93. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

93. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY SOUTH OF KIMBERLY, IDAHO; OVERALL NORTHEAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

114. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

114. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OVERALL VIEW, WEST OF INLET SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OVERALL VIEW OF SIPHON, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; CLOSE-UP OF INLET SIDE OF SIPHON, NORTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

116. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

116. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; CLOSE-UP OF OUTLET, DIVERSION SPILL IN BACKGROUND, WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Solid images generated from UAVs to analyze areas affected by rock falls

NASA Astrophysics Data System (ADS)

Giordan, Daniele; Manconi, Andrea; Allasia, Paolo; Baldo, Marco

2015-04-01

The study of rock fall affected areas is usually based on the recognition of principal joints families and the localization of potential instable sectors. This requires the acquisition of field data, although as the areas are barely accessible and field inspections are often very dangerous. For this reason, remote sensing systems can be considered as suitable alternative. Recently, Unmanned Aerial Vehicles (UAVs) have been proposed as platform to acquire the necessary information. Indeed, mini UAVs (in particular in the multi-rotors configuration) provide versatility for the acquisition from different points of view a large number of high resolution optical images, which can be used to generate high resolution digital models relevant to the study area. By considering the recent development of powerful user-friendly software and algorithms to process images acquired from UAVs, there is now a need to establish robust methodologies and best-practice guidelines for correct use of 3D models generated in the context of rock fall scenarios. In this work, we show how multi-rotor UAVs can be used to survey areas by rock fall during real emergency contexts. We present two examples of application located in northwestern Italy: the San Germano rock fall (Piemonte region) and the Moneglia rock fall (Liguria region). We acquired data from both terrestrial LiDAR and UAV, in order to compare digital elevation models generated with different remote sensing approaches. We evaluate the volume of the rock falls, identify the areas potentially unstable, and recognize the main joints families. The use on is not so developed but probably this approach can be considered the better solution for a structural investigation of large rock walls. We propose a methodology that jointly considers the Structure from Motion (SfM) approach for the generation of 3D solid images, and a geotechnical analysis for the identification of joint families and potential failure planes.

High-resolution three-dimensional imaging and analysis of rock falls in Yosemite valley, California

USGS Publications Warehouse

Stock, Gregory M.; Bawden, G.W.; Green, J.K.; Hanson, E.; Downing, G.; Collins, B.D.; Bond, S.; Leslar, M.

2011-01-01

We present quantitative analyses of recent large rock falls in Yosemite Valley, California, using integrated high-resolution imaging techniques. Rock falls commonly occur from the glacially sculpted granitic walls of Yosemite Valley, modifying this iconic landscape but also posing signifi cant potential hazards and risks. Two large rock falls occurred from the cliff beneath Glacier Point in eastern Yosemite Valley on 7 and 8 October 2008, causing minor injuries and damaging structures in a developed area. We used a combination of gigapixel photography, airborne laser scanning (ALS) data, and ground-based terrestrial laser scanning (TLS) data to characterize the rock-fall detachment surface and adjacent cliff area, quantify the rock-fall volume, evaluate the geologic structure that contributed to failure, and assess the likely failure mode. We merged the ALS and TLS data to resolve the complex, vertical to overhanging topography of the Glacier Point area in three dimensions, and integrated these data with gigapixel photographs to fully image the cliff face in high resolution. Three-dimensional analysis of repeat TLS data reveals that the cumulative failure consisted of a near-planar rock slab with a maximum length of 69.0 m, a mean thickness of 2.1 m, a detachment surface area of 2750 m2, and a volume of 5663 ?? 36 m3. Failure occurred along a surfaceparallel, vertically oriented sheeting joint in a clear example of granitic exfoliation. Stress concentration at crack tips likely propagated fractures through the partially attached slab, leading to failure. Our results demonstrate the utility of high-resolution imaging techniques for quantifying far-range (>1 km) rock falls occurring from the largely inaccessible, vertical rock faces of Yosemite Valley, and for providing highly accurate and precise data needed for rock-fall hazard assessment. ?? 2011 Geological Society of America.

Quantitative rock-fall hazard and risk assessment for Yosemite Valley, Yosemite National Park, California

USGS Publications Warehouse

Stock, Greg M.; Luco, Nicolas; Collins, Brian D.; Harp, Edwin L.; Reichenbach, Paola; Frankel, Kurt L.

2012-01-01

caused injuries within developed regions located on or adjacent to talus slopes, highlighting the need for additional investigations into rock-fall hazard and risk. This assessment builds upon previous investigations of rock fall hazard and risk in Yosemite Valley (Wieczorek et al., 1998, 1999; Guzzetti et al., 2003; Wieczorek et al., 2008), and focuses on hazard and risk to structures posed by relatively frequent fragmental-type rock falls (Evans and Hungr, 1999), up to approximately 100,000 m3 in volume.

A custom acoustic emission monitoring system for harsh environments: application to freezing-induced damage in alpine rock-walls

NASA Astrophysics Data System (ADS)

Girard, L.; Beutel, J.; Gruber, S.; Hunziker, J.; Lim, R.; Weber, S.

2012-06-01

We present a custom acoustic emission (AE) monitoring system designed to perform long-term measurements on high-alpine rock-walls. AE monitoring is a common technique for characterizing damage evolution in solid materials. The system is based on a two-channel AE sensor node (AE-node) integrated into a Wireless Sensor Network (WSN) customized for operation in harsh environments. This wireless architecture offers flexibility in the deployment of AE-nodes at any position of the rock-wall that needs to be monitored, within a range of a few hundred meters from a core station connected to the internet. The system achieves near real-time data delivery and allows the user to remotely control the AE detection threshold. In order to protect AE sensors and capture acoustic signals from specific depths of the rock-wall, a special casing was developed. The monitoring system is completed by two probes that measure rock temperature and liquid water content, both probes being also integrated into the WSN. We report a first deployment of the monitoring system on a rock-wall at Jungfraujoch, 3500 m a.s.l., Switzerland. While this first deployment of the monitoring system aims to support fundamental research on processes that damage rock under cold climate, the system could serve a number of other applications, including rock-fall hazard surveillance or structural monitoring of concrete structures.

A custom acoustic emission monitoring system for harsh environments: application to freezing-induced damage in alpine rock walls

NASA Astrophysics Data System (ADS)

Girard, L.; Beutel, J.; Gruber, S.; Hunziker, J.; Lim, R.; Weber, S.

2012-11-01

We present a custom acoustic emission (AE) monitoring system designed to perform long-term measurements on high-alpine rock walls. AE monitoring is a common technique for characterizing damage evolution in solid materials. The system is based on a two-channel AE sensor node (AE-node) integrated into a wireless sensor network (WSN) customized for operation in harsh environments. This wireless architecture offers flexibility in the deployment of AE-nodes at any position of the rock wall that needs to be monitored, within a range of a few hundred meters from a core station connected to the internet. The system achieves near real-time data delivery and allows the user to remotely control the AE detection threshold. In order to protect AE sensors and capture acoustic signals from specific depths of the rock wall, a special casing was developed. The monitoring system is completed by two probes that measure rock temperature and liquid water content, both probes being also integrated into the WSN. We report a first deployment of the monitoring system on a rock wall at Jungfraujoch, 3500 m a.s.l., Switzerland. While this first deployment of the monitoring system aims to support fundamental research on processes that damage rock under cold climate, the system could serve a number of other applications, including rock fall hazard surveillance or structural monitoring of concrete structures.

Verifying the new luminescence surface-exposure dating technique--rock falls in Canyonlands National Park, Utah

NASA Astrophysics Data System (ADS)

Pederson, J. L.; Sohbati, R.; Murray, A. S.; Jain, M.

2015-12-01

Recent studies have helped develop the optically stimulated luminescence (OSL) dating of rock surfaces, as applied to the age of the famous Great Gallery rock art panel in Canyonlands National Park. Chapot et al. (2012) dated a key rock fall to ~900 yrs ago by applying OSL to the outer 1-mm buried surface of a sandstone talus boulder, an age confirmed by independent radiocarbon dating. Later, in a novel approach and with the use of a local known-age calibration sample, Sohbati et al. (2012) modelled the millimeter-scale OSL-depth profile to determine a pre-burial exposure duration of ~700 years for the same rock fall. This combination of rock-fall dating and exposure dating--an approach with broad potential to date Holocene mass movements--constrains the creation of the Great Gallery rock art to a time window of 900 to ~1600 years ago (Pederson et al., 2014), a result met with some controversy. Here we report on a new phase of research to verify these results and further refine OSL-profile exposure dating for mass movements. New analyses from within and near the Great Gallery alcove include: i) exposure dating of the same alcove surface upon which the rock art is painted with a predicted exposure age of ~1600 years; ii) exposure dating of the top (light-exposed) side of the same rock-fall boulder whose buried side was previously dated to test for reproduction of the known age; and iii) an improved calibration sample from a nearby trail/road-cut for verification. The residual OSL signal is measured with depth in millimeter-thick increments of all samples. We first determine the site-specific luminescence reduction rate at the rock surface by fitting the OSL surface-exposure dating model to the calibration profile from the trail/road-cut. This parameterized model then provides exposure ages for the bleaching profiles observed in the other samples. Results have implications for the application of OSL rock-surface and exposure-profile dating in other settings where

A Review of Rock Bolt Monitoring Using Smart Sensors.

PubMed

Song, Gangbing; Li, Weijie; Wang, Bo; Ho, Siu Chun Michael

2017-04-05

Rock bolts have been widely used as rock reinforcing members in underground coal mine roadways and tunnels. Failures of rock bolts occur as a result of overloading, corrosion, seismic burst and bad grouting, leading to catastrophic economic and personnel losses. Monitoring the health condition of the rock bolts plays an important role in ensuring the safe operation of underground mines. This work presents a brief introduction on the types of rock bolts followed by a comprehensive review of rock bolt monitoring using smart sensors. Smart sensors that are used to assess rock bolt integrity are reviewed to provide a firm perception of the application of smart sensors for enhanced performance and reliability of rock bolts. The most widely used smart sensors for rock bolt monitoring are the piezoelectric sensors and the fiber optic sensors. The methodologies and principles of these smart sensors are reviewed from the point of view of rock bolt integrity monitoring. The applications of smart sensors in monitoring the critical status of rock bolts, such as the axial force, corrosion occurrence, grout quality and resin delamination, are highlighted. In addition, several prototypes or commercially available smart rock bolt devices are also introduced.

A Review of Rock Bolt Monitoring Using Smart Sensors

PubMed Central

Song, Gangbing; Li, Weijie; Wang, Bo; Ho, Siu Chun Michael

2017-01-01

Rock bolts have been widely used as rock reinforcing members in underground coal mine roadways and tunnels. Failures of rock bolts occur as a result of overloading, corrosion, seismic burst and bad grouting, leading to catastrophic economic and personnel losses. Monitoring the health condition of the rock bolts plays an important role in ensuring the safe operation of underground mines. This work presents a brief introduction on the types of rock bolts followed by a comprehensive review of rock bolt monitoring using smart sensors. Smart sensors that are used to assess rock bolt integrity are reviewed to provide a firm perception of the application of smart sensors for enhanced performance and reliability of rock bolts. The most widely used smart sensors for rock bolt monitoring are the piezoelectric sensors and the fiber optic sensors. The methodologies and principles of these smart sensors are reviewed from the point of view of rock bolt integrity monitoring. The applications of smart sensors in monitoring the critical status of rock bolts, such as the axial force, corrosion occurrence, grout quality and resin delamination, are highlighted. In addition, several prototypes or commercially available smart rock bolt devices are also introduced. PMID:28379167

Highly Portable, Sensor-Based System for Human Fall Monitoring

PubMed Central

Mao, Aihua; Ma, Xuedong; He, Yinan; Luo, Jie

2017-01-01

Falls are a very dangerous situation especially among elderly people, because they may lead to fractures, concussion, and other injuries. Without timely rescue, falls may even endanger their lives. The existing optical sensor-based fall monitoring systems have some disadvantages, such as limited monitoring range and inconvenience to carry for users. Furthermore, the fall detection system based only on an accelerometer often mistakenly determines some activities of daily living (ADL) as falls, leading to low accuracy in fall detection. We propose a human fall monitoring system consisting of a highly portable sensor unit including a triaxis accelerometer, a triaxis gyroscope, and a triaxis magnetometer, and a mobile phone. With the data from these sensors, we obtain the acceleration and Euler angle (yaw, pitch, and roll), which represents the orientation of the user’s body. Then, a proposed fall detection algorithm was used to detect falls based on the acceleration and Euler angle. With this monitoring system, we design a series of simulated falls and ADL and conduct the experiment by placing the sensors on the shoulder, waist, and foot of the subjects. Through the experiment, we re-identify the threshold of acceleration for accurate fall detection and verify the best body location to place the sensors by comparing the detection performance on different body segments. We also compared this monitoring system with other similar works and found that better fall detection accuracy and portability can be achieved by our system. PMID:28902149

Highly Portable, Sensor-Based System for Human Fall Monitoring.

PubMed

Mao, Aihua; Ma, Xuedong; He, Yinan; Luo, Jie

2017-09-13

Falls are a very dangerous situation especially among elderly people, because they may lead to fractures, concussion, and other injuries. Without timely rescue, falls may even endanger their lives. The existing optical sensor-based fall monitoring systems have some disadvantages, such as limited monitoring range and inconvenience to carry for users. Furthermore, the fall detection system based only on an accelerometer often mistakenly determines some activities of daily living (ADL) as falls, leading to low accuracy in fall detection. We propose a human fall monitoring system consisting of a highly portable sensor unit including a triaxis accelerometer, a triaxis gyroscope, and a triaxis magnetometer, and a mobile phone. With the data from these sensors, we obtain the acceleration and Euler angle (yaw, pitch, and roll), which represents the orientation of the user's body. Then, a proposed fall detection algorithm was used to detect falls based on the acceleration and Euler angle. With this monitoring system, we design a series of simulated falls and ADL and conduct the experiment by placing the sensors on the shoulder, waist, and foot of the subjects. Through the experiment, we re-identify the threshold of acceleration for accurate fall detection and verify the best body location to place the sensors by comparing the detection performance on different body segments. We also compared this monitoring system with other similar works and found that better fall detection accuracy and portability can be achieved by our system.

Chronology of rock falls and slides in a desert mountain range: Case study from the Sonoran Desert in south-central Arizona

NASA Astrophysics Data System (ADS)

Dorn, Ronald I.

2014-10-01

In order to respond to the general paucity of information on the chronology of ubiquitous small rock falls and slides that litter the slopes of desert mountain ranges, a case study in the Sonoran Desert reveals new insight into the desert geomorphology of mountain slopes. Rock falls and rock slides in the McDowell Mountains that abut metropolitan Phoenix, USA, fall in three chronometric groupings dated by conventional radiocarbon and rock varnish microlamination methods. First, the oldest events are > 74 ka and take the form of stable colluvial boulder fields - positive relief features that are tens of meters long and a few meters wide. Second, randomly sampled slides and falls of various sizes and positions wasted during wetter periods of the terminal Pleistocene and Holocene. Third, an anomalous clustering of slides and falls occurred during the late Medieval Warm Period (Medieval Climatic Anomaly) when an extreme storm was a possible but unlikely trigger. One speculative hypothesis for the cluster of Medieval Warm Period events is that a small to moderate sized earthquake shook heavily shattered bedrock - close to failure - just enough to cause a spate of rock falls and slides. A second speculative hypothesis is that this dry period enhanced physical weathering processes such as dirt cracking. However, the reasons for the recent clustering of rock falls remain enigmatic. While the temporal distribution of slides and falls suggests a minimal hazard potential for homes and roads on the margins of the McDowell Mountains, this finding may not necessary match other desert ranges in metropolitan Phoenix or mountains with different rock types and structures that abut other arid urban centers.

Automatic fall monitoring: a review.

PubMed

Pannurat, Natthapon; Thiemjarus, Surapa; Nantajeewarawat, Ekawit

2014-07-18

Falls and fall-related injuries are major incidents, especially for elderly people, which often mark the onset of major deterioration of health. More than one-third of home-dwelling people aged 65 or above and two-thirds of those in residential care fall once or more each year. Reliable fall detection, as well as prevention, is an important research topic for monitoring elderly living alone in residential or hospital units. The aim of this study is to review the existing fall detection systems and some of the key research challenges faced by the research community in this field. We categorize the existing platforms into two groups: wearable and ambient devices; the classification methods are divided into rule-based and machine learning techniques. The relative merit and potential drawbacks are discussed, and we also outline some of the outstanding research challenges that emerging new platforms need to address.

Automatic Fall Monitoring: A Review

PubMed Central

Pannurat, Natthapon; Thiemjarus, Surapa; Nantajeewarawat, Ekawit

2014-01-01

Falls and fall-related injuries are major incidents, especially for elderly people, which often mark the onset of major deterioration of health. More than one-third of home-dwelling people aged 65 or above and two-thirds of those in residential care fall once or more each year. Reliable fall detection, as well as prevention, is an important research topic for monitoring elderly living alone in residential or hospital units. The aim of this study is to review the existing fall detection systems and some of the key research challenges faced by the research community in this field. We categorize the existing platforms into two groups: wearable and ambient devices; the classification methods are divided into rule-based and machine learning techniques. The relative merit and potential drawbacks are discussed, and we also outline some of the outstanding research challenges that emerging new platforms need to address. PMID:25046016

Utilization of advanced calibration techniques in stochastic rock fall analysis of quarry slopes

NASA Astrophysics Data System (ADS)

Preh, Alexander; Ahmadabadi, Morteza; Kolenprat, Bernd

2016-04-01

In order to study rock fall dynamics, a research project was conducted by the Vienna University of Technology and the Austrian Central Labour Inspectorate (Federal Ministry of Labour, Social Affairs and Consumer Protection). A part of this project included 277 full-scale drop tests at three different quarries in Austria and recording key parameters of the rock fall trajectories. The tests involved a total of 277 boulders ranging from 0.18 to 1.8 m in diameter and from 0.009 to 8.1 Mg in mass. The geology of these sites included strong rock belonging to igneous, metamorphic and volcanic types. In this paper the results of the tests are used for calibration and validation a new stochastic computer model. It is demonstrated that the error of the model (i.e. the difference between observed and simulated results) has a lognormal distribution. Selecting two parameters, advanced calibration techniques including Markov Chain Monte Carlo Technique, Maximum Likelihood and Root Mean Square Error (RMSE) are utilized to minimize the error. Validation of the model based on the cross validation technique reveals that in general, reasonable stochastic approximations of the rock fall trajectories are obtained in all dimensions, including runout, bounce heights and velocities. The approximations are compared to the measured data in terms of median, 95% and maximum values. The results of the comparisons indicate that approximate first-order predictions, using a single set of input parameters, are possible and can be used to aid practical hazard and risk assessment.

Rock Burst Monitoring by Integrated Microseismic and Electromagnetic Radiation Methods

NASA Astrophysics Data System (ADS)

Li, Xuelong; Wang, Enyuan; Li, Zhonghui; Liu, Zhentang; Song, Dazhao; Qiu, Liming

2016-11-01

For this study, microseismic (MS) and electromagnetic radiation (EMR) monitoring systems were installed in a coal mine to monitor rock bursts. The MS system monitors coal or rock mass ruptures in the whole mine, whereas the EMR equipment monitors the coal or rock stress in a small area. By analysing the MS energy, number of MS events, and EMR intensity with respect to rock bursts, it has been shown that the energy and number of MS events present a "quiet period" 1-3 days before the rock burst. The data also show that the EMR intensity reaches a peak before the rock burst and this EMR intensity peak generally corresponds to the MS "quiet period". There is a positive correlation between stress and EMR intensity. Buckling failure of coal or rock depends on the rheological properties and occurs after the peak stress in the high-stress concentration areas in deep mines. The MS "quiet period" before the rock burst is caused by the heterogeneity of the coal and rock structures, the transfer of high stress into internal areas, locked patches, and self-organized criticality near the stress peak. This study increases our understanding of coal and rock instability in deep mines. Combining MS and EMR to monitor rock burst could improve prediction accuracy.

Anomalous concentrations of seismically triggered rock falls in Pacoima Canyon: Are they caused by highly susceptible slopes or local amplification of seismic shaking?

USGS Publications Warehouse

Harp, Edwin L.; Jibson, Randall W.

2002-01-01

Anomalously high concentrations of rock falls were triggered in Pacoima Canyon (Los Angeles, California) during the 1994 Northridge earthquake. Similar concentrations were also documented from the 1971 San Fernando earthquake. Using an engineering rock-mass classification that evaluates the susceptibility of rock slopes to seismic failure based on the fracture properties of a rock mass (in terms of a numerical "Q-value" that describes rock quality), the rock slopes in Pacoima Canyon were compared with rock slopes in sorrounding areas where topography and lithology are similar, but rock-fall concentrations from the earthquakes were much lower. A statistical comparison of Q-values from five sites surrounding Pacoima Canyon indicates that seismic susceptibilities are similar to those within Pacoima Canyon; differences in the characteristics of rock slopes between these sites are not sufficient to account for the relatively high concentrations of rock falls within Pacoima Canyon as compared to low concentrations elsewhere. By eliminating susceptibility differences as a cause, the most likely explanations for the differences in rock-fall concentrations is anomalously high shaking levels in Pacoima Canyon, possibly resulting from topographic amplification within the canyon.

Landslides and rock fall processes in the proglacial area of the Gepatsch glacier, Tyrol, Austria - Quantitative assessment of controlling factors and process rates

NASA Astrophysics Data System (ADS)

Vehling, Lucas; Rohn, Joachim; Moser, Michael

2013-04-01

Due to the rapid deglaciation since 1850, lithological structures and topoclimatic factors, mass movements like rock fall, landslides and complex processes are important contributing factors to sediment transport and modification of the earth's surface in the steep, high mountain catchment of the Gepatsch reservoir. Contemporary geotechnical processes, mass movement deposits, their source areas, and controlling factors like material properties and relief parameters are mapped in the field, on Orthofotos and on digital elevation models. The results are presented in an Arc-Gis based geotechnical map. All mapped mass movements are stored in an Arc-Gis geodatabase and can be queried regarding properties, volume and controlling factors, so that statistical analyses can be conducted. The assessment of rock wall retreat rates is carried out by three different methods in multiple locations, which differ in altitude, exposition, lithology and deglaciation time: Firstly, rock fall processes and rates are investigated in detail on five rock fall collector nets with an overall size of 750 m2. Rock fall particles are gathered, weighed and grain size distribution is detected by sieving and measuring the diameter of the particles to distinct between rock fall processes and magnitudes. Rock wall erosion processes like joint formation and expansions are measured with high temporal resolution by electrical crack meters, together with rock- and air temperature. Secondly, in cooperation with the other working groups in the PROSA project, rock fall volumes are determined with multitemporal terrestrial laserscanning from several locations. Lately, already triggered rock falls are accounted by mapping the volume of the deposit and calculating of the bedrock source area. The deposition time span is fixed by consideration of the late Holocene lateral moraines and analysing historical aerial photographs, so that longer term rock wall retreat rates can be calculated. In order to limit

Recent advances in analysis and prediction of Rock Falls, Rock Slides, and Rock Avalanches using 3D point clouds

NASA Astrophysics Data System (ADS)

Abellan, A.; Carrea, D.; Jaboyedoff, M.; Riquelme, A.; Tomas, R.; Royan, M. J.; Vilaplana, J. M.; Gauvin, N.

2014-12-01

The acquisition of dense terrain information using well-established 3D techniques (e.g. LiDAR, photogrammetry) and the use of new mobile platforms (e.g. Unmanned Aerial Vehicles) together with the increasingly efficient post-processing workflows for image treatment (e.g. Structure From Motion) are opening up new possibilities for analysing, modeling and predicting rock slope failures. Examples of applications at different scales ranging from the monitoring of small changes at unprecedented level of detail (e.g. sub millimeter-scale deformation under lab-scale conditions) to the detection of slope deformation at regional scale. In this communication we will show the main accomplishments of the Swiss National Foundation project "Characterizing and analysing 3D temporal slope evolution" carried out at Risk Analysis group (Univ. of Lausanne) in close collaboration with the RISKNAT and INTERES groups (Univ. of Barcelona and Univ. of Alicante, respectively). We have recently developed a series of innovative approaches for rock slope analysis using 3D point clouds, some examples include: the development of semi-automatic methodologies for the identification and extraction of rock-slope features such as discontinuities, type of material, rockfalls occurrence and deformation. Moreover, we have been improving our knowledge in progressive rupture characterization thanks to several algorithms, some examples include the computing of 3D deformation, the use of filtering techniques on permanently based TLS, the use of rock slope failure analogies at different scales (laboratory simulations, monitoring at glacier's front, etc.), the modelling of the influence of external forces such as precipitation on the acceleration of the deformation rate, etc. We have also been interested on the analysis of rock slope deformation prior to the occurrence of fragmental rockfalls and the interaction of this deformation with the spatial location of future events. In spite of these recent advances

Demonstration of a Fractured Rock Geophysical Toolbox (FRGT) for Characterization and Monitoring of DNAPL Biodegradation in Fractured Rock Aquifers

DTIC Science & Technology

2016-01-01

USER’S GUIDE Demonstration of a Fractured Rock Geophysical Toolbox (FRGT) for Characterization and Monitoring of DNAPL Biodegradation in...Toolbox (FRGT) for Characterization and Monitoring of DNAPL Biodegradation in Fractured Rock Aquifers F.D. Day-Lewis, C.D. Johnson, J.H. Williams, C.L...are doomed to failure. DNAPL biodegradation charactrization and monitoring, remediation, fractured rock aquifers. Unclassified Unclassified UU UL 6

Active and passive seismic methods for characterization and monitoring of unstable rock masses: field surveys, laboratory tests and modeling.

NASA Astrophysics Data System (ADS)

Colombero, Chiara; Baillet, Laurent; Comina, Cesare; Jongmans, Denis; Vinciguerra, Sergio

2016-04-01

Appropriate characterization and monitoring of potentially unstable rock masses may provide a better knowledge of the active processes and help to forecast the evolution to failure. Among the available geophysical methods, active seismic surveys are often suitable to infer the internal structure and the fracturing conditions of the unstable body. For monitoring purposes, although remote-sensing techniques and in-situ geotechnical measurements are successfully tested on landslides, they may not be suitable to early forecast sudden rapid rockslides. Passive seismic monitoring can help for this purpose. Detection, classification and localization of microseismic events within the prone-to-fall rock mass can provide information about the incipient failure of internal rock bridges. Acceleration to failure can be detected from an increasing microseismic event rate. The latter can be compared with meteorological data to understand the external factors controlling stability. On the other hand, seismic noise recorded on prone-to-fall rock slopes shows that the temporal variations in spectral content and correlation of ambient vibrations can be related to both reversible and irreversible changes within the rock mass. We present the results of the active and passive seismic data acquired at the potentially unstable granitic cliff of Madonna del Sasso (NW Italy). Down-hole tests, surface refraction and cross-hole tomography were carried out for the characterization of the fracturing state of the site. Field surveys were implemented with laboratory determination of physico-mechanical properties on rock samples and measurements of the ultrasonic pulse velocity. This multi-scale approach led to a lithological interpretation of the seismic velocity field obtained at the site and to a systematic correlation of the measured velocities with physical properties (density and porosity) and macroscopic features of the granitic cliff (fracturing, weathering and anisotropy). Continuous

Rock-fall hazard in the Etruscan archaeological site of Norchia (Central Italy)

NASA Astrophysics Data System (ADS)

Margottini, Claudio; Spizzichino, Daniele; Argento, Alessia; Russo, Alfonsina

2016-04-01

have allowed the creation of a typical "butte" landscape, later inhabited by Etruscans, are still active. Field survey and historical data collection revealed the presence of many rock slope instabilities that have affected the site. Particularly meaningful is the presence of a large debris fan, just at the toe of the most relevant archaeological place, where the half-cube rock-cut tombs are positioned, testifying important rock-falls after the excavation of the necropolis. The preliminary investigation is revealing the importance of rock-fall hazard as well as the other environmental threats for the future conservation of the site. An integrated approach among different experts is now required, to define processes and causative factors and then to establish priorities for conservation

Prospective monitoring and self-report of previous falls among older women at high risk of falls and fractures: a study of comparison and agreement

PubMed Central

Garcia, Patrícia A.; Dias, João M. D.; Silva, Silvia L. A.; Dias, Rosângela C.

2015-01-01

Background: The identification of the occurrence of falls is an important step for screening and for rehabilitation processes for the elderly. The methods of monitoring these events are susceptible to recording biases, and the choice of the most accurate method remains challenging. Objectives: (i) To investigate the agreement between retrospective self-reporting and prospective monitoring of methods of recording falls, and (ii) to compare the retrospective self-reporting of falls and the prospective monitoring of falls and recurrent falls over a 12-month period among older women at high risk of falls and fractures. Method: A total of 118 community-dwelling older women with low bone density were recruited. The incidence of falls was monitored prospectively in 116 older women (2 losses) via monthly phone calls over the course of a year. At the end of this monitoring period, the older women were asked about their recall of falls in the same 12-month period. The agreement between the two methods was analyzed, and the sensitivity and specificity of self-reported previous falls in relation to the prospective monitoring were calculated. Results: There was moderate agreement between the prospective monitoring and the retrospective self-reporting of falls in classifying fallers (Kappa=0.595) and recurrent fallers (Kappa=0.589). The limits of agreement were 0.35±1.66 falls. The self-reporting of prior falls had a 67.2% sensitivity and a 94.2% specificity in classifying fallers among older women and a 50% sensitivity and a 98.9% specificity in classifying recurrent fallers. Conclusion: Self-reporting of falls over a 12-month period underestimated 32.8% of falls and 50% of recurrent falls. The findings recommend caution if one is considering replacing monthly monitoring with annual retrospective questioning. PMID:26083603

Dynamic characterization of the Chamousset rock column before its fall

NASA Astrophysics Data System (ADS)

Levy, C.; Baillet, L.; Jongmans, D.

2009-04-01

The rockfall of Chamousset (volume of 21000m3 ) occurred on November 10, 2007, affecting the 300 m high Urgonian cliff of the southern Vercors massif, French Alps. This event took place when the Vercors plateau was covered by snow. The unstable column was previously detected by observations on the development of a 30 m long fracture back on the plateau. Two aerial Lidar scans of the cliff were acquired before and after the failure, allowing the geometry of the column and of the broken plane to be determined. A temporary seismic array along with two extensometers was installed from July to November 2007. The seismic array consisted of 7 short period seismometers (1 three-components and 6 vertical-component). One vertical seismometer was installed on the column while the other 6 were deployed on the plateau with an array aperture of about 70 m. During the last two months of record, short period seismometers were replaced by 4.5 Hz geophones. The monitoring system recorded in a continuous mode (1000 Hz of frequency sampling) but it stopped to work two weeks before the fall, after the solar panels were covered by snow. During the running period, the seismic array recorded hundreds of local seismic events, from short (less than 0.5 s) impulsive signals to events with a long duration (a few tens of seconds). Our study was first focused on the dynamic response of the column and on the seismic noise frequency content. Fourier spectra of the seismic noise signals recorded on the column and the corresponding spectral ratios showed the presence of several resonance frequencies of the column. The first resonance frequency was measured at 3.6 Hz in July 2007 and it decreases regularly with time to reach 2.6 Hz two weeks before the fall. In parallel, extensometer measurements show that the fracture aperture increased with time during the same period. The dynamic response of a block which separates from a rock mass was 2D numerically modelled. Finite element computations showed

Seismic monitoring of the unstable rock slope at Aaknes, Norway

NASA Astrophysics Data System (ADS)

Roth, M.; Blikra, L. H.

2009-04-01

The unstable rock slope at Aaknes has an estimated volume of about 70 million cubic meters, and parts of the slope are moving at a rate between 2-15 cm/year. Amongst many other direct monitoring systems we have installed a small-scale seismic network (8 three-component geophones over an area of 250 x 150 meters) in order to monitor microseismic events related to the movement of the slope. The network has been operational since November 2005 with only a few short-term outages. Seismic data are transferred in real-time from the site to NORSAR for automatic detection processing. The resulting detection lists and charts and the associated waveform are forwarded immediately to the early warning centre of the Municipality of Stranda. Furthermore, we make them available after a delay of about 10-15 minutes on our public project web page (http://www.norsar.no/pc-47-48-Latest-Data.aspx). Seismic monitoring provides independent and complementary data to the more direct monitoring systems at Aaknes. We observe increased seismic activity in periods of heavy rain fall or snow melt, when laser ranging data and extensometer readings indicate temporary acceleration phases of the slope. The seismic network is too small and the velocity structure is too heterogeneous in order to obtain reliable localizations of the microseismic events. In summer 2009 we plan to install a high-sensitive broadband seismometer (60 s - 100 Hz) in the middle of the unstable slope. This will allow us to better constrain the locations of the microseismic events and to investigate potential low-frequency signals associated with the slope movement.

Rock Island Dam Smolt Monitoring; 1994-1995 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Truscott, Keith B.; Fielder, Paul C.

1995-10-01

Downstream migrating salmon and steelhead trout (Oncorhynchus spp.) smolts were monitored at the Rock Island Dam bypass trap from April 1 - August 31, 1954. This was the tenth consecutive year that the bypass trap was monitored. Data collected included: (1) number of fish caught by species, (2) number of adipose clipped and/or Passive Integrated Transponder (PIT) tagged fish caught by species, (3) daily average riverflow, (4) daily average powerhouse No. 1 and No. 2 flows and daily average spill. These data were transmitted to the Fish Passage Center, which manages the Smolt Monitoring Program throughout the Columbia River Basin.more » The Smolt Monitoring Program is used to manage the {open_quotes}water budget{close_quotes}, releasing upstream reservoir water storage allocated to supplement river flows to enhance survival of downstream migrating juvenile salmonids. The Rock Island Dam trapping facility collected 37,795 downstream migrating salmonids in 1994. Collected fish included 4 yearling and 4 sub-yearling chinook salmon (O. tshawytscha) that had been previously PIT tagged to help determine migration rates. Additionally, 1,132 sub-yearling chinook, 4,185 yearling chinook, 6,627 steelhead, (O. mykiss) and 422 sockeye (O. nerka) with clipped adipose fins were collected. The middle 80% of the 1994 spring migration (excluding sub-yearling chinooks) passed Rock Island Dam during a 34 day period, April 25 - May 28. Passage rates of chinook and steelhead smolts released from hatcheries and the downstream migration timing of all salmonids are presented. The spring migration timing of juvenile salmonids is strongly influenced by hatchery releases above Rock Island Dam.« less

Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks

PubMed Central

Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

2008-01-01

Reliable structural health monitoring (SHM) including nondestructive evaluation (NDE) is essential for safe operation of infrastructure systems. Effective monitoring of the rock components of civil infrastructures such as tunnels and caverns remains challenging. The feasibility of employing smart optical fibre sensor (OFS) and piezoelectric impedance sensor made up of lead zirconate titanate (PZT) for comprehensive health monitoring of rocks, covering load history monitoring/retrieval as well as damage assessment is presented in this paper. The rock specimens are subjected to cyclic loading and their conditions are continuously monitored using OFS and PZT sensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded on the rock specimens. Their strain sensing performance is compared with the conventional electric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimens to study the damage pattern during different loading cycles. Unlike the FBGs or ESGs, PZT patches are used as bi-functional sensors and actuators, enabling them to be efficient detectors of incipient damages using the principle of electromechanical impedance. The experimental study demonstrated superior performance of these smart FBG and PZT impedance sensors. This work is expected to be useful for SHM based NDE application of rock structures such as caverns and tunnels. PMID:27879708

Monitoring of Pre-Load on Rock Bolt Using Piezoceramic-Transducer Enabled Time Reversal Method.

PubMed

Huo, Linsheng; Wang, Bo; Chen, Dongdong; Song, Gangbing

2017-10-27

Rock bolts ensure structural stability for tunnels and many other underground structures. The pre-load on a rock bolt plays an important role in the structural reinforcement and it is vital to monitor the pre-load status of rock bolts. In this paper, a rock bolt pre-load monitoring method based on the piezoceramic enabled time reversal method is proposed. A lead zirconate titanate (PZT) patch transducer, which works as an actuator to generate stress waves, is bonded onto the anchor plate of the rock bolt. A smart washer, which is fabricated by sandwiching a PZT patch between two metal rings, is installed between the hex nut and the anchor plate along the rock bolt. The smart washer functions as a sensor to detect the stress wave. With the increase of the pre-load values on the rock bolt, the effective contact surface area between the smart washer and the anchor plate, benefiting the stress wave propagation crossing the contact surface. With the help of time reversal technique, experimental results reveal that the magnitude of focused signal clearly increases with the increase of the pre-load on a rock bolt before the saturation which happens beyond a relatively high value of the pre-load. The proposed method provides an innovative and real time means to monitor the pre-load level of a rock bolt. By employing this method, the pre-load degradation process on a rock bolt can be clearly monitored. Please note that, currently, the proposed method applies to only new rock bolts, on which it is possible to install the PZT smart washer.

Integrating GIS-based geologic mapping, LiDAR-based lineament analysis and site specific rock slope data to delineate a zone of existing and potential rock slope instability located along the grandfather mountain window-Linville Falls shear zone contact, Southern Appalachian Mountains, Watauga County, North Carolina

USGS Publications Warehouse

Gillon, K.A.; Wooten, R.M.; Latham, R.L.; Witt, A.W.; Douglas, T.J.; Bauer, J.B.; Fuemmeler, S.J.

2009-01-01

Landslide hazard maps of Watauga County identify >2200 landslides, model debris flow susceptibility, and evaluate a 14km x 0.5km zone of existing and potential rock slope instability (ZEPRSI) near the Town of Boone. The ZEPRSI encompasses west-northwest trending (WNWT) topographic ridges where 14 active/past-active rock/weathered rock slides occur mainly in rocks of the Grandfather Mountain Window (GMW). The north side of this ridgeline is the GMW / Linville Falls Fault (LFF) contact. Sheared rocks of the Linville Falls Shear Zone (LFSZ) occur along the ridge and locally in the valley north of the contact. The valley is underlain principally by layered granitic gneiss comprising the Linville Falls/Beech Mountain/Stone Mountain Thrust Sheet. The integration of ArcGIS??? - format digital geologic and lineament mapping on a 6m LiDAR (Light Detecting and Ranging) digital elevation model (DEM) base, and kinematic analyses of site specific rock slope data (e.g., presence and degree of ductile and brittle deformation fabrics, rock type, rock weathering state) indicate: WNWT lineaments are expressions of a regionally extensive zone of fractures and faults; and ZEPRSI rock slope failures concentrate along excavated, north-facing LFF/LFSZ slopes where brittle fabrics overprint older metamorphic foliations, and other fractures create side and back release surfaces. Copyright 2009 ARMA, American Rock Mechanics Association.

Fall prevention and monitoring of assisted living patients: an exploratory study of physician perspectives.

PubMed

Nyrop, Kirsten A; Zimmerman, Sheryl; Sloane, Philip D; Bangdiwala, Srikant

2012-06-01

Explore physician perspectives on their involvement in fall prevention and monitoring for residential care/assisted living (RC/AL) residents. Exploratory cross-sectional study; mailed questionnaire. Four RC/AL communities, North Carolina. Primary physicians for RC/AL residents. Past Behavior and future Intentions of physicians with regard to (1) fall risk assessment and (2) collaboration with RC/AL staff to reduce falls and fall risks among RC/AL residents were explored using Theory of Planned Behavior (TPB) constructs. Predictor variables examined (1) physicians' views on their own responsibilities (Attitude), (2) their views of expectations from important referent groups (Subjective Norms), and (3) perceived constraints on engaging in fall prevention and monitoring (Perceived Behavioral Control). Physicians reported conducting fall risk assessments of 47% of RC/AL patients and collaborating with RC/AL staff to reduce fall risks for 36% of RC/AL patients (Behavior). These proportions increased to 75% and 62%, respectively, for future Intentions. TPB-based models explained approximately 60% of the variance in self-reported Behavior and Intentions. Physician's involvement in fall prevention and monitoring was significantly associated (P < .05) with their perceptions of barriers and facilitators-ease, time, reimbursement, and expertise. This study provides first data on physician beliefs regarding their involvement in fall risk assessment of RC/AL patients and collaboration with RC/AL staff to reduce fall risks of individual patients. Challenges to physician involvement identified in our study are not unique or specific to the RC/AL setting, and instead relate to clinical practice and reimbursement constraints in general. Copyright © 2012 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Landscape development in an hyperarid sandstone environment along the margins of the Dead Sea fault: Implications from dated rock falls

USGS Publications Warehouse

Matmon, A.; Shaked, Y.; Porat, N.; Enzel, Y.; Finkel, R.; Lifton, N.; Boaretto, E.; Agnon, A.

2005-01-01

In this study, we explored the spatial and temporal relations between boulders and their original in-situ locations on sandstone bedrock cliffs. This was accomplished by combining field observations with dating methods using cosmogenic isotopes (10Be and 14C) and optically stimulated luminescence (OSL). Our conclusions bear both on the landscape evolution and cliff retreat process in the hyperarid region of Timna and on the methodology of estimating exposure ages using cosmogenic isotopes. We recognize three discrete rock fall events, at 31 ka, 15 ka, and 4 ka. In this hyperarid region, the most plausible triggering mechanism for rock fall events is strong ground acceleration caused by earthquakes generated by the nearby Dead Sea fault (DSF). Our record, however, under represents the regional earthquake record implying that ongoing development of detachment cracks prior to the triggering event might be slower than the earthquake cycle. Cliff retreat rates calculated using the timing of rock fall events and estimated thickness of rock removed in each event range between 0.14 m ky-1 and 2 m ky-1. When only full cycles are considered, we derive a more realistic range of 0.4 m ky-1 to 0.7 m ky-1. These rates are an order of magnitude faster than the calculated rate of surface lowering in the area. We conclude that sandstone cliffs at Timna retreat through episodic rock fall events that preserve the sharp, imposing, landscape characteristic to this region and that ongoing weathering of the cliff faces is minor. A 10%-20% difference in the 10Be concentrations in samples from matching boulder and cliff faces that have identical exposure histories and are located only a few meters apart indicates that cosmogenic nuclide production rates are sensitive to shielding and vary spatially over short distances. However, uncertainties associated with age calculations yielded boulder and matching cliff face ages that are similar within 1 ??. The use of external constraints in the

Rock Slide Monitoring by Using TDR Inclinometers

NASA Astrophysics Data System (ADS)

Drusa, Marián; Bulko, Roman

2016-12-01

The geotechnical monitoring of the slope deformations is widespread at present time. In many geological localities and civil engineering construction areas, monitoring is a unique tool for controlling of negative factors and processes, also inform us about actual state of rock environment or interacting structures. It is necessary for risk assessment. In our case, geotechnical monitoring is controlling rockslide activity around in the future part of motorway. The construction of new highway route D1 from Bratislava to Košice crosses the territory which is affected by a massive rockslide close to Kraľovany village. There was a need to monitor the activity of a large unstable rockslide with deep shear planes. In this case of underground movement activity, the Department of Geotechnics of the University of Žilina installed inclinometers at the unstable area which worked on Time Domain Reflectometry (TDR) principle. Based on provided measurements, effectivity and suitability of TDR inclinometers for monitoring of deep underground movement activity is demonstrated.

Monitoring of bedridden patients: development of a fall detection tool.

PubMed

Vilas-Boas, M; Silva, P; Cunha, S R; Correia, M V

2013-01-01

Falls of patients are an important issue in hospitals nowadays; it causes severe injuries, increases hospitalization time and treatment costs. The detection of a fall, in time, provides faster rescue to the patient, preventing more serious injuries, as well as saving nursing time. The MovinSense® is an electronic device designed for monitoring patients to prevent pressure sores, and the main goal of this work was to develop a new tool for this device, with the purpose of detecting if the patient has fallen from the hospital bed, without changing any of the device's original features. Experiments for gathering data samples of inertial signals of falling from the bed were obtained using the device. For fall detection a sensitivity of 72% and specificity of 100% were reached. Another algorithm was developed to detect if the patient got out of his/her bed.

Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks.

PubMed

Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

2008-01-21

Reliable structural health monitoring (SHM) including nondestructiveevaluation (NDE) is essential for safe operation of infrastructure systems. Effectivemonitoring of the rock components of civil infrastructures such as tunnels and cavernsremains challenging. The feasibility of employing smart optical fibre sensor (OFS) andpiezoelectric impedance sensor made up of lead zirconate titanate (PZT) forcomprehensive health monitoring of rocks, covering load history monitoring/retrieval aswell as damage assessment is presented in this paper. The rock specimens are subjected tocyclic loading and their conditions are continuously monitored using OFS and PZTsensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded onthe rock specimens. Their strain sensing performance is compared with the conventionalelectric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimensto study the damage pattern during different loading cycles. Unlike the FBGs or ESGs,PZT patches are used as bi-functional sensors and actuators, enabling them to be efficientdetectors of incipient damages using the principle of electromechanical impedance. Theexperimental study demonstrated superior performance of these smart FBG and PZTimpedance sensors. This work is expected to be useful for SHM based NDE application ofrock structures such as caverns and tunnels.

RockFall analyst: A GIS extension for three-dimensional and spatially distributed rockfall hazard modeling

NASA Astrophysics Data System (ADS)

Lan, Hengxing; Derek Martin, C.; Lim, C. H.

2007-02-01

Geographic information system (GIS) modeling is used in combination with three-dimensional (3D) rockfall process modeling to assess rockfall hazards. A GIS extension, RockFall Analyst (RA), which is capable of effectively handling large amounts of geospatial information relative to rockfall behaviors, has been developed in ArcGIS using ArcObjects and C#. The 3D rockfall model considers dynamic processes on a cell plane basis. It uses inputs of distributed parameters in terms of raster and polygon features created in GIS. Two major components are included in RA: particle-based rockfall process modeling and geostatistics-based rockfall raster modeling. Rockfall process simulation results, 3D rockfall trajectories and their velocity features either for point seeders or polyline seeders are stored in 3D shape files. Distributed raster modeling, based on 3D rockfall trajectories and a spatial geostatistical technique, represents the distribution of spatial frequency, the flying and/or bouncing height, and the kinetic energy of falling rocks. A distribution of rockfall hazard can be created by taking these rockfall characteristics into account. A barrier analysis tool is also provided in RA to aid barrier design. An application of these modeling techniques to a case study is provided. The RA has been tested in ArcGIS 8.2, 8.3, 9.0 and 9.1.

Interesting insights into instability of slopes and rock fall in the morphodynamic Himalayan terrane

NASA Astrophysics Data System (ADS)

Singh, T. N.; Vishal, V.; Pradhan, S. P.

2015-12-01

Himalayan mountain ranges are tectonically and seismically very active and experience many disastrous events with time due to slope failure. Frequent failures of rock cut slopes cause obstruction in traffic and often lead to fatalities. In recent years, the number of tragedies has increased when associated with regional phenomena such at the Kedarnath tragedy of 2013 and the Gorkha earthquake of 2015. The influence of such phenomena on the stability of slopes along important national highways and key settlement areas only raise the risk to lives and property. We conducted a multi-approach investigation for some key slopes along the National Highway 58 in Uttarakhand Himalaya, India. A very detailed field work was conducted to identify the unstable slopes and those with some history of failure. The pertinent geomechanical characteristics of the representative rock samples were determined in the laboratory. Based on the structural data, kinematic analysis was carried out. Finally the slopes were simulated using FDM based simulator, Flac/Slope for analysing the health of the slopes and Rockfall 4.0 to investigate the phenomenon of rockfall along the Highway. It was found that few slopes were weak due to the inherent weak rock materials while few slopes made up of high strength rocks were effectively weak due to prone-to-failure orientation of the joints. Quantification of bounce-height of rock blocks during fall, their energy, velocity and displacement along the slope was also done. Using 3-D simulations, few critically-stable slopes that appear to be stable, were identified. Little ground movement could be capable of triggering a large scale failure in the area. Slopes in the studied region are under threat to failure and need immediate proper planning using the suggested remedial measures.

An overview of geophysical technologies appropriate for characterization and monitoring at fractured-rock sites

EPA Science Inventory

Geophysical methods are used increasingly for characterization and monitoring at remediation sites in fractured-rock aquifers. The complex heterogeneity of fractured rock poses enormous challenges to groundwater remediation professionals, and new methods are needed to cost-effect...

Development of novel algorithm and real-time monitoring ambulatory system using Bluetooth module for fall detection in the elderly.

PubMed

Hwang, J Y; Kang, J M; Jang, Y W; Kim, H

2004-01-01

Novel algorithm and real-time ambulatory monitoring system for fall detection in elderly people is described. Our system is comprised of accelerometer, tilt sensor and gyroscope. For real-time monitoring, we used Bluetooth. Accelerometer measures kinetic force, tilt sensor and gyroscope estimates body posture. Also, we suggested algorithm using signals which obtained from the system attached to the chest for fall detection. To evaluate our system and algorithm, we experimented on three people aged over 26 years. The experiment of four cases such as forward fall, backward fall, side fall and sit-stand was repeated ten times and the experiment in daily life activity was performed one time to each subject. These experiments showed that our system and algorithm could distinguish between falling and daily life activity. Moreover, the accuracy of fall detection is 96.7%. Our system is especially adapted for long-time and real-time ambulatory monitoring of elderly people in emergency situation.

Long term monitoring of rock surface temperature and rock cracking in temperate and desert climates

NASA Astrophysics Data System (ADS)

Eppes, M. C.; Warren, K.; Hinson, E.; Dash, L.

2012-12-01

The extent to which diurnal cycling of temperature results in the mechanical breakdown of rock cannot be clearly defined until direct connections between rock surface temperatures and rock cracking are identified under natural conditions. With this goal, we have developed a unique instrumentation system for monitoring spatial (N-, S-, E-, W-, up- and down-facing) and temporal (per minute) temperature variability in natural boulders while simultaneously monitoring cracking via acoustic emission sensors. To date, we have collected 11 and 12 months of data respectively for ~30 cm diameter granite boulders placed in North Carolina (near Charlotte) and New Mexico (Sevilleta National Wildlife Refuge). These data allow us 1) to compare and contrast spatial and temporal trends in surface temperatures of natural boulders at high temporal resolution over unprecedentedly long time scales in two contrasting environments and 2) to make direct correlations between boulder surface temperatures and periods of microcracking as recorded by acoustic emissions in both environments. Preliminary analysis of both data sets indicates that there is no obvious single high or low threshold in surface temperature or rate of surface temperature change (measurable at a per minute scale) beyond which cracking occurs for either locality. For example, for the New Mexico rock, overall rock surface temperatures ranged from -27 C to 54 C throughout the year, and rock surface temperatures during the times of peak cracking event clusters ranged from -14 C to 46 C. The majority of events occur during winter months in North Carolina and in summer in New Mexico. The majority of events occurred in the late afternoon/early evening for both localities, although the overall numbers of cracking events was significantly higher in the New Mexico locality. In both cases, the key temperature factor that appears to most often correlate with cracking is the rate of change of temperature difference across the rock

iFall: an Android application for fall monitoring and response.

PubMed

Sposaro, Frank; Tyson, Gary

2009-01-01

Injuries due to falls are among the leading causes of hospitalization in elderly persons, often resulting in a rapid decline in quality of life or death. Rapid response can improve the patients outcome, but this is often lacking when the injured person lives alone and the nature of the injury complicates calling for help. This paper presents an alert system for fall detection using common commercially available electronic devices to both detect the fall and alert authorities. We use an Android-based smart phone with an integrated tri-axial accelerometer. Data from the accelerometer is evaluated with several threshold based algorithms and position data to determine a fall. The threshold is adaptive based on user provided parameters such as: height, weight, and level of activity. The algorithm adapts to unique movements that a phone experiences as opposed to similar systems which require users to mount accelerometers to their chest or trunk. If a fall is suspected a notification is raised requiring the user's response. If the user does not respond, the system alerts pre-specified social contacts with an informational message via SMS. If a contact responds the system commits an audible notification, automatically connects, and enables the speakerphone. If a social contact confirms a fall, an appropriate emergency service is alerted. Our system provides a realizable, cost effective solution to fall detection using a simple graphical interface while not overwhelming the user with uncomfortable sensors.

Concept of Complex Environmental Monitoring Network - Vardzia Rock Cut City Case Study

NASA Astrophysics Data System (ADS)

Elashvili, Mikheil; Vacheishvili, Nikoloz; Margottini, Claudio; Basilaia, Giorgi; Chkhaidze, Davit; Kvavadze, Davit; Spizzichino, Daniele; Boscagli, Franceso; Kirkitadze, Giorgi; Adikashvili, Luka; Navrozashvili, Levan

2016-04-01

Vardzia represents an unique cultural heritage monument - rock cut city, which unites architectural monument and Natural-Geological complex. Such monuments are particularly vulnerable and their restoration and conservation requires complex approach. It is curved in various layers of volcanic tuffs and covers several hectares of area, with chronologically different segments of construction. This monument, as many similar monuments worldwide, is subjected to slow but permanent process of destruction, expressed in following factors: surface weathering of rock, active tectonics (aseismic displacement along the active faults and earthquakes), interaction between lithologically different rock layers, existence of major cracks and associated complex block structure, surface rainwater runoff and infiltrated ground water, temperature variations, etc. During its lifetime, Vardzia was heavily damaged by Historical Earthquake of 1283 and only partly restored afterwards. The technological progress together with the increased knowledge about ongoing environmental processes, established the common understanding that the complex monitoring of the environment represents the essential component for resolving such a principal issues, as: Proper management and prevention of natural disasters; Modeling of environmental processes, their short and long term prognosis; Monitoring of macro and micro climate; Safe functioning and preservation of important constructions. Research Center of Cultural Heritage and Environment of Ilia State University in cooperation with Experts from ISPRA, with the funding from the State agency of Cultural Heritage, has developed a concept of Vardzia complex monitoring network. Concept of the network includes: monitoring local meteorological conditions (meteorological station), monitoring microclimate in caves (temperature and humidity in the air and rock), monitoring microtremors and ambient seismic noise in Vardzia (local strong motion network), monitoring

Implementation of accelerometer sensor module and fall detection monitoring system based on wireless sensor network.

