15,375 research outputs found
Geosciences for Elementary Educators: A Course Assessment
Geosciences for Elementary Educators engages future elementary teachers in a hands-on investigation of topics aligned with the third and fifth grade Earth/Space Science and Scientific Inquiry benchmarks of the Oregon Content Standards. The course was designed to develop the content background of elementary teachers within the framework of the science described in the content standards, to provide an opportunity for future teachers to explore the content area in relation to what takes place in the classrooms of elementary schools, and to initiate a community of learners focused on teaching science to elementary students. The course focused on four themes: the classroom teacher as an activity and curriculum developer using diverse resources to keep the content current and alive; the classroom teacher as educator dealing with the diverse backgrounds of students in a developmentally appropriate manner; the classroom teacher as reflective practitioner exploring the links among pedagogy, content, and student learning; and, the classroom teacher as citizen staying current with emerging policy issues and debates that impact education. In a course where process is extremely important, participants are assessed on what they can do with content and process knowledge through preparing lesson plans, presenting lessons in a simulated classroom environment, and developing a portfolio and journal. Lesson plans demonstrate participant understanding of inquiry, using models, deductive and inductive approaches, links between communication skills and content knowledge, and effective use of technology, including the Internet. For each topic, the mixture of demonstration, experimentation, inquiry, and lecture models are explored through investigation, discovery, and analysis
Estimation of Costs of Phosphorus Removal In Wastewater Treatment Facilities: Adaptation of Existing Facilities
As part of a wider enquiry into the feasibility of offset banking schemes as a means to implement pollutant trading within Georgia watersheds, this is the second of two reports addressing the issue of estimating costs for upgrades in the performance of phosphorus removal in point-source wastewater treatment facilities. Earlier, preliminary results are presented in Jiang et al (2004) (Working Paper # 2004-010 of the Georgia Water Planning and Policy Center). The present study is much more detailed and employs an advanced software package (WEST®, Hemmis nv, Kortrijk, Belgium) for simulating a variety of treatment plant designs operating under typical Georgia conditions. Specifically, upgrades in performance, in a single step, from a plant working at an effluent limit of less than 2.0 mg/l phosphorus to one working with limits variously ranging between less than 1.0 mg/l to less than 0.05 mg/l phosphorus are simulated and the resulting costs of the upgrade estimated.Five capacities of plant are considered, from 1 MGD to 100 MGD. Three strategic, alternative designs for the facility are considered: the basic activated sludge (AS) process with chemical addition, the Anoxic/Oxic (A/O) arrangement of the AS process, and the Anaerobic/Aerobic/Oxic (A/A/O) arrangement of the AS process. Upgrades in performance are consistent with the logical alternatives for adapting these options. Cost comparisons are made primarily on the basis of the incremental cost of the upgrade, i.e., from the base-case, reference plant to that performing at the higher level, as expressed through the incremental Total Annual Economic Cost (TAEC; in /kg).For the most stringent upgrade, for example, to a plant generating an effluent with less than 0.05 mg/l phosphorus, these marginal costs -- the cost of the additional phosphorus removed as a result of the upgrade -- amount to something of the order of 150-425 $/kg, with the upper bound being associated with the smallest plant configuration (1 MGD). Working Paper Number 2005-001
Concepts and procedures used to determine certain sea wave characteristics
A technique and its application are presented by which wave parameters, critical to spacecraft water impact load analysis, may be determined
White Dwarf Cosmochronology in the Solar Neighborhood
The study of the stellar formation history in the solar neighborhood is a
powerful technique to recover information about the early stages and evolution
of the Milky Way. We present a new method which consists of directly probing
the formation history from the nearby stellar remnants. We rely on the volume
complete sample of white dwarfs within 20 pc, where accurate cooling ages and
masses have been determined. The well characterized initial-final mass relation
is employed in order to recover the initial masses (1 < M/Msun < 8) and total
ages for the local degenerate sample. We correct for moderate biases that are
necessary to transform our results to a global stellar formation rate, which
can be compared to similar studies based on the properties of main-sequence
