90 research outputs found
APPLICATION OF GEOSTATISTICS IN THE ESTIMATION OF SUJISHAN GRAPHITE DEPOSITS, MONGOLIA
No full textIn this paper, the author used mine 3D software to establish the 3D geological model of Sujishan Graphite deposit, and applied geostatistics to estimate the resource, offered references for next exploration and mining. Surpac was used to set up geological database of Sujishan Graphite deposit, topographical DTM, ore body model and grade model, 3D of drilling database, also analysis the spatial grade distribution in reality. Based on geostatistics, drilling samples are composited and statistically analysed and eliminate the impact of outliers. Experimental variograms were constructed for the striking, dipping and vertical directions. Grade and resource are estimated by ordinary kriging. Comparing to the traditional estimation methods, this 3D software gives reliable estimation, which provides references for dynamic management of mine's resource
A General Framework for a Collaborative Mobile Indoor Navigation Assistance System
No full textReliance on a fully autonomous system often requires well specified maps and sensors in the environment, making the system not easily extensible to new or changing environ-ments. Given the increasingly ubiquitous network connec-tions, one way to provide quick and robust spatial assistance is to connect local users to an expert user at a remote location, such that direct guidance can be provided. This workshop pa-per proposes a general framework for such a remote spatial assistance system. The goal of the system is to provide a cost-effective method to effectively transfer what the user is seeing to a remote expert who is familiar with the area (e.g., providing museum tours, guiding a lost pedestrian, providing guided emergency response to an area struck by hurricane), such that interactive assistance can be provided to the local user using augmented reality techniques. We propose that this framework contains three major components: 1) Spatial plans generation; 2) Context-aware positioning and error cor-rection; 3) Collaborative guidance with augmented reality in-terfaces. Author Keywords Remote spatial assistance, augmented reality, mobile indoor navigation, collaborative system ACM Classification Keywords K.4.3 Organizational Impacts: Computer-supported collaborative wor
Real-time Fusion of Multi-Source Monitoring Data with Geotechnical Numerical Model Results using Data-driven and Physics-informed Sparse Dictionary Learning
No full textDevelopment of digital twins is emerging rapidly in geotechnical engineering, and it often requires real-time updating of numerical models (e.g., finite element model, FEM) using multiple sources of monitoring data (e.g., settlement and pore water pressure data). Conventional model updating, or calibration, often involves repeated executions of the numerical model, using monitoring data from a specific source or at limited spatial locations only. This leads to a critical research need of real-time model updating and predictions using a numerical model improved continuously by multi-source monitoring data. To address this need, a physics-informed machine learning method called multi-source sparse dictionary learning (MS-SDL) is proposed in this study. Originated from signal decomposition and compression, MS-SDL utilizes results from a suite of numerical models as basis functions, or dictionary atoms, and employs multi-source monitoring data to select a limited number of important atoms for predicting multiple, spatiotemporally varying geotechnical responses. As monitoring data are collected sequentially, no repeated evaluations of computational numerical models are needed, and an automatic and real-time model calibration is achieved for continuously improving model predictions. A real project in Hong Kong is presented to illustrate the proposed approach. Effect of monitoring data from different sources is also investigated.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Bayesian Design of Noninferiority Clinical Trials with Co-primary Endpoints and Multiple Dose Comparison
No full text黄河口海域潮汐、潮流、余流、切变锋数值模拟
No full textA 3-D Finite-Volume Coastal Ocean Model was applied in the Bohai Sea, especially near the Yellow River estuary, to simulate the tides, tidal currents, residual currents and shear fronts, using unstructured triangular grids. In the case of an accurate simulation of the tides and tidal currents in the Bohai Sea, this article focuses on the Yellow River mouth. The type of tides is irregular semi-diurnal and the type of tidal currents is the reciprocating flow, mostly parallel to the coastline. The tide induced eulerian residual currents are a couple of eddies on each side of the river mouth, with the anticlockwise on the left side and clockwise on the other side, and both of the eddies are enhanced by the Yellow River runoff. Two patterns of shear fronts are identified at the conversion between the flood and ebb tidal phase. The results suggest that the shear fronts be generated in the shallow water because the tidal phase of the coastal area is ahead of the deeper seaward area, then moves seaward and finally disappears 1-2 hours later.Publishe
Depolymerization kinetics of di(4-tert-butyl cyclohexyl) itaconate and Mark-Houwink-Kuhn-Sakurada parameters of di(4-tert- butyl cyclohexyl) itaconate and di-n-butyl itaconate
No full textMultipulse pulsed laser polymerization coupled with size exclusion chromatography (MP-PLP-SEC) has been employed to study the depropagation kinetics of the sterically demanding 1,1-disubstituted monomer di(4-tert-butylcyclohexyl) itaconate (DBCHI). The effective rate coefficient of propagation, kp eff, was determined for a solution of monomer in anisole at concentrations, cM 0, 0.72 and 0.88 mol L-1 in the temperature range 0 ≤ T ≤ 70°C. The resulting Arrhenius plot (i.e., ln kp eff vs. 1/RT) displayed a subtle curvature in the higher temperature regime and was analyzed in the linear part to yield the activation parameters of the forward reaction. In the temperature region where no depropagation was observed (0 ≤ T ≤ 50°C), the following Arrhenius parameters for kp were obtained (DBCHI, Ep = 35.5 ± 1.2 kJ mol-1, ln Ap = 14.8 ± 0.5 L mol-1 s-1). In addition, the k p eff data was analyzed in the depropagatation regime for DBCHI, resulting in estimates for the associated entropy (-ΔS = 150 J mol-1 K-1) of polymerization. With decreasing monomer concentration and increasing temperature, it is increasingly more difficult to obtain well structured molecular weight distributions. The Mark-Houwink-Kuhn- Sakurada (MHKS) parameters for di-n-butyl itaconate (DBI) and DBCHI were determined using a triple detection GPC system incorporating online viscometry and multi-angle laser light scattering in THF at 40°C. The MHKS for poly-DBI and poly-DBCHI in the molecular weight range 35-256 kDa and 36.5-250 kDa, respectively, were determined to be KDBI = 24.9 (103 mL g-1), αDBI = 0.58, KDBCHI = 12.8 (10 3 mL g-1), and αDBCHI = 0.63. © 2006 Wiley Periodicals, Inc
Side wall effects on ship model testing in a towing tank
No full textDue to the existence of the side walls in a towing tank, the measured hydrodynamic forces would present some discrepancies compared to the open sea results. This phenomenon is referred to as the side wall effect. The objective of the present study is to investigate the side wall effects on ship model testing in a towing tank. The method used in the present study involves a 3D panel method based on the Rankine type Green function. Both the steady and unsteady problems were investigated numerically. The numerical results were validated against ship model test results. After the validations, a large scale computations were performed to investigate the parameters which could determine the side wall effects. Two diagrams of side wall effects (one in calm water and the other one in waves), were obtained which showed whether the side wall effect was less than the permissible error to be included in the measured values
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