677 research outputs found

    Land Grant Application- Patten, James (Bolton)

    Get PDF
    Land grant application submitted to the Maine Land Office for James Patten for service in the Revolutionary War.https://digitalmaine.com/revolutionary_war_mass/1262/thumbnail.jp

    Practical applications of small-angle neutron scattering.

    Get PDF
    Recent improvements in beam-line accessibility and technology have led to small-angle neutron scattering (SANS) becoming more frequently applied to materials problems. SANS has been used to study the assembly, dispersion, alignment and mixing of nanoscale condensed matter, as well as to characterise the internal structure of organic thin films, porous structures and inclusions within steel. Using time-resolved SANS, growth mechanisms in materials systems and soft matter phase transitions can also be explored. This review is intended for newcomers to SANS as well as experts. Therefore, the basic knowledge required for its use is first summarised. After this introduction, various examples are given of the types of soft and hard matter that have been studied by SANS. The information that can be extracted from the data is highlighted, alongside the methods used to obtain it. In addition to presenting the findings, explanations are provided on how the SANS measurements were optimised, such as the use of contrast variation to highlight specific parts of a structure. Emphasis is placed on the use of complementary techniques to improve data quality (e.g. using other scattering methods) and the accuracy of data analysis (e.g. using microscopy to separately determine shape and size). This is done with a view to providing guidance on how best to design and analyse future SANS measurements on materials not listed below

    SPATIAL ECOLOGY AND HABITAT USE OF THE WESTERN MASSASAUGA (SISTRURUS TERGEMINUS) IN NEBRASKA

    Get PDF
    We used radiotelemetry during 2004 and 2005 to investigate seasonal movements and habitat use and to improve our understanding of how land management practices were affecting Western Massasauga (Sistrurus tergeminus) populations in Nebraska. We found Western Massasaugas to brumate in crayfish burrows 100% of the time, and spring emergence occurred during March - April. The longest movements occurred during May when snakes were moving away from brumation sites to summer habitat, after which movements decreased until a second peak in August. We did not find significant differences between male and female activity area, range length, total distance moved, daily movement, or distance from spring and fall brumation sites. However the core activity range of females was significantly less than that of males. During the active season, grassland habitat was used 75.6% of the time compared to habitats of grassland-shrubs (10.7%), hydrophilic vegetation (9.1%), woodlands (3.1%), and shrublands (1.5%). Identifying variations in a species spatial ecology is important for achieving long-term conservation goals because life history events, resource availability, and land management practices may have an effect on seasonal movements and habitat use. The results of our study demonstrate the need for, and some of the necessary data for, improved land management planning in order to meet conservation needs of the Western Massasauga in Nebraska

    On-line data archives

    Get PDF
    ©2001 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.Digital libraries and other large archives of electronically retrievable and manipulable material are becoming widespread in both commercial and scientific arenas. Advances in networking technologies have led to a greater proliferation of wide-area distributed data warehousing with associated data management challenges. We review tools and technologies for supporting distributed on-line data archives and explain our key concept of active data archives, in which data can be, processed on-demand before delivery. We are developing wide-area data warehousing software infrastructure for geographically distributed archives of large scientific data sets, such as satellite image data, that are stored hierarchically on disk arrays and tape silos and are accessed by a variety of scientific and decision support applications. Interoperability is a major issue for distributed data archives and requires standards for server interfaces and metadata. We review present activities and our contributions in developing such standards for different application areas.K. Hawick, P. Coddington, H. James, C. Patte

    Wireless object tracking platform for tangible user interfaces

    Get PDF
    Thesis (S.M.)--Massachusetts Institute of Technology, Program in Media Arts & Sciences, 2001.Includes bibliographical references (p. 107-110).Sensetable is a system that electromagnetically tracks the positions and orientations of multiple wireless objects on a tabletop display surface. The system offers two types of improvements over existing tracking approaches such as computer vision. First, the system tracks objects quickly and accurately without susceptibility to occlusion or changes in lighting conditions. Second, the tracked objects have state that can be modified by attaching physical dials and modifiers. The system can detect these changes in real-time. I present several new interaction techniques developed in the context of this system. Finally, I present several applications of the system, the most thoroughly developed of which is system dynamics simulation.by James McMichael Patten.S.M

    Mechanical constraints as common ground between people and computers

    Get PDF
    Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2006.Includes bibliographical references (p. 143-149).This thesis presents a new type of human-computer interface based on mechanical constraints that combines some of the tactile feedback and affordances of mechanical systems with the abstract computational power of modern computers. The interface is based on a tabletop interaction surface that can sense and move small objects on top of it. Computation is merged with dynamic physical processes on the tabletop that are exposed to and modified by the user in order to accomplish his or her task. The system places mechanical constraints and mathematical constraints on the same level, allowing users to guide simulations and optimization processes by constraining the motion of physical objects on the interaction surface. The interface provides ample opportunities for improvisation by allowing the user to employ a rich variety of everyday physical objects as interface elements. Subjects in an evaluation were more effective at solving a complex spatial layout problem using this system than with either of two alternative interfaces that did not feature actuation.James McMichael Patten.Ph.D