PubMed

Lee, Youngbum; Kim, Jinkwon; Son, Muntak; Lee, Myoungho

2007-01-01

This research implements wireless accelerometer sensor module and algorithm to determine wearer's posture, activity and fall. Wireless accelerometer sensor module uses ADXL202, 2-axis accelerometer sensor (Analog Device). And using wireless RF module, this module measures accelerometer signal and shows the signal at ;Acceloger' viewer program in PC. ADL algorithm determines posture, activity and fall that activity is determined by AC component of accelerometer signal and posture is determined by DC component of accelerometer signal. Those activity and posture include standing, sitting, lying, walking, running, etc. By the experiment for 30 subjects, the performance of implemented algorithm was assessed, and detection rate for postures, motions and subjects was calculated. Lastly, using wireless sensor network in experimental space, subject's postures, motions and fall monitoring system was implemented. By the simulation experiment for 30 subjects, 4 kinds of activity, 3 times, fall detection rate was calculated. In conclusion, this system can be application to patients and elders for activity monitoring and fall detection and also sports athletes' exercise measurement and pattern analysis. And it can be expected to common person's exercise training and just plaything for entertainment.

Evaluation of Feature Extraction and Recognition for Activity Monitoring and Fall Detection Based on Wearable sEMG Sensors.

PubMed

Xi, Xugang; Tang, Minyan; Miran, Seyed M; Luo, Zhizeng

2017-05-27

As an essential subfield of context awareness, activity awareness, especially daily activity monitoring and fall detection, plays a significant role for elderly or frail people who need assistance in their daily activities. This study investigates the feature extraction and pattern recognition of surface electromyography (sEMG), with the purpose of determining the best features and classifiers of sEMG for daily living activities monitoring and fall detection. This is done by a serial of experiments. In the experiments, four channels of sEMG signal from wireless, wearable sensors located on lower limbs are recorded from three subjects while they perform seven activities of daily living (ADL). A simulated trip fall scenario is also considered with a custom-made device attached to the ankle. With this experimental setting, 15 feature extraction methods of sEMG, including time, frequency, time/frequency domain and entropy, are analyzed based on class separability and calculation complexity, and five classification methods, each with 15 features, are estimated with respect to the accuracy rate of recognition and calculation complexity for activity monitoring and fall detection. It is shown that a high accuracy rate of recognition and a minimal calculation time for daily activity monitoring and fall detection can be achieved in the current experimental setting. Specifically, the Wilson Amplitude (WAMP) feature performs the best, and the classifier Gaussian Kernel Support Vector Machine (GK-SVM) with Permutation Entropy (PE) or WAMP results in the highest accuracy for activity monitoring with recognition rates of 97.35% and 96.43%. For fall detection, the classifier Fuzzy Min-Max Neural Network (FMMNN) has the best sensitivity and specificity at the cost of the longest calculation time, while the classifier Gaussian Kernel Fisher Linear Discriminant Analysis (GK-FDA) with the feature WAMP guarantees a high sensitivity (98.70%) and specificity (98.59%) with a short

Evaluation of Feature Extraction and Recognition for Activity Monitoring and Fall Detection Based on Wearable sEMG Sensors

PubMed Central

Xi, Xugang; Tang, Minyan; Miran, Seyed M.; Luo, Zhizeng

2017-01-01

As an essential subfield of context awareness, activity awareness, especially daily activity monitoring and fall detection, plays a significant role for elderly or frail people who need assistance in their daily activities. This study investigates the feature extraction and pattern recognition of surface electromyography (sEMG), with the purpose of determining the best features and classifiers of sEMG for daily living activities monitoring and fall detection. This is done by a serial of experiments. In the experiments, four channels of sEMG signal from wireless, wearable sensors located on lower limbs are recorded from three subjects while they perform seven activities of daily living (ADL). A simulated trip fall scenario is also considered with a custom-made device attached to the ankle. With this experimental setting, 15 feature extraction methods of sEMG, including time, frequency, time/frequency domain and entropy, are analyzed based on class separability and calculation complexity, and five classification methods, each with 15 features, are estimated with respect to the accuracy rate of recognition and calculation complexity for activity monitoring and fall detection. It is shown that a high accuracy rate of recognition and a minimal calculation time for daily activity monitoring and fall detection can be achieved in the current experimental setting. Specifically, the Wilson Amplitude (WAMP) feature performs the best, and the classifier Gaussian Kernel Support Vector Machine (GK-SVM) with Permutation Entropy (PE) or WAMP results in the highest accuracy for activity monitoring with recognition rates of 97.35% and 96.43%. For fall detection, the classifier Fuzzy Min-Max Neural Network (FMMNN) has the best sensitivity and specificity at the cost of the longest calculation time, while the classifier Gaussian Kernel Fisher Linear Discriminant Analysis (GK-FDA) with the feature WAMP guarantees a high sensitivity (98.70%) and specificity (98.59%) with a short

A miniature, wearable activity/fall monitor to assess the efficacy of mobility therapy for children with cerebral palsy during everyday living.

PubMed

Smith, Warren D; Bagley, Anita

2010-01-01

Children with cerebral palsy may have difficulty walking and may fall frequently, resulting in a decrease in their participation in school and community activities. It is desirable to assess the effectiveness of mobility therapies for these children on their functioning during everyday living. Over 50 hours of tri-axial accelerometer and digital video recordings from 35 children with cerebral palsy and 51 typically-developing children were analyzed to develop algorithms for automatic real-time processing of the accelerometer signals to monitor a child's level of activity and to detect falls. The present fall-detection algorithm has 100% specificity and a sensitivity of 100% for falls involving trunk rotation. Sensitivities for drops to the knees and to the bottom are 72% and 78%, respectively. The activity and fall-detection algorithms were implemented in a miniature, battery-powered microcontroller-based activity/fall monitor that the child wears in a small fanny pack during everyday living. The monitor continuously logs 1-min. activity levels and the occurrence and characteristics of each fall for two-week recording sessions. Pre-therapy and post-therapy recordings from these monitors will be used to assess the efficacies of alternative treatments for gait abnormalities.

Dance! Don't Fall - preventing falls and promoting exercise at home.

PubMed

Kerwin, Maureen; Nunes, Francisco; Silva, Paula Alexandra

2012-01-01

Falling is a serious danger to older adults that is usually only addressed after a person has fallen, when doctors administer clinical tests to determine the patient's risk of falling again. Having the technological capability of performing fall risk assessment tests with a smartphone, the authors set out to design a mobile application that would enable users to monitor their risk themselves and consequently prevent falls from occurring. The authors conducted a literature review and two observation sessions before beginning the iterative design process that resulted in the Dance! Don't Fall (DDF) game, a mobile application that enables users to both monitor their fall risk and actively reduce it through fun and easy exercise.

Ferguson rock slide buries California State Highway near Yosemite National Park

USGS Publications Warehouse

Harp, E.L.; Reid, M.E.; Godt, J.W.; DeGraff, J.V.; Gallegos, A.J.

2008-01-01

During spring 2006, talus from the toe area of a rock-block slide of about 800,000 m3 buried California State Highway 140, one of the main routes into heavily-visited Yosemite National Park, USA. Closure of the highway for 92 days caused business losses of about 4.8 million USD. The rock slide, composed of slate and phyllite, moved slowly downslope from April to June 2006, creating a fresh head scarp with 9-12 m of displacement. Movement of the main rock slide, a re-activation of an older slide, was triggered by an exceptionally wet spring 2006, following a very wet spring 2005. As of autumn 2006, most of the main slide appeared to be at rest, although rocks occasionally continued to fall from steep, fractured rock masses at the toe area of the slide. Future behavior of the slide is difficult to predict, but possible scenarios range from continued scattered rock fall to complete rapid failure of the entire mass. Although unlikely except under very destabilizing circumstances, a worst-case, rapid failure of the entire rock slide could extend across the Merced River, damming the river and creating a reservoir. As a temporary measure, traffic has been rerouted to the opposite side of the Merced River at about the same elevation as the buried section of Highway 140. A state-of-the-art monitoring system has been installed to detect movement in the steep talus slope, movement of the main slide mass, local strong ground motion from regional earthquakes, and sudden changes in stream levels, possibly indicating damming of the river by slide material. ?? 2008 Springer-Verlag.

Ferguson rock slide buries California State Highway near Yosemite National Park

USGS Publications Warehouse

Harp, Edwin L.; Reid, Mark E.; Godt, Jonathan W.; DeGraff, Jerome V.; Gallegos, Alan J.

2008-01-01

During spring 2006, talus from the toe area of a rock-block slide of about 800,000 m3 buried California State Highway 140, one of the main routes into heavily-visited Yosemite National Park, USA. Closure of the highway for 92 days caused business losses of about 4.8 million USD. The rock slide, composed of slate and phyllite, moved slowly downslope from April to June 2006, creating a fresh head scarp with 9-12 m of displacement. Movement of the main rock slide, a re-activation of an older slide, was triggered by an exceptionally wet spring 2006, following a very wet spring 2005. As of autumn 2006, most of the main slide appeared to be at rest, although rocks occasionally continued to fall from steep, fractured rock masses at the toe area of the slide. Future behavior of the slide is difficult to predict, but possible scenarios range from continued scattered rock fall to complete rapid failure of the entire mass. Although unlikely except under very destabilizing circumstances, a worst-case, rapid failure of the entire rock slide could extend across the Merced River, damming the river and creating a reservoir. As a temporary measure, traffic has been rerouted to the opposite side of the Merced River at about the same elevation as the buried section of Highway 140. A state-of-the-art monitoring system has been installed to detect movement in the steep talus slope, movement of the main slide mass, local strong ground motion from regional earthquakes, and sudden changes in stream levels, possibly indicating damming of the river by slide material.

ANALYSIS OF LABOUR ACCIDENTS DUE TO ROCK FALL EVENTS IN CUTTING FACE OF TUNNEL AND STUDY OF THE COUNTERMEASURES FOR SAFETY

NASA Astrophysics Data System (ADS)

Kikkawa, Naotaka; Itoh, Kazuya; Hori, Tomohito; Tamate, Satoshi; Toyosawa, Yasuo

In this paper, we analysed the labour accidents which had casualties due to rock fall events in the headings of tunnel and cleared the condition of the occurrence. It was clearly revealed that the accidents mostly happened when the workers mounted the explosive and the steel arch in the headings of the mountain tunnel. In addition, the dimension of the rocks fallen were averagely 0.6m diameter, it was not so much large. Therefore, the countermeasures based on both soft and hard faces would be useful and effective, such as the displacement measurement of a cutting face of tunnel, securing the sufficient lights to observe the cutting face, boring for drainage and shotcreting in a heading of tunnel.

Older adults' perceptions of technologies aimed at falls prevention, detection or monitoring: a systematic review.

PubMed

Hawley-Hague, Helen; Boulton, Elisabeth; Hall, Alex; Pfeiffer, Klaus; Todd, Chris

2014-06-01

Over recent years a number of Information and Communication Technologies (ICTs) have emerged aiming at falls prevention, falls detection and alarms for use in case of fall. There are also a range of ICT interventions, which have been created or adapted to be pro-active in preventing falls, such as those which provide strength and balance training to older adults in the prevention of falls. However, there are issues related to the adoption and continued use of these technologies by older adults. This review provides an overview of older adults' perceptions of falls technologies. We undertook systematic searches of MEDLINE, EMBASE, CINAHL and PsychINFO, COMPENDEX and the Cochrane database. Key search terms included 'older adults', 'seniors', 'preference', 'attitudes' and a wide range of technologies, they also included the key word 'fall*'. We considered all studies that included older adults aged 50 and above. Studies had to include technologies related specifically to falls prevention, detection or monitoring. The Joanna Briggs Institute (JBI) tool and the Quality Assessment Tool for Quantitative Studies by the Effective Public Health Practice Project (EPHPP) were used. We identified 76 potentially relevant papers. Some 21 studies were considered for quality review. Twelve qualitative studies, three quantitative studies and 6 mixed methods studies were included. The literature related to technologies aimed at predicting, monitoring and preventing falls suggest that intrinsic factors related to older adults' attitudes around control, independence and perceived need/requirements for safety are important for their motivation to use and continue using technologies. Extrinsic factors such as usability, feedback gained and costs are important elements which support these attitudes and perceptions. Positive messages about the benefits of falls technologies for promoting healthy active ageing and independence are critical, as is ensuring that the technologies are simple

Smart Rocks for Bridge Scour Monitoring: Design and Localization Using Electromagnetic Techniques and Embedded Orientation Sensors

NASA Astrophysics Data System (ADS)

Radchenko, Andro

River bridge scour is an erosion process in which flowing water removes sediment materials (such as sand, rocks) from a bridge foundation, river beds and banks. As a result, the level of the river bed near a bridge pier is lowering such that the bridge foundation stability can be compromised, and the bridge can collapse. The scour is a dynamic process, which can accelerate rapidly during a flood event. Thus, regular monitoring of the scour progress is necessary to be performed at most river bridges. Present techniques are usually expensive, require large man/hour efforts, and often lack the real-time monitoring capabilities. In this dissertation a new method--'Smart Rocks Network for bridge scour monitoring' is introduced. The method is based on distributed wireless sensors embedded in ground underwater nearby the bridge pillars. The sensor nodes are unconstrained in movement, are equipped with years-lasting batteries and intelligent custom designed electronics, which minimizes power consumption during operation and communication. The electronic part consists of a microcontroller, communication interfaces, orientation and environment sensors (such as are accelerometer, magnetometer, temperature and pressure sensors), supporting power supplies and circuitries. Embedded in the soil nearby a bridge pillar the Smart Rocks can move/drift together with the sediments, and act as the free agent probes transmitting the unique signature signals to the base-station monitors. Individual movement of a Smart Rock can be remotely detected processing the orientation sensors reading. This can give an indication of the on-going scour progress, and set a flag for the on-site inspection. The map of the deployed Smart Rocks Network can be obtained utilizing the custom developed in-network communication protocol with signals intensity (RSSI) analysis. Particle Swarm Optimization (PSO) is applied for map reconstruction. Analysis of the map can provide detailed insight into the scour

189. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

189. Photocopy of drawing, Twin Falls Canal Company, date unknown. ROCK CREEK CROSSING, LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, Photographer, date unknown. BLASTING TWIN FALLS CANAL, TWIN FALLS COUNTY; BLASTING COTTONWOOD AREA TO REPLACE FLUME BY RUNNING HIGH LINE THROUGH SOLID ROCK. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Effect of Hydrothermal Alteration on Rock Properties in Active Geothermal Setting

NASA Astrophysics Data System (ADS)

Mikisek, P.; Bignall, G.; Sepulveda, F.; Sass, I.

2012-04-01

Hydrothermal alteration records the physical-chemical changes of rock and mineral phases caused by the interaction of hot fluids and wall rock, which can impact effective permeability, porosity, thermal parameters, rock strength and other rock properties. In this project, an experimental approach has been used to investigate the effects of hydrothermal alteration on rock properties. A rock property database of contrastingly altered rock types and intensities has been established. The database details horizontal and vertical permeability, porosity, density, thermal conductivity and thermal heat capacity for ~300 drill core samples from wells THM12, THM13, THM14, THM17, THM18, THM22 and TH18 in the Wairakei-Tauhara geothermal system (New Zealand), which has been compared with observed hydrothermal alteration type, rank and intensity obtained from XRD analysis and optical microscopy. Samples were selected from clay-altered tuff and intercalated siltstones of the Huka Falls Formation, which acts as a cap rock at Wairakei-Tauhara, and tuffaceous sandstones of the Waiora Formation, which is a primary reservoir-hosting unit for lateral and vertical fluid flows in the geothermal system. The Huka Falls Formation exhibits argillic-type alteration of varying intensity, while underlying Waiora Formations exhibits argillic- and propylithic-type alteration. We plan to use a tempered triaxial test cell at hydrothermal temperatures (up to 200°C) and pressures typical of geothermal conditions, to simulate hot (thermal) fluid percolation through the rock matrix of an inferred "reservoir". Compressibility data will be obtained under a range of operating (simulation reservoir) conditions, in a series of multiple week to month-long experiments that will monitor change in permeability and rock strength accompanying advancing hydrothermal alteration intensity caused by the hot brine interacting with the rock matrix. We suggest, our work will provide new baseline information concerning

Stress-Induced Fracturing of Reservoir Rocks: Acoustic Monitoring and μCT Image Analysis

NASA Astrophysics Data System (ADS)

Pradhan, Srutarshi; Stroisz, Anna M.; Fjær, Erling; Stenebråten, Jørn F.; Lund, Hans K.; Sønstebø, Eyvind F.

2015-11-01

Stress-induced fracturing in reservoir rocks is an important issue for the petroleum industry. While productivity can be enhanced by a controlled fracturing operation, it can trigger borehole instability problems by reactivating existing fractures/faults in a reservoir. However, safe fracturing can improve the quality of operations during CO2 storage, geothermal installation and gas production at and from the reservoir rocks. Therefore, understanding the fracturing behavior of different types of reservoir rocks is a basic need for planning field operations toward these activities. In our study, stress-induced fracturing of rock samples has been monitored by acoustic emission (AE) and post-experiment computer tomography (CT) scans. We have used hollow cylinder cores of sandstones and chalks, which are representatives of reservoir rocks. The fracture-triggering stress has been measured for different rocks and compared with theoretical estimates. The population of AE events shows the location of main fracture arms which is in a good agreement with post-test CT image analysis, and the fracture patterns inside the samples are visualized through 3D image reconstructions. The amplitudes and energies of acoustic events clearly indicate initiation and propagation of the main fractures. Time evolution of the radial strain measured in the fracturing tests will later be compared to model predictions of fracture size.

Smart rock technology for real-time monitoring of bridge scour and riprap effectiveness - design guidelines and visualization tool.

DOT National Transportation Integrated Search

2016-12-31

This study aims to further develop and demonstrate the recently-proposed smart rock technology for : scour depth and protection effectiveness monitoring. A smart rock is one or two stacked magnets encased : in a concrete sphere with a specially-desig...

Monitoring of rock glacier dynamics by multi-temporal UAV images

NASA Astrophysics Data System (ADS)

Morra di Cella, Umberto; Pogliotti, Paolo; Diotri, Fabrizio; Cremonese, Edoardo; Filippa, Gianluca; Galvagno, Marta

2015-04-01

During the last years several steps forward have been made in the comprehension of rock glaciers dynamics mainly for their potential evolution into rapid mass movements phenomena. Monitoring the surface movement of creeping mountain permafrost is important for understanding the potential effect of ongoing climate change on such a landforms. This study presents the reconstruction of two years of surface movements and DEM changes obtained by multi-temporal analysis of UAV images (provided by SenseFly Swinglet CAM drone). The movement rate obtained by photogrammetry are compared to those obtained by differential GNSS repeated campaigns on almost fifty points distributed on the rock glacier. Results reveals a very good agreements between both rates velocities obtained by the two methods and vertical displacements on fixed points. Strengths, weaknesses and shrewdness of this methods will be discussed. Such a method is very promising mainly for remote regions with difficult access.

A system for ubiquitous fall monitoring at home via a wireless sensor network.

PubMed

Fernandez-Luque, Francisco J; Zapata, Juan; Ruiz, Ramon

2010-01-01

Accidental falls of our elderly, and physical injuries resulting, represent a major health and economic. Falls are the most common causes of serious injuries and a major health threats in the stratum of older population. Early detection of a fall is a key factor when trying to provide adequate care to the elderly person who has suffered an accident at home. In this paper, we present a support system for detecting falls of an elder person by a static wireless nonintrusive sensorial infrastructure based on heterogenous sensor nodes. This previous infrastructure, named AID (Alarm Intelligent Device), is an AAL (Ambient Assisted Living) system that allows to infer a potential fall. We have developed, different to other contributions, a specific low-power multi-hop network consists of nodes (Motes) that wirelessly communicate to each other and are capable of hopping radio messages to a base station where they are passed to a PC (or other possible client). The goal of this project is 1) to provide alerts to caregivers in the event of an accident, acute illness or strange (possibly dangerous) activities, and 2) to enable that authorized and authenticated caregivers by means of a itinerant wearable mote can be inserted into mesh and interact with it. In this paper, we describe an ubiquitous assistential monitoring system at home.

Hazardous Waste Cleanup: Olin Corporation in Niagara Falls, New York

EPA Pesticide Factsheets

The Olin Niagara Falls Plant (the Plant), comprised of two separate lots, is located south of Buffalo Avenue in Niagara Falls, approximately 1,000 feet north of the Upper Niagara River. Historically, Olin produced chlorine and caustic soda from rock salt

Studies on fall armyworm migration and monitoring

USDA-ARS?s Scientific Manuscript database

Spodoptera frugiperda (J.E. Smith; Lepidoptera: Noctuidae) or fall armyworm is an important agricultural pest of a number of crops in thewestern hemisphere. Two morphologically identical host strains of fall armyworm exist, the rice-strain and corn-strain, with the latter inflicting substantial eco...

A posture recognition based fall detection system for monitoring an elderly person in a smart home environment.

PubMed

Yu, Miao; Rhuma, Adel; Naqvi, Syed Mohsen; Wang, Liang; Chambers, Jonathon

2012-11-01

We propose a novel computer vision based fall detection system for monitoring an elderly person in a home care application. Background subtraction is applied to extract the foreground human body and the result is improved by using certain post-processing. Information from ellipse fitting and a projection histogram along the axes of the ellipse are used as the features for distinguishing different postures of the human. These features are then fed into a directed acyclic graph support vector machine (DAGSVM) for posture classification, the result of which is then combined with derived floor information to detect a fall. From a dataset of 15 people, we show that our fall detection system can achieve a high fall detection rate (97.08%) and a very low false detection rate (0.8%) in a simulated home environment.

4D monitoring of actively failing rockslopes

NASA Astrophysics Data System (ADS)

Rosser, Nick; Williams, Jack; Hardy, Richard; Brain, Matthew

2017-04-01

Assessing the conditions which promote rockfall to collapse relies upon detailed monitoring, ideally before, during and immediately after failure. With standard repeat surveys it is common that surveys do not coincide with or capture precursors, or that surveys are widely spaced relative to the timing and duration of driving forces such as storms. As a result gaining insight into the controls on failure and the timescales over which precursors operate remains difficult to establish with certainty, and establishing direct links between environmental conditions and rock-falls, or sequences of events prior to rockfall, remain difficult to define. To address this, we present analysis of a high-frequency 3D laser scan dataset captured using a new permanently installed system developed to constantly monitor actively failing rock slopes. The system is based around a time of flight laser scanner, integrated with and remotely controlled by dedicated controls and analysis software. The system is configured to capture data at 0.1 m spacing across > 22,000 m3 at up to 30 minute intervals. Here we present results captured with this system over a period of 9 months, spanning spring to winter 2015. Our analysis is focussed upon improving the understanding of the nature of small (< 1m^3) rockfalls falling from near vertical rock cliffs. We focus here on the development of a set of algorithms for differencing that trade-off the temporal resolution of frequent surveys (hourly) against high spatial resolution point clouds (< 0.05 m) to enhance the precision of change detection, allowing both deformation and detachments to be monitored through time. From this dataset we derive rockfall volume frequency distributions based upon short-interval surveys, and identify the presence and/or absence of precursors, in what we believe to be the first constant volumetric measurement of rock face erosion. The results hold implications for understanding of rockfall mechanics, but also for how

Litter fall from shrubs in the northern Majove Desert

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strojan, C.L.; Turner,F.B.; Castetter, R.

1979-10-01

Plant litter was collected in traps from 8 to 10 replicates each of Ambrosia dumosa, Ephedra nevadensis, Krameria parvifolia, Larrea tradentata, Lycium andersonii, and Lycium pallidum in Rock Valley, southern Nevada, USA. Collections were made at biweekly to monthly intervals from 1975 to 1977 and handsorted into leaves, stems, flowers, and fruits. Litter fall was generally correlated with annual rainfall, which was low in 1975 (62 mm), high in 1976 (223 mm), and close to the longterm mean in 1977 (141 mm). Leaves were generally the largest litter category, followed by stems, fruits, and flowers. Large sample variations were found,more » particularly for reproductive parts. Aboveground litter fall from the six species, which comprise approx. = 82% of pernnial plant biomass and approx. = 81% of shrub cover in Rock Valley, was about 117 kg/ha in 1975 and 318 kg/ha in 1976. Total aboveground litter fall for Rock Valley (all perennial and annual plants) was estimated to be 194 kg/ha in 1975 and 530 kg/ha in 1976. Distinct litter fall patterns occurred for shrub species and litter categories. Most litter fell during the summer months, with individual species peaks reflecting particular phenologies. Significant amounts of live aboveground biomass were shed as litter. Amounts of litter from the six species ranged from 7 to 83% of their respective live aboveground biomass.« less

Assessment of the potential of the rock gunnel (Pholis gunnellus) along the Atlantic coast of Canada as a species for monitoring the reproductive impacts of contaminant exposures.

PubMed

Vallis, L; MacLatchy, D L; Munkittrick, K R

2007-05-01

Evaluating the impacts of point source discharges on fish species in estuarine environments can be challenging because of a paucity of resident species. We evaluated the biology of rock gunnel (Pholis gunnellus) at three relatively uncontaminated sites in the Bay of Fundy, along the Atlantic coast of Canada. Rock gunnel are seasonally resident (April to November) in tide pools, but little was known about their life history in Atlantic Canada or their potential for use for monitoring environmental quality. Fish were collected between April and November, and ranged from 2.46 g-15.2g in weight and 97 mm-170 mm in length, with a maximum age of 7 years. Both males and females were similar in size, and both reached sexual maturity at a size of 5.5 g. Organ weights and condition indices of fish were stable from spring when they returned from offshore (April to May) until late summer (August to September), but fall fish (October to November) had slightly larger gonads, livers and condition indices. Rock gunnel may be a useful indicator to provide insight into local impacts of point sources over a short time period. However, they do not provide adequate information on reproductive development and performance since they are not exposed to onshore contaminants during the periods of gonadal development that have most commonly found to be sensitive to anthropogenic stressors.

Impedance-Based Pre-Stress Monitoring of Rock Bolts Using a Piezoceramic-Based Smart Washer-A Feasibility Study.

PubMed

Wang, Bo; Huo, Linsheng; Chen, Dongdong; Li, Weijie; Song, Gangbing

2017-01-27

Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a "smart washer" with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a rock bolt specimen. By applying high-frequency sweep excitations (typically >30 kHz) to the smart washer that was installed on the rock bolt specimen, we observed that the variation in impedance signatures indicated the rock bolt pre-stress status. With the degradation of rock bolt pre-stress, the frequency in the dominating peak of the real part of the electrical impedance signature increased. To quantify the effectiveness of the proposed technique, a normalized root mean square deviation (RMSD) index was developed to evaluate the degradation level of the rock bolt pre-stress. The experimental results demonstrated that the normalized RMSD-based looseness index, which was computed from the impedance value detected by the "smart washer", increased with loss of the pre-stress of the rock bolt. Therefore, the proposed method can effectively detect the degradation of rock bolt pre-stress, as demonstrated by experiments.

Impedance-Based Pre-Stress Monitoring of Rock Bolts Using a Piezoceramic-Based Smart Washer—A Feasibility Study

PubMed Central

Wang, Bo; Huo, Linsheng; Chen, Dongdong; Li, Weijie; Song, Gangbing

2017-01-01

Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a “smart washer” with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a rock bolt specimen. By applying high-frequency sweep excitations (typically >30 kHz) to the smart washer that was installed on the rock bolt specimen, we observed that the variation in impedance signatures indicated the rock bolt pre-stress status. With the degradation of rock bolt pre-stress, the frequency in the dominating peak of the real part of the electrical impedance signature increased. To quantify the effectiveness of the proposed technique, a normalized root mean square deviation (RMSD) index was developed to evaluate the degradation level of the rock bolt pre-stress. The experimental results demonstrated that the normalized RMSD-based looseness index, which was computed from the impedance value detected by the “smart washer”, increased with loss of the pre-stress of the rock bolt. Therefore, the proposed method can effectively detect the degradation of rock bolt pre-stress, as demonstrated by experiments. PMID:28134811

Gold Veins near Great Falls, Maryland

USGS Publications Warehouse

Reed, John Calvin; Reed, John C.

1969-01-01

Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian (?) age. The veins cut granitic rocks of Devonian or pre-Devonian age and may be as young as Triassic. Further development of the deposits is unlikely under present economic conditions because of their generally low gold content and because much of the vein system lies on park property, but study of the Great Falls vein system may be useful in the search for similar deposits elsewhere in the Appalachian Piedmont.

Quantifying rock mass strength degradation in coastal rock cliffs

NASA Astrophysics Data System (ADS)

Brain, Matthew; Lim, Michael; Rosser, Nick; Petley, David; Norman, Emma; Barlow, John

2010-05-01

Although rock cliffs are generally perceived to evolve through undercutting and cantilever collapse of material, the recent application of high-resolution three-dimensional monitoring techniques has suggested that the volumetric losses recorded from layers above the intertidal zone produce an equally significant contribution to cliff behaviour. It is therefore important to understand the controls on rockfalls in such layers. Here we investigate the progressive influence of subaerial exposure and weathering on the geotechnical properties of the rocks encountered within the geologically complex coastal cliffs of the northeast coast of England, UK. Through a program of continuous in situ monitoring of local environmental and tidal conditions and laboratory rock strength testing, we aim to better quantify the relationships between environmental processes and the geotechnical response of the cliff materials. We have cut fresh (not previously exposed) samples from the three main rock types (sandstone, mudstone and shale) found within the cliff to uniform size, shape and volume, thus minimizing variability and removing previous surface weathering effects. In order to characterise the intact strength of the rocks, we have undertaken unconfined compressive strength and triaxial strength tests using high pressure (400 kN maximum axial load; 64 MPa maximum cell pressure) triaxial testing apparatus. The results outline the peak strength characteristics of the unweathered materials. We then divided the samples of each lithology into different experimental groups. The first set of samples remained in the laboratory at constant temperature and humidity; this group provides our control. Samples from each of the three rock types were located at heights on the cliff face corresponding with the different lithologies: at the base (mudstone), in the mid cliff (shale) and at the top of the cliff (sandstone). This subjected them to the same conditions experienced by the in situ cliff

Development of a quantitative model for the mechanism of raveling failure in highway rock slopes using LIDAR.

DOT National Transportation Integrated Search

2013-03-01

Rock falls on highways while dangerous are unpredictable. Most rock falls are of the raveling type and not conducive to stability : calculations, and even the failure mechanisms are not well understood. LIDAR (LIght Detection And Ranging) has been sh...

Cloud-Based Smart Health Monitoring System for Automatic Cardiovascular and Fall Risk Assessment in Hypertensive Patients.

PubMed

Melillo, P; Orrico, A; Scala, P; Crispino, F; Pecchia, L

2015-10-01

The aim of this paper is to describe the design and the preliminary validation of a platform developed to collect and automatically analyze biomedical signals for risk assessment of vascular events and falls in hypertensive patients. This m-health platform, based on cloud computing, was designed to be flexible, extensible, and transparent, and to provide proactive remote monitoring via data-mining functionalities. A retrospective study was conducted to train and test the platform. The developed system was able to predict a future vascular event within the next 12 months with an accuracy rate of 84 % and to identify fallers with an accuracy rate of 72 %. In an ongoing prospective trial, almost all the recruited patients accepted favorably the system with a limited rate of inadherences causing data losses (<20 %). The developed platform supported clinical decision by processing tele-monitored data and providing quick and accurate risk assessment of vascular events and falls.

Vulnerabilities to Rock-Slope Failure Impacts from Christchurch, NZ Case History Analysis

NASA Astrophysics Data System (ADS)

Grant, A.; Wartman, J.; Massey, C. I.; Olsen, M. J.; Motley, M. R.; Hanson, D.; Henderson, J.

2015-12-01

Rock-slope failures during the 2010/11 Canterbury (Christchurch), New Zealand Earthquake Sequence resulted in 5 fatalities and caused an estimated US$400 million of damage to buildings and infrastructure. Reducing losses from rock-slope failures requires consideration of both hazard (i.e. likelihood of occurrence) and risk (i.e. likelihood of losses given an occurrence). Risk assessment thus requires information on the vulnerability of structures to rock or boulder impacts. Here we present 32 case histories of structures impacted by boulders triggered during the 2010/11 Canterbury earthquake sequence, in the Port Hills region of Christchurch, New Zealand. The consequences of rock fall impacts on structures, taken as penetration distance into structures, are shown to follow a power-law distribution with impact energy. Detailed mapping of rock fall sources and paths from field mapping, aerial lidar digital elevation model (DEM) data, and high-resolution aerial imagery produced 32 well-constrained runout paths of boulders that impacted structures. Impact velocities used for structural analysis were developed using lumped mass 2-D rock fall runout models using 1-m resolution lidar elevation data. Model inputs were based on calibrated surface parameters from mapped runout paths of 198 additional boulder runouts. Terrestrial lidar scans and structure from motion (SfM) imagery generated 3-D point cloud data used to measure structural damage and impacting boulders. Combining velocity distributions from 2-D analysis and high-precision boulder dimensions, kinetic energy distributions were calculated for all impacts. Calculated impact energy versus penetration distance for all cases suggests a power-law relationship between damage and impact energy. These case histories and resulting fragility curve should serve as a foundation for future risk analysis of rock fall hazards by linking vulnerability data to the predicted energy distributions from the hazard analysis.

The RHYTMME system: an operational real-time warning and mapping system for flash floods, debris flows, landslide and rock falls in Southeastern France.

NASA Astrophysics Data System (ADS)

Fouchier, Catherine; Mériaux, Patrice; Atger, Frédéric; Ecrepont, Stéphane; Liébault, Frédéric; Bertrand, Mélanie; Bel, Coraline; Batista, Dominique; Azemard, Pierre; Saint-Martin, Clotilde; Javelle, Pierre

2016-04-01

Almost all municipalities of Southeastern France are concerned by natural hazards triggered by heavy rainfalls such as floods, debris flows, landslides and rock falls. Although some tools exist to forecast and monitor heavy rains and floods in France, their spatial resolution sometimes does not meet the needs of local risk managers who have to monitor events at a small spatial scale. In order to improve the risk management in the mountainous and Mediterranean areas of Southeastern France, Irstea and Météo-France have led the RHYTMME project. The goal of this project is to improve the ability to forecast and localize high-risk rainfall-induced hazards in the Provence-Alpes-Côte d'Azur administrative area. This goal is currently under achievement thanks to the implementation of a real-time warning and mapping system for rainfall induced natural hazards, fed by radar data and whose outputs are made available via the Internet to operators in charge of risk management (local and regional authorities, emergency and rescue services, road and rail networks managers, ...). This system provides maps which display in real-time: - the radar estimations of rainfall for different rain durations and at the spatial resolution of 1 km² (Westrelin et al., 2013), - the estimation of the scarcity of these rainfall estimations, also at the spatial resolution of 1 km², thanks to a comparison with threshold values provided by a regionalized stochastic hourly point rainfall generator (Arnaud et al., 2007), - an anticipation of the rivers discharges, computed at the outlet of 1700 watersheds of Southeastern France thanks to the AIGA warning system which combines a rainfall runoff model and an estimation of the scarcity of the discharges thanks to a comparison with threshold values (Javelle et al., 2014). Maps of susceptibility to debris flow, landslide and rock falls can also be displayed in the RHYTMME warning system along with the real time maps of rainfall hazard (Batista, 2013a

Niagara Falls Storage Site annual site environmental monitoring report. Calendar year 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1986-04-01

During 1985, an environmental monitoring program was continued at the Niagara Falls Storage Site (NFSS), a United States Department of Energy (DOE) surplus facility located in Niagara County, New York, presently used for the interim storage of low-level radioactive residues and contaminated soils and rubble. The monitoring program is being conducted by Bechtel National, Inc. Monitoring results show that the NFSS is in compliance with DOE concentration guides and radiation protection standards. Derived Concentration Guides (DCGs) represent the concentrations of radionuclides in air or water that would limit the radiation dose to 100 mrem/yr. The applicable limits have been revisedmore » since the 1984 environmental monitoring report was published. The limits applied in 1984 were based on a radiation protection standard of 500 mrem/yr; the limits applied for the 1985 are based on a standard of 100 mrem/yr. To determine whether the site is in compliance with DOE standards, environmental measurements are expressed as percentages of the applicable DCG, while the calculated doses to the public are expressed as percentages of the applicable radiation protection standard. The monitoring program measured radon gas concentrations in air; uranium and radium concentrations in surface water, groundwater, and sediments; and external gamma dose rates. Environmental samples collected were analyzed to determine compliance with applicable standards. Potential radiation doses to the public were also calculated.« less

High Speed Videometric Monitoring of Rock Breakage

NASA Astrophysics Data System (ADS)

Allemand, J.; Shortis, M. R.; Elmouttie, M. K.

2018-05-01

Estimation of rock breakage characteristics plays an important role in optimising various industrial and mining processes used for rock comminution. Although little research has been undertaken into 3D photogrammetric measurement of the progeny kinematics, there is promising potential to improve the efficacy of rock breakage characterisation. In this study, the observation of progeny kinematics was conducted using a high speed, stereo videometric system based on laboratory experiments with a drop weight impact testing system. By manually tracking individual progeny through the captured video sequences, observed progeny coordinates can be used to determine 3D trajectories and velocities, supporting the idea that high speed video can be used for rock breakage characterisation purposes. An analysis of the results showed that the high speed videometric system successfully observed progeny trajectories and showed clear projection of the progeny away from the impact location. Velocities of the progeny could also be determined based on the trajectories and the video frame rate. These results were obtained despite the limitations of the photogrammetric system and experiment processes observed in this study. Accordingly there is sufficient evidence to conclude that high speed videometric systems are capable of observing progeny kinematics from drop weight impact tests. With further optimisation of the systems and processes used, there is potential for improving the efficacy of rock breakage characterisation from measurements with high speed videometric systems.

Type and Location of Wearable Sensors for Monitoring Falls during Static and Dynamic Tasks in Healthy Elderly: A Review

PubMed Central

Sorriso, Antonietta; Liparoti, Marianna; Ferraioli, Giampaolo; Sorrentino, Pierpaolo

2018-01-01

In recent years, the meaning of successful living has moved from extending lifetime to improving the quality of aging, mainly in terms of high cognitive and physical functioning together with avoiding diseases. In healthy elderly, falls represent an alarming accident both in terms of number of events and the consequent decrease in the quality of life. Stability control is a key approach for studying the genesis of falls, for detecting the event and trying to develop methodologies to prevent it. Wearable sensors have proved to be very useful in monitoring and analyzing the stability of subjects. Within this manuscript, a review of the approaches proposed in the literature for fall risk assessment, fall prevention and fall detection in healthy elderly is provided. The review has been carried out by using the most adopted publication databases and by defining a search strategy based on keywords and boolean algebra constructs. The analysis aims at evaluating the state of the art of such kind of monitoring, both in terms of most adopted sensor technologies and of their location on the human body. The review has been extended to both dynamic and static analyses. In order to provide a useful tool for researchers involved in this field, the manuscript also focuses on the tests conducted in the analyzed studies, mainly in terms of characteristics of the population involved and of the tasks used. Finally, the main trends related to sensor typology, sensor location and tasks have been identified. PMID:29783647

Deformation Monitoring of Waste-Rock-Backfilled Mining Gob for Ground Control

PubMed Central

Zhao, Tongbin; Zhang, Yubao; Zhang, Zhenyu; Li, Zhanhai; Ma, Shuqi

2017-01-01

Backfill mining is an effective option to mitigate ground subsidence, especially for mining under surface infrastructure, such as buildings, dams, rivers and railways. To evaluate its performance, continual long-term field monitoring of the deformation of backfilled gob is important to satisfy strict public scrutiny. Based on industrial Ethernet, a real-time monitoring system was established to monitor the deformation of waste-rock-backfilled gob at −700 m depth in the Tangshan coal mine, Hebei Province, China. The designed deformation sensors, based on a resistance transducer mechanism, were placed vertically between the roof and floor. Stress sensors were installed above square steel plates that were anchored to the floor strata. Meanwhile, data cables were protected by steel tubes in case of damage. The developed system continually harvested field data for three months. The results show that industrial Ethernet technology can be reliably used for long-term data transmission in complicated underground mining conditions. The monitoring reveals that the roof subsidence of the backfilled gob area can be categorized into four phases. The bearing load of the backfill developed gradually and simultaneously with the deformation of the roof strata, and started to be almost invariable when the mining face passed 97 m. PMID:28475168

Deformation Monitoring of Waste-Rock-Backfilled Mining Gob for Ground Control.

PubMed

Zhao, Tongbin; Zhang, Yubao; Zhang, Zhenyu; Li, Zhanhai; Ma, Shuqi

2017-05-05

Backfill mining is an effective option to mitigate ground subsidence, especially for mining under surface infrastructure, such as buildings, dams, rivers and railways. To evaluate its performance, continual long-term field monitoring of the deformation of backfilled gob is important to satisfy strict public scrutiny. Based on industrial Ethernet, a real-time monitoring system was established to monitor the deformation of waste-rock-backfilled gob at -700 m depth in the Tangshan coal mine, Hebei Province, China. The designed deformation sensors, based on a resistance transducer mechanism, were placed vertically between the roof and floor. Stress sensors were installed above square steel plates that were anchored to the floor strata. Meanwhile, data cables were protected by steel tubes in case of damage. The developed system continually harvested field data for three months. The results show that industrial Ethernet technology can be reliably used for long-term data transmission in complicated underground mining conditions. The monitoring reveals that the roof subsidence of the backfilled gob area can be categorized into four phases. The bearing load of the backfill developed gradually and simultaneously with the deformation of the roof strata, and started to be almost invariable when the mining face passed 97 m.

Research in rock deformation: Report of the Second Rock Deformation Colloquium, 1989 AGU Spring Meeting

NASA Astrophysics Data System (ADS)

Green, Harry

In response to the considerable interest expressed at the first Rock Deformation Colloquium held at the Fall 1988 AGU meeting in San Francisco, a second dinner meeting was held on Monday evening, May 8, 1989, at the Omni Hotel in Baltimore. The principal business items were a report by Steve Kirby (U.S. Geological Survey, Menlo Park, Calif.) concerning the meeting the previous day of the rock deformation steering committee and an after dinner presentation by Steve Freiman of the National Institute of Standards and Technology in Gaithersburg, Md., entitled “The Environmental Effects on Subcritical Crack Growth.” Kirby reported that a technical committee for rock deformation has been established within the Tectonophysics Section of AGU; the steering committee will attempt to establish constructive working relations with allied societies and disciplines, such as ceramics, metallurgy, materials science, structural geology, and surface science. Brian Evans of the Massachusetts Institute of Technology in Cambridge, Terry Tullis of Brown University in Providence, R.I., and Harry Green of the University of California at Davis agreed to be a subcommittee to propose a name for the technical committee, for discussion at the next steering committee meeting to be held before the 1989 Fall AGU meeting. Green also agreed to investigate the possibility of convening a special session at the Fall Meeting on the nature and mechanism of deep-focus earthquakes. (The session is Deep Slab Deformation and Faulting, T21B and T22A, organized by Harry and Ken Creager of the University of Washington, Seattle; it will be all day on Tuesday, December 5.)

Monitoring rock glacier dynamics and ground temperatures in the semiarid Andes (Chile, 30°S)

NASA Astrophysics Data System (ADS)

Brenning, Alexander; Azócar, Guillermo F.; Bodin, Xavier

2013-04-01

Rock glaciers and mountain permafrost are widespread in the high semiarid Andes of Chile, where they concentrate greater amounts of ice than glaciers. Rock glaciers are of particular interest because in some cases the permafrost they contain might be in a degrading in response to climatic warming. This could result in increased dynamics and even to destabilization, which has been observed on some rock glaciers in the studied area. Displacement rates and active-layer temperatures of two rock glaciers as well as ground surface temperatures of the periglacial environment in the upper Elqui valley have been monitored since summer 2009/10 with funding from the Chilean Dirección General de Aguas. Differential GPS measurements of 115 points on the surface of two rock glaciers since April 2010 showed horizontal displacements of up to 1.3 m/a on the Llano de las Liebres rock glacier and up to 1.2 m/a on the Tapado rock glacier. General velocity patterns are consistent with the morphological evidence of activity (e.g., front slopes, looseness of debris) and for the Tapado complex, a clearly distinct activity from the debris-covered glacier was observed. Temperature measurements in four boreholes indicate active-layer depths of about 2.5 m at the highest locations on the Tapado rock glacier (~4400 m a.s.l.) and about 8 m near the front of the Llano rock glacier (3786 m a.s.l.). Spatial patterns of mean ground surface temperature (MGST) were analyzed with regards to influences of elevation, potential incoming solar radiation, location on ice-debris landforms (rock and debris-covered glaciers), and snow cover duration using linear mixed-effects models. While accounting for the other variables, sites with long-lasting snow patches had ~0.4°C lower MGST, and ice-debris landforms had ~0.4-0.6°C lower MGST than general debris surfaces, highlighting important local modifications to the general topographic variation of ground thermal conditions.

Scattering from Rock and Rock Outcrops

DTIC Science & Technology

2018-01-23

scattering and rough areas as seen on the rock outcrop in Fig. 1, display high variability which could pose difficulty for target detection and...classification systems. The primary long-term goal of this research project is to increase understanding and modeling capabilities for high -frequency acoustic...Arlington, VA 22203-1995 10. SPONSOR/MONITOR’S ACRONYM(S) BD025 11. SPONSORING/MONITORING AGENCY REPORT NUMBER 12. DISTRIBUTION AVAILABILITY

Using monitoring and modeling to define the hazard posed by the reactivated Ferguson rock slide, Merced Canyon, California

USGS Publications Warehouse

De Graff, Jerome V.; Gallegos, Alan J.; Reid, Mark E.; Lahusen, Richard G.; Denlinger, Roger P.

2015-01-01

Rapid onset natural disasters such as large landslides create a need for scientific information about the event, which is vital to ensuring public safety, restoring infrastructure, preventing additional damage, and resuming normal economic activity. At the same time, there is limited data available upon which to base reliable scientific responses. Monitoring movement and modeling runout are mechanisms for gaining vital data and reducing the uncertainty created about a rapid onset natural disaster. We examine the effectiveness of this approach during the 2006 Ferguson rock slide disaster, which severed California Highway 140. Even after construction of a bypass restoring normal access to the community of El Portal, CA and a major entrance to Yosemite National Park, significant scientific questions remained. The most important for the affected public and emergency service agencies was the likelihood that access would again be severed during the impending rainy season and the possibility of a landslide dam blocking flow in the Merced River. Real-time monitoring of the Ferguson rock slide yielded clear information on the continuing movement of the rock slide and its implications for emergency response actions. Similarly, simulation of runout deposits using a physically based model together with volumes and slope steepness information demonstrated the conditions necessary for a landslide dam-forming event and the possible consequences of such an event given the dimensions of potential rock slide deposits.

Slope monitoring by using 2-D resistivity method at Sungai Batu, Pulau Pinang, Malaysia

NASA Astrophysics Data System (ADS)

Azman, Muhamad Iqbal Mubarak Faharul; Yusof, Azim Hilmy Mohd; Ismail, Nur Azwin; Ismail, Noer El Hidayah

2017-07-01

Slope is a dynamic system of geo-environmental phenomena that related to the movement of the soil and rock masses. In Pulau Pinang, the occurrence of slope related phenomena such as landslide and rock fall has become a huge issue especially during rainy season as the government would have to invest more for the people safety. 2-D resistivity method is one of the geophysical methods that can be applied to overcome this issue thus prepare countermeasure actions. Monitoring is one of the common acquisition technique that has been used in solving such issue. This technique was applied to identify and monitor changes at the suspected area and thus, countermeasure steps can be taken accordingly and not blindfolded. Starting from August until November 2016, a 200 m survey line of 2-D resistivity survey had been conducted monthly at Sungai Batu, Pulau Pinang slope for monitoring purpose. Three resistivity ranges were able to detect within the subsurface. Resistivity value of 250 - 400 Ωm indicated the low resistivity value and interpreted as the weak zone located at distance of 90 - 120 m with depth of 10 m. Intermediate resistivity value was interpreted as weathered granite zone with resistivity value of 400 - 1500 Ωm was found at almost along survey line. High resistivity value was > 5000 Ωm and interpreted as granitic bedrock located at depth of > 20 m. Aside from weathered granite zone and weak zone, a fracture was found develop over time at distance of 130 - 140 m. The features found have the potential to be the cause for slope failure phenomena to occur. As a conclusion, monitoring slope using 2-D resistivity method is a success and indeed helpful in overcome landslide and rock fall issue as a pre-countermeasure action.

Monitoring Fluid Flow in Fractured Carbonate Rocks Using Seismic Measurements

NASA Astrophysics Data System (ADS)

Li, W.; Pyrak-Nolte, L. J.

2008-12-01

The physical properties of carbonate rock are strongly influenced by the rock fabric which depends on the depositional environment, diagenetic and tectonic processes. The most common form of heterogeneity is layering caused by a variation in porosity among layers and within layers. The variation in porosity among layers leads to anisotropic behavior in the hydraulic, mechanical and seismic properties of carbonate rocks. We present the results of a laboratory study to examine the effect of fabric-controlled layering on fluid flow and seismic wave propagation through intact and fractured carbonate rock. Experiments were performed on cubic samples of Austin Chalk Cordova Cream. Samples AC1, AC5 and AC6 are cubic samples that measure 100 mm on edge. The samples were sealed and contained three inlet and three outlet ports for fluid invasion experiments. Two orthogonal seismic arrays were used to record both compressional and shear wave transmission through intact and fractured samples. The arrays used piezoelectric contact transducers with a central frequency 1.0 MHz. Between the two arrays, sixteen sources and sixteen receivers were used. Seismic measurements were made on the samples as a function of stress and during fluid saturation. The location of the invading fluid front as a function of time was monitored by using the peak-to-peak amplitude of the transmitted signals. The front was assumed to be between a source-receiver pair when the signal amplitude decreased by 50% over the initial value. The hydraulic gradient was parallel and perpendicular to the layers for AC5 and AC6, respectively. Sample AC1 was fractured and flow ports were established on the edges of the fracture plane. The weakly directed fabric controlled the rate at which fluid flowed through the samples. From the seismic data on AC6, the fluid first spread vertically along a layer before flowing across the layers. For AC6, it took the fluid two and half hours to flow between the inlet and the outlet

2. View of Potomac River at Great Falls looking upstream ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. View of Potomac River at Great Falls looking upstream from Observation Tower. The majestic character of this wild and untrammeled spot is vividly shown. Scanty flow is evidenced by light colored normal water line markings on rock formation. Washington Agueduct Dam is shown in upper portion. Maryland on right and Virginia on left. Natives quoted as saying the water was as low or lower than during the drought conditions of 1930. Mr. Horyduzak, Photographer, 1943. - Potowmack Company: Great Falls Canal & Locks, Great Falls, Fairfax County, VA

Rock Slope Monitoring from 4D Time-Lapse Structure from Motion Analysis

NASA Astrophysics Data System (ADS)

Kromer, Ryan; Abellan, Antonio; Chyz, Alex; Hutchinson, Jean

2017-04-01

Structure from Motion (SfM) photogrammetry has become an important tool for studying earth surface processes because of its flexibility, ease of use, low cost and its capability of producing high quality 3-D surface models. A major benefit of SfM is that model accuracy is fit for purpose and surveys can be designed to meet a large range of spatial and temporal scales. In the Earth sciences, research in time-lapse SfM photogrammetry or videogrammetry is an area that is difficult to undertake due to complexities in acquiring, processing and managing large 4D datasets and represents an area with significant advancement potential (Eltner et al. 2016). In this study, we investigate the potential of 4D time-lapse SfM to monitor unstable rock slopes. We tested an array of statically mounted cameras collecting time-lapse photos of a limestone rock slope located along a highway in Canada. Our setup consisted of 8 DSLR cameras with 50 mm prime lenses spaced 2-3 m apart at a distance of 10 m from the slope. The portion of the rock slope monitored was 20 m wide and 6 m high. We collected data in four phases, each having 50 photographs taken simultaneously by each camera. The first phase of photographs was taken of the stable slope. In each successive phase, we gradually moved small, discrete blocks within the rock slope by 5-15 mm, simulating pre-failure deformation of rockfall. During the last phase we also removed discrete rock blocks, simulating rockfall. We used Agisoft Photoscan's 4D processing functionality and timeline tools to create 3D point clouds from the time-lapse photographs. These tools have the benefit of attaining better accuracy photo alignments as a greater number of photos are used. For change detection, we used the 4D filtering and calibration technique proposed by Kromer et al. (2015), which takes advantage of high degrees of spatial and temporal point redundancy to decrease measurement uncertainty. Preliminary results show that it is possible to attain

Brittleness Effect on Rock Fatigue Damage Evolution

NASA Astrophysics Data System (ADS)

Nejati, Hamid Reza; Ghazvinian, Abdolhadi

2014-09-01

The damage evolution mechanism of rocks is one of the most important aspects in studying of rock fatigue behavior. Fatigue damage evolution of three rock types (onyx marble, sandstone and soft limestone) with different brittleness were considered in the present study. Intensive experimental tests were conducted on the chosen rock samples and acoustic emission (AE) sensors were used in some of them to monitor the fracturing process. Experimental tests indicated that brittleness strongly influences damage evolution of rocks in the course of static and dynamic loading. AE monitoring revealed that micro-crack density induced by the applied loads during different stages of the failure processes increases as rock brittleness increases. Also, results of fatigue tests on the three rock types indicated that the rock with the most induced micro-cracks during loading cycles has the least fatigue life. Furthermore, the condition of failure surfaces of the studied rocks samples, subjected to dynamic and static loading, were evaluated and it was concluded that the roughness of failure surfaces is influenced by loading types and rock brittleness. Dynamic failure surfaces were rougher than static ones and low brittle rock demonstrate a smoother failure surface compared to high brittle rock.

Bioremediation in fractured rock: 2. Mobilization of chloroethene compounds from the rock matrix

USGS Publications Warehouse

Shapiro, Allen M.; Tiedeman, Claire; Imbrigiotta, Thomas; Goode, Daniel J.; Hsieh, Paul A.; Lacombe, Pierre; DeFlaun, Mary F.; Drew, Scott R.; Curtis, Gary P.

