230 research outputs found
The Price of Freedom: Slavery and Manumission in Baltimore and Early National Maryland
A stereotypical image of manumission is that of a benign plantation owner freeing his slaves on his deathbed. But as Stephen Whitman demonstrates, the truth was far more complex, especially in border states where manumission was much more common.
Whitman analyzes the economic and social history of Baltimore to show how the vigorous growth of the city required the exploitation of rural slaves. To prevent them from escaping and to spur higher production, owners entered into arrangements with their slaves, promising eventual freedom in return for many years\u27 hard work. The Price of Freedom reveals how blacks played a critical role in freeing themselves from slavery. Yet it was an imperfect victory. Once Baltimore\u27s economic growth began to slow, freed blacks were virtually excluded from craft apprenticeships, and European immigrants supplanted them as a trained labor force.https://uknowledge.uky.edu/upk_african_american_studies/1018/thumbnail.jp
IPC2012-90284 GUIDANCE ON IN LINE INSPECTION FIRST RUN SUCCESS
ABSTRACT First run success is a key performance measure used in the BP Global In Line Inspection (ILI) Contract Three definitions have been established for run success: Technical; Commercial and Operational. Each has a place although it is Operational run success that drives improvements between operators and suppliers. The introduction of a performance measure for first run success increases the focus on getting things right the first time. The financial cost of ILI run failure has probably been underestimated by the industry; although it is estimated that it could be as high as 30% of total contracted costs for ILI. For some projects the costs associated with a failed run can be far greater than the original project costs (e.g. additional vessel support costs for deployment or recovery during offshore operations). A failed run can also result in a delayed inspection and an associated increased risk as well as potentially compromising compliance with regulatory requirements. The consequences of run failure vary in severity and can be presented in a pyramid similar to the typical representation of safety statistics. A stuck tool requiring intervention or a pipeline failure, as a result of an incorrect inspection report, would be at the top of the pyramid. The lower tiers would capture technical failures and the effectiveness of cleaning. Understanding the consequence of failures can help drive performance improvements across the industry. As part of the BP continuous improvement process, ILI Suppliers and internal stakeholders were brought together for a facilitated workshop to understand the factors affecting first run success rates. The workshop identified a number of common themes which were consistent across all of the Suppliers addressing; both operational issues and tool performance. A Guidance Note was then developed with the ILI Suppliers to drive improvements in first run success rates. This was shared with the Pipeline Operators Forum (POF) in October 2011 and has been further developed as a POF Guidance Document. A separate guidance note has been developed to address recommended practices for collecting and verifying field data. Successful ILI requires good communication between all parties. As the industry starts to inspect more difficult and challenging lines it will be important to improve ILI run success rates. Across the industry we probably know how to do it, but doing it consistently is the challenge. The development of industry Guidance Notes represent a small step towards achieving this objective. As ILI operations improve the focus will increasingly turn to the reliability of tools. There is much that can be learnt from other industry sectors, such as the motor or aviation industry, on improving reliability of components and systems. This will require an increased use of preventative maintenance practices. There is also a need to create a common basis for reporting reliability of inspection tools and for this to be taken into account when operators make their selection of ILI tools. The Global ILI Contract has brought an increased focus to the performance of the overall inspection process which is driving improvements in first run success rates. It has facilitated the development of guidelines on best practice and is starting to set standards for reliability. The high level of cooperation between suppliers and operators to drive improvements in this area is a measure of the importance of first run success rates to all parts of our industry. Achieving ILI first run success requires both the operator and ILI supplier to work together. Whilst each has a key part to play effective communication from an early stage is essential
Countermovement Jump Performance Changes over the Course of Collegiate Basketball Pre-Season Associated with Block Periodization Model of Strength and Conditioning Program
Modelling the emergent dynamics and major metabolites of the human colonic microbiota
Funded by Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS) Acknowledgements We would like to thank Thanasis Vogogias, David Nutter and Alec Mann for their assistance in developing the software for this model. We also acknowledge the Scottish Government’s Rural and Environment Science and Analytical Services Division (RESAS) for their financial support. Furthermore,many thanks go to the two anonymous reviewers whose hard work has greatly improved this paper.Peer reviewedPublisher PD
