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1

Edelbro, Catrin. „Evaluation of rock mass strength criteria“. Licentiate thesis, Luleå, 2004. http://epubl.luth.se/1402-1757/2004/72.

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2

Eksi, M. „Rock mass characterisation for stability evaluation of room and pillar mine workings“. Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381206.

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3

Chester, Christopher James. „The evaluation of novel remote techniques for the detection of rock mass failure“. Thesis, University of Exeter, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438734.

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4

Ismail, Mohd Ashraf bin Mohamad. „Study on hydrogeological modeling and evaluation of groundwater behaviors in fractured rock mass“. 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120805.

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5

Poluga, Sara Lindsay. „Rock Mass Characterization and Stability Evaluation of Mount Rushmore National Memorial, Keystone, South Dakota“. Kent State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=kent1498239487032982.

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6

Chang, Chuan Sheng. „Development of Hydrogeological Modelling Method and Evaluation of Hydraulic Behaviors in Fractured Rock Mass“. 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/124510.

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7

Bryan-Jones, Alistair. „Evaluation of rock mass behaviour using borehole microseismic monitoring : an application to longwall coal mining“. Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366358.

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8

Clark, Philip B. „Rock mass and rippability evaluation for a proposed open pit mine at Globe-Progress, near Reefton“. Thesis, University of Canterbury. Geology, 1996. http://hdl.handle.net/10092/9361.

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Rock mass classification schemes such as the Q System and Rock Mass Rating (RMR) System have been designed for prediction of tunnel support, but these systems can be modified from stability analyses to excavatability assessments. Five methods have been used to classify the rock mass at Globe-Progress with the objective of predicting the type of equipment that may be used to excavate the open pit: • Seismic velocity determination • Size-Strength Method • RMRSystem • Weaver's (1975) Rippability Rating System • MacGregor et al's (1994) Productivity Prediction Method Seismic velocity determination and the Size-Strength Method are both easily performed during the feasibility stages of a project. Seismic velocities are influenced by the degree of fracturing, compaction, porosity, density and weathering, and they can therefore be used to provide a preliminary characterisation of the rock mass. The Size-Strength Method uses the two most important properties of a rock mass for classification, the discontinuity spacing and the strength of the rock material. Both methods, therefore, provide quick and accurate assessments of the rock mass quality. At the investigation or design stage of a project a complete rock mass characterisation method is used that involves a collection of geological and geotechnical parameters to fully characterise the rock mass. The method chosen for use at Globe-Progress was the RMR system, as this method is easily adapted from a stability prediction method to an excavatability prediction method. Most data required for calculation of the RMR Index is available from drillcore data logs. Simple analyses of drillcore log data show that drillcore data has been correctly logged except for the strength parameter. This was revised for every logged rock mass unit (RMU) based on quantitative strength determinations and the lithology of each RMU, so that more accurate excavatability analyses could be made using the RMR System, a modified version of Weaver's 1975 Rippability Rating Method, and MacGregor et al’s 1994 Productivity Prediction Method. The ratings for the three rock mass classification methods employed have been contoured on plans at 20 metre bench levels. The plans show that zones of poor rock, where digging to easy ripping should be expected, exist in the western pit wall, where the Chemist Shop Fault is located, and along the northern and eastern walls, following the Globe-Progress Shear Zone. Most of the overburden is classed as fair to poor rock, where easy to moderate ripping will be expected, and there is a zone of weaker rock in the axial fold of the Globe-Progress Shear Zone. This study indicates that the proposed open pit is geotechnically feasible to rip. The preliminary assessments suggest that 90% of the pit area is rippable or marginal and 10% is expected to non-rippable. The final assessments suggest that ripping will be very easy (>3500m³/hr) to difficult (250 - 750 m³/hr) using a Komatsu D575A-2 Bulldozer. Some areas of overburden may require blasting to further fragment the rock mass and aid productivity. But there are other factors, such as the bulldozer operator's experience in ripping similar rock masses, wear and tear on ripper blades, bulldozer maintenance time and transportation costs, and other restrictions that influence overall productivity and costs associated with ripping, and which cannot be determined until ripping actually proceeds.
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9

Elkarmoty, Mohamed Mohy Mohamed Saad <1987&gt. „Rock Mass Fracture Detection and Modelling Using GPR for Evaluation and Production Optimization of Ornamental Stone Deposits“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8370/1/Thesis_Mohamed%20Elkarmoty_PhD%20UNIBO.pdf.