2018-01-01

A mass balance is formulated to evaluate the mobilization of chlorinated ethene compounds (CE) from the rock matrix of a fractured mudstone aquifer under pre- and postbioremediation conditions. The analysis relies on a sparse number of monitoring locations and is constrained by a detailed description of the groundwater flow regime. Groundwater flow modeling developed under the site characterization identified groundwater fluxes to formulate the CE mass balance in the rock volume exposed to the injected remediation amendments. Differences in the CE fluxes into and out of the rock volume identify the total CE mobilized from diffusion, desorption, and nonaqueous phase liquid dissolution under pre- and postinjection conditions. The initial CE mass in the rock matrix prior to remediation is estimated using analyses of CE in rock core. The CE mass mobilized per year under preinjection conditions is small relative to the total CE mass in the rock, indicating that current pump-and-treat and natural attenuation conditions are likely to require hundreds of years to achieve groundwater concentrations that meet regulatory guidelines. The postinjection CE mobilization rate increased by approximately an order of magnitude over the 5 years of monitoring after the amendment injection. This rate is likely to decrease and additional remediation applications over several decades would still be needed to reduce CE mass in the rock matrix to levels where groundwater concentrations in fractures achieve regulatory standards.

Potential weathering by freeze-thaw action in alpine rocks in the European Alps during a nine year monitoring period

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas

2017-11-01

A quantification of rock weathering by freeze-thaw processes in alpine rocks requires at least rock temperature data in high temporal resolution, in high quality, and over a sufficient period of time. In this study up to nine years of rock temperature data (2006-2015) from eleven rock monitoring sites in two of the highest mountain ranges of Austria were analyzed. Data were recorded at a half-hourly or hourly logging interval and at rock depths of 3, 10, and 30-40 cm. These data have been used to quantify mean conditions, ranges, and relationships of the potential near-surface weathering by freeze-thaw action considering volumetric-expansion of ice and ice segregation. For the former, freeze-thaw cycles and effective freeze-thaw cycles for frost shattering have been considered. For the latter, the intensity and duration of freezing events as well as time within the 'frost cracking window' have been analyzed. Results show that the eleven sites are in rather extreme topoclimatic positions and hence represent some of the highest and coolest parts of Austria and therefore the Eastern Alps. Only four sites are presumably affected by permafrost. Most sites are influenced by a long-lasting seasonal snow cover. Freeze-thaw cycles and effective freeze-thaw cycles for frost shattering are mainly affecting the near-surface and are unimportant at few tens of centimeters below the rock surface. The lowest temperatures during freezing events and the shortest freezing events have been quantified at all eleven monitoring sites very close to the surface. The time within the frost cracking window decreases in most cases from the rock surface inwards apart from very cold years/sites with very low temperatures close to the surface. As shown by this study and predicted climate change scenarios, assumed warmer rock temperature conditions in the future at alpine rock walls in Austria will lead to less severe freezing events and to shorter time periods within the frost-cracking window

Quantitative Seismic Interpretation: Applying Rock Physics Tools to Reduce Interpretation Risk

NASA Astrophysics Data System (ADS)

Sondergeld, Carl H.

This book is divided into seven chapters that cover rock physics, statistical rock physics, seismic inversion techniques, case studies, and work flows. On balance, the emphasis is on rock physics. Included are 56 color figures that greatly help in the interpretation of more complicated plots and displays.The domain of rock physics falls between petrophysics and seismics. It is the basis for interpreting seismic observations and therefore is pivotal to the understanding of this book. The first two chapters are dedicated to this topic (109 pages).

A Multicomponent Fall Prevention Strategy Reduces Falls at an Academic Medical Center.

PubMed

France, Dan; Slayton, Jenny; Moore, Sonya; Domenico, Henry; Matthews, Julia; Steaban, Robin L; Choma, Neesha

2017-09-01

While the reduction in fall rates has not kept pace with the reduction of other hospital-acquired conditions, patient safety research and quality improvement (QI) initiatives at the system and hospital levels have achieved positive results and provide insights into potentially effective risk reduction strategies. An academic medical center developed a QI-based multicomponent strategy for fall prevention and pilot tested it for six months in three high-risk units-the Neuroscience Acute Care Unit, the Myelosuppression/Stem Cell Transplant Unit, and the Acute Care for the Elderly Unit-before implementing and evaluating the strategy hospitalwide. The multicomponent fall strategy was evaluated using a pre-post study design. The main outcome measures were falls and falls with harm measured in events per 1,000 patient-days. Fall rates were monitored and compared for three classes of falls: (1) accidental, (2) anticipated physiologic, and (3) unanticipated physiologic. Statistical process control charts showed that the pilot units had achieved significant reductions in falls with harm during the last five months of data collection. Wald test and segmented regression analyses revealed significant improvements in pooled postintervention fall rates, stratified by fall type. The hospitalwide implementation of the program resulted in a 47% overall reduction in falls in the postintervention period. A fall prevention strategy that targeted the spectrum of risk factors produced measurable improvement in fall rates and rates of patient harm. Hospitals must continue developing, rigorously testing, and sharing their results and experiences in implementing and sustaining multicomponent fall prevention strategies. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Bioremediation in Fractured Rock: 2. Mobilization of Chloroethene Compounds from the Rock Matrix.

PubMed

Shapiro, Allen M; Tiedeman, Claire R; Imbrigiotta, Thomas E; Goode, Daniel J; Hsieh, Paul A; Lacombe, Pierre J; DeFlaun, Mary F; Drew, Scott R; Curtis, Gary P

2018-03-01

A mass balance is formulated to evaluate the mobilization of chlorinated ethene compounds (CE) from the rock matrix of a fractured mudstone aquifer under pre- and postbioremediation conditions. The analysis relies on a sparse number of monitoring locations and is constrained by a detailed description of the groundwater flow regime. Groundwater flow modeling developed under the site characterization identified groundwater fluxes to formulate the CE mass balance in the rock volume exposed to the injected remediation amendments. Differences in the CE fluxes into and out of the rock volume identify the total CE mobilized from diffusion, desorption, and nonaqueous phase liquid dissolution under pre- and postinjection conditions. The initial CE mass in the rock matrix prior to remediation is estimated using analyses of CE in rock core. The CE mass mobilized per year under preinjection conditions is small relative to the total CE mass in the rock, indicating that current pump-and-treat and natural attenuation conditions are likely to require hundreds of years to achieve groundwater concentrations that meet regulatory guidelines. The postinjection CE mobilization rate increased by approximately an order of magnitude over the 5 years of monitoring after the amendment injection. This rate is likely to decrease and additional remediation applications over several decades would still be needed to reduce CE mass in the rock matrix to levels where groundwater concentrations in fractures achieve regulatory standards. © 2017, National Ground Water Association.

Improved characterization, monitoring and instability assessment of high rock faces by integrating TLS and GB-InSAR

NASA Astrophysics Data System (ADS)

Bianchetti, Matteo; Agliardi, Federico; Villa, Alberto; Battista Crosta, Giovanni; Rivolta, Carlo

2015-04-01

Rockfall risk analysis require quantifying rockfall onset susceptibility and magnitude scenarios at source areas, and the expected rockfall trajectories and related dynamic quantities. Analysis efforts usually focus on the rockfall runout component, whereas rock mass characterization and block size distribution quantification, monitoring and analysis of unstable rock volumes are usually performed using simplified approaches, due to technological and site-specific issues. Nevertheless, proper quantification of rock slope stability and rockfall magnitude scenarios is key when dealing with high rock walls, where widespread rockfall sources and high variability of release mechanisms and block volumes can result in excessive modelling uncertainties and poorly constrained mitigation measures. We explored the potential of integrating field, remote sensing, structural analysis and stability modelling techniques to improve hazard assessment at the Gallivaggio sanctuary site, a XVI century heritage located along the State Road 36 in the Spluga Valley (Italian Central Alps). The site is impended by a subvertical cliff up to 600 m high, made of granitic orthogneiss of the Truzzo granitic complex (Tambo Nappe, upper Pennidic domain). The rock mass is cut by NNW and NW-trending slope-scale structural lineaments and by 5-6 fracture sets with variable spatial distribution, spacing and persistence, which bound blocks up to tens of cubic meters and control the 3D slope morphology. The area is characterised by widespread rock slope instability from rockfalls to massive failures. Although a 180 m long embankment was built to protect the site from rockfalls, concerns remain about potential large unstable rock volumes or flyrocks projected by the widely observed impact fragmentation of stiff rock blocks. Thus, the authority in charge started a series of periodical GB-InSAR monitoring surveys using LiSALabTM technology (12 surveys in 2011-2014), which outlined the occurrence of unstable

Evaluation of Accelerometer-Based Fall Detection Algorithms on Real-World Falls

PubMed Central

Bagalà, Fabio; Becker, Clemens; Cappello, Angelo; Chiari, Lorenzo; Aminian, Kamiar; Hausdorff, Jeffrey M.; Zijlstra, Wiebren; Klenk, Jochen

2012-01-01

Despite extensive preventive efforts, falls continue to be a major source of morbidity and mortality among elderly. Real-time detection of falls and their urgent communication to a telecare center may enable rapid medical assistance, thus increasing the sense of security of the elderly and reducing some of the negative consequences of falls. Many different approaches have been explored to automatically detect a fall using inertial sensors. Although previously published algorithms report high sensitivity (SE) and high specificity (SP), they have usually been tested on simulated falls performed by healthy volunteers. We recently collected acceleration data during a number of real-world falls among a patient population with a high-fall-risk as part of the SensAction-AAL European project. The aim of the present study is to benchmark the performance of thirteen published fall-detection algorithms when they are applied to the database of 29 real-world falls. To the best of our knowledge, this is the first systematic comparison of fall detection algorithms tested on real-world falls. We found that the SP average of the thirteen algorithms, was (mean±std) 83.0%±30.3% (maximum value = 98%). The SE was considerably lower (SE = 57.0%±27.3%, maximum value = 82.8%), much lower than the values obtained on simulated falls. The number of false alarms generated by the algorithms during 1-day monitoring of three representative fallers ranged from 3 to 85. The factors that affect the performance of the published algorithms, when they are applied to the real-world falls, are also discussed. These findings indicate the importance of testing fall-detection algorithms in real-life conditions in order to produce more effective automated alarm systems with higher acceptance. Further, the present results support the idea that a large, shared real-world fall database could, potentially, provide an enhanced understanding of the fall process and the information needed to design

New horizons in fall prevention.

PubMed

Lord, Stephen R; Close, Jacqueline C T

2018-04-25

Falls pose a major threat to the well-being and quality of life of older people. Falls can result in fractures and other injuries, disability and fear and can trigger a decline in physical function and loss of autonomy. This article synthesises recent published findings on fall risk and mobility assessments and fall prevention interventions and considers how this field of research may evolve in the future. Fall risk topics include the utility of remote monitoring using wearable sensors and recent work investigating brain activation and gait adaptability. New approaches for exercise for fall prevention including dual-task training, cognitive-motor training with exergames and reactive step training are discussed. Additional fall prevention strategies considered include the prevention of falls in older people with dementia and Parkinson's disease, drugs for fall prevention and safe flooring for preventing fall-related injuries. The review discusses how these new initiatives and technologies have potential for effective fall prevention and improved quality of life. It concludes by emphasising the need for a continued focus on translation of evidence into practice including robust effectiveness evaluations of so that resources can be appropriately targeted into the future.

Use of Aerial Photography to Monitor Fall Chinook Salmon Spawning in the Columbia River

DOE Office of Scientific and Technical Information (OSTI.GOV)

Visser, Richard H.; Dauble, Dennis D.; Geist, David R.

2002-11-01

This paper compares two methods for enumerating salmon redds and their application to monitoring spawning activity. Aerial photographs of fall chinook salmon spawning areas in the Hanford Reach of the Columbia River were digitized and mapped using Geographic Information Systems (GIS) techniques in 1994 and 1995 as part of an annual assessment of the population. The number of visible redds from these photographs were compared to counts obtained from visual surveys with fixed wing aircraft. The proportion of the total redds within each of five general survey areas was similar for the two monitoring techniques. However, the total number ofmore » redds based on aerial photographs was 2.2 and 3.0 times higher than those observed during visual surveys for 1994 and 1995, respectively. The divergence in redd counts was most evident near peak spawning activity when the number of redds within individual spawning clusters exceeded 500. Aerial photography improved our ability to monitor numbers of visible salmon redds and to quantify habitat use.« less

Farming with rocks and minerals: challenges and opportunities.

PubMed

Van Straaten, Peter

2006-12-01

In many parts of the world food security is at risk. One of the biophysical root causes of falling per-capita food production is the declining quality and quantity of soils. To reverse this trend and increase soil fertility soil and plant nutrients have to be replenished. This review provides a literature survey of experiences of using multi-nutrient rock fertilizers for soil fertility enhancement from temperate and tropical environments. Advantages and limitations of the application of rock fertilizers are discussed. Examples are provided from two successful nutrient replenishment projects in Africa where locally available rock fertilizers are used on highly leached acid soils. The potential of combining organic materials alongside rock fertilizers in soil fertility replenishment strategies is stressed.

New methods for fall risk prediction.

PubMed

Ejupi, Andreas; Lord, Stephen R; Delbaere, Kim

2014-09-01

Accidental falls are the leading cause of injury-related death and hospitalization in old age, with over one-third of the older adults experiencing at least one fall or more each year. Because of limited healthcare resources, regular objective fall risk assessments are not possible in the community on a large scale. New methods for fall prediction are necessary to identify and monitor those older people at high risk of falling who would benefit from participating in falls prevention programmes. Technological advances have enabled less expensive ways to quantify physical fall risk in clinical practice and in the homes of older people. Recently, several studies have demonstrated that sensor-based fall risk assessments of postural sway, functional mobility, stepping and walking can discriminate between fallers and nonfallers. Recent research has used low-cost, portable and objective measuring instruments to assess fall risk in older people. Future use of these technologies holds promise for assessing fall risk accurately in an unobtrusive manner in clinical and daily life settings.

Geo-structural modelling for potential large rock slide in Machu Picchu

NASA Astrophysics Data System (ADS)

Spizzichino, D.; Delmonaco, G.; Margottini, C.; Mazzoli, S.

2009-04-01

The monumental complex of the Historical Sanctuary of Machu Picchu, declared as World Heritage Site by UNESCO in 1983, is located in the Andean chain at approx. 80 km from Cuzco (Peru) and at an elevation of 2430 m a.s.l. along the Urubamba River Valley. From a geological point of view, the Machu Picchu granitoid pluton, forming part of the larger "Quillabamba granite", is one of a series of plutons intruded along the axial zone of the high Eastern Cordillera Permo-Liassic rift system including a variety of rock types, dominantly granites and granodiorites. The most evident structures at the outcrop scale consist of planar joint sets that may be variably reactivated and exhibiting 4 main orientations. At present, the site is affected by geological risk due to frequent landslides that threaten security and tourist exploitation. In the last years, the international landslide scientific community has promoted a multi-discipline joint programme mainly finalised to slope deformation monitoring and analysis after the warning, launched in 2001, of a potential collapse of the citadel, caused by a huge rock slide. The contribute of the Italian research team was devoted to implement a landslide risk analysis and an innovative remote sensing techniques. The main scope of this work is to present the implementation of a geo-structural modelling aimed at defining present and potential slope stability conditions of the Machu Picchu Citadel. Data have been collected by geological, structural and geomechanical field surveys and laboratory tests in order to reconstruct the geomorphological evolution of the area. Landslide types and evolution are strictly controlled by regional tectonic uplift and structural setting. Several slope instability phenomena have been identified and classified according to mechanism, material involved and state of activity. Rock falls, debris flows, rock slides and debris slides are the main surveyed landslide types. Rock slides and rock falls may produce

Smart rocks and wireless communication system for real-time monitoring and mitigation of bridge scour : a proof-of-concept study.

DOT National Transportation Integrated Search

2013-12-01

This study aims to integrate commercial measurement and communication components into a scour : monitoring system with magnets or electronics embedded in smart rocks, and evaluate and improve its : performance in laboratory and field conditions for t...

69. September 1913 "No. 110. Placing no. 2 rock on ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

69. September 1913 "No. 110. Placing no. 2 rock on top of foundation course which has been previously rolled. Experimental road section." - Crater Lake National Park Roads, Klamath Falls, Klamath County, OR

A novel wearable smart button system for fall detection

NASA Astrophysics Data System (ADS)

Zhuang, Wei; Sun, Xiang; Zhi, Yueyan; Han, Yue; Mao, Hande

2017-05-01

Fall has been the second most cause of accidental injury to death in the world. It has been a serious threat to the physical and mental health of the elders. Therefore, developing wearable node system with fall detecting ability has become increasingly pressing at present. A novel smart button for long-term fall detection is proposed in this paper, which is able to accurately monitor the falling behavior, and sending warning message online as well. The smart button is based on the tri-axis acceleration sensor which is used to collect the body motion signals. By using the statistical metrics of acceleration characteristics, a new SVM classification algorithm with high positive accuracy and stability is proposed so as to classify the falls and activities of daily living, and the results can be real-time displayed on Android based mobile phone. The experiments show that our wearable node system can continuously monitor the falling behavior with positive rate 94.8%.

The fracture criticality of crustal rocks

NASA Astrophysics Data System (ADS)

Crampin, Stuart

1994-08-01

The shear-wave splitting observed along almost all shear-wave ray paths in the Earth's crust is interpreted as the effects of stress-aligned fluid-filled cracks, microcracks, and preferentially oriented pore space. Once away from the free surface, where open joints and fractures may lead to strong anisotropy of 10 per cent or greater, intact ostensibly unfractured crustal rock exhibits a limited range of shear-wave splitting from about 1.5 to 4.5 per cent differential shear-wave velocity anisotropy. Interpreting this velocity anisotropy as normalized crack densities, a factor of less than two in crack radius covers the range from the minimum 1.5 per cent anisotropy observed in intact rock to the 10 per cent observed in heavily cracked almost disaggregated near-surface rocks. This narrow range of crack dimensions and the pronounced effect on rock cohesion suggests that there is a state of fracture criticality at some level of anisotropy between 4.5 and 10 per cent marking the boundary between essentially intact, and heavily fractured rock. When the level of fracture criticality is exceeded, cracking is so severe that there is a breakdown in shear strength, the likelihood of progressive fracturing and the dispersal of pore fluids through enhanced permeability. The range of normalized crack dimensions below fracture criticality is so small in intact rock, that any modification to the crack geometry by even minor changes of conditions or minor deformation (particularly in the presence of high pore-fluid pressures) may change rock from being essentially intact (below fracture criticality) to heavily fractured (above fracture criticality). This recognition of the essential compliance of most crustal rocks, and its effect on shear-wave splitting, has implications for monitoring changes in any conditions affecting the rock mass. These include monitoring changes in reservoir evolution during hydrocarbon production and enhanced oil recovery, and in monitoring changes before

Groundwater monitoring of an open-pit limestone quarry: groundwater characteristics, evolution and their connections to rock slopes.

PubMed

Eang, Khy Eam; Igarashi, Toshifumi; Fujinaga, Ryota; Kondo, Megumi; Tabelin, Carlito Baltazar

2018-03-06

Groundwater flow and its geochemical evolution in mines are important not only in the study of contaminant migration but also in the effective planning of excavation. The effects of groundwater on the stability of rock slopes and other mine constructions especially in limestone quarries are crucial because calcite, the major mineral component of limestone, is moderately soluble in water. In this study, evolution of groundwater in a limestone quarry located in Chichibu city was monitored to understand the geochemical processes occurring within the rock strata of the quarry and changes in the chemistry of groundwater, which suggests zones of deformations that may affect the stability of rock slopes. There are three distinct geological formations in the quarry: limestone layer, interbedded layer of limestone and slaty greenstone, and slaty greenstone layer as basement rock. Although the hydrochemical facies of all groundwater samples were Ca-HCO 3 type water, changes in the geochemical properties of groundwater from the three geological formations were observed. In particular, significant changes in the chemical properties of several groundwater samples along the interbedded layer were observed, which could be attributed to the mixing of groundwater from the limestone and slaty greenstone layers. On the rainy day, the concentrations of Ca 2+ and HCO 3 - in the groundwater fluctuated notably, and the groundwater flowing along the interbedded layer was dominated by groundwater from the limestone layer. These suggest that groundwater along the interbedded layer may affect the stability of rock slopes.

Developing a pheromone monitoring network in Africa for fall armyworm

USDA-ARS?s Scientific Manuscript database

The fall armyworm, Spodoptera frugiperda, was discovered infesting maize in São Tomé and Principe and Nigeria in early 2016. The pest species has since been discovered in almost every country in sub-Saharan Africa. Fall armyworm is migratory in North America, moving in the spring from southern ove...

Topography changes monitoring of small islands using camera drone

NASA Astrophysics Data System (ADS)

Bang, E.

2017-12-01

Drone aerial photogrammetry was conducted for monitoring topography changes of small islands in the east sea of Korea. Severe weather and sea wave is eroding the islands and sometimes cause landslide and falling rock. Due to rugged cliffs in all direction and bad accessibility, ground based survey methods are less efficient in monitoring topography changes of the whole area. Camera drones can provide digital images and movie in every corner of the islands, and drone aerial photogrammetry is powerful to get precise digital surface model (DSM) for a limited area. We have got a set of digital images to construct a textured 3D model of the project area every year since 2014. Flight height is in less than 100m from the top of those islands to get enough ground sampling distance (GSD). Most images were vertically captured with automatic flights, but we also flied drones around the islands with about 30°-45° camera angle for constructing 3D model better. Every digital image has geo-reference, but we set several ground control points (GCPs) on the islands and their coordinates were measured with RTK surveying methods to increase the absolute accuracy of the project. We constructed 3D textured model using photogrammetry tool, which generates 3D spatial information from digital images. From the polygonal model, we could get DSM with contour lines. Thematic maps such as hill shade relief map, aspect map and slope map were also processed. Those maps make us understand topography condition of the project area better. The purpose of this project is monitoring topography change of these small islands. Elevation difference map between DSMs of each year is constructed. There are two regions showing big negative difference value. By comparing constructed textured models and captured digital images around these regions, it is checked that a region have experienced real topography change. It is due to huge rock fall near the center of the east island. The size of fallen rock can be

k-t Acceleration in pure phase encode MRI to monitor dynamic flooding processes in rock core plugs

NASA Astrophysics Data System (ADS)

Xiao, Dan; Balcom, Bruce J.

2014-06-01

Monitoring the pore system in sedimentary rocks with MRI when fluids are introduced is very important in the study of petroleum reservoirs and enhanced oil recovery. However, the lengthy acquisition time of each image, with pure phase encode MRI, limits the temporal resolution. Spatiotemporal correlations can be exploited to undersample the k-t space data. The stacked frames/profiles can be well approximated by an image matrix with rank deficiency, which can be recovered by nonlinear nuclear norm minimization. Sparsity of the x-t image can also be exploited for nonlinear reconstruction. In this work the results of a low rank matrix completion technique were compared with k-t sparse compressed sensing. These methods are demonstrated with one dimensional SPRITE imaging of a Bentheimer rock core plug and SESPI imaging of a Berea rock core plug, but can be easily extended to higher dimensionality and/or other pure phase encode measurements. These ideas will enable higher dimensionality pure phase encode MRI studies of dynamic flooding processes in low magnetic field systems.

Activity Monitoring and Heart Rate Variability as Indicators of Fall Risk: Proof-of-Concept for Application of Wearable Sensors in the Acute Care Setting.

PubMed

Razjouyan, Javad; Grewal, Gurtej Singh; Rishel, Cindy; Parthasarathy, Sairam; Mohler, Jane; Najafi, Bijan

2017-07-01

Growing concern for falls in acute care settings could be addressed with objective evaluation of fall risk. The current proof-of-concept study evaluated the feasibility of using a chest-worn sensor during hospitalization to determine fall risk. Physical activity and heart rate variability (HRV) of 31 volunteers admitted to a 29-bed adult inpatient unit were recorded using a single chest-worn sensor. Sensor data during the first 24-hour recording were analyzed. Participants were stratified using the Hendrich II fall risk assessment into high and low fall risk groups. Univariate analysis revealed age, daytime activity, nighttime side lying posture, and HRV were significantly different between groups. Results suggest feasibility of wearable technology to consciously monitor physical activity, sleep postures, and HRV as potential markers of fall risk in the acute care setting. Further study is warranted to confirm the results and examine the efficacy of the proposed wearable technology to manage falls in hospitals. [Journal of Gerontological Nursing, 43(7), 53-62.]. Copyright 2017, SLACK Incorporated.

Staircase Falls Rockfall on December 26, 2003, and Geologic Hazards at Curry Village, Yosemite National Park, California

USGS Publications Warehouse

Wieczorek, Gerald F.; Snyder, James B.; Borchers, James W.; Reichenbach, Paola

2007-01-01

Since 1857, several hundred rockfalls, rockslides, and debris flows have been observed in Yosemite National Park. At 12:45 a.m. on December 26, 2003, a severe winter storm triggered a rockfall west of Glacier Point in Yosemite Valley. Rock debris moved quickly eastward down Staircase Falls toward Curry Village. As the rapidly moving rock mass reached talus at the bottom of Staircase Falls, smaller pieces of flying rock penetrated occupied cabins. Physical characterization of the rockfall site included rockfall volume, joint patterns affecting initial release of rock and the travel path of rockfall, factors affecting weathering and weakening of bedrock, and hydrology affecting slope stability within joints. Although time return intervals are not predictable, a three-dimensional rockfall model was used to assess future rockfall potential and risk. Predictive rockfall and debris-flow methods suggest that landslide hazards beneath these steep cliffs extend farther than impact ranges defined from surface talus in Yosemite Valley, leaving some park facilities vulnerable.

Mobility Effect on Poroelastic Seismic Signatures in Partially Saturated Rocks With Applications in Time-Lapse Monitoring of a Heavy Oil Reservoir

NASA Astrophysics Data System (ADS)

Zhao, Luanxiao; Yuan, Hemin; Yang, Jingkang; Han, De-hua; Geng, Jianhua; Zhou, Rui; Li, Hui; Yao, Qiuliang

2017-11-01

Conventional seismic analysis in partially saturated rocks normally lays emphasis on estimating pore fluid content and saturation, typically ignoring the effect of mobility, which decides the ability of fluids moving in the porous rocks. Deformation resulting from a seismic wave in heterogeneous partially saturated media can cause pore fluid pressure relaxation at mesoscopic scale, thereby making the fluid mobility inherently associated with poroelastic reflectivity. For two typical gas-brine reservoir models, with the given rock and fluid properties, the numerical analysis suggests that variations of patchy fluid saturation, fluid compressibility contrast, and acoustic stiffness of rock frame collectively affect the seismic reflection dependence on mobility. In particular, the realistic compressibility contrast of fluid patches in shallow and deep reservoir environments plays an important role in determining the reflection sensitivity to mobility. We also use a time-lapse seismic data set from a Steam-Assisted Gravity Drainage producing heavy oil reservoir to demonstrate that mobility change coupled with patchy saturation possibly leads to seismic spectral energy shifting from the baseline to monitor line. Our workflow starts from performing seismic spectral analysis on the targeted reflectivity interface. Then, on the basis of mesoscopic fluid pressure diffusion between patches of steam and heavy oil, poroelastic reflectivity modeling is conducted to understand the shift of the central frequency toward low frequencies after the steam injection. The presented results open the possibility of monitoring mobility change of a partially saturated geological formation from dissipation-related seismic attributes.

Apparently spontaneous fracture of a granitic exfoliation dome: observations and monitoring

NASA Astrophysics Data System (ADS)

Collins, B. D.; Stock, G. M.; Eppes, M. C.; Lewis, S. W.; Corbett, S.; Smith, J. B.

2016-12-01

Exfoliation sheet formation has attracted scientific attention for more than two centuries. Although a number of theories have been proposed, firm understanding of the cause of exfoliation has proved elusive, partly because observations of their formation are scarce. The 2014-2016 spontaneous exfoliation of Twain Harte Dome, located in the western foothills of California's Sierra Nevada Mesozoic granitic batholith, provides an unprecedented opportunity to study this phenomenon. Understanding such events can offer direct insight into similar exfoliating environments where spontaneous rock fracturing generates related geohazards such as rock falls. Twain Harte Dome fractured energetically on at least 5 occasions in August and September 2014, with slabs of rock thrust into the air 40 cm in a few seconds time and surficial fracture of rock occurring over a total area of 2,800 m2. Several of these events were witnessed first-hand and recorded by video. Additional (but non-energetic) cracking occurred during August 2015, followed by another energetic fracturing event in June 2016 over a much smaller (16 m2) area that again sent granite slabs airborne. No previous spontaneous exfoliation had been recorded here over the past 90 years and no obvious trigger (e.g., earthquake) occurred prior to the recent events. Using high-resolution topographic and fracture mapping, acoustic emission monitoring, and environmental monitoring, we show that these fracture events are correlated with hot summer periods - an indication that thermal stresses likely have an important role in causing exfoliation. Surface crackmeter, and subsurface borehole extensometer and rock bolt force measurements strengthen this relationship, with stresses and deformations spiking during hot summer afternoons. Our instrumentation data captured one of the exfoliation events and show that cumulative stress and deformation increases may have acted as precursor signals to the apparently spontaneous rock

Aquifers survey in the context of source rocks exploitation: from baseline acquisition to long term monitoring

NASA Astrophysics Data System (ADS)

Garcia, Bruno; Rouchon, Virgile; Deflandre, Jean-Pierre

2017-04-01

Producing hydrocarbons from source rocks (like shales: a mix of clays, silts, carbonate and sandstone minerals containing matured organic matter, i.e. kerogen oil and gas, but also non-hydrocarbon various species of chemical elements including sometimes radioactive elements) requires to create permeability within the rock matrix by at least hydraulically fracturing the source rock. It corresponds to the production of hydrocarbon fuels that have not been naturally expelled from the pressurized matured source rock and that remain trapped in the porosity or/and kerogen porosity of the impermeable matrix. Azimuth and extent of developed fractures can be respectively determined and mapped by monitoring the associated induced microseismicity. This allows to have an idea of where and how far injected fluids penetrated the rock formation. In a geological context, aquifers are always present in the vicinity -or on fluid migration paths- of such shale formations: deep aquifers (near the shale formation) up to sub-surface and potable (surface) aquifers. Our purpose will be to track any unsuitable invasion or migration of chemicals specifies coming from matured shales of production fluids including both drilling and fracturing ones into aquifers. Our objective is to early detect and alarm of any anomaly to avoid any important environmental issue. The approach consists in deploying a specific sampling tool within a well to recover formation fluids and to run a panoply of appropriate laboratory tests to state on fluid characteristics. Of course for deep aquifers, such a characterization process may consider aquifer properties prior producing shale oil and gas, as they may contain naturally some chemical species present in the source rocks. One can also consider that a baseline acquisition could be justified in case of possible previous invasion of non-natural fluids in the formation under survey (due to any anthropogenic action at surface or in the underground). The paper aims

A hazard and risk classification system for catastrophic rock slope failures in Norway

NASA Astrophysics Data System (ADS)

Hermanns, R.; Oppikofer, T.; Anda, E.; Blikra, L. H.; Böhme, M.; Bunkholt, H.; Dahle, H.; Devoli, G.; Eikenæs, O.; Fischer, L.; Harbitz, C. B.; Jaboyedoff, M.; Loew, S.; Yugsi Molina, F. X.

2012-04-01

The Geological Survey of Norway carries out systematic geologic mapping of potentially unstable rock slopes in Norway that can cause a catastrophic failure. As catastrophic failure we describe failures that involve substantial fragmentation of the rock mass during run-out and that impact an area larger than that of a rock fall (shadow angle of ca. 28-32° for rock falls). This includes therefore rock slope failures that lead to secondary effects, such as a displacement wave when impacting a water body or damming of a narrow valley. Our systematic mapping revealed more than 280 rock slopes with significant postglacial deformation, which might represent localities of large future rock slope failures. This large number necessitates prioritization of follow-up activities, such as more detailed investigations, periodic monitoring and permanent monitoring and early-warning. In the past hazard and risk were assessed qualitatively for some sites, however, in order to compare sites so that political and financial decisions can be taken, it was necessary to develop a quantitative hazard and risk classification system. A preliminary classification system was presented and discussed with an expert group of Norwegian and international experts and afterwards adapted following their recommendations. This contribution presents the concept of this final hazard and risk classification that should be used in Norway in the upcoming years. Historical experience and possible future rockslide scenarios in Norway indicate that hazard assessment of large rock slope failures must be scenario-based, because intensity of deformation and present displacement rates, as well as the geological structures activated by the sliding rock mass can vary significantly on a given slope. In addition, for each scenario the run-out of the rock mass has to be evaluated. This includes the secondary effects such as generation of displacement waves or landslide damming of valleys with the potential of later

The Rock that Hit New York

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meade, Roger Allen; Keksis, August Lawrence

On January 12, 1975, a rock seemed to fall from the sky over New York State’s Schoharie County hitting the tractor of a local farmer, who was “preparing his fields for spring planting.” As the farmer later described the event to a reporter from the UFO INVESTIGATOR, the object glanced off the tractor, fell to the ground, and melted its way through a patch of ice that was two and one half inches thick. The farmer, Leonard Tillapaugh, called the county sheriff, Harvey Stoddard, who recovered the rock, noting that it “was still warm.” Why and how a sample ofmore » the rock came to Los Alamos is not known. However, it captivated a wide Laboratory audience, was subjected to rigorous testing and evaluation. Los Alamos used the scientific method in the manner promoted by Hynek. Did Los Alamos solve the mystery of the rock’s origin? Not definitively. Although the exact origin could not be determined, it was shown conclusively that the rock was not from outer space. With that said, the saga of Rock that hit New York came to an end. Nothing more was said or written about it. The principals involved have long since passed from the scene. The NICAP ceased operations in 1980. And, the rock, itself, has disappeared.« less

Particle Size Reduction in Geophysical Granular Flows: The Role of Rock Fragmentation

NASA Astrophysics Data System (ADS)

Bianchi, G.; Sklar, L. S.

2016-12-01

Particle size reduction in geophysical granular flows is caused by abrasion and fragmentation, and can affect transport dynamics by altering the particle size distribution. While the Sternberg equation is commonly used to predict the mean abrasion rate in the fluvial environment, and can also be applied to geophysical granular flows, predicting the evolution of the particle size distribution requires a better understanding the controls on the rate of fragmentation and the size distribution of resulting particle fragments. To address this knowledge gap we are using single-particle free-fall experiments to test for the influence of particle size, impact velocity, and rock properties on fragmentation and abrasion rates. Rock types tested include granodiorite, basalt, and serpentinite. Initial particle masses and drop heights range from 20 to 1000 grams and 0.1 to 3.0 meters respectively. Preliminary results of free-fall experiments suggest that the probability of fragmentation varies as a power function of kinetic energy on impact. The resulting size distributions of rock fragments can be collapsed by normalizing by initial particle mass, and can be fit with a generalized Pareto distribution. We apply the free-fall results to understand the evolution of granodiorite particle-size distributions in granular flow experiments using rotating drums ranging in diameter from 0.2 to 4.0 meters. In the drums, we find that the rates of silt production by abrasion and gravel production by fragmentation scale with drum size. To compare these rates with free-fall results we estimate the particle impact frequency and velocity. We then use population balance equations to model the evolution of particle size distributions due to the combined effects of abrasion and fragmentation. Finally, we use the free-fall and drum experimental results to model particle size evolution in Inyo Creek, a steep, debris-flow dominated catchment, and compare model results to field measurements.

Testing New Techniques for Mars Rover Rock-Drilling

NASA Image and Video Library

2017-10-23

In the summer and fall of 2017, the team operating NASA's Curiosity Mars rover conducted tests in the "Mars Yard" at NASA's Jet Propulsion Laboratory, Pasadena, California, to develop techniques that Curiosity might be able to use to resume drilling into rocks on Mars. JPL robotics engineer Vladimir Arutyunov, in this June 29, 2017, photo, checks the test rover's drill bit at its contact point with a rock. Note that the stabilizer post visible to the right of the bit is not in contact with the rock, unlike the positioning used and photographed by Curiosity when drilling into rocks on Mars in 2013 to 2016. In late 2016, after Curiosity's drill had collected sample material from 15 Martian rocks, the drill's feed mechanism ceased working reliably. That motorized mechanism moved the bit forward or back with relation to the stabilizer posts on either side of the bit. In normal drilling by Curiosity, the stabilizers were positioned on the target rock first, and then the feed mechanism extended the rotation-percussion bit into the rock. In the alternative technique seen here, called "feed-extended drilling," the test rover's stabilizers are not used to touch the rock. The bit is advanced into the rock by motion of the robotic arm rather than the drill's feed mechanism. https://photojournal.jpl.nasa.gov/catalog/PIA22061

Five-year performance monitoring of a high-density polyethylene (HDPE) cover system at a reclaimed mine waste rock pile in the Sydney Coalfield (Nova Scotia, Canada).

PubMed

Power, Christopher; Ramasamy, Murugan; MacAskill, Devin; Shea, Joseph; MacPhee, Joseph; Mayich, David; Baechler, Fred; Mkandawire, Martin

2017-12-01

Cover systems are commonly placed over waste rock piles (WRPs) to limit atmospheric water and oxygen ingress and control the generation and release of acid mine drainage (AMD) to the receiving environment. Although covers containing geomembranes such as high-density polyethylene (HDPE) exhibit the attributes to be highly effective, there are few, if any, published studies monitoring their performance at full-scale WRPs. In 2011, a HDPE cover was installed over the Scotchtown Summit WRP in Nova Scotia, Canada, and extensive field performance monitoring was conducted over the next five years. A range of parameters within the atmosphere, cover, waste rock, groundwater and surface water, were monitored and integrated into a comprehensive hydrogeochemical conceptual model to assess (i) atmospheric ingress to the waste rock, (ii) waste rock acidity and depletion and (iii) evolution of groundwater and surface water quality. Results demonstrate that the cover is effective and meeting site closure objectives. Depletion in oxygen influx resulted in slower sulphide oxidation and AMD generation, while a significant reduction in water influx (i.e. 512 to 50 mm/year) resulted in diminished AMD release. Consistent improvements in groundwater quality (decrease in sulphate and metals; increase in pH) beneath and downgradient of the WRP were observed. Protection and/or significant improvement in surface water quality was evident in all surrounding watercourses due to the improved groundwater plume and elimination of contaminated runoff over previously exposed waste rock. A variably saturated flow and contaminant transport model is currently being developed to predict long-term cover system performance.

Virtual obstacle crossing: Reliability and differences in stroke survivors who prospectively experienced falls or no falls.

PubMed

Punt, Michiel; Bruijn, Sjoerd M; Wittink, Harriet; van de Port, Ingrid G; Wubbels, Gijs; van Dieën, Jaap H

2017-10-01

Stroke survivors often fall during walking. To reduce fall risk, gait testing and training with avoidance of virtual obstacles is gaining popularity. However, it is unknown whether and how virtual obstacle crossing is associated with fall risk. The present study assessed whether obstacle crossing characteristics are reliable and assessed differences in stroke survivors who prospectively experienced falls or no falls. We recruited twenty-nine community dwelling chronic stroke survivors. Participants crossed five virtual obstacles with increasing lengths. After a break, the test was repeated to assess test-retest reliability. For each obstacle length and trial, we determined; success rate, leading limb preference, pre and post obstacle distance, margins of stability, toe clearance, and crossing step length and speed. Subsequently, fall incidence was monitored using a fall calendar and monthly phone calls over a six-month period. Test-retest reliability was poor, but improved with increasing obstacle-length. Twelve participants reported at least one fall. No association of fall incidence with any of the obstacle crossing characteristics was found. Given the absence of height of the virtual obstacles, obstacle avoidance may have been relatively easy, allowing participants to cross obstacles in multiple ways, increasing variability of crossing characteristics and reducing the association with fall risk. These finding cast some doubt on current protocols for testing and training of obstacle avoidance in stroke rehabilitation. Copyright © 2017 Elsevier B.V. All rights reserved.

Energy Dissipating Devices in Falling Rock Protection Barriers

NASA Astrophysics Data System (ADS)

Castanon-Jano, L.; Blanco-Fernandez, E.; Castro-Fresno, D.; Ballester-Muñoz, F.

2017-03-01

Rockfall is a phenomenon which, when uncontrolled, may cause extensive material damage and personal injury. One of the structures used to avoid accidents caused by debris flows or rockfalls is flexible barriers. The energy dissipating devices which absorb the energy generated by rock impact and reduce the mechanical stresses in the rest of the elements of the structure are an essential part of these kinds of structures. This document proposes an overview of the performance of energy dissipating devices, as well as of the role that they fulfil in the barrier. Furthermore, a compilation and a description of the dissipating elements found in the literature are proposed. Additionally, an analysis has been performed of the aspects taken into account in the design, such as experimental (quasi-static and dynamic) tests observing the variation of the behaviour curve depending on the test speed and numerical simulations by means of several finite element software packages.

Fall hazard control observed on residential construction sites.

PubMed

Kaskutas, Vicki; Dale, Ann Marie; Nolan, James; Patterson, Dennis; Lipscomb, Hester J; Evanoff, Bradley

2009-06-01

Falls are a leading cause of mortality and morbidity in the construction industry. This study measured fall hazards at residential construction sites. Trained carpenters administered the St. Louis Audit of Fall Risks and interviewed carpenters. The prevalence of fall prevention practices meeting safety criteria was counted and correlations explored. We identified a high prevalence of fall hazards at the 197 residential sites audited. Roof sheathing met safety criteria most consistently (81%) and truss setting least consistently (28%). Use of personal fall arrest and monitoring of unguarded floor openings were rare. Safer performance on several scales was correlated. Construction sites of large-sized contractors were generally safer than smaller contractors. Apprentice carpenters were less familiar with their employers' fall prevention plan than experienced workers. Safety could be improved with consistent use of recognized fall prevention practices at residential construction sites.

Rock slope instabilities in Norway: First systematic hazard and risk classification of 22 unstable rock slopes

NASA Astrophysics Data System (ADS)

Böhme, Martina; Hermanns, Reginald L.; Oppikofer, Thierry; Penna, Ivanna

2016-04-01

Unstable rock slopes that can cause large failures of the rock-avalanche type have been mapped in Norway for almost two decades. Four sites have earlier been characterized as high-risk objects based on expertise of few researchers. This resulted in installing continuous monitoring systems and set-up of an early-warning system for those four sites. Other unstable rock slopes have not been ranked related to their hazard or risk. There are ca. 300 other sites known of which 70 sites were installed for periodic deformation measurements using multiple techniques (Global Navigation Satellite Systems, extensometers, measurement bolts, and others). In 2012 a systematic hazard and risk classification system for unstable rock slopes was established in Norway and the mapping approach adapted to that in 2013. Now, the first 22 sites were classified for hazard, consequences and risk using this classification system. The selection of the first group of sites to be classified was based on an assumed high hazard or risk and importance given to the sites by Norwegian media and the public. Nine of the classified 22 unstable rock slopes are large sites that deform inhomogeneously or are strongly broken up in individual blocks. This suggests that different failure scenarios are possible that need to be analyzed individually. A total of 35 failure scenarios for those nine unstable rock slopes were considered. The hazard analyses were based on 9 geological parameters defined in the classification system. The classification system will be presented based on the Gamanjunni unstable rock slope. This slope has a well developed back scarp that exposes 150 m preceding displacement. The lateral limits of the unstable slope are clearly visible in the morphology and InSAR displacement data. There have been no single structures observed that allow sliding kinematically. The lower extend of the displacing rock mass is clearly defined in InSAR data and by a zone of higher rock fall activity. Yearly

The analysis of creep characteristics of the surrounding rock of the carbonaceous rock tunnel based on Singh-Mitchell model

NASA Astrophysics Data System (ADS)

Luo, Junhui; Mi, Decai; Ye, Qiongyao; Deng, Shengqiang; Zeng, Fuquan; Zeng, Yongjun

2018-01-01

Carbonaceous rock has the characteristics of easy disintegration, softening, swelling and environmental sensitivity, which belongs to soft surrounding rock, and the deformation during excavation and long-term stability of the surrounding rock of carbonaceous rock tunnel are common problems in the construction of carbonaceous rock tunnel. According to the above, the Monitor and measure the displacement, temperature and osmotic pressure of the surrounding carbonaceous rock of the tunnel of Guangxi Hebai highway. Then it based on the obtaining data to study the creep mechanism of surrounding rock using Singh-Mitchell model and predict the deformation of surrounding rock before the tunnel is operation. The results show that the Singh-Mitchell creep model can effectively analyse and predict the deformation development law of surrounding rock of tunnel without considering temperature and osmotic pressure, it can provide reference for the construction of carbonaceous rock tunnel and the measures to prevent and reinforce it..

The "Aachen fall prevention App" - a Smartphone application app for the self-assessment of elderly patients at risk for ground level falls.

PubMed

Rasche, Peter; Mertens, Alexander; Bröhl, Christina; Theis, Sabine; Seinsch, Tobias; Wille, Matthias; Pape, Hans-Christoph; Knobe, Matthias

2017-01-01

Fall incidents are a major problem for patients and healthcare. The "Aachen Fall Prevention App" (AFPA) represents the first mobile Health (mHealth) application (app) empowering older patients (persons 50+ years) to self-assess and monitor their individual fall risk. Self-assessment is based on the "Aachen Fall Prevention Scale," which consists of three steps. First, patients answer ten standardized yes-no questions (positive criterion ≥ 5 "Yes" responses). Second, a ten-second test of free standing without compensatory movement is performed (positive criterion: compensatory movement). Finally, during the third step, patients rate their subjective fall risk on a 10-point Likert scale, based on the results of steps one and two. The purpose of this app is (1) to offer a low-threshold service through which individuals can independently monitor their individual fall risk and (2) to collect data about how a patient-centered mHealth app for fall risk assessment is used in the field. The results represent the first year of an ongoing field study. From December 2015 to December 2016, 197 persons downloaded the AFPA (iOS ™ and Android ™ ; free of charge). N  = 111 of these persons voluntarily shared their data and thereby participated in the field study. Data from a final number of n  = 79 persons were analyzed due to exclusion criteria (age, missing objective fall risk, missing self-assessment). The objective fall risk and the self-assessed subjective risk measured by the AFPA showed a significant positive relationship. The "Aachen Fall Prevention App" (AFPA) is an mHealth app released for iOS and Android. This field study revealed the AFPA as a promising tool to raise older adults' awareness of their individual fall risk by means of a low-threshold patient-driven fall risk assessment tool.

Water resources of the Salmon Falls Creek basin, Idaho-Nevada

USGS Publications Warehouse

Crosthwaite, E.G.

1969-01-01

The northern part of the Salmon Falls Creek basin, referred to as the Salmon Falls tract, contains a large acreage of good agricultural land, but the surface-water supply is inadequate to develop the area fully. Attempts to develop ground water for irrigation have been successful only locally. Specific capacities of wells drilled for irrigation and for test purposes ranged from less than 0.5 to 70 gallons per minute per foot of drawdown. The surface-water supply averages 107,000 acre-feet annually, of which about 76,000 acre-feet is diverted for irrigation. The Idavada Volcanics, the most widespread and oldest water-bearing formation in the Salmon Falls tract, consists of massive, dense, thick flows and blankets of welded silicic tuff with associated fine- to coarse-grained ash, clay, silt, sand, and gravel. Fault zones and jointed rock yield large amounts of water to wells, but massive nonjointed units yield little water. Sand, tuff, and ash beds yield moderate quantities of water. Clay, sandy clay, sand, and pea gravel occur in topographic lows on the Idavada Volcanics. The finegrained sediments yield little water to wells, but the gravel yields moderate quantities. Vesicular porphyritic irregularly jointed olivine basalt flows, which overlie the Idavada Volcanics, underlie almost all the Salmon Falls tract. Lenticular fine-grained sedimentary beds as much as 15 feet thick separate some of the flows. Joints and contacts between flows yield small to moderate amounts of water to wells. Alluvial and windblown deposits blanket most of the tract. Where they occur below the water table, the alluvial deposits yield adequate supplies for stock and domestic wells. Perched water in the alluvium along Deep Creek supplies some stock and domestic wells during most years. Ground-water supplies adequate for domestic and stock use can be obtained everywhere in the tract, but extensive exploration has discovered only five local areas where pumping ground water for irrigation is

Longitudinal falls data in Parkinson's disease: feasibility of fall diaries and effect of attrition.

PubMed

Hunter, Heather; Rochester, Lynn; Morris, Rosie; Lord, Sue

2017-06-02

Identifying causes of falls for people with Parkinson's disease has met with limited success. Prospective falls measurement using the "gold standard" approach is challenging. This paper examines the process and outcomes associated with longitudinal falls reporting in this population. Participants were recruited from ICICLE-GAIT (a collaborative study with ICICLE-PD; an incident cohort study). Monthly falls diaries were examined over 48 months for accuracy of data and rate of attrition. To further inform analysis, characteristics of participants with 36-month completed diaries were compared with those who did not complete diaries. One hundred and twenty-one participants were included at baseline. By 12 months, falls diary data had reduced to 107 participants; to 81 participants by 36 months; and to 59 participants by 48 months. Key reasons for diary attrition were withdrawal from ICICLE-gait (n = 16) (13.2%), and noncompliance (n = 11) (9.1%). The only significant difference between the completed and non-completed diary groups was age at 36 months, with older participants being more likely to send in diaries. Prospective falls data is feasible to collect over the long term. Attrition rates are high; however, participants retained in the study are overall representative of the total falls diary cohort. Implications for Rehabilitation Understanding falls evolution in Parkinson's disease through consistent, personalized monitoring of falls events is critical to inform effective management. Our study shows that it is feasible to collect longitudinal falls data using "gold standard" methodology, although significant resources are required for implementation. We anticipate that our study methodology is broadly applicable to any at-risk falls cohort including older adults and diverse neurological conditions. Researchers and clinicians collating prospective falls data must ensure that participants understand what constitutes a fall, as per the World Health

RadNet Air Data From Idaho Falls, ID

EPA Pesticide Factsheets

This page presents radiation air monitoring and air filter analysis data for Idaho Falls, ID from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

The relationship of intrinsic fall risk factors to a recent history of falling in older women with osteoporosis.

PubMed

Arnold, Cathy M; Busch, Angela J; Schachter, Candice L; Harrison, Liz; Olszynski, Wojciech

2005-07-01

Cross-sectional descriptive analysis investigating intrinsic fall risk factors in postmenopausal women with osteoporosis. To examine the relationships between history of recent falls and balance, pain, quality of life, function, posture, strength, and mobility. Women with osteoporosis who fall are at a high risk of fracture due to decreased bone strength. Identifying fall risk factors for older women with osteoporosis is a crucial step in decreasing the incidence of falls and fracture. METHOD AND MEASURES: Seventy-three women over 60 years of age with established osteoporosis participated in comprehensive testing of fall history, physical function, and quality of life. Significant correlations were found between a recent history of falls and degree of kyphosis (r = 0.29), fear of falls/emotional status (r = -0.27), and balance (r = -0.27). Degree of kyphosis and fear of falls/emotional status explained 20% of the variance of recent fall history using binary logistic regression. Women with an increased kyphosis were more likely to have had a recent fall (odds ratio [OR], 1.17; 95% CI, 1.03-1.34) and those with better emotional status and less fear of falling were less likely to have had a recent fall (OR, 0.61; 95% CI, 0.38-0.97). Increased thoracic kyphosis and fear of falling are 2 intrinsic factors associated with recent falls in women with osteoporosis. To design more effective interventions to decrease fall risk in this population, future prospective, longitudinal studies should monitor kyphosis, fear of falling, balance reactions, and other potential risk factors not identified in this study.

After the Fall: A Conflict Management Program to Foster Open Society

ERIC Educational Resources Information Center

Shapiro, Daniel L.

2004-01-01

The fall of the Berlin Wall rocked the sociopolitical equilibrium of eastern and central Europe. Communism lost its grip over much of Europe. The USSR, Yugoslavia, and Czechoslovakia divided along ethnic, religious, and historical lines. Ethnopolitical tensions surfaced across the region, and in Yugoslavia, tensions combusted. Whereas democracy…

Hydraulic fracture monitoring in hard rock at 410 m depth with an advanced fluid-injection protocol and extensive sensor array

NASA Astrophysics Data System (ADS)

Zang, Arno; Stephansson, Ove; Stenberg, Leif; Plenkers, Katrin; Specht, Sebastian; Milkereit, Claus; Schill, Eva; Kwiatek, Grzegorz; Dresen, Georg; Zimmermann, Günter; Dahm, Torsten; Weber, Michael

2017-02-01

In this paper, an underground experiment at the Äspö Hard Rock Laboratory (HRL) is described. Main goal is optimizing geothermal heat exchange in crystalline rock mass at depth by multistage hydraulic fracturing with minimal impact on the environment, that is, seismic events. For this, three arrays with acoustic emission, microseismicity and electromagnetic sensors are installed mapping hydraulic fracture initiation and growth. Fractures are driven by three different water injection schemes (continuous, progressive and pulse pressurization). After a brief review of hydraulic fracture operations in crystalline rock mass at mine scale, the site geology and the stress conditions at Äspö HRL are described. Then, the continuous, single-flow rate and alternative, multiple-flow rate fracture breakdown tests in a horizontal borehole at depth level 410 m are described together with the monitoring networks and sensitivity. Monitoring results include the primary catalogue of acoustic emission hypocentres obtained from four hydraulic fractures with the in situ trigger and localizing network. The continuous versus alternative water injection schemes are discussed in terms of the fracture breakdown pressure, the fracture pattern from impression packer result and the monitoring at the arrays. An example of multistage hydraulic fracturing with several phases of opening and closing of fracture walls is evaluated using data from acoustic emissions, seismic broad-band recordings and electromagnetic signal response. Based on our limited amount of in situ tests (six) and evaluation of three tests in Ävrö granodiorite, in the multiple-flow rate test with progressively increasing target pressure, the acoustic emission activity starts at a later stage in the fracturing process compared to the conventional fracturing case with continuous water injection. In tendency, also the total number and magnitude of acoustic events are found to be smaller in the progressive treatment with

Characterization and monitoring of the Séchilienne rock slope using 3D imaging methods (Isère, France)

NASA Astrophysics Data System (ADS)

Vulliez, Cindy; Guerin, Antoine; Abellán, Antonio; Derron, Marc-Henri; Jaboyedoff, Michel; Chanut, Marie-Aurélie; Dubois, Laurent; Duranthon, Jean-Paul

2016-04-01

The Séchilienne landslide located in the Romanche Valley (Isère, France) is a well instrumented mass movements of about 650 m high and 250 m wide, with a potential volume of about 3 million m3 in the most active part (Duranthon and Effendiantz, 2004 ; Kasperski et al., 2010). The slope, which is mainly composed of micaschist, is characterized by the presence of a NE-SW sub-vertical fracturing system involved in the destabilization of the area. The rock slope has been continuously moving since the eighties decade, with a growing acceleration during the period 2009-2013 followed by a progressive stabilization during the last years. The monitoring of the active part of the rock slide is currently carried out by an instrumentation system in order to prevent a large failure. In this work, we used different 3D techniques in order to monitor the whole rock slide displacements in three dimensions, as follows: (a) First of all, we used a Terrestrial Laser Scanning to obtain high resolution point clouds (8 cm point spacing) of the rock slope geometry. Nine different fieldwork campaigns were performed during the last six years, as follows: Aug. 2009, Jul. 2010, Nov. 2011, Nov. 2012, Jun. and Nov. 2013, Jul. and Oct. 2014, May 2015, which provided a set of 3D representations of the rock slope topography over time; (b) In addition, we used three Helicopter-based Laser Scanning campaigns carried out in Jan. 2011, Feb. 2012 and Mar. 2014 acquired by the Cerema (Chanut et al., 2014); (c) Finally, more than 600 photos were taken in Apr. 2015 in order to build a photogrammetric model of the area using Structure-from-Motion (SfM) workflow in Agisoft PhotoScan software. All types of data were complementary for the study of the movement and allowed us having a good spatial vision of the evolution of the most active part of the slope. A detailed structural analysis was performed from both LiDAR and SfM point clouds using Coltop3D (Jaboyedoff et al., 2007). Eight joint sets were

Rock-Fluid Interactions Under Stress: How Rock Microstructure Controls The Evolution of Porosity and Permeability

NASA Astrophysics Data System (ADS)

Vanorio, T.

