5,938 research outputs found

    Hydrological connectivity of soil pipes determined by ground-penetrating radar tracer detection

    Get PDF
    Soil pipes are common and important features of many catchments, particularly in semi-arid and humid areas, and can contribute a large proportion of runoff to river systems. They may also significantly influence catchment sediment and solute yield. However, there are often problems in finding and defining soil pipe networks which are located deep below the surface. Ground penetrating radar (GPR) has been used for non-destructive identification and mapping of soil pipes in blanket peat catchments. While GPR can identify subsurface cavities, it cannot alone determine hydrological connectivity between one cavity and another. This paper presents results from an experiment to test the ability of GPR to establish hydrological connectivity between pipes through use of a tracer solution. Sodium chloride was injected into pipe cavities previously detected by the radar. The GPR was placed downslope of the injection points and positioned on the ground directly above detected soil pipes. The resultant radargrams showed significant changes in reflectance from some cavities and no change from others. Pipe waters were sampled in order to check the radar results. Changes in electrical conductivity of the pipe water could be detected by the GPR, without data post-processing, when background levels were increased by greater than approximately twofold. It was thus possible to rapidly determine hydrological connectivity of soil pipes within dense pipe networks across hillslopes without ground disturbance. It was also possible to remotely measure travel times through pipe systems; the passing of the salt wave below the GPR produced an easily detectable signal on the radargram which required no post-processing. The technique should allow remote sensing of water sources and sinks for soil pipes below the surface. The improved understanding of flowpath connectivity will be important for understanding water delivery, solutional and particulate denudation, and hydrological and geomorphological model development

    Altruism among relatives and non-relatives

    Get PDF
    The amount of their own monetary reward that undergraduate participants claimed they were willing to forgo, in order to give $75 to another person, decreased hyperbolically as social distance increased between the participant and the other person. Relatives tended to be ranked at closer social distances than were non-relatives. However, even at the same social distance, participants were willing to forgo significantly more money for the benefit of relatives than for the benefit of non-relatives. These results imply that altruism is determined by factors in addition to social distance

    An investigation of key growth industry sectors in Wales using Multi-Sectoral Qualitative Analysis

    Get PDF
    This paper examines the problem of key sector identification in regional economies. Whilst the paper questions the desirability of policy focusing on the promotion of key sectors, it suggests that tools are generally underdeveloped to identify these sectors. The paper suggests that multi-sectoral qualitative analysis provides one means of forming conclusions on sector potentials.

    Tattooing Is Not A Crime

    Get PDF

    Political Love (Just A Name)

    Get PDF

    That\u27s Pretty Much Everyone

    Get PDF

    Identifying Real Cost Saving in Lean Manufacturing

    Get PDF
    Lean manufacturing is well-known as an effective means toward cost savings, but to convince management to support a culture shift to implement a lean manufacturing program there must be confidence in understanding what real effective and measurable lean savings are. This case study analyzes data from one specific lean event and points out areas of deficiency and shows how misreporting cost savings can hurt the lean program and the creditability of the lean practitioners. Often, lean practitioners are so anxious to show what benefit their lean projects have attained, they cite everything they can think of to justify their lean project, some of which can be questionable cost savings and can negatively impact the long term credibility of the lean program. This case study from Boeing’s Ground-Based Missile Defense (GMD) program will evaluate and confirm what constitutes real cost savings as a result of a continuous improvement project to reduce the cycle time of interceptor integration. This evaluation includes professional perceptions of lean cost savings as part of the conclusion of what constitutes real cost savings in a lean program. This case study evaluates one particular event of many events done by companies every day. Another area of research could focus on instances of lean programs not capturing and reporting all the effective cost savings from a lean project which can have some of the same negative effects as reporting more costs saving than are truly being realized as this study addresses

