164 research outputs found

    Grooving Pavement Centerlines for Lane Demarcation

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    Lane demarcation is conventionally accomplished by use of white traffic paint placed as a skip line. Most traffic paints are beaded by premixing glass beads in the paint, by drop-on applications, or a combination of the two. The retrodirective properties of the beads greatly enhance nighttime visibility during dry weather; however, visibility of the lines is practically nil during wet nighttime driving. Submerged beads cannot redirect the light when the need for guidance is mosL critical. Thermoplastic striping materials have been used to varying degrees of success by numerous agencies. Wet nighttime visibility of thermoplastics, as experienced in Kentucky, is generally far superior to that of conventional beaded paints. Thermoplastics are placed at a thickness of 125 mils and are thereby less likely to become submerged than conventional paints, which are placed at film thicknesses in the order of 14 mils and dry to approzimately 8 mils. Late in 1965, the California Division of Highways reportedly issued a policy requiring the use of raised pavement markers as a replacement for most painted lines on future freeways and conventional highways. Other agencies have employed raised markers in various forms and have reported excellent to good wet nighttime visibility for markers remaining in place. Major disadvantages of the thermoplastics and raised markers are: they are quite expensive as compared to paint, they break or crack under traffic, and the present loss is high as a result of traffic and snow removal equipment. In addition, the raised markers are rather difficult to install. Christensen Diamond Services, Inc. of Salt Lake City, Utah, reportedly introduced the concept of grooving centerlines in an attempt to provide a rumble effect for alerting drivers straying outside their traffic lanes. It was later observed that the painted grooves were more visible at night during wet weather than were normal paint stripes. The concept of grooving and painting centerlines was thus promoted, and, as a result, several test sections were placed on Nebraska highways in the summer of 1968. In order to evaluate the effectiveness of grooving the centerline prior to striping, a section uf newly constructed pavement of I 71 in Carroll County, Kentucky, was chosen for an experimental installation. This interim report covers installation of the grooves and a preliminary evaluation of their value to date

    Blockchain Storage – Drive Configurations and Performance Analysis

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    This project will analyze the results of trials implementing various storage methods on Geth nodes to synchronize and maintain a full-archive state of the Ethereum blockchain. The purpose of these trials is to gain deeper insight to the process of lowering cost and increasing efficiency of blockchain storage using available technologies, analyzing results of various storage drives under similar conditions. It provides performance analysis and describes performance of each trial in relation to the others

    Using NDF and ADF to balance diets (1990)

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    In University of Missouri Agricultural guides G3150 and G3160 we explained how detergent solutions are used to measure forage fiber. The guides show how neutral detergent solution can be used to measure neutral detergent fiber (NDF). NDF represents the total plant fiber or cell wall including hemicellulose, cellulose and lignin. These guides also show how acid detergent solution can be used to measure acid detergent fiber (ADF), which contains cellulose and lignin. Both ADF and NDF data help to more accurately estimate feed intake, energy values and animal performanceNew7/90f7M

    Progress Toward National Estimates of Police Use of Force

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    This research builds on three decades of effort to produce national estimates of the amount and rate of force used by law enforcement officers in the United States. Prior efforts to produce national estimates have suffered from poor and inconsistent measurements of force, small and unrepresentative samples, low survey and/or item response rates, and disparate reporting of rates of force. The present study employs data from a nationally representative survey of state and local law enforcement agencies that has a high survey response rate as well as a relatively high rate of reporting uses of force. Using data on arrests for violent offenses and the number of sworn officers to impute missing data on uses of force, we estimate a total of 337,590 use of physical force incidents among State and local law enforcement agencies during 2012 with a 95 percent confidence interval of +/- 10,470 incidents or +/- 3.1 percent. This article reports the extent to which the number and rate of force incidents vary by the type and size of law enforcement agencies. Our findings demonstrate the willingness of a large proportion of law enforcement agencies to voluntarily report the amount of force used by their officers and the relative strengths and weaknesses of the Law Enforcement Management and Administrative Statistics (LEMAS) program to produce nationally representative information about police behavior