2016-12-01

Monitoring chemo-mechanical processes geophysically — e.g., fluid disposal or storage, thermal and chemical stimulation of reservoirs, or natural fluids simply entering a new system in the subsurface— raises numerous concerns because of the likelihood of fluid-rock chemical interactions and our limited ability to decipher the geophysical signature of coupled processes. One of the missing links is coupling the evolution of porosity, permeability, and velocity of rocks together with reactive transport, since rocks deform and their microstructure evolves, as a result of chemical reactions under stress. This study describes recent advances in rock-physics experiments to understand the effects of dissolution-induced compaction on acoustic velocity, porosity, and permeability. Data observation includes time-lapse experiments and imaging tracking transport and elastic properties, the rock microstructure, and the pH and chemical composition of the fluid permeating the rock. Results show that the removal of high surface area, mineral phases such as microcrystalline calcite and clay appears to be mostly responsible for dissolution-induced compaction. Nevertheless, it is the original rock microstructure and its response to stress that ultimately defines how solution-transfer and rock compaction feed back upon each other. This work has a dual aim: understanding the mechanisms underlying permanent modifications to the rock microstructure and providing a richer set of experimental information to inform the formulation of new simulations and rock modeling.

Measurement of rock mass deformation with grouted coaxial antenna cables

NASA Astrophysics Data System (ADS)

Dowding, C. H.; Su, M. B.; O'Connor, K.

1989-01-01

Techniques presented herein show how reflected voltage pulses from coaxial antenna cable grouted in rock masses can be employed to quantify the type and magnitude of rock mass deformation. This measurement is similar to that obtained from a combined full profile extensometer (to measure local extension) and inclinometer (to measure local shearing). Rock mass movements deform the grouted cable, which locally changes cable capacitance and thereby the reflected wave form of the voltage pulse. Thus, by monitoring changes in these reflection signatures, it is possible to monitor rock mass deformation. This paper presents laboratory measurements necessary to quantitatively interpret the reflected voltage signatures. Cables were sheared and extended to correlate measured cable deformation with reflected voltage signals. Laboratory testing included development of grout mixtures with optimum properties for field installation and performance of a TDR (Time Domain Reflectometry) monitoring system. Finally, the interpretive techniques developed through laboratory measurements were applied to previously collected field data to extract hitherto unrealized information.

The Geothermic Fatigue Hydraulic Fracturing Experiment in Äspö Hard Rock Laboratory, Sweden: New Insights Into Fracture Process through In-situ AE Monitoring

NASA Astrophysics Data System (ADS)

Kwiatek, G.; Plenkers, K.; Zang, A.; Stephansson, O.; Stenberg, L.

2016-12-01

The geothermic Fatigue Hydraulic Fracturing (FHF) in situ experiment (Nova project 54-14-1) took place in the Äspö Hard Rock Laboratory/Sweden in a 1.8 Ma old granitic to dioritic rock mass. The experiment aims at optimizing geothermal heat exchange in crystalline rock mass by multistage hydraulic fracturing at 10 m scale. Six fractures are driven by three different water injection schemes (continuous, cyclic, pulse pressurization) inside a 28 m long, horizontal borehole at depth level 410 m. The rock volume subject to hydraulic fracturing and monitored by three different networks with acoustic emission (AE), micro-seismicity and electromagnetic sensors is about 30 m x 30 m x 30 m in size. The 16-channel In-situ AE monitoring network by GMuG monitored the rupture generation and propagation in the frequency range 1000 Hz to 100,000 Hz corresponding to rupture dimensions from cm- to dm-scale. The in-situ AE monitoring system detected and analyzed AE activity in-situ (P- and S-wave picking, localization). The results were used to review the ongoing microfracturing activity in near real-time. The in-situ AE monitoring network successfully recorded and localized 196 seismic events for most, but not all, hydraulic fractures. All AE events detected in-situ occurred during fracturing time periods. The source parameters (fracture sizes, moment magnitudes, static stress drop) of AE events framing injection periods were calculated using the combined spectral fitting/spectra ratio techniques. The AE activity is clustered in space and clearly outline the fractures location, its orientation, and expansion as well as their temporal evolution. The outward migration of AE events away from the borehole is observed. Fractures extend up to 7 m from the injection interval in the horizontal borehole. The fractures orientation and location correlate for most fractures roughly with the results gained by image packer. Clear differences in seismic response between hydraulic fractures in

Unmanned Aerial Systems and DSM matching for rock glacier monitoring

NASA Astrophysics Data System (ADS)

Dall'Asta, Elisa; Forlani, Gianfranco; Roncella, Riccardo; Santise, Marina; Diotri, Fabrizio; Morra di Cella, Umberto

2017-05-01

Among other techniques, aerial and terrestrial photogrammetry have long been used to control the displacements of landslides and glaciers as well as for the detection of terrain morphological changes. Unmanned Aerial Systems (UAS) are today an efficient tool to perform data acquisition in rough or difficult terrain, both safely and quickly, avoiding hazards and risks for the operators while at the same time containing the survey costs. Since 2012 ARPAVdA (the Regional Environmental Protection Agency of Aosta Valley, Italy) periodically surveys with UAS photogrammetry the Gran Sometta rock glacier, the Agency main monitoring site for the climate change impacts on high-mountain areas and related infrastructures. A Digital Surface Model (DSM) and an orthophoto of the rock glacier are produced after each survey flight. In order to accurately georeference them in a stable reference system, a Global Navigation Satellite System (GNSS) campaign is carried out at each epoch, to update the coordinates of signalised Ground Control Points (GCPs), since they partly lay in unstable (moving) areas. In late August 2015 a survey flight has been executed with a senseFly eBee RTK, with differential corrections sent from a ground reference station. The block has been adjusted without GCP using, as control information, only the projection centres coordinates encoded in the images. The RMS of the differences found on twelve Check Points were about 4 cm in horizontal and 7 cm in elevation, i.e. practically the same accuracy found using GCP. Differences between the DSMs produced at the same epoch with block orientation performed with GCP and with GNSS-determined projection centres were also investigated. To evaluate the rock glacier displacement fields between two epochs, corresponding features were at first manually identified on the orthophotos by a trained operator. To avoid the manual time-consuming procedure and increase the density of displacement information, two automatic

Study of the Rock Mass Failure Process and Mechanisms During the Transformation from Open-Pit to Underground Mining Based on Microseismic Monitoring

NASA Astrophysics Data System (ADS)

Zhao, Yong; Yang, Tianhong; Bohnhoff, Marco; Zhang, Penghai; Yu, Qinglei; Zhou, Jingren; Liu, Feiyue

2018-05-01

To quantitatively understand the failure process and failure mechanism of a rock mass during the transformation from open-pit mining to underground mining, the Shirengou Iron Mine was selected as an engineering project case study. The study area was determined using the rock mass basic quality classification method and the kinematic analysis method. Based on the analysis of the variations in apparent stress and apparent volume over time, the rock mass failure process was analyzed. According to the recent research on the temporal and spatial change of microseismic events in location, energy, apparent stress, and displacement, the migration characteristics of rock mass damage were studied. A hybrid moment tensor inversion method was used to determine the rock mass fracture source mechanisms, the fracture orientations, and fracture scales. The fracture area can be divided into three zones: Zone A, Zone B, and Zone C. A statistical analysis of the orientation information of the fracture planes orientations was carried out, and four dominant fracture planes were obtained. Finally, the slip tendency analysis method was employed, and the unstable fracture planes were obtained. The results show: (1) The microseismic monitoring and hybrid moment tensor analysis can effectively analyze the failure process and failure mechanism of rock mass, (2) during the transformation from open-pit to underground mining, the failure type of rock mass is mainly shear failure and the tensile failure is mostly concentrated in the roof of goafs, and (3) the rock mass of the pit bottom and the upper of goaf No. 18 have the possibility of further damage.

Albeni Falls Wildlife Mitigation : Annual Report 2002.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terra-Berns, Mary

The Albeni Falls Interagency Work Group continued to actively engage in implementing wildlife mitigation actions in 2002. Regular Work Group meetings were held to discuss budget concerns affecting the Albeni Falls Wildlife Mitigation Program, to present potential acquisition projects, and to discuss and evaluate other issues affecting the Work Group and Project. Work Group members protected 1,386.29 acres of wildlife habitat in 2002. To date, the Albeni Falls project has protected approximately 5,914.31 acres of wildlife habitat. About 21% of the total wildlife habitat lost has been mitigated. Administrative activities have increased as more properties are purchased and continue tomore » center on restoration, operation and maintenance, and monitoring. In 2001, Work Group members focused on development of a monitoring and evaluation program as well as completion of site-specific management plans. This year the Work Group began implementation of the monitoring and evaluation program performing population and plant surveys, data evaluation and storage, and map development as well as developing management plans. Assuming that the current BPA budget restrictions will be lifted in the near future, the Work Group expects to increase mitigation properties this coming year with several potential projects.« less

GlacierRocks - Glacier-Headwall Interaction and its Influence on Rockfall Activity

NASA Astrophysics Data System (ADS)

Hartmeyer, Ingo; Keuschnig, Markus; Krautblatter, Michael; Helfricht, Kay; Leith, Kerry; Otto, Jan-Christoph

2017-04-01

Climate models predict continued climate warming and a decrease of Austrian glaciers to less than 20% of their present area by the end of this century. Rockfall from freshly exposed headwalls has been documented as an increasing risk factor with considerable significance for man and high-alpine infrastructure. Recent findings of a five-year terrestrial laserscanning campaign (2011-2016) monitoring glacial headwalls at the Kitzsteinhorn (3.203 m a.s.l.), Hohe Tauern Range, Austria, show the dramatic impact of glacier thinning on adjacent headwalls: 80 % of the detected rockfall volumes were triggered from areas located less than 20 m above the current glacier surface. Despite these implications, little is known about the thermal, mechanical and hydrological processes that operate at the glacier-headwall interface (randkluft). Systemic in-situ monitoring of stability-relevant parameters are lacking, leaving fundamental gaps in the understanding of rockfall preconditioning in glacial headwalls and the geomorphological evolution of glaciated catchments. In this contribution we introduce the recently approved research project 'GlacierRocks', which starts in 2017 and will run for at least three years. 'GlacierRocks' will establish the worldwide first research site for long-term monitoring of stability-relevant processes inside a randkluft system. Based on the acquired monitoring data 'GlacierRocks' is pursuing three overall aims at (1) gaining a better understanding of rockfall preconditioning in randklufts and related geomorphological shaping of headwalls, (2) analyzing poorly understood glacial thinning dynamics near headwalls, and (3) estimating present and future rockfall hazard potential in headwalls on a regional scale. The three system components (headwall, glacier, randkluft) will be investigated by combining geomorphological, glaciological and meteorological methods. 'GlacierRocks' will continuously monitor rock temperature, rock moisture, frost cracking

Large rock avalanches triggered by the M 7.9 Denali Fault, Alaska, earthquake of 3 November 2002

USGS Publications Warehouse

Jibson, R.W.; Harp, E.L.; Schulz, W.; Keefer, D.K.

2006-01-01

The moment magnitude (M) 7.9 Denali Fault, Alaska, earthquake of 3 November 2002 triggered thousands of landslides, primarily rock falls and rock slides, that ranged in volume from rock falls of a few cubic meters to rock avalanches having volumes as great as 20 ?? 106 m3. The pattern of landsliding was unusual: the number and concentration of triggered slides was much less than expected for an earthquake of this magnitude, and the landslides were concentrated in a narrow zone about 30-km wide that straddled the fault-rupture zone over its entire 300-km length. Despite the overall sparse landslide concentration, the earthquake triggered several large rock avalanches that clustered along the western third of the rupture zone where acceleration levels and ground-shaking frequencies are thought to have been the highest. Inferences about near-field strong-shaking characteristics drawn from interpretation of the landslide distribution are strikingly consistent with results of recent inversion modeling that indicate that high-frequency energy generation was greatest in the western part of the fault-rupture zone and decreased markedly to the east. ?? 2005 Elsevier B.V. All rights reserved.

Assessments of Potential Rock Coatings at Rocknest, Gale Crater with ChemCam

NASA Technical Reports Server (NTRS)

Blaney, D. L.; Anderson, R.; Berger, G.; Bridges, J.; Bridges, N.; Clark, B.; Clegg, S.; Ehlman, B.; Goetz, W.; King, P.;

Exploring the feasibility and acceptability of sensor monitoring of gait and falls in the homes of persons with multiple sclerosis.

PubMed

Newland, Pamela; Wagner, Joanne M; Salter, Amber; Thomas, Florian P; Skubic, Marjorie; Rantz, Marilyn

2016-09-01

Gait parameters variability and falls are problems for persons with MS and have not been adequately captured in the home. Our goal was to explore the feasibility and acceptability of monitoring of gait and falls in the homes of persons with MS over a period of 30 days. To test the feasibility of measuring gait and falls for 30days in the home of persons with MS, spatiotemporal gait parameters stride length, stride time, and gait speed were compared. A 3D infrared depth imaging system has been developed to objectively measure gait and falls in the home environment. Participants also completed a 16-foot GaitRite electronic pathway walk to validate spatiotemporal parameters of gait (gait speed (cm/s), stride length (cm), and gait cycle time(s)) during the timed 25 foot walking test (T25FWT). We also documented barriers to feasibility of installing the in-home sensors for these participants. The results of the study suggest that the Kinect sensor may be used as an alternative device to measure gait for persons with MS, depending on the desired accuracy level. Ultimately, using in-home sensors to analyze gait parameters in real time is feasible and could lead to better analysis of gait in persons with MS. Copyright © 2016 Elsevier B.V. All rights reserved.

The river and the rocks: The geologic story of Great Falls and the Potomac River Gorge

USGS Publications Warehouse

Reed, John Calvin; Sigafoos, Robert Sumner; Fisher, George Wescott

1980-01-01

Visitors to Great Falls now number close to a half million annually and, because of this continuing and mounting interest, the U.S. Geological Survey has joined with the National Park Service in preparing this booklet for better understanding and enjoyment of the Great Falls of the Potomac River.

Cardiovascular Assessment of Falls in Older People

PubMed Central

Tan, Maw Pin; Kenny, Rose Anne

2006-01-01

Falls in older people can be caused by underlying cardiovascular disorders, either because of balance instability in persons with background gait and balance disorders, or because of amnesia for loss of consciousness during unwitnessed syncope. Pertinent investigations include a detailed history, 12-lead electrocardiography, lying and standing blood pressure, carotid sinus massage (CSM), head-up tilt, cardiac electrophysiological tests, and ambulatory blood pressure and heart rate monitoring, which includes external and internal cardiac monitoring. The presence of structural heart disease predicts an underlying cardiac cause. Conversely, the absence of either indicates that neurally mediated etiology is likely. CSM and tilt-table testing should be considered in patients with unexplained and recurrent falls. Holter monitoring over 24 hours has a low diagnostic yield. Early use of an implantable loop recorder may be more cost-effective. A dedicated investigation unit increases the likelihood of achieving positive diagnoses and significantly reduces hospital stay and health expenditure. PMID:18047258

Mapping of hydrothermally altered rocks using airborne multispectral scanner data, Marysvale, Utah, mining district

USGS Publications Warehouse

Podwysocki, M.H.; Segal, D.B.; Jones, O.D.

1983-01-01

Multispectral data covering an area near Marysvale, Utah, collected with the airborne National Aeronautics and Space Administration (NASA) 24-channel Bendix multispectral scanner, were analyzed to detect areas of hydrothermally altered, potentially mineralized rocks. Spectral bands were selected for analysis that approximate those of the Landsat 4 Thematic Mapper and which are diagnostic of the presence of hydrothermally derived products. Hydrothermally altered rocks, particularly volcanic rocks affected by solutions rich in sulfuric acid, are commonly characterized by concentrations of argillic minerals such as alunite and kaolinite. These minerals are important for identifying hydrothermally altered rocks in multispectral images because they have intense absorption bands centered near a wavelength of 2.2 ??m. Unaltered volcanic rocks commonly do not contain these minerals and hence do not have the absorption bands. A color-composite image was constructed using the following spectral band ratios: 1.6??m/2.2??m, 1.6??m/0.48??m, and 0.67??m/1.0??m. The particular bands were chosen to emphasize the spectral contrasts that exist for argillic versus non-argillic rocks, limonitic versus nonlimonitic rocks, and rocks versus vegetation, respectively. The color-ratio composite successfully distinguished most types of altered rocks from unaltered rocks. Some previously unrecognized areas of hydrothermal alteration were mapped. The altered rocks included those having high alunite and/or kaolinite content, siliceous rocks containing some kaolinite, and ash-fall tuffs containing zeolitic minerals. The color-ratio-composite image allowed further division of these rocks into limonitic and nonlimonitic phases. The image did not allow separation of highly siliceous or hematitically altered rocks containing no clays or alunite from unaltered rocks. A color-coded density slice image of the 1.6??m/2.2??m band ratio allowed further discrimination among the altered units. Areas

Respirable dust measured downwind during rock dust application.

PubMed

Harris, M L; Organiscak, J; Klima, S; Perera, I E

2017-05-01

The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

RadNet Air Data From Little Rock, AR

EPA Pesticide Factsheets

This page presents radiation air monitoring and air filter analysis data for Little Rock, AR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

Tectonic constraints on a deep-seated rock slide in weathered crystalline rocks

NASA Astrophysics Data System (ADS)

Borrelli, Luigi; Gullà, Giovanni

2017-08-01

Deep-seated rock slides (DSRSs), recognised as one of the most important mass wasting processes worldwide, involve large areas and cause several consequences in terms of environmental and economic damage; they result from a complex of controlling features and processes. DSRSs are common in Calabria (southern Italy) where the complex geo-structural setting plays a key role in controlling the geometry of the failure surface and its development. This paper describes an integrated multi-disciplinary approach to investigate a DSRS in Palaeozoic high-grade metamorphic rocks of the Sila Massif; it focuses on the definition of the internal structure and the predisposing factors of the Serra di Buda landslide near the town of Acri, which is a paradigm for numerous landslides in this area. An integrated interdisciplinary study based on geological, structural, and geomorphological investigations-including field observations of weathering grade of rocks, minero-petrographic characterisations, geotechnical investigations and, in particular, fifteen years of displacement monitoring-is presented. Stereoscopic analysis of aerial photographs and field observations indicate that the Serra di Buda landslide consists of two distinct compounded bodies: (i) an older and dormant body ( 7 ha) and (ii) a more recent and active body ( 13 ha) that overlies the previous one. The active landslide shows movement linked to a deep-seated translational rock slide (block slide); the velocity scale ranges from slow (1.6 m/year during paroxysmal stages) to extremely slow (< 16 mm/year during stable creep stages). The geological structures and rock weathering have played a key role in the landslide's initiation and further development. Steep slope angles, rugged topography, river deepening and erosion at the toe of the slope are also responsible for the formation of this landslide. In particular, the landslide shows a strongly tectonic constraint: the flanks are bounded by high-angle faults, and the

Lunar highland rock types: Their implications for impact-induced fractionation

NASA Technical Reports Server (NTRS)

Phinney, W. C.; Warner, J. L.; Simonds, C. H.

1977-01-01

Lunar rocks may be classified into three major groups: (1) coarse-grained igneous rocks, (2) fine-grained igneous rocks, and (3) breccias. Group 1 is interpreted as primitive lunar crustal rocks that display various degrees of crushing and/or annealing. Group 2 is interpreted as volcanic rocks. Group 3 is interpreted as resulting from impacts on the lunar surface and is subdivided on the basis of matrix textures into fragmental breccias, crystalline breccias that have been annealed, and crystalline breccias with igneous matrices. A synthesis of the data concerning lunar highlands polymict breccias compels the prediction that the breccias should have homogeneous matrices from rock to rock within regions of the highlands of limited size where impact mixing has been efficient and extensive. But the returned breccias, even from one landing site, display a wide range in composition. This incompatibility between prediction and observation is a paradox that may be resolved by a process that acts after impact mixing to cause a differentiation of the breccia compositions. Partial melting of the local average crustal composition (as modeled by the average soil composition for each site) and separation of melt and residue in ejecta and/or fall-back blankets are compatible with the reviewed data and may resolve the paradox.

Stability of Large Parallel Tunnels Excavated in Weak Rocks: A Case Study

NASA Astrophysics Data System (ADS)

Ding, Xiuli; Weng, Yonghong; Zhang, Yuting; Xu, Tangjin; Wang, Tuanle; Rao, Zhiwen; Qi, Zufang

2017-09-01

Diversion tunnels are important structures for hydropower projects but are always placed in locations with less favorable geological conditions than those in which other structures are placed. Because diversion tunnels are usually large and closely spaced, the rock pillar between adjacent tunnels in weak rocks is affected on both sides, and conventional support measures may not be adequate to achieve the required stability. Thus, appropriate reinforcement support measures are needed, and the design philosophy regarding large parallel tunnels in weak rocks should be updated. This paper reports a recent case in which two large parallel diversion tunnels are excavated. The rock masses are thin- to ultra-thin-layered strata coated with phyllitic films, which significantly decrease the soundness and strength of the strata and weaken the rocks. The behaviors of the surrounding rock masses under original (and conventional) support measures are detailed in terms of rock mass deformation, anchor bolt stress, and the extent of the excavation disturbed zone (EDZ), as obtained from safety monitoring and field testing. In situ observed phenomena and their interpretation are also included. The sidewall deformations exhibit significant time-dependent characteristics, and large magnitudes are recorded. The stresses in the anchor bolts are small, but the extents of the EDZs are large. The stability condition under the original support measures is evaluated as poor. To enhance rock mass stability, attempts are made to reinforce support design and improve safety monitoring programs. The main feature of these attempts is the use of prestressed cables that run through the rock pillar between the parallel tunnels. The efficacy of reinforcement support measures is verified by further safety monitoring data and field test results. Numerical analysis is constantly performed during the construction process to provide a useful reference for decision making. The calculated deformations are in

Integration of ambient seismic noise monitoring, displacement and meteorological measurements to infer the temperature-controlled long-term evolution of a complex prone-to-fall cliff

NASA Astrophysics Data System (ADS)

Colombero, C.; Baillet, L.; Comina, C.; Jongmans, D.; Larose, E.; Valentin, J.; Vinciguerra, S.

2018-06-01

Monitoring the temporal evolution of resonance frequencies and velocity changes detected from ambient seismic noise recordings can help in recognizing reversible and irreversible modifications within unstable rock volumes. With this aim, the long-term ambient seismic noise data set acquired at the potentially unstable cliff of Madonna delSasso (NW Italian Alps) was analysed in this study, using both spectral analysis and cross-correlation techniques. Noise results were integrated and compared with direct displacement measurements and meteorological data, to understand the long-term evolution of the cliff. No irreversible modifications in the stability of the site were detected over the monitored period. Conversely, daily and seasonal air temperature fluctuations were found to control resonance frequency values, amplitudes and directivities and to induce reversible velocity changes within the fractured rock mass. The immediate modification in the noise parameters due to temperature fluctuations was interpreted as the result of rock mass thermal expansion and contraction, inducing variations in the contact stiffness along the fractures isolating two unstable compartments. Differences with previous case studies were highlighted in the long-term evolution of noise spectral amplitudes and directivities, due to the complex 3-D fracture setting of the site and to the combined effects of the two unstable compartments.

Landslides caused by the Klamath Falls, Oregon, earthquakes of September 20, 1993

USGS Publications Warehouse

Keefer, D.K.; Schuster, R.L.

1993-01-01

In the Klamath Falls area, the most numerous earthquake-induced rock falls were along the east-to southeast-facing flank of a ridge immediately south and west of Howard Bay (locality 1 on the accompanying map), 18 km east-southeast of the epicenter of the magntiude 6.0 shock at 10:45 p.m. This ridge is more than 240 m high and has slopes steeper than 45° in places. The upper part of the ridge is composed of material from basaltic lava flows, an the lower slopes are covered with colluvium and talus deposits containing abundant boulders. 

Cost-effectiveness of a day hospital falls prevention programme for screened community-dwelling older people at high risk of falls.

PubMed

Irvine, Lisa; Conroy, Simon P; Sach, Tracey; Gladman, John R F; Harwood, Rowan H; Kendrick, Denise; Coupland, Carol; Drummond, Avril; Barton, Garry; Masud, Tahir

2010-11-01

multifactorial falls prevention programmes for older people have been proved to reduce falls. However, evidence of their cost-effectiveness is mixed. economic evaluation alongside pragmatic randomised controlled trial. randomised trial of 364 people aged ≥70, living in the community, recruited via GP and identified as high risk of falling. Both arms received a falls prevention information leaflet. The intervention arm were also offered a (day hospital) multidisciplinary falls prevention programme, including physiotherapy, occupational therapy, nurse, medical review and referral to other specialists. self-reported falls, as collected in 12 monthly diaries. Levels of health resource use associated with the falls prevention programme, screening (both attributed to intervention arm only) and other health-care contacts were monitored. Mean NHS costs and falls per person per year were estimated for both arms, along with the incremental cost-effectiveness ratio (ICER) and cost effectiveness acceptability curve. in the base-case analysis, the mean falls programme cost was £349 per person. This, coupled with higher screening and other health-care costs, resulted in a mean incremental cost of £578 for the intervention arm. The mean falls rate was lower in the intervention arm (2.07 per person/year), compared with the control arm (2.24). The estimated ICER was £3,320 per fall averted. the estimated ICER was £3,320 per fall averted. Future research should focus on adherence to the intervention and an assessment of impact on quality of life.

Automatic segmentation of triaxial accelerometry signals for falls risk estimation.

PubMed

Redmond, Stephen J; Scalzi, Maria Elena; Narayanan, Michael R; Lord, Stephen R; Cerutti, Sergio; Lovell, Nigel H

2010-01-01

Falls-related injuries in the elderly population represent one of the most significant contributors to rising health care expense in developed countries. In recent years, falls detection technologies have become more common. However, very few have adopted a preferable falls prevention strategy through unsupervised monitoring in the free-living environment. The basis of the monitoring described herein was a self-administered directed-routine (DR) comprising three separate tests measured by way of a waist-mounted triaxial accelerometer. Using features extracted from the manually segmented signals, a reasonable estimate of falls risk can be achieved. We describe here a series of algorithms for automatically segmenting these recordings, enabling the use of the DR assessment in the unsupervised and home environments. The accelerometry signals, from 68 subjects performing the DR, were manually annotated by an observer. Using the proposed signal segmentation routines, an good agreement was observed between the manually annotated markers and the automatically estimated values. However, a decrease in the correlation with falls risk to 0.73 was observed using the automatic segmentation, compared to 0.81 when using markers manually placed by an observer.

Investigation of Non-Linear Dynamics of the Rock Massive,Using Seismological Catalogue data and Induction Electromagnetic Monitoring Data in a Rock Burst Mine.

NASA Astrophysics Data System (ADS)

Hachay, O. A.; Khachay, O. Y.; Klimko, V. K.; Shipeev, O. V.

2012-04-01

Geological medium is an open dynamical system, which is influenced on different scales by natural and man-made impacts, which change the medium state and lead as a result to a complicated many ranked hierarchic evolution. That is the subject of geo synergetics. Paradigm of physical mesomechanics, which was advanced by academician Panin V.E. and his scientific school, which includes the synergetic approach is a constructive method for research and changing the state of heterogenic materials [1]. That result had been obtained on specimens of different materials. In our results of research of no stationary geological medium in a frame of natural experiments in real rock massifs, which are under high man-made influence it was shown, that the state dynamics can be revealed with use synergetics in hierarchic medium. Active and passive geophysical monitoring plays a very important role for research of the state of dynamical geological systems. It can be achieved by use electromagnetic and seismic fields. Our experience of that research showed the changing of the system state reveals on the space scales and times in the parameters, which are linked with the peculiarities of the medium of the second or higher ranks [2-5]. Results of seismological and electromagnetic information showed the mutual additional information on different space-time levels of rock massive state, which are energetic influenced by explosions, used in mining technology. It is revealed a change of nonlinearity degree in time of the massive state by active influence on it. The description of massive movement in a frame of linear dynamical system does not satisfy the practical situation. The received results are of great significance because for the first time we could find the coincidences with the mathematical theory of open systems and experimental natural results with very complicated structure. On that base we developed a new processing method for the seismological information which can be used in

Modelling rock fragmentation of Extremely Energetic Rockfalls

NASA Astrophysics Data System (ADS)

De Blasio, Fabio; Dattola, Giuseppe; Battista Crosta, Giovanni

2017-04-01

Extremely energetic rockfalls (EER) are phenomena for which the combination of a large volume (at least some thousands of m ) and a free fall height of hundreds of metres, results in a large released energy. We fix a threshold value of around 1/50 of kilotons to define such a type of events. Documented examples include several events with dif-ferent size in the Alps (Dru, 2005, 2011, 265,000, 59,200 m3; val Fiscalina - Cima Una, 2007, 40,000 m3; Thurwieser 2004, ca 2 Mm3; Cengalo, 2011, 1.5*105 m3 in 2016, in Switzerland; Civetta, 2013, ca 50,000 m3;), in the Apennines (Gran Sasso, 2006, 30,000 m3), Rocky Mountains (Yosemite, Happy Isles, 38,000 m3), and Himalaya. EERs may become more frequent on steep and sharp mountain peaks as a consequence of permafrost thawing at higher altitudes. In contrast to low energy rockfalls where block disintegration is limited, in EERs the impact after free fall causes an immediate and efficient release of energy much like an explosion. The severe disintegration of the rock and the corresponding air blast are capable of snapping trees many hundreds of metres ahead of the fall area. Pulverized rock at high speed can abrade tree logs, and the resulting suspension flow may travel much further the impact zone, blanketing vast surrounding areas. Using both published accounts of some of these events and collecting direct data for some of them, we present some basic models to describe the involved processes based on analogies with explosions and explosive fragmentation. Of the initial energy, one part is used up in the rock disintegration, and the rest is shared between the shock wave and air blast. The fragmentation energy is calculated based on the fitting of the dust size spectrum by using different proba-bilistic distribution laws and the definition of a surface energy and by considering the involved strain rate. We find the fragmentation is around one third of the initial boulder energy. Finally, we evaluate the velocity of the

Using remotely sensed imagery and GIS to monitor and research salmon spawning: A case study of the Hanford Reach fall chinook (Oncorhynchus Tshawytscha)

DOE Office of Scientific and Technical Information (OSTI.GOV)

RH Visser

2000-03-16

The alteration of ecological systems has greatly reduced salmon populations in the Pacific Northwest. The Hanford Reach of the Columbia River, for example, is a component of the last ecosystem in eastern Washington State that supports a relatively healthy population of fall chinook salmon ([Oncorhynchus tshawytscha], Huntington et al. 1996). This population of fall chinook may function as a metapopulation for the Mid-Columbia region (ISG 1996). Metapopulations can seed or re-colonize unused habitat through the mechanism of straying (spawning in non-natal areas) and may be critical to the salmon recovery process if lost or degraded habitat is restored (i.e., themore » Snake, Upper Columbia, and Yakima rivers). For these reasons, the Hanford Reach fall chinook salmon population is extremely important for preservation of the species in the Columbia River Basin. Because this population is important to the region, non-intrusive techniques of analysis are essential for researching and monitoring population trends and spawning activities.« less

Wearable technology and ECG processing for fall risk assessment, prevention and detection.

PubMed

Melillo, Paolo; Castaldo, Rossana; Sannino, Giovanna; Orrico, Ada; de Pietro, Giuseppe; Pecchia, Leandro

2015-01-01

Falls represent one of the most common causes of injury-related morbidity and mortality in later life. Subjects with cardiovascular disorders (e.g., related to autonomic dysfunctions and postural hypotension) are at higher risk of falling. Autonomic dysfunctions increasing the risk of falling in the short and mid-term could be assessed by Heart Rate Variability (HRV) extracted by electrocardiograph (ECG). We developed three trials for assessing the usefulness of ECG monitoring using wearable devices for: risk assessment of falling in the next few weeks; prevention of imminent falls due to standing hypotension; and fall detection. Statistical and data-mining methods are adopted to develop classification and regression models, validated with the cross-validation approach. The first classifier based on HRV features enabled to identify future fallers among hypertensive patients with an accuracy of 72% (sensitivity: 51.1%, specificity: 80.2%). The regression model to predict falls due to orthostatic dropdown from HRV recorded before standing achieved an overall accuracy of 80% (sensitivity: 92%, specificity: 90%). Finally, the classifier to detect simulated falls using ECG achieved an accuracy of 77.3% (sensitivity: 81.8%, specificity: 72.7%). The evidence from these three studies showed that ECG monitoring and processing could achieve satisfactory performances compared to other system for risk assessment, fall prevention and detection. This is interesting as differently from other technologies actually employed to prevent falls, ECG is recommended for many other pathologies of later life and is more accepted by senior citizens.

Altered tuffaceous rocks of the Green River Formation in the Piceance Creek Basin, Colorado

USGS Publications Warehouse

Griggs, Roy Lee

1968-01-01

More than 50 ash-fall tuff beds which have altered to analcitized or feldspathized rocks have been found in the upper 500-600 feet of the Parachute Creek Member of the Green River Formation in the Piceance Creek Basin of northwestern Colorado. Similarly altered water-washed tuff occurs as tongues in the uppermost part of this member, and forms most of the lower 400-600 feet of the overlying Evacuation Creek Member of the Green River Formation. 'The altered ash-fall beds of the Parachute Creek Member are all thin and show a characteristic pattern of alteration. Most beds range in thickness from a fraction of an inch to a few inches. One bed reaches a maximum thickness of 5 feet, and, unlike the other beds, is composed of several successive ash falls. The pattern of alteration changes from the outer part to the center of the basin. Most beds in the outer part of the basin contain about 50 to 65 percent analcite,with the interstices between the crystals filled mainly by microlites of feldspar, opal, and quartz, and small amounts of carbonate. At the center of the basin .essentially all the beds -are composed of microlites of feldspar, opal, and quartz, and small amounts of carbonate. The tongues of water-washed tuff in the uppermost part of the Parachute Creek Member and the similar rocks composing the lower 400-600 feet of the Evacuation Creek Mewber are feldspathized rocks composed mainly of microlites of feldspar, opal, and quartz, varying amounts of carbonate, and in some specimens tiny subrounded crystals of analcite. The general trend in alteration of the tuffaceous rocks from analcitization near the margin to feidspathization near the center of the Piceance Creek Basin is believed to have taken place at shallow depth during diagenesis , as indicated by field observations and laboratory work. It is believed that during sedimentation and diagenesis the waters of the central part of the basin were more alkaline and following the breakdown of the original

Tertiary volcanic and hypabyssal rocks in the Ugashik quadrangle: A section in Geological Survey research 1981

USGS Publications Warehouse

,

1982-01-01

Potassium-argon dating of volcanic and hypabyssal rocks from the Ugashik quadrangle by F. H. Wilson and Nora Shew indicates that these rocks fall into the same two age groupings as those of the Chignik and Sutwik Island quadrangles to the south. Rocks of late Eocene to earliest Miocene and latest Miocene to Holocene age are found in both areas. Preliminary mapping by R. L. Detterman, J. E. Case, and F. H. Wilson indicates a major break in the trend to the west. This offset occurs in the vicinity of Wide and Puale Bays.

In-home fall risk assessment and detection sensor system.

PubMed

Rantz, Marilyn J; Skubic, Marjorie; Abbott, Carmen; Galambos, Colleen; Pak, Youngju; Ho, Dominic K C; Stone, Erik E; Rui, Liyang; Back, Jessica; Miller, Steven J

2013-07-01

Falls are a major problem in older adults. A continuous, unobtrusive, environmentally mounted (i.e., embedded into the environment and not worn by the individual), in-home monitoring system that automatically detects when falls have occurred or when the risk of falling is increasing could alert health care providers and family members to intervene to improve physical function or manage illnesses that may precipitate falls. Researchers at the University of Missouri Center for Eldercare and Rehabilitation Technology are testing such sensor systems for fall risk assessment (FRA) and detection in older adults' apartments in a senior living community. Initial results comparing ground truth (validated measures) of FRA data and GAITRite System parameters with data captured from Microsoft(®) Kinect and pulse-Doppler radar are reported. Copyright 2013, SLACK Incorporated.

Testing of a long-term fall detection system incorporated into a custom vest for the elderly.

PubMed

Bourke, Alan K; van de Ven, Pepijn W J; Chaya, Amy E; OLaighin, Gearóid M; Nelson, John

2008-01-01

A fall detection system and algorithm, incorporated into a custom designed garment has been developed. The developed fall detection system uses a tri-axial accelerometer to detect impacts and monitor posture. This sensor is attached to a custom designed vest, designed to be worn by the elderly person under clothing. The fall detection algorithm was developed and incorporates both impact and posture detection capability. The vest and fall algorithm was tested by two teams of 5 elderly subjects who wore the sensor system in turn for 2 week each and were monitored for 8 hours a day. The system previously achieved sensitivity of >90% and a specificity of >99%, using young healthy subjects performing falls and normal activities of daily living (ADL). In this study, over 833 hours of monitoring was performed over the course of the four weeks from the elderly subjects, during normal daily activity. In this time no actual falls were recorded, however the system registered a total of the 42 fall-alerts however only 9 were received at the care taker site. A fall detection system incorporated into a custom designed garment has been developed which will help reduce the incidence of the long-lie, when falls occur in the elderly population. However further development is required to reduce the number of false-positives and improve the transmission of messages.

Characterization of the 3-D fracture setting of an unstable rock mass: From surface and seismic investigations to numerical modeling

NASA Astrophysics Data System (ADS)

Colombero, C.; Baillet, L.; Comina, C.; Jongmans, D.; Vinciguerra, S.

2017-08-01

The characterization of the fracturing state of a potentially unstable rock cliff is a crucial requirement for stability assessments and mitigation purposes. Classical measurements of fracture location and orientation can however be limited by inaccessible rock exposures. The steep topography and high-rise morphology of these cliffs, together with the widespread presence of fractures, can additionally condition the success of geophysical prospecting on these sites. In order to mitigate these limitations, an innovative approach combining noncontact geomechanical measurements, active and passive seismic surveys, and 3-D numerical modeling is proposed in this work to characterize the 3-D fracture setting of an unstable rock mass, located in NW Italian Alps (Madonna del Sasso, VB). The 3-D fracture geometry was achieved through a combination of field observations and noncontact geomechanical measurements on oriented pictures of the cliff, resulting from a previous laser-scanning and photogrammetric survey. The estimation of fracture persistence within the rock mass was obtained from surface active seismic surveys. Ambient seismic noise and earthquakes recordings were used to assess the fracture control on the site response. Processing of both data sets highlighted the resonance properties of the unstable rock volume decoupling from the stable massif. A finite element 3-D model of the site, including all the retrieved fracture information, enabled both validation and interpretation of the field measurements. The integration of these different methodologies, applied for the first time to a complex 3-D prone-to-fall mass, provided consistent information on the internal fracturing conditions, supplying key parameters for future monitoring purposes and mitigation strategies.

Low-Impact Flooring: Does It Reduce Fall-Related Injuries?

PubMed

Hanger, H Carl

2017-07-01

To compare fall rates and injuries from falls on low-impact flooring (LIF) compared with a standard vinyl flooring. Prospective, observational, nonrandomized controlled study. Subacute Older Persons Health ward (N = 20 beds). Older inpatients. Three different types of LIF. All falls in the ward were prospectively monitored using incident reporting, noting location and consequences of each fall. Fall rates (per 1000 bed days) and injuries, were compared between bedroom falls on LIF against those occurring on standard vinyl flooring (controls). Over 31 months, there were 278 bedroom falls (from 178 fallers). The bedroom fall rate (falls per 1000 bed days occupied) did not differ between the LIF and control groups (median 15 [IQR 8-18] versus 17 [IQR 9-23], respectively; P = .47). However, fall-related injuries were significantly less frequent when they occurred on LIFs (22% of falls versus 34% of falls on control flooring; P = .02). Fractures occurred in 0.7% of falls in the LIF cohort versus 2.3% in the control cohort. Rolling resistance when moving heavier equipment, such as beds or hoists, was an issue for staff on LIF. LIF significantly reduced fall-related injuries compared with a standard vinyl flooring, whereas they did not alter the overall risk of falling. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Real-time monitoring system for elderly people in detecting falling movement using accelerometer and gyroscope

NASA Astrophysics Data System (ADS)

Siregar, B.; Andayani, U.; Bahri, R. P.; Seniman; Fahmi, F.

2018-03-01

Most of the elderly people is experiencing a decrease in physical quality, especially the weakness in the legs. This will cause elderly easy to fall and can have a serious impact on their health if not getting help very quickly. It is, therefore, necessary to take immediate action against the falling cases experienced by the elderly. One such action is by developing supervision and detecting of falling movements in real-time, which is then the connection to a member of the family. In this research, we used Arduino Uno as a microcontroller, sensor accelerometer, and gyroscope that serves to measure falling movement of the elderly person and supported by GPS technology Ublox Neo 6M to provide information about coordinates. The result was the high accuracy of delivering notification data to server and accuracy of data delivery to family notification equal to 93,75%. The system successfully detects the direction of falling: forward, backward, left or right and able to distinguish between unintentional falling and conscious falling like a bow or prostrate position.

Friction falls towards zero in quartz rock as slip velocity approaches seismic rates.

PubMed

Di Toro, Giulio; Goldsby, David L; Tullis, Terry E

2004-01-29

An important unsolved problem in earthquake mechanics is to determine the resistance to slip on faults in the Earth's crust during earthquakes. Knowledge of coseismic slip resistance is critical for understanding the magnitude of shear-stress reduction and hence the near-fault acceleration that can occur during earthquakes, which affects the amount of damage that earthquakes are capable of causing. In particular, a long-unresolved problem is the apparently low strength of major faults, which may be caused by low coseismic frictional resistance. The frictional properties of rocks at slip velocities up to 3 mm s(-1) and for slip displacements characteristic of large earthquakes have been recently simulated under laboratory conditions. Here we report data on quartz rocks that indicate an extraordinary progressive decrease in frictional resistance with increasing slip velocity above 1 mm s(-1). This reduction extrapolates to zero friction at seismic slip rates of approximately 1 m s(-1), and appears to be due to the formation of a thin layer of silica gel on the fault surface: it may explain the low strength of major faults during earthquakes.

Falling-incident detection and throughput enhancement in a multi-camera video-surveillance system.

PubMed

Shieh, Wann-Yun; Huang, Ju-Chin

2012-09-01

For most elderly, unpredictable falling incidents may occur at the corner of stairs or a long corridor due to body frailty. If we delay to rescue a falling elder who is likely fainting, more serious consequent injury may occur. Traditional secure or video surveillance systems need caregivers to monitor a centralized screen continuously, or need an elder to wear sensors to detect falling incidents, which explicitly waste much human power or cause inconvenience for elders. In this paper, we propose an automatic falling-detection algorithm and implement this algorithm in a multi-camera video surveillance system. The algorithm uses each camera to fetch the images from the regions required to be monitored. It then uses a falling-pattern recognition algorithm to determine if a falling incident has occurred. If yes, system will send short messages to someone needs to be noticed. The algorithm has been implemented in a DSP-based hardware acceleration board for functionality proof. Simulation results show that the accuracy of falling detection can achieve at least 90% and the throughput of a four-camera surveillance system can be improved by about 2.1 times. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.

Integrating technical rock climbing into protected area management: a case example of Minnewaska State Park Preserve, New York State

Treesearch

Jennifer A. Cairo; Thomas L. Cobb

1998-01-01

In the fall of 1996, technical rock climbing was introduced as a regulated outdoor recreation activity in Minnewaska State Park Preserve, situated in the Shawangunk Mountain region of New York State. It is the first instance in which rock climbing has been sanctioned by the New York State Office of Parks, Recreation and Historic Preservation. This paper identifies key...

Accelerometer and Camera-Based Strategy for Improved Human Fall Detection.

PubMed

Zerrouki, Nabil; Harrou, Fouzi; Sun, Ying; Houacine, Amrane

2016-12-01

In this paper, we address the problem of detecting human falls using anomaly detection. Detection and classification of falls are based on accelerometric data and variations in human silhouette shape. First, we use the exponentially weighted moving average (EWMA) monitoring scheme to detect a potential fall in the accelerometric data. We used an EWMA to identify features that correspond with a particular type of fall allowing us to classify falls. Only features corresponding with detected falls were used in the classification phase. A benefit of using a subset of the original data to design classification models minimizes training time and simplifies models. Based on features corresponding to detected falls, we used the support vector machine (SVM) algorithm to distinguish between true falls and fall-like events. We apply this strategy to the publicly available fall detection databases from the university of Rzeszow's. Results indicated that our strategy accurately detected and classified fall events, suggesting its potential application to early alert mechanisms in the event of fall situations and its capability for classification of detected falls. Comparison of the classification results using the EWMA-based SVM classifier method with those achieved using three commonly used machine learning classifiers, neural network, K-nearest neighbor and naïve Bayes, proved our model superior.

Time-Dependent Damage Investigation of Rock Mass in an In Situ Experimental Tunnel

PubMed Central

Jiang, Quan; Cui, Jie; Chen, Jing

2012-01-01

In underground tunnels or caverns, time-dependent deformation or failure of rock mass, such as extending cracks, gradual rock falls, etc., are a costly irritant and a major safety concern if the time-dependent damage of surrounding rock is serious. To understand the damage evolution of rock mass in underground engineering, an in situ experimental testing was carried out in a large belowground tunnel with a scale of 28.5 m in width, 21 m in height and 352 m in length. The time-dependent damage of rock mass was detected in succession by an ultrasonic wave test after excavation. The testing results showed that the time-dependent damage of rock mass could last a long time, i.e., nearly 30 days. Regression analysis of damage factors defined by wave velocity, resulted in the time-dependent evolutional damage equation of rock mass, which corresponded with logarithmic format. A damage viscoelastic-plastic model was developed to describe the exposed time-dependent deterioration of rock mass by field test, such as convergence of time-dependent damage, deterioration of elastic modules and logarithmic format of damage factor. Furthermore, the remedial measures for damaged surrounding rock were discussed based on the measured results and the conception of damage compensation, which provides new clues for underground engineering design.

A multi-modal approach for activity classification and fall detection

NASA Astrophysics Data System (ADS)

Castillo, José Carlos; Carneiro, Davide; Serrano-Cuerda, Juan; Novais, Paulo; Fernández-Caballero, Antonio; Neves, José

2014-04-01

The society is changing towards a new paradigm in which an increasing number of old adults live alone. In parallel, the incidence of conditions that affect mobility and independence is also rising as a consequence of a longer life expectancy. In this paper, the specific problem of falls of old adults is addressed by devising a technological solution for monitoring these users. Video cameras, accelerometers and GPS sensors are combined in a multi-modal approach to monitor humans inside and outside the domestic environment. Machine learning techniques are used to detect falls and classify activities from accelerometer data. Video feeds and GPS are used to provide location inside and outside the domestic environment. It results in a monitoring solution that does not imply the confinement of the users to a closed environment.

[Intelligent videosurveillance and falls detection: Perceptions of professionals and managers].

PubMed

Lapierre, Nolwenn; Carpentier, Isabelle; St-Arnaud, Alain; Ducharme, Francine; Meunier, Jean; Jobidon, Mireille; Rousseau, Jacqueline

2016-02-01

Gerontechnologies can be used to detect accidental falls. However, existing systems do not entirely meet users' expectations. Our team developed an intelligent video-monitoring systems to fill these gaps. Authors advocate consulting potential users at the early stages of the design of gerontechnologies and integrating their suggestions. This study aims to explore health care workers' opinion regarding the intelligent video monitoring to detect falls by older adults living at home. This qualitative study explored the opinions of 31 participants using focus groups. Transcripts were analyzed using predetermined codes based on the competence model. Participants reported several advantages for using the intelligent video monitoring and provided suggestions for improving its use. The participants' suggestions and comments will help to improve the system and match it to users' needs. © CAOT 2015.

The PARAChute Project: Remote Monitoring of Posture and Gait for Fall Prevention

NASA Astrophysics Data System (ADS)

Hewson, David J.; Duchêne, Jacques; Charpillet, François; Saboune, Jamal; Michel-Pellegrino, Valérie; Amoud, Hassan; Doussot, Michel; Paysant, Jean; Boyer, Anne; Hogrel, Jean-Yves

2007-12-01

Falls in the elderly are a major public health problem due to both their frequency and their medical and social consequences. In France alone, more than two million people aged over 65 years old fall each year, leading to more than 9 000 deaths, in particular in those over 75 years old (more than 8 000 deaths). This paper describes the PARAChute project, which aims to develop a methodology that will enable the detection of an increased risk of falling in community-dwelling elderly. The methods used for a remote noninvasive assessment for static and dynamic balance assessments and gait analysis are described. The final result of the project has been the development of an algorithm for movement detection during gait and a balance signature extracted from a force plate. A multicentre longitudinal evaluation of balance has commenced in order to validate the methodologies and technologies developed in the project.

Automated Technology for In-home Fall Risk Assessment and Detection Sensor System

PubMed Central

Rantz, Marilyn J.; Skubic, Marjorie; Abbott, Carmen; Galambos, Colleen; Pak, Youngju; Ho, Dominic K.C.; Stone, Erik E.; Rui, Liyang; Back, Jessica; Miller, Steven J.

2013-01-01

Falls are a major problem for older adults. A continuous, unobtrusive, environmentally mounted in-home monitoring system that automatically detects when falls have occurred or when the risk of falling is increasing could alert health care providers and family members so they could intervene to improve physical function or mange illnesses that are precipitating falls. Researchers at the University of Missouri (MU)Center for Eldercare and Rehabilitation Technology are testing such sensor systems for fall risk assessment and detection in older adults’ apartments in a senior living community. Initial results comparing ground truth fall risk assessment data and GAITRite gait parameters with gait parameters captured from Mircosoft Kinect and Pulse-Dopplar radar are reported. PMID:23675644

Evaluation of an inpatient fall risk screening tool to identify the most critical fall risk factors in inpatients.

PubMed

Hou, Wen-Hsuan; Kang, Chun-Mei; Ho, Mu-Hsing; Kuo, Jessie Ming-Chuan; Chen, Hsiao-Lien; Chang, Wen-Yin

2017-03-01

monitored by nurses to prevent falling during hospitalisations. © 2016 John Wiley & Sons Ltd.

Scattering from Rock and Rock Outcrops

DTIC Science & Technology

2015-09-30

Scattering from Rock and Rock Outcrops Derek R. Olson The Pennsylvania State University Applied Research Laboratory, P.O. Box 30 State...In terms of target detection and classification, scattering from exposed rock on the seafloor, (i.e., individual rocks and rock outcrops) presents...levels, and other statistical measures of acoustic scattering from rocks and rock outcrops is therefore critical. Unfortunately (and curiously

Automatic pattern identification of rock moisture based on the Staff-RF model

NASA Astrophysics Data System (ADS)

Zheng, Wei; Tao, Kai; Jiang, Wei

2018-04-01

Studies on the moisture and damage state of rocks generally focus on the qualitative description and mechanical information of rocks. This method is not applicable to the real-time safety monitoring of rock mass. In this study, a musical staff computing model is used to quantify the acoustic emission signals of rocks with different moisture patterns. Then, the random forest (RF) method is adopted to form the staff-RF model for the real-time pattern identification of rock moisture. The entire process requires only the computing information of the AE signal and does not require the mechanical conditions of rocks.

Radiocarbon as a Reactive Tracer for Tracking Permanent CO 2 Storage in Basaltic Rocks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matter, Juerg; Stute, Martin; Schlosser, Peter

In view of concerns about the long-term integrity and containment of CO 2 storage in geologic reservoirs, many efforts have been made to improve the monitoring, verification and accounting methods for geologically stored CO 2. Our project aimed to demonstrate that carbon-14 ( 14C) could be used as a reactive tracer to monitor geochemical reactions and evaluate the extent of mineral trapping of CO 2 in basaltic rocks. The capacity of a storage reservoir for mineral trapping of CO 2 is largely a function of host rock composition. Mineral carbonation involves combining CO 2 with divalent cations including Ca 2+,more » Mg 2+ and Fe 2+. The most abundant geological sources for these cations are basaltic rocks. Based on initial storage capacity estimates, we know that basalts have the necessary capacity to store million to billion tons of CO 2 via in situ mineral carbonation. However, little is known about CO2-fluid-rock reactions occurring in a basaltic storage reservoir during and post-CO 2 injection. None of the common monitoring and verification techniques have been able to provide a surveying tool for mineral trapping. The most direct method for quantitative monitoring and accounting involves the tagging of the injected CO 2 with 14C because 14C is not present in deep geologic reservoirs prior to injection. Accordingly, we conducted two CO 2 injection tests at the CarbFix pilot injection site in Iceland to study the feasibility of 14C as a reactive tracer for monitoring CO 2-fluid-rock reactions and CO 2 mineralization. Our newly developed monitoring techniques, using 14C as a reactive tracer, have been successfully demonstrated. For the first time, permanent and safe disposal of CO 2 as environmentally benign carbonate minerals in basaltic rocks could be shown. Over 95% of the injected CO 2 at the CarbFix pilot injection site was mineralized to carbonate minerals in less than two years after injection. Our monitoring results confirm that CO 2 mineralization in

Rockfall monitoring by Terrestrial Laser Scanning - case study of the basaltic rock face at Castellfollit de la Roca (Catalonia, Spain)

NASA Astrophysics Data System (ADS)

Abellán, A.; Vilaplana, J. M.; Calvet, J.; García-Sellés, D.; Asensio, E.

