Sample records for key geomechanics issues

  1. Comparison of geomechanical deformation induced by megatonne-scale CO2 storage at Sleipner, Weyburn, and In Salah

    PubMed Central

    Verdon, James P.; Kendall, J.-Michael; Stork, Anna L.; Chadwick, R. Andy; White, Don J.; Bissell, Rob C.

    2013-01-01

    Geological storage of CO2 that has been captured at large, point source emitters represents a key potential method for reduction of anthropogenic greenhouse gas emissions. However, this technology will only be viable if it can be guaranteed that injected CO2 will remain trapped in the subsurface for thousands of years or more. A significant issue for storage security is the geomechanical response of the reservoir. Concerns have been raised that geomechanical deformation induced by CO2 injection will create or reactivate fracture networks in the sealing caprocks, providing a pathway for CO2 leakage. In this paper, we examine three large-scale sites where CO2 is injected at rates of ∼1 megatonne/y or more: Sleipner, Weyburn, and In Salah. We compare and contrast the observed geomechanical behavior of each site, with particular focus on the risks to storage security posed by geomechanical deformation. At Sleipner, the large, high-permeability storage aquifer has experienced little pore pressure increase over 15 y of injection, implying little possibility of geomechanical deformation. At Weyburn, 45 y of oil production has depleted pore pressures before increases associated with CO2 injection. The long history of the field has led to complicated, sometimes nonintuitive geomechanical deformation. At In Salah, injection into the water leg of a gas reservoir has increased pore pressures, leading to uplift and substantial microseismic activity. The differences in the geomechanical responses of these sites emphasize the need for systematic geomechanical appraisal before injection in any potential storage site. PMID:23836635

  2. Comparison of geomechanical deformation induced by megatonne-scale CO2 storage at Sleipner, Weyburn, and In Salah.

    PubMed

    Verdon, James P; Kendall, J-Michael; Stork, Anna L; Chadwick, R Andy; White, Don J; Bissell, Rob C

    2013-07-23

    Geological storage of CO2 that has been captured at large, point source emitters represents a key potential method for reduction of anthropogenic greenhouse gas emissions. However, this technology will only be viable if it can be guaranteed that injected CO2 will remain trapped in the subsurface for thousands of years or more. A significant issue for storage security is the geomechanical response of the reservoir. Concerns have been raised that geomechanical deformation induced by CO2 injection will create or reactivate fracture networks in the sealing caprocks, providing a pathway for CO2 leakage. In this paper, we examine three large-scale sites where CO2 is injected at rates of ~1 megatonne/y or more: Sleipner, Weyburn, and In Salah. We compare and contrast the observed geomechanical behavior of each site, with particular focus on the risks to storage security posed by geomechanical deformation. At Sleipner, the large, high-permeability storage aquifer has experienced little pore pressure increase over 15 y of injection, implying little possibility of geomechanical deformation. At Weyburn, 45 y of oil production has depleted pore pressures before increases associated with CO2 injection. The long history of the field has led to complicated, sometimes nonintuitive geomechanical deformation. At In Salah, injection into the water leg of a gas reservoir has increased pore pressures, leading to uplift and substantial microseismic activity. The differences in the geomechanical responses of these sites emphasize the need for systematic geomechanical appraisal before injection in any potential storage site.

  3. The Geomechanics of CO 2 Storage in Deep Sedimentary Formations

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

    Rutqvist, Jonny

    2012-01-12

    This study provides a review of the geomechanics and modeling of geomechanics associated with geologic carbon storage (GCS), focusing on storage in deep sedimentary formations, in particular saline aquifers. The paper first introduces the concept of storage in deep sedimentary formations, the geomechanical processes and issues related with such an operation, and the relevant geomechanical modeling tools. This is followed by a more detailed review of geomechanical aspects, including reservoir stress-strain and microseismicity, well integrity, caprock sealing performance, and the potential for fault reactivation and notable (felt) seismic events. Geomechanical observations at current GCS field deployments, mainly at the Inmore » Salah CO 2 storage project in Algeria, are also integrated into the review. The In Salah project, with its injection into a relatively thin, low-permeability sandstone is an excellent analogue to the saline aquifers that might be used for large scale GCS in parts of Northwest Europe, the U.S. Midwest, and China. Some of the lessons learned at In Salah related to geomechanics are discussed, including how monitoring of geomechanical responses is used for detecting subsurface geomechanical changes and tracking fluid movements, and how such monitoring and geomechanical analyses have led to preventative changes in the injection parameters. Recently, the importance of geomechanics has become more widely recognized among GCS stakeholders, especially with respect to the potential for triggering notable (felt) seismic events and how such events could impact the long-term integrity of a CO 2 repository (as well as how it could impact the public perception of GCS). As described in the paper, to date, no notable seismic event has been reported from any of the current CO 2 storage projects, although some unfelt microseismic activities have been detected by geophones. However, potential future commercial GCS operations from large power plants will

  4. Numerical simulation of the SAGD process coupled with geomechanical behavior

    NASA Astrophysics Data System (ADS)

    Li, Pingke

    Canada has vast oil sand resources. While a large portion of this resource can be recovered by surface mining techniques, a majority is located at depths requiring the application of in situ recovery technologies. Although a number of in situ recovery technologies exist, the steam assisted gravity drainage (SAGD) process has emerged as one of the most promising technologies to develop the in situ oil sands resources. During the SAGD operations, saturated steam is continuously injected into the oil sands reservoir, which induces pore pressure and stress variations. As a result, reservoir parameters and processes may also vary, particularly when tensile and shear failure occur. This geomechanical effect is obvious for oil sands material because oil sands have the in situ interlocked fabric. The conventional reservoir simulation generally does not take this coupled mechanism into consideration. Therefore, this research is to improve the reservoir simulation techniques of the SAGD process applied in the development of oil sands and heavy oil reservoirs. The analyses of the decoupled reservoir geomechanical simulation results show that the geomechanical behavior in SAGD has obvious impact on reservoir parameters, such as absolute permeability. The issues with the coupled reservoir geomechanical simulations of the SAGD process have been clarified and the permeability variations due to geomechanical behaviors in the SAGD process investigated. A methodology of sequentially coupled reservoir geomechanical simulation technique was developed based on the reservoir simulator, EXOTHERM, and the geomechanical simulator, FLAC. In addition, a representative geomechanical model of oil sands material was summarized in this research. Finally, this reservoir geomechanical simulation methodology was verified with the UTF Phase A SAGD project and applied in a SAGD operation with gas-over-bitumen geometry. Based on this methodology, the geomechanical effect on the SAGD production

  5. An overview of TOUGH-based geomechanics models

    DOE PAGES

    Rutqvist, Jonny

    2016-09-22

    After the initial development of the first TOUGH-based geomechanics model 15 years ago based on linking TOUGH2 multiphase flow simulator to the FLAC3D geomechanics simulator, at least 15 additional TOUGH-based geomechanics models have appeared in the literature. This development has been fueled by a growing demand and interest for modeling coupled multiphase flow and geomechanical processes related to a number of geoengineering applications, such as in geologic CO 2 sequestration, enhanced geothermal systems, unconventional hydrocarbon production, and most recently, related to reservoir stimulation and injection-induced seismicity. This paper provides a short overview of these TOUGH-based geomechanics models, focusing on somemore » of the most frequently applied to a diverse set of problems associated with geomechanics and its couplings to hydraulic, thermal and chemical processes.« less

  6. Geotechnical applications of LiDAR pertaining to geomechanical evaluation and hazard identification

    NASA Astrophysics Data System (ADS)

    Lato, Matthew J.

    respect to numerous engineering projects that are affected by geomechanical stability issues. The ability to efficiently and accurately map discontinuities, detect changes, and standardize roadside geomechanical stability analyses from remote locations will fundamentally change the state-of-practice of geotechnical investigation workflows and repeatable monitoring. This, in turn, will lead to earlier detection and definition of potential zones of instability, will allow for progressive monitoring and risk analysis, and will indicate the need for pro-active slope improvement and stabilization.

  7. Geomechanical Study of Bakken Formation for Improved Oil Recovery

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

    Ling, Kegang; Zeng, Zhengwen; He, Jun

    2013-12-31

    On October 1, 2008 US DOE-sponsored research project entitled “Geomechanical Study of Bakken Formation for Improved Oil Recovery” under agreement DE-FC26-08NT0005643 officially started at The University of North Dakota (UND). This is the final report of the project; it covers the work performed during the project period of October 1, 2008 to December 31, 2013. The objectives of this project are to outline the methodology proposed to determine the in-situ stress field and geomechanical properties of the Bakken Formation in Williston Basin, North Dakota, USA to increase the success rate of horizontal drilling and hydraulic fracturing so as to improvemore » the recovery factor of this unconventional crude oil resource from the current 3% to a higher level. The success of horizontal drilling and hydraulic fracturing depends on knowing local in-situ stress and geomechanical properties of the rocks. We propose a proactive approach to determine the in-situ stress and related geomechanical properties of the Bakken Formation in representative areas through integrated analysis of field and well data, core sample and lab experiments. Geomechanical properties are measured by AutoLab 1500 geomechanics testing system. By integrating lab testing, core observation, numerical simulation, well log and seismic image, drilling, completion, stimulation, and production data, in-situ stresses of Bakken formation are generated. These in-situ stress maps can be used as a guideline for future horizontal drilling and multi-stage fracturing design to improve the recovery of Bakken unconventional oil.« less

  8. Development of the T+M coupled flow–geomechanical simulator to describe fracture propagation and coupled flow–thermal–geomechanical processes in tight/shale gas systems

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

    Kim, Jihoon; Moridis, George J.

    2013-10-01

    We developed a hydraulic fracturing simulator by coupling a flow simulator to a geomechanics code, namely T+M simulator. Modeling of the vertical fracture development involves continuous updating of the boundary conditions and of the data connectivity, based on the finite element method for geomechanics. The T+M simulator can model the initial fracture development during the hydraulic fracturing operations, after which the domain description changes from single continuum to double or multiple continua in order to rigorously model both flow and geomechanics for fracture-rock matrix systems. The T+H simulator provides two-way coupling between fluid-heat flow and geomechanics, accounting for thermoporomechanics, treatsmore » nonlinear permeability and geomechanical moduli explicitly, and dynamically tracks changes in the fracture(s) and in the pore volume. We also fully accounts for leak-off in all directions during hydraulic fracturing. We first validate the T+M simulator, matching numerical solutions with the analytical solutions for poromechanical effects, static fractures, and fracture propagations. Then, from numerical simulation of various cases of the planar fracture propagation, shear failure can limit the vertical fracture propagation of tensile failure, because of leak-off into the reservoirs. Slow injection causes more leak-off, compared with fast injection, when the same amount of fluid is injected. Changes in initial total stress and contributions of shear effective stress to tensile failure can also affect formation of the fractured areas, and the geomechanical responses are still well-posed.« less

  9. Geomechanical Modeling for Improved CO2 Storage Security

    NASA Astrophysics Data System (ADS)

    Rutqvist, J.; Rinaldi, A. P.; Cappa, F.; Jeanne, P.; Mazzoldi, A.; Urpi, L.; Vilarrasa, V.; Guglielmi, Y.

    2017-12-01

    This presentation summarizes recent modeling studies on geomechanical aspects related to Geologic Carbon Sequestration (GCS,) including modeling potential fault reactivation, seismicity and CO2 leakage. The model simulations demonstrates that the potential for fault reactivation and the resulting seismic magnitude as well as the potential for creating a leakage path through overburden sealing layers (caprock) depends on a number of parameters such as fault orientation, stress field, and rock properties. The model simulations further demonstrate that seismic events large enough to be felt by humans requires brittle fault properties as well as continuous fault permeability allowing for the pressure to be distributed over a large fault patch to be ruptured at once. Heterogeneous fault properties, which are commonly encountered in faults intersecting multilayered shale/sandstone sequences, effectively reduce the likelihood of inducing felt seismicity and also effectively impede upward CO2 leakage. Site specific model simulations of the In Salah CO2 storage site showed that deep fractured zone responses and associated seismicity occurred in the brittle fractured sandstone reservoir, but at a very substantial reservoir overpressure close to the magnitude of the least principal stress. It is suggested that coupled geomechanical modeling be used to guide the site selection and assisting in identification of locations most prone to unwanted and damaging geomechanical changes, and to evaluate potential consequence of such unwanted geomechanical changes. The geomechanical modeling can be used to better estimate the maximum sustainable injection rate or reservoir pressure and thereby provide for improved CO2 storage security. Whether damaging geomechanical changes could actually occur very much depends on the local stress field and local reservoir properties such the presence of ductile rock and faults (which can aseismically accommodate for the stress and strain induced by

  10. Bayou Choctaw Well Integrity Grading Component Based on Geomechanical Simulation

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

    Park, Byoung

    2016-09-08

    This letter report provides a Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) well grading system based on the geomechanical simulation. The analyses described in this letter were used to evaluate the caverns’ geomechanical effect on wellbore integrity, which is an important component in the well integrity grading system recently developed by Roberts et al. [2015]. Using these analyses, the wellbores for caverns BC-17 and 20 are expected to be significantly impacted by cavern geomechanics, BC-18 and 19 are expected to be medium impacted; and the other caverns are expected to be less impacted.

  11. Testing a thermo-chemo-hydro-geomechanical model for gas hydrate-bearing sediments using triaxial compression laboratory experiments

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Deusner, C.; Haeckel, M.; Helmig, R.; Wohlmuth, B.

    2017-09-01

    Natural gas hydrates are considered a potential resource for gas production on industrial scales. Gas hydrates contribute to the strength and stiffness of the hydrate-bearing sediments. During gas production, the geomechanical stability of the sediment is compromised. Due to the potential geotechnical risks and process management issues, the mechanical behavior of the gas hydrate-bearing sediments needs to be carefully considered. In this study, we describe a coupling concept that simplifies the mathematical description of the complex interactions occurring during gas production by isolating the effects of sediment deformation and hydrate phase changes. Central to this coupling concept is the assumption that the soil grains form the load-bearing solid skeleton, while the gas hydrate enhances the mechanical properties of this skeleton. We focus on testing this coupling concept in capturing the overall impact of geomechanics on gas production behavior though numerical simulation of a high-pressure isotropic compression experiment combined with methane hydrate formation and dissociation. We consider a linear-elastic stress-strain relationship because it is uniquely defined and easy to calibrate. Since, in reality, the geomechanical response of the hydrate-bearing sediment is typically inelastic and is characterized by a significant shear-volumetric coupling, we control the experiment very carefully in order to keep the sample deformations small and well within the assumptions of poroelasticity. The closely coordinated experimental and numerical procedures enable us to validate the proposed simplified geomechanics-to-flow coupling, and set an important precursor toward enhancing our coupled hydro-geomechanical hydrate reservoir simulator with more suitable elastoplastic constitutive models.

  12. PREFACE: International Symposium on Geohazards and Geomechanics (ISGG2015)

    NASA Astrophysics Data System (ADS)

    Utili, S.

    2015-09-01

    These Conference Proceedings contain the full papers in electronic format of the International Symposium on 'Geohazards and Geomechanics', held at University of Warwick, UK, on September 10-11, 2015. The Symposium brings together the complementary expertise of world leading groups carrying out research on the engineering assessment, prevention and mitigation of geohazards. A total of 58 papers, including 8 keynote lectures cover phenomena such as landslide initiation and propagation, debris flow, rockfalls, soil liquefaction, ground improvement, hazard zonation, risk mapping, floods and gas and leachates. The techniques reported in the papers to investigate geohazards involve numerical modeling (finite element method, discrete element method, material point method, meshless methods and particle methods), experimentation (laboratory experiments, centrifuge tests and field monitoring) and analytical simplified techniques. All the contributions in this volume have been peered reviewed according to rigorous international standards. However the authors take full responsibility for the content of their papers. Agreements are in place for the edition of a special issue dedicated to the Symposium in three international journals: Engineering Geology, Computational Particle Mechanics and International Journal of Geohazards and Environment. Authors of selected papers will be invited to submit an extended version of their work to these Journals that will independently assess the papers. The Symposium is supported by the Technical Committee 'Geo-mechanics from Micro to Macro' (TC105) of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE), 'Slope Stability in Engineering Practice' (TC208), 'Forensic Geotechnical Engineering' (TC302), the British Geotechnical Association and the EU FP7 IRSES project 'Geohazards and Geomechanics'. Also the organizers would like to thank all authors and their supporting institutions for their contributions. For any

  13. Back analysis of geomechanical parameters in underground engineering using artificial bee colony.

    PubMed

    Zhu, Changxing; Zhao, Hongbo; Zhao, Ming

    2014-01-01

    Accurate geomechanical parameters are critical in tunneling excavation, design, and supporting. In this paper, a displacements back analysis based on artificial bee colony (ABC) algorithm is proposed to identify geomechanical parameters from monitored displacements. ABC was used as global optimal algorithm to search the unknown geomechanical parameters for the problem with analytical solution. To the problem without analytical solution, optimal back analysis is time-consuming, and least square support vector machine (LSSVM) was used to build the relationship between unknown geomechanical parameters and displacement and improve the efficiency of back analysis. The proposed method was applied to a tunnel with analytical solution and a tunnel without analytical solution. The results show the proposed method is feasible.

  14. Geomechanical Framework for Secure CO 2 Storage in Fractured Reservoirs and Caprocks for Sedimentary Basins in theMidwest United States

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

    Sminchak, Joel

    This report presents final technical results for the project Geomechanical Framework for Secure CO 2 Storage in Fractured Reservoirs and Caprocks for Sedimentary Basins in the Midwest United States (DE-FE0023330). The project was a three-year effort consisting of seven technical tasks focused on defining geomechanical factors for CO 2 storage applications in deep saline rock formations in Ohio and the Midwest United States, because geomechancial issues have been identified as a significant risk factor for large-scale CO 2 storage applications. A basin-scale stress-strain analysis was completed to describe the geomechanical setting for rock formations of Ordovician-Cambrian age in Ohio andmore » adjacent areas of the Midwest United States in relation to geologic CO 2 storage applications. The tectonic setting, stress orientation-magnitude, and geomechanical and petrophysical parameters for CO 2 storage zones and caprocks in the region were cataloged. Ten geophysical image logs were analyzed for natural fractures, borehole breakouts, and drilling-induced fractures. The logs indicated mostly less than 10 fractures per 100 vertical feet in the borehole, with mostly N65E principal stress orientation through the section. Geophysical image logs and other logs were obtained for three wells located near the sites where specific models were developed for geomechanical simulations: Arches site in Boone County, Kentucky; Northern Appalachian Basin site in Chautauqua County, New York; and E-Central Appalachian Basin site in Tuscarawas County, Ohio. For these three wells, 9,700 feet of image logs were processed and interpreted to provide a systematic review of the distribution within each well of natural fractures, wellbore breakouts, faults, and drilling induced fractures. There were many borehole breakouts and drilling-induced tensile fractures but few natural fractures. Concentrated fractures were present at the Rome-basal sandstone and basal sandstone-Precambrian contacts

  15. Modelling Geomechanical Heterogeneity of Rock Masses Using Direct and Indirect Geostatistical Conditional Simulation Methods

    NASA Astrophysics Data System (ADS)

    Eivazy, Hesameddin; Esmaieli, Kamran; Jean, Raynald

    2017-12-01

    An accurate characterization and modelling of rock mass geomechanical heterogeneity can lead to more efficient mine planning and design. Using deterministic approaches and random field methods for modelling rock mass heterogeneity is known to be limited in simulating the spatial variation and spatial pattern of the geomechanical properties. Although the applications of geostatistical techniques have demonstrated improvements in modelling the heterogeneity of geomechanical properties, geostatistical estimation methods such as Kriging result in estimates of geomechanical variables that are not fully representative of field observations. This paper reports on the development of 3D models for spatial variability of rock mass geomechanical properties using geostatistical conditional simulation method based on sequential Gaussian simulation. A methodology to simulate the heterogeneity of rock mass quality based on the rock mass rating is proposed and applied to a large open-pit mine in Canada. Using geomechanical core logging data collected from the mine site, a direct and an indirect approach were used to model the spatial variability of rock mass quality. The results of the two modelling approaches were validated against collected field data. The study aims to quantify the risks of pit slope failure and provides a measure of uncertainties in spatial variability of rock mass properties in different areas of the pit.