    Progress toward national estimates of police use of force

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    This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This research builds on three decades of effort to produce national estimates of the amount and rate of force used by law enforcement officers in the United States. Prior efforts to produce national estimates have suffered from poor and inconsistent measurements of force, small and unrepresentative samples, low survey and/or item response rates, and disparate reporting of rates of force. The present study employs data from a nationally representative survey of state and local law enforcement agencies that has a high survey response rate as well as a relatively high rate of reporting uses of force. Using data on arrests for violent offenses and the number of sworn officers to impute missing data on uses of force, we estimate a total of 337,590 use of physical force incidents among State and local law enforcement agencies during 2012 with a 95 percent confidence interval of +/- 10,470 incidents or +/- 3.1 percent. This article reports the extent to which the number and rate of force incidents vary by the type and size of law enforcement agencies. Our findings demonstrate the willingness of a large proportion of law enforcement agencies to voluntarily report the amount of force used by their officers and the relative strengths and weaknesses of the Law Enforcement Management and Administrative Statistics (LEMAS) program to produce nationally representative information about police behavior

    Cold Atmospheric Pressure Plasmas for Food Applications

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    Successfully distributing shelf food requires treatment to eliminate microorganisms. Current chemical methods, such as chlorine wash, can alter food quality while only being effective for a limited time. Cold atmospheric pressure plasmas (CAPs) can eradicate the microorganisms responsible for food spoilage and foodborne illness. Optimizing CAP treatments requires understanding the reactive species generated and relating them to eradication efficiency. Recent studies have used optical emission spectroscopy (OES) to determine the species generated in a sealed package that would hold food. In this study,we supplement the OES results with optical absorption spectroscopy (OAS) using the same gases (helium, nitrogen, compressed air, humid air) to elucidate plasma chemistry and temperature. We first reproduce previous results using a new setup while assessing the impact of the package and surrounding box on the plasma spectrum. A UV-Vis light lightsource is emitted through a series of lenses placed next to the plasma. Analysis using SpecAir software allows the identification of absorbed peaks and the calculation of rotational, vibrational, and electron temperatures. Results show that the air plasma produces a primary absorbance peak at a wavelength of ~260 nm, demonstrating the diagnostic capability of this technique . Species generation declined dramatically during the first two minutes of treatment with the effect leveling off thereafter. These findings elucidate reactive species generation within the plasma to optimize CAP systems for microorganism decontamination

    Using NDF and ADF to balance diets (1993)

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    This publication shows how neutral detergent solution can be used to measure neutral detergent fiber (NDF). NDF represents the total plant fiber or cell wall including hemicellulose, cellulose and lignin. This publication also shows how acid detergent solution can be used to measure acid detergent fiber (ADF), which contains cellulose and lignin. Both ADF and NDF data help to more accurately estimate feed intake, energy values and animal performance

    Incorporating spatial dependence into a multicellular tumor spheroid growth model

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    Recent models for organism and tumor growth yield simple scaling laws based on conservation of energy. Here, we extend such a model to include spatial dependence to model necrotic core formation. We adopt the allometric equation for tumor volume with a reaction-diffusion equation for nutrient concentration. In addition, we assume that the total metabolic energy and average cellular metabolic rate depend on nutrient concentration in a Michaelis-Menten-like manner. From experimental results, we relate the necrotic volume to nutrient consumption and estimate both the time and nutrient concentration at necrotic core formation. Based on experimental results, we demand that the necrotic core radius varies linearly with tumor radius after core formation and extend the equations for tumor volume and nutrient concentration to the postnecrotic core regime. In particular, we obtain excellent agreement with experimental data and the final steady-state viable rim thickness.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87333/2/124701_1.pd
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