Rapid Display of Radiographic Images
The requirements for the rapid display of radiographic images exceed the capabilities of widely available display, computer and communication technologies. Computed radiography captures data with a resolution of about four megapixels. Large format displays are available that can present over four megapixels. One megapixel displays are practical for use in combination with large format displays and in areas where the viewing task does not require primary diagnosis. This paper describes an electronic radiology system that approximates the highest quality systems, but through the use of several interesting techniques allows the possibility of its widespread installation throughout hospitals. The techniques uses can be grouped under three major systems concepts: a local, high-speed Image Server, one of more physician\u27s workstations each with one or more high-performance Auxiliary Displays specialized to the radiology viewing task, and dedicated, high-speed communication links between the server and the displays. This approach is enhanced by the use of a progressive transmission scheme to decrease the latency for viewing four megapixel images. The system includes an Image Server with storage for over 600 4 megapixel images and high-speed link. A subsampled megapixel image is fetched from disk and transmitted to the display in about one second followed by the full resolution 4 megapixel in about 2.5 seconds. Other system components include a megapixel display with a 6 megapixel display memory space and frame-rate update of image roam, zoom and contrast. Plans for clinical use are presented
JWST's Cryogenic Position Metrology System
The James Webb Space Telescope will undergo a full system test in the cryogenic vacuum chamber A at the Johnson Spaceflight Center in order to verify the overall performance of the combined telescope and instrument suite. This will be the largest and most extensive cryogenic test ever undertaken. Early in the test system development, it was determined that precise position measurements of the overall hardware would enhance the test results. Various concepts were considered before selecting photogrammetry for this metrology. Photogrammetry has been used in space systems for decades, however cryogenic use combined with the size and the optical/thermal sensitivity of JWST creates a unique set of implementation challenges. This paper provides an overview of the JWST photogrammetric system and mitigation strategies for three key engineering design challenges: 1) the thermal design of the viewing windows to prevent excessive heat leak and stray light to the test article 2) cost effective motors and mechanisms to provide the angle diversity required, and 3) camera-flash life and reliability sufficient for inaccessible use during the number and duration of the cryogenic tests
Autonomous Microbial Sampler (AMS), a device for the uncontaminated collection of multiple microbial samples from submarine hydrothermal vents and other aquatic environments
Author Posting. © Elsevier B.V., 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 53 (2006): 894-916, doi:10.1016/j.dsr.2006.01.009.An Autonomous Microbial Sampler (AMS) is described that will obtain uncontaminated and
exogenous DNA-free microbial samples from most marine, fresh water and hydrothermal
ecosystems. Sampling with the AMS may be conducted using manned submersibles, Remotely
Operated Vehicles (ROVs), Autonomous Underwater Vehicles (AUVs), or when tethered to a
hydrowire during hydrocast operations on research vessels. The modular device consists of a
titanium nozzle for sampling in potentially hot environments (>350°C) and fluid-handling
components for the collection of six independent filtered or unfiltered samples. An onboard
microcomputer permits sampling to be controlled by the investigator, by external devices (e.g.,
AUV computer), or by internal programming. Temperature, volume pumped and other
parameters are recorded during sampling. Complete protection of samples from microbial
contamination was observed in tests simulating deployment of the AMS in coastal seawater,
where the sampling nozzle was exposed to seawater containing 1x106 cells ml-1 of a red
pigmented tracer organism, Serratia marinorubra. Field testing of the AMS at a hydrothermal
vent field was successfully undertaken in 2000. Results of DNA destruction studies have
revealed that exposure of samples of the Eukaryote Euglena and the bacterium S. marinorubra to
0.5 N sulfuric acid at 23°C for 1 hour was sufficient to remove Polymerase Chain Reaction
(PCR) amplifiable DNA. Studies assessing the suitability of hydrogen peroxide as a sterilizing
and DNA-destroying agent showed that 20 or 30% hydrogen peroxide sterilized samples of
Serratia in 1 hr and destroyed the DNA of Serratia, in 3 hrs, but not 1 or 2 hrs. DNA AWAY™
killed Serratia and destroyed the DNA of both Serratia and the vent microbe (GB-D) of the
genus Pyrococcus in 1 hour.This work was supported by a DOC/NOAA Small Business Innovative Research Award,
Contract No. 50-DKNA-9-90116 awarded to McLane Research Laboratories, Inc. and (via
subcontract) to the Woods Hole Oceanographic Institution. Some of the microbial testing work
was also supported by the National Science Foundation, Grant No. IBN-0131557 and the Woods
Hole Oceanographic Inst. Deep Ocean Exploration Institute Grant No. 25051131
Toward a Temporal Theory of Language
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67931/2/10.1177_007542429702500404.pd
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