stars in the solar neighborhood. Our method provides precise formation rates
for all ages except in very recent times, and the results suggest an enhanced
formation rate for the solar neighborhood in the last 5 Gyr compared to the
range 5 < Age (Gyr) < 10. Furthermore, the observed total age of ~10 Gyr for
the oldest white dwarfs in the local sample is consistent with the early
seminal studies that have determined the age of the Galactic disk from stellar
remnants. The main shortcoming of our study is the small size of the local
white dwarf sample. However, the presented technique can be applied to larger
samples in the future.Comment: 25 pages, 10 figures, accepted for publication in the Astrophysical
Journa
Assessing the Impact of Auditory Peripheral Displays for UAV Operators
A future implementation of unmanned aerial vehicle (UAV) operations is having a single
operator control multiple UAVs. The research presented here explores possible avenues of
enhancing audio cues of UAV interfaces for this futuristic control of multiple UAVs by a single
operator. This project specifically evaluates the value of continuous and discrete audio cues as
indicators of course deviations or late arrivals to targets for UAV missions. It also looks at the
value of the audio cues in single and multiple UAV scenarios.
To this end, an experiment was carried out on the Multiple Autonomous Unmanned Vehicle
Experimental (MAUVE) test bed developed in the Humans and Automation Laboratory at the
Massachusetts Institute of Technology with 44 military participants. Specifically, two continuous
audio alerts were mapped to two human supervisory tasks within MAUVE. One of the
continuous audio alerts, an oscillating course deviation alert was mapped to UAV course
deviations which occurred over a continual scale. The other continuous audio alert tested was a
modulated late arrival alert which alerted the operator when a UAV was going to be late to a
target. In this case the continuous audio was mapped to a discrete event in that the UAV was
either on time or late to a target. The audio was continuous in that it was continually on and
alerting the participant to the current state of the UAV. It either was playing a tone indicating
the UAV was on time to a target or playing a tone indicating the UAV was late to a target. These
continuous alerts were tested against more traditional single beep alerts which acted as discrete
alerts. The beeps were discrete in that when they were used for monitoring course deviations a
single beep was played when the UAV got to specific threshold off of the course or for late
arrivals a single beep was played when the UAV became late.
The results show that the use of the continuous audio alerts enhances a single operator’s
performance in monitoring single and multiple semi-autonomous vehicles. However, the results
also emphasize the necessity to properly integrate the continuous audio with the other auditory
alarms and visual representations in a display, as it is possible for discrete audio alerts to be lost
in aural saliency of continuous audio, leaving operators reliant on the visual aspects of the
display.Prepared for Charles River Analytics, Inc
An Experimental Platform for Investigating Decision and Collaboration Technologies in Time-Sensitive Mission Control Operations
This report describes the conceptual design and detailed architecture of an experimental platform
developed to support investigations of novel decision and collaboration technologies for
complex, time-critical mission control operations, such as military command and control and
emergency response. In particular, the experimental platform is designed to enable exploration
of novel interface and interaction mechanisms to support both human-human collaboration and
human-machine collaboration for mission control operations involving teams of human operators
engaged in supervisory control of intelligent systems, such as unmanned aerial vehicles (UAVs).
Further, the experimental platform is designed to enable both co-located and distributed
collaboration among operations team members, as well as between team members and relevant
mission stakeholders.
To enable initial investigations of new information visualization, data fusion, and data sharing
methods, the experimental platform provides a synthetic task environment for a representative
collaborative time-critical mission control task scenario. This task scenario involves a UAV
operations team engaged in intelligence, surveillance, and reconnaissance (ISR) activities. In the
experimental task scenario, the UAV team consists of one mission commander and three
operators controlling multiple, homogeneous, semi-autonomous UAVs. In order to complete its
assigned missions, the UAV team must coordinate with a ground convoy, an external strike
team, and a local joint surveillance and target attack radar system (JSTARS). This report details
this task scenario, including the possible simulation events that can occur and the logic
governing the simulation dynamics.
