Multivariate online kernel density estimation with Gaussian kernels

We propose a novel approach to online estimation of probability density functions, which is based on kernel density estimation (KDE). The method maintains and updates a non-parametric model of the observed data, from which the KDE can be calculated. We propose an online bandwidth estimation approach and a compression/revitalization scheme which maintains the KDE's complexity low. We compare the proposed online KDE to the state-of-the-art approaches on examples of estimating stationary and non-stationary distributions, and on examples of classification. The results show that the online KDE outperforms or achieves a comparable performance to the state-of-the-art and produces models with a significantly lower complexity while allowing online adaptation.     

Automated construction activity monitoring system

Building activities are inadequately monitored during construction projects when attempting to satisfy the need for information, especially in those cases of unforeseen events and conditions on-site. Many IT-supported methods have been introduced, but so far none has been able to deliver satisfactory and reliable information. This paper presents a combined method, consisting of three components: an automated activity tracking subsystem based on image recognition, an automated material tracking subsystem, and a mobile computing supported communication environment. All subsystems are based on the same 4D model of a building.     

Integrating resource production and construction using BIM

This paper presents the outcomes of a research and development project carried out at the University of Maribor, Construction IT Centre, with regard to the introduction of a building information model (BIM) and a model based construction process into the operational environment of a construction company. The initiative for the project came from the industry and was performed as a joined effort of the research organization and the construction company. Work was performed in the scope of an industrialized construction environment, with the main aim to integrate mass production prefabrication processes with construction site activities. BIM was used as a link between an enterprise resource planning (ERP) information system that supports manufacturing process and construction object related information, mainly handled by CAD tools. The benefits of this link are presented with regard to project progress monitoring and material flow management.     

Integrated Information System Supporting Road Design, Evaluation, and Construction

Road design, evaluation (analysis), and construction are closely connected processes in which design and analysis are iterated to converge on the optimal solution. Many errors and delays frequently appear when data are exchanged between particular tasks; intertask connections are therefore of great importance for the quality of the final product. This article describes an integrated information system that is intended to support all important stages of the road life cycle: design, evaluation (through different analysis procedures), and construction. The concept of the system is object oriented. However, existing program packages are included to solve some common tasks. The system includes a conventional relational database as well as a spatial database with all relevant geographic information system (GIS) functionality. Since particular tasks often are executed at different places and by different companies, the interconnections are supported by a special metafile that contains all specific data about the project as it progresses toward the construction phase.     

New Primary Dew-Point Generators at HMI/FSB-LPM in the Range from ?70?°C to +60?°C

To extend the dew-point range and to improve the uncertainties of the humidity scale realization at HMI/FSB-LPM, new primary low- and high-range dew-point generators were developed and implemented in cooperation with MIKES, in 2009 through EUROMET Project No. 912. The low-range saturator is designed for primary realization of the dew-point temperature scale from ?70?°C to +?5?°C, while the high-range saturator covers the range from 1?°C to 60?°C. The system is designed as a single-pressure, single-pass dew-point generator. MIKES designed and constructed both the saturators to be implemented in dew-point calibration systems at LPM. The LPM took care of purchasing and adapting liquid baths, of implementing the temperature and pressure measurement equipment appropriate for use in the systems, and development of gas preparation and flow control systems as well as of the computer-based automated data acquisition. The principle and the design of the generator are described in detail and schematically depicted. The tests were performed at MIKES to investigate how close both the saturators are to an ideal saturator. Results of the tests show that both the saturators are efficient enough for a primary realization of the dew-point temperature scale from ?70?°C to +?60?°C, in the specified flow-rate ranges. The estimated standard uncertainties due to the non-ideal saturation efficiency are between 0.02?°C and 0.05?°C.     

Input Shaping of the Synchronous Generator for Reduction of Self‐induced Oscillations

This article suggests the application of input shaping for the elimination of electromechanical oscillations arising from changes in the operating point of the synchronous generator. Poorly damped poles are the cause of electromechanical oscillations of the synchronous generator. Various power system stabilizers (PSS) are now used to reduce the electromechanical oscillations. Input shaping is a feedforward control and therefore does not require the measurement of electrical and mechanical quantities of the synchronous generator unlike the PSS. It is possible to apply the input shaping for the excitation system of synchronous generators with or without PSS.     

Signal enhancement in HPLC/microcoil NMR using automated column trapping

A new HPLC NMR system is described that performs analytical separation, preconcentration, and NMR spectroscopy in rapid succession. The central component of our method is the online preconcentration sequence that improves the match between postcolumn analyte peak volume and microcoil NMR detection volume. Separated samples are collected on to a C18 guard column with a mobile phase composed of 90% D2O/10% acetonitrile-D3 and back-flushed to the NMR microcoil probe with 90% acetonitrile-D3/10% D2O. To assess the performance of our unit, we separated a standard mixture of 1 mM ibuprofen, naproxen, and phenylbutazone using a commercially available C18 analytical column. The S/N measurements from the NMR acquisitions indicated that we achieved signal enhancement factors up to 10.4 (+/-1.2)-fold. Furthermore, we observed that preconcentration factors increased as the injected amount of analyte decreased. The highest concentration enrichment of 14.7 (+/-2.2)-fold was attained injecting 100 microL of solution of 0.2 mM (approximately 4 microg) ibuprofen.     

Composites Ag5Pb2O6/M (M=CuO, Cu2O) and Exciton Models of Superconductivity

Resistive properties of composites Ag₅Pb₂O₆/M (M=CuO, Cu₂O) have been studied in the vicinity of the percolation threshold (concentration w/w～0.48). Metallic particles of the Byström-Evers oxide Ag₅Pb₂O₆ are covered by an overlayer of Cu₂O (～8 nm). Measurements suggest the exciton type superconductivity originally proposed by Little 1D model and extended to the 2D configuration by Ginzburg. An application of the Ginzburg model to the Ag₅Pb₂O₆ particles dressed in the Cu₂O overlayer involves monovalent Ag₂ dimers moving in the hexagonal channels of the Ag₅Pb₂O₆ lattice. Dimers are considered be unsaturated on the grain surface. It is applied to the Swiss cheese model of the percolation, and dielectric holes between metallic particles are assumed to act as resonant microcavities driving the strong coupling of the photon field to excitons in the Cu₂O overlayer. Accordingly, polariton states may be created and possible polariton mechanism of the superconductivity is discussed in terms of the model put forward by Laussy and coworkers.