2,534 research outputs found

    Correction of Measurement Error in Monthly USDA Pig Crop: Generating Alternative Data Series

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    The imputed pig death loss contained in the reported monthly U.S. Department of Agriculture (USDA) pig crop data over the December 1995–June 2006 period ranged from 24.93% to 12.75%. Clearly, there are substantial measurement errors in the USDA monthly pig crop data. In this paper, we present alternative monthly U.S. pig crop data using the biological production process, which is compatible with prior knowledge of the U.S. hog industry. Alternative pig crop data are applied to a slaughter hog model and tested comparatively to USDA pig crop. Test results reject the validity of USDA pig crop data in favor of the alternative data.biological production process, measurement error, monthly USDA pig crop data, pig death loss, Agribusiness, Farm Management, Livestock Production/Industries, Q11, Q13, C12,

    Dynamical friction for accelerated motion in a gaseous medium

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    Dynamical friction arises from the interaction of a perturber and the gravitational wake it excites in the ambient medium. This interaction is usually derived assuming that the perturber has a constant velocity. In realistic situations, motion is accelerated as for instance by dynamical friction itself. Here, we study the effect of acceleration on the dynamical friction force. We characterize the density enhancement associated with a constantly accelerating perturber with rectilinear motion in an infinite homogeneous gaseous medium and show that dynamical friction is not a local force and that its amplitude may depend on the perturber's initial velocity. The force on an accelerating perturber is maximal between Mach 1 and Mach 2, where it is smaller than the corresponding uniform motion friction. In the limit where the perturber's size is much smaller than the distance needed to change the Mach number by unity through acceleration, a subsonic perturber feels a force similar to uniform motion friction only if its past history does not include supersonic episodes. Once an accelerating perturber reaches large supersonic speeds, accelerated motion friction is marginally stronger than uniform motion friction. The force on a decelerating supersonic perturber is weaker than uniform motion friction as the velocity decreases to a few times the sound speed. Dynamical friction on a decelerating subsonic perturber with an initial Mach number larger than 2 is much larger than uniform motion friction and tends to a finite value as the velocity vanishes in contrast to uniform motion friction.Comment: Published in MNRAS. Revised version (minor typos corrected

    Using Crowdsourced Vehicle Braking Data to Identify Roadway Hazards

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    Modern vehicles know more about the road conditions than transportation agencies. Enhanced vehicle data that provides information on “close calls” such as hard braking events or road conditions during winter such as wheel slips and traction control will be critical for improving safety and traffic operations. This research applied conflict analyses techniques to process approximately 1.5 million hard braking events that occurred in the state of Indiana over a period of one week in August 2019. The study looked at work zones, signalized intersections, interchanges and entry/exit ramps. Qualitative spatial frequency analysis of hard-braking events on the interstate demonstrated the ability to quickly identify temporary and long-term construction zones that warrant further investigation to improve geometry and advance warning signs. The study concludes by recommending the frequency of hard-braking events across different interstate routes to identify roadway locations that have abnormally high numbers of “close calls” for further engineering assessment

    Gravitational Potential Environment of Galaxies: I. Simulation

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    We extend the concept of galaxy environment from the local galaxy number density to the gravitational potential and its functions like the shear tensor. For this purpose we examine whether or not one can make an accurate estimation of the gravitational potential from an observational sample which is finite in volume, biased due to galaxy biasing, and subject to redshift space distortion. Dark halos in a Λ\LambdaCDM simulation are used in this test. We find that one needs to stay away from the sample boundaries by more than 30h1h^{-1}Mpc to reduce the error within 20% of the root mean square values of the potential or the shear tensor. The error due to the galaxy biasing can be significantly reduced by using the galaxy mass density field instead of the galaxy number density field. The error caused by the redshift space distortion can be effectively removed by correcting galaxy positions for the peculiar velocity effects. We inspect the dependence of dark matter halo properties on four environmental parameters; local density, gravitational potential, and the ellipticity and prolateness of the shear tensor. We find the local density has the strongest correlation with halo properties. This is evidence that the internal physical properties of dark halos are mainly controlled by small-scale physics. In high density regions dark halos are on average more massive and spherical, and have higher spin parameter and velocity dispersion. In high density regions dark halos are on average more massive and spherical, and have higher spin parameter and velocity dispersion. We also study the relation between the environmental parameters and the subtypes of dark halos. The spin parameter of satellite halos depends only weakly on the local density for all mass ranges studied while that of isloated or central halos depends more sensitively on the local density. (abridged)Comment: 12 pages, 11 figures, ApJ in press, Full resolution preprint available at this http URL (http://astro.kias.re.kr/~kjhan/0904Potent/ms.pdf

    The Grizzly, December 5, 2019

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    Ursinus Cancels Swimming Seasons After Hazing Investigation • Students Detail Harassment on Main Street • Summer Internship Tips with CPD • Get to Know: Spring Break Service Trip • Opinion: Ursinus\u27 Judicial System is Broken • Q&A with Senior Linebacker Jake McCain • Women\u27s Basketball Walk-on Proves She is More Than Just a Ballerhttps://digitalcommons.ursinus.edu/grizzlynews/1597/thumbnail.jp