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The thesis presents new solutions for the fractures problem in ornamental stone quarries which entails economic and material loses. The thesis aimed at developing methodologies and providing solutions for evaluation and production optimization of ornamental stone deposits. Ground Penetrating Radar (GPR) was selected, among several methods, as a fracture detection tool for this research. A combination of the use of a low frequency GPR antenna and laboratory rock tests for evaluation of an ornamental stone deposit showed encouraging results. Based on GPR survey, particularly high frequency antennas, a 3D deterministic fracture modeling approach was developed and implemented in several case studies of block and bench scales. A fracture index was proposed for deposit evaluation based on fracture detections from GPR survey. Additionally, an in-situ GPR test allowed formulating a propagation velocity model for 3D mapping of the dielectric constant of the medium, within macro and micro scale of the rock mass of a bench in a sandstone quarry. This finding is significant for future improvement of the deterministic accuracy level of the developed fracture modeling approach and, generally, for the GPR applications in rock mass. Regarding quarrying optimization, two 3D algorithms, based on fracture modeling or mapping, were developed for production and/or revenue optimization of cutting slabs from blocks and cutting blocks from benches. The algorithms were coded in two software packages named SlabCutOpt and BlockCutOpt. SlabCutOpt was applied to a case study of a limestone block through testing 37 different commercial-sizes of slabs, investigating the optimization results in terms of recovery ratio (a geo-environmental direction) and revenue (an economic direction). BlockCutOpt was applied to two case studies (quarries) with different site characteristics. The results showed that optimum cutting direction of blocks can vertically and horizontally vary, giving geometric information about the cutting grid of blocks that optimizes the production.
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10

Tranel, Lisa Marie. „Evaluation of Coupled Erosional Processes and Landscape Evolution in the Teton Range, Wyoming“. Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/38693.

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The evolution of mountain landscapes is controlled by complex interactions between large-scale tectonic, surficial and climate conditions. Dominant processes are attributed to creating characteristic features of the landscape, but topographic features are the cumulative result of coupled surficial processes, each locally effective in a different climate or elevation regime. The focus of erosion by glacial, fluvial, or mass wasting processes is highly sensitive to small changes in boundary conditions, therefore spatial and temporal variability can be high when observed over short time scales. This work evaluated methods for dissecting the history of complex alpine landscapes to understand the role of individual processes influenced by changing climate and underlying bedrock. It also investigated how individual and combined mechanisms of surficial processes influenced the evolution of topography in the Teton Range in Wyoming. Detrital apatite (U-Th)/He thermochronology and cosmogenic radionuclide erosion rates were applied to determine spatial and temporal variability of erosion in the central catchments of the range. Spatial variability existed between the glacial and fluvial systems, indicating that sediment erosion and deposition by these processes was controlled by short-term variability in climate conditions. Effective glacial incision also controlled other processes, specifically enhancing rock fall activity and inhibiting fluvial incision. Short-term erosion rates were highly variable and were controlled by stochastic processes, particularly hillslope failures in response to slope oversteepening due to glacial incision and orientation and spacing of bedrock fractures. Erosion rates averaged over 10 ky time scales were comparable to long-term exhumation rates measured in the Teton Range. The similarity of spatial erosion patterns to predicted uniform erosion and the balance between intermediate and long-term erosion rates suggests the landscape of the Teton Range is approaching steady-state, but frequent stochastic processes, short-term erosional variability and coupled processes maintain rugged topographic relief.
Ph. D.
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11

Benhalima, Mehdi. „Evaluation of the differences in characterization and classification of the rock mass quality : A comparison between pre-investigation, engineering geological forecast and tunnel mapping in the Northern Link project and the Cityline project“. Thesis, KTH, Jord- och bergmekanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-195743.

