Isometric Representations of Totally Ordered Semigroups

Let S be a subsemigroup of an abelian torsion-free group G. If S is a positive cone of G, then all C*-algebras generated by faithful isometrical non-unitary representations of S are canonically isomorphic. Proved by Murphy, this statement generalized the well-known theorems of Coburn and Douglas. In this note we prove the reverse. If all C*-algebras generated by faithful isometrical non-unitary representations of S are canonically isomorphic, then S is a positive cone of G. Also we consider G = Z\times Z and prove that if S induces total order on G, then there exist at least two unitarily not equivalent irreducible isometrical representation of S. And if the order is lexicographical-product order, then all such representations are unitarily equivalent.Comment: February 21, 2012. Kazan, Russi

Li Diffusion and High-Voltage Cycling Behavior of Thin-Film LiCoO2 Cathodes

Mass transport and thermodynamic properties of Li{sub x}CoO{sub 2} were studied by the potentiostatic intermittent titration technique (PITT) using solid-state thin-film batteries that provide a well-defined diffusion geometry. Both the chemical diffusion coefficient and the thermodynamic factor have minima at the phase boundaries of the Li/vacancy ordered phase ''Li{sub 0.5}CoO{sub 2}''. The self-diffusion coefficient of Li has a minimum at x = 0.5 associated with the Li/vacancy ordering. As the degree of ordering increases, the nonmonotonic variations become more pronounced when approaching x = 0.5 in Li{sub x}CoO{sub 2}. We also show that thin-film LiCoO{sub 2} cathodes having grains of sub-micrometer size combined with the Li upon electrolyte exhibit excellent capacity retention when charged up to 4.5 V

Development of Auto Scaling Method for 3D Rock Fragmentation Measurement System

Fragmentation Distribution is one of the important aspects of mining operations as it affects productivities on the majority of Mine-to-Mill operations. Nevertheless the significance of fragmentation management, the mining industry has relied on 2D image based fragmentation measurement system which poses many downsides. To overcome the drawbacks of current 2D fragmentation measurement system, 3D Rock Fragmentation Measurement System has been proposed with using 3D photogrammetry technologies. One of the common difficulty of fragmentation measurement system is scaling of the object, which is an essential component to secure the accuracy of particle size distribution. In this study, the actual scales and size information of objects have been obtained by measuring the acceleration when moving between the photographing points and giving the information of the distance obtained from the acceleration. The developed system would be equipped with the 3D Rock Fragmentation Measurement System

Development of a Remote Rock Fragmentation Size Distribution Measurement System for Surface Mines Using 3D Photogrammetry

One of the factors that can affect the efficiency of a mining operation is the fragmentation size distribution of blasted rock. A consistent fragmentation size allows the company to streamline its process, and more importantly, minimize costs. In order to maintain this fragmentation size, monitoring must be done regularly so that adjustments can be made. Traditional methods such as manual sieving and visual estimation are have been used for this purpose, but limitations on sampling procedure and bias make these methods relatively inefficient. One of the solutions that were developed was to use digital image-based particle size analysis. The study proposes a cloud-based 3D photogrammetry rock fragmentation size distribution system that will make use of multiple images to create 3D models that can then be analyzed and segmented to provide a fragmentation size distribution. Several pictures of a muckpile using a smartphone are taken from an angle and compiled into a dataset. This is used as input for a Structure-from-Motion algorithm, which can create a 3D point cloud from the image data. This point cloud is then subjected to clustering so that the individual fragments can be represented and their dimensions could be measured. Finally, from these dimensions, a fragmentation size distribution can be created. As the system requires a large amount of computing power, it can be implemented in a remote server so that it can be accessible in the field. This system could provide surface mine operators an easy way to estimate size distribution using only a smartphone

Production and optical properties of liquid scintillator for the JSNS2^{2} experiment

The JSNS$^{2}$ (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) experiment will search for neutrino oscillations over a 24 m short baseline at J-PARC. The JSNS$^{2}$ inner detector will be filled with 17 tons of gadolinium-loaded liquid scintillator (LS) with an additional 31 tons of unloaded LS in the intermediate $\gamma$-catcher and outer veto volumes. JSNS$^{2}$ has chosen Linear Alkyl Benzene (LAB) as an organic solvent because of its chemical properties. The unloaded LS was produced at a refurbished facility, originally used for scintillator production by the RENO experiment. JSNS$^{2}$ plans to use ISO tanks for the storage and transportation of the LS. In this paper, we describe the LS production, and present measurements of its optical properties and long term stability. Our measurements show that storing the LS in ISO tanks does not result in degradation of its optical properties.Comment: 7 pages, 4 figures

Design and construction of a remote monitoring and control system for a dehumidifier combined with a heating module

Background: Protected cultivation (e.g., greenhouse) is spreading mainly for high-income crops such as paprika, strawberry, and tomato. The temperature and the humidity are especially important during cultivation. A dehumidifier combined with a heating module is under development. In the study, a remote monitoring and control system for the prototype was designed and constructed. Methods: The dehumidifier prototype was composed of a dehumidifier, a fan blower, and heating modules. The remote monitoring and control system was composed of temperature-humidity measuring sensor network, a central processing module, a dehumidifier network, and smartphone application. First, the sensing network was tested for different communication distances and number of data variables. Second, remote monitoring and control performance was tested using the smartphone application by signal intensity and time of the day. Results and discussion: Monitoring performance was favourable within 15 m distance with the tested ZigBee module, and a wireless communication network was established considering the communication distance and greenhouse length (i.e., 100 m). Remote monitoring and control was successful for all of the tested signal intensity and time of the day, although the data transmission speed was affected significantly. Components of the dehumidifier were successfully controlled within 30 s. Conclusion: The remote monitoring and control system was tested only under experimental conditions. For improved performance and practical application, the prototype needs to be further tested under crop growing conditions, and the control algorithm needs to be also improved

Discrete Ambiguities in the Measurement of the Weak Phase Gamma

Several time-independent methods have been devised for measuring the phase gamma of the Cabibbo-Kobayashi-Maskawa unitarity triangle. It is shown that such measurements generally suffer from discrete ambiguity which is at least 8-fold, not 4-fold as commonly stated. This has serious experimental implications, which are explored in methods involving B->DK decays. The measurement sensitivity and new physics discovery potential are estimated using a full Monte Carlo detector simulation with realistic background estimates.Comment: 15 pages, 2 figures, fixed typ