19 research outputs found
Robotic Wireless Sensor Networks
In this chapter, we present a literature survey of an emerging, cutting-edge,
and multi-disciplinary field of research at the intersection of Robotics and
Wireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor
Networks (RWSN). We define a RWSN as an autonomous networked multi-robot system
that aims to achieve certain sensing goals while meeting and maintaining
certain communication performance requirements, through cooperative control,
learning and adaptation. While both of the component areas, i.e., Robotics and
WSN, are very well-known and well-explored, there exist a whole set of new
opportunities and research directions at the intersection of these two fields
which are relatively or even completely unexplored. One such example would be
the use of a set of robotic routers to set up a temporary communication path
between a sender and a receiver that uses the controlled mobility to the
advantage of packet routing. We find that there exist only a limited number of
articles to be directly categorized as RWSN related works whereas there exist a
range of articles in the robotics and the WSN literature that are also relevant
to this new field of research. To connect the dots, we first identify the core
problems and research trends related to RWSN such as connectivity,
localization, routing, and robust flow of information. Next, we classify the
existing research on RWSN as well as the relevant state-of-the-arts from
robotics and WSN community according to the problems and trends identified in
the first step. Lastly, we analyze what is missing in the existing literature,
and identify topics that require more research attention in the future
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Portable fluorometric monitor to detect polynuclear aromatic hydrocarbon contamination of work area surfaces
A hand-held fluorometric monitor for detection of surface contamination by polynuclear aromatic (PNA) compounds is described. The instrument will indicate the presence of microgram quantities of PNA in the workplace at distances less than or equal to 1 m. Laboratory test data using coal liquefaction products and wastes are presented. It is anticipated that this type of spotter will be used extensively in monitoring for PNA contamination of the clean areas of coal conversion facilities, such as lunch rooms, shops, changing facilities, the control room, etc. Actual field evaluation of two spotter units at several coal conversion pilot plants is scheduled to begin during FY 1980
Aryl hydrocarbon mono-oxygenase activity in human lymphocytes
Aryl hydrocarbon mono-oxygenase (AHM), an enzyme of key importance in metabolism of xenobiotic chemicals such as polynuclear aromatic hydrocarbons (PNA), is present in human lymphocytes. Studies investing the relation of activity of AHM in human lymphocytes to parameters such as disease state, PNA exposure, in vitro mitogen stimulation, etc. have been summarized in this report. Some studies have demonstrated increased AHM activity in lymphocytes from cigarette smokers (compared to nonsmokers), and in lung cancer patients when compared to appropriate control groups. These observations are confused by extreme variability in human lymphocyte AHM activities, such variability arising from factors such as genetic variation in AHM activity, variation in in vitro culture conditions which affect AHM activity, and the problematical relationship of common AHM assays to actual PNA metabolism taking place in lymphocytes. If some of the foregoing problems can be adequately addressed, lymphocyte AHM activity could hold the promise of being a useful biomarker system for human PNA exposure
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Pellet fueling development at Oak Ridge National Laboratory
A pellet injector development program has been under way at the Oak Ridge National Laboratory (ORNL) since 1976 with the goals of developing D/sub 2/, T/sub 2/ pellet fuel injectors capable of reliable repetitive fueling of reactors and of continued experimentation on contemporary plasma devices. The development has focused primarily on two types of injectors that show promise. One of these injectors is the centrifuge-type injector, which accelerates pellets in a high speed rotating track. The other is the gas or pneumatic gun, which accelerates pellets in a gun barrel using compressed helium of H/sub 2/ gas
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Performance characterization of pneumatic single pellet injection system
The Oak Ridge National Laboratory single-shot pellet injector, which has been used in plasma fueling experiments on ISX and PDX, has been upgraded and extensively instrumented in order to study the gas dynamics of pneumatic pellet injection. An improved pellet transport line was developed which utilizes a 0.3-cm-diam by 100-cm-long guide tube. Pellet gun performance was characterized by measurements of breech and muzzle dynamic pressures and by pellet velocity and mass determinations. Velocities up to 1.4 km/s were achieved for intact hydrogen pellets using hydrogen propellant at 5-MPa breech pressure. These data have been compared with new pellet acceleration calculations which include the effects of propellant friction, heat transfer, time-dependent boundary conditions, and finite gun geometry. These results provide a basis for the extrapolation of present-day pneumatic injection system performance to velocities in excess of 2 km/s
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Indoor air quality study of forty east Tennessee homes
Over a one-year period, measurements of indoor air pollutants (CO/sub x/, NO/sub x/, formaldehyde, volatile organics, particulates, and radon) were made in 40 homes in East Tennessee. The houses were of various ages with different types of insulation and heating. Over one-half of the houses exceeded the ASHRAE indoor ceiling guideline of 0.1 ppM for formaldehyde on at least one occasion. Over the duration of the study, older houses averaged 0.04 ppM of formaldehyde while houses less than 5 years old averaged 0.08 ppM (P < 0.01). The highest concentration of formaldehyde measured was 0.4 ppM in a new home. Diurnal and seasonal fluctuations in levels of formaldehyde in some homes were as much as twofold and tenfold, respectively. The highest levels of formaldehyde were usually recorded during summer months. The concentration in indoor air of various organics was at least tenfold higher than in outdoor air. Carbon monoxide and nitrgen oxides were usually <2 and <0.02 ppM, respectively, except when gas stoves or kerosene space heaters were operating, or when a car was running in the garage. In 30% of the houses, the annual indoor guideline for radon, 4 pCi/L, was exceeded. The mean radon level in houses built on the ridgelines was 4.4 pCi/L, while houses located in the valleys had a mean level of 1.7 pCi/L (P < 0.01). The factor having the most impact on infiltration was operation of the central duct fan of the heating, ventilation, and air conditioning system. The mean rate of air exchange increased from 0.39 to 0.74 h/sup -1/ when the duct fan was operated (measurements prior to December 1982). This report presents the study design and implementation, describes the monitoring protocols, and provides a complete set of the data collected during the project. 25 references, 29 figures, 42 tables
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Tritium pellet injector design for tokamak fusion test reactor
A tritium pellet injector (TPI) system has been designed for the Tokamak Fusion Test Reactor (TFTR) Q approx. 1 phase of operation. The injector gun utilizes a radial design with eight independent barrels and a common extruder to minimize tritium inventory. The injection line contains guide tubes with intermediate vacuum pumping stations and fast valves to minimize propellant leakage to the torus. The vacuum system is designed for tritium compatibility. The entire injector system is contained in a glove box for secondary containment protection against tritium release. Failure modes and effects have been analyzed, and structural analysis has been performed for most intense predicted earthquake conditions. Details of the design and operation of this system are presented in this paper