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In the construction of a tunnel, the characterization of the rock mass is performed in three different steps, in the pre-investigations, in the engineering geological forecast and in the tunnel mapping during construction. There has in previous work been observed that discrepancies exist between the results from these different steps, with a tendency to assign poorer rock mass quality in the tunnel mapping than in the pre-investigations and in the engineering geological forecast. One example is the work done by Kjellström [1] on the Cityline where the divergence in rock mass quality was analyzed between the different steps. If a divergence exists between the engineering geological forecast and the actual conditions observed in the tunnel mapping, it will influence both planning and budget. It is therefore important that the engineering geological forecast is as close as possible to the actual rock mass conditions in the field. The aim of this thesis was, using the case study of the Northern Link, to analyze those discrepancies in the rock mass quality estimated in the characterization and in the classification between the mapping of drill cores, the engineering geological forecast and the tunnel mapping thus complementing the work by Kjellström [1]. The aim was also identifying which parameters included in the Q-system that causes these discrepancies The analysis of the results showed that it is difficult to make the engineering geological forecast and the actual mapping match for every single meter, but that the overall correlation between them was good. The methodology used in the characterization and classification in the different phases (drill-core mapping, engineering geological forecast, tunnel mapping) may to some extent explain this divergence. The parameters Jr, Jn and Ja, included in the Q-system were the ones identified as having the largest influence on the discrepancies. In future work, it is recommended that focus is given on these parameters. A way to improve future engineering geological forecast for tunnel contracts would be to have a better follow up of the engineering geological forecast and to have standardized guidelines on how to assess clearly the value of the Q parameters in each phase (for the drill cores as well as for the actual mapping). The reduction of those differences would then lead to a better planning and budget management in future tunnel projects in Sweden.
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12

Elmo, Davide. „Evaluation of a hybrid FEM/DEM approach for determination of rock mass strength using a combination of discontinuity mapping and fracture mechanics modelling, with particular emphasis on modelling of jointed pillars“. Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439831.

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13

Sanchez, Caballero Lizeth Katherine. „Geostatistical modeling of geotechnical variables considering directional dependence“. Electronic Thesis or Diss., Université Paris sciences et lettres, 2022. https://thesesprivees.mines-paristech.fr/2022/2022UPSLM045_archivage.pdf.