  16. Linking Geomechanical Models with Observations of Microseismicity during CCS Operations

    NASA Astrophysics Data System (ADS)

    Verdon, J.; Kendall, J.; White, D.

    2012-12-01

    During CO2 injection for the purposes of carbon capture and storage (CCS), injection-induced fracturing of the overburden represents a key risk to storage integrity. Fractures in a caprock provide a pathway along which buoyant CO2 can rise and escape the storage zone. Therefore the ability to link field-scale geomechanical models with field geophysical observations is of paramount importance to guarantee secure CO2 storage. Accurate location of microseismic events identifies where brittle failure has occurred on fracture planes. This is a manifestation of the deformation induced by CO2 injection. As the pore pressure is increased during injection, effective stress is decreased, leading to inflation of the reservoir and deformation of surrounding rocks, which creates microseismicity. The deformation induced by injection can be simulated using finite-element mechanical models. Such a model can be used to predict when and where microseismicity is expected to occur. However, typical elements in a field scale mechanical models have decameter scales, while the rupture size for microseismic events are typically of the order of 1 square meter. This means that mapping modeled stress changes to predictions of microseismic activity can be challenging. Where larger scale faults have been identified, they can be included explicitly in the geomechanical model. Where movement is simulated along these discrete features, it can be assumed that microseismicity will occur. However, microseismic events typically occur on fracture networks that are too small to be simulated explicitly in a field-scale model. Therefore, the likelihood of microseismicity occurring must be estimated within a finite element that does not contain explicitly modeled discontinuities. This can be done in a number of ways, including the utilization of measures such as closeness on the stress state to predetermined failure criteria, either for planes with a defined orientation (the Mohr-Coulomb criteria) for

  17. Development of a dynamic coupled hydro-geomechanical code and its application to induced seismicity

    NASA Astrophysics Data System (ADS)

    Miah, Md Mamun

    This research describes the importance of a hydro-geomechanical coupling in the geologic sub-surface environment from fluid injection at geothermal plants, large-scale geological CO2 sequestration for climate mitigation, enhanced oil recovery, and hydraulic fracturing during wells construction in the oil and gas industries. A sequential computational code is developed to capture the multiphysics interaction behavior by linking a flow simulation code TOUGH2 and a geomechanics modeling code PyLith. Numerical formulation of each code is discussed to demonstrate their modeling capabilities. The computational framework involves sequential coupling, and solution of two sub-problems- fluid flow through fractured and porous media and reservoir geomechanics. For each time step of flow calculation, pressure field is passed to the geomechanics code to compute effective stress field and fault slips. A simplified permeability model is implemented in the code that accounts for the permeability of porous and saturated rocks subject to confining stresses. The accuracy of the TOUGH-PyLith coupled simulator is tested by simulating Terzaghi's 1D consolidation problem. The modeling capability of coupled poroelasticity is validated by benchmarking it against Mandel's problem. The code is used to simulate both quasi-static and dynamic earthquake nucleation and slip distribution on a fault from the combined effect of far field tectonic loading and fluid injection by using an appropriate fault constitutive friction model. Results from the quasi-static induced earthquake simulations show a delayed response in earthquake nucleation. This is attributed to the increased total stress in the domain and not accounting for pressure on the fault. However, this issue is resolved in the final chapter in simulating a single event earthquake dynamic rupture. Simulation results show that fluid pressure has a positive effect on slip nucleation and subsequent crack propagation. This is confirmed by

  18. Integrated geomechanical, petrographical and petrophysical study of the sandstones of the Wajid Group, SW Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Benaafi, Mohammed; Hariri, Mustafa; Al-Shaibani, Abdulaziz; Abdullatif, Osman; Makkawi, Mohammed

    2018-07-01

    The Cambro-Permian siliciclastic succession in southwestern Saudi Arabia is represented by the Wajid Group, which consists mainly of fluvial, shallow marine, aeolian, and glacial sandstones. The Wajid Group comprises the Dibsiyah, Sanamah, Qalibah, Khusayyayn, and Juwayl Formations. It is exposed in the Wadi Al-Dawasir area and extends to Najran City. The sandstones of the Wajid Group serve as groundwater aquifers in the Wadi Al-Dawasir and Najran areas and host hydrocarbon (mainly gas) reservoirs in the Rub' Al-Khali Basin. This study aims to characterize the geomechanical properties (rock strength and Young's modulus) of the sandstones of the Wajid Group using field and experimental techniques. A further objective is to investigate the relationships between the geomechanical properties and the petrographical and petrophysical properties of the studied sandstones. The geomechanical properties of the studied sandstones vary from glacial to non-glacial sandstones, as the glacial sandstones display high values of the geomechanical properties with high variability indices. Four geological factors including grain size, cement content, porosity and permeability were observed as the main controls on the geomechanical behaviour of the studied sandstones except for the Khusayyayn sandstone, where the mineral composition was also important. Significant correlations were observed between the petrographical and petrophysical properties and the geomechanical properties of the glacial sandstones. Predictive models of the geomechanical properties (RN, UCS, and E) were generated using regression analysis to account for the glacial sandstones.

  19. Coupled hydrogeological and geomechanical modelling for the analysis of large slope instabilities.

    NASA Astrophysics Data System (ADS)

    Laloui, Lyesse; Ferrari, Alessio; Bonnard, Christophe

    2010-05-01

    Slowly-moving landslides (average velocity between 2 and 10 cm/year) are quite frequent in mountainous or hilly areas and they may display occasional crises, generally due to exceptional climatic conditions. The hazard related to these events cannot be analysed in terms of probability analysis, as the number of recorded past events is generally very small and climate changes could significantly modify the environmental setting. Quantitative relationships relating climatic condition fluctuations and sliding area velocity must then be pursued by taking into account the most relevant physical processes involved in the landslide behaviours. Conventional stability analyses are unable to deal with such questions because they do not allow the velocity fields to be determined. With regard to the behaviour of large slope instabilities, a methodology is presented which aims to describe the behaviour of slow-moving landslides by means of a coupled hydrogeological and geomechanical modelling framework. As it is well known, the evolution of the pore water pressure within the landslide body is often recognized as the main cause for the occurrence of displacement accelerations. In this sense the interaction among the hydrological and the mechanical responses must be considered to analyse the landslide behaviour, with the aim of quantitatively relating pore water pressure variations and movements. For a given case study, pore water pressure evolutions in space and time are obtained from a duly calibrated finite element hydrogeological model, which can take into account the role of several key factors such as infiltration, preferential flows and vegetation. Computed groundwater pressures resulting from the hydrogeological simulations are introduced as nodal forces in a finite element geomechanical model in order to calculate stress evolutions and displacements. The use of advanced constitutive models based on the generalised effective stress concept allows taking into account

  20. Effects of Injected CO2 on Geomechanical Properties Due to Mineralogical Changes

    NASA Astrophysics Data System (ADS)

    Nguyen, B. N.; Hou, Z.; Bacon, D. H.; Murray, C. J.; White, J. A.

    2013-12-01

    Long-term injection and storage of CO2 in deep underground reservoirs may significantly modify the geomechanical behavior of rocks since CO2 can react with the constituent phases of reservoir rocks and modify their composition. This can lead to modifications of their geomechanical properties (i.e., elastic moduli, Biot's coefficients, and permeability). Modifications of rock geomechanical properties have important consequences as these directly control stress and strain distributions, affect conditions for fracture initiation and development and/or fault healing. This paper attempts to elucidate the geochemical effects of CO2 on geomechanical properties of typical reservoir rocks by means of numerical analyses using the STOMP-ABAQUS sequentially coupled simulator that includes the capability to handle geomechanics and the reactive transport of CO2 together with a module (EMTA) to compute the homogenized rock poroelastic properties as a function of composition changes. EMTA, a software module developed at PNNL, implements the standard and advanced Eshelby-Mori-Tanaka approaches to compute the thermoelastic properties of composite materials. In this work, EMTA will be implemented in the coupled STOMP-ABAQUS simulator as a user subroutine of ABAQUS and used to compute local elastic stiffness based on rock composition. Under the STOMP-ABAQUS approach, STOMP models are built to simulate aqueous and CO2 multiphase fluid flows, and relevant chemical reactions of pore fluids with minerals in the reservoirs. The ABAQUS models then read STOMP output data for cell center coordinates, gas pressures, aqueous pressures, temperatures, saturations, constituent volume fractions, as well as permeability and porosity that are affected by chemical reactions. These data are imported into ABAQUS meshes using a mapping procedure developed for the exchange of data between STOMP and ABAQUS. Constitutive models implemented in ABAQUS via user subroutines then compute stiffness, stresses

  1. Geomechanical Simulation of Bayou Choctaw Strategic Petroleum Reserve - Model Calibration.

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

    Park, Byoung

    2017-02-01

    A finite element numerical analysis model has been constructed that consists of a realistic mesh capturing the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multi - mechanism deformation ( M - D ) salt constitutive model using the daily data of actual wellhead pressure and oil - brine interface. The salt creep rate is not uniform in the salt dome, and the creep test data for BC salt is limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the salt dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN aremore » used for the field baseline measurement. The structure factor, A 2 , and transient strain limit factor, K 0 , in the M - D constitutive model are used for the calibration. The A 2 value obtained experimentally from the BC salt and K 0 value of Waste Isolation Pilot Plant (WIPP) salt are used for the baseline values. T o adjust the magnitude of A 2 and K 0 , multiplication factors A2F and K0F are defined, respectively. The A2F and K0F values of the salt dome and salt drawdown skins surrounding each SPR cavern have been determined through a number of back fitting analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict past and future geomechanical behaviors of the salt dome, caverns, caprock , and interbed layers. The geological concerns issued in the BC site will be explained from this model in a follow - up report .« less

  2. Key Issues in Instructional Computer Graphics.

    ERIC Educational Resources Information Center

    Wozny, Michael J.

    1981-01-01

    Addresses key issues facing universities which plan to establish instructional computer graphics facilities, including computer-aided design/computer aided manufacturing systems, role in curriculum, hardware, software, writing instructional software, faculty involvement, operations, and research. Thirty-seven references and two appendices are…

  3. Key Higher-Education Issues in the States

    ERIC Educational Resources Information Center

    Fischer, Karin; Hebel, Sara

    2007-01-01

    Legislatures are set to convene in January in 43 states. This article presents the key issues that are expected to be debated by legislatures in states this year. These issues include: (1) Annulment of a controversial law in Texas that guarantees students who graduate in the top 10 percent of their high-school classes admission to any public…

  4. Geomechanical Anisotropy and Rock Fabric in Shales

    NASA Astrophysics Data System (ADS)

    Huffman, K. A.; Connolly, P.; Thornton, D. A.

    2017-12-01

    Digital rock physics (DRP) is an emerging area of qualitative and quantitative scientific analysis that has been employed on a variety of rock types at various scales to characterize petrophysical, mechanical, and hydraulic rock properties. This contribution presents a generic geomechanically focused DRP workflow involving image segmentation by geomechanical constituents, generation of finite element (FE) meshes, and application of various boundary conditions (i.e. at the edge of the domain and at boundaries of various components such as edges of individual grains). The generic workflow enables use of constituent geological objects and relationships in a computational based approach to address specific questions in a variety of rock types at various scales. Two examples are 1) modeling stress dependent permeability, where it occurs and why it occurs at the grain scale; 2) simulating the path and complexity of primary fractures and matrix damage in materials with minerals or intervals of different mechanical behavior. Geomechanical properties and fabric characterization obtained from 100 micron shale SEM images using the generic DRP workflow are presented. Image segmentation and development of FE simulation composed of relatively simple components (elastic materials, frictional contacts) and boundary conditions enable the determination of bulk static elastic properties. The procedure is repeated for co-located images at pertinent orientations to determine mechanical anisotropy. The static moduli obtained are benchmarked against lab derived measurements since material properties (esp. frictional ones) are poorly constrained at the scale of investigation. Once confidence in the input material parameters is gained, the procedure can be used to characterize more samples (i.e. images) than is possible from rock samples alone. Integration of static elastic properties with grain statistics and geologic (facies) conceptual models derived from core and geophysical logs

  5. A Computational Model of Coupled Multiphase Flow and Geomechanics to Study Fault Slip and Induced Seismicity

    NASA Astrophysics Data System (ADS)

    Juanes, R.; Jha, B.

    2014-12-01

    The coupling between subsurface flow and geomechanical deformation is critical in the assessment of the environmental impacts of groundwater use, underground liquid waste disposal, geologic storage of carbon dioxide, and exploitation of shale gas reserves. In particular, seismicity induced by fluid injection and withdrawal has emerged as a central element of the scientific discussion around subsurface technologies that tap into water and energy resources. Here we present a new computational approach to model coupled multiphase flow and geomechanics of faulted reservoirs. We represent faults as surfaces embedded in a three-dimensional medium by using zero-thickness interface elements to accurately model fault slip under dynamically evolving fluid pressure and fault strength. We incorporate the effect of fluid pressures from multiphase flow in the mechanical stability of faults and employ a rigorous formulation of nonlinear multiphase geomechanics that is capable of handling strong capillary effects. We develop a numerical simulation tool by coupling a multiphase flow simulator with a mechanics simulator, using the unconditionally stable fixed-stress scheme for the sequential solution of two-way coupling between flow and geomechanics. We validate our modeling approach using several synthetic, but realistic, test cases that illustrate the onset and evolution of earthquakes from fluid injection and withdrawal. We also present the application of the coupled flow-geomechanics simulation technology to the post mortem analysis of the Mw=5.1, May 2011 Lorca earthquake in south-east Spain, and assess the potential that the earthquake was induced by groundwater extraction.

  6. Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production

    USGS Publications Warehouse

    Rutqvist, J.; Moridis, G.J.; Grover, T.; Collett, T.

    2009-01-01

    In this simulation study, we analyzed the geomechanical response during depressurization production from two known hydrate-bearing permafrost deposits: the Mallik (Northwest Territories, Canada) deposit and Mount Elbert (Alaska, USA) deposit. Gas was produced from these deposits at constant pressure using horizontal wells placed at the top of a hydrate layer (HL), located at a depth of about 900??m at the Mallik site and 600??m at the Mount Elbert site. The simulation results show that general thermodynamic and geomechanical responses are similar for the two sites, but with substantially higher production and more intensive geomechanical responses at the deeper Mallik deposit. The depressurization-induced dissociation begins at the well bore and then spreads laterally, mainly along the top of the HL. The depressurization results in an increased shear stress within the body of the receding hydrate and causes a vertical compaction of the reservoir. However, its effects are partially mitigated by the relatively stiff permafrost overburden, and compaction of the HL is limited to less than 0.4%. The increased shear stress may lead to shear failure in the hydrate-free zone bounded by the HL overburden and the downward-receding upper dissociation interface. This zone undergoes complete hydrate dissociation, and the cohesive strength of the sediment is low. We determined that the likelihood of shear failure depends on the initial stress state as well as on the geomechanical properties of the reservoir. The Poisson's ratio of the hydrate-bearing formation is a particularly important parameter that determines whether the evolution of the reservoir stresses will increase or decrease the likelihood of shear failure.

  7. Dating Violence among College Students: Key Issues for College Counselors

    ERIC Educational Resources Information Center

    Murray, Christine E.; Kardatzke, Kerrie N.

    2007-01-01

    The authors present a review of literature examining dating violence among college students. They describe 6 key issues related to dating violence among college students that affect college counselors' work. These key issues relate to the incidence and prevalence of physical, sexual, and psychological violence in college students' dating…

  8. Three-dimensional geomechanical simulation of reservoir compaction and implications for well failures in the Belridge diatomite

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

    Fredrich, J.T.; Argueello, J.G.; Thorne, B.J.

    1996-11-01

    This paper describes an integrated geomechanics analysis of well casing damage induced by compaction of the diatomite reservoir at the Belridge Field, California. Historical data from the five field operators were compiled and analyzed to determine correlations between production, injection, subsidence, and well failures. The results of this analysis were used to develop a three-dimensional geomechanical model of South Belridge, Section 33 to examine the diatomite reservoir and overburden response to production and injection at the interwell scale and to evaluate potential well failure mechanisms. The time-dependent reservoir pressure field was derived from a three-dimensional finite difference reservoir simulation andmore » used as input to three-dimensional non-linear finite element geomechanical simulations. The reservoir simulation included -200 wells and covered 18 years of production and injection. The geomechanical simulation contained 437,100 nodes and 374,130 elements with the overburden and reservoir discretized into 13 layers with independent material properties. The results reveal the evolution of the subsurface stress and displacement fields with production and injection and suggest strategies for reducing the occurrence of well casing damage.« less

  9. Three-dimensional geomechanical simulation of reservoir compaction and implications for well failures in the Belridge diatomite

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

    Fredrich, J.T.; Argueello, J.G.; Thorne, B.J.

    1996-12-31

    This paper describes an integrated geomechanics analysis of well casing damage induced by compaction of the diatomite reservoir at the Belridge Field, California. Historical data from the five field operators were compiled and analyzed to determine correlations between production, injection, subsidence, and well failures. The results of this analysis were used to develop a three-dimensional geomechanical model of South Belridge, Section 33 to examine the diatomite reservoir and overburden response to production and injection at the interwell scale and to evaluate potential well failure mechanisms. The time-dependent reservoir pressure field was derived from a three-dimensional finite difference reservoir simulation andmore » used as input to three-dimensional non-linear finite element geomechanical simulations. The reservoir simulation included approximately 200 wells and covered 18 years of production and injection. The geomechanical simulation contained 437,100 nodes and 374,130 elements with the overburden and reservoir discretized into 13 layers with independent material properties. The results reveal the evolution of the subsurface stress and displacement fields with production and injection and suggest strategies for reducing the occurrence of well casing damage.« less

  10. Geomechanical modeling of reservoir compaction, surface subsidence, and casing damage at the Belridge diatomite field

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

    FREDRICH,JOANNE T.; DEITRICK,G.L.; ARGUELLO JR.,JOSE G.