2011-03-01

This case study deals with a rock face monitoring in urban areas using a Terrestrial Laser Scanner. The pilot study area is an almost vertical, fifty meter high cliff, on top of which the village of Castellfollit de la Roca is located. Rockfall activity is currently causing a retreat of the rock face, which may endanger the houses located at its edge. TLS datasets consist of high density 3-D point clouds acquired from five stations, nine times in a time span of 22 months (from March 2006 to January 2008). The change detection, i.e. rockfalls, was performed through a sequential comparison of datasets. Two types of mass movement were detected in the monitoring period: (a) detachment of single basaltic columns, with magnitudes below 1.5 m3 and (b) detachment of groups of columns, with magnitudes of 1.5 to 150 m3. Furthermore, the historical record revealed (c) the occurrence of slab failures with magnitudes higher than 150 m3. Displacements of a likely slab failure were measured, suggesting an apparent stationary stage. Even failures are clearly episodic, our results, together with the study of the historical record, enabled us to estimate a mean detachment of material from 46 to 91.5 m3 year-1. The application of TLS considerably improved our understanding of rockfall phenomena in the study area.

Objective fall risk detection in stroke survivors using wearable sensor technology: a feasibility study.

PubMed

Taylor-Piliae, Ruth E; Mohler, M Jane; Najafi, Bijan; Coull, Bruce M

2016-12-01

Stroke survivors often have persistent neural deficits related to motor function and sensation, which increase their risk of falling, most of which occurs at home or in community settings. The use of wearable technology to monitor fall risk and gait in stroke survivors may prove useful in enhancing recovery and/or preventing injuries. Determine the feasibility of using wearable technology (PAMSys™) to objectively monitor fall risk and gait in home and community settings in stroke survivors. In this feasibility study, we used the PAMSys to identify fall risk indicators (postural transitions: duration in seconds, and number of unsuccessful attempts), and gait (steps, speed, duration) for 48 hours during usual daily activities in stroke survivors (n = 10) compared to age-matched controls (n = 10). A questionnaire assessed device acceptability. Stroke survivors mean age was 70 ± 8 years old, were mainly Caucasian (60%) women (70%), and not significantly different than the age-matched controls (all P-values >0.20). Stroke survivors (100%) reported that the device was comfortable to wear, didn't interfere with everyday activities, and were willing to wear it for another 48 hours. None reported any difficulty with the device while sleeping, removing/putting back on for showering or changing clothes. When compared to controls, stroke survivors had significantly worse fall risk indicators and walked less (P < 0.05). Stroke survivors reported high acceptability of 48 hours of continuous PAMSys monitoring. The use of in-home wearable technology may prove useful in monitoring fall risk and gait in stroke survivors, potentially enhancing recovery.

Soil Rock Analyzer

NASA Technical Reports Server (NTRS)

1985-01-01

A redesigned version of a soil/rock analyzer developed by Martin Marietta under a Langley Research Center contract is being marketed by Aurora Tech, Inc. Known as the Aurora ATX-100, it has self-contained power, an oscilloscope, a liquid crystal readout, and a multichannel spectrum analyzer. It measures energy emissions to determine what elements in what percentages a sample contains. It is lightweight and may be used for mineral exploration, pollution monitoring, etc.

Automated field detection of rock fracturing, microclimate, and diurnal rock temperature and strain fields

NASA Astrophysics Data System (ADS)

Warren, K.; Eppes, M.-C.; Swami, S.; Garbini, J.; Putkonen, J.

2013-11-01

The rates and processes that lead to non-tectonic rock fracture on Earth's surface are widely debated but poorly understood. Few, if any, studies have made the direct observations of rock fracturing under natural conditions that are necessary to directly address this problem. An instrumentation design that enables concurrent high spatial and temporal monitoring resolution of (1) diurnal environmental conditions of a natural boulder and its surroundings in addition to (2) the fracturing of that boulder under natural full-sun exposure is described herein. The surface of a fluvially transported granite boulder was instrumented with (1) six acoustic emission (AE) sensors that record micro-crack associated, elastic wave-generated activity within the three-dimensional space of the boulder, (2) eight rectangular rosette foil strain gages to measure surface strain, (3) eight thermocouples to measure surface temperature, and (4) one surface moisture sensor. Additionally, a soil moisture probe and a full weather station that measures ambient temperature, relative humidity, wind speed, wind direction, barometric pressure, insolation, and precipitation were installed adjacent to the test boulder. AE activity was continuously monitored by one logger while all other variables were acquired by a separate logger every 60 s. The protocols associated with the instrumentation, data acquisition, and analysis are discussed in detail. During the first four months, the deployed boulder experienced almost 12 000 AE events, the majority of which occur in the afternoon when temperatures are decreasing. This paper presents preliminary data that illustrates data validity and typical patterns and behaviors observed. This system offers the potential to (1) obtain an unprecedented record of the natural conditions under which rocks fracture and (2) decipher the mechanical processes that lead to rock fracture at a variety of temporal scales under a range of natural conditions.

Automated field detection of rock fracturing, microclimate, and diurnal rock temperature and strain fields

NASA Astrophysics Data System (ADS)

Warren, K.; Eppes, M.-C.; Swami, S.; Garbini, J.; Putkonen, J.

2013-07-01

The rates and processes that lead to non-tectonic rock fracture on the Earth's surface are widely debated but poorly understood. Few, if any, studies have made the direct observations of rock fracturing under natural conditions that are necessary to directly address this problem. An instrumentation design that enables concurrent high spatial and temporal monitoring resolution of (1) diurnal environmental conditions of a natural boulder and its surroundings in addition to (2) the fracturing of that boulder under natural full-sun exposure is described herein. The surface of a fluvially transported granite boulder was instrumented with (1) six acoustic emission (AE) sensors that record micro-crack associated, elastic wave-generated activity within the three-dimensional space of the boulder, (2) eight rectangular rosette foil strain gages to measure surface strain, (3) eight thermocouples to measure surface temperature, and (4) one surface moisture sensor. Additionally, a soil moisture probe and a full weather station that measures ambient temperature, relative humidity, wind speed, wind direction, barometric pressure, insolation, and precipitation were installed adjacent to the test boulder. AE activity was continuously monitored by one logger while all other variables were acquired by a separate logger every 60 s. The protocols associated with the instrumentation, data acquisition, and analyses are discussed in detail. During the first four months, the deployed boulder experienced almost 12 000 AE events, the majority of which occur in the afternoon when temperatures are decreasing. This paper presents preliminary data that illustrates data validity and typical patterns and behaviors observed. This system offers the potential to (1) obtain an unprecedented record of the natural conditions under which rocks fracture and (2) decipher the mechanical processes that lead to rock fracture at a variety of temporal scales under a range of natural conditions.

Preventing falls in assisted living: Results of a quality improvement pilot study.

PubMed

Zimmerman, Sheryl; Greene, Angela; Sloane, Philip D; Mitchell, Madeline; Giuliani, Carol; Nyrop, Kirsten; Walsh, Edith

Residents of assisted living (AL) communities are at high risk for falls, which result in negative outcomes and high health care costs. Adapting effective falls prevention programs for AL quality improvement (QI) has the potential to reduce falls, improve resident quality of life, and reduce costs. This project tested the feasibility and outcomes of an evidence-based multi-component QI program, the Assisted Living Falls Prevention and Monitoring Program (AL-FPMP). Resident posture and gait improved, likely due to exercise and/or physical therapy. Effective falls prevention QI programs can be implemented in AL, and are advised to (1) establish and maintain a falls team to create a culture focused on the reduction of falls risk; (2) teach staff to assess residents using the Morse Falls Scale to increase their awareness of residents' falls risk and improvement; and (3) modify existing exercise programs to address balance and lower body strength. Copyright © 2016 Elsevier Inc. All rights reserved.

Rare Earth Element and Trace Element Data Associated with Hydrothermal Spring Reservoir Rock, Idaho

DOE Data Explorer

Quillinan, Scott; Bagdonas, Davin

2017-06-22

These data represent rock samples collected in Idaho that correspond with naturally occurring hydrothermal samples that were collected and analyzed by INL (Idaho Falls, ID). Representative samples of type rocks were selected to best represent the various regions of Idaho in which naturally occurring hydrothermal waters occur. This includes the Snake River Plain (SRP), Basin and Range type structures east of the SRP, and large scale/deep seated orogenic uplift of the Sawtooth Mountains, ID. Analysis includes ICP-OES and ICP-MS methods for Major, Trace, and REE concentrations.

Real-time oil-saturation monitoring in rock cores with low-field NMR.

PubMed

Mitchell, J; Howe, A M; Clarke, A

2015-07-01

Nuclear magnetic resonance (NMR) provides a powerful suite of tools for studying oil in reservoir core plugs at the laboratory scale. Low-field magnets are preferred for well-log calibration and to minimize magnetic-susceptibility-induced internal gradients in the porous medium. We demonstrate that careful data processing, combined with prior knowledge of the sample properties, enables real-time acquisition and interpretation of saturation state (relative amount of oil and water in the pores of a rock). Robust discrimination of oil and brine is achieved with diffusion weighting. We use this real-time analysis to monitor the forced displacement of oil from porous materials (sintered glass beads and sandstones) and to generate capillary desaturation curves. The real-time output enables in situ modification of the flood protocol and accurate control of the saturation state prior to the acquisition of standard NMR core analysis data, such as diffusion-relaxation correlations. Although applications to oil recovery and core analysis are demonstrated, the implementation highlights the general practicality of low-field NMR as an inline sensor for real-time industrial process control. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultrasonic survey and monitoring of the excavation damaged zone in callovo-oxfordian argillaceous rock

NASA Astrophysics Data System (ADS)

Balland, C.; Morel, J.

2010-12-01

The mining of galleries in geological claystones formation induces a stress redistribution that can cause a microfissuration of the rock around the works which, by coalescence, may generate macro field fractures. In this area called EDZ (Excavation Damaged Zone), permeability is expected to increase drastically. Those induced cracking along with increased permeability, shall be taken into account in safety assessment of deep geological disposal. Ultrasonic survey and monitoring experiments have been performed in the Underground Research Laboratory of Meuse/Haute-Marne to contribute to the understanding of the extension and evolution of this damage. Ultrasonic devices have been deployed around shaft, gallery, slot and borehole to characterize the initiation, the extension and the level of the EDZ, P-wave velocity being very sensitive to the mechanical rock perturbations. The analysis of spatial and temporal velocity field changes gave reliable information on the cracks characteristics of the especially about their opening or their preferential orientation. The results provided by an ultrasonic device around shaft mine by test highlighted the initialization and extension of the damage as the shaft front proceeded. They also showed a polarisation of the velocity field and an oscillation of the transversal isotropy with a preferential orientation of the stress release and the microcracking. Otherwise, with a new automatic and ultrasonic probe, we have found around a borehole that the damage zone extends up to 0.175 diameter of depth with an anisotropic damage pattern oriented according to the regional stress field (Figure 1). Nevertheless, the evolution of this damaged zone is still not well known at longer term, particularly under the influence of parameters such as the reconfining rock in contact with a rigid concrete surface. Is it possible that cracks close up significantly toward their seal? Induced mechanical perturbations are in this case much weaker than those

Fall Risk Assessment and Early-Warning for Toddler Behaviors at Home

PubMed Central

Yang, Mau-Tsuen; Chuang, Min-Wen

2013-01-01

Accidental falls are the major cause of serious injuries in toddlers, with most of these falls happening at home. Instead of providing immediate fall detection based on short-term observations, this paper proposes an early-warning childcare system to monitor fall-prone behaviors of toddlers at home. Using 3D human skeleton tracking and floor plane detection based on depth images captured by a Kinect system, eight fall-prone behavioral modules of toddlers are developed and organized according to four essential criteria: posture, motion, balance, and altitude. The final fall risk assessment is generated by a multi-modal fusion using either a weighted mean thresholding or a support vector machine (SVM) classification. Optimizations are performed to determine local parameter in each module and global parameters of the multi-modal fusion. Experimental results show that the proposed system can assess fall risks and trigger alarms with an accuracy rate of 92% at a speed of 20 frames per second. PMID:24335727

Fall risk assessment and early-warning for toddler behaviors at home.

PubMed

Yang, Mau-Tsuen; Chuang, Min-Wen

2013-12-10

Accidental falls are the major cause of serious injuries in toddlers, with most of these falls happening at home. Instead of providing immediate fall detection based on short-term observations, this paper proposes an early-warning childcare system to monitor fall-prone behaviors of toddlers at home. Using 3D human skeleton tracking and floor plane detection based on depth images captured by a Kinect system, eight fall-prone behavioral modules of toddlers are developed and organized according to four essential criteria: posture, motion, balance, and altitude. The final fall risk assessment is generated by a multi-modal fusion using either a weighted mean thresholding or a support vector machine (SVM) classification. Optimizations are performed to determine local parameter in each module and global parameters of the multi-modal fusion. Experimental results show that the proposed system can assess fall risks and trigger alarms with an accuracy rate of 92% at a speed of 20 frames per second.

Interaction of thermal and mechanical processes in steep permafrost rock walls: A conceptual approach

NASA Astrophysics Data System (ADS)

Draebing, D.; Krautblatter, M.; Dikau, R.

2014-12-01

Degradation of permafrost rock wall decreases stability and can initiate rock slope instability of all magnitudes. Rock instability is controlled by the balance of shear forces and shear resistances. The sensitivity of slope stability to warming results from a complex interplay of shear forces and resistances. Conductive, convective and advective heat transport processes act to warm, degrade and thaw permafrost in rock walls. On a seasonal scale, snow cover changes are a poorly understood key control of the timing and extent of thawing and permafrost degradation. We identified two potential critical time windows where shear forces might exceed shear resistances of the rock. In early summer combined hydrostatic and cryostatic pressure can cause a peak in shear force exceeding high frozen shear resistance and in autumn fast increasing shear forces can exceed slower increasing shear resistance. On a multiannual system scale, shear resistances change from predominantly rock-mechanically to ice-mechanically controlled. Progressive rock bridge failure results in an increase of sensitivity to warming. Climate change alters snow cover and duration and, hereby, thermal and mechanical processes in the rock wall. Amplified thawing of permafrost will result in higher rock slope instability and rock fall activity. We present a holistic conceptual approach connecting thermal and mechanical processes, validate parts of the model with geophysical and kinematic data and develop future scenarios to enhance understanding on system scale.

Comparison and characterization of Android-based fall detection systems.

PubMed

Luque, Rafael; Casilari, Eduardo; Morón, María-José; Redondo, Gema

2014-10-08

Falls are a foremost source of injuries and hospitalization for seniors. The adoption of automatic fall detection mechanisms can noticeably reduce the response time of the medical staff or caregivers when a fall takes place. Smartphones are being increasingly proposed as wearable, cost-effective and not-intrusive systems for fall detection. The exploitation of smartphones' potential (and in particular, the Android Operating System) can benefit from the wide implantation, the growing computational capabilities and the diversity of communication interfaces and embedded sensors of these personal devices. After revising the state-of-the-art on this matter, this study develops an experimental testbed to assess the performance of different fall detection algorithms that ground their decisions on the analysis of the inertial data registered by the accelerometer of the smartphone. Results obtained in a real testbed with diverse individuals indicate that the accuracy of the accelerometry-based techniques to identify the falls depends strongly on the fall pattern. The performed tests also show the difficulty to set detection acceleration thresholds that allow achieving a good trade-off between false negatives (falls that remain unnoticed) and false positives (conventional movements that are erroneously classified as falls). In any case, the study of the evolution of the battery drain reveals that the extra power consumption introduced by the Android monitoring applications cannot be neglected when evaluating the autonomy and even the viability of fall detection systems.

Comparison and Characterization of Android-Based Fall Detection Systems

PubMed Central

Luque, Rafael; Casilari, Eduardo; Morón, María-José; Redondo, Gema

2014-01-01

Falls are a foremost source of injuries and hospitalization for seniors. The adoption of automatic fall detection mechanisms can noticeably reduce the response time of the medical staff or caregivers when a fall takes place. Smartphones are being increasingly proposed as wearable, cost-effective and not-intrusive systems for fall detection. The exploitation of smartphones' potential (and in particular, the Android Operating System) can benefit from the wide implantation, the growing computational capabilities and the diversity of communication interfaces and embedded sensors of these personal devices. After revising the state-of-the-art on this matter, this study develops an experimental testbed to assess the performance of different fall detection algorithms that ground their decisions on the analysis of the inertial data registered by the accelerometer of the smartphone. Results obtained in a real testbed with diverse individuals indicate that the accuracy of the accelerometry-based techniques to identify the falls depends strongly on the fall pattern. The performed tests also show the difficulty to set detection acceleration thresholds that allow achieving a good trade-off between false negatives (falls that remain unnoticed) and false positives (conventional movements that are erroneously classified as falls). In any case, the study of the evolution of the battery drain reveals that the extra power consumption introduced by the Android monitoring applications cannot be neglected when evaluating the autonomy and even the viability of fall detection systems. PMID:25299953

Women's perspectives on falls and fall prevention during pregnancy.

PubMed

Brewin, Dorothy; Naninni, Angela

2014-01-01

Falls are the leading cause of unintentional injury in women. During pregnancy, even a minor fall can result in adverse consequences. Evidence to inform effective and developmentally appropriate pregnancy fall prevention programs is lacking. Early research on pregnancy fall prevention suggests that exercise may reduce falls. However, acceptability and effectiveness of pregnancy fall prevention programs are untested. To better understand postpartum women's perspective and preferences on fall prevention strategies during pregnancy to formulate an intervention. Focus groups and individual interviews were conducted with 31 postpartum women using descriptive qualitative methodology. Discussion of falls during pregnancy and fall prevention strategies was guided by a focus group protocol and enhanced by 1- to 3-minute videos on proposed interventions. Focus groups were audio recorded, transcribed, and analyzed using NVivo 10 software. Emerging themes were environmental circumstances and physical changes of pregnancy leading to a fall, prevention strategies, barriers, safety concerns, and marketing a fall prevention program. Wet surfaces and inappropriate footwear commonly contributed to falls. Women preferred direct provider counseling and programs including yoga and Pilates. Fall prevention strategies tailored to pregnant women are needed. Perspectives of postpartum women support fall prevention through provider counseling and individual or supervised exercise programs.

Automatic fall detection using wearable biomedical signal measurement terminal.

PubMed

Nguyen, Thuy-Trang; Cho, Myeong-Chan; Lee, Tae-Soo

2009-01-01

In our study, we developed a mobile waist-mounted device which can monitor the subject's acceleration signal and detect the fall events in real-time with high accuracy and automatically send an emergency message to a remote server via CDMA module. When fall event happens, the system also generates an alarm sound at 50Hz to alarm other people until a subject can sit up or stand up. A Kionix KXM52-1050 tri-axial accelerometer and a Bellwave BSM856 CDMA standalone modem were used to detect and manage fall events. We used not only a simple threshold algorithm but also some supporting methods to increase an accuracy of our system (nearly 100% in laboratory environment). Timely fall detection can prevent regrettable death due to long-lie effect; therefore increase the independence of elderly people in an unsupervised living environment.

Boring and Sealing Rock with Directed Energy Millimeter-Waves

NASA Astrophysics Data System (ADS)

Woskov, P.; Einstein, H. H.; Oglesby, K.

2015-12-01

Millimeter-wave directed energy is being investigated to penetrate into deep crystalline basement rock formations to lower well costs and to melt rocks, metals, and other additives to seal wells for applications that include nuclear waste storage and geothermal energy. Laboratory tests have established that intense millimeter-wave (MMW) beams > 1 kW/cm2 can melt and/ or vaporize hard crystalline rocks. In principle this will make it possible to create open boreholes and a method to seal them with a glass/ceramic liner and plug formed from the original rock or with other materials. A 10 kW, 28 GHz commercial (CPI) gyrotron system with a launched beam diameter of about 32 mm was used to heat basalt, granite, limestone, and sandstone specimens to temperatures over 2500 °C to create melts and holes. A calibrated 137 GHz radiometer view, collinear with the heating beam, monitored real time peak rock temperature. A water load surrounding the rock test specimen primarily monitored unabsorbed power at 28 GHz. Power balance analysis of the laboratory observations shows that the temperature rise is limited by radiative heat loss, which would be expected to be trapped in a borehole. The analysis also indicates that the emissivity (absorption efficiency) in the radiated infrared range is lower than the emissivity at 28 GHz, giving the MMW frequency range an important advantage for rock melting. Strength tests on one granite type indicated that heating the rock initially weakens it, but with exposure to higher temperatures the resolidified black glassy product regains strength. Basalt was the easiest to melt and penetrate, if a melt leak path was provided, because of its low viscosity. Full beam holes up to about 50 mm diameter (diffraction increased beam size) were achieved through 30 mm thick basalt and granite specimens. Laboratory experiments to form a seal in an existing hole have also been carried out by melting rock and a simulated steel casing.

Monitoring of debris flows and landslides by wired and wireless systems. Experiences from the Catalan Pyrenees.

NASA Astrophysics Data System (ADS)

Hürlimann, Marcel; Abancó, Clàudia; Moya, José; Vilajosana, Ignasi; Llosa, Jordi

2013-04-01

Sophisticated monitoring of landslides for research purpose has started in the 1990thies in the Catalan Pyrenees. Since then several types of mass movements (large landslides, debris flows, shallow landslides and rock falls) and multiples techniques have been applied. In this contribution, special attention will be given to the debris-flow monitoring system installed since summer 2009 in the Rebaixader catchment, Central Pyrenees. The monitoring system has continuously been improved during the last years and nowadays includes devices studying the three major aspects: 1) initiation, 2) flow dynamics, and 3) accumulation. While some parts of the monitoring network include a traditional wired system, the newer parts were installed using low-power wireless devices. Two major aspects will be discussed. First, results of the Rebaixader monitoring site will be presented. Second, experience regarding the monitoring will be evaluated focussing on technical aspects and the comparison between wired and wireless techniques. In the Rebaixader catchment, 6 debris flows and 11 debris floods were observed between August 2009 and October 2012. Surprisingly, also 4 major rock falls were recorded. The rainfall analysis shows that the debris flows were triggered by short, high-intensity rainstorms with a preliminary threshold of about 15 mm during 1 hour. In addition, there was observed a positive trend between event volume and rainfall amount or intensity. The analysis of the ground vibration signals shows significant differences between the time series recorded at the different geophones. These differences are associated with the geophone location in the channel (distance and material), the mounting or the data acquisition system. For instance, the most downstream geophone, installed in bedrock, shows the clearest debris-flows vibration time series, while the uppermost is the most reliable regarding the detection of rockfalls. An evaluation of wired versus wireless monitoring

Rocking and rolling: A can that appears to rock might actually roll

NASA Astrophysics Data System (ADS)

Srinivasan, Manoj; Ruina, Andy

2008-12-01

A beer bottle or soda can on a table, when slightly tipped and released, falls to an upright position and then rocks up to a somewhat opposite tilt. Superficially this rocking motion involves a collision when the flat circular base of the container slaps the table before rocking up to the opposite tilt. A keen eye notices that the after-slap rising tilt is not generally just diametrically opposite the initial tilt but is veered to one side or the other. Cushman and Duistermaat [Regular Chaotic Dyn. 11, 31 (2006)] recently noticed such veering when a flat disk with rolling boundary conditions is dropped nearly flat. Here, we generalize these rolling disk results to arbitrary axi-symmetric bodies and to frictionless sliding. More specifically, we study motions that almost but do not quite involve a face-down collision of the round container’s bottom with the tabletop. These motions involve a sudden rapid motion of the contact point around the circular base. Surprisingly, similar to the rolling disk, the net angle of motion of this contact point is nearly independent of initial conditions. This angle of turn depends simply on the geometry and mass distribution but not on the moment of inertia about the symmetry axis. We derive simple asymptotic formulas for this “angle of turn” of the contact point and check the result with numerics and with simple experiments. For tall containers (height much bigger than radius) the angle of turn is just over π and the sudden rolling motion superficially appears as a nearly symmetric collision leading to leaning on an almost diametrically opposite point on the bottom rim.

Falls and fall-related injuries in older dialysis patients.

PubMed

Cook, Wendy L; Tomlinson, George; Donaldson, Meghan; Markowitz, Samuel N; Naglie, Gary; Sobolev, Boris; Jassal, Sarbjit V

2006-11-01

Dialysis patients are increasingly older and more disabled. In community-dwelling seniors without kidney disease, falls commonly predict hospitalization, the onset of frailty, and the need for institutional care. Effective fall prevention strategies are available. On the basis of retrospective data, it was hypothesized that the fall rates of older (> or =65 yr) chronic outpatient hemodialysis (HD) patients would be higher than published rates for community-dwelling seniors (0.6 to 0.8 falls/patient-year). It also was hypothesized that risk factors for falls in dialysis outpatients would include polypharmacy, dialysis-related hypotension, cognitive impairment, and decreased functional status. Using a prospective cohort study design, HD patients who were > or =65 yr of age at a large academic dialysis unit were recruited. All study participants underwent baseline screening for fall risk factors. Patients were followed prospectively for a minimum of 1 yr. Falls were identified through biweekly patient interviews in the HD unit. A total of 162 patients (mean age 74.7 yr) were recruited; 57% were male. A total of 305 falls occurred in 76 (47%) patients over 190.5 person-years of follow-up (fall-incidence 1.60 falls/person-year). Injuries occurred in 19% of falls; 41 patients had multiple falls. Associated risk factors included age, comorbidity, mean predialysis systolic BP, and a history of falls. In the HD population, the fall risk is higher than in the general community, and fall-related morbidity is high. Better identification of HD patients who are at risk for falls and targeted fall intervention strategies are required.

Monitoring of soil and air-rock temperatures in the Western Massif of the Picos de Europa (Spain)

NASA Astrophysics Data System (ADS)

Ruiz-Fernández, Jesús; Vieira, Gonçalo; García, Cristina

2013-04-01

In this paper we study the ground thermal regime and air-rock interface in the Western Massif of the Picos de Europa (Cantabrian Range, Spain). This calcareous massif is highly affected by karstification processes. Quaternary glaciers, fluvio-torrential processes and present-day periglacial processes also contribute to explain the landforms present in this massif. Up to 9 dataloggers were installed during 6 years in different sites in terms of altitude, orientation, slope and geomorpolohical setting recording temperatures every two hours. The number of freeze-thaw cycles in the soil(between 0 and 16) was controlled by the depth of the snow cover. The temperatures in the interface rock-air showed between 30-60 cycles, reaching 119 and 130 during the year 2007-2008. Extreme minimum temperatures in the soil oscillate between 0.3 and -6.3, while in the rocky walls the loggers recorded temperatures between -7.3 and -14.3°C. Monitoring of soil temperatures around the ice patch - the only one in the massif today - resulted in slightly negative mean annual temperatures. These conditions may reveal the existence of sporadic permafrost on debris that cover the ice patch. Both the buried ice and the permafrost are in disequilibrium with the current environmental conditions of the massif.

Where attention falls: Increased risk of falls from the converging impact of cortical cholinergic and midbrain dopamine loss on striatal function

PubMed Central

Sarter, Martin; Albin, Roger L.; Kucinski, Aaron; Lustig, Cindy

2015-01-01

Falls are a major source of hospitalization, long-term institutionalization, and death in older adults and patients with Parkinson’s disease (PD). Limited attentional resources are a major risk factor for falls. In this review, we specify cognitive–behavioral mechanisms that produce falls and map these mechanisms onto a model of multi-system degeneration. Results from PET studies in PD fallers and findings from a recently developed animal model support the hypothesis that falls result from interactions between loss of basal forebrain cholinergic projections to the cortex and striatal dopamine loss. Striatal dopamine loss produces inefficient, low-vigor gait, posture control, and movement. Cortical cholinergic deafferentation impairs a wide range of attentional processes, including monitoring of gait, posture and complex movements. Cholinergic cell loss reveals the full impact of striatal dopamine loss on motor performance, reflecting loss of compensatory attentional supervision of movement. Dysregulation of dorsomedial striatal circuitry is an essential, albeit not exclusive, mediator of falls in this dual-system model. Because cholinergic neuromodulatory activity influences cortical circuitry primarily via stimulation of α4β2* nicotinic acetylcholine receptors, and because agonists at these receptors are known to benefit attentional processes in animals and humans, treating PD fallers with such agonists, as an adjunct to dopaminergic treatment, is predicted to reduce falls. Falls are an informative behavioral endpoint to study attentional–motor integration by striatal circuitry. PMID:24805070

Reduction in Fall Rate in Dementia Managed Care Through Video Incident Review: Pilot Study.

PubMed

Bayen, Eleonore; Jacquemot, Julien; Netscher, George; Agrawal, Pulkit; Tabb Noyce, Lynn; Bayen, Alexandre

2017-10-17

Falls of individuals with dementia are frequent, dangerous, and costly. Early detection and access to the history of a fall is crucial for efficient care and secondary prevention in cognitively impaired individuals. However, most falls remain unwitnessed events. Furthermore, understanding why and how a fall occurred is a challenge. Video capture and secure transmission of real-world falls thus stands as a promising assistive tool. The objective of this study was to analyze how continuous video monitoring and review of falls of individuals with dementia can support better quality of care. A pilot observational study (July-September 2016) was carried out in a Californian memory care facility. Falls were video-captured (24×7), thanks to 43 wall-mounted cameras (deployed in all common areas and in 10 out of 40 private bedrooms of consenting residents and families). Video review was provided to facility staff, thanks to a customized mobile device app. The outcome measures were the count of residents' falls happening in the video-covered areas, the acceptability of video recording, the analysis of video review, and video replay possibilities for care practice. Over 3 months, 16 falls were video-captured. A drop in fall rate was observed in the last month of the study. Acceptability was good. Video review enabled screening for the severity of falls and fall-related injuries. Video replay enabled identifying cognitive-behavioral deficiencies and environmental circumstances contributing to the fall. This allowed for secondary prevention in high-risk multi-faller individuals and for updated facility care policies regarding a safer living environment for all residents. Video monitoring offers high potential to support conventional care in memory care facilities. ©Eleonore Bayen, Julien Jacquemot, George Netscher, Pulkit Agrawal, Lynn Tabb Noyce, Alexandre Bayen. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 17.10.2017.

Reduction in Fall Rate in Dementia Managed Care Through Video Incident Review: Pilot Study

PubMed Central

Netscher, George; Agrawal, Pulkit; Tabb Noyce, Lynn; Bayen, Alexandre

2017-01-01

Background Falls of individuals with dementia are frequent, dangerous, and costly. Early detection and access to the history of a fall is crucial for efficient care and secondary prevention in cognitively impaired individuals. However, most falls remain unwitnessed events. Furthermore, understanding why and how a fall occurred is a challenge. Video capture and secure transmission of real-world falls thus stands as a promising assistive tool. Objective The objective of this study was to analyze how continuous video monitoring and review of falls of individuals with dementia can support better quality of care. Methods A pilot observational study (July-September 2016) was carried out in a Californian memory care facility. Falls were video-captured (24×7), thanks to 43 wall-mounted cameras (deployed in all common areas and in 10 out of 40 private bedrooms of consenting residents and families). Video review was provided to facility staff, thanks to a customized mobile device app. The outcome measures were the count of residents’ falls happening in the video-covered areas, the acceptability of video recording, the analysis of video review, and video replay possibilities for care practice. Results Over 3 months, 16 falls were video-captured. A drop in fall rate was observed in the last month of the study. Acceptability was good. Video review enabled screening for the severity of falls and fall-related injuries. Video replay enabled identifying cognitive-behavioral deficiencies and environmental circumstances contributing to the fall. This allowed for secondary prevention in high-risk multi-faller individuals and for updated facility care policies regarding a safer living environment for all residents. Conclusions Video monitoring offers high potential to support conventional care in memory care facilities. PMID:29042342

The influence of normal fault on initial state of stress in rock mass

NASA Astrophysics Data System (ADS)

Tajduś, Antoni; Cała, Marek; Tajduś, Krzysztof

2016-03-01

Determination of original state of stress in rock mass is a very difficult task for rock mechanics. Yet, original state of stress in rock mass has fundamental influence on secondary state of stress, which occurs in the vicinity of mining headings. This, in turn, is the cause of the occurrence of a number of mining hazards, i.e., seismic events, rock bursts, gas and rock outbursts, falls of roof. From experience, it is known that original state of stress depends a lot on tectonic disturbances, i.e., faults and folds. In the area of faults, a great number of seismic events occur, often of high energies. These seismic events, in many cases, are the cause of rock bursts and damage to the constructions located inside the rock mass and on the surface of the ground. To estimate the influence of fault existence on the disturbance of original state of stress in rock mass, numerical calculations were done by means of Finite Element Method. In the calculations, it was tried to determine the influence of different factors on state of stress, which occurs in the vicinity of a normal fault, i.e., the influence of normal fault inclination, deformability of rock mass, values of friction coefficient on the fault contact. Critical value of friction coefficient was also determined, when mutual dislocation of rock mass part separated by a fault is impossible. The obtained results enabled formulation of a number of conclusions, which are important in the context of seismic events and rock bursts in the area of faults.

Monitoring and Evaluation of Yearling Fall Chinook Salmon (Oncorhynchus tshawytscha) Released from Acclimation Facilities Upstream of Lower Granite Dam; 2003 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rocklage, Stephen J.

The Nez Perce Tribe, in cooperation with the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife, conducted monitoring and evaluation studies on Lyons Ferry Hatchery reared yearling fall Chinook salmon Oncorhynchus tshawytscha that were acclimated and released at three Fall Chinook Acclimation Project (FCAP) sites upstream of Lower Granite Dam in 2003. This was the eighth year of a long-term project to supplement natural spawning populations of Snake River stock fall Chinook salmon upstream of Lower Granite Dam. The 437,633 yearlings released from the Fall Chinook Acclimation Project facilities were short of the 450,000 fish quota.more » We use Passive Integrated Transponder (PIT) tag technology to monitor the primary performance measures of survival to mainstem dams and migration timing. We also monitor size, condition and tag/mark retention at release. We released 7,492 PIT tagged yearlings from Pittsburg Landing, 7,494 from Big Canyon and 2,497 from Captain John Rapids. Fish health sampling indicated that, overall, bacterial kidney disease levels at the acclimation facilities could be considered medium with 37-83% of the fish sampled rating medium to very high. Mean fork lengths (95% confidence interval) of the PIT tagged groups ranged from 153.7 mm (153.2-154.2 mm) at Captain John Rapids to 164.2 mm (163.9-164.5 mm) at Pittsburg Landing. Mean condition factors ranged from 1.06 at Lyons Ferry Hatchery to 1.22 at Captain John Rapids. Estimated survival (95% confidence interval) of PIT tagged yearlings from release to Lower Granite Dam ranged from 83.1% (80.7-85.5%) for Big Canyon to 91.7% (87.7-95.7%) for Captain John Rapids. Estimated survival from release to McNary Dam ranged from 59.9% (54.6-65.2%) for Big Canyon to 69.4% (60.5-78.4%) for Captain John Rapids. Median migration rates to Lower Granite Dam, based on all observations of PIT tagged yearlings from the FCAP facilities, ranged from 5.8 river kilometers per day (rkm/d) for

Elderly users of fall-risk-increasing drug perceptions of fall risk and the relation to their drug use - a qualitative study.

PubMed

Bell, Hege Therese; Steinsbekk, Aslak; Granas, Anne Gerd

2017-09-01

The aim of the study was to explore how home-dwelling elderly who use fall-risk-increasing drugs (FRIDs) perceive their fall risk and how they relate this to their drug use. A qualitative study with 14 home-dwelling elderly FRID users between 65 and 97 years in Central Norway participating in semi-structured individual interviews. The data were analyzed thematically by using systematic text condensation. The main finding was that the informants did not necessarily perceive the use of FRIDs to be a prominent risk factor for falls. Some informants said they did not reflect upon drug use whatsoever and said they fully trusted their physician's choices. When either experiencing dizziness, fall episodes or by reading the patient information leaflet the informants said to either adjust their drug use or to contact their physician. Some felt rejected due to not getting their point across or their wish to alter the drug was not granted by the physician. Elderly FRID users did not necessarily relate their drug use to fall risk or struggled to present their perceived drug-related problems. Physicians need to regularly inform, monitor and assess the drug treatment when treating elderly with FRIDs.

Report A: Fish distribution and population dynamics in Rock Creek, Klickitat County, Washington

USGS Publications Warehouse

Allen, Brady; Munz, Carrie S.; Harvey, Elaine

2013-01-01

The U.S. Geological Survey collaborated with the Yakama Nation starting in fall of 2009 to study the fish populations in Rock Creek, a Washington State tributary of the Columbia River 21 kilometers upstream of John Day Dam. Prior to this study, very little was known about the ESA-listed (threatened) Mid-Columbia River steelhead (Oncorhynchus mykiss) population in this arid watershed with intermittent stream flow. The objectives of the study were to quantify fish habitat, document fish distribution, abundance, and movement, and identify areas of high salmonid productivity. To accomplish these objectives, we electrofished in the spring and fall, documenting the distribution and relative abundance of all fish species to evaluate the influence of biotic factors on salmonid productivity and survival. We surveyed the distribution of perennial pools and established a network of automated temperature recording devices from river kilometer (rkm) 2 to 23 in Rock Creek and rkm 0 to 8 in Squaw Creek, a major tributary entering Rock Creek at rkm 13, to better understand the abiotic factors influencing the salmonid populations. Salmonid abundance estimates were conducted using a mark-recapture method in a systematic subsample of the perennial pools. The proportion and timing of salmonids migrating from these pools were assessed by building, installing, and operating two passive integrated transponder (PIT) tag interrogation systems at rkm 5 and at the confluence with Squaw Creek (rkm 13). From fall 2009 to fall 2012, we PIT-tagged 3,088 O. mykiss and 151 coho salmon (O. kisutch) during electrofishing efforts. In the lowest flow periods of 2010 to 2012, we found that an average of 36% of the surveyed streambed length was dry, and 17% remained as perennial pools. The maximum temperature recorded in those pools was 24.4°C, but most pools had a maximum temperature that was less than 21°C. O. mykiss were present in most pools, and non-native fish species, such as smallmouth bass

Contrasted glass-whole rock compositions and phenocryst re-distribution, IPOD Sites 417 and 418

NASA Astrophysics Data System (ADS)

Staudigel, H.; Bryan, W. B.

1982-01-01

Major element composition ranges of closely associated basalt glass-whole rock pairs from individual small cooling units approach the total known range of basalt glass and whole rock compositions at IPOD sites 417 and 418. The whole rock samples fall into two groups: one is depleted in MgO and distinctly enriched in plagioclase but has lost some olivine and/or pyroxene relative to its corresponding glass; and the other is enriched in MgO and in phenocrysts of olivine and pyroxene as well as plagioclase compared to its corresponding glass. By analogy with observed phenocryst distributions in lava pillows, tubes, and dikes, and with some theoretical studies, we infer that bulk rock compositions are strongly affected by phenocryst redistribution due to gravity settling, flotation, and dynamic sorting after eruption, although specific models are not well constrained by the one-dimensional geometry of drill core. Compositional trends or groupings in whole rock data resulting from such late-stage processes should not be confused with more fundamental compositional effects produced in deep chambers or during partial melting.

Does smart home technology prevent falls in community-dwelling older adults: a literature review.

PubMed

Pietrzak, Eva; Cotea, Cristina; Pullman, Stephen

2014-01-01

Falls in older Australians are an increasingly costly public health issue, driving the development of novel modes of intervention, especially those that rely on computer-driven technologies. The aim of this paper was to gain an understanding of the state of the art of research on smart homes and computer-based monitoring technologies to prevent and detect falls in the community-dwelling elderly. Cochrane, Medline, Embase and Google databases were searched for articles on fall prevention in the elderly using pre-specified search terms. Additional papers were searched for in the reference lists of relevant reviews and by the process of 'snowballing'. Only studies that investigated outcomes related to falling such as fall prevention and detection, change in participants' fear of falling and attitudes towards monitoring technology were included. Nine papers fulfilled the inclusion criteria. The following outcomes were observed: (1) older adults' attitudes towards fall detectors and smart home technology are generally positive; (2) privacy concerns and intrusiveness of technology were perceived as less important to participants than their perception of health needs and (3) unfriendly and age-inappropriate design of the interface may be one of the deciding factors in not using the technology. So far, there is little evidence that using smart home technology may assist in fall prevention or detection, but there are some indications that it may increase older adults' confidence and sense of security, thus possibly enabling aging in place.

Relationship between subjective fall risk assessment and falls and fall-related fractures in frail elderly people

PubMed Central

2011-01-01

Background Objective measurements can be used to identify people with risks of falls, but many frail elderly adults cannot complete physical performance tests. The study examined the relationship between a subjective risk rating of specific tasks (SRRST) to screen for fall risks and falls and fall-related fractures in frail elderly people. Methods The SRRST was investigated in 5,062 individuals aged 65 years or older who were utilized day-care services. The SRRST comprised 7 dichotomous questions to screen for fall risks during movements and behaviours such as walking, transferring, and wandering. The history of falls and fall-related fractures during the previous year was reported by participants or determined from an interview with the participant's family and care staff. Results All SRRST items showed significant differences between the participants with and without falls and fall-related fractures. In multiple logistic regression analysis adjusted for age, sex, diseases, and behavioural variables, the SRRST score was independently associated with history of falls and fractures. Odds ratios for those in the high-risk SRRST group (≥ 5 points) compared with the no risk SRRST group (0 point) were 6.15 (p < 0.01) for a single fall, 15.04 (p < 0.01) for recurrent falls, and 5.05 (p < 0.01) for fall-related fractures. The results remained essentially unchanged in subgroup analysis accounting for locomotion status. Conclusion These results suggest that subjective ratings by care staff can be utilized to determine the risks of falls and fall-related fractures in the frail elderly, however, these preliminary results require confirmation in further prospective research. PMID:21838891

Microseismicity of an Unstable Rock Mass: From Field Monitoring to Laboratory Testing

NASA Astrophysics Data System (ADS)

Colombero, C.; Comina, C.; Vinciguerra, S.; Benson, P. M.

2018-02-01

The field-scale microseismic (MS) activity of an unstable rock mass is known to be an important tool to assess damage and cracking processes eventually leading to macroscopic failures. However, MS-event rates alone may not be enough for a complete understanding of the trigger mechanisms of mechanical instabilities. Acoustic Emission (AE) techniques at the laboratory scale can be used to provide complementary information. In this study, we report a MS/AE comparison to assess the stability of a granitic rock mass in the northwestern Italian Alps (Madonna del Sasso). An attempt to bridge the gap between the two different scales of observation, and the different site and laboratory conditions, is undertaken to gain insights on the rock mass behavior as a function of external governing factors. Time- and frequency-domain parameters of the MS/AE waveforms are compared and discussed with this aim. At the field scale, special attention is devoted to the correlation of the MS-event rate with meteorological parameters (air temperature and rainfalls). At the laboratory scale, AE rates, waveforms, and spectral content, recorded under controlled temperature and fluid conditions, are analyzed in order to better constrain the physical mechanisms responsible for the observed field patterns. The factors potentially governing the mechanical instability at the site were retrieved from the integration of the results. Abrupt thermal variations were identified as the main cause of the site microsesimicity, without highlighting irreversible acceleration in the MS-event rate potentially anticipating the rock mass collapse.

Where attention falls: Increased risk of falls from the converging impact of cortical cholinergic and midbrain dopamine loss on striatal function.

PubMed

Sarter, Martin; Albin, Roger L; Kucinski, Aaron; Lustig, Cindy

2014-07-01

Falls are a major source of hospitalization, long-term institutionalization, and death in older adults and patients with Parkinson's disease (PD). Limited attentional resources are a major risk factor for falls. In this review, we specify cognitive-behavioral mechanisms that produce falls and map these mechanisms onto a model of multi-system degeneration. Results from PET studies in PD fallers and findings from a recently developed animal model support the hypothesis that falls result from interactions between loss of basal forebrain cholinergic projections to the cortex and striatal dopamine loss. Striatal dopamine loss produces inefficient, low-vigor gait, posture control, and movement. Cortical cholinergic deafferentation impairs a wide range of attentional processes, including monitoring of gait, posture and complex movements. Cholinergic cell loss reveals the full impact of striatal dopamine loss on motor performance, reflecting loss of compensatory attentional supervision of movement. Dysregulation of dorsomedial striatal circuitry is an essential, albeit not exclusive, mediator of falls in this dual-system model. Because cholinergic neuromodulatory activity influences cortical circuitry primarily via stimulation of α4β2* nicotinic acetylcholine receptors, and because agonists at these receptors are known to benefit attentional processes in animals and humans, treating PD fallers with such agonists, as an adjunct to dopaminergic treatment, is predicted to reduce falls. Falls are an informative behavioral endpoint to study attentional-motor integration by striatal circuitry. Copyright © 2014 Elsevier Inc. All rights reserved.

Jing and King Receive Mineral and Rock Physics Graduate Research Awards

NASA Astrophysics Data System (ADS)

Anonymous

2012-02-01

Zhicheng Jing and Daniel King have been awarded the 2011 Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origin and physical properties. Jing's thesis is entitled "Equation of state of silicate liquids." King's thesis is entitled "Stress-driven melt segregation and reactive melt infiltration in partially molten rocks deformed in torsion with applications to melt extraction from Earth's mantle." They both were formally presented with the award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif.

Embedded DSP-based telehealth radar system for remote in-door fall detection.

PubMed

Garripoli, Carmine; Mercuri, Marco; Karsmakers, Peter; Jack Soh, Ping; Crupi, Giovanni; Vandenbosch, Guy A E; Pace, Calogero; Leroux, Paul; Schreurs, Dominique

2015-01-01

Telehealth systems and applications are extensively investigated nowadays to enhance the quality-of-care and, in particular, to detect emergency situations and to monitor the well-being of elderly people, allowing them to stay at home independently as long as possible. In this paper, an embedded telehealth system for continuous, automatic, and remote monitoring of real-time fall emergencies is presented and discussed. The system, consisting of a radar sensor and base station, represents a cost-effective and efficient healthcare solution. The implementation of the fall detection data processing technique, based on the least-square support vector machines, through a digital signal processor and the management of the communication between radar sensor and base station are detailed. Experimental tests, for a total of 65 mimicked fall incidents, recorded with 16 human subjects (14 men and two women) that have been monitored for 320 min, have been used to validate the proposed system under real circumstances. The subjects' weight is between 55 and 90 kg with heights between 1.65 and 1.82 m, while their age is between 25 and 39 years. The experimental results have shown a sensitivity to detect the fall events in real time of 100% without reporting false positives. The tests have been performed in an area where the radar's operation was not limited by practical situations, namely, signal power, coverage of the antennas, and presence of obstacles between the subject and the antennas.

Interannual variability of rock glacier surface velocities and its relationship to climatic conditions on a decadal scale: Some insights from the European Alps

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas; Bodin, Xavier; Delaloye, Reynald; Fischer, Andrea; Gärtner-Roer, Isabelle; Hartl, Lea; Kaufmann, Viktor; Krainer, Karl; Lambiel, Christophe; Mair, Volkmar; Marcer, Marco; Morra di Cella, Umberto; Scapozza, Cristian; Schoeneich, Philippe; Staub, Benno

2017-04-01

Active, inactive and relict rock glaciers are widespread periglacial landforms in the European Alps as revealed by several inventories elaborated for Slovenia, Austria, Switzerland, Italy, and France. Rock glaciers indicate present or past permafrost conditions in mountain environments and hence have a high climatic or paleoclimatic relevance. The monitoring of surface velocities at active rock glaciers has a long tradition in the European Alps with first terrestrial photogrammetric surveys in the Swiss and Austrian Alps already in the 1920s. Since the 1990s velocity monitoring activities have been substantially expanded but also institutionalized. Today, several research groups carry out annual or even continuous monitoring of rock glacier creep at more than 30 rock glaciers in Austria, France, Italy, and Switzerland. In many cases such a kinematic monitoring is jointly accomplished with meteorological and ground temperature monitoring in order to better understand the rock glacier-climate relationships and the reaction of rock glacier behavior to climatic changes. In this contribution we present a synthesis of the main results from long-term monitoring of several rock glaciers in the European Alps with at least annually-repeated data. Similarities but also differences of the movement patterns at the different sites are discussed, while the spatio-temporal pattern of the surface displacement is looked at against the climate context. In general, rock glacier surface velocities in the European Alps have been rather low during the 1980s and 1990s and reached a first peak in 2003/04 followed by a drastic drop until c.2007/08. Since then rock glacier surface velocities increased again with new velocity records in 2015/16 superior to the first peak around 2003/04. These creep rate maxima coincide with the warmest permafrost temperatures ever measured in boreholes and are likely a result of the continuously warm conditions at the ground surface over the past seven years.

Mobility, balance and falls in persons with multiple sclerosis.

PubMed

Sosnoff, Jacob J; Socie, Michael J; Boes, Morgan K; Sandroff, Brian M; Pula, John H; Suh, Yoojin; Weikert, Madeline; Balantrapu, Swathi; Morrison, Steven; Motl, Robert W

2011-01-01

There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS (PwMS). This investigation assessed the relation between demographic, clinical, mobility and balance metrics and falls history in persons with multiple sclerosis (MS). 52 ambulatory persons with MS (PwMS) participated in the investigation. All persons provided demographic information including fall history over the last 12 months. Disease status was assessed with Expanded Disability Status Scale (EDSS). Walking speed, coordination, endurance and postural control were quantified with a multidimensional mobility battery. Over 51% of the participants fell in the previous year with 79% of these people being suffering recurrent falls. Overall, fallers were older, had a greater prevalence of assistive devices use, worse disability, decreased walking endurance, and greater postural sway velocity with eyes closed compared to non-fallers. Additionally, fallers had greater impairment in cerebellar, sensory, pyramidal, and bladder/bowel subscales of the EDSS. The current observations suggest that PwMS who are older, more disabled, utilize an assistive device, have decreased walking coordination and endurance and have diminished balance have fallen in the previous year. This suggests that individuals who meet these criteria need to be carefully monitored for future falls. Future research is needed to determine a prospective model of falls specific to PwMS. Additionally, the utility of interventions aimed at reducing falls and fall risk in PwMS needs to be established.

Mobility, Balance and Falls in Persons with Multiple Sclerosis

PubMed Central

Sosnoff, Jacob J.; Socie, Michael J.; Boes, Morgan K.; Sandroff, Brian M.; Pula, John H.; Suh, Yoojin; Weikert, Madeline; Balantrapu, Swathi; Morrison, Steven; Motl, Robert W.

2011-01-01

Background There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS (PwMS). This investigation assessed the relation between demographic, clinical, mobility and balance metrics and falls history in persons with multiple sclerosis (MS). Methods 52 ambulatory persons with MS (PwMS) participated in the investigation. All persons provided demographic information including fall history over the last 12 months. Disease status was assessed with Expanded Disability Status Scale (EDSS). Walking speed, coordination, endurance and postural control were quantified with a multidimensional mobility battery. Results Over 51% of the participants fell in the previous year with 79% of these people being suffering recurrent falls. Overall, fallers were older, had a greater prevalence of assistive devices use, worse disability, decreased walking endurance, and greater postural sway velocity with eyes closed compared to non-fallers. Additionally, fallers had greater impairment in cerebellar, sensory, pyramidal, and bladder/bowel subscales of the EDSS. Conclusions The current observations suggest that PwMS who are older, more disabled, utilize an assistive device, have decreased walking coordination and endurance and have diminished balance have fallen in the previous year. This suggests that individuals who meet these criteria need to be carefully monitored for future falls. Future research is needed to determine a prospective model of falls specific to PwMS. Additionally, the utility of interventions aimed at reducing falls and fall risk in PwMS needs to be established. PMID:22132196

Patient centered fall risk awareness perspectives: clinical correlates and fall risk

PubMed Central

Verghese, Joe

2016-01-01

Background While objective measures to assess risk of falls in older adults have been established; the value of patient self-reports in the context of falls is not known. Objectives To identify clinical correlates of patient centered fall risk awareness, and their validity for predicting falls. Design Prospective cohort study. Setting and Participants 316 non-demented and ambulatory community-dwelling older adults (mean age 78 years, 55% women). Measurements Fall risk awareness was assessed with a two-item questionnaire, which asked participants about overall likelihood and personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Results Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (kappa 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on both fall risk awareness questions. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Conclusion Fall risk awareness is low in older adults. While patient centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies as they may influence participation and behaviors. PMID:27801936

Fall-related activity avoidance in relation to a history of falls or near falls, fear of falling and disease severity in people with Parkinson's disease.

PubMed

Kader, Manzur; Iwarsson, Susanne; Odin, Per; Nilsson, Maria H

2016-06-02

There is limited knowledge concerning fall-related activity avoidance in people with Parkinson's disease (PD); such knowledge would be of importance for the development of more efficient PD-care and rehabilitation. This study aimed to examine how fall-related activity avoidance relates to a history of self-reported falls/near falls and fear of falling (FOF) as well as to disease severity in people with PD. Data were collected from 251 (61 % men) participants with PD; their median (min-max) age and PD duration were 70 (45-93) and 8 (1-43) years, respectively. A self-administered postal survey preceded a home visit which included observations, clinical tests and interview-administered questionnaires. Fall-related activity avoidance was assessed using the modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE) as well as by using a dichotomous (Yes/No) question. Further dichotomous questions concerned: the presence of FOF and the history (past 6 months) of falls or near falls, followed by stating the number of incidents. Disease severity was assessed according to the Hoehn and Yahr (HY) stages. In the total sample (n = 251), 41 % of the participants reported fall-related activity avoidance; the median mSAFFE score was 22. In relation to a history of fall, the proportions of participants (p < 0.001) that reported fall-related activity avoidance were: non-fallers (30 %), single fallers (50 %) and recurrent fallers, i.e. ≥ 2 falls (57 %). Among those that reported near falls (but no falls), 51 % (26 out of 51) reported fall-related activity avoidance. Of those that reported FOF, 70 % reported fall-related activity avoidance. Fall-related activity avoidance ranged from 24 % in the early PD-stage (HY I) to 74 % in the most severe stages (HY IV-V). Results indicate that fall-related activity avoidance may be related to a history of self-reported falls/near falls, FOF and disease severity in people with PD. Importantly, fall

White Rock

NASA Technical Reports Server (NTRS)

2002-01-01

(Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can

Novel Hierarchical Fall Detection Algorithm Using a Multiphase Fall Model.