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Avec la modélisation géologique et géométallurgique, la modélisation géotechnique est l'une des composantes essentielles de la planification et du développement de projets miniers à ciel ouvert et souterrains. Une caractéristique particulière de nombreuses variables géotechniques est d'être dépendante de la direction, c'est-à-dire que la mesure d'une carotte de sondage dépend non seulement de sa position géographique mais aussi de son orientation. Pour tenir compte de cette caractéristique, il est proposé de régionaliser les variables géotechniques dans un espace à cinq dimensions correspondant au produit sur l'espace géographique à trois dimensions et la sphère à deux dimensions, de sorte que chaque mesure soit indexée par ses coordonnées est, nord, élévation, azimut et pendage. Au lieu de faire des prédictions et des simulations conditionnées à une direction particulière, ce nouveau paradigme permet d'interpoler des variables géotechniques à n'importe quel endroit de l'espace géographique, et pour n'importe quelle direction. La structure de corrélation spatiale peut être inférée et modélisée en utilisant des covariances séparables ou des combinaisons de covariances séparables, sous une hypothèse de stationnarité dans l'espace géographique et d'isotropie sur la sphère. De plus, une simulation conditionnelle peut être effectuée par des méthodes spectrales ou de bandes tournantes, basées sur des produits de champs aléatoires stationnaires dans l'espace géographique et de champs aléatoires isotropes sur la sphère. La méthodologie proposée est illustrée par modélisation de la fréquence de discontinuité linéaire (P10), la désignation de la qualité de la roche (RQD), et le Slope Mass Rating (SMR) dans trois gisements miniers
Together with geological and geometallurgical modeling, geotechnical modeling is one of the essential components for the planning and development of open pit and underground mining projects. A particular characteristic of many geotechnical variables is to be direction-dependent, i.e., the measurement of a core sample not only depends on the in-situ position of this sample but also on its in-situ orientation. To account for this characteristic, it is proposed to regionalize such variables in a five-dimensional space corresponding to the product on the three-dimensional geographical space and the two-dimensional sphere, so that each measurement is indexed by its easting, northing, elevation, azimuth, and dip. Instead of making predictions and simulations conditioned to a particular direction, this new paradigm allows geotechnical variables to be interpolated at any place in the geographic space, for any direction. The spatial correlation structure can be inferred and modeled by using separable covariances or combinations of separable covariances, under an assumption of stationarity in the geographical space and isotropy on the sphere. Also, conditional simulation can be performed by turning bands, based on products of stationary random fields in the geographic space and isotropic random fields on the sphere. The proposed methodology is illustrated with the modeling of the linear discontinuity frequency (P10), the rock quality designation (RQD), and Slope Mass Rating (SMR) in three mineral deposits
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14

Young, Mimy. „Evaluation of Non-Contact Sampling and Detection of Explosives using Receiver Operating Characteristic Curves“. FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/994.

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The growing need for fast sampling of explosives in high throughput areas has increased the demand for improved technology for the trace detection of illicit compounds. Detection of the volatiles associated with the presence of the illicit compounds offer a different approach for sensitive trace detection of these compounds without increasing the false positive alarm rate. This study evaluated the performance of non-contact sampling and detection systems using statistical analysis through the construction of Receiver Operating Characteristic (ROC) curves in real-world scenarios for the detection of volatiles in the headspace of smokeless powder, used as the model system for generalizing explosives detection. A novel sorbent coated disk coined planar solid phase microextraction (PSPME) was previously used for rapid, non-contact sampling of the headspace containers. The limits of detection for the PSPME coupled to IMS detection was determined to be 0.5-24 ng for vapor sampling of volatile chemical compounds associated with illicit compounds and demonstrated an extraction efficiency of three times greater than other commercially available substrates, retaining >50% of the analyte after 30 minutes sampling of an analyte spike in comparison to a non-detect for the unmodified filters. Both static and dynamic PSPME sampling was used coupled with two ion mobility spectrometer (IMS) detection systems in which 10-500 mg quantities of smokeless powders were detected within 5-10 minutes of static sampling and 1 minute of dynamic sampling time in 1-45 L closed systems, resulting in faster sampling and analysis times in comparison to conventional solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis. Similar real-world scenarios were sampled in low and high clutter environments with zero false positive rates. Excellent PSPME-IMS detection of the volatile analytes were visualized from the ROC curves, resulting with areas under the curves (AUC) of 0.85-1.0 and 0.81-1.0 for portable and bench-top IMS systems, respectively. Construction of ROC curves were also developed for SPME-GC-MS resulting with AUC of 0.95-1.0, comparable with PSPME-IMS detection. The PSPME-IMS technique provides less false positive results for non-contact vapor sampling, cutting the cost and providing an effective sampling and detection needed in high-throughput scenarios, resulting in similar performance in comparison to well-established techniques with the added advantage of fast detection in the field.
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15

Moon, Joon-Shik. „Evaluation and assessment of inflow rates in tunnels excavated in jointed rock mass /“. 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3269985.