    2000-05-01

    Geologic, and historical well failure, production, and injection data were analyzed to guide development of three-dimensional geomechanical models of the Belridge diatomite field, California. The central premise of the numerical simulations is that spatial gradients in pore pressure induced by production and injection in a low permeability reservoir may perturb the local stresses and cause subsurface deformation sufficient to result in well failure. Time-dependent reservoir pressure fields that were calculated from three-dimensional black oil reservoir simulations were coupled uni-directionally to three-dimensional non-linear finite element geomechanical simulations. The reservoir models included nearly 100,000 gridblocks (100--200 wells), and covered nearly 20 yearsmore » of production and injection. The geomechanical models were meshed from structure maps and contained more than 300,000 nodal points. Shear strain localization along weak bedding planes that causes casing dog-legs in the field was accommodated in the model by contact surfaces located immediately above the reservoir and at two locations in the overburden. The geomechanical simulations are validated by comparison of the predicted surface subsidence with field measurements, and by comparison of predicted deformation with observed casing damage. Additionally, simulations performed for two independently developed areas at South Belridge, Sections 33 and 29, corroborate their different well failure histories. The simulations suggest the three types of casing damage observed, and show that although water injection has mitigated surface subsidence, it can, under some circumstances, increase the lateral gradients in effective stress, that in turn can accelerate subsurface horizontal motions. Geomechanical simulation is an important reservoir management tool that can be used to identify optimal operating policies to mitigate casing damage for existing field developments, and applied to incorporate the

  11. Key water issues now facing our nation

    USGS Publications Warehouse

    Hirsch, Robert M.; Miller, Timothy L.; Hamilton, Pixie A.; Gilliom, Robert J.

    2008-01-01

    Challenges to sustaining sufficient and high-quality water for human consumption, industry, farms, energy production, and ecosystem services continue to intensify in many parts of the Nation. We face four key water issues that call for support from the science and engineering communities.

  12. Strategies of Educational Decentralization: Key Questions and Core Issues.

    ERIC Educational Resources Information Center

    Hanson, E. Mark

    1998-01-01

    Explains key issues and forces that shape organization and management strategies of educational decentralization, using examples from Colombia, Venezuela, Argentina, Nicaragua, and Spain. Core decentralization issues include national and regional goals, planning, political stress, resource distribution, infrastructure development, and job…

  13. Basic features of waste material storage in underground space in relation to geomechanics

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

    Konecny, P.

    1994-12-31

    It is logical to consider utilizing underground cavities for waste material disposal because, during mining, great volumes of rock materials are extracted, and underground hollow areas and communicating workings are created that can, in general, be utilized for waste disposal. Additionally, in many cases, underground waste disposal favorably supports mining process technology (for instance, application of power plant fly ash and preparation plant tailings as hardened backfill). However, it is necessary to give particular attention to the preparation, operation, and isolation of underground tip areas; errors and, in extreme cases, emergencies in underground tips are generally more difficult to dealmore » with than those in surface tips. A tip place constructed underground becomes part of the rock massif; therefore, all natural laws that rule the rock massif must be respected. Of course, such an approach requires knowledge of processes and natural regularities that will occur in rock strata where tip places have been constructed. Such knowledge is gained through familiarity with contemporary geomechanical science. The paper discusses basic geomechanical principles of underground waste disposal; geomechanical aspects of rock massif evaluation in view of waste material storage in mine workings; and plans for an experimental project for waste disposal in the Dul Ostrava underground mine.« less

  14. Arctic Freshwater Synthesis: Summary of key emerging issues

    NASA Astrophysics Data System (ADS)

    Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.; Holland, M.; Instanes, A.; Vihma, T.; Wrona, F. J.

    2015-10-01

    In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason behind the joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. The AFSΣ was structured around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources, and modeling, the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ summary manuscript reviews key issues that emerged during the conduct of the synthesis, especially those that are cross-thematic in nature, and identifies future research required to address such issues.

  15. Geochemical and Geomechanical Effects on Wellbore Cement Fractures

    DOE PAGES

    Um, Wooyong; Jung, Hun Bok; Kabilan, Senthil; ...

    2014-12-31

    Experimental studies were conducted using batch reactors, X-ray microtomograpy (XMT), and computational fluid dynamics (CFD) simulation to determine changes in cement fracture surfaces, fluid flow pathways, and permeability with geochemical and geomechanical processes. Composite Portland cement-basalt caprock core with artificial fractures was prepared and reacted with CO2-saturated groundwater at 50°C and 10 MPa for 3 to 3.5 months under static conditions to understand the geochemical and geomechanical effects on the integrity of wellbores containing defects. Cement-basalt interface samples were subjected to mechanical stress at 2.7 MPa before the CO2 reaction. XMT provided three-dimensional (3-D) visualization of the opening and interconnectionmore » of cement fractures due to mechanical stress. After the CO2 reaction, XMT images revealed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along fractures located at the cement-basalt interface. The permeability calculated based on CFD simulation was in agreement with the experimentally measured permeability. The experimental results imply that the wellbore cement with fractures is likely to be healed during exposure to CO2-saturated groundwater under static conditions, whereas fractures along the cement-caprock interface are still likely to remain vulnerable to the leakage of CO2. CFD simulation for the flow of different fluids (CO2-saturated brine and supercritical CO2) using a pressure difference of 20 kPa and 200 kPa along ~2 cm-long cement fractures showed that a pressure gradient increase resulted in an increase of CO2 fluids flux by a factor of only ~3-9 because the friction of CO2 fluids on cement fracture surfaces increased with higher flow rate as well. At the same pressure gradient, the simulated flow rate was higher for supercritical CO2 than CO2-saturated brine by a factor of only ~2-3, because the viscosity of supercritical CO2 is

  16. Shale Gas Geomechanics for Development and Performance of Unconventional Reservoirs

    NASA Astrophysics Data System (ADS)

    Domonik, Andrzej; Łukaszewski, Paweł; Wilczyński, Przemysław; Dziedzic, Artur; Łukasiak, Dominik; Bobrowska, Alicja

    2017-04-01

    Mechanical properties of individual shale formations are predominantly determined by their lithology, which reflects sedimentary facies distribution, and subsequent diagenetic and tectonic alterations. Shale rocks may exhibit complex elasto-viscoplastic deformation mechanisms depending on the rate of deformation and the amount of clay minerals, also bearing implications for subcritical crack growth and heterogeneous fracture network development. Thus, geomechanics for unconventional resources differs from conventional reservoirs due to inelastic matrix behavior, stress sensitivity, rock anisotropy and low matrix permeability. Effective horizontal drilling and hydraulic fracturing technologies are required to obtain and maintain high performance. Success of these techniques strongly depends on the geomechanical investigations of shales. An inelastic behavior of shales draws increasing attention of investigators [1], due to its role in stress relaxation between fracturing phases. A strong mechanical anisotropy in the vertical plane and a lower and more variable one in the horizontal plane are characteristic for shale rocks. The horizontal anisotropy plays an important role in determining the direction and effectiveness of propagation of technological hydraulic fractures. Non-standard rock mechanics laboratory experiments are being applied in order to obtain the mechanical properties of shales that have not been previously studied in Poland. Novel laboratory investigations were carried out to assess the creep parameters and to determine time-dependent viscoplastic deformation of shale samples, which can provide a limiting factor to tectonic stresses and control stress change caused by hydraulic fracturing. The study was supported by grant no.: 13-03-00-501-90-472946 "An integrated geomechanical investigation to enhance gas extraction from the Pomeranian shale formations", funded by the National Centre for Research and Development (NCBiR). References: Ch. Chang M. D

  17. A Novel True Triaxial Apparatus to Study the Geomechanical and Fluid Flow Aspects of Energy Exploitations in Geological Formations

    NASA Astrophysics Data System (ADS)

    Li, Minghui; Yin, Guangzhi; Xu, Jiang; Li, Wenpu; Song, Zhenlong; Jiang, Changbao

    2016-12-01

    Fluid-solid coupling investigations of the geological storage of CO2, efficient unconventional oil and natural gas exploitations are mostly conducted under conventional triaxial stress conditions ( σ 2 = σ 3), ignoring the effects of σ 2 on the geomechanical properties and permeability of rocks (shale, coal and sandstone). A novel multi-functional true triaxial geophysical (TTG) apparatus was designed, fabricated, calibrated and tested to simulate true triaxial stress ( σ 1 > σ 2 > σ 3) conditions and to reveal geomechanical properties and permeability evolutions of rocks. The apparatus was developed with the capacity to carry out geomechanical and fluid flow experiments at high three-dimensional loading forces and injection pressures under true triaxial stress conditions. The control and measurement of the fluid flow with effective sealing of rock specimen corners were achieved using a specially designed internally sealed fluid flow system. To validate that the apparatus works properly and to recognize the effects of each principal stress on rock deformation and permeability, stress-strain and permeability experiments and a hydraulic fracturing simulation experiment on shale specimens were conducted under true triaxial stress conditions using the TTG apparatus. Results show that the apparatus has advantages in recognizing the effects of σ 2 on the geomechanical properties and permeability of rocks. Results also demonstrate the effectiveness and reliability of the novel TTG apparatus. The apparatus provides a new method of studying the geomechanical properties and permeability evolutions of rocks under true triaxial stress conditions, promoting further investigations of the geological storage of CO2, efficient unconventional oil and gas exploitations.

  18. Microstructures imply cataclasis and authigenic mineral formation control geomechanical properties of New Zealand's Alpine Fault

    NASA Astrophysics Data System (ADS)

    Schuck, B.; Janssen, C.; Schleicher, A. M.; Toy, V. G.; Dresen, G.

    2018-05-01

    The Alpine Fault is capable of generating large (MW > 8) earthquakes and is the main geohazard on South Island, NZ, and late in its 250-291-year seismic cycle. To minimize its hazard potential, it is indispensable to identify and understand the processes influencing the geomechanical behavior and strength-evolution of the fault. High-resolution microstructural, mineralogical and geochemical analyses of the Alpine Fault's core demonstrate wall rock fragmentation, assisted by mineral dissolution, and cementation resulting in the formation of a fine-grained principal slip zone (PSZ). A complex network of anastomosing and mutually cross-cutting calcite veins implies that faulting occurred during episodes of dilation, slip and sealing. Fluid-assisted dilatancy leads to a significant volume increase accommodated by vein formation in the fault core. Undeformed euhedral chlorite crystals and calcite veins that have cut footwall gravels demonstrate that these processes occurred very close to the Earth's surface. Microstructural evidence indicates that cataclastic processes dominate the deformation and we suggest that powder lubrication and grain rolling, particularly influenced by abundant nanoparticles, play a key role in the fault core's velocity-weakening behavior rather than frictional sliding. This is further supported by the absence of smectite, which is reasonable given recently measured geothermal gradients of more than 120 °C km-1 and the impermeable nature of the PSZ, which both limit the growth of this phase and restrict its stability to shallow depths. Our observations demonstrate that high-temperature fluids can influence authigenic mineral formation and thus control the fault's geomechanical behavior and the cyclic evolution of its strength.

  19. Workplace wellness programs in Canada: an exploration of key issues.

    PubMed

    Morrison, Erin; MacKinnon, Neil J

    2008-01-01

    Faced with the reality of rising health costs, Canadian employers are thinking beyond traditional notions of responsibility for employee health and have begun to embrace Workplace Wellness Programs (WWPs). This article investigates the critical issues of WWPs in the Canadian context from the perspective of key stakeholders. Using a combination of literature and key informant interviews, seven key themes are presented along with recommendations for wider implementation of WWPs in Canada.

  20. Geomechanical Modeling of Deformation Banding in the Navajo Sandstone, San Rafael Monocline, Utah

    NASA Astrophysics Data System (ADS)

    Gutierrez, M.; Sundal, A.; Petrie, E. S.

    2017-12-01

    Deformation bands are ubiquitous geological features in many types of rocks. Depending on their micro-structure, they can act either as conduits or barriers to fluid flow. Given the significant roles deformation bands play in fluid flow and chemical transport in rocks, it is important to develop fundamental understanding of their origin, and their characteristics as they relate with the host rock properties and their depositional and structural-geological history. We present a forward-modeling technique based on the geomechanical Bifurcation Theory (BT) to predict the formation of deformation bands in sandstone. According to BT, the formation of deformation bands is a result of strain location, which in turn stems from instability in the stress-strain response of materials during loading. Due to bifurcation, a material which undergoes homogeneous deformation can reach a point at which the material experiences instability and deformation starts to become non-homogenous. We implemented BT in the commercially-available geomechanical code FLAC (Fast Langragian Analysis of Continua) and applied it in the field-scale modeling of deformation banding in the Navajo Sandstone in the San Rafael Monocline in Utah induced by fault propagation folding. The results show that geomechanical modeling using BT has a powerful potential to simulate the physical processes in the formation of deformation banding in rocks. Predicted deformation bands, specifically the pervasive bedding-parallel bands in the Navajo sandstone formation, normal faulting in the upper limb and reverse faulting in the lower limb, are generally in agreement with field observations. Predictions indicate that the pervasive bedding-parallel bands in the Navajo Sandstone are transitional compaction-shear bands with alternating zones of volumetric compaction and dilation. These predictions are consistent with petrographic analysis of thin sections of rock samples from the Navajo Sandstone. The most important

  1. User's Guide of TOUGH2-EGS. A Coupled Geomechanical and Reactive Geochemical Simulator for Fluid and Heat Flow in Enhanced Geothermal Systems Version 1.0

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

    Fakcharoenphol, Perapon; Xiong, Yi; Hu, Litang

    TOUGH2-EGS is a numerical simulation program coupling geomechanics and chemical reactions for fluid and heat flows in porous media and fractured reservoirs of enhanced geothermal systems. The simulator includes the fully-coupled geomechanical (THM) module, the fully-coupled geochemical (THC) module, and the sequentially coupled reactive geochemistry (THMC) module. The fully-coupled flow-geomechanics model is developed from the linear elastic theory for the thermo-poro-elastic system and is formulated with the mean normal stress as well as pore pressure and temperature. The chemical reaction is sequentially coupled after solution of flow equations, which provides the flow velocity and phase saturation for the solute transportmore » calculation at each time step. In addition, reservoir rock properties, such as porosity and permeability, are subjected to change due to rock deformation and chemical reactions. The relationships between rock properties and geomechanical and chemical effects from poro-elasticity theories and empirical correlations are incorporated into the simulator. This report provides the user with detailed information on both mathematical models and instructions for using TOUGH2-EGS for THM, THC or THMC simulations. The mathematical models include the fluid and heat flow equations, geomechanical equation, reactive geochemistry equations, and discretization methods. Although TOUGH2-EGS has the capability for simulating fluid and heat flows coupled with both geomechanical and chemical effects, it is up to the users to select the specific coupling process, such as THM, THC, or THMC in a simulation. There are several example problems illustrating the applications of this program. These example problems are described in details and their input data are presented. The results demonstrate that this program can be used for field-scale geothermal reservoir simulation with fluid and heat flow, geomechanical effect, and chemical reaction in porous and

  2. Analyzing a suitable elastic geomechanical model for Vaca Muerta Formation

    NASA Astrophysics Data System (ADS)

    Sosa Massaro, Agustin; Espinoza, D. Nicolas; Frydman, Marcelo; Barredo, Silvia; Cuervo, Sergio

    2017-11-01

    Accurate geomechanical evaluation of oil and gas reservoir rocks is important to provide design parameters for drilling, completion and predict production rates. In particular, shale reservoir rocks are geologically complex and heterogeneous. Wells need to be hydraulically fractured for stimulation and, in complex tectonic environments, it is to consider that rock fabric and in situ stress, strongly influence fracture propagation geometry. This article presents a combined wellbore-laboratory characterization of the geomechanical properties of a well in El Trapial/Curamched Field, over the Vaca Muerta Formation, located in the Neuquén Basin in Argentina. The study shows the results of triaxial tests with acoustic measurements in rock plugs from outcrops and field cores, and corresponding dynamic to static correlations considering various elastic models. The models, with increasing complexity, include the Isotropic Elastic Model (IEM), the Anisotropic Elastic Model (AEM) and the Detailed Anisotropic Elastic Model (DAEM). Each model shows advantages over the others. An IEM offers a quick overview, being easy to run without much detailed data for heterogeneous and anisotropic rocks. The DAEM requires significant amounts of data, time and a multidisciplinary team to arrive to a detailed model. Finally, an AEM suits well to an anisotropic and realistic rock without the need of massive amounts of data.

  3. Faults simulations for three-dimensional reservoir-geomechanical models with the extended finite element method

    NASA Astrophysics Data System (ADS)

    Prévost, Jean H.; Sukumar, N.

    2016-01-01

    Faults are geological entities with thicknesses several orders of magnitude smaller than the grid blocks typically used to discretize reservoir and/or over-under-burden geological formations. Introducing faults in a complex reservoir and/or geomechanical mesh therefore poses significant meshing difficulties. In this paper, we consider the strong-coupling of solid displacement and fluid pressure in a three-dimensional poro-mechanical (reservoir-geomechanical) model. We introduce faults in the mesh without meshing them explicitly, by using the extended finite element method (X-FEM) in which the nodes whose basis function support intersects the fault are enriched within the framework of partition of unity. For the geomechanics, the fault is treated as an internal displacement discontinuity that allows slipping to occur using a Mohr-Coulomb type criterion. For the reservoir, the fault is either an internal fluid flow conduit that allows fluid flow in the fault as well as to enter/leave the fault or is a barrier to flow (sealing fault). For internal fluid flow conduits, the continuous fluid pressure approximation admits a discontinuity in its normal derivative across the fault, whereas for an impermeable fault, the pressure approximation is discontinuous across the fault. Equal-order displacement and pressure approximations are used. Two- and three-dimensional benchmark computations are presented to verify the accuracy of the approach, and simulations are presented that reveal the influence of the rate of loading on the activation of faults.

  4. Geomechanical Characterization and Stability Analysis of the Bedrock Underlying the Costa Concordia Cruise Ship

    NASA Astrophysics Data System (ADS)

    Dotta, Giulia; Gigli, Giovanni; Ferrigno, Federica; Gabbani, Giuliano; Nocentini, Massimiliano; Lombardi, Luca; Agostini, Andrea; Nolesini, Teresa; Casagli, Nicola

    2017-09-01

    The shipwreck of the Costa Concordia cruise ship, which ran aground on 13 January 2012 on the northwestern coast of Giglio Island (Italy), required continuous monitoring of the position and movement of the vessel to guarantee the security of workers and rescuers operating around and within the wreck and to support shipwreck removal operations. Furthermore, understanding the geomechanical properties and stability behaviour of the coastal rock mass and rocky seabed underlying the ship was of similar importance. To assess the stability conditions of the ship, a ground-based monitoring system was installed in front of the wreck. The network included a terrestrial laser scanner (TLS) device, which was used to perform remote semiautomatic geomechanical characterization of the observed rock mass. Using TLS survey techniques, three main discontinuity sets were identified in the granitic rock mass of Giglio Island. Furthermore, a multibeam bathymetric survey was used to qualitatively characterize the seabed. To integrate the processed TLS data and quantitatively describe the rock mass quality, a subsequent field survey was carried out to provide a rock mass geomechanical evaluation (from very good to moderate quality). Based on the acquired information, kinematic and stability analyses were performed to create a spatial prediction of rock failure mechanisms in the study area. The obtained kinematic hazard index values were generally low; only the plane failure index reached slightly higher values. The general stability of the rock mass was confirmed by the stability analysis, which yielded a high safety factor value (approximately 12).