PubMed

Hsieh, Chia-Yeh; Liu, Kai-Chun; Huang, Chih-Ning; Chu, Woei-Chyn; Chan, Chia-Tai

2017-02-08

Falls are the primary cause of accidents for the elderly in the living environment. Reducing hazards in the living environment and performing exercises for training balance and muscles are the common strategies for fall prevention. However, falls cannot be avoided completely; fall detection provides an alarm that can decrease injuries or death caused by the lack of rescue. The automatic fall detection system has opportunities to provide real-time emergency alarms for improving the safety and quality of home healthcare services. Two common technical challenges are also tackled in order to provide a reliable fall detection algorithm, including variability and ambiguity. We propose a novel hierarchical fall detection algorithm involving threshold-based and knowledge-based approaches to detect a fall event. The threshold-based approach efficiently supports the detection and identification of fall events from continuous sensor data. A multiphase fall model is utilized, including free fall, impact, and rest phases for the knowledge-based approach, which identifies fall events and has the potential to deal with the aforementioned technical challenges of a fall detection system. Seven kinds of falls and seven types of daily activities arranged in an experiment are used to explore the performance of the proposed fall detection algorithm. The overall performances of the sensitivity, specificity, precision, and accuracy using a knowledge-based algorithm are 99.79%, 98.74%, 99.05% and 99.33%, respectively. The results show that the proposed novel hierarchical fall detection algorithm can cope with the variability and ambiguity of the technical challenges and fulfill the reliability, adaptability, and flexibility requirements of an automatic fall detection system with respect to the individual differences.

Novel Hierarchical Fall Detection Algorithm Using a Multiphase Fall Model

PubMed Central

Hsieh, Chia-Yeh; Liu, Kai-Chun; Huang, Chih-Ning; Chu, Woei-Chyn; Chan, Chia-Tai

2017-01-01

Falls are the primary cause of accidents for the elderly in the living environment. Reducing hazards in the living environment and performing exercises for training balance and muscles are the common strategies for fall prevention. However, falls cannot be avoided completely; fall detection provides an alarm that can decrease injuries or death caused by the lack of rescue. The automatic fall detection system has opportunities to provide real-time emergency alarms for improving the safety and quality of home healthcare services. Two common technical challenges are also tackled in order to provide a reliable fall detection algorithm, including variability and ambiguity. We propose a novel hierarchical fall detection algorithm involving threshold-based and knowledge-based approaches to detect a fall event. The threshold-based approach efficiently supports the detection and identification of fall events from continuous sensor data. A multiphase fall model is utilized, including free fall, impact, and rest phases for the knowledge-based approach, which identifies fall events and has the potential to deal with the aforementioned technical challenges of a fall detection system. Seven kinds of falls and seven types of daily activities arranged in an experiment are used to explore the performance of the proposed fall detection algorithm. The overall performances of the sensitivity, specificity, precision, and accuracy using a knowledge-based algorithm are 99.79%, 98.74%, 99.05% and 99.33%, respectively. The results show that the proposed novel hierarchical fall detection algorithm can cope with the variability and ambiguity of the technical challenges and fulfill the reliability, adaptability, and flexibility requirements of an automatic fall detection system with respect to the individual differences. PMID:28208694

Mitigating fall risk: A community fall reduction program.

PubMed

Reinoso, Humberto; McCaffrey, Ruth G; Taylor, David W M

One fourth of all American's over 65 years of age fall each year. Falls are a common and often devastating event that can pose a serious health risk for older adults. Healthcare providers are often unable to spend the time required to assist older adults with fall risk issues. Without a team approach to fall prevention the system remains focused on fragmented levels of health promotion and risk prevention. The specific aim of this project was to engage older adults from the community in a fall risk assessment program, using the Stopping Elderly Accidents, Deaths & Injuries (STEADI) program, and provide feedback on individual participants' risks that participants could share with their primary care physician. Older adults who attended the risk screening were taking medications that are known to increase falls. They mentioned that their health care providers do not screen for falls and appreciated a community based screening. Copyright © 2017 Elsevier Inc. All rights reserved.

Pre-Procedural Patient Education Reduces Fall Risk in an Outpatient Endoscopy Suite.

PubMed

Hilscher, Moira B; Niesen, Cynthia R; Tynsky, Desiree A; Kane, Sunanda V

The purpose of this article was to determine whether scripted pre-procedural fall risk patient education and nurses' intention to assist patients after receiving sedation improves receptiveness of nursing assistance during recovery and decreases fall risk in an outpatient endoscopy suite. We prospectively identified high fall risk patients using the following criteria: (1) use of an assistive device, (2) fallen two or more times within the last year, (3) sustained an injury in a fall within a year, (4) age greater than 85 years, or (5) nursing judgment of high fall risk. Using a scripted dialogue, nurses educated high-risk patients of their fall risk and the nurses' intent to assist them to and in the bathroom. Documentation of patient education, script use, and assistance was monitored. Over 24 weeks, 892 endoscopy patients were identified as high fall risk; 790 (88.5%) accepted post-procedural assistance. Documentation of assistance significantly increased from 33% to 100%. Patients receiving education and postprocedural assistance increased from 27.9% to 100% at week 24. No patient falls occurred 12 months following implementation among patients identified as high fall risk. Scripted pre-procedural fall risk education increases patient awareness and receptiveness to assistance and can lead to decreased fall rates.

Person-Centered Fall Risk Awareness Perspectives: Clinical Correlates and Fall Risk.

PubMed

Verghese, Joe

2016-12-01

To identify clinical correlates of person-centered fall risk awareness and their validity for predicting falls. Prospective cohort study. Community. Ambulatory community-dwelling older adults without dementia (N = 316; mean age 78, 55% female). Fall risk awareness was assessed using a two-item questionnaire that asked participants about overall likelihood of someone in their age group having a fall and their own personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (κ = 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on either fall risk awareness question. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Fall risk awareness is low in older adults. Although person-centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies because they may influence participation and behaviors. © 2016, Copyright the Author Journal compilation © 2016, The American Geriatrics Society.

148. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

148. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER DAM; HEADGATES AT INLET, SOUTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

98. SHOESTRING, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

98. SHOESTRING, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; PROFILE VIEW, SOUTH. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

52. VIEW SHOWING SITE OF ARIZONA FALL POWER PLANT, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

52. VIEW SHOWING SITE OF ARIZONA FALL POWER PLANT, LOOKING EAST. CURRENT LOCATION OF THE REAL-TIME WATER QUALITY MONITORING STATION Photographer: James Eastwood, July 1990 - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

Cold rock coast geomorphology: A quantitative analysis of rock coast processes in Hornsund.

NASA Astrophysics Data System (ADS)

Lim, Michael; Strzelecki, Matt; Kasprzak, Marek; Jaskolski, Marek; Pawlowski, Lukasz; Swirad, Zuzanna; Bell, Heather; Migon, Piotr

2017-04-01

Many arctic coastal systems are experiencing altered thermal and hydrological regimes. Of particular note within the High Arctic is Svalbard, a region undergoing a distinct and sustained rise in mean annual temperatures. Hornsund, at the southern tip of the Svalbard archipelago, is situated at the northern extreme of the North Atlantic current and as such provides a site of unique climate sensitivity with a concentration of geomorphic processes. There is a paucity of studies achieving sufficient resolution to account for geomorphic behaviour and over timescales that allow climatic conditioning to be considered. This research utilises high resolution multiscale surface monitoring and characterisation to quantify and model both contemporary and relic cliff responses in order to revisit one of the first quantitative studies, undertaken almost sixty years ago, on the rates and intensities of rock coast change. The fragmentation and failure in contemporary coastal cliff responses reflects a decrease in the overall rates of change relative to historic rates during a period that has seen the loss of an icefoot that regularly lasted until late summer and a transition to open water coastal dynamics. To investigate the drivers of rock degradation and failure, thermal analyses that characterise both spatial and temporal patterns across and within the rock coast have been used to indicate a potential shift in process activity zones. The significance of localised influences such as storm influences, iceberg influxes and topographic shading highlights some considerations for the development of broader scale models of rock coast evolution.

147. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

147. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, IDAHO; VIEW OF MAIN HEADGATES, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Hyponatremia as a fall predictor in a geriatric trauma population.

PubMed

Rittenhouse, Katelyn J; To, Tuc; Rogers, Amelia; Wu, Daniel; Horst, Michael; Edavettal, Mathew; Miller, Jo Ann; Rogers, Frederick B

2015-01-01

Approximately one in three older adults fall each year, resulting in a significant proportion of geriatric traumatic injuries. In a hospital with a focus on geriatric fall prevention, we sought to characterize this population to develop targeted interventions. As mild hyponatremia, defined as a serum sodium <135meq/L, has been reported to be associated with falls, unsteadiness and attention deficits, we hypothesized that hyponatremia is associated with falls in our geriatric trauma population. Gender, age, pre-existing conditions (cardiac disease, diabetes, hematologic disorder, liver disease, malignancy, musculoskeletal disorder, neurological disorder, obesity, psychiatric disorder, pulmonary disease, renal disease, thyroid disease), mechanism of injury and admitting serum sodium level were queried for all geriatric trauma admissions from 2008 to 2011. Mechanism of injury was coded as falls admissions and non-falls admissions. Admitting serum sodium levels were coded as hyponatremic (<135mmol/L) and not hyponatremic (≥135mmol/L). Of the 2370 geriatric trauma admissions during the study period, there were 1841 (77.7%) falls admissions and 293 (12.4%) patients who were hyponatremic. Gender, age, neurological disorder, hematologic disorder, and hyponatremia were found to be significant predictors of falls in both univariate and multivariable analyses. Hyponatremic patients are significantly more likely to be admitted for a fall than non-hyponatremic patients, when adjusting for age, neurological disorder, and hematologic disorder. Consequently, hyponatremia identification and management should be an integral part of any geriatric trauma fall prevention programme. Additionally, if hyponatremia is found during a geriatric fall workup, it should be corrected prior to discharge and closely monitored by a primary care physician to prevent recurrent episodes of falls. Copyright © 2014 Elsevier Ltd. All rights reserved.

97. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

97. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; OVERALL WEST VIEW FROM CANAL SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

149. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

149. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER DAM; CLOSE-UP OF MAIN CANAL GATES, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Fall risk: the clinical relevance of falls and how to integrate fall risk with fracture risk.

PubMed

Peeters, G; van Schoor, Natasja M; Lips, Paul

2009-12-01

In old age, 5-10% percent of all falls result in a fracture, and up to 90% of all fractures result from a fall. This article describes the link between fall risk and fracture risk in community-dwelling older persons. Which factors attribute to both the fall risk and the fracture risk? Which falls result in a fracture? Which tools are available to predict falls and fractures? Directions for the use of prediction tools in clinical practice are given. Challenges for future research include further validation of existing prediction tools and evaluation of the cost-effectiveness of treatment after screening.

Falls and Fear of Falling After Stroke: A Case-Control Study.

PubMed

Goh, Hui-Ting; Nadarajah, Mohanasuntharaam; Hamzah, Norhamizan Binti; Varadan, Parimalaganthi; Tan, Maw Pin

2016-12-01

Falls are common after stroke, with potentially serious consequences. Few investigations have included age-matched control participants to directly compare fall characteristics between older adults with and without stroke. Further, fear of falling, a significant psychological consequence of falls, has only been examined to a limited degree as a risk factor for future falls in a stroke population. To compare the fall history between older adults with and without a previous stroke and to identify the determinants of falls and fear of falling in older stroke survivors. Case-control observational study. Primary teaching hospital. Seventy-five patients with stroke (mean age ± standard deviation, 66 ± 7 years) and 50 age-matched control participants with no previous stroke were tested. Fall history, fear of falling, and physical, cognitive, and psychological function were assessed. A χ 2 test was performed to compare characteristics between groups, and logistic regression was performed to determine the risk factors for falls and fear of falling. Fall events in the past 12 months, Fall Efficacy Scale-International, Berg Balance Scale, Functional Ambulation Category, Fatigue Severity Scale, Montreal Cognitive Assessment, and Patient Healthy Questionnaire-9 were measured for all participants. Fugl-Meyer Motor Assessment was used to quantify severity of stroke motor impairments. Twenty-three patients and 13 control participants reported at least one fall in the past 12 months (P = .58). Nine participants with stroke had recurrent falls (≥2 falls) compared with none of the control participants (P < .01). Participants with stroke reported greater concern for falling than did nonstroke control participants (P < .01). Female gender was associated with falls in the nonstroke group, whereas falls in the stroke group were not significantly associated with any measured outcomes. Fear of falling in the stroke group was associated with functional ambulation level and balance

141. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

141. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, IDAHO; CLOSE-UP OF MAIN HEADGATES, RADIAL GATES INSIDE, SOUTHEAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Evaluation of stress and saturation effects on seismic velocity and electrical resistivity - laboratory testing of rock samples

NASA Astrophysics Data System (ADS)

Vilhelm, Jan; Jirků, Jaroslav; Slavík, Lubomír; Bárta, Jaroslav

2016-04-01

Repository, located in a deep geological formation, is today considered the most suitable solution for disposal of spent nuclear fuel and high-level waste. The geological formations, in combination with an engineered barrier system, should ensure isolation of the waste from the environment for thousands of years. For long-term monitoring of such underground excavations special monitoring systems are developed. In our research we developed and tested monitoring system based on repeated ultrasonic time of flight measurement and electrical resistivity tomography (ERT). As a test site Bedřichov gallery in the northern Bohemia was selected. This underground gallery in granitic rock was excavated using Tunnel Boring Machine (TBM). The seismic high-frequency measurements are performed by pulse-transmission technique directly on the rock wall using one seismic source and three receivers in the distances of 1, 2 and 3 m. The ERT measurement is performed also on the rock wall using 48 electrodes. The spacing between electrodes is 20 centimeters. An analysis of relation of seismic velocity and electrical resistivity on water saturation and stress state of the granitic rock is necessary for the interpretation of both seismic monitoring and ERT. Laboratory seismic and resistivity measurements were performed. One series of experiments was based on uniaxial loading of dry and saturated granitic samples. The relation between stress state and ultrasonic wave velocities was tested separately for dry and saturated rock samples. Other experiments were focused on the relation between electrical resistivity of the rock sample and its saturation level. Rock samples with different porosities were tested. Acknowledgments: This work was partially supported by the Technology Agency of the Czech Republic, project No. TA 0302408

Falling and fall risk in adult patients with severe haemophilia.

PubMed

Rehm, Hanna; Schmolders, Jan; Koob, Sebastian; Bornemann, Rahel; Goldmann, Georg; Oldenburg, Johannes; Pennekamp, Peter; Strauss, Andreas C

2017-05-10

The objective of this study was to define fall rates and to identify possible fall risk factors in adult patients with severe haemophilia. 147 patients with severe haemophilia A and B were evaluated using a standardized test battery consisting of demographic, medical and clinical variables and fall evaluation. 41 (27.9 %) patients reported a fall in the past 12 months, 22 (53.7 %) of them more than once. Young age, subjective gait insecurity and a higher number of artificial joints seem to be risk factors for falling. Falls seem to be a common phenomenon in patients with severe haemophilia. Fall risk screening and fall prevention should be implemented into daily practice.

99. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

99. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; CLOSE-UP OF OUTLET SIDE OF GATES, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Accurate Fall Detection in a Top View Privacy Preserving Configuration.

PubMed

Ricciuti, Manola; Spinsante, Susanna; Gambi, Ennio

2018-05-29

Fall detection is one of the most investigated themes in the research on assistive solutions for aged people. In particular, a false-alarm-free discrimination between falls and non-falls is indispensable, especially to assist elderly people living alone. Current technological solutions designed to monitor several types of activities in indoor environments can guarantee absolute privacy to the people that decide to rely on them. Devices integrating RGB and depth cameras, such as the Microsoft Kinect, can ensure privacy and anonymity, since the depth information is considered to extract only meaningful information from video streams. In this paper, we propose an accurate fall detection method investigating the depth frames of the human body using a single device in a top-view configuration, with the subjects located under the device inside a room. Features extracted from depth frames train a classifier based on a binary support vector machine learning algorithm. The dataset includes 32 falls and 8 activities considered for comparison, for a total of 800 sequences performed by 20 adults. The system showed an accuracy of 98.6% and only one false positive.

Wireless Falling Detection System Based on Community.

PubMed

Xia, Yun; Wu, Yanqi; Zhang, Bobo; Li, Zhiyang; He, Nongyue; Li, Song

2015-06-01

The elderly are more likely to suffer the aches or pains from the accidental falls, and both the physiology and psychology of patients would subject to a long-term disturbance, especially when the emergency treatment was not given timely and properly. Although many methods and devices have been developed creatively and shown their efficiency in experiments, few of them are suitable for commercial applications routinely. Here, we design a wearable falling detector as a mobile terminal, and utilize the wireless technology to transfer and monitor the activity data of the host in a relatively small community. With the help of the accelerometer sensor and the Google Mapping service, information of the location and the activity data will be send to the remote server for the downstream processing. The experimental result has shown that SA (Sum-vector of all axes) value of 2.5 g is the threshold value to distinguish the falling from other activities. A three-stage detection algorithm was adopted to increase the accuracy of the real alarm, and the accuracy rate of our system was more than 95%. With the further improvement, the falling detecting device which is low-cost, accurate and user-friendly would become more and more common in everyday life.

Preoperative Falls Predict Postoperative Falls, Functional Decline, and Surgical Complications.

PubMed

Kronzer, Vanessa L; Jerry, Michelle R; Ben Abdallah, Arbi; Wildes, Troy S; Stark, Susan L; McKinnon, Sherry L; Helsten, Daniel L; Sharma, Anshuman; Avidan, Michael S

2016-10-01

Falls are common and linked to morbidity. Our objectives were to characterize postoperative falls, and determine whether preoperative falls independently predicted postoperative falls (primary outcome), functional dependence, quality of life, complications, and readmission. This prospective cohort study included 7982 unselected patients undergoing elective surgery. Data were collected from the medical record, a baseline survey, and follow-up surveys approximately 30days and one year after surgery. Fall rates (per 100 person-years) peaked at 175 (hospitalization), declined to 140 (30-day survey), and then to 97 (one-year survey). After controlling for confounders, a history of one, two, and ≥three preoperative falls predicted postoperative falls at 30days (adjusted odds ratios [aOR] 2.3, 3.6, 5.5) and one year (aOR 2.3, 3.4, 6.9). One, two, and ≥three falls predicted functional decline at 30days (aOR 1.2, 2.4, 2.4) and one year (aOR 1.3, 1.5, 3.2), along with in-hospital complications (aOR 1.2, 1.3, 2.0). Fall history predicted adverse outcomes better than commonly-used metrics, but did not predict quality of life deterioration or readmission. Falls are common after surgery, and preoperative falls herald postoperative falls and other adverse outcomes. A history of preoperative falls should be routinely ascertained. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Thermal Inertia of Rocks and Rock Populations

NASA Technical Reports Server (NTRS)

Golombek, M. P.; Jakosky, B. M.; Mellon, M. T.

2001-01-01

The effective thermal inertia of rock populations on Mars and Earth is derived from a model of effective inertia versus rock diameter. Results allow a parameterization of the effective rock inertia versus rock abundance and bulk and fine component inertia. Additional information is contained in the original extended abstract.

Post-glacial rock avalanches in the Obersee Valley, Glarner Alps, Switzerland

NASA Astrophysics Data System (ADS)

Nagelisen, Jan; Moore, Jeffrey R.; Vockenhuber, Christoph; Ivy-Ochs, Susan

2015-06-01

The geological record of prehistoric rock avalanches provides invaluable data for assessing the hazard posed by these rare but destructive mass movements. Here we investigate two large rock avalanches in the Obersee valley of the Glarner Alps, Switzerland, providing detailed mapping of landslide and related Quaternary phenomena, revised volume estimates for each event, and surface exposure dating of rock avalanche deposits. The Rautispitz rock avalanche originated from the southern flank of the Obersee valley, releasing approximately 91 million m3 of limestone on steeply-dipping bedding planes. Debris had maximum horizontal travel distance of ~ 5000 m, a fahrboeschung angle (relating fall height to length) of 18°, and was responsible for the creation of Lake Obersee; deposits are more than 130 m thick in places. The Platten rock avalanche encompassed a source volume of 11 million m3 sliding from the northern flank of the Obersee valley on similar steeply-dipping limestone beds (bedrock forms a syncline under the valley). Debris had a maximum horizontal travel distance of 1600 m with a fahrboeschung angle of 21°, and is more than 80 m thick in places. Deposits of the Platten rock avalanche are superposed atop those from the Rautispitz event at the end of the Obersee valley where they dam Lake Haslensee. Runout for both events was simulated using the dynamic analysis code DAN3D; results showed excellent match to mapped deposit extents and thickness and helped confirm the hypothesized single-event failure scenarios. 36Cl cosmogenic nuclide surface exposure dating of 13 deposited boulders revealed a Younger Dryas age of 12.6 ± 1.0 ka for the Rautispitz rock avalanche and a mid-Holocene age of 6.1 ± 0.8 ka for the Platten rock avalanche. A seismological trigger is proposed for the former event due to potentially correlated turbidite deposits in nearby Lake Zurich.

Jing and King Receive Mineral and Rock Physics Graduate Research Awards

NASA Astrophysics Data System (ADS)

2012-02-01

Zhicheng Jing and Daniel King have been awarded the 2011 Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origin and physical properties. Jing's thesis is entitled “Equation of state of silicate liquids.” King's thesis is entitled “Stress-driven melt segregation and reactive melt infiltration in partially molten rocks deformed in torsion with applications to melt extraction from Earth's mantle.” They both were formally presented with the award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif.

Genetic characterization of naturally spawned Snake River fall-run Chinook salmon

USGS Publications Warehouse

Marshall, A.R.; Blankenship, H.L.; Connor, W.P.

1999-01-01

We sampled juvenile Snake River chinook salmon Oncorhynchus tshawytscha to genetically characterize the endangered Snake River fall-run population. Juveniles from fall and spring–summer lineages coexisted in our sampling areas but were differentiated by large allozyme allele frequency differences. We sorted juveniles by multilocus genotypes into putative fall and spring lineage subsamples and determined lineage composition using maximum likelihood estimation methods. Paired sMEP-1* and PGK-2* genotypes—encoding malic enzyme (NADP+) and phosphoglycerate kinase, respectively—were very effective for sorting juveniles by lineage, and subsamples estimated to be 100% fall lineage were obtained in four annual samples. We examined genetic relationships of these fall lineage juveniles with adjacent populations from the Columbia River and from Lyons Ferry Hatchery, which was established to perpetuate the Snake River fall-run population. Our samples of naturally produced Snake River fall lineage juveniles were most closely aligned with Lyons Ferry Hatchery samples. Although fall-run strays of Columbia River hatchery origin found on spawning grounds threaten the genetic integrity of the Snake River population, juvenile samples (a) showed distinctive patterns of allelic diversity, (b) were differentiated from Columbia River populations, and (c) substantiate earlier conclusions that this population is an important genetic resource. This first characterization of naturally produced Snake River fall chinook salmon provides a baseline for monitoring and recovery planning.

Continuous Monitoring of Pin Tip Wear and Penetration into Rock Surface Using a New Cerchar Abrasivity Testing Device

NASA Astrophysics Data System (ADS)

Hamzaban, Mohammad-Taghi; Memarian, Hossein; Rostami, Jamal

2014-03-01

Evaluation of rock abrasivity is important when utilizing mechanized excavation in various mining and civil projects in hard rock. This is due to the need for proper selection of the rock cutting tools, estimation of the tool wear, machine downtime for cutter change, and costs. The Cerchar Abrasion Index (CAI) test is one of the simplest and most widely used methods for evaluating rock abrasivity. In this study, a new device for the determination of frictional forces and depth of pin penetration into the rock surface during a Cerchar test is discussed. The measured parameters were used to develop an analytical model for calculation of the size of the wear flat (and hence a continuous measure of CAI as the pin moves over the sample) and pin tip penetration into the rock during the test. Based on this model, continuous curves of CAI changes and pin tip penetration into the rock were plotted. Results of the model were used for introduction of a new parameter describing rock-pin interaction and classification of rock abrasion.

Fear of falling as seen in the Multidisciplinary falls consultation.

PubMed

Gaxatte, C; Nguyen, T; Chourabi, F; Salleron, J; Pardessus, V; Delabrière, I; Thévenon, A; Puisieux, F

2011-06-01

Fear of falling may be as debilitating as the fall itself, leading to a restriction in activities and even a loss of autonomy. The main objective was to evaluate the prevalence of the fear of falling among elderly fallers. The secondary objectives were to determine the factors associated with the fear of falling and evaluate the impact of this fear on the activity "getting out of the house". Prospective study conducted between 1995 and 2006 in which fallers and patients at high risk for falling were seen at baseline by the multidisciplinary falls consultation team (including a geriatrician, a neurologist and a physical medicine and rehabilitation physician) and then, again 6 month later, by the same geriatrician. The fear of falling was evaluated with a yes/no question: "are you afraid of falling?". Out of 635 patients with a mean age of 80.6 years, 502 patients (78%) expressed a fear of falling. Patients with fear of falling were not older than those who did not report this fear, but the former were mostly women (P<0,001), who experienced more falls in the 6 months preceding the consultation (P=0.01), reported more frequently a long period of time spent on the floor after a fall (P<0.001), had more balance disorders (P=0.002) and finally, were using more frequently a walking technical aid (P=0.02). Patients with fear of falling were not going out alone as much as the fearless group (31% vs 53%, P<0.0001). Eighty-two percent of patients in the fearful group admitted to avoiding going out because they were afraid of falling. The strong prevalence of the fear of falling observed in this population and its consequences in terms of restricted activities justifies systematically screening for it in fallers or patients at risk for falling. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Laboratory scale micro-seismic monitoring of rock faulting and injection-induced fault reactivation

NASA Astrophysics Data System (ADS)

Sarout, J.; Dautriat, J.; Esteban, L.; Lumley, D. E.; King, A.

2017-12-01

The South West Hub CCS project in Western Australia aims to evaluate the feasibility and impact of geosequestration of CO2 in the Lesueur sandstone formation. Part of this evaluation focuses on the feasibility and design of a robust passive seismic monitoring array. Micro-seismicity monitoring can be used to image the injected CO2plume, or any geomechanical fracture/fault activity; and thus serve as an early warning system by measuring low-level (unfelt) seismicity that may precede potentially larger (felt) earthquakes. This paper describes laboratory deformation experiments replicating typical field scenarios of fluid injection in faulted reservoirs. Two pairs of cylindrical core specimens were recovered from the Harvey-1 well at depths of 1924 m and 2508 m. In each specimen a fault is first generated at the in situ stress, pore pressure and temperature by increasing the vertical stress beyond the peak in a triaxial stress vessel at CSIRO's Geomechanics & Geophysics Lab. The faulted specimen is then stabilized by decreasing the vertical stress. The freshly formed fault is subsequently reactivated by brine injection and increase of the pore pressure until slip occurs again. This second slip event is then controlled in displacement and allowed to develop for a few millimeters. The micro-seismic (MS) response of the rock during the initial fracturing and subsequent reactivation is monitored using an array of 16 ultrasonic sensors attached to the specimen's surface. The recorded MS events are relocated in space and time, and correlate well with the 3D X-ray CT images of the specimen obtained post-mortem. The time evolution of the structural changes induced within the triaxial stress vessel is therefore reliably inferred. The recorded MS activity shows that, as expected, the increase of the vertical stress beyond the peak led to an inclined shear fault. The injection of fluid and the resulting increase in pore pressure led first to a reactivation of the pre

How are the costs of care for medical falls distributed? The costs of medical falls by component of cost, timing, and injury severity.

PubMed

Bohl, Alex A; Phelan, Elizabeth A; Fishman, Paul A; Harris, Jeffrey R

2012-10-01

To examine the components of cost that drive increased total costs after a medical fall over time, stratified by injury severity. We used 2004-2007 cost and utilization data for persons enrolled in an integrated care delivery system. We used a longitudinal cohort study design, where each individual provides 2-3 years of administrative data grouped into 3-month intervals relative to an index date. We identified 8,969 medical fallers through International Classification of Diseases, 9th Revision, codes and E-Codes and used 8,956 nonfaller controls, identified through age and gender frequency matching. Total costs were partitioned into 7 components: inpatient, outpatient, emergency, radiology, pharmacy, postacute care, and "other." The large increase in costs after a hospitalized fall is mainly associated with inpatient and postacute care components. The spike in costs after a nonhospitalized fall is attributable to outpatient and "other" (e.g., ambulatory surgery or community health services) components. Hospitalized fallers' inpatient, emergency, postacute care, outpatient, and radiology costs are not always greater than those for nonhospitalized fallers. Components associated with increased costs after a medical fall vary over time and by injury severity. Future studies should compare if delivering certain acute and postacute health services improve health and reduce cost trajectories after a medical fall more than others. Additionally, since the older adult population and the problem of falls are growing, health care delivery systems should develop standardized methodology to monitor medical fall rates.

Rethinking Little Rock: The Cold War Politics of School Integration in the United States

ERIC Educational Resources Information Center

Dejong-Lambert, William

2007-01-01

Though the impact of the cold war on the civil rights movement continued long after the desegregation crisis in Little Rock, the timing of the events in Arkansas, particularly the events at Central High School, constituted a unique moment in the history of the cold war. Up until the fall of 1957, the Soviet Union had been perceived as less…

SisFall: A Fall and Movement Dataset

PubMed Central

Sucerquia, Angela; López, José David; Vargas-Bonilla, Jesús Francisco

2017-01-01

Research on fall and movement detection with wearable devices has witnessed promising growth. However, there are few publicly available datasets, all recorded with smartphones, which are insufficient for testing new proposals due to their absence of objective population, lack of performed activities, and limited information. Here, we present a dataset of falls and activities of daily living (ADLs) acquired with a self-developed device composed of two types of accelerometer and one gyroscope. It consists of 19 ADLs and 15 fall types performed by 23 young adults, 15 ADL types performed by 14 healthy and independent participants over 62 years old, and data from one participant of 60 years old that performed all ADLs and falls. These activities were selected based on a survey and a literature analysis. We test the dataset with widely used feature extraction and a simple to implement threshold based classification, achieving up to 96% of accuracy in fall detection. An individual activity analysis demonstrates that most errors coincide in a few number of activities where new approaches could be focused. Finally, validation tests with elderly people significantly reduced the fall detection performance of the tested features. This validates findings of other authors and encourages developing new strategies with this new dataset as the benchmark. PMID:28117691

SisFall: A Fall and Movement Dataset.

PubMed

Sucerquia, Angela; López, José David; Vargas-Bonilla, Jesús Francisco

2017-01-20

Research on fall and movement detection with wearable devices has witnessed promising growth. However, there are few publicly available datasets, all recorded with smartphones, which are insufficient for testing new proposals due to their absence of objective population, lack of performed activities, and limited information. Here, we present a dataset of falls and activities of daily living (ADLs) acquired with a self-developed device composed of two types of accelerometer and one gyroscope. It consists of 19 ADLs and 15 fall types performed by 23 young adults, 15 ADL types performed by 14 healthy and independent participants over 62 years old, and data from one participant of 60 years old that performed all ADLs and falls. These activities were selected based on a survey and a literature analysis. We test the dataset with widely used feature extraction and a simple to implement threshold based classification, achieving up to 96% of accuracy in fall detection. An individual activity analysis demonstrates that most errors coincide in a few number of activities where new approaches could be focused. Finally, validation tests with elderly people significantly reduced the fall detection performance of the tested features. This validates findings of other authors and encourages developing new strategies with this new dataset as the benchmark.

Falls efficacy, postural balance, and risk for falls in older adults with falls-related emergency department visits: prospective cohort study.

PubMed

Pua, Yong-Hao; Ong, Peck-Hoon; Clark, Ross Allan; Matcher, David B; Lim, Edwin Choon-Wyn

2017-12-21

Risk for falls in older adults has been associated with falls efficacy (self-perceived confidence in performing daily physical activities) and postural balance, but available evidence is limited and mixed. We examined the interaction between falls efficacy and postural balance and its association with future falls. We also investigated the association between falls efficacy and gait decline. Falls efficacy, measured by the Modified Falls Efficacy Scale (MFES), and standing postural balance, measured using computerized posturography on a balance board, were obtained from 247 older adults with a falls-related emergency department visit. Six-month prospective fall rate and habitual gait speed at 6 months post baseline assessment were also measured. In multivariable proportional odds analyses adjusted for potential confounders, falls efficacy modified the association between postural balance and fall risk (interaction P = 0.014): increasing falls efficacy accentuated the increased fall risk related to poor postural balance. Low baseline falls efficacy was strongly predictive of worse gait speed (0.11 m/s [0.06 to 0.16] slower gait speed per IQR decrease in MFES; P < 0.001). Older adults with high falls efficacy but poor postural balance were at greater risk for falls than those with low falls efficacy; however, low baseline falls efficacy was strongly associated with worse gait function at follow-up. Further research into these subgroups of older adults is warranted. ClinicalTrials.gov identifier: NCT01713543 .

Niagara Falls Storage Site annual environmental report for calendar year 1991, Lewiston, New York. [Niagara Falls Storage Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-09-01

This document describes the environmental monitoring program at the Niagara Falls Storage Site (NFSS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at NFSS began in 1981. The site is owned by the US Department of Energy (DOE) and is assigned to the DOE Formerly Utilized Sites Remedial Action Program (FUSRAP). FUSRAP is a program to decontaminate or otherwise control sites where residual radioactive materials remain from the early years of the nation's atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The environmental monitoring program atmore » NFSS includes sampling networks for radon concentrations in air; external gamma radiation exposure; and total uranium and radium-226 concentrations in surface water, sediments, and groundwater. Additionally, several nonradiological parameters including seven metals are routinely measured in groundwater. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE orders. Environmental standards are established to protect public health and the environment.« less

Diminishing friction of joint surfaces as initiating factor for destabilising permafrost rocks?

NASA Astrophysics Data System (ADS)

Funk, Daniel; Krautblatter, Michael

2010-05-01

Degrading alpine permafrost due to changing climate conditions causes instabilities in steep rock slopes. Due to a lack in process understanding, the hazard is still difficult to asses in terms of its timing, location, magnitude and frequency. Current research is focused on ice within joints which is considered to be the key-factor. Monitoring of permafrost-induced rock failure comprises monitoring of temperature and moisture in rock-joints. The effect of low temperatures on the strength of intact rock and its mechanical relevance for shear strength has not been considered yet. But this effect is signifcant since compressive and tensile strength is reduced by up to 50% and more when rock thaws (Mellor, 1973). We hypotheisze, that the thawing of permafrost in rocks reduces the shear strength of joints by facilitating the shearing/damaging of asperities due to the drop of the compressive/tensile strength of rock. We think, that decreasing surface friction, a neglected factor in stability analysis, is crucial for the onset of destabilisation of permafrost rocks. A potential rock slide within the permafrost zone in the Wetterstein Mountains (Zugspitze, Germany) is the basis for the data we use for the empirical joint model of Barton (1973) to estimate the peak shear strength of the shear plane. Parameters are the JRC (joint roughness coefficient), the JCS (joint compressive strength) and the residual friction angle (φr). The surface roughness is measured in the field with a profile gauge to create 2D-profiles of joint surfaces. Samples of rock were taken to the laboratory to measure compressive strength using a high-impact Schmidt-Hammer under air-dry, saturated and frozen conditions on weathered and unweathered surfaces. Plugs where cut out of the rock and sand blasted for shear tests under frozen and unfrozen conditions. Peak shear strength of frozen and unfrozen rocks will be calculated using Barton's model. First results show a mean decrease of compressive

Rock pushing and sampling under rocks on Mars

USGS Publications Warehouse

Moore, H.J.; Liebes, S.; Crouch, D.S.; Clark, L.V.

1978-01-01

Viking Lander 2 acquired samples on Mars from beneath two rocks, where living organisms and organic molecules would be protected from ultraviolet radiation. Selection of rocks to be moved was based on scientific and engineering considerations, including rock size, rock shape, burial depth, and location in a sample field. Rock locations and topography were established using the computerized interactive video-stereophotogrammetric system and plotted on vertical profiles and in plan view. Sampler commands were developed and tested on Earth using a full-size lander and surface mock-up. The use of power by the sampler motor correlates with rock movements, which were by plowing, skidding, and rolling. Provenance of the samples was determined by measurements and interpretation of pictures and positions of the sampler arm. Analytical results demonstrate that the samples were, in fact, from beneath the rocks. Results from the Gas Chromatograph-Mass Spectrometer of the Molecular Analysis experiment and the Gas Exchange instrument of the Biology experiment indicate that more adsorbed(?) water occurs in samples under rocks than in samples exposed to the sun. This is consistent with terrestrial arid environments, where more moisture occurs in near-surface soil un- der rocks than in surrounding soil because the net heat flow is toward the soil beneath the rock and the rock cap inhibits evaporation. Inorganic analyses show that samples of soil from under the rocks have significantly less iron than soil exposed to the sun. The scientific significance of analyses of samples under the rocks is only partly evaluated, but some facts are clear. Detectable quantities of martian organic molecules were not found in the sample from under a rock by the Molecular Analysis experiment. The Biology experiments did not find definitive evidence for Earth-like living organisms in their sample. Significant amounts of adsorbed water may be present in the martian regolith. The response of the soil

Rippability Assessment of Weathered Sedimentary Rock Mass using Seismic Refraction Methods

NASA Astrophysics Data System (ADS)

Ismail, M. A. M.; Kumar, N. S.; Abidin, M. H. Z.; Madun, A.

2018-04-01

Rippability or ease of excavation in sedimentary rocks is a significant aspect of the preliminary work of any civil engineering project. Rippability assessment was performed in this study to select an available ripping machine to rip off earth materials using the seismic velocity chart provided by Caterpillar. The research area is located at the proposed construction site for the development of a water reservoir and related infrastructure in Kampus Pauh Putra, Universiti Malaysia Perlis. The research was aimed at obtaining seismic velocity, P-wave (Vp) using a seismic refraction method to produce a 2D tomography model. A 2D seismic model was used to delineate the layers into the velocity profile. The conventional geotechnical method of using a borehole was integrated with the seismic velocity method to provide appropriate correlation. The correlated data can be used to categorize machineries for excavation activities based on the available systematic analysis procedure to predict rock rippability. The seismic velocity profile obtained was used to interpret rock layers within the ranges labelled as rippable, marginal, and non-rippable. Based on the seismic velocity method the site can be classified into loose sand stone to moderately weathered rock. Laboratory test results shows that the site’s rock material falls between low strength and high strength. Results suggest that Caterpillar’s smallest ripper, namely, D8R, can successfully excavate materials based on the test results integration from seismic velocity method and laboratory test.

CHARACTER AND REGIONAL SIGNIFICANCE OF GREAT FALLS TECTONIC ZONE, EAST-CENTRAL IDAHO AND WEST-CENTRAL MONTANA.

USGS Publications Warehouse

O'Neill, J. Michael; Lopez, David A.

1985-01-01

The Great Falls tectonic zone, here named, is a belt of diverse northeast-trending geologic features that can be traced from the Idaho batholith in the Cordilleran miogeocline, across thrust-belt structures and basement rocks of west-central and southwestern Montana, through cratonic rocks of central Montana, and into southwestern-most Saskatchewan, Canada. Geologic mapping in east-central Idaho and west-central Montana has outlined a continuous zone of high-angle faults and shear zones. Recurrent fault movement in this zone and strong structural control over igneous intrusion suggest a fundamental tectonic feature that has influenced the tectonic development of the Idaho-Montana area from a least middle Proterozoic time to the present. Refs.

Falls in People with Multiple Sclerosis Compared with Falls in Healthy Controls

PubMed Central

Mazumder, Rajarshi; Murchison, Charles; Bourdette, Dennis; Cameron, Michelle

2014-01-01

Objective To compare the risk, circumstances, consequences and causes of prospectively recorded falls between people with multiple sclerosis (PwMS) and healthy controls of similar age and gender. Methods 58 PwMS and 58 healthy controls, who are community-dwelling, were recruited in this 6-month prospective cohort study. 90% of PwMS and 84% of healthy controls completed the study. Participants counted falls prospectively using fall calendars and noted fall location, fall-related injuries, and the cause of the falls. Kaplan Meier survival analysis and log-rank tests were performed to compare the distributions of survival without falling between PwMS and healthy controls. Results 40.8% of controls and 71.2% of PwMS fell at least once. 48.1% of PwMS and 18.4% of healthy controls fell at least twice. 42.3% of PwMS and 20.4% of health controls sustained a fall-related injury. After adjusting for age and gender, the time to first fall (HR: 1.87, p = 0.033) and the time to recurrent falls (HR: 2.87, p = 0.0082) were significantly different between PwMS and healthy controls. PwMS reported an almost equal number of falls inside and outside, 86% of the falls in healthy controls were outside. Healthy controls were more likely to fall due to slipping on a slippery surface (39.5% vs 10.4%). PwMS more often attributed falls to distraction (31% vs 7%) and uniquely attributed falls to fatigue or heat. Conclusions Fall risk, circumstances, consequences, and causes are different for PwMS than for healthy people of the same age and gender. PwMS fall more, are more likely to be injured by a fall, and often fall indoors. PwMS, but not healthy controls, frequently fall because they are distracted, fatigued or hot. PMID:25254633

Age-associated striatal dopaminergic denervation and falls in community-dwelling subjects

PubMed Central

Bohnen, Nicolaas I.; Muller, Martijn L. T. M.; Kuwabara, Hiroto; Cham, Rakié; Constantine, Gregory M.; Studenski, Stephanie A.

2016-01-01

Older adults have a high prevalence of gait and balance disturbances and falls. Normal aging is associated with significant striatal dopaminergic denervation, which might be a previously unrecognized additional contributor to geriatric falls. This study investigated the relationship between the severity of age-associated striatal dopaminergic denervation (AASDD) and falls in community-dwelling subjects. Community-dwelling subjects who did not have a clinical diagnosis to explain falls (n = 77: 43 female, 34 male; mean age 61.4 +/− 16.4; range 20–85) completed clinical assessment and brain dopamine transporter (DAT) [11C]beta-CFT (2-beta-carbomethoxy-3beta-(4-fluorophenyl) tropane) positron emission tomography imaging followed by 6 months of prospective fall monitoring using diaries. Results showed a significant inverse relationship between striatal DAT activity and age (r = −0.82, p < 0.001). A total of 26 subjects (33.8%) reported at least one fall, with 5 subjects (6.5%) reporting two or more falls. While no significant difference was noted in striatal DAT activity between nonfallers (n = 51) and fallers (n = 26; f = 0.02, not significant), striatal DAT activity was modestly reduced in the small subgroup of recurrent fallers compared with the other subjects (f = 5.07, p < 0.05). Findings indicate that AASDD does not explain isolated self-reported falls in community-dwelling subjects. However, it may be a contributing factor in the small subgroup of subjects with recurrent falls. PMID:20157861

A survey of lunar rock types and comparison of the crusts of earth and moon

NASA Technical Reports Server (NTRS)

Wood, J. A.

1977-01-01

The principal known types of lunar rocks are briefly reviewed, and their chemical relationships discussed. In the suite of low-KREEP highland rocks, Fe/(Fe + Mg) in the normative mafic minerals increases and the albite content of normative plagio-clase decreases as the total amount of normative plagioclase increases, the opposite of the trend predicted by the Bowen reaction principle. The distribution of compositions of rocks from terrestrial layered mafic intrusives is substantially different: here the analyses fall in several discrete clusters (anorthositic rocks, norites, granophyres and ferrogabbros, ultramafics), and the chemical trends noted above are not reproduced. It is suggested that the observed trends in lunar highland rocks could be produced by crystal fractionation in a deep global surface magma system if (1) plagiociase tended to float, upon crystallization, and (2) the magma was kept agitated and well mixed (probably by thermal convection) until crystallization was far advanced and relatively little residual liquid was left. After the crustal system solidified, but before extensive cooling had developed a thick, strong lithosphere, mantle convection was able to draw portions of the lunar anorthositic crust down into the mantle.

Monitoring and Evaluation of Yearling Fall Chinook Salmon (Oncorhynchus tshawytscha) Released from Acclimation Facilities Upstream of Lower Granite Dam; 2000 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rocklage, Stephen J.; Kellar, Dale S.

2005-07-01

The Nez Perce Tribe, in cooperation with the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife, conducted monitoring and evaluation studies on Lyons Ferry Hatchery reared yearling fall Chinook salmon Oncorhynchus tshawytscha that were acclimated and released at three Fall Chinook Acclimation Project sites upstream of Lower Granite Dam along with yearlings released on-station from Lyons Ferry Hatchery in 2000. This was the fifth year of a long-term project to supplement natural spawning populations of Snake River stock fall Chinook salmon upstream of Lower Granite Dam. The 397,339 yearlings released from the Fall Chinook Acclimation Projectmore » facilities were short of the 450,000 fish quota. We use Passive Integrated Transponder (PIT) tag technology to monitor the primary performance measures of survival to mainstem dams and migration timing. We also monitor size, condition and tag/mark retention at release. We released 7,477 PIT tagged yearlings from Pittsburg Landing, 7,421 from Big Canyon and 2,488 from Captain John Rapids. The Washington Department of Fish and Wildlife released 980 PIT tagged yearlings from Lyons Ferry Hatchery. Fish health sampling indicated that, overall, bacterial kidney disease levels could be considered relatively low. Compared to prior years, Quantitative Health Assessment Indices were relatively low at Big Canyon and Captain John Rapids and about average at Pittsburg Landing and Lyons Ferry Hatchery. Mean fork lengths (95% confidence interval) of the PIT tagged groups ranged from 157.7 mm (157.3-158.1 mm) at Big Canyon to 172.9 mm (172.2-173.6 mm) at Captain John Rapids. Mean condition factors ranged from 1.06 at Captain John Rapids and Lyons Ferry Hatchery to 1.12 at Big Canyon. Estimated survival (95% confidence interval) of PIT tagged yearlings from release to Lower Granite Dam ranged from 87.0% (84.7-89.4%) for Pittsburg Landing to 95.2% (91.5-98.9%) for Captain John Rapids. Estimated survival from

Monitoring and Evaluation of Yearling Fall Chinook Salmon (Oncorhynchus tshawytscha) Released from Acclimation Facilities Upstream of Lower Granite Dam; 2001 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rocklage, Stephen J.; Kellar, Dale S.

2005-07-01

The Nez Perce Tribe, in cooperation with the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife, conducted monitoring and evaluation studies on Lyons Ferry Hatchery reared yearling fall Chinook salmon Oncorhynchus tshawytscha that were acclimated and released at three Fall Chinook Acclimation Project sites upstream of Lower Granite Dam along with yearlings released on-station from Lyons Ferry Hatchery in 2001. This was the sixth year of a long-term project to supplement natural spawning populations of Snake River stock fall Chinook salmon upstream of Lower Granite Dam. The 318,932 yearlings released from the Fall Chinook Acclimation Projectmore » facilities were short of the 450,000 fish quota. We use Passive Integrated Transponder (PIT) tag technology to monitor the primary performance measures of survival to mainstem dams and migration timing. We also monitor size, condition and tag/mark retention at release. We released 7,503 PIT tagged yearlings from Pittsburg Landing, 7,499 from Big Canyon and 2,518 from Captain John Rapids. The Washington Department of Fish and Wildlife released 991 PIT tagged yearlings from Lyons Ferry Hatchery. Fish health sampling indicated that, overall, bacterial kidney disease levels could be considered relatively low. Compared to prior years, Quantitative Health Assessment Indices were relatively low at Big Canyon and Captain John Rapids and about average at Pittsburg Landing and Lyons Ferry Hatchery. Mean fork lengths (95% confidence interval) of the PIT tagged groups ranged from 155.4 mm (154.7-156.1 mm) at Captain John Rapids to 171.6 mm (170.7-172.5 mm) at Lyons Ferry Hatchery. Mean condition factors ranged from 1.02 at Lyons Ferry Hatchery to 1.16 at Big Canyon and Captain John Rapids. Estimated survival (95% confidence interval) of PIT tagged yearlings from release to Lower Granite Dam ranged from 74.4% (73.2-75.5%) for Big Canyon to 85.2% (83.5-87.0%) for Captain John Rapids. Estimated survival from

Optimal fall indicators for slip induced falls on a cross-slope.

PubMed

Domone, Sarah; Lawrence, Daniel; Heller, Ben; Hendra, Tim; Mawson, Sue; Wheat, Jonathan

2016-08-01

Slip-induced falls are among the most common cause of major occupational injuries in the UK as well as being a major public health concern in the elderly population. This study aimed to determine the optimal fall indicators for fall detection models which could be used to reduce the detrimental consequences of falls. A total of 264 kinematic variables covering three-dimensional full body model translation and rotational measures were analysed during normal walking, successful recovery from slips and falls on a cross-slope. Large effect sizes were found for three kinematic variables which were able to distinguish falls from normal walking and successful recovery. Further work should consider other types of daily living activities as results show that the optimal kinematic fall indicators can vary considerably between movement types. Practitioner Summary: Fall detection models are used to minimise the adverse consequences of slip-induced falls, a major public health concern. Optimal fall indicators were derived from a comprehensive set of kinematic variables for slips on a cross-slope. Results suggest robust detection of falls is possible on a cross-slope but may be more difficult than level walking.

The Cretaceous-Tertiary extinction: A lethal mechanism involving anhydrite target rocks

USGS Publications Warehouse

Brett, R.

1992-01-01

The Chicxulub Crater, Yucatan, Mexico, is a leading contender as the site for the impact event that caused the Cretaceous-Tertiary (K-T) extinctions. A considerable thickness of anhydrite (CaSO4) forms part of the target rock. High temperatures resulting from impact would drive SO2 off from the anhydrite. Hundreds of billions of tonnes of sulfuric acid aerosol would thus enter the stratosphere and cause considerable cooling of the Earth's surface, decrease photosynthesis by orders of magnitude, deplete the ozone layer, and permit increased UV radiation to reach the Earth's surface. Finally, the aerosol would fall back to Earth as acid rain and devastate land and some lacustrine biota and near-surface marine creatures. The presence of anhydrite in the Chicxulub target rock may thus help explain the many extinctions observed at the K-T boundary. ?? 1992.

Petrography and geochemistry of precambrian rocks from GT-2 and EE-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laughlin, A.W.; Eddy, A.

1977-08-01

During the drilling of GT-2 and EE-1, 27 cores totaling about 35 m were collected from the Precambrian section. Samples of each different lithology in each core were taken for petrographic and whole-rock major- and trace-element analyses. Whole-rock analyses are now completed on 37 samples. From these data four major Precambrian units were identified at the Fenton Hill site. Geophysical logs and cuttings were used to extrapolate between cores. The most abundant rock type is an extremely variable gneissic unit comprising about 75% of the rock penetrated. This rock is strongly foliated and may range compositionally from syenogranitic to tonaliticmore » over a few centimeters. The bulk of the unit falls within the monzogranite field. Interlayered with the gneiss is a ferrohastingsite-biotite schist which compositionally resembles a basaltic andesite. A fault contact between the schist and gneiss was observed in one core. Intrusive into this metamorphic complex are two igneous rocks. A leucocratic monzogranite occurs as at least two 15-m-thick dikes, and a biotite-granodiorite body was intercepted by 338 m of drill hole. Both rocks are unfoliated and equigranular. The biotite granodiorite is very homogeneous and is characterized by high modal contents of biotite and sphene and by high K/sub 2/O, TiO/sub 2/, and P/sub 2/O/sub 5/ contents. Although all of the cores examined show fractures, most of these are tightly sealed or healed. Calcite is the most abundant fracture filling mineral, but epidote, quartz, chlorite, clays or sulfides have also been observed. The degree of alteration of the essential minerals normally increases as these fractures are approached. The homogeneity of the biotite granodiorite at the bottom of GT-2 and the high degree of fracture filling ensure an ideal setting for the Hot Dry Rock Experiment.« less

Statistical analysis of the radon-222 potential of rocks in Virginia, U.S.A.

USGS Publications Warehouse

Brown, C. Erwin; Mose, D.G.; Mushrush, G.W.; Chrosniak, C.E.

1992-01-01

More than 3,200 indoor radon-222 (222Rn) measurements were made seasonally in an area of about 1,000 square kilometers of the Coastal Plain and Piedmont physiographic provinces in Virginia, U.S.A. Results of these measurements indicate that some geological units are associated, on the average, with twice as much indoor222Rn as other geological units, and that indoor222Rn varies seasonally. The Kruskal-Wallis test was used to test whether indoor222Rn concentrations for data gathered over the winter and summer seasons differ significantly by rock unit. The tests concluded that indoor222Rn concentrations for different rock units were not equal at the 5-percent significance level. The rocks associated with the highest median indoor222Rn concentration are specific rocks in the Mesozoic Culpeper basin, including shale and siltstone units with Jurassic diabase intrusives, and mica schists in the Piedmont physiographic province. The pre-Triassic Peters Creek Schist has the highest ranking in terms of indoor222Rn concentration. The rocks associated with the lowest indoor222Rn concentrations include coastal plain sediments, the Occoquan Granite, Falls Church Tonalite, Piney Branch Mafic and Ultramafic complex, and unnamed mafic and ultramafic inclusions, respectively. The rocks have been ranked according to observed222Rn concentration by transforming the average rank of indoor222Rn concentrations to z scores. ?? 1992 Springer-Verlag New York Inc.

Oxygen fugacity of gases and rocks from Momotombo Volcano, Nicaragua: Application to volcanological monitoring

NASA Astrophysics Data System (ADS)

Benhamou, G.; Allard, P.; Sabroux, J. C.; Vitter, G.; Dajlevic, D.; Creusot, A.

