an optimization metric, the recently proposed Brown\u27s theorem formulates a deterministic process for designing optimal mutually dispersible symbol sets of arbitrary size. The rms time duration performance of digitized Brown symbols is invariant to choice of basis (phase-rate) functions used in the design process, yet improvement in cross-correlation side lobe performance is directly linked to basis function design. This insight provided the impetus for designing and synthesizing a new set of mutually dispersible symbols based on Variable Slope (VS) piecewise basis functions. The resultant VS piecewise-based Brown symbols are used with NLAS processing to demonstrate M-fold ambiguity suppression capability. Despite the presence of two undesired ambiguous signal responses having +24.0 dB more signal power relative to the weaker desired unambiguous signal, the NLAS processor effectively suppressed the ambiguous responses. The desired signal peak NLAS output response was approximately 11.0 dB above the noise floor and undesired ambiguous responses were suppressed an average of 10.0 to 12.0 dB - a net improvement of approximately 21.01 to 22.0 dB

Teacher turnover and school reform: how teacher turnover affects urban secondary school improvement

Teacher turnover in urban public schools has traditionally been associated with school destabilization and is considered adversarial to school improvement and reform efforts. However, the 2009 federal education reform initiative, Race to the Top, endorsed forced teacher turnover at the lowest performing schools as a strategy for recruiting teachers of greater human capital and commitment to student learning. Using qualitative case study methods, this dissertation explored whether teacher turnover affects school reform efforts, and if so, how, by studying teacher turnover at three urban public high schools in New England. The findings revealed that teacher turnover does affect school reform efforts. In two of the three cases studied, teacher turnover contributed to the churn of human capital and to the disruption of social capital. In both of these cases, school reform efforts were negatively affected. In the third case, the potential negative effects of teacher turnover were largely mitigated through advanced planning. The leadership team also demonstrated how carefully controlled internal turnover could be used to advance reform efforts

Application of advanced technology to space automation

Automated operations in space provide the key to optimized mission design and data acquisition at minimum cost for the future. The results of this study strongly accentuate this statement and should provide further incentive for immediate development of specific automtion technology as defined herein. Essential automation technology requirements were identified for future programs. The study was undertaken to address the future role of automation in the space program, the potential benefits to be derived, and the technology efforts that should be directed toward obtaining these benefits

The High School Principal's Perceptions of the Demands, Constraints, and Choices in Their Work as Instructional Leaders

A principal's major role is that of an instructional leader, which, according to research, if done in isolation inhibits his or her effectiveness. Current literature reveals a paucity of research that examines how high school principals balance the demands and constraints of their jobs, while cultivating instructional leadership among their staff. This study described the choices that four high school principals made to focus on instructional leadership, in spite of dealing with the demands and constraints of their jobs. The participating principals have varying years of experience and work in a diverse suburban school district in Maryland. A short survey captured the principals' backgrounds, and face-to-face interviews answered research questions about the demands and constraints of their jobs. The survey used was based on the research work of Rosemary Stewart (1982). The study revealed the principals' perceptions of the instructional and non-instructional demands of their jobs. The researcher used the Maryland Instructional Leadership Framework to categorize the principals' responses as instructional leaders and employed Bolman and Deal's (2006) theoretical paradigm to determine whether the principals used a symbolic, structural, human resources, or political frame to conceptualize their roles and responsibilities. The findings indicate that these four high school principals each took on a distributed leadership approach to instruction. The principals worked closely with assistant principals, department chairpersons, staff development teachers, and other key leaders in their focus on instruction. The principals described the importance of having clear roles and responsibilities for staff and of providing opportunities for staff to develop their abilities through leadership experiences and professional development opportunities. The findings support existing research regarding distributed leadership and the myriad responsibilities of school principals. The findings further support the Code of Maryland Regulations (COMAR), which state that the primary role of the school principal is instructional leadership and asserts that all other non-instructional responsibilities are secondary. This study informs research on the choices that high school principals make to focus on instructional leadership