    A Markov Switching Model of Congressional Partisan Regimes

    Get PDF
    Studies of development and change in partisan fortunes in the US emphasize epochs of partisan stability, separated by critical events or turning points. A major empirical issue that has plagued the study of American political development is the estimation of the critical moments and durations of these partisan regimes. In this paper we introduce a fresh approach to the study of partisan regimes. Our method is based in the method of Markov switching, introduced by James Hamilton. We apply Hamilton’s approach to the size of party coalitions in the US House of Representatives from 1854 to the present. Our model assumes that the political system is either in a state of domination by one party or it is not (in which case the other party dominates). The Markov switching approach also yields estimated state probabilities that allow us to make inferences about periods of empirical party balance. Roughly speaking, when the Republicans constitute the dominant partisan coalition, they can expect to capture 60 percent of House seats in any given election. The Democrats can expect 59 percent when dominant. Our method also allows the estimation of critical transition points between Republican and Democratic partisan coalitions. The periods we identify as governed by a being Republican coalition are roughly 1860 through 1872, 1894 through 1906, and 1918 through 1928.

    Citation and peer review of data: moving towards formal data publication

    Get PDF
    This paper discusses many of the issues associated with formally publishing data in academia, focusing primarily on the structures that need to be put in place for peer review and formal citation of datasets. Data publication is becoming increasingly important to the scientific community, as it will provide a mechanism for those who create data to receive academic credit for their work and will allow the conclusions arising from an analysis to be more readily verifiable, thus promoting transparency in the scientific process. Peer review of data will also provide a mechanism for ensuring the quality of datasets, and we provide suggestions on the types of activities one expects to see in the peer review of data. A simple taxonomy of data publication methodologies is presented and evaluated, and the paper concludes with a discussion of dataset granularity, transience and semantics, along with a recommended human-readable citation syntax

    PhD

    Get PDF
    dissertationThe mammalian retina is comprised of 55-60 cell types mediating transduction of photic information through visual preprocessing channels. These cell types fall into six major cell superclasses including photoreceptors, horizontal, amacrine, Muller and ganglion cells. Through computational molecular phenotyping, using amino acids as discriminands, this dissertation shows that the major cellular superclasses of the murine retina are subdivisible into the following natural classes; 1 retinal pigment epithelium class, 2 photoreceptor, 2 bipolar cell, 1 horizontal cell, 15 amacrine cell, 1 Muller cell, and 7 ganglion cell classes. Retinal degenerative diseases like retinitis pigmentosa result in loss of photoreceptors, which constitutes deafferentation of the neural retina. This deafferentation, when complete, is followed by retinal remodeling, which is the common fate of all retinal degenerations that trigger photoreceptor loss. The same strategy used to visualize cell classes in wild type murine retina was applied to examples of retinal degenerative disease in human tissues and naturally and genetically engineered models, examining all cell types in 17 human cases of retinitis pigmentosa (RP) and 85 cases of rodent retinal degenerations encompassing 13 different genetic models. Computational molecular phenotyping concurrently visualized glial transformations, neuronal translocations, and the emergence of novel synaptic complexes, achievements not possible with any other method. The fusion of phenotyping and anatomy at the ultrastructure level also enabled the modeling of synaptic connections, illustrating that the degenerating retina produces new synapses with vigor with the possibility that this phenomenon might be exploited to rescue vision. However, this circuitry is likely corruptive of visual processing and reflects, we believe, attempts by neurons to find synaptic excitation, demonstrating that even minor rewiring seriously corrupts signal processing in retinal pathways leaving many current approaches to bionic and biological retinal rescue unsustainable. The ultimate conclusion is that the sequelae of retinal degenerative disease are far more complex than previously believed, and schemes to rescue vision via bionic implants or stem/engineered cells are based on presumed beliefs in preservation of normal wiring and cell population patterning after photoreceptor death. Those beliefs are incorrect: retinal neurons die, migrate, and create new circuitries. Vision rescue strategies will need to be refined
    • …
    corecore