1988-12-01

The oxygen fugacity (fO2) and the fO2 versus T°C relationship of high-temperature (600°-860°C) gas emissions from Momotombo volcano, Nicaragua, was determined from both field electrochemical measurements (electrolytic cell assembly) and thermodynamic computations on gas samples collected between 1978 and 1985. It was then compared with the intrinsic fO2 of fresh and altered lavas from the last eruption (1905), as measured between 500° and 1100°C in laboratory. The electrochemical results show that the oxygen fugacity of Momotombo fumaroles, at equivalent temperature, is much higher than that of the fresh 1905 lava (˜FMQ buffer) and closer to that of their altered wall rocks (˜FMQ buffer). The equilibrium O2 fugacities calculated from the chemistry of gas samples confirm this pattern. However, they suggest that the gas mixtures preserve the (variable) memory of a higher thermal equilibrium achieved at depth, under temperature and fO2 conditions of up to 1050°C and 10-9.0 atm, respectively, which correspond to the cross over between the fO2-T gas and lava trends. These data thus support the idea that Momotombo volcanic gases, released in a period of increasing activity, escape from a shallow magma body before suffering a variable oxidation during their ascent through both unbuffered cooling and reactions with environmental fluids and rocks. This late oxidation is weaker at central fumaroles than at peripherical ones. While between 1978 and 1985 the temperature of the hottest fumarole increased from 750° to 865°-900°C, the equilibrium fO2 of the gas decreased by nearly one order of magnitude (at comparable equilibrium temperature). Such an evolution presumably reflects an increasing connection between the surface exhalations and the magma degassing at depth along with time. This work underlines the possibility of monitoring the processes of magma ascent and gas-magma separation within a volcano before an eruption by continuously recording the changes of

2009 Mineral and Rock Physics Graduate Research Award to Yu and Austin

NASA Astrophysics Data System (ADS)

2010-04-01

Yonggang Yu and Nicholas J. Austin have been awarded the Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origin and physical properties. Yu's thesis is entitled “Structure properties and phase transitions in earth minerals: A first principles study.” Austin's thesis is entitled “Grain size evolution and strain localization in deformed marbles.” They were both formally presented with the award at the Mineral and Rock Physics focus group reception during the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif.

Increasing fall risk awareness using wearables: A fall risk awareness protocol.

PubMed

Danielsen, Asbjørn; Olofsen, Hans; Bremdal, Bernt Arild

2016-10-01

Each year about a third of elderly aged 65 or older experience a fall. Many of these falls may have been avoided if fall risk assessment and prevention tools where available in a daily living situation. We identify what kind of information is relevant for doing fall risk assessment and prevention using wearable sensors in a daily living environment by investigating current research, distinguishing between prospective and context-aware fall risk assessment and prevention. Based on our findings, we propose a fall risk awareness protocol as a fall prevention tool integrating both wearables and ambient sensing technology into a single platform. Copyright © 2016. Published by Elsevier Inc.

Stochastic analysis of motor-control stability, polymer based force sensing, and optical stimulation as a preventive measure for falls

NASA Astrophysics Data System (ADS)

Landrock, Clinton K.

Falls are the leading cause of all external injuries. Outcomes of falls include the leading cause of traumatic brain injury and bone fractures, and high direct medical costs in the billions of dollars. This work focused on developing three areas of enabling component technology to be used in postural control monitoring tools targeting the mitigation of falls. The first was an analysis tool based on stochastic fractal analysis to reliably measure levels of motor control. The second focus was on thin film wearable pressure sensors capable of relaying data for the first tool. The third was new thin film advanced optics for improving phototherapy devices targeting postural control disorders. Two populations, athletes and elderly, were studied against control groups. The results of these studies clearly show that monitoring postural stability in at-risk groups can be achieved reliably, and an integrated wearable system can be envisioned for both monitoring and treatment purposes. Keywords: electro-active polymer, ionic polymer-metal composite, postural control, motor control, fall prevention, sports medicine, fractal analysis, physiological signals, wearable sensors, phototherapy, photobiomodulation, nano-optics.

Fall Protection Introduction, #33462

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chochoms, Michael

The proper use of fall prevention and fall protection controls can reduce the risk of deaths and injuries caused by falls. This course, Fall Protection Introduction (#33462), is designed as an introduction to various types of recognized fall prevention and fall protection systems at Los Alamos National Laboratory (LANL), including guardrail systems, safety net systems, fall restraint systems, and fall arrest systems. Special emphasis is given to the components, inspection, care, and storage of personal fall arrest systems (PFASs). This course also presents controls for falling object hazards and emergency planning considerations for persons who have fallen.

Kraus Receives 2012 Mineral and Rock Physics Graduate Research Award

NASA Astrophysics Data System (ADS)

2013-08-01

Richard Kraus received the 2012 Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origins and physical properties. Kraus's thesis is entitled "On the thermodynamics of planetary impact events." He was formally presented with the award at the 2012 AGU Fall Meeting, held 3-7 December in San Francisco, Calif.

Flowpath independent monitoring of reductive dechlorination potential in a fractured rock aquifer

USGS Publications Warehouse

Bradley, P.M.; Lacombe, P.J.; Imbrigiotta, T.E.; Chapelle, F.H.; Goode, D.J.

2009-01-01

The flowpath dependent approaches that are typically employed to assess biodegradation of chloroethene contaminants in unconsolidated aquifers are problematic in fractured rock settings, due to difficulties defining discrete groundwater flowpaths in such systems. In this study, the variation in the potential for chloroethene biodegradation with depth was evaluated in a fractured rock aquifer using two flowpath independent lines of field evidence: (1) the presence of the three biochemical prerequisites [electron donor(s), chloroethene electron acceptor(s), and chlororespiring microorganism(s)] for efficient chloroethene chlororespiration and (2) the in situ accumulation of chloroethene reductive dechlorination daughter products. The validity of this approach was assessed by comparing field results with the results of [1, 2- 14C] cis-DCE microcosm experiments. Microcosms were prepared with depth-specific core material, which was crushed and emplaced in discrete packer intervals for 1 year to allow colonization by the indigenous microbial community. Packer intervals characterized by significant electron donor concentrations, elevated numbers of chlororespiring microorganisms, and high reductive dechlorination product to parent contaminant ratios correlated well with the production of 14C-labeled reductive dechlorination products in the microcosm experiments. These results indicate that, in the absence of information on discrete groundwater flowpaths, a modified approach emphasizing flowpath independent lines of evidence can provide insight into the temporal and spatial variability of contaminant biodegradation in fractured rock systems. ?? 2009 National Ground Water Association.

Geoengineering Research for a Deep Underground Science and Engineering Laboratory in Sedimentary Rock

NASA Astrophysics Data System (ADS)

Mauldon, M.

2004-12-01

A process to identify world-class research for a Deep Underground Science and Engineering Laboratory (DUSEL) in the USA has been initiated by NSF. While allowing physicists to study, inter alia, dark matter and dark energy, this laboratory will create unprecedented opportunities for biologists to study deep life, geoscientists to study crustal processes and geoengineers to study the behavior of rock, fluids and underground cavities at depth, on time scales of decades. A substantial portion of the nation's future infrastructure is likely to be sited underground because of energy costs, urban crowding and vulnerability of critical surface facilities. Economic and safe development of subsurface space will require an improved ability to engineer the geologic environment. Because of the prevalence of sedimentary rock in the upper continental crust, much of this subterranean infrastructure will be hosted in sedimentary rock. Sedimentary rocks are fundamentally anisotropic due to lithology and bedding, and to discontinuities ranging from microcracks to faults. Fractures, faults and bedding planes create structural defects and hydraulic pathways over a wide range of scales. Through experimentation, observation and monitoring in a sedimentary rock DUSEL, in conjunction with high performance computational models and visualization tools, we will explore the mechanical and hydraulic characteristics of layered rock. DUSEL will permit long-term experiments on 100 m blocks of rock in situ, accessed via peripheral tunnels. Rock volumes will be loaded to failure and monitored for post-peak behavior. The response of large rock bodies to stress relief-driven, time-dependent strain will be monitored over decades. Large block experiments will be aimed at measurement of fluid flow and particle/colloid transport, in situ mining (incl. mining with microbes), remediation technologies, fracture enhancement for resource extraction and large scale long-term rock mass response to induced

The relationship between orthostatic hypotension and falling in older adults.

PubMed

Shaw, Brett H; Claydon, Victoria E

2014-02-01

Falls are devastating events and are the largest contributor towards injury-related hospitalization of older adults. Orthostatic hypotension (OH) represents an intrinsic risk factor for falls in older adults. OH refers to a significant decrease in blood pressure upon assuming an upright posture. Declines in blood pressure can reduce cerebral perfusion; this can impair consciousness, lead to dizziness, and increase the likelihood of a fall. Although theoretical mechanisms linking OH and falls exist, the magnitude of the association remains poorly characterized, possibly because of methodological differences between previous studies. The use of non-invasive beat-to-beat blood pressure monitoring has altered the way in which OH is now defined, and represents a substantial improvement for detecting OH that was previously unavailable in many studies. Additionally, there is a lack of consistency and standardization of orthostatic assessments and analysis techniques for interpreting blood pressure data. This review explores the previous literature examining the relationship between OH and falls. We highlight the impact of broadening the timing, degree, and overall duration of blood pressure measurements on the detection of OH. We discuss the types of orthostatic stress assessments currently used to evaluate OH and the various techniques capable of measuring these often transient blood pressure changes. Overall, we identify future solutions that may better clarify the relationship between OH and falling risk in order to gain a more precise understanding of potential mechanisms for falls in older adults.

An algorithm for retrieving rock-desertification from multispectral remote sensing images

NASA Astrophysics Data System (ADS)

Xia, Xueqi; Tian, Qingjiu; Liao, Yan

2009-06-01

Rock-desertification is a typical environmental and ecological problem in Southwest China. As remote sensing is an important means of monitoring spatial variation of rock-desertification, a method is developed for measurement and information retrieval of rock-desertification from multi-spectral high-resolution remote sensing images. MNF transform is applied to 4-band IKONOS multi-spectral remotely sensed data to reduce the number of spectral dimensions to three. In the 3-demension endmembers are extracted and analyzed. It is found that various vegetations group into a line defined as "vegetation line", in which "dark vegetations", such as coniferous forest and broadleaf forest, continuously change to "bright vegetations", such as grasses. It is presumed that is caused by deferent proportion of shadow mixed in leaves or branches in various types of vegetation. Normalized distance between the endmember of rocks and the vegetation line is defined as Geometric Rock-desertification Index (GRI), which was used to scale rock-desertification. The case study with ground truth validation in Puding, Guizhou province showed successes and the advantages of this method.

40 CFR 60.403 - Monitoring of emissions and operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Phosphate Rock Plants § 60.403 Monitoring of emissions and operations. (a) Any owner or operator subject to... of the gases discharged into the atmosphere from any phosphate rock dryer, calciner, or grinder. The span of this system shall be set at 40-percent opacity. (b) For ground phosphate rock storage and...

40 CFR 60.403 - Monitoring of emissions and operations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Phosphate Rock Plants § 60.403 Monitoring of emissions and operations. (a) Any owner or operator subject to... of the gases discharged into the atmosphere from any phosphate rock dryer, calciner, or grinder. The span of this system shall be set at 40-percent opacity. (b) For ground phosphate rock storage and...

40 CFR 60.403 - Monitoring of emissions and operations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Phosphate Rock Plants § 60.403 Monitoring of emissions and operations. (a) Any owner or operator subject to... of the gases discharged into the atmosphere from any phosphate rock dryer, calciner, or grinder. The span of this system shall be set at 40-percent opacity. (b) For ground phosphate rock storage and...

40 CFR 60.403 - Monitoring of emissions and operations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Phosphate Rock Plants § 60.403 Monitoring of emissions and operations. (a) Any owner or operator subject to... of the gases discharged into the atmosphere from any phosphate rock dryer, calciner, or grinder. The span of this system shall be set at 40-percent opacity. (b) For ground phosphate rock storage and...

Simulation and field monitoring of moisture in alpine rock walls during freeze-thaw events

NASA Astrophysics Data System (ADS)

Rode, Matthias; Sass, Oliver

2013-04-01

Detachment of rock fragments from alpine rockwalls is mainly assigned to frost weathering. However, the actual process of frost weathering as well as the contribution of further weathering processes (e.g. hydration, thermal fatigue) is poorly understood. Rock moisture distribution during freeze-thaw events is key to understanding weathering. For this purpose, different measuring systems were set up in two study areas (Dachstein - permafrost area (2700m a.s.l.) and Gesäuse - non permafrost area (900m a.s.l.), Styria, Austria) within the framework of the research project ROCKING ALPS (FWF-P24244). We installed small-scale 2D-geoelectric survey lines in north and in south facing rockwalls, supplemented by high resolution temperature and moisture sensors. Moisture is determined by means of resistivity measurements which are difficult to calibrate, but provide good time series. Additional novel moisture sensors were developed which use the heat capacity of the surrounding rock as a proxy of water content. These sensors give point readings from a defined depth and are independent from soluble salt contents. Pore water pressure occurring during freeze-thaw events is recorded by means of pressure transducers (piezometers). First results from the Dachstein show that short term latent heat effects during the phase change have crucial influence on the moisture content. These results are cross-checked by simulation calculations. Based on meteorologic and lithologic input values, the simulation routine calculates, in an iterative procedure, the hourly energy and water transport at different depths, the latter in the liquid and in the vapor phase. The calculated profile lines and chronological sequences of rock moisture allow - in combination with temperature data - to detect possible periods of active weathering. First simulations from the Gesäuse show that maximum values of pore saturation occur from May to September. The thresholds of the "classical" frost shattering theory

Unexplained Falls Are Frequent in Patients with Fall-Related Injury Admitted to Orthopaedic Wards: The UFO Study (Unexplained Falls in Older Patients).

PubMed

Chiara, Mussi; Gianluigi, Galizia; Pasquale, Abete; Alessandro, Morrione; Alice, Maraviglia; Gabriele, Noro; Paolo, Cavagnaro; Loredana, Ghirelli; Giovanni, Tava; Franco, Rengo; Giulio, Masotti; Gianfranco, Salvioli; Niccolò, Marchionni; Andrea, Ungar

2013-01-01

To evaluate the incidence of unexplained falls in elderly patients affected by fall-related fractures admitted to orthopaedic wards, we recruited 246 consecutive patients older than 65 (mean age 82 ± 7 years, range 65-101). Falls were defined "accidental" (fall explained by a definite accidental cause), "medical" (fall caused directly by a specific medical disease), "dementia-related" (fall in patients affected by moderate-severe dementia), and "unexplained" (nonaccidental falls, not related to a clear medical or drug-induced cause or with no apparent cause). According to the anamnestic features of the event, older patients had a lower tendency to remember the fall. Patients with accidental fall remember more often the event. Unexplained falls were frequent in both groups of age. Accidental falls were more frequent in younger patients, while dementia-related falls were more common in the older ones. Patients with unexplained falls showed a higher number of depressive symptoms. In a multivariate analysis a higher GDS and syncopal spells were independent predictors of unexplained falls. In conclusion, more than one third of all falls in patients hospitalized in orthopaedic wards were unexplained, particularly in patients with depressive symptoms and syncopal spells. The identification of fall causes must be evaluated in older patients with a fall-related injury.

A smart rock

NASA Astrophysics Data System (ADS)

Pressel, Phil

2014-12-01

This project was to design and build a protective weapon for a group of associations that believed in aliens and UFO's. They collected enough contributions from societies and individuals to be able to sponsor and totally fund the design, fabrication and testing of this equipment. The location of this facility is classified. It also eventually was redesigned by the Quartus Engineering Company for use at a major amusement park as a "shoot at targets facility." The challenge of this project was to design a "smart rock," namely an infrared bullet (the size of a gallon can of paint) that could be shot from the ground to intercept a UFO or any incoming suspicious item heading towards the earth. Some of the challenges to design this weapon were to feed cryogenic helium at 5 degrees Kelvin from an inair environment through a unique rotary coupling and air-vacuum seal while spinning the bullet at 1500 rpm and maintain its dynamic stability (wobble) about its spin axis to less than 10 micro-radians (2 arc seconds) while it operated in a vacuum. Precision optics monitored the dynamic motion of the "smart rock."

Insights on surface spalling of rock

NASA Astrophysics Data System (ADS)

Tarokh, Ali; Kao, Chu-Shu; Fakhimi, Ali; Labuz, Joseph F.

2016-07-01

Surface spalling is a complex failure phenomenon that features crack propagation and detachment of thin pieces of rock near free surfaces, particularly in brittle rock around underground excavations when large in situ stresses are involved. A surface instability apparatus was used to study failure of rock close to a free surface, and damage evolution was monitored by digital image correlation (DIC). Lateral displacement at the free face was used as the feedback signal to control the post-peak response of the specimen. DIC was implemented in order to obtain the incremental displacement fields during the spalling process. Displacement fields were computed in the early stage of loading as well as close to the peak stress. Fracture from the spalling phenomenon was revealed by incremental lateral displacement contours. The axial and lateral displacements suggested that the displacement gradient was uniform in both directions at early loading stages and as the load increased, the free-face effect started to influence the displacements, especially the lateral displacement field. A numerical approach, based on the discrete element method, was developed and validated from element testing. Damage evolution and localization observed in numerical simulations were similar to those observed in experiments. By performing simulations in two- and three-dimensions, it was revealed that the intermediate principal stress and platen-rock interfaces have important effects on simulation of surface spalling.

Review of Studies of Mechanoelectrical Transformations in Rocks in Russia and Abroad

NASA Astrophysics Data System (ADS)

Pomishin, E.; Yavorovich, L.

2016-06-01

The problem of monitoring and forecast of dynamic manifestations of rock masses becomes immediate in the mining industry because of the growth of mining work intensity and changeover to the mining operations in deeper levels. The article presents a short review of the scientific works of foreign researchers for more complete and in-depth study of geophysical methods of control of the stress-strain state and bump hazard of rock masses.

Estimating the Wet-Rock P-Wave Velocity from the Dry-Rock P-Wave Velocity for Pyroclastic Rocks

NASA Astrophysics Data System (ADS)

Kahraman, Sair; Fener, Mustafa; Kilic, Cumhur Ozcan

2017-07-01

Seismic methods are widely used for the geotechnical investigations in volcanic areas or for the determination of the engineering properties of pyroclastic rocks in laboratory. Therefore, developing a relation between the wet- and dry-rock P-wave velocities will be helpful for engineers when evaluating the formation characteristics of pyroclastic rocks. To investigate the predictability of the wet-rock P-wave velocity from the dry-rock P-wave velocity for pyroclastic rocks P-wave velocity measurements were conducted on 27 different pyroclastic rocks. In addition, dry-rock S-wave velocity measurements were conducted. The test results were modeled using Gassmann's and Wood's theories and it was seen that estimates for saturated P-wave velocity from the theories fit well measured data. For samples having values of less and greater than 20%, practical equations were derived for reliably estimating wet-rock P-wave velocity as function of dry-rock P-wave velocity.

REFINE (Reducing Falls in In-patient Elderly)--a randomised controlled trial.

PubMed

Vass, Catherine D; Sahota, Opinder; Drummond, Avril; Kendrick, Denise; Gladman, John; Sach, Tracey; Avis, Mark; Grainge, Matthew

2009-09-10

Falls in hospitals are common, resulting in injury and anxiety to patients, and large costs to NHS organisations. More than half of all in-patient falls in elderly people in acute care settings occur at the bedside, during transfers or whilst getting up to go to the toilet. In the majority of cases these falls are unwitnessed. There is insufficient evidence underpinning the effectiveness of interventions to guide clinical staff regarding the reduction of falls in the elderly inpatient. New patient monitoring technologies have the potential to offer advances in falls prevention. Bedside sensor equipment can alert staff, not in the immediate vicinity, to a potential problem and avert a fall. However no studies utilizing this assistive technology have demonstrated a significant reduction in falls rates in a randomised controlled trial setting. The research design is an individual patient randomised controlled trial of bedside chair and bed pressure sensors, incorporating a radio-paging alerting mode to alert staff to patients rising from their bed or chair, across five acute elderly care wards in Nottingham University Hospitals NHS Trust. Participants will be randomised to bedside chair and bed sensors or to usual care (without the use of sensors). The primary outcome is the number of bedside in-patient falls. The REFINE study is the first randomised controlled trial of bedside pressure sensors in elderly inpatients in an acute NHS Trust. We will assess whether falls can be successfully and cost effectively reduced using this technology, and report on its acceptability to both patients and staff.

Rocks.

ERIC Educational Resources Information Center

Lee, Alice

This science unit is designed for limited- and non-English speaking students in a Chinese bilingual education program. The unit covers rock material, classification, characteristics of types of rocks, and rock cycles. It is written in Chinese and simple English. At the end of the unit there is a list of main terms in both English and Chinese, and…

Falls in spinocerebellar ataxias: Results of the EuroSCA Fall Study.

PubMed

Fonteyn, Ella M R; Schmitz-Hübsch, Tanja; Verstappen, Carla C; Baliko, Laslo; Bloem, Bastiaan R; Boesch, Silvia; Bunn, Lisa; Charles, Perrine; Dürr, Alexandra; Filla, Allesandro; Giunti, Paola; Globas, Christoph; Klockgether, Thomas; Melegh, Bela; Pandolfo, Massimo; De Rosa, Anna; Schöls, Ludger; Timmann, Dagmar; Munneke, Marten; Kremer, Berry P H; van de Warrenburg, Bart P C

2010-06-01

To investigate the frequency, details, and consequences of falls in patients with autosomal dominant spinocerebellar ataxias (SCAs) and to derive specific disease-related risk factors that are associated with an increased fall frequency. Two hundred twenty-eight patients with SCA1, SCA2, SCA3, or SCA6, recruited from the EuroSCA natural history study, completed a fall questionnaire that assessed the frequency, consequences, and several details of falls in the previous 12 months. Relevant disease characteristics were retrieved from the EuroSCA registry. The database of the natural history study provided the ataxia severity scores as well as the number and nature of non-ataxia symptoms. Patients (73.6%) reported at least one fall in the preceding 12 months. There was a high rate of fall-related injuries (74%). Factors that were associated with a higher fall frequency included: disease duration, severity of ataxia, the presence of pyramidal symptoms, the total number of non-ataxia symptoms, and the genotype SCA3. Factors associated with a lower fall frequency were: the presence of extrapyramidal symptoms (more specifically dystonia of the lower limbs) and the genotype SCA2. The total number of non-ataxia symptoms and longer disease duration were independently associated with a higher fall frequency in a logistic regression analysis, while the presence of extrapyramidal symptoms was independently associated with a lower fall frequency. Our findings indicate that, in addition to more obvious factors that are associated with frequent falls, such as disease duration and ataxia severity, non-ataxia manifestations in SCA play a major role in the fall etiology of these patients.

In Situ Observation of Hard Surrounding Rock Displacement at 2400-m-Deep Tunnels

NASA Astrophysics Data System (ADS)

Feng, Xia-Ting; Yao, Zhi-Bin; Li, Shao-Jun; Wu, Shi-Yong; Yang, Cheng-Xiang; Guo, Hao-Sen; Zhong, Shan

2018-03-01

This paper presents the results of in situ investigation of the internal displacement of hard surrounding rock masses within deep tunnels at China's Jinping Underground Laboratory Phase II. The displacement evolution of the surrounding rock during the entire excavation processes was monitored continuously using pre-installed continuous-recording multi-point extensometers. The evolution of excavation-damaged zones and fractures in rock masses were also observed using acoustic velocity testing and digital borehole cameras, respectively. The results show four kinds of displacement behaviours of the hard surrounding rock masses during the excavation process. The displacement in the inner region of the surrounding rock was found to be greater than that of the rock masses near the tunnel's side walls in some excavation stages. This leads to a multi-modal distribution characteristic of internal displacement for hard surrounding rock masses within deep tunnels. A further analysis of the evolution information on the damages and fractures inside the surrounding rock masses reveals the effects of excavation disturbances and local geological conditions. This recognition can be used as the reference for excavation and supporting design and stability evaluations of hard-rock tunnels under high-stress conditions.

Putting Adaptive Management into Monitoring: Retrospective and Prospective Views of Northwest Forest Plan Monitoring

Treesearch

David E. Busch; Jon R. Martin

2006-01-01

Based on ten years of Northwest Forest Plan implementation, we focus on key scientifically-oriented questions relating to improving Plan monitoring. The questions, which fall into groups concerning issues of scale, integration, and efficiency, have applicability to monitoring programs being designed and implemented throughout the world. Progress toward answering such...

Application of underground microseismic monitoring for ground failure and secure longwall coal mining operation: A case study in an Indian mine

NASA Astrophysics Data System (ADS)

Ghosh, G. K.; Sivakumar, C.

2018-03-01

Longwall mining technique has been widely used around the globe due to its safe mining process. However, mining operations are suspended when various problems arise like collapse of roof falls, cracks and fractures propagation in the roof and complexity in roof strata behaviors. To overcome these colossal problems, an underground real time microseismic monitoring technique has been implemented in the working panel-P2 in the Rajendra longwall underground coal mine at South Eastern Coalfields Limited (SECL), India. The target coal seams appears at the panel P-2 within a depth of 70 m to 76 m. In this process, 10 to 15 uniaxial geophones were placed inside a borehole at depth range of 40 m to 60 m located over the working panel-P2 with high rock quality designation value for better seismic signal. Various microseismic events were recorded with magnitude ranging from -5 to 2 in the Richter scale. The time-series processing was carried out to get various seismic parameters like activity rate, potential energy, viscosity rate, seismic moment, energy index, apparent volume and potential energy with respect to time. The used of these parameters helped tracing the events, understanding crack and fractures propagation and locating both high and low stress distribution zones prior to roof fall occurrence. In most of the cases, the events were divided into three stage processes: initial or preliminary, middle or building, and final or falling. The results of this study reveal that underground microseismic monitoring provides sufficient prior information of underground weighting events. The information gathered during the study was conveyed to the mining personnel in advance prior to roof fall event. This permits to take appropriate action for safer mining operations and risk reduction during longwall operation.

Impact of Fall Prevention on Nurses and Care of Fall Risk Patients.

PubMed

King, Barbara; Pecanac, Kristen; Krupp, Anna; Liebzeit, Daniel; Mahoney, Jane

2018-03-19

Falls are common events for hospitalized older adults, resulting in negative outcomes both for patients and hospitals. The Center for Medicare and Medicaid (CMS) has placed pressure on hospital administrators by identifying falls as a "never event", resulting in a zero falls goal for many hospitals. Staff nurses are responsible for providing direct care to patients and for meeting the hospital no falls goal. Little is known about the impact of "zero falls" on nurses, patients and the organization. A qualitative study, using Grounded Dimensional Analysis (GDA) was conducted to explore nurses' experiences with fall prevention in hospital settings and the impact of those experiences on how nurses provide care to fall risk patients. Twenty-seven registered nurses and certified nursing assistants participated in in-depth interviews. Open, axial and selective coding was used to analyze data. A conceptual model which illustrates the impact of intense messaging from nursing administration to prevent patient falls on nurses, actions nurses take to address the message and the consequences to nurses, older adult patients and to the organization was developed. Intense messaging from hospital administration to achieve zero falls resulted in nurses developing a fear of falls, protecting self and unit, and restricting fall risk patients as a way to stop messages and meet the hospital goal. Results of this study identify unintended consequences of fall prevention message on nurses and older adult patients. Further research is needed understand how nurse care for fall risk patients.

Effect of a Multidisciplinary Fall Risk Assessment on Falls Among Neurology Inpatients

PubMed Central

Hunderfund, Andrea N. Leep; Sweeney, Cynthia M.; Mandrekar, Jayawant N.; Johnson, LeAnn M.; Britton, Jeffrey W.

2011-01-01

OBJECTIVE: To evaluate whether the addition of a physician assessment of patient fall risk at admission would reduce inpatient falls on a tertiary hospital neurology inpatient unit. PATIENTS AND METHODS: A physician fall risk assessment was added to the existing risk assessment process (clinical nurse evaluation and Hendrich II Fall Risk Model score with specific fall prevention measures for patients at risk). An order to select either “Patient is” or “Patient is not at high risk of falls by physician assessment” was added to the physician electronic admission order set. Nurses and physicians were instructed to reach consensus when assessments differed. Full implementation occurred in second-quarter 2008. Preimplementation (January 1, 2006, to March 31, 2008) and postimplementation (April 1, 2008, to December 31, 2009) rates of falls were compared on the neurology inpatient unit and on 6 other medical units that did not receive intervention. RESULTS: The rate of falls during the 7 quarters after full implementation was significantly lower than that during the 9 preceding quarters (4.12 vs 5.69 falls per 1000 patient-days; P=.04), whereas the rate of falls on other medical units did not significantly change (2.99 vs 3.33 falls per 1000 patient-days; P=.24, Poisson test). The consensus risk assessment at admission correctly identified patients at risk for falls (14/325 at-risk patients fell vs 0/147 low-risk patients; P=.01, χ2 test), but the Hendrich II Fall Risk Model score, nurse, and physician assessments individually did not. CONCLUSION: A multidisciplinary approach to fall risk assessment is feasible, correctly identifies patients at risk, and was associated with a reduction in inpatient falls. PMID:21193651

Imaging and computational considerations for image computed permeability: Operating envelope of Digital Rock Physics

NASA Astrophysics Data System (ADS)

Saxena, Nishank; Hows, Amie; Hofmann, Ronny; Alpak, Faruk O.; Freeman, Justin; Hunter, Sander; Appel, Matthias

2018-06-01

This study defines the optimal operating envelope of the Digital Rock technology from the perspective of imaging and numerical simulations of transport properties. Imaging larger volumes of rocks for Digital Rock Physics (DRP) analysis improves the chances of achieving a Representative Elementary Volume (REV) at which flow-based simulations (1) do not vary with change in rock volume, and (2) is insensitive to the choice of boundary conditions. However, this often comes at the expense of image resolution. This trade-off exists due to the finiteness of current state-of-the-art imaging detectors. Imaging and analyzing digital rocks that sample the REV and still sufficiently resolve pore throats is critical to ensure simulation quality and robustness of rock property trends for further analysis. We find that at least 10 voxels are needed to sufficiently resolve pore throats for single phase fluid flow simulations. If this condition is not met, additional analyses and corrections may allow for meaningful comparisons between simulation results and laboratory measurements of permeability, but some cases may fall outside the current technical feasibility of DRP. On the other hand, we find that the ratio of field of view and effective grain size provides a reliable measure of the REV for siliciclastic rocks. If this ratio is greater than 5, the coefficient of variation for single-phase permeability simulations drops below 15%. These imaging considerations are crucial when comparing digitally computed rock flow properties with those measured in the laboratory. We find that the current imaging methods are sufficient to achieve both REV (with respect to numerical boundary conditions) and required image resolution to perform digital core analysis for coarse to fine-grained sandstones.

Monitoring and Evaluation of Yearling Fall Chinook Salmon (Oncorhynchus tshawytscha) Released from Acclimation Facilities Upstream of Lower Granite Dam; 1999 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rocklage, Stephen J.; Kellar, Dale S.

2005-07-01

The Nez Perce Tribe, in cooperation with the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife, conducted monitoring and evaluation studies on Lyons Ferry Hatchery reared yearling fall Chinook salmon Oncorhynchus tshawytscha that were acclimated and released at three Fall Chinook Acclimation Project (FCAP) sites upstream of Lower Granite Dam along with yearlings released on-station from Lyons Ferry Hatchery in 1999. This was the fourth year of a long-term project to supplement natural spawning populations of Snake River stock fall Chinook salmon upstream of Lower Granite Dam. The 453,117 yearlings released from the Fall Chinook Acclimationmore » Project facilities not only slightly exceeded the 450,000 fish quota, but a second release of 76,386 yearlings (hereafter called Surplus) were acclimated at the Big Canyon facility and released about two weeks after the primary releases. We use Passive Integrated Transponder (PIT) tag technology to monitor the primary performance measures of survival to mainstem dams and migration timing. We also monitor size, condition and tag/mark retention at release. We released 9,941 PIT tagged yearlings from Pittsburg Landing, 9,583 from Big Canyon, 2,511 Big Canyon Surplus and 2,494 from Captain John Rapids. The Washington Department of Fish and Wildlife released 983 PIT tagged yearlings from Lyons Ferry Hatchery. Fish health sampling indicated that, overall, bacterial kidney disease levels could be considered relatively low and did not appear to increase after transport to the acclimation facilities. Compared to prior years, Quantitative Health Assessment Indices were relatively low at Pittsburg Landing and Lyons Ferry Hatchery and relatively high at Big Canyon and Captain John Rapids. Mean fork lengths (95% confidence interval) of the release groups ranged from 147.4 mm (146.7-148.1 mm) at Captain John Rapids to 163.7 mm (163.3-164.1 mm) at Pittsburg Landing. Mean condition factors ranged from 1.04 at

Unravelling the magmatic processes behind zoned fall units on Ascension Island, South Atlantic

NASA Astrophysics Data System (ADS)

Chamberlain, K. J.; Barclay, J.; Preece, K.; Brown, R. J.; Davidson, J.

2015-12-01

Ascension Island, an isolated composite volcano in the south Atlantic, has a wide spectrum of explosive and effusive deposits. Eruptions on the island have produced ash and pumice fall deposits, ignimbrites, scoria cones, lava flows and lava domes, which vary in composition from basalt to rhyolite. We report, for the first time, the presence of multiple, zoned pumice fall deposits. These deposits grade upwards (stepwise or gradationally) from pumice to scoria. We present detailed observations of two key deposits which typify the range in zonation observed in the unusual fall units. Forensic examination of these deposits and their petrological and geochemical characteristics provide critical information about the interactions and processes behind the wide spectrum of magma compositions and past eruptive behaviour on Ascension Island. The first deposit changes gradationally from fayalite-bearing trachytic pumice fall (61.1 wt.% SiO2) at the base, to basaltic trachy-andesite scoria fall (54.5 wt.% SiO2) at the top. The second deposit is more complex. It contains mingled pumice-scoria clasts, has a rapid transition from pumice to scoria and no intermediate clasts were observed. New analyses of H2O, CO2 and key trace elements within melt inclusions combined with systematic whole rock and phenocryst analyses enable us to probe the relationship of these co-erupted magmas to other deposits on the island. This has yielded insights into the magma plumbing system; and improved understanding of the roles that fractional crystallisation and magma mixing play in generating the range in compositions observed at this unique ocean island volcano.

Measuring and mapping rock wall permafrost across Norway

NASA Astrophysics Data System (ADS)

Magnin, Florence; Etzelmuller, Bernd; Hilger, Paula; Westermann, Sebastian; Isaksen, Ketil; Hermans, Reginald

2017-04-01

The investigation of rock wall permafrost is of high relevance for geohazards assessment and for understanding cold-climate landscape evolution since its changes over time can cause slope instability and trigger rock falls. The destabilization of steep slopes is a serious threat to human activities and lives in Norway, especially because most of rock walls lie directly above houses, infrastructures and large water bodies with potential of high-energy displacement waves. Rock wall permafrost has been investigated since the early 2010s in alpine massifs of western Norway thanks to the CryoLINK project (2008-2011). The CryoWALL project (2015-2019) aims at extending this preliminary study to the nation-wide scale. It consists in systematic measurements of rock surface temperature (RST) in order model and to map the spatial distribution of rock wall permafrost. In between August 2015 and August 2016, 20 RST loggers (Geoprecision mini data loggers, accuracy ± 0.1°C, precision 0.01°C, sensors PT1000) were installed at 10 cm depth of 7 selected sites. These loggers are distributed along a latitudinal transect (from 60°50'N to 69°46'N), cover various elevations and sun-exposures, and are completed by 4 other loggers installed in Jotunheimen in 2009 and 2010. The RST time series are used for (a) characterizing the distribution of rock wall permafrost across Norway, (b) running steady-state and transient numerical models of rock wall permafrost at selected sites, and to (c) calibrate a general linear regression model that will be used to (d) predict the spatial distribution of rock wall permafrost at the national scale. In this communication we will introduce the RST measurement installations and sites, as well as the first RST records that encompass 6 years of continuous measurements in Jotunheimen, and 1 year of record for 13 other loggers. The preliminary analysis shows that RST differs by 3°C between N and S faces in Southern Norway, with mean annual RST as low as

The design of a purpose-built exergame for fall prediction and prevention for older people.

PubMed

Marston, Hannah R; Woodbury, Ashley; Gschwind, Yves J; Kroll, Michael; Fink, Denis; Eichberg, Sabine; Kreiner, Karl; Ejupi, Andreas; Annegarn, Janneke; de Rosario, Helios; Wienholtz, Arno; Wieching, Rainer; Delbaere, Kim

2015-01-01

Falls in older people represent a major age-related health challenge facing our society. Novel methods for delivery of falls prevention programs are required to increase effectiveness and adherence to these programs while containing costs. The primary aim of the Information and Communications Technology-based System to Predict and Prevent Falls (iStoppFalls) project was to develop innovative home-based technologies for continuous monitoring and exercise-based prevention of falls in community-dwelling older people. The aim of this paper is to describe the components of the iStoppFalls system. The system comprised of 1) a TV, 2) a PC, 3) the Microsoft Kinect, 4) a wearable sensor and 5) an assessment and training software as the main components. The iStoppFalls system implements existing technologies to deliver a tailored home-based exercise and education program aimed at reducing fall risk in older people. A risk assessment tool was designed to identify fall risk factors. The content and progression rules of the iStoppFalls exergames were developed from evidence-based fall prevention interventions targeting muscle strength and balance in older people. The iStoppFalls fall prevention program, used in conjunction with the multifactorial fall risk assessment tool, aims to provide a comprehensive and individualised, yet novel fall risk assessment and prevention program that is feasible for widespread use to prevent falls and fall-related injuries. This work provides a new approach to engage older people in home-based exercise programs to complement or provide a potentially motivational alternative to traditional exercise to reduce the risk of falling.

Selective attentional processing to fall-relevant stimuli among older adults who fear falling.

PubMed

Brown, Lesley A; White, Patti; Doan, Jonathan B; de Bruin, Natalie

2011-05-01

Fear of falling is known to affect more than half of community-dwelling older adults over 60 years of age. This fear is associated with physical and psychological effects that increase the risk of falling. The authors' theory is that attentional processing biases may exist in this population that serve to perpetuate fear of falling and subsequently increase fall risk. As a starting point in testing this proposition, the authors examined selective attentional processing bias to fall-relevant stimuli among older adults. Thirty older adult participants (M(age) = 70.8 ± 5.8), self-categorized to be Fearful of Falling (FF, n = 15) or Non-Fearful of Falling (NF, n = 15) completed a visual dot-probe paradigm to determine detection latencies to fall-threatening and general-threat stimuli. Attentional processing was defined using three index scores: attentional bias, congruency index, and incongruency index. Bias indicates capture of attention, whereas congruency and incongruency imply vigilance and disengagement difficulty, respectively. Both groups showed an attentional bias to fall-threat words but those who were fearful of falling also showed an incongruency effect for fall-threat words. These findings confirm that selective attentional processing profiles for fall-relevant stimuli differ between older adults who exhibit fear of falling and those who do not have this fear. Moreover, in accordance with current interpretations of selective attentional processing, the incongruency effect noted among fall-fearful older adults presents a possibility for a difficulty disengaging from fall-threatening stimuli.

A new understanding of fluid-rock deformation

NASA Astrophysics Data System (ADS)

Crampin, Stuart; Gao, Yuan

2015-04-01

Cracks in the pavement show that rock is weak to shear stress. Consequently we have a conundrum. How does in situ rock accumulate the enormous shear-stress energy necessary for release by a large magnitude earthquake without fracturing in smaller earthquakes? For example: observations of changes in seismic shear-wave splitting (SWS) were observed in Iceland before the 2004 Mw9.2 Sumatra-Andaman Earthquake (SAE) at a distance of ~10,500km (the width of the Eurasian Plate) from Indonesia. Observations of SWS monitor microcrack geometry, and the changes in SWS in Iceland indicated that stress-changes before the Sumatra earthquake modified microcrack geometry the width of Eurasia from Indonesia. What is the mechanism for such widespread accumulation of necessarily weak stress? We show that stress is stored in in situ rock by the stress-controlled geometry of the fluid-saturated stress-aligned microcrack. Microcrack aspect-ratios are aligned by fluid flow or dispersion along pressure-gradients between neighbouring microcracks at different orientations to the stress-field by a mechanism known as Anisotropic Poro-Elasticity or APE. Since the minimum stress is typically horizontal, the microcracks are typically vertically-oriented parallel to the maximum horizontal stress as is confirmed by observations of SWS. Such azimuthally varying shear-wave splitting (SWS) is observed in situ rocks in the upper crust, lower crust, and uppermost ~400km of the mantle. (The 'microcracks' in the mantle are intergranular films of hydrolysed melt.) SWS shows that the microcracks are so closely spaced that they verge on fracturing/earthquakes. Phenomena verging on failure are critical-systems with 'butterfly wings' sensitivity. Critical-systems are very common and it must be expected that the Earth, an archetypal complex heterogeneous interactive phenomena is a critical-system. Monitoring SWS above small earthquakes allows stress-accumulation before earthquakes to be recognised and the time

Quantification of CO2-FLUID-ROCK Reactions Using Reactive and Non-Reactive Tracers

NASA Astrophysics Data System (ADS)

Matter, J.; Stute, M.; Hall, J. L.; Mesfin, K. G.; Gislason, S. R.; Oelkers, E. H.; Sigfússon, B.; Gunnarsson, I.; Aradottir, E. S.; Alfredsson, H. A.; Gunnlaugsson, E.; Broecker, W. S.

2013-12-01

Carbon dioxide mineralization via fluid-rock reactions provides the most effective and long-term storage option for geologic carbon storage. Injection of CO2 in geologic formations induces CO2 -fluid-rock reactions that may enhance or decrease the storage permanence and thus the long-term safety of geologic carbon storage. Hence, quantitative characterization of critical CO2 -fluid-rock interactions is essential to assess the storage efficiency and safety of geologic carbon storage. In an attempt to quantify in-situ fluid-rock reactions and CO2 transport relevant for geologic carbon storage, we are testing reactive (14C, 13C) and non-reactive (sodium fluorescein, amidorhodamine G, SF5CF3, and SF6) tracers in an ongoing CO2 injection in a basaltic storage reservoir at the CARBFIX pilot injection site in Iceland. At the injection site, CO2 is dissolved in groundwater and injected into a permeable basalt formation located 500-800 m below the surface [1]. The injected CO2 is labeled with 14C by dynamically adding calibrated amounts of H14CO3-solution into the injection stream in addition to the non-reactive tracers. Chemical and isotopic analyses of fluid samples collected in a monitoring well, reveal fast fluid-rock reactions. Maximum SF6 concentration in the monitoring well indicates the bulk arrival of the injected CO2 solution but dissolved inorganic carbon (DIC) concentration and pH values close to background, and a potentially lower 14C to SF6 ratio than the injection ratio suggest that most of the injected CO2 has reacted with the basaltic rocks. This is supported by δ13CDIC, which shows a drop from values close to the δ 13C of the injected CO2 gas (-3‰ VPDB) during breakthrough of the CO2 plume to subsequent more depleted values (-11.25‰ VPDB), indicating precipitation of carbonate minerals. Preliminary mass balance calculations using mixing relationships between the background water in the storage formation and the injected solution, suggest that

Experimental research on the electromagnetic radiation (EMR) characteristics of cracked rock.

PubMed

Song, Xiaoyan; Li, Xuelong; Li, Zhonghui; Cheng, Fuqi; Zhang, Zhibo; Niu, Yue

2018-03-01

Coal rock would emit the electromagnetic radiation (EMR) while deformation and fracture, and there exists structural body in the coal rock because of mining and geological structure. In this paper, we conducted an experimental test the EMR characteristics of cracked rock under loading. Results show that crack appears firstly in the prefabricated crack tip then grows stably parallel to the maximum principal stress, and the coal rock buckling failure is caused by the wing crack tension. Besides, the compressive strength significantly decreases because of the precrack, and the compressive strength increases with the crack angle. Intact rock EMR increases with the loading, and the cracked rock EMR shows stage and fluctuant characteristics. The bigger the angle, the more obvious the stage and fluctuant characteristics, that is EMR becomes richer. While the cracked angle is little, EMR is mainly caused by the electric charge rapid separates because of friction sliding. While the cracked angle is big, there is another significant contribution to EMR, which is caused by the electric dipole transient of crack expansion. Through this, we can know more clear about the crack extends route and the corresponding influence on the EMR characteristic and mechanism, which has important theoretical and practical significance to monitor the coal rock dynamical disasters.

Wearable vital parameters monitoring system

NASA Astrophysics Data System (ADS)

Caramaliu, Radu Vadim; Vasile, Alexandru; Bacis, Irina

2015-02-01

The system we propose monitors body temperature, heart rate and beside this, it tracks if the person who wears it suffers a faint. It uses a digital temperature sensor, a pulse sensor and a gravitational acceleration sensor to monitor the eventual faint or small heights free falls. The system continuously tracks the GPS position when available and stores the last valid data. So, when measuring abnormal vital parameters the module will send an SMS, using the GSM cellular network , with the person's social security number, the last valid GPS position for that person, the heart rate, the body temperature and, where applicable, a valid fall alert or non-valid fall alert. Even though such systems exist, they contain only faint detection or heart rate detection. Usually there is a strong correlation between low/high heart rate and an eventual faint. Combining both features into one system results in a more reliable detection device.

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: STRESS SHEET, SHEET 4; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

Stratigraphy, geochemistry and tectonic significance of the Oligocene magmatic rocks of western Oaxaca, southern Mexico

USGS Publications Warehouse

Martiny, B.; Martinez-Serrano, R. G.; Moran-Zenteno, D. J.; MacIas-Romo, C.; Ayuso, R.A.

2000-01-01

In Western Oaxaca, Tertiary magmatic activity is represented by extensive plutons along the continental margin and volcanic sequences in the inland region. K-Ar age determinations reported previously and in the present work indicate that these rocks correspond to a relatively broad arc in this region that was active mainly during the Oligocene (~ 35 to ~ 25 Ma). In the northern sector of western Oaxaca (Huajuapan-Monte Verde-Yanhuitlan), the volcanic suite comprises principally basaltic andesite to andesitic lavas, overlying minor silicic to intermediate volcaniclastic rocks (epiclastic deposits, ash fall tuffs, ignimbrites) that were deposited in the lacustrine-fluvial environment. The southern sector of the volcanic zone includes the Tlaxiaco-Laguna de Guadalupe region and consists of intermediate to silicic pyroclastic and epiclastic deposits, with silicic ash fall tuffs and ignimbrites. In both sectors, numerous andesitic to dacitic hypabyssal intrusions (stocks and dikes) were emplaced at different levels of the sequence. The granitoids of the coastal plutonic belt are generally more differentiated than the volcanic rocks that predominate in the northern sector and vary in composition from granite to granodiorite. The studied rocks show large-ion lithophile element (LILE) enrichment (K, Rb, Ba, Th) relative to high-field-strength (HFS) elements (Nb, Ti, Zr) that is characteristic of subduction-related magmatic rocks. On chondrite-normalized rare earth element diagrams, these samples display light rare earth element enrichment (LREE) and a flat pattern for the heavy rare earth elements (HREE). In spite of the contrasting degree of differentiation between the coastal plutons and inland volcanic rocks, there is a relatively small variation in the isotopic composition of these two suites. Initial 87Sr/86Sr ratios obtained and reported previously for Tertiary plutonic rocks of western Oaxaca range from 0.7042 to 0.7054 and ??Nd values, from -3.0 to +2.4, and for

The Association Between Fall Frequency, Injury Risk, and Characteristics of Falls in Older Residents of Long-Term Care: Do Recurrent Fallers Fall More Safely?

PubMed

van Schooten, Kimberley S; Yang, Yijian; Feldman, Fabio; Leung, Ming; McKay, Heather; Sims-Gould, Joanie; Robinovitch, Stephen N

2018-05-09

Although a fall is a necessary prerequisite to a fall-related injury, previous studies suggest that frequent fallers are at lower injury risk for a given fall. We tested the hypotheses that differences in protective responses or the circumstances of falls underlie differences in injury risk with fall frequency. We analyzed video footage of 897 falls experienced by 220 long-term care residents (mean age 82 ± 9 years) to identify the cause of imbalance, activity leading to falling, direction of fall initiation, balance recovery and fall protective responses, and occurrence of impact to the head or hip. We further obtained injury information from the facilities' fall registration. We used generalized estimating equation models to examine the association between quartiles of fall frequency, injury risk, and fall characteristics. Residents with the highest fall frequency group (Q4; ≥5.6 falls/year) were less likely to sustain an injury per fall. They were less likely to fall during walking and more likely to fall during stand-to-sit transfers. Residents in the lowest fall frequency group (Q1; <1.15 falls/year) were more likely to fall during walking, and walking was associated with an increased risk for injury. When compared to less frequent fallers, more frequent fallers had a lower risk for injury per fall. This appeared to be explained by differences in the circumstances of falls, and not by protective responses. Injury prevention strategies in long-term care should target both frequent and infrequent fallers, as the latter are more mobile and apt to sustain injury.

Elastic Rock Heterogeneity Controls Brittle Rock Failure during Hydraulic Fracturing

NASA Astrophysics Data System (ADS)

Langenbruch, C.; Shapiro, S. A.

2014-12-01

For interpretation and inversion of microseismic data it is important to understand, which properties of the reservoir rock control the occurrence probability of brittle rock failure and associated seismicity during hydraulic stimulation. This is especially important, when inverting for key properties like permeability and fracture conductivity. Although it became accepted that seismic events are triggered by fluid flow and the resulting perturbation of the stress field in the reservoir rock, the magnitude of stress perturbations, capable of triggering failure in rocks, can be highly variable. The controlling physical mechanism of this variability is still under discussion. We compare the occurrence of microseismic events at the Cotton Valley gas field to elastic rock heterogeneity, obtained from measurements along the treatment wells. The heterogeneity is characterized by scale invariant fluctuations of elastic properties. We observe that the elastic heterogeneity of the rock formation controls the occurrence of brittle failure. In particular, we find that the density of events is increasing with the Brittleness Index (BI) of the rock, which is defined as a combination of Young's modulus and Poisson's ratio. We evaluate the physical meaning of the BI. By applying geomechanical investigations we characterize the influence of fluctuating elastic properties in rocks on the probability of brittle rock failure. Our analysis is based on the computation of stress fluctuations caused by elastic heterogeneity of rocks. We find that elastic rock heterogeneity causes stress fluctuations of significant magnitude. Moreover, the stress changes necessary to open and reactivate fractures in rocks are strongly related to fluctuations of elastic moduli. Our analysis gives a physical explanation to the observed relation between elastic heterogeneity of the rock formation and the occurrence of brittle failure during hydraulic reservoir stimulations. A crucial factor for understanding

Rock.XML - Towards a library of rock physics models

NASA Astrophysics Data System (ADS)

Jensen, Erling Hugo; Hauge, Ragnar; Ulvmoen, Marit; Johansen, Tor Arne; Drottning, Åsmund

2016-08-01

Rock physics modelling provides tools for correlating physical properties of rocks and their constituents to the geophysical observations we measure on a larger scale. Many different theoretical and empirical models exist, to cover the range of different types of rocks. However, upon reviewing these, we see that they are all built around a few main concepts. Based on this observation, we propose a format for digitally storing the specifications for rock physics models which we have named Rock.XML. It does not only contain data about the various constituents, but also the theories and how they are used to combine these building blocks to make a representative model for a particular rock. The format is based on the Extensible Markup Language XML, making it flexible enough to handle complex models as well as scalable towards extending it with new theories and models. This technology has great advantages as far as documenting and exchanging models in an unambiguous way between people and between software. Rock.XML can become a platform for creating a library of rock physics models; making them more accessible to everyone.

Fall Risk, Supports and Services, and Falls Following a Nursing Home Discharge.

PubMed

Noureldin, Marwa; Hass, Zachary; Abrahamson, Kathleen; Arling, Greg

2017-09-04

Falls are a major source of morbidity and mortality among older adults; however, little is known regarding fall occurrence during a nursing home (NH) to community transition. This study sought to examine whether the presence of supports and services impacts the relationship between fall-related risk factors and fall occurrence post NH discharge. Participants in the Minnesota Return to Community Initiative who were assisted in achieving a community discharge (N = 1459) comprised the study sample. The main outcome was fall occurrence within 30 days of discharge. Factor analyses were used to estimate latent models from variables of interest. A structural equation model (SEM) was estimated to determine the relationship between the emerging latent variables and falls. Fifteen percent of participants fell within 30 days of NH discharge. Factor analysis of fall-related risk factors produced three latent variables: fall concerns/history; activities of daily living impairments; and use of high-risk medications. A supports/services latent variable also emerged that included caregiver support frequency, medication management assistance, durable medical equipment use, discharge location, and receipt of home health or skilled nursing services. In the SEM model, high-risk medications use and fall concerns/history had direct positive effects on falling. Receiving supports/services did not affect falling directly; however, it reduced the effect of high-risk medication use on falling (p < .05). Within the context of a state-implemented transition program, findings highlight the importance of supports/services in mitigating against medication-related risk of falling post NH discharge. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fear of Falling Is Associated with Recurrent Falls in People with Multiple Sclerosis

PubMed Central

Lambert, William E.; Nguyen, Thuan; Bourdette, Dennis N.; Cameron, Michelle H.

2015-01-01

Background: People with multiple sclerosis (MS) fall frequently, and there are few clinically valid tools to measure the risk factors for falls. We assessed the unidimensionality of the 7-item Falls Efficacy Scale–International (FES-I), a measure of fear of falling, and determined whether the 7-item FES-I is associated with recurrent falls in people with MS. Methods: Falls were counted prospectively for 6 months using fall calendars in 58 people with MS (age, 18–50 years; Expanded Disability Status Scale score, 0–6). The FES-I was administered at baseline, and its unidimensionality was assessed by confirmatory factor analysis. The relationship between FES-I score and future falls, after adjusting for recurrent falls in the past year, was assessed by logistic regression. Results: Fifty-four participants who completed all assessments were included in the analysis. Goodness-of-fit indices confirmed a single-factor solution for the 7-item FES-I (discrepancy χ2, P = .101; Tucker-Lewis index, 0.953; comparative fit index, 0.969; root mean square error of approximation, 0.098). There was a significant association between fear of falling and falls in the following 3 months, independent of recurrent falls in the past year (odds ratio = 1.22, 95% confidence interval, 1.04–1.43, P = .016). Conclusions: The 7-item FES-I demonstrates good construct validity, allowing the total score to be used as a measure of fear of falling in people with MS. Fear of falling, as measured by the 7-item FES-I, is associated with future recurrent falls independent of past recurrent falls in people with MS. PMID:26300702

Exploring Older Adult ED Fall Patients' Understanding of Their Fall: A Qualitative Study.