  5. Task-Based Pronunciation Teaching and Research: Key Issues and Future Directions

    ERIC Educational Resources Information Center

    Mora, Joan C.; Levkina, Mayya

    2017-01-01

    This article synthesizes the conclusions of the empirical studies in this special issue and outlines key questions in future research. The research reported in this volume has identified several fundamental issues in pronunciation-focused task design that are discussed in detail and on which suggestions for further research are outlined. One…

  6. Geomechanical Modeling of Gas Hydrate Bearing Sediments

    NASA Astrophysics Data System (ADS)

    Sanchez, M. J.; Gai, X., Sr.

    2015-12-01

    This contribution focuses on an advance geomechanical model for methane hydrate-bearing soils based on concepts of elasto-plasticity for strain hardening/softening soils and incorporates bonding and damage effects. The core of the proposed model includes: a hierarchical single surface critical state framework, sub-loading concepts for modeling the plastic strains generally observed inside the yield surface and a hydrate enhancement factor to account for the cementing effects provided by the presence of hydrates in sediments. The proposed framework has been validated against recently published experiments involving both, synthetic and natural hydrate soils, as well as different sediments types (i.e., different hydrate saturations, and different hydrates morphologies) and confinement conditions. The performance of the model in these different case studies was very satisfactory.

  7. Quantifying the Impact of Additional Laboratory Tests on the Quality of a Geomechanical Model

    NASA Astrophysics Data System (ADS)

    Fillion, Marie-Hélène; Hadjigeorgiou, John

    2017-05-01

    In an open-pit mine operation, the design of safe and economically viable slopes can be significantly influenced by the quality and quantity of collected geomechanical data. In several mining jurisdictions, codes and standards are available for reporting exploration data, but similar codes or guidelines are not formally available or enforced for geotechnical design. Current recommendations suggest a target level of confidence in the rock mass properties used for slope design. As these guidelines are qualitative and somewhat subjective, questions arise regarding the minimum number of tests to perform in order to reach the proposed level of confidence. This paper investigates the impact of defining a priori the required number of laboratory tests to conduct on rock core samples based on the geomechanical database of an operating open-pit mine in South Africa. In this review, to illustrate the process, the focus is on uniaxial compressive strength properties. Available strength data for 2 project stages were analysed using the small-sampling theory and the confidence interval approach. The results showed that the number of specimens was too low to obtain a reliable strength value for some geotechnical domains even if more specimens than the minimum proposed by the ISRM suggested methods were tested. Furthermore, the testing sequence used has an impact on the minimum number of specimens required. Current best practice cannot capture all possibilities regarding the geomechanical property distributions, and there is a demonstrated need for a method to determine the minimum number of specimens required while minimising the influence of the testing sequence.

  8. Teacher-Student Sexual Relations: Key Risks and Ethical Issues

    ERIC Educational Resources Information Center

    Sikes, Pat

    2010-01-01

    Researching actual or purported sexual contact between teachers and students raises many difficult ethical issues, questions and dilemmas, which may help to explain why few have ventured into the field. This experientially based paper addresses key problem areas under the headings of: the ethics of researching a sensitive taboo topic; the ethics…

  9. Investigation of intact rock geomechanical parameters' effects on commercial blocks' productivity within stone reserves: A case history of some quarries in Isfahan, Iran

    NASA Astrophysics Data System (ADS)

    Yarahmadi, Reza; Bagherpour, Raheb; Tabaei, Morteza; Sousa, Luis M. O.

    2017-10-01

    One of the common methods to determine commercial blocks productivity (CBP) in reserves of dimension stone is through the study of the discontinuities' network. However, this determination remains a difficult task due to geographical heterogeneity and lack of access to all reserves' formations. This study presents a new method based on various geomechanical tests performed on intact rocks that assessed the CBP of a dimension stones' rock mass. Assuming that a dimension stone's rock mass comprised a large block of an intact rock, due to tectonics, the geomechanical properties of this block had direct effects on the discontinuities created within it. Therefore, the geomechanical properties of the intact rock may be related to the CBP of a stone reserve. Based on this factor, this study explored the relationship among some geomechanical properties, including failure angle, uniaxial compressive strength, and modulus of elasticity, and CBP by using data acquired from 21 dimension stone quarries consisting of travertine, marble, and onyx groups. According to the results obtained from the analysis of the Isfahan province's Iranian quarries, failure angle was not highly related to the reserve's CBP. In marble quarries, CBP may decrease, if the compressive strength of an intact rock exceeds 60 MPa. Among the studied parameters, the saturated-to-dry ratio's modulus of elasticity had the greatest relationship to the CBP. Generally, the presented diagrams displayed that the correlation between geomechanical properties and the CBP were an appropriate guide in determining the potential cost-effectiveness of a accessing a particular rock reserve during the early exploration phase.

  10. Key issues in the quality assurance of the One Number Census.

    PubMed

    Diamond, Ian; Abbott, Owen; Jackson, Neil

    2003-01-01

    As part of the 2001 Census, the One Number Census project estimated and adjusted the Census database for underenumeration. As a result of the highly innovative One Number Census and the Quality Assurance process it encompassed, it was also ensured that robust results could be obtained for each local authority area. This article examines some of the issues and analyses that were undertaken as part of that assessment of the 2001 Census population counts for England and Wales. The article firstly highlights the key issues surrounding the implementation of the 2001 Census fieldwork. The article then explores the 2001 Census results through a series of demographic analyses to illustrate the sorts of issues investigated during the One Number Census Quality Assurance process itself. These analyses look at the patterns contained within the results, and comparisons with key alternative sources of population counts. Overall, these in-depth analyses and investigations provide further credence to the plausibility of the One Number Census results.

  11. Fabric symmetry of low anisotropic rocks inferred from ultrasonic sounding: Implications for the geomechanical models

    NASA Astrophysics Data System (ADS)

    Přikryl, Richard; Lokajíček, Tomáš; Pros, Zdeněk; Klíma, Karel

    2007-02-01

    The geomechanical models were established based on the absence or presence of certain rock fabric elements — texture (crystallographic preferred orientation), microstructure (shape preferred orientation) and microcracks (flat voids). The proposed models include both (i) the ideal material showing random texture and structure but no microcracks, i.e. the material which is hardly to be found in nature, and (ii) the materials possessing various combinations of fabric elements that show different spatial arrangements. The mutual relationship between those parameters and seismic and geomechanical properties are discussed. Selected models were experimentally verified during laboratory experiments. These consist of measurement of P-wave velocities in 132 independent directions under several confining pressures in the range 0.1-400 MPa. From measured data 3D P-wave patterns can be constructed and the influence of microcracks and of texture and structure on the rock seismic anisotropy can be determined. The seismic anisotropy established at different levels of confining pressure can be used for the interpretation of rock fabric symmetry of rocks showing low anisotropy in macroscale and for the selection of directions in which the geomechanical test can be performed. The measured P-wave velocities were then mathematically processed by using a fitting function V=V+k·P-v·10 which reflects contribution of P-wave velocity in the mineral skeleton of an ideal sample without microcracks extrapolated to the atmospheric pressure level from high confining pressure interval (ca. 200-400 MPa) ( v0), linear compressibility of the samples ( kv), and confining pressure during which most of the cracks are closed ( P0). These parameters improve the understanding of the response of various rock fabric elements on increasing confinement and corresponding changes in elasticity. The observed seismic and geomechanical anisotropies reflect intensity of the fabric of rock-forming minerals and

  12. Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight- and Shale-Gas Reservoirs: Material Failure and Enhanced Permeability

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

    Kim, Jihoon; Moridis, George J.

    We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gasmore » causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design

  13. Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight- and Shale-Gas Reservoirs: Material Failure and Enhanced Permeability

    DOE PAGES

    Kim, Jihoon; Moridis, George J.

    2014-12-01

    We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gasmore » causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design

  14. Human Health Effects of Biphenyl: Key Findings and Scientific Issues

    PubMed Central

    Li, Zheng; Hogan, Karen A.; Cai, Christine; Rieth, Susan

    2015-01-01

    Background: In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) has evaluated the human health hazards of biphenyl exposure. Objectives: We review key findings and scientific issues regarding expected human health effects of biphenyl. Methods: Scientific literature from 1926 through September 2012 was critically evaluated to identify potential human health hazards associated with biphenyl exposure. Key issues related to the carcinogenicity and noncancer health hazards of biphenyl were examined based on evidence from experimental animal bioassays and mechanistic studies. Discussion: Systematic consideration of experimental animal studies of oral biphenyl exposure took into account the variety of study designs (e.g., study sizes, exposure levels, and exposure durations) to reconcile differing reported results. The available mechanistic and toxicokinetic evidence supports the hypothesis that male rat urinary bladder tumors arise through urinary bladder calculi formation but is insufficient to hypothesize a mode of action for liver tumors in female mice. Biphenyl and its metabolites may induce genetic damage, but a role for genotoxicity in biphenyl-induced carcinogenicity has not been established. Conclusions: The available health effects data for biphenyl provides suggestive evidence for carcinogenicity in humans, based on increased incidences of male rat urinary bladder tumors at high exposure levels and on female mouse liver tumors. Kidney toxicity is also a potential human health hazard of biphenyl exposure. Citation: Li Z, Hogan KA, Cai C, Rieth S. 2016. Human health effects of biphenyl: key findings and scientific issues. Environ Health Perspect 124:703–712; http://dx.doi.org/10.1289/ehp.1509730 PMID:26529796

  15. Human Health Effects of Biphenyl: Key Findings and Scientific Issues.

    PubMed

    Li, Zheng; Hogan, Karen A; Cai, Christine; Rieth, Susan

    2016-06-01

    In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) has evaluated the human health hazards of biphenyl exposure. We review key findings and scientific issues regarding expected human health effects of biphenyl. Scientific literature from 1926 through September 2012 was critically evaluated to identify potential human health hazards associated with biphenyl exposure. Key issues related to the carcinogenicity and noncancer health hazards of biphenyl were examined based on evidence from experimental animal bioassays and mechanistic studies. Systematic consideration of experimental animal studies of oral biphenyl exposure took into account the variety of study designs (e.g., study sizes, exposure levels, and exposure durations) to reconcile differing reported results. The available mechanistic and toxicokinetic evidence supports the hypothesis that male rat urinary bladder tumors arise through urinary bladder calculi formation but is insufficient to hypothesize a mode of action for liver tumors in female mice. Biphenyl and its metabolites may induce genetic damage, but a role for genotoxicity in biphenyl-induced carcinogenicity has not been established. The available health effects data for biphenyl provides suggestive evidence for carcinogenicity in humans, based on increased incidences of male rat urinary bladder tumors at high exposure levels and on female mouse liver tumors. Kidney toxicity is also a potential human health hazard of biphenyl exposure. Li Z, Hogan KA, Cai C, Rieth S. 2016. Human health effects of biphenyl: key findings and scientific issues. Environ Health Perspect 124:703-712; http://dx.doi.org/10.1289/ehp.1509730.

  16. Wildfire in the United Kingdom: status and key issues

    Treesearch

    Julia McMorrow

    2011-01-01

    This paper reviews the status of wildfire risk in the United Kingdom and examines some of the key issues in U.K. wildfire management. Wildfires challenge the resources of U.K. Fire and Rescue Services (FRSs), especially in dry years, yet FRSs are poorly equipped and trained to deal with wildfire. A brief geography of U.K. wildfires is presented using fire statistics...

  17. The balancing act: key issues in the lives of women general practitioners in Australia.

    PubMed

    Kilmartin, Margaret R; Newell, Christopher J; Line, Martin A

    2002-07-15

    To identify key issues affecting women general practitioners in their professional and non-professional lives. A qualitative study using the Delphi technique, with three rounds of data provision circulated to each participant. Coding was used to ensure anonymity. The participants were a purposive sample of 40 women GPs drawn from all Australian States and Territories. The study was conducted between October 1996 and January 1997. Key issues affecting the professional and non-professional lives of women GPs. Some of the key professional issues for women GPs were job satisfaction, balancing work and personal life, autonomy, availability of flexible and part-time work and training, affordability of professional expenses, fair remuneration, and having a voice in decision-making. Key non-professional issues included self-care; time for relationships with a partner, children, family and friends; and time management to allow pursuit of non-medical interests. The conflicting demands made on women GPs diminish their job satisfaction and lead to stress and imbalance in their lives. Recommendations to ameliorate the problems for women GPs include appropriate training, policy formation, financial and other support, and a change in cultural expectations of women GPs by the community, the profession and governments.

  18. NCAP projection displays: key issues for commercialization

    NASA Astrophysics Data System (ADS)

    Tomita, Akira; Jones, Philip J.

    1992-06-01

    Recently there has been much interest in a new polymer nematic dispersion technology, often called as NCAP, PDLC, PNLC, LCPC, etc., since projection displays using this technology have been shown to produce much brighter display images than projectors using conventional twisted nematic (TN) lightvalves. For commercializing projection displays based on this polymer nematic dispersion technology, the new materials must not only meet various electro- optic requirements, e.g., operational voltage, `off-state'' scattering angle, voltage holding ratio and hysteresis, but must also be stable over the lifetime of the product. This paper reports recent progress in the development of NCAP based projection displays and discusses some of the key commercialization issues.

  19. Impact of hydrogeological and geomechanical properties on surface uplift at a CO2 injection site: Parameter estimation and uncertainty quantification

    NASA Astrophysics Data System (ADS)

    Newell, P.; Yoon, H.; Martinez, M. J.; Bishop, J. E.; Arnold, B. W.; Bryant, S.

    2013-12-01

    It is essential to couple multiphase flow and geomechanical response in order to predict a consequence of geological storage of CO2. In this study, we estimate key hydrogeologic features to govern the geomechanical response (i.e., surface uplift) at a large-scale CO2 injection project at In Salah, Algeria using the Sierra Toolkit - a multi-physics simulation code developed at Sandia National Laboratories. Importantly, a jointed rock model is used to study the effect of postulated fractures in the injection zone on the surface uplift. The In Salah Gas Project includes an industrial-scale demonstration of CO2 storage in an active gas field where CO2 from natural gas production is being re-injected into a brine-filled portion of the structure downdip of the gas accumulation. The observed data include millimeter scale surface deformations (e.g., uplift) reported in the literature and injection well locations and rate histories provided by the operators. Our preliminary results show that the intrinsic permeability and Biot coefficient of the injection zone are important. Moreover pre-existing fractures within the injection zone affect the uplift significantly. Estimation of additional (i.e., anisotropy ratio) and coupled parameters will help us to develop models, which account for the complex relationship between mechanical integrity and CO2 injection-induced pressure changes. Uncertainty quantification of model predictions will be also performed using various algorithms including null-space Monte Carlo and polynomial-chaos expansion methods. This work will highlight that our coupled reservoir and geomechanical simulations associated with parameter estimation can provide a practical solution for designing operating conditions and understanding subsurface processes associated with the CO2 injection. This work is supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office

  20. Role of geomechanically grown fractures on dispersive transport in heterogeneous geological formations.

    PubMed

    Nick, H M; Paluszny, A; Blunt, M J; Matthai, S K

    2011-11-01

    A second order in space accurate implicit scheme for time-dependent advection-dispersion equations and a discrete fracture propagation model are employed to model solute transport in porous media. We study the impact of the fractures on mass transport and dispersion. To model flow and transport, pressure and transport equations are integrated using a finite-element, node-centered finite-volume approach. Fracture geometries are incrementally developed from a random distributions of material flaws using an adoptive geomechanical finite-element model that also produces fracture aperture distributions. This quasistatic propagation assumes a linear elastic rock matrix, and crack propagation is governed by a subcritical crack growth failure criterion. Fracture propagation, intersection, and closure are handled geometrically. The flow and transport simulations are separately conducted for a range of fracture densities that are generated by the geomechanical finite-element model. These computations show that the most influential parameters for solute transport in fractured porous media are as follows: fracture density and fracture-matrix flux ratio that is influenced by matrix permeability. Using an equivalent fracture aperture size, computed on the basis of equivalent permeability of the system, we also obtain an acceptable prediction of the macrodispersion of poorly interconnected fracture networks. The results hold for fractures at relatively low density.

  1. Mixed Methods Research: What Are the Key Issues to Consider?

    ERIC Educational Resources Information Center

    Ghosh, Rajashi

    2016-01-01

    Mixed methods research (MMR) is increasingly becoming a popular methodological approach in several fields due to the promise it holds for comprehensive understanding of complex problems being researched. However, researchers interested in MMR often lack reference to a guide that can explain the key issues pertaining to the paradigm wars…

  2. Social Work Practice with Latinos: Key Issues for Social Workers

    ERIC Educational Resources Information Center

    Furman, Rich; Negi, Nalini Junko; Iwamoto, Derek Kenji; Rowan, Diana; Shukraft, Allison; Gragg, Jennifer

    2009-01-01

    The Latino population is the fastest growing group in the United States; thus, it is imperative that social workers and other mental health practitioners be knowledgeable about the current literature on how to effectively serve this population. This article elucidates key issues and knowledge, such as immigration and migration concerns; discusses…

  3. Effects of Geomechanical Mechanism on the Gas Production Behavior: A Simulation Study of Class-3 Type Four-Way-Closure Ridge Hydrate Deposit Offshore Southwestern Taiwan

    NASA Astrophysics Data System (ADS)

    Wu, Cheng-Yueh; Chiu, Yung-Cheng; Huang, Yi-Jyun; Hsieh, Bieng-Zih

    2017-04-01

    The future energy police of Taiwan will heavily rely on the clean energy, including renewable energy and low-carbon energy, to meet the target of mitigating CO2 emission. In addition to developing the renewable energies like solar and wind resources, Taiwan will increase the natural gas consumption to obtain enough electrical power with low-carbon emission. The vast resources of gas hydrates recognized in southwestern offshore Taiwan makes a great opportunity for Taiwan to have own energy resources in the future. Therefore, Taiwan put significant efforts on the evaluation of gas hydrate reserves recently. Production behavior of natural gas dissociated from gas hydrate deposits is an important issue to the hydrate reserves evaluation. The depressurization method is a useful engineering recovery method for gas production from a class-3 type hydrate deposit. The dissociation efficiency will be affected by the pressure drawdown disturbance. However, when the pore pressure of hydrate deposits is depressurized for gas production, the rock matrix will surfer more stresses and the formation deformation might be occurred. The purpose of this study was to investigate the effects of geomechanical mechanism on the gas production from a class-3 hydrate deposit using depressurization method. The case of a class-3 type hydrate deposit of Four-Way-Closure Ridge was studied. In this study a reservoir simulator, STARS, was used. STARS is a multiphase flow, heat transfer, geo-chemical and geo-mechanical mechanisms coupling simulator which is capable to simulate the dissociation/reformation of gas hydrate and the deformation of hydrate reservoirs and overburdens. The simulating ability of STARTS simulator was validated by duplicating the hydrate comparison projects of National Energy Technology Lab. The study target, Four-Way-Closure (FWC) Ridge hydrate deposit, was discovered by the bottom simulating reflectors (BSRs). The geological parameters were collected from the geological and

  4. Coupled multiphase flow and geomechanics analysis of the 2011 Lorca earthquake

    NASA Astrophysics Data System (ADS)

    Jha, B.; Hager, B. H.; Juanes, R.; Bechor, N.

