The development and flight operation of a 22 N to 89 N (5 lbf to 20 lbf) O2/CH4 rocket engine is discussed herein. The Roll Control Engine (RCE) was designed by NASA JSC for the Project Morpheus flying vertical test bed and is fully integrated with the Morpheus main engine. Morpheus is a NASA Advanced Exploration System (AES) Project lead out of JSC. Several iterations of the RCE design have resolved some technical problems which are described in the present work. Over 20 flight tests have demonstrated that the Roll Control System (RCS) engines are reliable, capable of operation over a wide range of pressures (2400 kPa to 1000 kPa or 350 psig to 150 psig) and propellant temperatures (gas to liquid), and meet the control requirements for the vehicle. Information regarding ground turnaround and flight operational experience in the earth atmospheric environment is presented. The purpose of this work is to disseminate the knowledge that Project Morpheus has gained through research and development of this engine.Nomenclature Soff = FDIR fail off strike Ft = thrust force Isp = specific impulse Pc = chamber pressure Pin = engine inlet pressure Ptank = propellant tank pressure Q = volumetric flow rate Tin = engine inlet fluid temperature Tnoz = nozzle outer skin temperature Tsat = saturation temperature Ttank = propellant tank fluid temperature Vb = RCS bleed valve open command Vm = RCE main valve open command Acronyms CFM = cryogenic fluid management CG = center of gravity CNTRL = Morpheus control software EMI = electromagnetic interference FDIR = fault detection, isolation, and reconfiguration FFC = fuel film cooling ISRU = in-situ resource utilization MIB = minimum impulse bit MR = mass mixture ratio PCAD = propulsion and cryogenics advanced development PROP = Morpheus propulsion software RCE = roll control engine RCS = roll control system 1 Morpheus RCS Lead, Propulsion Branch, EP4, and AIAA Member.

Many Minnesota counties are faced with the problem of high vehicle speeds through towns or resort areas that have significant pedestrian traffic. The impact of speed reduction strategies in high-pedestrian areas in rural counties of Minnesota was investigated. Speed data were collected at two selected study sites under their existing conditions ("no-treatment" or "before" condition) and after the proposed speed reduction strategies were installed. Second "after" data conditions were collected to study the short-term and long-term impact of the implemented strategies. The traffic-calming techniques employed at the Twin Lakes site consisted of removable pedestrian islands and pedestrian crossing signs. A dynamic variable message sign that sent a single-word message ("Slow") to motorists traveling over the speed limit was installed at the Bemidji site. The research study shows that the traffic-calming strategy deployed in Twin Lakes was effective in significantly reducing the mean speed and improving speed limit compliance in both the short term and long term. Despite proven effectiveness, the deployed speed reduction treatment in Bemidji Lake failed to lower the speed at the study site. The single-word message on the sign and the location of the sign, as well as a lack of initial enforcement, were the primary reasons for such failure.

or several years, the U.S. Federal Highway Administration (FHWA) Office of Transportation Operations Road Weather Management Program has been involved in the development of a guidance tool for winter road maintenance decision makers. The tool, known as the maintenance decision support system (MDSS), is the culmination of work by a consortium of national laboratories, directed by FHWA with feedback from both the state departments of transportation and the private sector. The MDSS combines advanced weather and road condition prediction with automated rules of practice to produce a customized and optimized set of treatment recommendations for winter road maintenance managers. The potential payoff is higher mobility and safety on roadways, and more efficient and cost-effective use of staff, equipment, and chemicals. The latter would produce a reduced impact on the environment. This paper describes the history, development, and status of the MDSS project. Preliminary results and lessons learned from a field demonstration, future development efforts, and the technology transfer plan is discussed.

The 2003 Iowa General Assembly asked the Iowa Department of Transportation (DOT) to conduct a study of Iowa public policy on coordination of public transit services and school transportation. The legislature's request, contained in the transportation appropriation bill, required “a report pertaining to the efficiencies that may be gained by the coordination of transit management and maintenance systems in the areas of school transportation, public transit, and other forms of public transportation.” Such efficiencies are described. As requested by the Iowa DOT, the Center for Transportation Research and Education at Iowa State University studied these issues and prepared a report for the Office of Public Transit. A summary of the coordination activities that are taking place in Iowa between the school districts and transit agencies is presented. Furthermore, the levels of coordination and what benefits are derived from coordinating services are discussed. The objectives of the study include the following: to examine the legal basis for such coordination in Iowa; to inventory the types of coordination taking place around the state; and to highlight some of the coordination models, with a discussion of what each party believes are the benefits of the coordination as well as obstacles that have been encountered.

The high-potential of lightweight components consisting of similar or dissimilar materials can be exploited by Solid-State Joining techniques. Whereas defects such as pores and hot cracking are often an issue in fusion-based joining processes, via solid-state joining processes they can be avoided to enable high-quality welds. To define an optimal process window for obtaining anticipated joint properties, numerous time and cost consuming experiments are usually required. Building a predictive model based on regression analysis enables the identification and quantification of process-property relationships. On the one hand, mechanical property and performance predictions based on specific process parameters are needed, on the other hand, inverse determination of required process parameters for reaching desired properties or performances are demanded. If these relations are obtained, optimized process parameter sets can be identified while vast numbers of required experiments can be reduced, as underlying physical mechanisms are utilized. In this study, different regression analysis algorithms, such as linear regression, decision trees and random forests, are applied to the refill Friction Stir Spot Welding process for establishing correlations between process parameters and joint properties. Experimental data sets used for training and testing are based on a Box-Behnken Design of Experiments (DoE) and additional test experiments, respectively. The machine-learning based regression analyses are benchmarked against linear regression and DoE statistics. The results illustrate a decryption of relationships along the process-property chain and its deployment to predict mechanical properties governed by process parameters.