PubMed

Shankar, Kalpana N; Taylor, Devon; Rizzo, Caroline T; Liu, Shan W

2017-12-01

We sought to understand older patients' perspectives about their fall, fall risk factors, and attitude toward emergency department (ED) fall-prevention interventions. We conducted semistructured interviews between July 2015 and January 2016 of community-dwelling, nondemented patients in the ED, who presented with a fall to an urban, teaching hospital. Interviews were halted once we achieve thematic saturation with the data coded and categorized into themes. Of the 63 patients interviewed, patients blamed falls on the environment, accidents, a medical condition, or themselves. Three major themes were generated: (1) patients blamed falls on a multitude of things but never acknowledged a possible multifactorial rationale, (2) patients have variable level of concerns regarding their current fall and future fall risk, and (3) patients demonstrated a range of receptiveness to ED interventions aimed at preventing falls but provided little input as to what those interventions should be. Many older patients who fall do not understand their fall risk. However, based on the responses provided, older adults tend to be more receptive to intervention and more concerned about their future fall risk, making the ED an appropriate setting for intervention.

A quantitative analysis of rock cliff erosion environments

NASA Astrophysics Data System (ADS)

Lim, M.; Rosser, N.; Petley, D. N.; Norman, E. C.; Barlow, J.

2009-12-01

The spatial patterns and temporal sequencing of failures from coastal rock cliffs are complex and typically generate weak correlations with environmental variables such as tidal inundation, wave energy, wind and rain. Consequently, understanding of rock cliff behaviour, its response to predicted changes in environmental forcing and, more specifically, the interaction between marine and climatic factors in influencing failure processes has remained limited. This work presents the results from the first attempt to characterise and quantify the conditions on coastal cliffs that lead to accelerated rates of material detachment. The rate of change in an 80 m high section of coastal rock cliffs has been surveyed annually with high-resolution terrestrial laser scanning (TLS). The rockfall data have been analysed according to a simplified source geology that exhibit distinct magnitude-frequency distributions relating to the dominance of particular failure types. An integrated network of sensors and instrumentation designed to reflect the lithological control on failure has been installed to examine both the distinction between prevailing conditions and those affecting the local cliff environment and the physical response of different rock types to micro-climatic processes. The monitoring system records near-surface rock strain, temperature, moisture and micro-seismic displacement in addition to air temperature, humidity, radiation, precipitation, water-level and three-dimensional wind characteristics. A characteristic environmental signal, unique to the cliff face material, has been identified that differs substantially from that experienced by the surrounding area; suggesting that established methods of meteorological and tidal data collection are insufficient and inappropriate to represent erosive processes. The interaction between thermo- and hydro-dynamics of the cliff environment and the physical response of the rock highlights the composite environmental effects

Fall TIPS: strategies to promote adoption and use of a fall prevention toolkit.

PubMed

Dykes, Patricia C; Carroll, Diane L; Hurley, Ann; Gersh-Zaremski, Ronna; Kennedy, Ann; Kurowski, Jan; Tierney, Kim; Benoit, Angela; Chang, Frank; Lipsitz, Stuart; Pang, Justine; Tsurkova, Ruslana; Zuyov, Lyubov; Middleton, Blackford

2009-11-14

Patient falls are serious problems in hospitals. Risk factors for falls are well understood and nurses routinely assess for fall risk on all hospitalized patients. However, the link from nursing assessment of fall risk, to identification and communication of tailored interventions to prevent falls is yet to be established. The Fall TIPS (Tailoring Interventions for Patient Safety) Toolkit was developed to leverage existing practices and workflows and to employ information technology to improve fall prevention practices. The purpose of this paper is to describe the Fall TIPS Toolkit and to report on strategies used to drive adoption of the Toolkit in four acute care hospitals. Using the IHI "Framework for Spread" as a conceptual model, the research team describes the "spread" of the Fall TIPS Toolkit as means to integrate effective fall prevention practices into the workflow of interdisciplinary caregivers, patients and family members.

Monitoring of waste disposal in deep geological formations

NASA Astrophysics Data System (ADS)

German, V.; Mansurov, V.

2003-04-01

In the paper application of kinetic approach for description of rock failure process and waste disposal microseismic monitoring is advanced. On base of two-stage model of failure process the capability of rock fracture is proved. The requests to monitoring system such as real time mode of data registration and processing and its precision range are formulated. The method of failure nuclei delineation in a rock masses is presented. This method is implemented in a software program for strong seismic events forecasting. It is based on direct use of the fracture concentration criterion. The method is applied to the database of microseismic events of the North Ural Bauxite Mine. The results of this application, such as: efficiency, stability, possibility of forecasting rockburst are discussed.

The role of rock moisture on regulating hydrologic and solute fluxes in the critical zone

NASA Astrophysics Data System (ADS)

Rempe, D. M.; Druhan, J. L.; Hahm, W. J.; Wang, J.; Murphy, C.; Cargill, S.; Dietrich, W. E.; Tune, A. K.

2017-12-01

In environments where the vadose zone extends below the soil layer into underlying weathered bedrock, the water held in the weathering -generated pores can be an important source of moisture to vegetation. The heterogeneous distribution of pore space in weathered bedrock, furthermore, controls the subsurface water flowpaths that dictate how water is partitioned in the critical zone (CZ) and evolves geochemically. Here, we present the results of direct monitoring of the fluxes of water and solutes through the deep CZ using a novel vadose zone monitoring system (VMS) as well as geophysical logging and sampling in a network of deep wells across a steep hillslope in Northern California. At our study site (Eel River CZO), multi-year monitoring reveals that a significant fraction of incoming rainfall (up to 30%) is seasonally stored in the fractures and matrix of the upper 12 m of weathered bedrock as rock moisture. Intensive geochemical and geophysical observations distributed from the surface to the depth of unweathered bedrock indicate that the seasonal addition and depletion of rock moisture has key implications for hydrologic and geochemical processes. First, rock moisture storage provides an annually consistent water storage reservoir for use by vegetation during the summer, which buffers transpiration fluxes against variability in seasonal precipitation. Second, because the timing and magnitude of groundwater recharge and streamflow are controlled by the annual filling and drainage of the rock moisture, rock moisture regulates the partitioning of hydrologic fluxes. Third, we find that rock moisture dynamics—which influence the myriad geochemical and microbial processes that weather bedrock—strongly correspond with the observed vertical weathering profile. As a result of the coupling between chemical weathering reactions and hydrologic fluxes, the geochemical composition of groundwater and streamflow is influenced by the temporal dynamics of rock moisture. Our

[Muscle and bone health as a risk factor of fall among the elderly. Fear of falling and the post-fall syndrome].

PubMed

Niino, Naoakira; Nishita, Yukiko

2008-06-01

Fear of falling and the post-fall syndrome (fear-related activity restriction) are serious psychological symptoms associated with falls. This paper reported the definition and prevalence of fear of falling. Prevalence has yielded highly varying estimates due to the various definitions and instruments used to measure fear. Correlates of fear of falling by a longitudinal study were also described. As most of the research on fear of falling has been cross-sectional, more longitudinal studies are needed. As to the post-fall syndrome, definition and prevalence among community-dwelling elderly was discussed. It is difficult to measure general prevalence due to the lack of solid criteria of this syndrome.

Medication use and fall-risk assessment for falls in an acute care hospital.

PubMed

Chiu, Ming-Huang; Lee, Hsin-Dai; Hwang, Hei-Fen; Wang, Shih-Chieh; Lin, Mau-Roung

2015-07-01

A nested case-control study was carried out to examine relationships of a fall-risk score and the use of single medications and polypharmacy with falls among hospitalized patients aged 50 years and older in Taiwan. There were 83 patients who experienced a fall during hospitalization in an acute-care hospital. Matched by age and sex, five control patients for each case were randomly selected from all other inpatients who had not experienced any fall at the time of the index fall. Patients who took tricyclic antidepressants, diuretics, and narcotics were 3.36-, 1.83- and 2.09-fold, respectively, more likely to experience a fall than their counterparts. Conversely, patients who took beta-blockers were 0.34-fold more likely than those who did not take them to experience a fall. Patients taking ≥6 medications were 3.08-fold more likely than those taking fewer medications to experience a fall, whereas those with anxiety were 4.72-fold more likely to experience a fall than those without. A high fall-risk score was not significantly associated with the occurrence of falls. Among older hospitalized patients, tricyclic antidepressants, diuretics, narcotics, and polypharmacy should be mindfully prescribed and reviewed on a regular basis. A fall-risk scale developed from community-dwelling older people might not accurately predict falls in hospitalized patients. Further research to validate the negative effect of beta-blocker use on falls is required. © 2014 Japan Geriatrics Society.

Falling and fall risk factors in adults with haemophilia: an exploratory study.

PubMed

Sammels, M; Vandesande, J; Vlaeyen, E; Peerlinck, K; Milisen, K

2014-11-01

Falls are a particular risk in persons with haemophilia (PWH) because of damaged joints, high risk of bleeding, possible impact on the musculoskeletal system and functioning and costs associated with treatment for these fall-related injuries. In addition, fall risk increases with age and PWH are increasingly entering the over 65 age group. The aim of this study was to determine the occurrence of falls during the past year and to explore which fall risk factors are present in community-dwelling PWH. Dutch speaking community-dwelling adults were included from the age of 40 years with severe or moderate haemophilia A or B, independent in their mobility and registered at the University Hospitals Leuven. They were asked to come to the haemophilia centre; otherwise a telephone survey was conducted. Demographic and social variables, medical variables, fall evaluation and clinical variables were queried. From the 89 PWH, 74 (83.1%) participated in the study. Twenty-four (32.4%) fell in the past year, and 10 of them (41.7%) more than once with an average of four falls. Living conditions, physical activity, avoidance of winter sports due to fear of falling, orthopaedic status, urinary incontinence and mobility impairments are potential fall risk factors in adult PWH. This exploratory study indicates that PWH are attentive to falling since they are at higher risk for falls and because of the serious consequences it might have. Screening and fall prevention should be stimulated in the daily practice of haemophilia care. © 2014 John Wiley & Sons Ltd.

Depression and Outcome of Fear of Falling in a Falls Prevention Program.

PubMed

Iaboni, Andrea; Banez, Carol; Lam, Robert; Jones, Simon A; Maki, Brian E; Liu, Barbara A; Flint, Alastair J

2015-10-01

To examine whether depression predicts less improvement in fear of falling and falls efficacy in older adults attending a falls prevention program (FPP). Using a prospective observational design in an academic medical center, the authors studied 69 nondemented adults aged 55 years or older (mean age: 77.8±8.9 years) who had experienced at least one fall in the previous year and who attended the FPP. The primary outcome variable was change in severity of fear of falling during the FPP. Secondary outcome variables were change in falls efficacy and fear-related restriction of activities during the FPP. Independent variables were baseline depressive disorders and depressive symptom severity. Twenty-one of 69 study participants (30.4%) had a depressive disorder at baseline. Depressive disorder and depressive symptoms were not associated with change in severity of fear of falling or restriction of activity. On the other hand, depressive disorder was associated with improvement in falls efficacy, although this finding was not significant in multivariate analysis. Among participants with a depressive disorder, improvement in falls efficacy was significantly correlated with improvement in depressive symptoms. There was no association between baseline depression and change in fear of falling in this FPP. The correlation between improvement in depressive symptoms and improvement in falls efficacy raises the question as to whether a cognitive-behavioral intervention that simultaneously targets both depression and falls efficacy would be a useful component of a FPP. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

"Rock Garden"

NASA Image and Video Library

1997-10-14

This false color composite image of the Rock Garden shows the rocks "Shark" and "Half Dome" at upper left and middle, respectively. Between these two large rocks is a smaller rock (about 0.20 m wide, 0.10 m high, and 6.33 m from the Lander) that was observed close-up with the Sojourner rover (see PIA00989). http://photojournal.jpl.nasa.gov/catalog/PIA00987

Which Fall Ascertainment Method Captures Most Falls in Pre-Frail and Frail Seniors?

PubMed

Teister, Corina J; Chocano-Bedoya, Patricia O; Orav, Endel J; Dawson-Hughes, Bess; Meyer, Ursina; Meyer, Otto W; Freystaetter, Gregor; Gagesch, Michael; Rizzoli, Rene; Egli, Andreas; Theiler, Robert; Kanis, John A; Bischoff-Ferrari, Heike A

2018-06-15

There is no consensus on most reliable falls ascertainment method. Therefore, we investigated which method captures most falls among pre-frail and frail seniors from two randomized controlled trials conducted in Zurich, Switzerland, a 18-month trial (2009-2010) including 200 community-dwelling pre-frail seniors with a prior fall and a 12-month trial (2005-2008) including 173 frail seniors with acute hip fracture. Both included the same fall ascertainment methods: monthly active-asking, daily self-report diary, and a call-in hotline. We compared number of falls reported and estimated overall and positive percent agreement between methods. Pre-frail seniors reported 499 falls (rate = 2.5/year) and frail seniors reported 205 falls (rate = 1.4/year). Most falls were reported by active-asking: 81% of falls in pre-frail, and 78% in frail seniors. Among pre-frail seniors, diaries captured additional 19% falls, while hotline added none. Among frail seniors, hotline added 16% falls, while diaries added 6%. The positive percent agreement between active-asking and diary was 100% among pre-frail and 88% among frail seniors. While monthly active-asking captures most falls in both groups, this method alone missed 19% of falls in pre-frail and 22% in frail seniors. Thus, a combination of active-asking and diaries for pre-frail, and active-asking and the hotline for frail seniors is warranted.

Falls and Fall-Related Injuries among Community-Dwelling Adults in the United States

PubMed Central

Verma, Santosh K.; Willetts, Joanna L.; Corns, Helen L.; Marucci-Wellman, Helen R.; Lombardi, David A.; Courtney, Theodore K.

2016-01-01

Introduction Falls are the leading cause of unintentional injuries in the U.S.; however, national estimates for all community-dwelling adults are lacking. This study estimated the national incidence of falls and fall-related injuries among community-dwelling U.S. adults by age and gender and the trends in fall-related injuries across the adult life span. Methods Nationally representative data from the National Health Interview Survey (NHIS) 2008 Balance and Dizziness supplement was used to develop national estimates of falls, and pooled data from the NHIS was used to calculate estimates of fall-related injuries in the U.S. and related trends from 2004–2013. Costs of unintentional fall-related injuries were extracted from the CDC’s Web-based Injury Statistics Query and Reporting System. Results Twelve percent of community-dwelling U.S. adults reported falling in the previous year for a total estimate of 80 million falls at a rate of 37.2 falls per 100 person-years. On average, 9.9 million fall-related injuries occurred each year with a rate of 4.38 fall-related injuries per 100 person-years. In the previous three months, 2.0% of older adults (65+), 1.1% of middle-aged adults (45–64) and 0.7% of young adults (18–44) reported a fall-related injury. Of all fall-related injuries among community-dwelling adults, 32.3% occurred among older adults, 35.3% among middle-aged adults and 32.3% among younger adults. The age-adjusted rate of fall-related injuries increased 4% per year among older women (95% CI 1%–7%) from 2004 to 2013. Among U.S. adults, the total lifetime cost of annual unintentional fall-related injuries that resulted in a fatality, hospitalization or treatment in an emergency department was 111 billion U.S. dollars in 2010. Conclusions Falls and fall-related injuries represent a significant health and safety problem for adults of all ages. The findings suggest that adult fall prevention efforts should consider the entire adult lifespan to ensure a

Monitoring and modeling ice-rock avalanches from ice-capped volcanoes: A case study of frequent large avalanches on Iliamna Volcano, Alaska

USGS Publications Warehouse

Huggel, C.; Caplan-Auerbach, J.; Waythomas, C.F.; Wessels, R.L.

2007-01-01

Iliamna is an andesitic stratovolcano of the Aleutian arc with regular gas and steam emissions and mantled by several large glaciers. Iliamna Volcano exhibits an unusual combination of frequent and large ice-rock avalanches in the order of 1 ?? 106??m3 to 3 ?? 107??m3 with recent return periods of 2-4??years. We have reconstructed an avalanche event record for the past 45??years that indicates Iliamna avalanches occur at higher frequency at a given magnitude than other mass failures in volcanic and alpine environments. Iliamna Volcano is thus an ideal site to study such mass failures and its relation to volcanic activity. In this study, we present different methods that fit into a concept of (1) long-term monitoring, (2) early warning, and (3) event documentation and analysis of ice-rock avalanches on ice-capped active volcanoes. Long-term monitoring methods include seismic signal analysis, and space-and airborne observations. Landsat and ASTER satellite data was used to study the extent of hydrothermally altered rocks and surface thermal anomalies at the summit region of Iliamna. Subpixel heat source calculation for the summit regions where avalanches initiate yielded temperatures of 307 to 613??K assuming heat source areas of 1000 to 25??m2, respectively, indicating strong convective heat flux processes. Such heat flow causes ice melting conditions and is thus likely to reduce the strength at the base of the glacier. We furthermore demonstrate typical seismic records of Iliamna avalanches with rarely observed precursory signals up to two hours prior to failure, and show how such signals could be used for a multi-stage avalanche warning system in the future. For event analysis and documentation, space- and airborne observations and seismic records in combination with SRTM and ASTER derived terrain data allowed us to reconstruct avalanche dynamics and to identify remarkably similar failure and propagation mechanisms of Iliamna avalanches for the past 45??years

Dementia as a risk factor for falls and fall injuries among nursing home residents.

PubMed

van Doorn, Carol; Gruber-Baldini, Ann L; Zimmerman, Sheryl; Hebel, J Richard; Port, Cynthia L; Baumgarten, Mona; Quinn, Charlene C; Taler, George; May, Conrad; Magaziner, Jay

2003-09-01

To compare rates of falling between nursing home residents with and without dementia and to examine dementia as an independent risk factor for falls and fall injuries. Prospective cohort study with 2 years of follow-up. Fifty-nine randomly selected nursing homes in Maryland, stratified by geographic region and facility size. Two thousand fifteen newly admitted residents aged 65 and older. During 2 years after nursing home admission, fall data were collected from nursing home charts and hospital discharge summaries. The unadjusted fall rate for residents in the nursing home with dementia was 4.05 per year, compared with 2.33 falls per year for residents without dementia (P<.0001). The effect of dementia on the rate of falling persisted when known risk factors were taken into account. Among fall events, those occurring to residents with dementia were no more likely to result in injury than falls of residents without dementia, but, given the markedly higher rates of falling by residents with dementia, their rate of injurious falls was higher than for residents without dementia. Dementia is an independent risk factor for falling. Although most falls do not result in injury, the fact that residents with dementia fall more often than their counterparts without dementia leaves them with a higher overall risk of sustaining injurious falls over time. Nursing home residents with dementia should be considered important candidates for fall-prevention and fall-injury-prevention strategies.

Fluid-rock Interactions recorded in Serpentinites subducted to 60-80 km Depth

NASA Astrophysics Data System (ADS)

Peters, D.; John, T.; Scambelluri, M.; Pettke, D. T.

2016-12-01

The HP metamorphic serpentinised peridotites of Erro-Tobbio (ET, Italy) offer a unique possibility to study fluid-rock interactions in subducted ultrabasic rocks that reached 550-650°C at 2-2.5 GPa. They contain metamorphic olivine + Ti-clinohumite in both the serpentinite matrix and veins cutting the rock foliation, interpreted to represent partial serpentinite dehydration fluid pathways [1,2] being variably retrogressed as e.g., indicated by chrysotile/lizardite mesh textures in vein olivine in strongly altered samples. This study aims to constraining the origin of fluid(s) and the scale(s) of fluid-rock interaction based on major to trace element systematics employing detailed bulk rock (nanoparticulate pressed powder pellet LA-ICP-MS [3] and ion chromatography / liquid ICP-MS analysis), and in situ mineral analysis (work in progress). Bulk data show moderate fluid-mobile element (FME) enrichment for Cs, Rb, Ba, Pb, As, and Sb (up to 100 times primitive mantle (PM)), W (1000 PM), and B (10000 PM). Alkali over U ratios of compiled serpentinite data (n ˜ 620) reveal distinctive global FME enrichment trends for MOR vs. forearc (FA) serpentinisation. ET serpentinites fall into the latter, indicating both sediment-equilibrated fluids and the preservation of characteristic FME enrichment patterns in HP serpentinites. Petrography reveals a multiphase evolution of the HP veins including retrograde serpentinisation, whereas serpentinite hosts have remained largely unaffected by retrogression. Comparison of vein vs. wall rock bulk data indicate vein-forming fluids in equilibrium with wall rocks, however, without evidence for external fluid ingress. The preservation of multiple fluid-rock interaction episodes and the lack of external fluid ingress in the ET HP serpentinites indicate near-closed system behaviour throughout subduction and imprint of characteristic fluid signatures onto the mantle. [1] Scambelluri et al. (1995) Geology, 23, 459-462. [2] John et al. (2011

MEMS-based sensing and algorithm development for fall detection and gait analysis

NASA Astrophysics Data System (ADS)

Gupta, Piyush; Ramirez, Gabriel; Lie, Donald Y. C.; Dallas, Tim; Banister, Ron E.; Dentino, Andrew

2010-02-01

Falls by the elderly are highly detrimental to health, frequently resulting in injury, high medical costs, and even death. Using a MEMS-based sensing system, algorithms are being developed for detecting falls and monitoring the gait of elderly and disabled persons. In this study, wireless sensors utilize Zigbee protocols were incorporated into planar shoe insoles and a waist mounted device. The insole contains four sensors to measure pressure applied by the foot. A MEMS based tri-axial accelerometer is embedded in the insert and a second one is utilized by the waist mounted device. The primary fall detection algorithm is derived from the waist accelerometer. The differential acceleration is calculated from samples received in 1.5s time intervals. This differential acceleration provides the quantification via an energy index. From this index one may ascertain different gait and identify fall events. Once a pre-determined index threshold is exceeded, the algorithm will classify an event as a fall or a stumble. The secondary algorithm is derived from frequency analysis techniques. The analysis consists of wavelet transforms conducted on the waist accelerometer data. The insole pressure data is then used to underline discrepancies in the transforms, providing more accurate data for classifying gait and/or detecting falls. The range of the transform amplitude in the fourth iteration of a Daubechies-6 transform was found sufficient to detect and classify fall events.

Fall episodes in elderly patients with asthma and COPD - a pilot study.

PubMed

Bozek, Andrzej; Jarzab, Jerzy; Hadas, Ewa; Jakalski, Marek; Canonica, Giorgio Walter

2018-05-08

Evidence of an increased risk of falls in patients with chronic obstructive pulmonary disease (COPD) exists; however, this has not been studied in elderly asthmatic patients. The aim of the study was to determine the incidence of falls in elderly patients who were diagnosed with bronchial asthma compared to subjects with COPD. A 12 - month prospective observational study in elderly outpatients with diagnosis of either asthma or COPD was conducted. All of the participants were monitored on the following parameters: falls, comorbidities, drug therapy and The Berg Balance Scale. The rate of falls was shown as an incidence ratio. Cluster analysis for subgroups with similar features was performed on all patients included in the study. Two clusters of frequent fallers were determined. The fall incidence rate in falls per person per year was 1.41 (95% CI: 0.86-1.96) in asthmatic patients and 1.49 (95% CI: 1.05-2.11) in the COPD group. Frequent fallers were more prevalent in the COPD group, with 32% in this group compared to 28% in the groups of patients with asthma. In cluster analysis, frequent fallers were grouped into two models characterized by polytherapy, depression symptoms, hospitalizations, coronary disease, dementia and diagnosis of COPD or asthma. Elderly asthmatic patients presented a high rate of falls, which is comparable to that of patients with COPD.

Rock burst governance of working face under igneous rock

NASA Astrophysics Data System (ADS)

Chang, Zhenxing; Yu, Yue

2017-01-01

As a typical failure phenomenon, rock burst occurs in many mines. It can not only cause the working face to cease production, but also cause serious damage to production equipment, and even result in casualties. To explore how to govern rock burst of working face under igneous rock, the 10416 working face in some mine is taken as engineering background. The supports damaged extensively and rock burst took place when the working face advanced. This paper establishes the mechanical model and conducts theoretical analysis and calculation to predict the fracture and migration mechanism and energy release of the thick hard igneous rock above the working face, and to obtain the advancing distance of the working face when the igneous rock fractures and critical value of the energy when rock burst occurs. Based on the specific conditions of the mine, this paper put forward three kinds of governance measures, which are borehole pressure relief, coal seam water injection and blasting pressure relief.

Landslide monitoring and early warning systems in Lower Austria - current situation and new developments

NASA Astrophysics Data System (ADS)

Thiebes, Benni; Glade, Thomas; Schweigl, Joachim; Jäger, Stefan; Canli, Ekrem

2014-05-01

Landslides represent significant hazards in the mountainous areas of Austria. The Regional Geological Surveys are responsible to inform and protect the population, and to mitigate damage to infrastructure. Efforts of the Regional Geological Survey of Lower Austria include detailed site investigations, the planning and installation of protective structures (e.g. rock fall nets) as well as preventive measures such as regional scale landslide susceptibility assessments. For potentially endangered areas, where protection works are not feasible or would simply be too costly, monitoring systems have been installed. However, these systems are dominantly not automatic and require regular field visits to take measurements. Therefore, it is difficult to establish any relation between initiating and controlling factors, thus to fully understand the underlying process mechanism which is essential for any early warning system. Consequently, the implementation of new state-of-the-art monitoring and early warning systems has been started. In this presentation, the design of four landslide monitoring and early warning systems is introduced. The investigated landslide process types include a deep-seated landslide, a rock fall site, a complex earth flow, and a debris flow catchment. The monitoring equipment was chosen depending on the landslide processes and their activity. It aims to allow for a detailed investigation of process mechanisms in relation to its triggers and for reliable prediction of future landslide activities. The deep-seated landslide will be investigated by manual and automatic inclinometers to get detailed insights into subsurface displacements. In addition, TDR sensors and a weather station will be employed to get a better understanding on the influence of rainfall on sub-surface hydrology. For the rockfall site, a wireless sensor network will be installed to get real-time information on acceleration and inclination of potentially unstable blocks. The movement

Highlights from two years of geoelectrical monitoring of permafrost at the Magnetköpfl/Kitzsteinhorn

NASA Astrophysics Data System (ADS)

Jochum, Birgit; Ottowitz, David; Pfeiler, Stefan; Supper, Robert; Keuschnig, Markus; Hartmeyer, Ingo; Kim, Jung-Ho

2014-05-01

Changes of climate parameters due to global warming generate increased permafrost warming and deglaciation in alpine regions. The area of interest is the Magnetköpfl, a peak below the Kitzsteinhorn (3203 m), where scientists observe increasing rock instability due to the probable degradation of permafrost and the rapid lowering of the glacier surfaces adjacent to the rock faces (loss of natural abutment, exposure of rock to atmospheric influences). Geoelectric measurements are an adequate method to measure permafrost, since the underground electric resistivity is highly dependent on temperature and the amount of unfrozen pore water. In October 2011 a geoelectrical monitoring profile with the GEOMON4D was installed on the north facing ridge of the Magnetköpfl. Measurements of soil temperature on the profile support the interpretation of geoelectric data. Maximum active layer depth at the Magnetköpfl is approximately 3 m. Seasonal variations of ground temperature can be observed up to a depth of 8-10 m below surface. The two year period of data collection allows us to analyse time series of average apparent resistivities compared with the climatic seasons. It can be seen that different temperature periods have a direct correlation to average apparent resistivity. Inversion results of geoelectrical monitoring data are derived from an innovative 4D resistivity inversion approach (Kim et al, 2013). In three selected events (thawing and freezing in spring, thawing in summer, freezing in fall) difference images of the 4D inversion show the depth range of the temperature influence. The temperature sensors at the profile only reach 0.8 m below ground level.The geoelectrical monitoring data is able to deliver far more (thermal) information than single point temperature measurements since the underground electric resistivity is highly dependent on temperature. The geoelectrical monitoring is supported by the project "TEMPEL", funded by the Federal Ministry for Transport

Geotechnical Descriptions of Rock and Rock Masses.

DTIC Science & Technology

1985-04-01

determined in the field on core speci ns by the standard Rock Testing Handbook Methods . afls GA DTIC TAB thannounod 13 Justifiatlo By Distributin...to provide rock strength descriptions from the field. The point-load test has proven to be a reliable method of determining rock strength properties...report should qualify the reported spacing values by stating the methods used to determine spacing. Preferably the report should make the determination

Hydraulic tomography offers improved imaging of heterogeneity in fractured rocks.

PubMed

Illman, Walter A

2014-01-01

Fractured rocks have presented formidable challenges for accurately predicting groundwater flow and contaminant transport. This is mainly due to our difficulty in mapping the fracture-rock matrix system, their hydraulic properties and connectivity at resolutions that are meaningful for groundwater modeling. Over the last several decades, considerable effort has gone into creating maps of subsurface heterogeneity in hydraulic conductivity (K) and specific storage (Ss ) of fractured rocks. Developed methods include kriging, stochastic simulation, stochastic inverse modeling, and hydraulic tomography. In this article, I review the evolution of various heterogeneity mapping approaches and contend that hydraulic tomography, a recently developed aquifer characterization technique for unconsolidated deposits, is also a promising approach in yielding robust maps (or tomograms) of K and Ss heterogeneity for fractured rocks. While hydraulic tomography has recently been shown to be a robust technique, the resolution of the K and Ss tomograms mainly depends on the density of pumping and monitoring locations and the quality of data. The resolution will be improved through the development of new devices for higher density monitoring of pressure responses at discrete intervals in boreholes and potentially through the integration of other data from single-hole tests, borehole flowmeter profiling, and tracer tests. Other data from temperature and geophysical surveys as well as geological investigations may improve the accuracy of the maps, but more research is needed. Technological advances will undoubtedly lead to more accurate maps. However, more effort should go into evaluating these maps so that one can gain more confidence in their reliability. © 2013, National Ground Water Association.

Hydraulic tomography offers improved imaging of heterogeneity in fractured rocks

NASA Astrophysics Data System (ADS)

Illman, W. A.

2013-12-01

Fractured rocks have presented formidable challenges for accurately predicting groundwater flow and contaminant transport. This is mainly due to our difficulty in mapping the fracture-rock matrix system, their hydraulic properties and connectivity at resolutions that are meaningful for groundwater flow and especially transport modeling. Over the last several decades, considerable effort has gone into creating maps of subsurface heterogeneity in hydraulic conductivity (K) and specific storage (Ss) of fractured rocks. Developed methods include kriging, stochastic simulation, stochastic inverse modeling, and hydraulic tomography. In this presentation, I review the evolution of various heterogeneity mapping approaches and contend that hydraulic tomography, a recently developed aquifer characterization technique for unconsolidated deposits, is also a promising approach in yielding robust maps (or tomograms) of K and Ss heterogeneity for fractured rocks. While hydraulic tomography has recently been shown to be a robust technique, the resolution of the K and Ss tomograms mainly depends on the density of pumping and monitoring locations and the quality of data. The resolution will be improved through the development of new devices for higher density monitoring of pressure responses at discrete intervals in boreholes and potentially through the integration of other data from single-hole tests, borehole flowmeter profiling and tracer tests. Other data from temperature and geophysical surveys as well as geological investigations may improve the accuracy of the maps, but more research is needed. Technological advances will undoubtedly lead to more accurate maps. However, more effort should go into evaluating these maps so that one can gain more confidence in their reliability.

Data Validation Package September 2016 Groundwater and Surface Water Sampling at the Slick Rock, Colorado, Processing Sites January 2017

DOE Office of Scientific and Technical Information (OSTI.GOV)

Traub, David; Nguyen, Jason

The Slick Rock, Colorado, Processing Sites are referred to as the Slick Rock West Processing Site (SRK05) and the Slick Rock East Processing Site (SRK06). This annual event involved sampling both sites for a total of 16 monitoring wells and 6 surface water locations as required by the 2006 Draft Final Ground Water Compliance Action Plan for the Slick Rock, Colorado, Processing Sites (GCAP). A domestic well was also sampled at a property adjacent to the Slick Rock East site at the request of the landowner.

Evaluation of Sensor Technology to Detect Fall Risk and Prevent Falls in Acute Care.

PubMed

Potter, Patricia; Allen, Kelly; Costantinou, Eileen; Klinkenberg, William Dean; Malen, Jill; Norris, Traci; O'Connor, Elizabeth; Roney, Wilhemina; Tymkew, Heidi Hahn; Wolf, Laurie

2017-08-01

Sensor technology that dynamically identifies hospitalized patients' fall risk and detects and alerts nurses of high-risk patients' early exits out of bed has potential for reducing fall rates and preventing patient harm. During Phase 1 (August 2014-January 2015) of a previously reported performance improvement project, an innovative depth sensor was evaluated on two inpatient medical units to study fall characteristics. In Phase 2 (April 2015-January 2016), a combined depth and bed sensor system designed to assign patient fall probability, detect patient bed exits, and subsequently prevent falls was evaluated. Fall detection depth sensors remained in place on two medicine units; bed sensors used to detect patient bed exits were added on only one of the medicine units. Fall rates and fall with injury rates were evaluated on both units. During Phase 2, the designated evaluation unit had 14 falls, for a fall rate of 2.22 per 1,000 patient-days-a 54.1% reduction compared with the Phase 1 fall rate. The difference in rates from Phase 1 to Phase 2 was statistically significant (z = 2.20; p = 0.0297). The comparison medicine unit had 30 falls-a fall rate of 4.69 per 1,000 patient-days, representing a 57.9% increase as compared with Phase 1. A fall detection sensor system affords a level of surveillance that standard fall alert systems do not have. Fall prevention remains a complex issue, but sensor technology is a viable fall prevention option. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Talking Rocks.

ERIC Educational Resources Information Center

Rice, Dale; Corley, Brenda

1987-01-01

Discusses some of the ways that rocks can be used to enhance children's creativity and their interest in science. Suggests the creation of a dramatic production involving rocks. Includes basic information on sedimentary, igneous, and metamorphic rocks. (TW)

Validation of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm

PubMed Central

Lawson, Sara Nicole; Zaluski, Neal; Petrie, Amanda; Arnold, Cathy; Basran, Jenny

2013-01-01

ABSTRACT Purpose: To investigate the concurrent validity of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm (FSRA). Method: A total of 29 older adults (mean age 77.7 [SD 4.0] y) residing in an independent-living senior's complex who met inclusion criteria completed a demographic questionnaire and the components of the FSRA and Berg Balance Scale (BBS). The FSRA consists of the Elderly Fall Screening Test (EFST) and the Multi-factor Falls Questionnaire (MFQ); it is designed to categorize individuals into low, moderate, or high fall-risk categories to determine appropriate management pathways. A predictive model for probability of fall risk, based on previous research, was used to determine concurrent validity of the FSRI. Results: The FSRA placed 79% of participants into the low-risk category, whereas the predictive model found the probability of fall risk to range from 0.04 to 0.74, with a mean of 0.35 (SD 0.25). No statistically significant correlation was found between the FSRA and the predictive model for probability of fall risk (Spearman's ρ=0.35, p=0.06). Conclusion: The FSRA lacks concurrent validity relative to to a previously established model of fall risk and appears to over-categorize individuals into the low-risk group. Further research on the FSRA as an adequate tool to screen community-dwelling older adults for fall risk is recommended. PMID:24381379

Automated Fall Detection With Quality Improvement “Rewind” to Reduce Falls in Hospital Rooms

PubMed Central

Rantz, Marilyn J.; Banerjee, Tanvi S.; Cattoor, Erin; Scott, Susan D.; Skubic, Marjorie; Popescu, Mihail

2014-01-01

The purpose of this study was to test the implementation of a fall detection and “rewind” privacy-protecting technique using the Microsoft® Kinect™ to not only detect but prevent falls from occurring in hospitalized patients. Kinect sensors were placed in six hospital rooms in a step-down unit and data were continuously logged. Prior to implementation with patients, three researchers performed a total of 18 falls (walking and then falling down or falling from the bed) and 17 non-fall events (crouching down, stooping down to tie shoe laces, and lying on the floor). All falls and non-falls were correctly identified using automated algorithms to process Kinect sensor data. During the first 8 months of data collection, processing methods were perfected to manage data and provide a “rewind” method to view events that led to falls for post-fall quality improvement process analyses. Preliminary data from this feasibility study show that using the Microsoft Kinect sensors provides detection of falls, fall risks, and facilitates quality improvement after falls in real hospital environments unobtrusively, while taking into account patient privacy. PMID:24296567

Data Validation Package: April 2016 Groundwater Sampling at the Falls City, Texas, Disposal Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jasso, Tashina; Widdop, Michael

Nine groundwater samples were collected at the Falls City, Texas, Disposal Site as specified in the March 2008 Long-Term Surveillance Plan for the US Department of Energy Falls City Uranium Mill Tailings Disposal Site, Falls City, Texas (DOE-LM/1602-2008). Sampling and analyses were conducted as specified in the Sampling and Analysis Plan for US Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). The wells sampled included the cell performance monitoring wells (0709, 0858, 0880, 0906, and 0921) and the groundwater monitoring wells (0862, 0886, 0891, 0924, and 0963). A duplicate sample was collected from location 0891. Water levelsmore » were measured at each sampled well. Historically, cell performance monitoring wells 0908 and 0916 have not produced water and were confirmed as dry during this sampling event. These wells are completed above the saturated interval in the formation. Notable observations for time-concentration graphs in this report include: (1) uranium concentrations in well 0891 continue to increase; (2) the uranium concentration in well 0880 is higher than the 2015 value and lower than the 2014 value, and it remains within the range of historical values; and (3) uranium concentrations in the other sampled wells are below 2 mg/L and consistent with previous results.« less

Volumetric measurement of rock movement using photogrammetry

PubMed Central

Benton, Donovan J.; Iverson, Stephen R.; Martin, Lewis A.; Johnson, Jeffrey C.; Raffaldi, Michael J.

2016-01-01

NIOSH ground control safety research program at Spokane, Washington, is exploring applications of photogrammetry to rock mass and support monitoring. This paper describes two ways photogrammetric techniques are being used. First, photogrammetric data of laboratory testing is being used to correlate energy input and support deformation. This information can be used to infer remaining support toughness after ground deformation events. This technique is also demonstrated in a field application. Second, field photogrammetric data is compared to crackmeter data from a deep underground mine. Accuracies were found to average 8 mm, but have produced results within 0.2 mm of true displacement, as measured by crackmeters. Application of these techniques consists of monitoring overall fault activity by monitoring multiple points around the crackmeter. A case study is provided in which a crackmeter is clearly shown to have provided insufficient information regarding overall fault ground deformation. Photogrammetry is proving to be a useful ground monitoring tool due to its unobtrusiveness and ease of use. PMID:27110429

Falls in multiple sclerosis.

PubMed

Matsuda, Patricia N; Shumway-Cook, Anne; Bamer, Alyssa M; Johnson, Shana L; Amtmann, Dagmar; Kraft, George H

2011-07-01

To examine incidence, associated factors, and health care provider (HCP) response to falls in persons with multiple sclerosis (MS). Cross-sectional retrospective design. Community setting. Four hundred seventy-four persons with MS. Mailed survey questionnaire examined incidence, risk factors, and HCP response to falls in persons with MS who were dwelling in the community. Univariate and multiple ordinal regression analysis identified variables associated with single and multiple falls. Falls, causes and perceived reasons for falls, and HCP response. A total of 265 participants (58.2%) reported one or more falls in the previous 6 months, and 58.5% of falls were medically injurious. Trips/slips while walking accounted for 48% of falls. Factors associated with falls included use of a cane or walker (odds ratio [OR] 2.62; 95% confidence interval [CI] 1.66-4.14), income <$25,000 (OR 1.85; 95% CI 1.13-3.04), balance problems (OR 1.28; 95% CI 1.11-1.49), and leg weakness (OR 1.26; 95% CI 1.09-1.46). Fifty-one percent of those who fell (135/265) reported speaking to an HCP about their falls; recommended strategies included safety strategies (53.2%), use of gait assistive devices (42.1%), exercise/balance training (22.2%), and home modifications (16.6%). Factors associated with falls in persons with MS are similar to those in other populations with neurologic diseases. Despite the high incidence of falls, fewer than 50% of people with MS receive information about prevention of falls from an HCP. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Preventing falls

MedlinePlus

... page: //medlineplus.gov/ency/patientinstructions/000052.htm Preventing falls To use the sharing features on this page, please enable JavaScript. People with medical problems are at risk of falling or tripping. This can result in ...

Conditioning of sandhill cranes during fall migration

USGS Publications Warehouse

Krapu, Gary L.; Johnson, Douglas H.

1990-01-01

Body mass of adult female and male sandhill cranes (Grus canadensis) increased an average of 17 and 20%, respectively, from early September to late October on staging areas in central North Dakota and varied by year. Increases in body mass averaged 550 and 681 g among female and male G. c. canadensis, respectively, and 616 and 836 g among female and male G. c. rowani. Adult and juvenile G. c. rowani were lean at arrival, averaging 177 and 83 g of fat, respectively, and fat reserves increased to 677 and 482 g by mid-October. Fat-free dry mass increased by 12% among juveniles, reflecting substantial growth, but remained constant among adults. The importance of fall staging areas as conditioning sites for sandhill cranes, annual variation in body mass, and vulnerability of cranes to habitat loss underscore the need to monitor status of fall staging habitat in the northern plains region and to take steps to maintain suitable habitat where necessary.

Nurses' Perceptions of Implementing Fall Prevention Interventions to Mitigate Patient-Specific Fall Risk Factors.

PubMed

Wilson, Deleise S; Montie, Mary; Conlon, Paul; Reynolds, Margaret; Ripley, Robert; Titler, Marita G

2016-08-01

Evidence-based (EB) fall prevention interventions to mitigate patient-specific fall risk factors are readily available but not routinely used in practice. Few studies have examined nurses' perceptions about both the use of these EB interventions and implementation strategies designed to promote their adoption. This article reports qualitative findings of nurses' perceptions about use of EB fall prevention interventions to mitigate patient-specific fall risks, and implementation strategies to promote use of these interventions. The findings revealed five major themes: before-study fall prevention practices, use of EB fall prevention interventions tailored to patient-specific fall risk factors, beneficial implementation strategies, overall impact on approach to fall prevention, and challenges These findings are useful to guide nurses' engagement and use of EB fall prevention practices tailored to patient-specific fall risk factors. © The Author(s) 2016.

Art Rocks with Rock Art!

ERIC Educational Resources Information Center

Bickett, Marianne

2011-01-01

This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

Snow-cover dynamics monitored by automatic digital photography at the rooting zone of an active rock glacier in the Hinteres Lantal Cirque, Austria

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas; Rieckh, Matthias; Avian, Michael

2010-05-01

Knowledge regarding snow-cover dynamics and climatic conditions in the rooting zone of active rock glaciers is still limited. The number of meteorological stations on the surface of or close to active rock glaciers is increasing. However, areal information on snow-cover distribution and its spatial dynamics caused by different processes on rock glaciers surfaces with a high temporal resolution from such remote alpine areas are mostly difficult to obtain. To face this problem an automatic remote digital camera (RDC) system was proprietary developed. The core parts of the RDC system are a standard hand-held digital camera, a remote control, a water proof casing with a transparent opening, a 12V/25Ah battery and solar panels with a charge controller. Three such devices were constructed and installed at different sites in the Central Alps of Austria. One RDC system is used to monitor the rooting zone of the highly active rock glacier in the Hinteres Langtal Cirque (46°59'N, 12°47'E), Central Schober Mountains, Austria. The 0.15 km² large NW-facing rock glaciers is tongue-shaped with a fast moving lower part (>1m/a) and a substantially slower upper part, ranging in elevation between 2455-2700 m a.s.l. The RDC system was set up in September 2006 and is located since than at 2770 m a.s.l. on a pronounced ridge crest that confines the Hinteres Langtal Cirque to the SW. The water proof casing was attached to a 1.5 m high metal pole which itself was fixed to the bedrock by screws and concrete glue. The viewing direction of the camera is NE. Hence, the image section of the RDC focuses on the rooting zone of the rock glacier and its headwalls up to c. 3000 m a.s.l. Photographs were taken daily at 3 pm providing the optimal lighting conditions in the relevant part of the cirque. 720 photographs were taken continuously in the period 12.09.2006 to 31.08.2008. These optical data were analysed by applying GIS and remote sensing techniques regarding snow-cover distribution

Meteorite falls in Africa

NASA Astrophysics Data System (ADS)

Khiri, Fouad; Ibhi, Abderrahmane; Saint-Gerant, Thierry; Medjkane, Mohand; Ouknine, Lahcen

2017-10-01

The study of meteorites provides insight into the earliest history of our solar system. From 1800, about the year meteorites were first recognized as objects falling from the sky, until December 2014, 158 observed meteorite falls were recorded in Africa. Their collected mass ranges from 1.4 g to 175 kg with the 1-10 kg cases predominant. The average rate of African falls is low with only one fall recovery per 1.35-year time interval (or 0.023 per year per million km2). This African collection is dominated by ordinary chondrites (78%) just like in the worldwide falls. The seventeen achondrites include three Martian meteorite falls (Nakhla of Egypt, Tissint of Morocco and Zagami of Nigeria). Observed Iron meteorite falls are relatively rare and represent only 5%. The falls' rate in Africa is variable in time and in space. The number of falls continues to grow since 1860, 80% of which were recovered during the period between 1910 and 2014. Most of these documented meteorite falls have been recovered from North-Western Africa, Eastern Africa and Southern Africa. They are concentrated in countries which have a large surface area and a large population with a uniform distribution. Other factors are also favorable for observing and collecting meteorite falls across the African territory, such as: a genuine meteorite education, a semi-arid to arid climate (clear sky throughout the year most of the time), croplands or sparse grasslands and possible access to the fall location with a low percentage of forest cover and dense road network.

Falls among union carpenters.

PubMed

Lipscomb, Hester J; Li, Leiming; Dement, John M

2003-08-01

Falls are a leading cause of morbidity and mortality in the construction trades. We identified a cohort of 16,215 active union carpenters, hours worked, and their workers' compensation claims for a 10-year period. The data on this well-defined cohort were used to describe their work-related falls; to define rates of injury and the associated costs; and to identify high-risk groups. Same level falls occurred at a rate of 1.8/200,000 hours worked; falls from elevations at a rate of 2.3/200,000 hours worked. These injuries resulted in direct payments of 0.30 dollars per hour of work or 2.40 dollars per 8-hr day. Mean costs per fall increased with increasing age. Age was not associated with risk of falls from elevations; younger carpenters had modestly reduced rates of falls from the same level. Rates of falls decreased with increasing time in the union. Carpenters whose usual work involved drywall installation or residential work were at highest risk. Falls are a significant public health risk for carpenters and they are responsible for a significant burden of work-related injury costs. While there is a need for prevention of falls from elevations--through training, enforcement of fall protection regulations, improved safety climate, or engineering changes--there is also the need to prevent falls from lower elevations. Differences in risk likely reflect varying exposures and safety practices in different areas of carpentry, as well as training, experience, and job assignments based on longevity in the union. Copyright 2003 Wiley-Liss, Inc.

Medication Use, Falls, and Fall-Related Worry in Older Adults in the United States.

PubMed

Watanabe, Jonathan H

2016-07-01

To compare the prevalence of falls and fall-related concerns of medication users versus nonusers in U.S. seniors. Cross-sectional study. The National Health and Aging Trends Study. U.S. nationally representative sample of Medicare beneficiaries in 2011. Comparing subjects who used medications with subjects who did not in the past month, the outcomes were percentages of subjects who experienced 1) a fall in the past month, 2) worry about falling in the past month, 3) being limited by this worry in the past month, 4) a fall in the past year. A greater percentage of medication users experienced falls and fall-related outcomes, compared with non-medication users. Among medication users, 10.29% had a past month fall, compared with 5.42% of non-medication users; 27.69% of medication users worried in the past month about falling, compared with 9.15% of non-medication users; 40.96% of medication users were limited by this worry, compared with 21.21%; 22.82% of medication users had a fall in the past year, compared with 13.15% of non-medication users. Seniors who use medications are more likely to fall and to be concerned about falling. Pharmacist involvement in fall prevention continues to be essential.

ROCK Inhibitor Enhances Adhesion and Wound Healing of Human Corneal Endothelial Cells

PubMed Central

Pipparelli, Aurélien; Arsenijevic, Yvan; Thuret, Gilles; Gain, Philippe

2013-01-01

Maintenance of corneal transparency is crucial for vision and depends mainly on the endothelium, a non-proliferative monolayer of cells covering the inner part of the cornea. When endothelial cell density falls below a critical threshold, the barrier and “pump” functions of the endothelium are compromised which results in corneal oedema and loss of visual acuity. The conventional treatment for such severe disorder is corneal graft. Unfortunately, there is a worldwide shortage of donor corneas, necessitating amelioration of tissue survival and storage after harvesting. Recently it was reported that the ROCK inhibitor Y-27632 promotes adhesion, inhibits apoptosis, increases the number of proliferating monkey corneal endothelial cells in vitro and enhance corneal endothelial wound healing both in vitro and in vivo in animal models. Using organ culture human cornea (N = 34), the effect of ROCK inhibitor was evaluated in vitro and ex vivo. Toxicity, corneal endothelial cell density, cell proliferation, apoptosis, cell morphometry, adhesion and wound healing process were evaluated by live/dead assay standard cell counting method, EdU labelling, Ki67, Caspase3, Zo-1 and Actin immunostaining. We demonstrated for the first time in human corneal endothelial cells ex vivo and in vitro, that ROCK inhibitor did not induce any toxicity effect and did not alter cell viability. ROCK inhibitor treatment did not induce human corneal endothelial cells proliferation. However, ROCK inhibitor significantly enhanced adhesion and wound healing. The present study shows that the selective ROCK inhibitor Y-27632 has no effect on human corneal endothelial cells proliferative capacities, but alters cellular behaviours. It induces changes in cell shape, increases cell adhesion and enhances wound healing ex vivo and in vitro. Its absence of toxicity, as demonstrated herein, is relevant for its use in human therapy. PMID:23626771

A Successful ED Fall Risk Program Using the KINDER 1 Fall RiskAssessment Tool.

PubMed

Townsend, Ann B; Valle-Ortiz, Marisol; Sansweet, Tracy

2016-11-01

Emergency nurses did not perform falls risk assessments routinely on our ED patients; the instrument used was aimed at inpatients. We identified a need to revise fall assessment practices specific to our emergency department. The purpose of the performance improvement project was to reduce ED falls and evaluate the use of an ED-specific fall risk tool, the KINDER 1 Fall Risk Assessment. The plan was to establish fall risk assessment practices at point of ED entry and to decrease total falls. We retrospectively reviewed ED fall data for each quarter of 2013, which included risk assessments scores, the total number of falls, and the circumstances of each fall. Using Kotter's framework to guide a successful change process, we implemented the KINDER 1 to assess fall risk. During the first 4 weeks of the project, 937 patients (27%) were identified as high risk for falls using the KINDER 1. During the subsequent 3 quarters, the total number of falls decreased; reported falls without injuries dropped from 0.21 to 0.07 per 1000 patients, and falls with injuries were reduced from 0.21 to 0.0 per 1000 patients. The results of this project represented a valuable step toward achieving our goal to keep ED patients safe from injuries as a result of falls. The findings add to the body of nursing knowledge on the application of clinical-based performance improvement projects to improve patient outcomes and to provide data on the use of the KINDER 1 tool, which has not been extensively tested. Copyright © 2016 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

Natural radionuclides in the rocks of the Valle del Cervo Pluton in Piedmont.

PubMed

Sesana, Lucia; Fumagalli, Marco; Carnevale, Mauro; Polla, Giancarla; Facchini, Ugo; Colombo, Annita; Tunesi, Annalisa; De Capitani, Luisa; Rusconi, Rosella

2006-01-01

Monitoring of the gamma radiation in Valle del Cervo Pluton was performed by determining U and Th contents in the main rock types cropping out over the entire area and pertaining to the granitic complex, syenitic complex and monzonitic complex. In particular, syenitic rocks were largely used as building and ornamental materials (e.g. Sienite della Balma). All the samples are fresh and do not present joints or fractures filled with U minerals. In the crushed samples the activity of uranium varies from 346 to 764 Bq/kg. Concentration of thorium varies from 202 to 478 Bq/kg. For all the analysed rocks uranium activity is higher than thorium one. The lowest value of radioactive concentration is referred to rocks of the granitic complex. The most active rocks are syenites. The data confirm the high activities of Valle del Cervo rock types, strongly connected with high K content of the source magma (geochemical signature); on the contrary, the activity seems to be not related to the location of the samples.

Deformation mechanisms in a coal mine roadway in extremely swelling soft rock.

PubMed

Li, Qinghai; Shi, Weiping; Yang, Renshu

2016-01-01

The problem of roadway support in swelling soft rock was one of the challenging problems during mining. For most geological conditions, combinations of two or more supporting approaches could meet the requirements of most roadways; however, in extremely swelling soft rock, combined approaches even could not control large deformations. The purpose of this work was to probe the roadway deformation mechanisms in extremely swelling soft rock. Based on the main return air-way in a coal mine, deformation monitoring and geomechanical analysis were conducted, as well as plastic zone mechanical model was analysed. Results indicated that this soft rock was potentially very swelling. When the ground stress acted alone, the support strength needed in situ was not too large and combined supporting approaches could meet this requirement; however, when this potential released, the roadway would undergo permanent deformation. When the loose zone reached 3 m within surrounding rock, remote stress p ∞ and supporting stress P presented a linear relationship. Namely, the greater the swelling stress, the more difficult it would be in roadway supporting. So in this extremely swelling soft rock, a better way to control roadway deformation was to control the releasing of surrounding rock's swelling potential.

Experimental Study on the Coupling Mechanism of Early-strength Backfill and Rock

NASA Astrophysics Data System (ADS)

Wang, Mingxu