    2013-12-01

    We present a new approach for modeling coupled multiphase flow and geomechanics of faulted reservoirs. We couple a flow simulator with a mechanics simulator using the unconditionally stable fixed-stress sequential solution scheme [Kim et al, 2011]. We model faults as surfaces of discontinuity using interface elements [Aagaard et al, 2008]. This allows us to model stick-slip behavior on the fault surface for dynamically evolving fault strength. We employ a rigorous formulation of nonlinear multiphase geomechanics [Coussy, 1995], which is based on the increment in mass of fluid phases instead of the traditional, and less accurate, scheme based on the change in porosity. Our nonlinear formulation is capable of handling strong capillarity and large changes in saturation in the reservoir. To account for the effect of surface stresses along fluid-fluid interfaces, we use the equivalent pore pressure in the definition of the multiphase effective stress [Coussy et al, 1998; Kim et al, 2013]. We use our simulation tool to study the 2011 Lorca earthquake [Gonzalez et al, 2012], which has received much attention because of its potential anthropogenic triggering (long-term groundwater withdrawal leading to slip along the regional Alhama de Murcia fault). Our coupled fluid flow and geomechanics approach to model fault slip allowed us to take a fresh look at this seismic event, which to date has only been analyzed using simple elastic dislocation models and point source solutions. Using a three-dimensional model of the Lorca region, we simulate the groundwater withdrawal and subsequent unloading of the basin over the period of interest (1960-2010). We find that groundwater withdrawal leads to unloading of the crust and changes in the stress across the impermeable fault plane. Our analysis suggests that the combination of these two factors played a critical role in inducing the fault slip that ultimately led to the Lorca earthquake. Aagaard, B. T., M. G. Knepley, and C. A

  5. The geomechanical strength of carbonate rock in Kinta valley, Ipoh, Perak Malaysia

    NASA Astrophysics Data System (ADS)

    Mazlan, Nur Amanina; Lai, Goh Thian; Razib, Ainul Mardhiyah Mohd; Rafek, Abdul Ghani; Serasa, Ailie Sofyiana; Simon, Norbert; Surip, Noraini; Ern, Lee Khai; Mohamed, Tuan Rusli

    2018-04-01

    The stability of both cut rocks and underground openings were influenced by the geomechanical strength of rock materials, while the strength characteristics are influenced by both material characteristics and the condition of weathering. This paper present a systematic approach to quantify the rock material strength characteristics for material failure and material & discontinuities failure by using uniaxial compressive strength, point load strength index and Brazilian tensile strength for carbonate rocks. Statistical analysis of the results at 95 percent confidence level showed that the mean value of compressive strength, point load strength index and Brazilian tensile strength for with material failure and material & discontinuities failure were 76.8 ± 4.5 and 41.2 ± 4.1 MPa with standard deviation of 15.2 and 6.5 MPa, respectively. The point load strength index for material failure and material & discontinuities failure were 3.1 ± 0.2 MPa and 1.8 ± 0.3 MPa with standard deviation of 0.9 and 0.6 MPa, respectively. The Brazilian tensile strength with material failure and material & discontinuities failure were 7.1 ± 0.3 MPa and 4.1 ± 0.3 MPa with standard deviation of 1.4 and 0.6 MPa, respectively. The results of this research revealed that the geomechanical strengths of rock material of carbonate rocks for material & discontinuities failure deteriorates approximately ½ from material failure.

  6. Key Policy Issues in the Implementation of User Choice. Working Paper No. 8.

    ERIC Educational Resources Information Center

    Smith, Joy Selby; Smith, Chris Selby; Ferrier, Fran

    This working paper examines key policy issues in the implementation of Australia's User Choice policy regarding allocating public funds for vocational education and training (VET). Part 1 explains the process used to obtain stakeholders regarding the User Choice policy, the administrative arrangements required to support it, and issues that must…

  7. Social Work Practice with Latinos: Key Issues for Social Workers

    PubMed Central

    Furman, Rich; Negi, Nalini Junko; Iwamoto, Derek Kenji; Rowan, Diana; Shukraft, Allison; Gragg, Jennifer

    2010-01-01

    The Latino population is the fastest growing group in the United States; thus, it is imperative that social workers and other mental health practitioners be knowledgeable about the current literature on how to effectively serve this population. This article elucidates key issues and knowledge, such as immigration and migration concerns; discusses how to assess for levels of acculturation; examines cultural values; and highlights salient work issues and health disparities that Latinos experience. Recommendations on how agencies and universities can recruit and promote bilingual practitioners are introduced. Finally, culturally responsive strategies for professional use of self and fostering the therapeutic alliance are discussed. PMID:19366165

  8. Key Issues in Hymenoptera Venom Allergy: An Update.

    PubMed

    Alfaya Arias, T; Soriano Gómis, V; Soto Mera, T; Vega Castro, A; Vega Gutiérrez, J M; Alonso Llamazares, A; Antolín Amérigo, D; Carballada Gonzalez, F J; Dominguez Noche, C; Gutierrez Fernandez, D; Marques Amat, L; Martinez Arcediano, A; Martinez San Ireneo, M; Moreno Ancillo, A; Puente Crespo, Y; Ruiz Leon, B; Sánchez Morillas, L

    In this review, the Hymenoptera Allergy Committee of the SEAIC analyzes the most recent scientific literature addressing problems related to the diagnosis of hymenoptera allergy and to management of venom immunotherapy. Molecular diagnosis and molecular risk profiles are the key areas addressed. The appearance of new species of hymenoptera that are potentially allergenic in Spain and the associated diagnostic and therapeutic problems are also described. Finally, we analyze the issue of mast cell activation syndrome closely related to hymenoptera allergy, which has become a new diagnostic challenge for allergists given its high prevalence in patients with venom anaphylaxis.

  9. Applicability of geomechanical classifications for estimation of strength properties in Brazilian rock masses.

    PubMed

    Santos, Tatiana B; Lana, Milene S; Santos, Allan E M; Silveira, Larissa R C

    2017-01-01

    Many authors have been proposed several correlation equations between geomechanical classifications and strength parameters. However, these correlation equations have been based in rock masses with different characteristics when compared to Brazilian rock masses. This paper aims to study the applicability of the geomechanical classifications to obtain strength parameters of three Brazilian rock masses. Four classification systems have been used; the Rock Mass Rating (RMR), the Rock Mass Quality (Q), the Geological Strength Index (GSI) and the Rock Mass Index (RMi). A strong rock mass and two soft rock masses with different degrees of weathering located in the cities of Ouro Preto and Mariana, Brazil; were selected for the study. Correlation equations were used to estimate the strength properties of these rock masses. However, such correlations do not always provide compatible results with the rock mass behavior. For the calibration of the strength values obtained through the use of classification systems, ​​stability analyses of failures in these rock masses have been done. After calibration of these parameters, the applicability of the various correlation equations found in the literature have been discussed. According to the results presented in this paper, some of these equations are not suitable for the studied rock masses.

  10. Geomechanical Response of Jointed Caprock During CO2 Geological Sequestration

    NASA Astrophysics Data System (ADS)

    Newell, P.; Martinez, M. J.; Bishop, J. E.

    2014-12-01

    Geological sequestration of CO2 refers to the injection of supercritical CO2 into deep reservoirs trapped beneath a low-permeability caprock formation. Maintaining caprock integrity during the injection process is the most important factor for a successful injection. In this work we evaluate the potential for jointed caprock during injection scenarios using coupled three-dimensional multiphase flow and geomechanics modeling. Evaluation of jointed/fractured caprock systems is of particular concern to CO2 sequestration because creation or reactivation of joints (mechanical damage) can lead to enhanced pathways for leakage. In this work, we use an equivalent continuum approach to account for the joints within the caprock. Joint's aperture and non-linear stiffness of the caprock will be updated dynamically based on the effective normal stress. Effective permeability field will be updated based on the joints' aperture creating an anisotropic permeability field throughout the caprock. This feature would add another coupling between the solid and fluid in addition to basic Terzaghi's effective stress concept. In this study, we evaluate the impact of the joint's orientation and geometry of caprock and reservoir layers on geomechanical response of the CO2 geological systems. This work is supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  11. Issues in Moderation of National Curriculum Assessment at Key Stage 3.

    ERIC Educational Resources Information Center

    Cowling, Les

    1994-01-01

    Highlights the issues of moderation of teacher judgments for accountability and moderation for achieving consistent assessments. Discusses the meaning of moderation, the need for moderating teacher judgments, approaches to moderation, methods of moderation, and most appropriate methods of moderation at Key Stage 3. Presents an approach to…

  12. Final Scientific/Technical Report for project “Geomechanical Monitoring for CO 2 Hub Storage: Production and Injection at Kevin Dome

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

    Daley, Thomas M.; Vasco, Don; Ajo-Franklin, Jonathan

    After learning that the TDS value in the target injection formation at the Kevin Dome site is too low to qualify for an EPA Class VI CO2 injection permit, the BSCSP project was re-scoped such that injection of CO2 is no longer planned. With no injection planned, the Geomechanics project was closed. In this final report, we describe the objective and approach of the project as proposed, and the limited results obtained before stopping work. The objective of the proposed research was the development & validation of an integrated monitoring approach for quantifying the interactions between large-scale geological carbon storagemore » (GCS) and subsurface geomechanical state, particularly perturbations relevant to reservoir integrity such as fault reactivation and induced fracturing. In the short period of work before knowing the fate of the Kevin Dome project, we (1) researched designs for both the proposed InSAR corner reflectors as well as the near-surface 3C seismic stations; (2) developed preliminary elastic geomechanical models; (3) developed a second generation deformation prediction for the BSCSP Kevin Dome injection site; and (4) completed a preliminary map of InSAR monuments and shallow MEQ wells in the vicinity of the BSCSP injection pad.« less

  13. User's guide of TOUGH2-EGS-MP: A Massively Parallel Simulator with Coupled Geomechanics for Fluid and Heat Flow in Enhanced Geothermal Systems VERSION 1.0

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

    Xiong, Yi; Fakcharoenphol, Perapon; Wang, Shihao

    2013-12-01

    TOUGH2-EGS-MP is a parallel numerical simulation program coupling geomechanics with fluid and heat flow in fractured and porous media, and is applicable for simulation of enhanced geothermal systems (EGS). TOUGH2-EGS-MP is based on the TOUGH2-MP code, the massively parallel version of TOUGH2. In TOUGH2-EGS-MP, the fully-coupled flow-geomechanics model is developed from linear elastic theory for thermo-poro-elastic systems and is formulated in terms of mean normal stress as well as pore pressure and temperature. Reservoir rock properties such as porosity and permeability depend on rock deformation, and the relationships between these two, obtained from poro-elasticity theories and empirical correlations, are incorporatedmore » into the simulation. This report provides the user with detailed information on the TOUGH2-EGS-MP mathematical model and instructions for using it for Thermal-Hydrological-Mechanical (THM) simulations. The mathematical model includes the fluid and heat flow equations, geomechanical equation, and discretization of those equations. In addition, the parallel aspects of the code, such as domain partitioning and communication between processors, are also included. Although TOUGH2-EGS-MP has the capability for simulating fluid and heat flows coupled with geomechanical effects, it is up to the user to select the specific coupling process, such as THM or only TH, in a simulation. There are several example problems illustrating applications of this program. These example problems are described in detail and their input data are presented. Their results demonstrate that this program can be used for field-scale geothermal reservoir simulation in porous and fractured media with fluid and heat flow coupled with geomechanical effects.« less

  14. Data Assimilation of InSAR Surface Deformation Measurements for the Estimation of Reservoir Geomechanical Parameters in the Upper Adriatic Sedimentary Basin, Italy

    NASA Astrophysics Data System (ADS)

    Bau, D. A.; Alzraiee, A.; Ferronato, M.; Gambolati, G.; Teatini, P.

    2012-12-01

    pathways towards the improvement of current land subsidence modeling efforts. The DA framework presented here allows for merging, within an automated process, InSAR data into coupled reservoir-geomechanical model results. The framework relies upon Bayesian-based ensemble smoothing algorithms and has the potential to significantly reduce the uncertainty associated with compressibility vs. effective stress constitutive laws, as well as key geomechanical parameters characterizing the orthotropic behavior of the reservoir porous media and their spatial distribution. The DA framework is here applied using InSAR data collected over the "Lombardia" reservoir. The flexibility of smoothing algorithms is such that spatially distributed and possibly correlated measurement errors are accounted for in a relatively straightforward fashion, so that surface deformation data that are considered more reliable can be assigned a larger weight within the model calibration. A series of numerical simulation results are presented in order to assess the capabilities of the DA framework, its effectiveness, advantages and limitations.

  15. On the importance of the heterogeneity assumption in the characterization of reservoir geomechanical properties

    NASA Astrophysics Data System (ADS)

    Zoccarato, C.; Baù, D.; Bottazzi, F.; Ferronato, M.; Gambolati, G.; Mantica, S.; Teatini, P.

    2016-10-01

    The geomechanical analysis of a highly compartmentalized reservoir is performed to simulate the seafloor subsidence due to gas production. The available observations over the hydrocarbon reservoir consist of bathymetric surveys carried out before and at the end of a 10-yr production life. The main goal is the calibration of the reservoir compressibility cM, that is, the main geomechanical parameter controlling the surface response. Two conceptual models are considered: in one (i) cM varies only with the depth and the vertical effective stress (heterogeneity due to lithostratigraphic variability); in another (ii) cM varies also in the horizontal plane, that is, it is spatially distributed within the reservoir stratigraphic units. The latter hypothesis accounts for a possible partitioning of the reservoir due to the presence of sealing faults and thrusts that suggests the idea of a block heterogeneous system with the number of reservoir blocks equal to the number of uncertain parameters. The method applied here relies on an ensemble-based data assimilation (DA) algorithm (i.e. the ensemble smoother, ES), which incorporates the information from the bathymetric measurements into the geomechanical model response to infer and reduce the uncertainty of the parameter cM. The outcome from conceptual model (i) indicates that DA is effective in reducing the cM uncertainty. However, the maximum settlement still remains underestimated, while the areal extent of the subsidence bowl is overestimated. We demonstrate that the selection of the heterogeneous conceptual model (ii) allows to reproduce much better the observations thus removing a clear bias of the model structure. DA allows significantly reducing the cM uncertainty in the five blocks (out of the seven) characterized by large volume and large pressure decline. Conversely, the assimilation of land displacements only partially constrains the prior cM uncertainty in the reservoir blocks marginally contributing to the

  16. Key issues and technical route of cyber physical distribution system

    NASA Astrophysics Data System (ADS)

    Zheng, P. X.; Chen, B.; Zheng, L. J.; Zhang, G. L.; Fan, Y. L.; Pei, T.

    2017-01-01

    Relying on the National High Technology Research and Development Program, this paper introduced the key issues in Cyber Physical Distribution System (CPDS), mainly includes: composite modelling method and interaction mechanism, system planning method, security defence technology, distributed control theory. Then on this basis, the corresponding technical route is proposed, and a more detailed research framework along with main schemes to be adopted is also presented.

  17. Key Issues in Sex Education: Reflecting on Teaching, Learning and Assessment

    ERIC Educational Resources Information Center

    Oerton, Sarah; Bowen, Helen

    2014-01-01

    Drawing upon critical reflections of staff and student experiences of teaching, learning and assessment on an undergraduate module entitled Key Issues in Sex Education, we discuss the strategies used to engage students in debates around sex and relationships education (SRE). To date, there is little research which evaluates how formal assessments…

  18. Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals

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

    Nguyen, Ba Nghiep; Hou, Zhangshuan; Bacon, Diana H.

    This article develops a novel multiscale modeling approach to analyze CO2 reservoirs using Pacific Northwest National Laboratory’s STOMP-CO2-R code that is interfaced with the ABAQUS® finite element package. The STOMP-CO2-R/ABAQUS® sequentially coupled simulator accounts for the reactive transport of CO2 causing mineral composition changes that modify the geomechanical properties of reservoir rocks and seals. Formation rocks’ elastic properties that vary during CO2 injection and govern the poroelastic behavior of rocks are modeled by an Eshelby-Mori-Tanka approach (EMTA) implemented in ABAQUS® via user-subroutines. The computational tool incorporates the change in rock permeability due to both geochemistry and geomechanics. A three-dimensional (3D)more » STOMP-CO2-R model for a model CO2 reservoir containing a vertical fault is built to analyze a formation containing a realistic geochemical reaction network with 5 minerals: albite, anorthite, calcite, kaolinite and quartz. A 3D ABAQUS® model that maps the above STOMP-CO2-R model is built for the analysis using STOMP-CO2-R/ABAQUS®. The results show that the changes in volume fraction of minerals include dissolution of anorthite, precipitation of calcite and kaolinite, with little change in the albite volume fraction. After a long period of CO2 injection the mineralogical and geomechanical changes significantly reduced the permeability and elastic modulus of the reservoir (between the base and caprock) in front of the fault leading to a reduction of the pressure margin to fracture at and beyond the injection location. The impact of reactive transport of CO2 on the geomechanical properties of reservoir rocks and seals are studied in terms of mineral composition changes that directly affect the rock stiffness, stress and strain distributions as well as the pressure margin to fracture.« less

  19. Human Health Effects of Trichloroethylene: Key Findings and Scientific Issues

    PubMed Central

    Jinot, Jennifer; Scott, Cheryl Siegel; Makris, Susan L.; Cooper, Glinda S.; Dzubow, Rebecca C.; Bale, Ambuja S.; Evans, Marina V.; Guyton, Kathryn Z.; Keshava, Nagalakshmi; Lipscomb, John C.; Barone, Stanley; Fox, John F.; Gwinn, Maureen R.; Schaum, John; Caldwell, Jane C.