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Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007.
Source: Dissertation Abstracts International, Volume: 68-07, Section: B, page: 4676. Adviser: G. Fernandez. Includes bibliographical references (leaves 254-260) Available on microfilm from Pro Quest Information and Learning.
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16

Sebastian, Resmi. „Elastic Wave Propagation and Evaluation of Low Strain Dynamic Properties in Jointed Rocks“. Thesis, 2015. http://etd.iisc.ac.in/handle/2005/3653.

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When the point under consideration is not near to the source of vibration, the strains developed in the rock mass due to the passage of waves are usually of small magnitude, and within the elastic range. However, the rock mass may be subjected to a wide range of strain levels depending on the source of vibration and the wave frequency, even within the elastic limit. The present study is based on the two general conditions existing at field, long wave length propagation of waves and intermediate wavelength propagation of waves. When the wavelength of propagating wave is much longer than the joint spacing, it is referred to as long wavelength condition and is associated with propagation of low frequency waves across closely spaced joints. When wavelength of propagating wave is nearly equal to joint spacing, it is known as intermediate wavelength condition and is associated with propagation of high frequency waves. Long wave length propagation of waves has been studied by conducting laboratory experiments using Resonant Column Apparatus on developed plaster gypsum samples. The influence of joint types, joint spacing and joint orientation on wave propagation has been analyzed at three confining stresses under various strain levels. The wave velocities and damping ratios at various strain levels have been obtained and presented. Shear wave velocities are more dependent on confining stress than compression wave velocities across frictional joints whereas, compression wave velocities are more dependent on confining stress than shear wave velocities across filled joints. Wave velocities are at minimum and wave damping is at maximum across horizontal joints whereas wave velocities are at maximum and wave damping is at minimum across vertical joints. Shear wave velocity and shear wave damping are more dependent on joint orientations than compression wave velocity and compression wave damping. As Resonant Column Apparatus has some limitations in testing stiff samples, a validated numerical model has been developed using Discrete Element Method (DEM) that can provide resonant frequencies under torsional and flexural vibrations. It has been found from numerical simulations, that reduction of normal and shear stiffness of joint with increasing strain levels leads to wave velocity reduction in jointed rock mass. Intermediate wave length propagation of waves has been studied by conducting tests using Bender/ extender elements and the numerical simulations developed using 3DEC (Three Dimensional Distinct Element Code).Parametric study on energy transmission, wave velocities and wave amplitudes of shear and compression waves, has been carried out using the validated numerical model. The propagation of waves across multiple parallel joints was simulated and the phenomenon of multiple reflections of waves between joints could be observed. The transformations of obliquely incident waves on the joint have been successfully modeled by separating the transmitted transformed P and S waves. The frequency dependent behavior of jointed rocks has been studied by developing a numerical model and by applying a wide range of wave frequencies. It has been found that low frequency shear waves may involve slips of rock blocks depending on the strength of rock joint, leading to less transmission of energy; while low frequency compression waves are well transmitted across the joints. High frequency shear and compression waves experience multiple reflections and absorptions at joints.
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17

Sebastian, Resmi. „Elastic Wave Propagation and Evaluation of Low Strain Dynamic Properties in Jointed Rocks“. Thesis, 2015. http://etd.iisc.ernet.in/2005/3653.

