The neutron method for measuring soil moisture content - a review

THE various methods of measuring the soil moisture content and its variations in space and time have been reviewed by many authors (Taylor, 1955; Marshall, 1959; Todd, 1960; Ballard and Gardner, 1965; Cope and Trickett, 1965). The moisture content is either measured directly, as in the gravimetric method, or it is estimated by determining its relationship to some other property of the soil as in the electric resistance, tensiometer and neutron scattering methods. The neutron scattering method estimates the moisture content of the soil by measurement of its hydrogen content. This paper summarizes the theoretical and practical aspects of the method and provides a bibliography which includes references to papers published more recently than those provided by Sweeny (1962), Ballard and Gardner (1965), and the Commonwealth Bureau of Soils (1968)

Competing in the RoboCup Rescue Robot League

RoboCup Rescue is an international competition in which robots compete to find disaster victims in a simulated earthquake environment. It features both a Rescue Simulation League (RSL) which is entirely computer simulated, and a Rescue Robot League (RRL) with real robots and a test arena. This paper will describe the experience gained sending an undergraduate team to compete in the Rescue Robot League at the RoboCup German Open in 2008 and 2009. The design of the test arena and the rules of the competition will be outlined; as will the approaches taken by different teams; and the competition results

An intelligent tutoring system for the investigation of high performance skill acquisition

The issue of training high performance skills is of increasing concern. These skills include tasks such as driving a car, playing the piano, and flying an aircraft. Traditionally, the training of high performance skills has been accomplished through the use of expensive, high-fidelity, 3-D simulators, and/or on-the-job training using the actual equipment. Such an approach to training is quite expensive. The design, implementation, and deployment of an intelligent tutoring system developed for the purpose of studying the effectiveness of skill acquisition using lower-cost, lower-physical-fidelity, 2-D simulation. Preliminary experimental results are quite encouraging, indicating that intelligent tutoring systems are a cost-effective means of training high performance skills

Ambiguity resolution of single frequency GPS measurements

This thesis considers the design of an autonomous ride-on lawnmower, with particular attention paid to the problem of single frequency Global Navigation Satellite System (GNSS) ambiguity resolution. An overall design is proposed for the modification of an existing ride-on lawnmower for autonomous operation. Ways of sensing obstacles and the vehicle's position are compared. The system's computer-to-vehicle interface, software architecture, path planning and control algorithms are all described. An overview of satellite navigation systems is presented, and it is shown that existing high precision single frequency GNSS receivers often require time-consuming initialisation periods to perform ambiguity resolution. The impact of prior knowledge of the topography is analysed. A new algorithm is proposed, to deal with the situation where different areas of the map have been mapped at different levels of precision. Stationary and kinematic tests with real-world data demonstrate that when the map is sufficiently precise, substantial improvements in initialisation time are possible. Another algorithm is proposed, using a noise-detecting acceptance test taking data from multiple receivers on the same vehicle (a GNSS com- pass configuration). This allows a more demanding threshold to be used when noise levels are high, and a less demanding threshold to be used at other times. Tests of this algorithm reveal only slight performance improvements. A final algorithm is proposed, using Monte Carlo simulation to account for time-correlated noise during ambiguity resolution. The method allows a fixed failure rate configuration with variable time, meaning no ambiguities are left floating. Substantial improvements in initialisation time are demonstrated. The overall performance of the integrated system is summarised, conclusions are drawn, further work is proposed, and limitations of the techniques and tests performed are identified

Confinement contains condensates

Dynamical chiral symmetry breaking and its connection with the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that were commonly viewed as constant empirical mass-scales that fill all spacetime, are instead wholly contained within hadrons; viz., they are a property of hadrons themselves and expressed, e.g., in their Bethe-Salpeter or light-front wave functions. We explain that this paradigm is consistent with empirical evidence, and incidentally expose misconceptions in a recent Comment.Comment: 10 pages, 2 figure

Facilitating Wiki/Repository Communication with Metadata

4th International Conference on Open RepositoriesThis presentation was part of the session : Fedora User Group PresentationsDate: 2009-05-20 01:30 PM – 03:00 PMThe National Science Digital Library (NSDL) Materials Digital Library Pathway (MatDL) has implemented an information infrastructure to disseminate government funded research results and to provide content as well as services to support the integration of research and education in materials. This paper describes how we are enabling two-way communication between a digital repository and open-source collaborative tools, such as wikis, to support users in materials research and education in the creation and re-use of compelling learning resources. A search results plug-in for MediaWiki has been developed to display relevant search results from the Fedora-based MatDL repository in the Soft Matter Wiki established and developed by MatDL and its partners. Wiki-to-repository information transfer has also been facilitated by mapping the metadata associated with resources originating in the wiki onto Dublin Core (DC) metadata elements and making the metadata and resources available in the repository.The Materials Digital Library Pathway (DUE-0532831) is supported by the National Science Foundation

Quark-gluon vertex model and lattice-QCD data

A model for the dressed quark-gluon vertex, at zero gluon momentum, is formed from a nonperturbative extension of the two Feynman diagrams that contribute at 1-loop in perturbation theory. The required input is an existing ladder-rainbow model Bethe-Salpeter kernel from an approach based on the Dyson-Schwinger equations; no new parameters are introduced. The model includes an Ansatz for the triple-gluon vertex. Two of the three vertex amplitudes from the model provide a point-wise description of the recent quenched lattice-QCD data. An estimate of the effects of quenching is made.Comment: 4 pages, 3 figure

Cloud Computing dan Dampaknya terhadap Bisnis

The purpose of this paper is to provide an overview of cloud computing and its development as well as the advantages and disadvantages of cloud computing implementation at some companies. Some literature studies from journals, textbooks and internet sources are discussed. Based on these searches it is known that the cloud computing as a technology that utilizes internet services uses a central server to the virtual nature of data and application maintenance purposes. The existence of Cloud Computing itself causes a change in the way thetechnology information system works at an company. Security and data storage systems have become important factors for the company.Cloud Computing technology provides a great advantage for most enterprises