3,277 research outputs found

    Generic Techniques for the Calibration of Robots with Application of the 3-D Fixtures and Statistical Technique on the PUMA 500 and ARID Robots

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    A relatively simple, inexpensive, and generic technique that could be used in both laboratories and some operation site environments is introduced at the Robotics Applications and Development Laboratory (RADL) at Kennedy Space Center (KSC). In addition, this report gives a detailed explanation of the set up procedure, data collection, and analysis using this new technique that was developed at the State University of New York at Farmingdale. The technique was used to evaluate the repeatability, accuracy, and overshoot of the Unimate Industrial Robot, PUMA 500. The data were statistically analyzed to provide an insight into the performance of the systems and components of the robot. Also, the same technique was used to check the forward kinematics against the inverse kinematics of RADL's PUMA robot. Recommendations were made for RADL to use this technique for laboratory calibration of the currently existing robots such as the ASEA, high speed controller, Automated Radiator Inspection Device (ARID) etc. Also, recommendations were made to develop and establish other calibration techniques that will be more suitable for site calibration environment and robot certification

    Some aspects of robotics calibration, design and control

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    The main objective is to introduce techniques in the areas of testing and calibration, design, and control of robotic systems. A statistical technique is described that analyzes a robot's performance and provides quantitative three-dimensional evaluation of its repeatability, accuracy, and linearity. Based on this analysis, a corrective action should be taken to compensate for any existing errors and enhance the robot's overall accuracy and performance. A comparison between robotics simulation software packages that were commercially available (SILMA, IGRIP) and that of Kennedy Space Center (ROBSIM) is also included. These computer codes simulate the kinematics and dynamics patterns of various robot arm geometries to help the design engineer in sizing and building the robot manipulator and control system. A brief discussion on an adaptive control algorithm is provided

    Fast-food advertising in social media. A case study on Facebook in Egypt

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    The purpose of this paper is to explore the factors that affect young Egyptian consumers' attitudes towards fast-food advertising in Facebook which is considered the most widely used social media network. 4 focus groups were conducted with young consumers from 2 Egyptian cities. Content analysis was applied for the Egyptian fast-food Facebook fan pages with the aid of the NVivo software. The findings of this exploratory study have shown that young consumers are accepting the idea of fast food advertising in Facebook. Moreover, the research provides a framework for the factors that lead to consumers' engagement with the advertisements on Facebook. With the increase in the popularity of social media websites among the young generation, fast-food marketers find it a more effective medium for advertising for their chains among that segment. The research provides insights for marketers to make their advertisements more effective on Facebook. The participants in the focus groups were young consumers in Egypt. It would be useful to expand the sample and conduct the research in other developing and developed countries with more consumers from other age groups. Consumer attitude towards advertising as a topic generates interest from academics and practitioners in looking at analysis of the effectiveness and success of advertisements in social media. Therefore this research adds value in that, so far, there is very little academic literature on this particular topic examining young Egyptian consumers' attitudes towards fast-food advertising in Facebook

    Further studies of the efficacy of military, commercial and novel skin decontaminants against the chemical warfare agents sulphur mustard, soman and VX

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    Background/Aims: Following an incident involving toxic chemicals, deployment of countermeasures before the arrival of specialised services at the scene may provide a “therapeutic” window in which to mitigate skin absorption. Methods: Five potential candidates (itaconic acid, N,N′-methylenebisacrylamide, 2-trifluoromethylacrylic acid, fuller's earth and Fast-Act®) previously found effective against a simulant (methyl salicylate) were evaluated against a 10 μL droplet of 14C-sulphur mustard (HD), soman (GD) or VX applied to the surface of porcine skin mounted on static skin diffusion cells. Results: All the decontaminants applied to the skin 5 min post exposure achieved a marked reduction in the amount of 14C contaminant remaining within the skin at 24 h. Itaconic acid significantly (p <.05) reduced the amount of 14C-HD, GD and VX remaining in the skin at 24 h. Additionally, 2-trifluoromethylacrylic acid significantly reduced the amount of 14C-HD, whilst fuller's earth significantly reduced the amounts of 14C-HD and VX recovered within the skin at 24 h. Conclusion: All of the products evaluated in this study performed well in reducing the dermal absorption of all the chemical warfare agents tested.Peer reviewe

    Entomological and functional role of floral strips in an organic apple orchard: Hymenopteran parasitoids as a case study

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    Habitat manipulation techniques improve the availability of resources required by natural enemies to increase their effectiveness. This study focused on the effects of floral strips on Hymenopteran parasitoid presence. The experiments were conducted during spring 2007 in one organic low-input apple orchard located in south-eastern France. The density and the diversity of parasitic wasps collected from sown floral strips were higher than those from mown plants. The family of parasitic wasps of Braconidae was strongly dominant, followed by Mymaridae and Pteromalidae. By studying 26 flowering species, the greatest diversity and density of parasitic wasps were collected from Potentilla reptans, Achillea millefolium, Trifolium repens and Torilis arvensis. In terms of the early flowering plants, the most important results were observed in Euphorbia helioscopia, Senecio vulgaris and Veronica persica. To give an idea of the functional role of these plants, we studied the parasitic wasps of the diapausing larvae (cocoon) of codling moth Cydia pomonella. We recorded three emerged species: Ascogaster quadridentata, Pristomerus vulnerator and the hyperparasite Perilampus fulvicornis. However, none of these species have been observed on the 26 studied plants. Hence, this result may be suggesting that the studied plants do not have a functional role concerning these parasitoids. These studies may be advantageous for biological control programs in order to select flowering plant species attracting parasitic wasps specific to fruit pests