In order to perform human-in-the-loop experimentation within the synthetic task environment,
the experimental platform also consists of a physical laboratory designed to emulate a miniature
command center. The Command Center Laboratory comprises a number of large-screen
displays, multi-screen operator stations, and mobile, tablet-style devices. This report details the
physical configuration and hardware components of this Command Center Laboratory. Details
are also provided of the software architecture used to implement the synthetic task environment
and experimental interface technologies to facilitate user experiments in this laboratory.
The report also summarizes the process of conducting an experiment in the experimental
platform, including details of scenario design, hardware and software instrumentation, and
participant training. Finally, the report suggests several improvements that could be made to the
experimental platform based on insights gained from initial user experiments that have been
conducted in this environment.Prepared For Boeing, Phantom Work
Cognitive Task Analysis for the LCS Operator
In support of Plan Understanding for Mixed-initiative control of Autonomous systems (PUMA)The following Tables and Figures detail the cognitive task analysis (CTA) performed to
determine the information requirements needed to support a single operator located aboard the
futuristic Littoral Combat Ship (LCS). This operator is responsible for controlling four
underwater unmanned vehicles in conjunction with a UAV operating on a shared network.
• Table 1 is a scenario task overview that breaks the overall mission into 3 phases
(planning, execution, and recovery) and then details the subtasks for each of the 3
mission phases.
• Figure 1 is an event flow diagram that demonstrates what events must occur in a temporal
order for each of the 3 phases. There are three basic event types in Figure 1: 1) a loop (L)
that represents a process that occurs in a looping fashion until some predetermined event
occurs, 2) a decision (D) that represents some decision that is required from the LCS
operator, and 3) a process (P) which requires some human-computer interaction to
support the required tasks. In each event block, an alphanumeric code is included which
labels that particular event type (L#, D#, P#). This label is important because later
information requirements will be mapped to one of these events.
• Table 2, which details the situation awareness (SA) requirements for the LCS Operator
for each of the 3 mission phases and associated subtasks. Each of these SA requirements
is mapped directly to one or more events in Figure 1.
Because the decisions in Figure 1 represent critical events that require detailed understanding of
what information and knowledge is needed to support the operator’s decision-making process,
decision ladders were constructed for the diamonds and loops in Figure 1 that correspond to an
involved decision process to resolve the question being posed at that stage in the event flow
(Figures 2-4). Decision ladders are modeling tools that capture the states of knowledge and
information-processing activities necessary to reach a decision. Decision ladders can help
identify the information that either the automation and/or the human will need to perform or
monitor a task. Decision Ladders, illustrate the need not only for the same information identified
by the cognitive task analysis, but the need for several other pieces of information such as the
need for visual or aural alerts in contingency situations. In Figures 2-4, three versions are
included that detail (a) the basic decision ladder, (b) the decision ladder with corresponding
display requirements, and (c) the decision ladder with possible levels of automation.
• Figure 2 represents the automated target recognition (ATR) decision ladder (D3 from
Event Flow): (a) decision ladder, (b) decision ladder with corresponding display
requirements, and (c) decision ladder with possible levels of automation.
• Figure 3 shows the decision ladder information and knowledge requirements for the
sentry handoff (L3 from Event Flow).
• Figure 4, the UUV Recovery Decision Ladder (D7 from Event Flow), illustrates what
information is nominally needed. Since this phase was not a major focus, the decision
ladder is not as detailed as it could be. This should be a point of focus in Phase II.
Lastly Figure 5 demonstrates the coordination loop that must occur in the case where a handoff
failure occurs (for a number of reasons to include equipment failure, communication delays, etc.)
Again, because the multi-player coordination issues are not a primary focus in Phase I but are a
significant consideration for any follow-on phases.Prepared for Charles River Analytic
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