The paper presents a framework for interactive control of multi robots using mixed reality interfaces. The proposed approach can operate with both single and multi-robot systems, including ...interaction with industrial manipulators, mobile robots, and unmanned aerial vehicles (UAV). The human-robot interface allows both interactive and physical interaction with the robot. Particular attention is paid to a visualisation of the robots' intent during control. The presented framework has Robotic Operation System (ROS) as a core that can be connected to any robot and mixed reality interface. This allows us to make framework scalable and connect several different mixed reality devices and multiple heterogeneous robots. In the implementation part we connected our framework with Microsoft HoloLens, collaborative robot KUKA IIWA, mobile platform Plato, UAV designed on the basis of dji f450. The proposed framework was tested experimentally with real experimental setups mentioned above. The results showed the capabilities of the mixed reality system for interactive control of different robots' type.
MicroBooNE is a 170 ton Liquid Argon Time Projection Chamber (LArTPC) experiment located at Fermi National Accelerator Laboratory. It has been operating in the Booster neutrino beam since October ...2015 and is already demonstrating the superb imaging capabilities of LArTPC detectors. MicroBooNE is the first large LArTPC detector to be exposed to a high-intensity neutrino beam. Among its primary physics goals are precise measurements of muon neutrino charged-current (CC) interactions on argon. In order to analyse its high-statistics data, a suite of fully automated techniques have been developed that reconstruct the LArTPC images and separate muon neutrino CC interactions from their cosmic-ray and neutral current backgrounds. These proceedings will describe the reconstruction and selection of muon neutrino CC event candidates, and present measured distributions of the observed events based on 5e19 protons on target from the first MicroBooNE data-taking period.
Localization or positioning of a landing platform is one of the most important problems for autonomous navigation. In this work, a system of visual positioning of a multirotor unmanned aerial vehicle ...is proposed, which allows landing an unmanned aerial vehicle in autonomous mode. In contrast to general approaches, the system developed is able to work independently of the time of day and weather conditions. The proposed method also permits determining the position and orientation of the platform using a camera and a specialized system of independent color markers. The system uses a monocular camera with low exposition time for extracting the position of user markers with different colors. Then points of the markers are united into groups. Finally, localization of the landing platform is determined by the distance and orientation of each group regarding the center of the platform.
A mixed landscape irrigation study was conducted on 27 residential sites in Las Vegas to quantify water savings associated with satellite irrigation controllers. Seventeen sites were equipped with ...evapotranspiration-based (ET) satellite irrigation controllers and ten sites were designated as control sites and retrofitted with nonET-based irrigation controllers. Results showed that 13 of 16 ET-based controller sites saved water compared to four of ten of the nonET-based control sites. When all control sites were grouped together, a statistical difference occurred between the control and ET-based groups (ET-based controller=
+20%
savings)
(p<0.05)
. Results from this study indicated that water savings were not because of deficit irrigations at the expense of the landscape plant material. Eighty-one percent of the variation in the total outdoor water use could be described by the total turfgrass area at each site. Such results would suggest that turfgrass limitations have merit, if the grass being restricted is tall fescue growing in an arid environment.
Fate of selenium in a small urban watershed Devitt, D. A; Wright, L. E; Shanahan, S. A ...
Environmental monitoring and assessment,
05/2014, Letnik:
186, Številka:
5
Journal Article
Recenzirano
A field study was conducted on a small urban watershed (residential and golf course dominated) in southern Nevada to assess the concentration and speciation of selenium (Se) in a series of drain ...lines and monitoring wells and to quantify the mass discharge of Se from the drain system. Water samples were collected on a monthly basis and analyzed for total Se, selenate (SeO₄ ⁼) and selenite (SeO₃ ⁼). In addition, where possible, flow was assessed as was, temperature, redox potential, pH, dissolved oxygen (DO) along with all major cations and anions. The data were then modeled with PhreeqC to identify selenium speciation. Results revealed a SeO₄ ⁼ dominated system with SeO₄ ⁼ concentrations ranging from 13 to 62 ppb. In the monitoring wells, 66 % of the variation in the total Se concentration could be described based on depth to groundwater, temperature and sulfate concentrations (P < 0.001). In particular, higher total Se concentrations were predicted for shallower depth to groundwater, suggesting the solubilization of Se evapo-concentrates near the surface could be reduced by lowering water tables. The highest of all correlations was found between SeO₄ ⁼ concentrations (↑) and the sodium (↑) and DO (↑) concentrations in the monitoring wells (R ² = 0.77, P < 0.001). An excellent curvilinear relationship was found between total Se and the electrical conductivity in the water (R ² = 0.73, P < 0.001). Based on the Se data and time line identified in this study, high concentrations of Se could be expected to drain from this area for many years to come, with salinity acting as a good proxy for Se concentration. In the drain lines, Se concentrations were found to be invariant to flow (P > 0.05). Flow discharge from the main drain system to the Las Vegas Wash was estimated at 559 acre feet during the 1 year study period. This flow was estimated to carry 4,203 Mg of salts 6.71 Mg of nitrate-N and 27.1 kg of total Se.