    Localization in Long-range Ultra Narrow Band IoT Networks using RSSI

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    Internet of things wireless networking with long range, low power and low throughput is raising as a new paradigm enabling to connect trillions of devices efficiently. In such networks with low power and bandwidth devices, localization becomes more challenging. In this work we take a closer look at the underlying aspects of received signal strength indicator (RSSI) based localization in UNB long-range IoT networks such as Sigfox. Firstly, the RSSI has been used for fingerprinting localization where RSSI measurements of GPS anchor nodes have been used as landmarks to classify other nodes into one of the GPS nodes classes. Through measurements we show that a location classification accuracy of 100% is achieved when the classes of nodes are isolated. When classes are approaching each other, our measurements show that we can still achieve an accuracy of 85%. Furthermore, when the density of the GPS nodes is increasing, we can rely on peer-to-peer triangulation and thus improve the possibility of localizing nodes with an error less than 20m from 20% to more than 60% of the nodes in our measurement scenario. 90% of the nodes is localized with an error of less than 50m in our experiment with non-optimized anchor node locations.Comment: Accepted in ICC 17. To be presented in IEEE International Conference on Communications (ICC), Paris, France, 201

    Structural Changes in the Middle East Stock Markets: The case of Israel and Arab Countries

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    This paper tests for structural changes in the price indices of four stock markets in the Middle East region, namely, Egypt, Turkey Jordan, Morocco and Israel. The Innovational Outlier (IO) model and Additive Outlier (AO) model indicate that all variables show evidence of non-stationarity, I(1), even with structural change. Moreover, the coefficients for all dummy variables such as intercept, slope and time of the break are found to be significant and all have the right signs. The endogenously determined times of the breaks for all variables coincides with observed real events for each country, like Asian crises, fluctuation in oil prices and the political conflict in the Middle East.Structural changes, Middle East stock markets, Israel, Arab countries

    Is Unlevered Firm Volatility Asymmetric?

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    Asymmetric volatility refers to the stylized fact that stock volatility is negatively correlated to stock returns. Traditionally, this phenomenon has been explained by the financial leverage effect. This explanation has recently been challenged in favor of a risk premium based explanation. We develop a new, unlevering approach to document how well financial leverage, rather than size, beta, book-to-market, or operating leverage, explains volatility asymmetry on a firm-by-firm basis. Our results reveal that, at the firm level, financial leverage explains much of the volatility asymmetry. This result is robust to different unlevering methodologies, samples, and measurement intervals. However, we find that financial leverage does not explain index-level volatility asymmetry, which is consistent with theoretical results in Aydemir, Gallmeyer and Hollifield (2006).Volatility asymmetry, Financial leverage, Financial Economics, Research Methods/ Statistical Methods, G12,

    Optimization of Nonambulant Mass Casualty Decontamination Protocols as Part of an Initial or Specialist Operational Response to Chemical Incidents

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    © 2018 The Author(s). Published with license by Taylor & Francis.© 2018 Robert P. Chilcott, Hannah Mitchell, Hazem Matar. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-ncnd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.Objective: The UK's Initial Operational Response (IOR) is a new process for improving the survival of multiple casualties following a chemical, biological, radiological or nuclear incident. Whilst the introduction of IOR represents a patient-focused response for ambulant casualties, there is currently no provision for disrobe and dry decontamination of nonambulant casualties. Moreover, the current specialist operational response (SOR) protocol for nonambulant casualty decontamination (also referred to as “clinical decontamination”) has not been subject to rigorous evaluation or development. Therefore, the aim of this study was to confirm the effectiveness of putatively optimized dry (IOR) and wet (SOR) protocols for nonambulant decontamination in human volunteers. Methods: Dry and wet decontamination protocols were objectively evaluated using human volunteers. Decontamination effectiveness was quantified by liquid chromatography–mass spectrometry analysis of the recovery of a chemical warfare agent simulant (methylsalicylate) from skin and hair of volunteers, with whole-body fluorescence imaging to quantify the skin distribution of residual simulant. Results: Both the dry and wet decontamination processes were rapid (3 and 4 min, respectively) and were effective in removing simulant from the hair and skin of volunteers, with no observable adverse effects related to skin surface spreading of contaminant. Conclusions: Further studies are required to assess the combined effectiveness of dry and wet decontamination under more realistic conditions and to develop appropriate operational procedures that ensure the safety of first responders.Peer reviewe
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