    2012-01-01

    Background: In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) completed a toxicological review of trichloroethylene (TCE) in September 2011, which was the result of an effort spanning > 20 years. Objectives: We summarized the key findings and scientific issues regarding the human health effects of TCE in the U.S. EPA’s toxicological review. Methods: In this assessment we synthesized and characterized thousands of epidemiologic, experimental animal, and mechanistic studies, and addressed several key scientific issues through modeling of TCE toxicokinetics, meta-analyses of epidemiologic studies, and analyses of mechanistic data. Discussion: Toxicokinetic modeling aided in characterizing the toxicological role of the complex metabolism and multiple metabolites of TCE. Meta-analyses of the epidemiologic data strongly supported the conclusions that TCE causes kidney cancer in humans and that TCE may also cause liver cancer and non-Hodgkin lymphoma. Mechanistic analyses support a key role for mutagenicity in TCE-induced kidney carcinogenicity. Recent evidence from studies in both humans and experimental animals point to the involvement of TCE exposure in autoimmune disease and hypersensitivity. Recent avian and in vitro mechanistic studies provided biological plausibility that TCE plays a role in developmental cardiac toxicity, the subject of substantial debate due to mixed results from epidemiologic and rodent studies. Conclusions: TCE is carcinogenic to humans by all routes of exposure and poses a potential human health hazard for noncancer toxicity to the central nervous system, kidney, liver, immune system, male reproductive system, and the developing embryo/fetus. PMID:23249866

  20. Training: Who Needs It? Research Report 1995. Key Issues for Providers.

    ERIC Educational Resources Information Center

    Hotel and Catering Training Co., London (England).

    Aimed at all those involved in the supply of training and vocational education for the hospitality industry, this report summarizes findings of the research report, "Training Who Needs It?" It draws out and explores in more detail key issues relating to the provision of training, support, and related initiatives for the industry. Section…

  1. Towards Providing Culturally Aware Nutritional Care for Transgender People: Key Issues and Considerations.

    PubMed

    Fergusson, Pamela; Greenspan, Nicole; Maitland, Lukas; Huberdeau, Rémy

    2018-06-01

    Transgender people are an important group for whom access to healthcare is often problematic. Dietitians need to be aware of key issues in transgender health to provide culturally competent clinical nutritional care. This article serves as a primer, clarifying key terms and concepts, exploring the impact of stigma and discrimination on health and nutrition for people from transgender communities, and offering practical advice for nutritional and other related issues. Education for dietitians both pre- and postqualification is an important part of improving care and building skills and awareness of cultural humility. Transgender people may be at increased nutritional risk due to increased risk of cardiovascular disease, HIV, body image issues, and food insecurity. This risk profile, along with the history of trauma both outside and related to the medical community means that there is an urgent need for dietitians to develop practice tools for assessment, care, and referral to improve the nutritional status and well-being of this client group.

  2. Key Health Information Technologies and Related Issues for Iran: A Qualitative Study.

    PubMed

    Hemmat, Morteza; Ayatollahi, Haleh; Maleki, Mohammadreza; Saghafi, Fatemeh

    2018-01-01

    Planning for the future of Health Information Technology (HIT) requires applying a systematic approach when conducting foresight studies. The aim of this study was to identify key health information technologies and related issues for Iran until 2025. This was a qualitative study and the participants included experts and policy makers in the field of health information technology. In-depth semi-structured interviews were conducted and data were analyzed by using framework analysis and MAXQDA software. The findings revealed that the development of national health information network, electronic health records, patient health records, a cloud-based service center, interoperability standards, patient monitoring technologies, telehealth, mhealth, clinical decision support systems, health information technology and mhealth infrastructure were found to be the key technologies for the future. These technologies could influence the economic, organizational and individual levels. To achieve them, the economic and organizational obstacles need to be overcome. In this study, a number of key technologies and related issues were identified. This approach can help to focus on the most important technologies in the future and to priorities these technologies for better resource allocation and policy making.

  3. Key Health Information Technologies and Related Issues for Iran: A Qualitative Study

    PubMed Central

    Hemmat, Morteza; Ayatollahi, Haleh; Maleki, Mohammadreza; Saghafi, Fatemeh

    2018-01-01

    Background and Objective: Planning for the future of Health Information Technology (HIT) requires applying a systematic approach when conducting foresight studies. The aim of this study was to identify key health information technologies and related issues for Iran until 2025. Methods: This was a qualitative study and the participants included experts and policy makers in the field of health information technology. In-depth semi-structured interviews were conducted and data were analyzed by using framework analysis and MAXQDA software. Results: The findings revealed that the development of national health information network, electronic health records, patient health records, a cloud-based service center, interoperability standards, patient monitoring technologies, telehealth, mhealth, clinical decision support systems, health information technology and mhealth infrastructure were found to be the key technologies for the future. These technologies could influence the economic, organizational and individual levels. To achieve them, the economic and organizational obstacles need to be overcome. Conclusion: In this study, a number of key technologies and related issues were identified. This approach can help to focus on the most important technologies in the future and to priorities these technologies for better resource allocation and policy making. PMID:29854016

  4. New Doctoral Graduates in the Knowledge Economy: Trends and Key Issues

    ERIC Educational Resources Information Center

    Pedersen, Heidi Skovgaard

    2014-01-01

    This paper examines the key issues at stake for national economies in increasing the number of PhDs to meet expected needs for human capital in science, technology and innovation using illustrations mainly from the European Commission's "Careers of Doctorate Holders" surveys on PhD labour market outcomes; it has been shown that PhD…

  5. Understanding Key Education Issues: How We Got Here and Where We Go from Here

    ERIC Educational Resources Information Center

    Lynch, Matthew

    2017-01-01

    In this age of education innovation and reform, schools must evolve and react to current policy trends. This accessible book offers research-based insights into six key educational trends and issues that are impacting K-12 learning today: year-round schooling, assessments, educating minorities, anti-intellectualism, issues of social promotion and…

  6. Numerical investigation and Uncertainty Quantification of the Impact of the geological and geomechanical properties on the seismo-acoustic responses of underground chemical explosions

    NASA Astrophysics Data System (ADS)

    Ezzedine, S. M.; Pitarka, A.; Vorobiev, O.; Glenn, L.; Antoun, T.

    2017-12-01

    We have performed three-dimensional high resolution simulations of underground chemical explosions conducted recently in jointed rock outcrop as part of the Source Physics Experiments (SPE) being conducted at the Nevada National Security Site (NNSS). The main goal of the current study is to investigate the effects of the structural and geomechanical properties on the spall phenomena due to underground chemical explosions and its subsequent effect on the seismo-acoustic signature at far distances. Two parametric studies have been undertaken to assess the impact of different 1) conceptual geological models including a single layer and two layers model, with and without joints and with and without varying geomechanical properties, and 2) depth of bursts of the chemical explosions and explosion yields. Through these investigations we have explored not only the near-field response of the chemical explosions but also the far-field responses of the seismic and the acoustic signatures. The near-field simulations were conducted using the Eulerian and Lagrangian codes, GEODYN and GEODYN -L, respectively, while the far-field seismic simulations were conducted using the elastic wave propagation code, WPP, and the acoustic response using the Kirchhoff-Helmholtz-Rayleigh time-dependent approximation code, KHR. Though a series of simulations we have recorded the velocity field histories a) at the ground surface on an acoustic-source-patch for the acoustic simulations, and 2) on a seismic-source-box for the seismic simulations. We first analyzed the SPE3 experimental data and simulated results, then simulated SPE4-prime, SPE5, and SPE6 to anticipate their seismo-acoustic responses given conditions of uncertainties. SPE experiments were conducted in a granitic formation; we have extended the parametric study to include other geological settings such dolomite and alluvial formations. These parametric studies enabled us 1) investigating the geotechnical and geophysical key parameters

  7. Hydro-geomechanical behaviour of gas-hydrate bearing soils during gas production through depressurization and CO2 injection

    NASA Astrophysics Data System (ADS)

    Deusner, C.; Gupta, S.; Kossel, E.; Bigalke, N.; Haeckel, M.

    2015-12-01

    Results from recent field trials suggest that natural gas could be produced from marine gas hydrate reservoirs at compatible yields and rates. It appears, from a current perspective, that gas production would essentially be based on depressurization and, when facing suitable conditions, be assisted by local thermal stimulation or gas hydrate conversion after injection of CO2-rich fluids. Both field trials, onshore in the Alaska permafrost and in the Nankai Trough offshore Japan, were accompanied by different technical issues, the most striking problems resulting from un-predicted geomechanical behaviour, sediment destabilization and catastrophic sand production. So far, there is a lack of experimental data which could help to understand relevant mechanisms and triggers for potential soil failure in gas hydrate production, to guide model development for simulation of soil behaviour in large-scale production, and to identify processes which drive or, further, mitigate sand production. We use high-pressure flow-through systems in combination with different online and in situ monitoring tools (e.g. Raman microscopy, MRI) to simulate relevant gas hydrate production scenarios. Key components for soil mechanical studies are triaxial systems with ERT (Electric resistivity tomography) and high-resolution local strain analysis. Sand production control and management is studied in a novel hollow-cylinder-type triaxial setup with a miniaturized borehole which allows fluid and particle transport at different fluid injection and flow conditions. Further, the development of a large-scale high-pressure flow-through triaxial test system equipped with μ-CT is ongoing. We will present results from high-pressure flow-through experiments on gas production through depressurization and injection of CO2-rich fluids. Experimental data are used to develop and parametrize numerical models which can simulate coupled process dynamics during gas-hydrate formation and gas production.

  8. Emergency management in health: key issues and challenges in the UK.

    PubMed

    Lee, Andrew C K; Phillips, Wendy; Challen, Kirsty; Goodacre, Steve

    2012-10-19

    Emergency planning in the UK has grown considerably in recent years, galvanised by the threat of terrorism. However, deficiencies in NHS emergency planning were identified and the evidence-base that underpins it is questionable. Inconsistencies in terminologies and concepts also exist. Different models of emergency management exist internationally but the optimal system is unknown. This study examines the evidence-base and evidence requirements for emergency planning in the UK health context. The study involved semi-structured interviews with key stakeholders and opinion leaders. Purposive sampling was used to obtain a breadth of views from various agencies involved in emergency planning and response. Interviews were then analysed using a grounded approach using standard framework analysis techniques. We conducted 17 key informant interviews. Interviewees identified greater gaps in operational than technical aspects of emergency planning. Social and behavioural knowledge gaps were highlighted with regards to how individuals and organisations deal with risk and behave in emergencies. Evidence-based approaches to public engagement and for developing community resilience to disasters are lacking. Other gaps included how knowledge was developed and used. Conflicting views with regards to the optimal configuration and operation of the emergency management system were voiced. Four thematic categories for future research emerged:(i) Knowledge-base for emergency management: Further exploration is needed of how knowledge is acquired, valued, disseminated, adopted and retained.(ii) Social and behavioural issues: Greater understanding of how individuals approach risk and behave in emergencies is required.(iii) Organisational issues in emergencies: Several conflicting organisational issues were identified; value of planning versus plans, flexible versus standardized procedures, top-down versus bottom-up engagement, generic versus specific planning, and reactive versus

  9. Fully coupled two-phase flow and poromechanics modeling of coalbed methane recovery: Impact of geomechanics on production rate

    DOE PAGES

    Ma, Tianran; Rutqvist, Jonny; Oldenburg, Curtis M.; ...

    2017-06-03

    This study presents the development and application of a fully coupled two-phase (methane and water) flow, transport, and poromechanics num erical model for the analysis of geomechanical impacts on coalbed methane (CBM) production. The model considers changes in two-phase fluid flow properties, i.e., coal porosity, permeability, water retention, and relative permeability curves through changes in cleat fractures induced by effective stress variations and desorption-induced shrinkage. The coupled simulator is first verified for poromechanics coupling, and simulation parameters of a CBM reservoir model are calibrated by history matching against one year of CBM production field data from Shanxi Province, China. Then,more » the verified simulator and the calibrated CBM reservoir model are used for predicting the impact of geomechanics on the production rate for twenty years of continuous CBM production. The simulation results show that desorption-induced shrinkage is the dominant process in increasing permeability in the near wellbore region. Away from the wellbore, desorption-induced shrinkage is weaker, and permeability is reduced by pressure depletion and increased effective stress. A sensitivity analysis shows that for coal with a higher sorption strain, a larger initial Young's modulus and a smaller Poisson's ratio promote the enhancement of permeability as well as an increased production rate. Moreover, the conceptual model of the cleat system, whether dominated by vertical cleats with permeability correlated to horizontal stress or with permeability correlated to mean stress, can have a significant impact on the predicted production rate. Overall, the study clearly demonstrates and confirms the critical importance of considering geomechanics for an accurate prediction of CBM production.« less

  10. Fully coupled two-phase flow and poromechanics modeling of coalbed methane recovery: Impact of geomechanics on production rate

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

    Ma, Tianran; Rutqvist, Jonny; Oldenburg, Curtis M.

    This study presents the development and application of a fully coupled two-phase (methane and water) flow, transport, and poromechanics num erical model for the analysis of geomechanical impacts on coalbed methane (CBM) production. The model considers changes in two-phase fluid flow properties, i.e., coal porosity, permeability, water retention, and relative permeability curves through changes in cleat fractures induced by effective stress variations and desorption-induced shrinkage. The coupled simulator is first verified for poromechanics coupling, and simulation parameters of a CBM reservoir model are calibrated by history matching against one year of CBM production field data from Shanxi Province, China. Then,more » the verified simulator and the calibrated CBM reservoir model are used for predicting the impact of geomechanics on the production rate for twenty years of continuous CBM production. The simulation results show that desorption-induced shrinkage is the dominant process in increasing permeability in the near wellbore region. Away from the wellbore, desorption-induced shrinkage is weaker, and permeability is reduced by pressure depletion and increased effective stress. A sensitivity analysis shows that for coal with a higher sorption strain, a larger initial Young's modulus and a smaller Poisson's ratio promote the enhancement of permeability as well as an increased production rate. Moreover, the conceptual model of the cleat system, whether dominated by vertical cleats with permeability correlated to horizontal stress or with permeability correlated to mean stress, can have a significant impact on the predicted production rate. Overall, the study clearly demonstrates and confirms the critical importance of considering geomechanics for an accurate prediction of CBM production.« less

  11. Key technology issues for space robotic systems

    NASA Technical Reports Server (NTRS)

    Schappell, Roger T.

    1987-01-01

    Robotics has become a key technology consideration for the Space Station project to enable enhanced crew productivity and to maximize safety. There are many robotic functions currently being studied, including Space Station assembly, repair, and maintenance as well as satellite refurbishment, repair, and retrieval. Another area of concern is that of providing ground based experimenters with a natural interface that they might directly interact with their hardware onboard the Space Station or ancillary spacecraft. The state of the technology is such that the above functions are feasible; however, considerable development work is required for operation in this gravity-free vacuum environment. Furthermore, a program plan is evolving within NASA that will capitalize on recent government, university, and industrial robotics research and development (R and D) accomplishments. A brief summary is presented of the primary technology issues and physical examples are provided of the state of the technology for the initial operational capability (IOC) system as well as for the eventual final operational capability (FOC) Space Station.

  12. Prediction of Reservoir Properties for Geomechanical Analysis Using 3-D Seismic Data and Rock Physics Modeling in the Vaca Muerta Formation, Neuquen Basin, Argentina

    NASA Astrophysics Data System (ADS)

    Convers-Gomez, Carlos E.

    The Vaca Muerta Formation in the Neuquen Basin has recently received a lot of attention from oil companies interested in developing its shale resources. Early identification of potential zones with possible good production is extremely important to optimize the return on capital investment. Developing a work flow in shale plays that associates an effective hydraulic fracture response with the presence of hydrocarbons is crucial for economic success. The vertical and lateral heterogeneity of rock properties are critical factors that impact production. The integration of 3D seismic and well data is necessary for prediction of rock properties and identifies their distribution in the rock, which can also be integrated with geomechanical properties to model the rock response favorable to hydraulic stimulation. This study includes a 3D seismic survey and six vertical wells with full log suites in each well. The well logs allowed for the computation of a pre-stack model-based inversion which uses seismic data to estimate rock property volumes. An inverse relationship between P-impedance and Total Organic Content (TOC) was observed and quantified. Likewise, a direct relationship between P-impedance and volume of carbonate was observed. The volume of kerogen, type of clay, type of carbonate and fluid pressure all control the geomechanical properties of the formation when subject to hydraulic fracturing. Probabilistic Neural Networks were then used to predict the lateral and vertical heterogeneity of rock properties. TOC and volume of kerogen behaved as adequate indicators of possible zones with high presence of hydrocarbons. Meanwhile, the volume of carbonate was a valid indicator of brittle-ductile rock. The predicted density volume was used to estimate geomechanical properties (Young's Modulus and Poisson's Ratio) and to identify the zones that have a better response to hydraulic stimulation. During the analysis of geomechanical properties, Young's Modulus was observed to

  13. Several key issues on using 137Cs method for soil erosion estimation

    USDA-ARS?s Scientific Manuscript database

    This work was to examine several key issues of using the cesium-137 method to estimate soil erosion rates in order to improve and standardize the method. Based on the comprehensive review and synthesis of a large body of published literature and the author’s extensive research experience, several k...

  14. Key Questions on the Obama Administration's 2014 Education Budget Request. Issue Brief

    ERIC Educational Resources Information Center

    New America Foundation, 2013

    2013-01-01

    President Obama sent his fiscal year 2014 budget request to Congress on April 10, 2013. The New America Foundation's Education Policy Program released this subsequent issue brief, "Key Questions on the Obama Administration's 2014 Budget Request." Obama's budget request totals $71.2 billion in appropriations funding for the U.S.…

  15. Building and Strengthening Policy Research Capacity: Key Issues in Canadian Higher Education

    ERIC Educational Resources Information Center

    Jones, Glen A.

    2014-01-01

    Given the importance of higher education in social and economic development, governments need to build a strong higher education data and policy research infrastructure to support informed decision-making, provide policy advice, and offer a critical assessment of key trends and issues. The author discusses the decline of higher education policy…

  16. Maori responsiveness in health and medical research: key issues for researchers (part 1).

    PubMed

    Sporle, Andrew; Koea, Jonathan

    2004-08-06

    Application for contestable government-research funding and ethical approval requires researchers to outline how their intended research project contributes to Maori development or advancement. When formulating their research proposals, the key issues for researchers are research utility, defining Maori, informed consent, confidentiality, issues with human tissues and genetic material, participant remuneration and recognition (koha), intellectual property, and involvement of local Maori health or social services. The most common Maori responsiveness issues in research applications can be readily approached by researchers who address straightforward methodological concerns, by working through precedents established by peers and colleagues, as well as by working with end-users of their research.