    11 x 11 Domineering is Solved: The first player wins

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    We have developed a program called MUDoS (Maastricht University Domineering Solver) that solves Domineering positions in a very efficient way. This enables the solution of known positions so far (up to the 10 x 10 board) much quicker (measured in number of investigated nodes). More importantly, it enables the solution of the 11 x 11 Domineering board, a board up till now far out of reach of previous Domineering solvers. The solution needed the investigation of 259,689,994,008 nodes, using almost half a year of computation time on a single simple desktop computer. The results show that under optimal play the first player wins the 11 x 11 Domineering game, irrespective if Vertical or Horizontal starts the game. In addition, several other boards hitherto unsolved were solved. Using the convention that Vertical starts, the 8 x 15, 11 x 9, 12 x 8, 12 x 15, 14 x 8, and 17 x 6 boards are all won by Vertical, whereas the 6 x 17, 8 x 12, 9 x 11, and 11 x 10 boards are all won by Horizontal

    Changing healthcare professionals' behaviors to eliminate disparities in healthcare: What do we know? How might we proceed?

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    The patient-healthcare provider communication process--particularly the provider's cultural competency--is increasingly recognized as a key to reducing racial/ethnic disparities in health and healthcare utilization. A working group was formed by the Office of Minority Health, Department of Health and Human Services to identify strategies for improving healthcare providers' cultural competency. This expert panel, one of several working groups called together to explore methods of reducing healthcare disparities, was comprised of individuals from academic medical centers and health professional organizations who were nationally recognized as having expertise in healthcare communication as it relates to diverse populations. During the 2-day conference, the panel identified, from personal experience and knowledge of the literature, key points of intervention and interventions most likely to improve the cross-cultural competency of healthcare providers. Proposed interventions included introduction of cultural competence education before, during, and after clinical training; implementation of certification and accreditation requirements in cross-cultural competence for practicing healthcare providers; use of culturally diverse governing boards for clinical practices; and active promotion of workforce cross-cultural diversity by healthcare organization administrators. For each intervention, methods for implementation were specified. On-going monitoring and evaluation of processes of care using race/ethnicity data were recommended to ensure the programs were functioning

    Adrenalectomy for Metastatic Disease to the Adrenal Gland from Gastric Cancer: Report of a Case

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    Metastases to the adrenal glands are frequently found at autopsy. In practice, adrenal metastases have generally been accepted as evidence of blood-borne systemic disease. So, clinically curable adrenal metastases is a rare malady. The role for surgical resection in adrenal metastases has not been clearly defined. A 45-year-old man initially underwent total gastrectomy with D2 lymph node dissection for treating his advanced gastric cancer. A solitary adrenal metastases was resected 1 year later. The patient has survived for 3 years and no further evidence of disease was found on his last follow-up examination. We report here on this case to show that for selected cases, surgical resection of adrenal metastases is feasible and this procedure may extend survival for metastatic gastric cancer patients

    Dashboards for Real-time Monitoring of Winter Operations Activities and After-action Assessment

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    The Indiana Department of Transportation (INDOT) operates a fleet of nearly 1100 snowplows and spends up to $60M annually on snow removal and de-icing as part of their winter operation maintenance activities. Systematically allocating resources and optimizing material application rates can potentially save revenue that can be reallocated for other roadway maintenance operations. Modern snowplows are beginning to be equipped with a variety of Mobile Road Weather Information Sensors (MARWIS) which can provide a host of analytical data characterizing on-the-ground conditions during periods of wintry precipitation. Traffic speeds fused with road conditions and precipitation data from weather stations provide a uniquely detailed look at the progression of a winter event and the performance of the fleet. This research uses a combination of traffic speeds, MARWIS and North American Land Data Assimilation System (NLDAS) data to develop real-time dashboards characterizing the impact of precipitation and pavement surface temperature on mobility. Twenty heavy snow events were identified for the state of Indiana from November 2018 through April 2019. Two particular instances, that impacted 182 miles and 231 miles of interstate at their peaks occurred in January and March, respectively, and were used as a case study for this paper. The dashboards proposed in this paper may prove to be particularly useful for agencies in tracking fleet activity through a winter storm, helping in resource allocation and scheduling and forecasting resource needs

    Extraction of Vehicle CAN Bus Data for Roadway Condition Monitoring

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    Obtaining timely information across the state roadway network is important for monitoring the condition of the roads and operating characteristics of traffic. One of the most significant challenges in winter roadway maintenance is identifying emerging or deteriorating conditions before significant crashes occur. For instance, almost all modern vehicles have accelerometers, anti-lock brake (ABS) and traction control systems. This data can be read from the Controller Area Network (CAN) of the vehicle, and combined with GPS coordinates and cellular connectivity, can provide valuable on-the-ground sampling of vehicle dynamics at the onset of a storm. We are rapidly entering an era where this vehicle data can provide an agency with opportunities to more effectively manage their systems than traditional procedures that rely on fixed infrastructure sensors and telephone reports. This data could also reduce the density of roadway weather information systems (RWIS), similar to how probe vehicle data has reduced the need for micro loop or side fire sensors for collecting traffic speeds
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