    Gastrointestinal nematode control practices on lowland sheep farms in Ireland with reference to selection for anthelmintic resistance

    Get PDF
    Gastrointestinal parasitism is a widely recognised problem in sheep production, particularly for lambs. While anthelmintics have a pivotal role in controlling the effects of parasites, there is a paucity of data on how farmers use anthelmintics. A representative sample of Irish lowland farmers were surveyed regarding their parasite control practices and risk factors that may contribute to the development of anthelmintic resistance. Questionnaires were distributed to 166 lowland Irish sheep producers. The vast majority of respondents treated their sheep with anthelmintics. Lambs were the cohort treated most frequently, the majority of farmers followed a set programme as opposed to treating at sign of disease. A substantial proportion (61%) administered four or more treatments to lambs in a 'normal' year. Departures from best practice in anthelmintic administration that would encourage the development of anthelmintic resistance were observed. In conclusion, in the light of anthelmintic resistance, there is a need for a greater awareness of the principles that underpin the sustainable use of anthelmintics and practices that preserve anthelmintic efficacy should be given a very high priority in the design of helminth control programmes on each farm. To this end, given that veterinary practitioners and agricultural advisors were considered to be the farmer's most popular information resource, the capacity of these professions to communicate information relating to best practice in parasite control should be targeted

    Construction by Replacement: A new approach to simulation modeling

    Get PDF
    Simulation modeling can be valuable in many areas of management science, but it is often costly, time-consuming, and difficult to do. To reduce these problems, system dynamics researchers have previously developed standard pieces of model structure, called molecules, that can be reused in different models. However, the models assembled from these molecules often lacked feedback loops and generated few, if any, insights. This paper describes a new and more promising approach to using molecules in system dynamics modeling. The heart of the approach is a systematically organized library (or taxonomy) of predefined model components, or molecules, and a set of software tools for replacing one molecule with another. Users start with a simple generic model and progressively replace parts of the model with more specialized molecules from a systematically organized library of predefined components. These substitutions either create a new running model automatically or request further manual changes from the user. The paper describes our exploration using this approach to construct system dynamics models of supply chain processes in a large manufacturing company. The experiment included developing an innovative “tangible user interface” and a comprehensive catalog of system dynamics molecules. The paper concludes with a discussion of the benefits and limitations of this approach

    Graphical programming: A systems approach for telerobotic servicing of space assets

    Get PDF
    Satellite servicing is in many ways analogous to subsea robotic servicing in the late 1970's. A cost effective, reliable, telerobotic capability had to be demonstrated before the oil companies invested money in deep water robot serviceable production facilities. In the same sense, aeronautic engineers will not design satellites for telerobotic servicing until such a quantifiable capability has been demonstrated. New space servicing systems will be markedly different than existing space robot systems. Past space manipulator systems, including the Space Shuttle's robot arm, have used master/slave technologies with poor fidelity, slow operating speeds and most importantly, in-orbit human operators. In contrast, new systems will be capable of precision operations, conducted at higher rates of speed, and be commanded via ground-control communication links. Challenge presented by this environment include achieving a mandated level of robustness and dependability, radiation hardening, minimum weight and power consumption, and a system which accommodates the inherent communication delay between the ground station and the satellite. There is also a need for a user interface which is easy to use, ensures collision free motions, and is capable of adjusting to an unknown workcell (for repair operations the condition of the satellite may not be known in advance). This paper describes the novel technologies required to deliver such a capability

    On the dispersion in lithium and potassium among late-type stars in young clusters: IC 2602

    Get PDF
    We have measured the equivalent width (EW) of the K I 7699 A line in a sample of G and K-type members of the ~35 Myr old cluster IC 2602 for which a dispersion in Li EWs had been reported by previous studies. Active cluster stars with 0.75 < (B-V)o < 1 are characterized by a dispersion in the EW of the K I 7699 A, while earlier and later-type stars do not show any significant scatter. Cluster stars at all colors show potassium EW excesses with respect to field inactive stars; furthermore, a statistically significant relationship is found between differential potassium EWs and log Lx/Lbol ratios, indicating that the EWs of the potassium feature are altered by activity. Our results suggest that the dispersion in Li EWs observed among cluster stars later than (B-V)o ~ 1 cannot be fully explained by the effects of activity. No final conclusion can instead be drawn for earlier-type stars.Comment: accepted by A&
    • …
    corecore