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When the point under consideration is not near to the source of vibration, the strains developed in the rock mass due to the passage of waves are usually of small magnitude, and within the elastic range. However, the rock mass may be subjected to a wide range of strain levels depending on the source of vibration and the wave frequency, even within the elastic limit. The present study is based on the two general conditions existing at field, long wave length propagation of waves and intermediate wavelength propagation of waves. When the wavelength of propagating wave is much longer than the joint spacing, it is referred to as long wavelength condition and is associated with propagation of low frequency waves across closely spaced joints. When wavelength of propagating wave is nearly equal to joint spacing, it is known as intermediate wavelength condition and is associated with propagation of high frequency waves. Long wave length propagation of waves has been studied by conducting laboratory experiments using Resonant Column Apparatus on developed plaster gypsum samples. The influence of joint types, joint spacing and joint orientation on wave propagation has been analyzed at three confining stresses under various strain levels. The wave velocities and damping ratios at various strain levels have been obtained and presented. Shear wave velocities are more dependent on confining stress than compression wave velocities across frictional joints whereas, compression wave velocities are more dependent on confining stress than shear wave velocities across filled joints. Wave velocities are at minimum and wave damping is at maximum across horizontal joints whereas wave velocities are at maximum and wave damping is at minimum across vertical joints. Shear wave velocity and shear wave damping are more dependent on joint orientations than compression wave velocity and compression wave damping. As Resonant Column Apparatus has some limitations in testing stiff samples, a validated numerical model has been developed using Discrete Element Method (DEM) that can provide resonant frequencies under torsional and flexural vibrations. It has been found from numerical simulations, that reduction of normal and shear stiffness of joint with increasing strain levels leads to wave velocity reduction in jointed rock mass. Intermediate wave length propagation of waves has been studied by conducting tests using Bender/ extender elements and the numerical simulations developed using 3DEC (Three Dimensional Distinct Element Code).Parametric study on energy transmission, wave velocities and wave amplitudes of shear and compression waves, has been carried out using the validated numerical model. The propagation of waves across multiple parallel joints was simulated and the phenomenon of multiple reflections of waves between joints could be observed. The transformations of obliquely incident waves on the joint have been successfully modeled by separating the transmitted transformed P and S waves. The frequency dependent behavior of jointed rocks has been studied by developing a numerical model and by applying a wide range of wave frequencies. It has been found that low frequency shear waves may involve slips of rock blocks depending on the strength of rock joint, leading to less transmission of energy; while low frequency compression waves are well transmitted across the joints. High frequency shear and compression waves experience multiple reflections and absorptions at joints.
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18

Cameron-Clarke, Ian Stuart. „An evaluation of the reliability of borehole core data in engineering rock mass classification systems“. Thesis, 2015. http://hdl.handle.net/10539/16481.

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19

Liu, Hsing-Chih, und 劉星馳. „Accuracy of Ultrasound-Based Bone Mass Density (BMD) for Classification and Yield of Osteoporosis-Evaluation by Recevicer Operating Characteristic (ROC) method“. Thesis, 2010. http://ndltd.ncl.edu.tw/handle/22187745664489331838.

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碩士
臺灣大學
流行病學研究所
98
The gold standard for osteoporosis diagnosis is bone mass density (BMD) detected by dual energy X-ray absorptiometry (DXA), however DXA is not a suitable tool on population screening. Recently, the quantitative ultrasound (QUS) tool was developing as a BMD screening tool in population screening, but the accuracy of QUS tool has not yet been identified. We collected population BMD screening data from 1999 to 2004, there are 41245 people with 39512 are non-osteoporosis and 1733 are diagnosed to be osteoporosis. Using QUS as BMD screening tool had sensitivity of 0.58(95%CI: 0.55-0.60) and sensitivity of 0.66 (95%CI: 0.64- 0.69) at cut-off point BMD T score≦-2SD.To predict individual accuracy of QUS tool we used regression model to analysis, dichotomous BMD value as dependent variable and risk factors based on FRAX which to be age、gender、BMI above or below 25、milk intake three days or more per week、coffee intake three days or more per week、before or after menopause as independent variables. ROC curve is to analysis the accuracy at possible cut-off point, and AUC range 0.59-0.71 at different population under binormal distribution. After modeling the effect of covariate on test result, we developed the predictive test result of individual and build individual ROC curve at each possible cut-off point of QUS tool. Take individual information in to consideration would elevate the accuracy of QUS tool. Estimated the performance by regression model had AUC 0.81, this result performs similarly well as the simulation result which to be 0.79 in previous study. In this, we develop QUS tool to become a more accurate screening tool in BMD screening.
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