  17. Geomechanical analysis applied to geological carbon dioxide sequestration, induced seismicity in deep mines, and detection of stress-induced velocity anisotropy in sub-salt environments

    NASA Astrophysics Data System (ADS)

    Lucier, Amie Marie

    and injection induced micro-seismicity are implemented. The second issue to which we apply geomechanical analysis in this thesis is mining-induced stress perturbations and induced seismicity in the TauTona gold mine, which is located in the Witwatersrand Basin of South Africa and is one of the deepest underground mines in the world. In the first investigation, we developed and tested a new technique for determining the virgin stress state near the TauTona gold mine. This technique follows an iterative forward modeling approach that combines observations of drilling induced borehole failures in borehole images, boundary element modeling of the mining-induced stress perturbations, and forward modeling of borehole failures based on the results of the boundary element modeling. The final result was a well constrained range of principal stress orientations and magnitudes that are consistent with all the observed failures and other stress indicators. In the second investigation, we used this constrained stress state to examine the likelihood of faulting to occur both on pre-existing fault planes that are optimally oriented to the virgin stress state and on faults affected by the mining-perturbed stress field, the latter of which is calculated with boundary element modeling. We made several recommendations that could potentially increase safety in deep South African mines as development continues. Finally, the third issue addressed in this thesis is the detection of stress-induced shear wave velocity anisotropy in a sub-salt environment. In this study, we tested a technique proposed by Boness and Zoback (2006) to identify structure-induced velocity anisotropy and isolate possible stress-induced velocity anisotropy. The investigation used cross-dipole sonic data from three deep water sub-salt wells in the Gulf of Mexico. First, we determined the parameters necessary to ensure the quality of the fast azimuth data used in our analysis. We then characterized the quality

  18. Geomechanical modelling of induced seismicity using Coulomb stress and pore pressure changes

    NASA Astrophysics Data System (ADS)

    Zhao, B.; Shcherbakov, R.

    2016-12-01

    In recent years, there has been a dramatic increase in seismicity (earthquakes) due to anthropogenic activities related to the unconventional oil and gas exploration in the Western Canada Sedimentary Basin (WCSB). There are compelling evidences that hydraulic fracturing and wastewater injection operations play a key role in induced seismicity in the WCSB; however, their physical mechanisms are still not fully understood. Therefore, this study focuses on exploring the physical mechanisms of induced seismicity and developing a realistic geomechanical model by incorporating the past seismicity and well production data. In this work, we model the Coulomb stress changes due to past moderate (magnitude greater than 3 with known fault plane solutions) induced earthquakes and pore pressure changes due to wastewater injection in Alberta, specifically in Fox Creek and Fort St. John areas. Relationships between Coulombs stress changes, fault geometry and orientation and subsequent earthquake locations are tested. Subsurface flow due to injection well operations is studied to model the pore pressure changes in time and space, using known well production data, which include well types, well locations and water extraction and injection rates. By modelling the changes in pore pressure and Coulomb stress, we aim at constraining the time scale of occurrence of possible future earthquakes. The anticipating results can help to control the parameters of anthropogenic energy related operations such as hydraulic fracturing and wastewater injection in mitigating the risk due to induced seismicity.

  19. Pretest reference calculation for the 6. 1 meter (20 ft) wide drifts of the Geomechanical Evaluation (WIPP Room G in situ experiment)

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

    Morgan, H.S.; Stone, C.M.

    A pretest reference calculation for the Geomechanical Evaluation or Room G experiment is presented. The Geomechanical Evaluation is one of several large-scale in situ tests currently under construction near Carlsbad, New Mexico, at the site of the Waste Isolation Pilot Plant (WIPP). The Room G experiment consists of isolated, two-dimensional drifts with different room spans, an isolated drift intersection, and a wedge pillar. The primary purpose of the experiment is to provide data for validating computational modeling capabilities used in analyzing nuclear waste repositories in salt. The calculation presented here addresses only one portion of the test, namely isolated driftmore » configurations which are initially 6.1 m (20 ft) wide by 3.05 m (10 ft) high. The Geomechanical Evaluation is heavily instrumented for monitoring deformations due to creep of the salt. Data from the experiment are not available at the present time, but the measurements for Room G will eventually be compared to the results presented in this report to assess and improve structural modeling capabilities for the WIPP. The model used for this calculation represents the state of the art at the present time. A large number of plots are included since an appropriate result is presented for every gage location associated with the 6.1 m wide drifts. 53 refs., 53 figs., 3 tabs.« less

  20. Key issues concerning environmental enrichment for laboratory-held fish species.

    PubMed

    Williams, T D; Readman, G D; Owen, S F

    2009-04-01

    An improved knowledge and understanding of the fundamental biological requirements is needed for many of the species of fish held in captivity and, without this knowledge it is difficult to determine the optimal conditions for laboratory culture. The aim of this paper is to review the key issues concerning environmental enrichment for laboratory-held fish species and identify where improvements are required. It provides background information on environmental enrichment, describes enrichment techniques currently used in aquatic ecotoxicology studies, identifies potential restrictions in their use and discusses why more detailed and species-specific guidance is needed.

  1. EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and ...

    EPA Pesticide Factsheets

    EPA is releasing the draft report, EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (Volume 1), that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from other Federal agencies and White House Offices are provided below with external peer review panel comments. The objective of this report is to respond to the NAS coments on dose-response modeling conducted in the EPA Reassessment of the health effects associated with dioxin exposure.

  2. Geo-Mechanical Characterization of Carbonate Rock Masses by Means of Laser Scanner Technique

    NASA Astrophysics Data System (ADS)

    Palma, Biagio; Parise, Mario; Ruocco, Anna

    2017-12-01

    Knowledge of the geometrical and structural setting of rock masses is crucial to evaluate the stability and to design the most suitable stabilization works. In this work we use the Terrestrial Laser Scanning (TLS) at the site of the Grave of the Castellana Caves, a famous show cave in southern Italy. The Grave is the natural access to the cave system, produced by collapse of the vault, due to upward progression of instabilities in the carbonate rock masses. It is about 55-m high, bell-shaped, with maximum width of 120 m. Aim of the work is the characterization of carbonate rock masses from the structural and geo-mechanical standpoints through the use of innovative survey techniques. TLS survey provides a product consisting of millions of geo-referenced points, to be managed in space, to become a suitable database for the morphological and geological-structural analysis. Studying by means of TLS a rock face, partly inaccessible or located in very complex environments, allows to investigate slopes in their overall areal extent, thus offering advantages both as regards safety of the workers and time needed for the survey. In addition to TLS, the traditional approach was also followed by performing scanlines surveys along the rims of the Grave, following the ISRM recommendations for characterization of discontinuity in rock masses. A quantitative comparison among the data obtained by TLS technique and those deriving from the classical geo-mechanical survey is eventually presented, to discuss potentiality of drawbacks of the different techniques used for surveying the rock masses.

  3. A Model to Couple Flow, Thermal and Reactive Chemical Transport, and Geo-mechanics in Variably Saturated Media

    NASA Astrophysics Data System (ADS)

    Yeh, G. T.; Tsai, C. H.

    2015-12-01

    This paper presents the development of a THMC (thermal-hydrology-mechanics-chemistry) process model in variably saturated media. The governing equations for variably saturated flow and reactive chemical transport are obtained based on the mass conservation principle of species transport supplemented with Darcy's law, constraint of species concentration, equation of states, and constitutive law of K-S-P (Conductivity-Degree of Saturation-Capillary Pressure). The thermal transport equation is obtained based on the conservation of energy. The geo-mechanic displacement is obtained based on the assumption of equilibrium. Conventionally, these equations have been implicitly coupled via the calculations of secondary variables based on primary variables. The mechanisms of coupling have not been obvious. In this paper, governing equations are explicitly coupled for all primary variables. The coupling is accomplished via the storage coefficients, transporting velocities, and conduction-dispersion-diffusion coefficient tensor; one set each for every primary variable. With this new system of equations, the coupling mechanisms become clear. Physical interpretations of every term in the coupled equations will be discussed. Examples will be employed to demonstrate the intuition and superiority of these explicit coupling approaches. Keywords: Variably Saturated Flow, Thermal Transport, Geo-mechanics, Reactive Transport.

  4. Human Health Effects of Dichloromethane: Key Findings and Scientific Issues

    PubMed Central

    Schlosser, Paul M.; Bale, Ambuja S.; Gibbons, Catherine F.; Wilkins, Amina

    2014-01-01

    Background: The U.S. EPA’s Integrated Risk Information System (IRIS) completed an updated toxicological review of dichloromethane in November 2011. Objectives: In this commentary we summarize key results and issues of this review, including exposure sources, identification of potential health effects, and updated physiologically based pharmacokinetic (PBPK) modeling. Methods: We performed a comprehensive review of primary research studies and evaluation of PBPK models. Discussion: Hepatotoxicity was observed in oral and inhalation exposure studies in several studies in animals; neurological effects were also identified as a potential area of concern. Dichloromethane was classified as likely to be carcinogenic in humans based primarily on evidence of carcinogenicity at two sites (liver and lung) in male and female B6C3F1 mice (inhalation exposure) and at one site (liver) in male B6C3F1 mice (drinking-water exposure). Recent epidemiologic studies of dichloromethane (seven studies of hematopoietic cancers published since 2000) provide additional data raising concerns about associations with non-Hodgkin lymphoma and multiple myeloma. Although there are gaps in the database for dichloromethane genotoxicity (i.e., DNA adduct formation and gene mutations in target tissues in vivo), the positive DNA damage assays correlated with tissue and/or species availability of functional glutathione S-transferase (GST) metabolic activity, the key activation pathway for dichloromethane-induced cancer. Innovations in the IRIS assessment include estimation of cancer risk specifically for a presumed sensitive genotype (GST-theta-1+/+), and PBPK modeling accounting for human physiological distributions based on the expected distribution for all individuals 6 months to 80 years of age. Conclusion: The 2011 IRIS assessment of dichloromethane provides insights into the toxicity of a commonly used solvent. Citation: Schlosser PM, Bale AS, Gibbons CF, Wilkins A, Cooper GS. 2015. Human health

  5. Geomechanical Considerations for the Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Park, B. Y.

    2015-12-01

    Deep borehole disposal of high-level radioactive waste is under consideration as a potential alternative to shallower mined repositories. The disposal concept consists of drilling a borehole into crystalline basement rocks to a depth of 5 km, emplacement of canisters containing solid waste in the lower 2 km, and plugging and sealing the upper 3 km of the borehole. Crystalline rocks such as granites are particularly attractive for borehole emplacement because of their low permeability and porosity at depth, and high mechanical strength to resist borehole deformation. In addition, high overburden pressures contribute to sealing of some of the fractures that provide transport pathways. We present geomechanical considerations during construction (e.g., borehole breakouts, disturbed rock zone development, and creep closure), relevant to both the smaller-diameter characterization borehole (8.5") and the larger-diameter field test borehole (17"). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  6. Textual analysis of tobacco editorials: how are Key media gatekeepers framing the issues?

    PubMed

    Smith, Katherine Clegg; Wakefield, Melanie

    2005-01-01

    The news media's potential to promote awareness of health issues is established, and media advocacy is now an important tool in combating tobacco use. This study examines newspaper editors' perspectives of tobacco-related issues. This study presents a textual analysis of tobacco-related editorials. The data consist of editorials on tobacco from a sample of 310 U.S. daily newspapers over the course of 1 year (2001). Data were sampled from a random one-third of the days per month, yielding 162 editorials for analysis. A qualitative textual analysis was conducted. Each editorial was coded for theme, position, and frame. We analyzed the topics gaining editorial attention and the arguments made to support various perspectives. Editorials discussed a variety of both positive and negative news events, largely conveying support for tobacco-control objectives. Various organizing frames were used-supporting policy interventions, condemning the industry, highlighting individual rights, and expressing general cynicism were most prevalent. Editors largely promoted tobacco-control efforts, particularly policy advances. There was, however, little coverage of key issues such as health effects and addiction-perhaps because they are no longer perceived to be contentious. Advocates should seek to address this area and minimize the cynicism of key media gatekeepers to avoid undermining policy and individual change efforts.

  7. Identification and Characterization of Key Human Performance Issues and Research in the Next Generation Air Transportation System (NextGen)

    NASA Technical Reports Server (NTRS)

    Lee, Paul U.; Sheridan, Tom; Poage, james L.; Martin, Lynne Hazel; Jobe, Kimberly K.

    2010-01-01

    This report identifies key human-performance-related issues associated with Next Generation Air Transportation System (NextGen) research in the NASA NextGen-Airspace Project. Four Research Focus Areas (RFAs) in the NextGen-Airspace Project - namely Separation Assurance (SA), Airspace Super Density Operations (ASDO), Traffic Flow Management (TFM), and Dynamic Airspace Configuration (DAC) - were examined closely. In the course of the research, it was determined that the identified human performance issues needed to be analyzed in the context of NextGen operations rather than through basic human factors research. The main gaps in human factors research in NextGen were found in the need for accurate identification of key human-systems related issues within the context of specific NextGen concepts and better design of the operational requirements for those concepts. By focusing on human-system related issues for individual concepts, key human performance issues for the four RFAs were identified and described in this report. In addition, mixed equipage airspace with components of two RFAs were characterized to illustrate potential human performance issues that arise from the integration of multiple concepts.

  8. Preliminary assessment of in-situ geomechanical characteristics in drill hole USW G-1, Yucca Mountain, Nevada

    USGS Publications Warehouse

    Ellis, William L.; Swolfs, Henri S.

    1983-01-01

    Observations made during drilling and subsequent testing of the USW G-1 drill hole, Yucca Mountain, Nevada, provide qualitative insights into the in- situ geomechanical characteristics of the layered tuff units penetrated by the hole. Substantial drilling-fluid losses, and the occurrence of drilling-induced fracturing, are understandable in terms of the low, minimum horizontal stress magnitudes interpreted from six hydraulic-fracturing stress measurements conducted between hole depths of 640 and 1,300 meters. Although not confirmed directly by the hydraulic-fracturing data, other observations suggest that the minimum stress magnitudes in the more densely welded and brittle tuff layers may be even smaller than in the less welded and more ductile rocks. Stress-induced borehole ellipticity observed along most of the length of USW G-1 indicates that the horizontal stress components are not equal, and that the concentration of these stresses around the hole is sufficient to locally exceed the yield strength of the rock. The low, minimum horizontal stress magnitudes, perhaps variable with lithology, and the indications from borehole ellipticity of a high in-situ stress/strength ratio, indicate the need for further studies to characterize the structural and geomechanical properties of the rocks at depth in Yucca Mountain.

  9. A multimethod Global Sensitivity Analysis to aid the calibration of geomechanical models via time-lapse seismic data

    NASA Astrophysics Data System (ADS)

    Price, D. C.; Angus, D. A.; Garcia, A.; Fisher, Q. J.; Parsons, S.; Kato, J.

    2018-03-01

    Time-lapse seismic attributes are used extensively in the history matching of production simulator models. However, although proven to contain information regarding production induced stress change, it is typically only loosely (i.e. qualitatively) used to calibrate geomechanical models. In this study we conduct a multimethod Global Sensitivity Analysis (GSA) to assess the feasibility and aid the quantitative calibration of geomechanical models via near-offset time-lapse seismic data. Specifically, the calibration of mechanical properties of the overburden. Via the GSA, we analyse the near-offset overburden seismic traveltimes from over 4000 perturbations of a Finite Element (FE) geomechanical model of a typical High Pressure High Temperature (HPHT) reservoir in the North Sea. We find that, out of an initially large set of material properties, the near-offset overburden traveltimes are primarily affected by Young's modulus and the effective stress (i.e. Biot) coefficient. The unexpected significance of the Biot coefficient highlights the importance of modelling fluid flow and pore pressure outside of the reservoir. The FE model is complex and highly nonlinear. Multiple combinations of model parameters can yield equally possible model realizations. Consequently, numerical calibration via a large number of random model perturbations is unfeasible. However, the significant differences in traveltime results suggest that more sophisticated calibration methods could potentially be feasible for finding numerous suitable solutions. The results of the time-varying GSA demonstrate how acquiring multiple vintages of time-lapse seismic data can be advantageous. However, they also suggest that significant overburden near-offset seismic time-shifts, useful for model calibration, may take up to 3 yrs after the start of production to manifest. Due to the nonlinearity of the model behaviour, similar uncertainty in the reservoir mechanical properties appears to influence overburden

  10. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage in lined rock caverns

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

    Rutqvist, Jonny; Kim, Hyung-Mok; Ryu, Dong-Woo

    We applied coupled nonisothermal, multiphase fluid flow and geomechanical numerical modeling to study the coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in concrete-lined rock caverns. The paper focuses on CAES in lined caverns at relatively shallow depth (e.g., 100 m depth) in which a typical CAES operational pressure of 5 to 8 MPa is significantly higher than both ambient fluid pressure and in situ stress. We simulated a storage operation that included cyclic compression and decompression of air in the cavern, and investigated how pressure, temperature and stress evolve over several months of operation. Wemore » analyzed two different lining options, both with a 50 cm thick low permeability concrete lining, but in one case with an internal synthetic seal such as steel or rubber. For our simulated CAES system, the thermodynamic analysis showed that 96.7% of the energy injected during compression could be recovered during subsequent decompression, while 3.3% of the energy was lost by heat conduction to the surrounding media. Our geomechanical analysis showed that tensile effective stresses as high as 8 MPa could develop in the lining as a result of the air pressure exerted on the inner surface of the lining, whereas thermal stresses were relatively smaller and compressive. With the option of an internal synthetic seal, the maximum effective tensile stress was reduced from 8 to 5 MPa, but was still in substantial tension. We performed one simulation in which the tensile tangential stresses resulted in radial cracks and air leakage though the lining. This air leakage, however, was minor (about 0.16% of the air mass loss from one daily compression) in terms of CAES operational efficiency, and did not significantly impact the overall energy balance of the system. However, despite being minor in terms of energy balance, the air leakage resulted in a distinct pressure increase in the surrounding rock that could

  11. Geomechanical/Geochemical Modeling Studies Conducted within theInternational DECOVALEX Project

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

    Birkholzer, J.T.; Rutqvist, J.; Sonnenthal, E.L.