A 4-yr study was conducted to assess the impact of reuse water on soil salinization of nine golf courses in southern Nevada: three long-term reuse courses, three fresh-water courses, and three ...courses that transitioned to reuse water during the experimental period. Four of nine fairways had positive leaching fractions (LFs) during all 4 yr, with statistical separation occurring based on 4-yr averages (p < 0.001). Soil salinity levels followed a sinusoidal seasonal curve, with 70% of all peaks associated with summer months. Salinity contour maps (surface soil) were compared over time. More than 85% of the surface area of greens were mapped as electrical conductivity of saturation extract (ECe) < 4.0 dS m-1, whereas 64% of the fairways were mapped at ECe < 4.0 dS m-1. This salinity relationship dropped to 13% on fairways of long-term reuse courses. Changes in the average ECe values after transition to reuse water were primarily driven by the number of days a course had been irrigated with reuse water (R2 = 0.69***). Depth-averaged salinity (sensors) was found to be highly correlated with LF on reuse courses (R2 = 0.86***) and transitional courses (R2 = 0.87***). Yearly changes in depth-averaged sensor values on transitional courses were described by an equation that included the number of days a golf course was irrigated with reuse water, the LF, and the uniformity of the irrigation system (R2 = 0.83***). Although deficit irrigating can be practiced for short periods, adequate LFs are essential for the long-term success of golf courses irrigated with reuse water.
The effect of brine marination at chill temperatures on survival and growth of spoilage and pathogenic bacteria during processing and subsequent storage of ready-to-eat cold water shrimp was studied. ...Survival and growth of Lactobacillus sakei, Listeria monocytogenes, Salmonella, Staphylococcus aureus and Vibrio parahaemolyticus were examined. The effect of brine composition and pH was determined in 12 screening experiments without addition of shrimp. Sixteen challenge tests with shrimp were then carried out to examine the effect of brine composition and storage temperature on survival and growth during processing and subsequent storage of brined and drained shrimp in modified atmosphere packaging (MAP). Different brines with (i) acetic and lactic acids (AL) or (ii) benzoic, citric and sorbic acids (BCS) were studied. V. parahaemolyticus was inactivated in brine AL without shrimp whereas concentrations of all the examined microorganisms were reduced in brine BCS. A significant effect of brine pH on inactivation was observed and inactivation during chill marination of shrimp in brine was reduced compared to the effect of brine alone. This was explained by a relatively fast increase of pH in the brine during marination of shrimp. For shrimp in brine BCS, reductions were observed for V. parahaemolyticus and Salmonella, whereas inactivation in shrimp was only noticed for Salmonella in brine AL. The observed reductions were too small to be used in practise for decontamination of shellfish. None of the examined pathogens was able to grow at 7°C in brined and drained MAP shrimp that resembled commercial products. However, reducing the concentration of acetic and lactic acids by 50% resulted in relatively fast growth of L. monocytogenes in brined and drained MAP shrimp at 7°C. Growth of S. aureus and Salmonella was observed in similar products stored at 15°C. V. parahaemolyticus was reduced in brined and drained MAP shrimp stored at both 7 and 15°C. Based on the results of the present study, L. monocytogenes was identified as the greatest potential risk with respect to the safety of brined and drained MAP shrimp. The potential of L. sakei as spoilage bacterium in brined and drained MAP shrimp was confirmed. Importantly, growth rates of L. sakei and L. monocytogenes in brined and drained MAP shrimp were predicted accurately by available mathematical models. Thus, these models can be used for product development and establishment of shell-life for ready-to-eat shrimp taking into account both quality and safety aspects.
► Brine marination is insufficient as a method for decontamination of shrimp. ► L. monocytogenes is the greatest risk with respect to the safety of RTE shrimp. ► Growth of L. monocytogenes and L. sakei was accurately predicted.
A two-year study was conducted in 2002 and 2003 at the University of Nevada, Las Vegas's center for urban water conservation to assess canopy spectral response of annual ryegrass (Lolium multiflorum ...Lam.) grown under various combinations of N and irrigation (based on leaching fraction: LF) treatments. Multispectral measurements were acquired using a ground-based spectroradiometer (200-1100 nm) on a biweekly basis during the growing season (October-May) in 2002 and 2003. Multispectral parameters were correlated with soil-plant parameters and temporal variability was investigated. Results showed that the normalized difference vegetation index (NDVI), stress index (SI), photochemical reflectance index (PRI) and canopy reflectance at 693 nm, were highly correlated with tissue N concentration (TN), tissue moisture content (TM), TN×TM and canopy colour, as influenced by N and LF treatment combinations. Coefficients of determination ranged from 0.50 to 0.79 (P<0.001) based on single-day correlations and correlations established over the entire growing period in 2002 and in 2003. TN was mainly predicted from wavelengths in the VIS portion of the spectrum, while TM was predicted from wavelengths in the VIS and NIR. Correlations were inconsistent between spectral parameters and physiological parameters throughout the study confirming the problem of temporal variation associated with spectral signatures of turfgrass species. However, spectral reflectance showed significant potential for monitoring turfgrass N and moisture status, and was able to capture temporal variability over the same growing period and from one year to another. The results provide a sound basis for future validation of ground-based remote sensing for turfgrass management on golf courses.
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