    2005-10-19

    The DECOVALEX project is an international cooperative project initiated by SKI, the Swedish Nuclear Power Inspectorate, with participation of about 10 international organizations. The general goal of this project is to encourage multidisciplinary interactive and cooperative research on modeling coupled thermo-hydro-mechanical-chemical (THMC) processes in geologic formations in support of the performance assessment for underground storage of radioactive waste. One of the research tasks, initiated in 2004 by the U.S. Department of Energy (DOE), addresses the long-term impact of geomechanical and geochemical processes on the flow conditions near waste emplacement tunnels. Within this task, four international research teams conduct predictive analysismore » of the coupled processes in two generic repositories, using multiple approaches and different computer codes. Below, we give an overview of the research task and report its current status.« less

  12. Geomechanical/ Geochemical Modeling Studies onducted Within the International DECOVALEX Project

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

    J.T. Birkholzer; J. Rutqvist; E.L. Sonnenthal

    2006-02-01

    The DECOVALEX project is an international cooperative project initiated by SKI, the Swedish Nuclear Power Inspectorate, with participation of about 10 international organizations. The general goal of this project is to encourage multidisciplinary interactive and cooperative research on modeling coupled thermo-hydro-mechanical-chemical (THMC) processes in geologic formations in support of the performance assessment for underground storage of radioactive waste. One of the research tasks, initiated in 2004 by the U.S. Department of Energy (DOE), addresses the long-term impact of geomechanical and geochemical processes on the flow conditions near waste emplacement tunnels. Within this task, four international research teams conduct predictive analysismore » of the coupled processes in two generic repositories, using multiple approaches and different computer codes. Below, we give an overview of the research task and report its current status.« less

  13. Application of Reservoir Flow Simulation Integrated with Geomechanics in Unconventional Tight Play

    NASA Astrophysics Data System (ADS)

    Lin, Menglu; Chen, Shengnan; Mbia, Ernest; Chen, Zhangxing

    2018-01-01

    Multistage hydraulic fracturing techniques, combined with horizontal drilling, have enabled commercial production from the vast reserves of unconventional tight formations. During hydraulic fracturing, fracturing fluid and proppants are pumped into the reservoir matrix to create the hydraulic fractures. Understanding the propagation mechanism of hydraulic fractures is essential to estimate their properties, such as half-length. In addition, natural fractures are often present in tight formations, which might be activated during the fracturing process and contribute to the post-stimulation well production rates. In this study, reservoir simulation is integrated with rock geomechanics to predict the well post-stimulation productivities. Firstly, a reservoir geological model is built based on the field data collected from the Montney formation in the Western Canadian Sedimentary Basin. The hydraulic fracturing process is then simulated through an integrated approach of fracturing fluid injection, rock geomechanics, and tensile failure criteria. In such a process, the reservoir pore pressure increases with a continuous injection of the fracturing fluid and proppants, decreasing the effective stress exerted on the rock matrix accordingly as the overburden pressure remains constant. Once the effective stress drops to a threshold value, tensile failure of the reservoir rock occurs, creating hydraulic fractures in the formation. The early production history of the stimulated well is history-matched to validate the predicted fracture geometries (e.g., half-length) generated from the fracturing simulation process. The effects of the natural fracture properties and well bottom-hole pressures on well productivity are also studied. It has been found that nearly 40% of hydraulic fractures propagate in the beginning stage (the pad step) of the fracturing schedule. In addition, well post-stimulation productivity will increase significantly if the natural fractures are propped or

  14. Permeability of three-dimensional rock masses containing geomechanically-grown anisotropic fracture networks

    NASA Astrophysics Data System (ADS)

    Thomas, R. N.; Ebigbo, A.; Paluszny, A.; Zimmerman, R. W.

    2016-12-01

    The macroscopic permeability of 3D anisotropic geomechanically-generated fractured rock masses is investigated. The explicitly computed permeabilities are compared to the predictions of classical inclusion-based effective medium theories, and to the permeability of networks of randomly oriented and stochastically generated fractures. Stochastically generated fracture networks lack features that arise from fracture interaction, such as non-planarity, and termination of fractures upon intersection. Recent discrete fracture network studies include heuristic rules that introduce these features to some extent. In this work, fractures grow and extend under tension from a finite set of initial flaws. The finite element method is used to compute displacements, and modal stress intensity factors are computed around each fracture tip using the interaction integral accumulated over a set of virtual discs. Fracture apertures emerge as a result of simulations that honour the constraints of stress equilibrium and mass conservation. The macroscopic permeabilities are explicitly calculated by solving the local cubic law in the fractures, on an element-by-element basis, coupled to Darcy's law in the matrix. The permeabilities are then compared to the estimates given by the symmetric and asymmetric versions of the self-consistent approximation, which, for randomly fractured volumes, were previously demonstrated to be most accurate of the inclusion-based effective medium methods (Ebigbo et al., Transport in Porous Media, 2016). The permeabilities of several dozen geomechanical networks are computed as a function of density and in situ stresses. For anisotropic networks, we find that the asymmetric and symmetric self-consistent methods overestimate the effective permeability in the direction of the dominant fracture set. Effective permeabilities that are more strongly dependent on the connectivity of two or more fracture sets are more accurately captured by the effective medium models.

  15. Preface to the Special Issue on TOUGH Symposium 2015

    NASA Astrophysics Data System (ADS)

    Blanco-Martín, Laura

    2017-11-01

    The TOUGH Symposium 2015 was held in Berkeley, California, September 28-30, 2015. The TOUGH family of codes, developed at the Energy Geosciences Division of Lawrence Berkeley National Laboratory (LBNL), is a suite of computer programs for the simulation of multiphase and multicomponent fluid and heat flows in porous and fractured media with applications in many geosciences fields, such as geothermal reservoir engineering, nuclear waste disposal, geological carbon sequestration, oil and gas reservoirs, gas hydrate research, vadose zone hydrology and environmental remediation. Since the first release in the 1980s, many modifications and enhancements have been continuously made to TOUGH and its various descendants (iTOUGH2, TOUGH+, TOUGH-MP, TOUGHREACT, TOUGH+HYDRATE, TMVOC...), at LBNL and elsewhere. Today, these codes are used worldwide in academia, government organizations and private companies in problems involving coupled hydrological, thermal, biogeochemical and geomechanical processes. The Symposia, organized every 2-3 years, bring together developers and users for an open exchange on recent code enhancements and applications. In 2015, the Symposium was attended by one hundred participants, representing thirty-four nationalities. This Special Issue in Computers & Geosciences gathers extended versions of selected Symposium proceedings related to (i) recent enhancements to the TOUGH family of codes and (ii) coupled flow and geomechanics processes modeling.

  16. Eight Key Issues for the White House Conference on Library and Information Services.

    ERIC Educational Resources Information Center

    American Society for Information Science, Washington, DC.

    Presented as a public service in anticipation of the October 1979 White House Conference on Library and Information Services, the eight papers in this booklet call attention to the key issues which the American Society for Information Science (ASIS) believes have developed from proliferating information and for technological advances. Each of the…

  17. Towards optimised information about clinical trials; identification and validation of key issues in collaboration with cancer patient advocates.

    PubMed

    Dellson, P; Nilbert, M; Bendahl, P-O; Malmström, P; Carlsson, C

    2011-07-01

    Clinical trials are crucial to improve cancer treatment but recruitment is difficult. Optimised patient information has been recognised as a key issue. In line with the increasing focus on patients' perspectives in health care, we aimed to study patients' opinions about the written information used in three clinical trials for breast cancer. Primary data collection was done in focus group interviews with breast cancer patient advocates. Content analysis identified three major themes: comprehensibility, emotions and associations, and decision making. Based on the advocates' suggestions for improvements, 21 key issues were defined and validated through a questionnaire in an independent group of breast cancer patient advocates. Clear messages, emotionally neutral expressions, careful descriptions of side effects, clear comparisons between different treatment alternatives and information about the possibility to discontinue treatment were perceived as the most important issues. Patients' views of the information in clinical trials provide new insights and identify key issues to consider in optimising future written information and may improve recruitment to clinical cancer trials. © 2010 Blackwell Publishing Ltd.

  18. Identification of Key Issues in Adopting a Web 2.0 E-Portfolio Strategy

    ERIC Educational Resources Information Center

    McKenna, Gary F.; Stansfield, Mark H.

    2013-01-01

    The purpose of the paper is to identify key issues relating to best practice and sustainability in Web 2.0 as an e-Learning strategy for supporting e-portfolios in Higher Education. A practical guidelines framework was developed for best practices, which can be justified by the lack of available frameworks in the e-Learning literature. A…

  19. Pressure prediction in non-uniaxial settings based on field data and geomechanical modeling: a well example

    NASA Astrophysics Data System (ADS)

    Lockhart, L. P.; Flemings, P. B.; Nikolinakou, M. A.; Heidari, M.

    2016-12-01

    We apply a new pressure prediction approach that couples sonic velocity data, geomechanical modeling, and a critical state soil model to estimate pore pressure from wellbore data adjacent to a salt body where the stress field is complex. Specifically, we study pressure and stress in front of the Mad Dog salt body, in the Gulf of Mexico. Because of the loading from the salt, stresses are not uniaxial; the horizontal stress is elevated, leading to higher mean and shear stresses. For the Mad Dog field, we develop a relationship between velocity and equivalent effective stress, in order to account for both the mean and shear stress effect on pore pressure. We obtain this equivalent effective stress using a geomechanical model of the Mad Dog field. We show that the new approach improves pressure prediction in areas near salt where mean and shear stress are different than the control well. Our methodology and results show that pore pressure is driven by a combination of mean stress and shear stress, and highlight the importance of shear-induced pore pressures. Furthermore, the impact of our study extends beyond salt bodies; the methodology and gained insights are applicable to geological environments around the world with a complex geologic history, where the stress state is not uniaxial (fault zones, anticlines, synclines, continental margins, etc.).

  20. Fluid Flow Simulation For CO2-EOR and Sequestration Utilizing Geomechanical Constraints - Teapot Dome Oil Field, Wyoming

    NASA Astrophysics Data System (ADS)

    Chiaramonte, L.; Zoback, M. D.; Friedmann, J.; Stamp, V.

    2007-12-01

    Mature oil and gas reservoirs are attractive targets for geological sequestration of CO2 because of their potential storage capacities and the possible cost offsets from enhanced oil recovery (EOR). In this work we develop a 3D reservoir model and fluid flow simulation of the Tensleep Formation using geomechanical constraints to evaluate the feasibility of a CO2-EOR injection project at Teapot Dome Oil Field, WY. The objective of this work is to model the migration of the injected CO2 as well as to obtain limits on the rates and volumes of CO2 that can be injected without compromising seal integrity. Teapot Dome is an elongated asymmetrical, basement-cored anticline with a north-northwest axis. It is part of the Salt Creek structural trend, located in the southwestern edge of the Powder River Basin. The Tensleep Fm. in this area consists of interdune deposits such as eolian sandstones, sabkha carbonates, evaporites (mostly anhydrite), and some very low permeability dolomicrites. The average porosity is 0.10 ranging from 0.05-0.20. The average permeability is 30 mD, ranging from 10 - 100 mD. The average reservoir thickness is 50 ft. The reservoir has strong aquifer drive. In the area under study, the Tensleep Fm. has its structural crest at 1675 m. It presents a 3-way closure trap against a NE-SW fault to the north. We previously carried out a geomechanical stability analysis and found this fault to be able to support the increase in pressure due to the CO2 to be injected, even if the structure was "filled-to-spill". In this work we combine our previous geomechanical analysis, geostatistical reservoir modeling and fluid flow simulations to investigate critical questions regarding the feasibility of a CO2-EOR project in the Tensleep Fm. The analysis takes into consideration the initial trapping and sealing mechanisms of the reservoir, the consequences of past and present oil production on the initial properties, and the potential effect of CO2 injection on both the

  1. Understanding Price Elasticities to Inform Public Health Research and Intervention Studies: Key Issues

    PubMed Central

    Nghiem, Nhung; Genç, Murat; Blakely, Tony

    2013-01-01

    Pricing policies such as taxes and subsidies are important tools in preventing and controlling a range of threats to public health. This is particularly so in tobacco and alcohol control efforts and efforts to change dietary patterns and physical activity levels as a means of addressing increases in noncommunicable diseases. To understand the potential impact of pricing policies, it is critical to understand the nature of price elasticities for consumer products. For example, price elasticities are key parameters in models of any food tax or subsidy that aims to quantify health impacts and cost-effectiveness. We detail relevant terms and discuss key issues surrounding price elasticities to inform public health research and intervention studies. PMID:24028228

  2. Geomechanical Assessments of Simultaneous Operation in the Case of Transition from Open Pit to Underground Mine in Vietnam

    NASA Astrophysics Data System (ADS)

    Niedbalski, Zbigniew; Nguyen, Phu Minh Vuong; Widzyk-Capehart, Eleonora

    2018-03-01

    Nowadays, for a number of reasons, many open pit mines are considering a transition from Open Pit (OP) to Underground (UG) to remain competitive. In OP-UG transition, UG operation is operated simultaneously with the OP operation for a certain period of time. Guidelines for the simultaneous operation of OP and UG are very difficult to establish, as there are very few case studies available. Yet, because of the OP-UG interactions; the operation has a higher safety, technical and management requirements than the OP or UG methods when considered separately. In Vietnam, Cao Son is one of many OP mines, which decided to change the operational system from OP to UG. Simultaneous operation started in 2015 and will be conducted until 2030 when the OP mine Cao Son ends its mining activities. In this paper, selected geomechanical considerations of the simultaneous operation are presented. A number of numerical modelling calculations using finitedifference software with code FLAC were carried out for calibration process, slope stability analysis and the OP-UG interaction analysis for the Cao Son - Khe Cham II-IV mine. Based on the results obtained from numerical modelling, the geomechanical assessments of simultaneous operation Cao Son - Khe Cham II-IV are discussed in this paper.

  3. Role of Geomechanics in Assessing the Feasibility of CO2 Sequestration in Depleted Hydrocarbon Sandstone Reservoirs

    NASA Astrophysics Data System (ADS)

    Fang, Zhi; Khaksar, Abbas

    2013-05-01

    Carbon dioxide (CO2) sequestration in depleted sandstone hydrocarbon reservoirs could be complicated by a number of geomechanical problems associated with well drilling, completions, and CO2 injection. The initial production of hydrocarbons (gas or oil) and the resulting pressure depletion as well as associated reduction in horizontal stresses (e.g., fracture gradient) narrow the operational drilling mud weight window, which could exacerbate wellbore instabilities while infill drilling. Well completions (casing, liners, etc.) may experience solids flowback to the injector wells when injection is interrupted due to CO2 supply or during required system maintenance. CO2 injection alters the pressure and temperature in the near wellbore region, which could cause fault reactivation or thermal fracturing. In addition, the injection pressure may exceed the maximum sustainable storage pressure, and cause fracturing and fault reactivation within the reservoirs or bounding formations. A systematic approach has been developed for geomechanical assessments for CO2 storage in depleted reservoirs. The approach requires a robust field geomechanical model with its components derived from drilling and production data as well as from wireline logs of historical wells. This approach is described in detail in this paper together with a recent study on a depleted gas field in the North Sea considered for CO2 sequestration. The particular case study shows that there is a limitation on maximum allowable well inclinations, 45° if aligning with the maximum horizontal stress direction and 65° if aligning with the minimum horizontal stress direction, beyond which wellbore failure would become critical while drilling. Evaluation of sanding risks indicates no sand control installations would be needed for injector wells. Fracturing and faulting assessments confirm that the fracturing pressure of caprock is significantly higher than the planned CO2 injection and storage pressures for an ideal

  4. Practical issues in quantum-key-distribution postprocessing

    NASA Astrophysics Data System (ADS)

    Fung, Chi-Hang Fred; Ma, Xiongfeng; Chau, H. F.

    2010-01-01

    Quantum key distribution (QKD) is a secure key generation method between two distant parties by wisely exploiting properties of quantum mechanics. In QKD, experimental measurement outcomes on quantum states are transformed by the two parties to a secret key. This transformation is composed of many logical steps (as guided by security proofs), which together will ultimately determine the length of the final secret key and its security. We detail the procedure for performing such classical postprocessing taking into account practical concerns (including the finite-size effect and authentication and encryption for classical communications). This procedure is directly applicable to realistic QKD experiments and thus serves as a recipe that specifies what postprocessing operations are needed and what the security level is for certain lengths of the keys. Our result is applicable to the BB84 protocol with a single or entangled photon source.

  5. A unified approach to fluid-flow, geomechanical, and seismic modelling

    NASA Astrophysics Data System (ADS)

    Yarushina, Viktoriya; Minakov, Alexander

    2016-04-01

    The perturbations of pore pressure can generate seismicity. This is supported by observations from human activities that involve fluid injection into rocks at high pressure (hydraulic fracturing, CO2 storage, geothermal energy production) and natural examples such as volcanic earthquakes. Although the seismic signals that emerge during geotechnical operations are small both in amplitude and duration when compared to natural counterparts. A possible explanation for the earthquake source mechanism is based on a number of in situ stress measurements suggesting that the crustal rocks are close to its plastic yield limit. Hence, a rapid increase of the pore pressure decreases the effective normal stress, and, thus, can trigger seismic shear deformation. At the same time, little attention has been paid to the fact that the perturbation of fluid pressure itself represents an acoustic source. Moreover, non-double-couple source mechanisms are frequently reported from the analysis of microseismicity. A consistent formulation of the source mechanism describing microseismic events should include both a shear and isotropic component. Thus, improved understanding of the interaction between fluid flow and seismic deformation is needed. With this study we aim to increase the competence in integrating real-time microseismic monitoring with geomechanical modelling such that there is a feedback loop between monitored deformation and stress field modelling. We propose fully integrated seismic, geomechanical and reservoir modelling. Our mathematical formulation is based on fundamental set of force balance, mass balance, and constitutive poro-elastoplastic equations for two-phase media consisting of deformable solid rock frame and viscous fluid. We consider a simplified 1D modelling setup for consistent acoustic source and wave propagation in poro-elastoplastic media. In this formulation the seismic wave is generated due to local changes of the stress field and pore pressure induced by

  6. A review of nuclear thermal propulsion carbide fuel corrosion and key issues

    NASA Technical Reports Server (NTRS)

    Pelaccio, Dennis G.; El-Genk, Mohamed S.

    1994-01-01

    Corrosion (mass loss) of carbide nuclear fuels due to their exposure to hot hydrogen in nuclear thermal propulsion engine systems greatly impacts the performance, thrust-to-weight and life of such systems. This report provides an overview of key issues and processes associated with the corrosion of carbide materials. Additionally, past pertinent development reactor test observations, as well as related experimental work and analysis modeling efforts are reviewed. At the conclusion, recommendations are presented, which provide the foundation for future corrosion modeling and verification efforts.

  7. Scaling up in international health: what are the key issues?

    PubMed

    Mangham, Lindsay J; Hanson, Kara

    2010-03-01

    The term 'scaling up' is now widely used in the international health literature, though it lacks an agreed definition. We review what is meant by scaling up in the context of changes in international health and development over the last decade. We argue that the notion of scaling up is primarily used to describe the ambition or process of expanding the coverage of health interventions, though the term has also referred to increasing the financial, human and capital resources required to expand coverage. We discuss four pertinent issues in scaling up the coverage of health interventions: the costs of scaling up coverage; constraints to scaling up; equity and quality concerns; and key service delivery issues when scaling up. We then review recent progress in scaling up the coverage of health interventions. This includes a considerable increase in the volume of aid, accompanied by numerous new health initiatives and financing mechanisms. There have also been improvements in health outcomes and some examples of successful large-scale programmes. Finally, we reflect on the importance of obtaining a better understanding of how to deliver priority health interventions at scale, the current emphasis on health system strengthening and the challenges of sustaining scaling up in the prevailing global economic environment.

  8. Geomechanical response to seasonal gas storage in depleted reservoirs: A case study in the Po River basin, Italy

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Castelletto, N.; Ferronato, M.; Gambolati, G.; Janna, C.; Cairo, E.; Marzorati, D.; Colombo, D.; Ferretti, A.; Bagliani, A.; Bottazzi, F.

    2011-06-01

    Underground gas storage (UGS) in depleted hydrocarbon reservoirs is a strategic practice to cope with the growing energy demand and occurs in many places in Europe and North America. In response to summer gas injection and winter gas withdrawal the reservoir expands and contracts essentially elastically as a major consequence of the fluid (gas and water) pore pressure fluctuations. Depending on a number of factors, including the reservoir burial depth, the difference between the largest and the smallest gas pore pressure, and the geomechanical properties of the injected formation and the overburden, the porous medium overlying the reservoir is subject to three-dimensional deformation with the related cyclic motion of the land surface being both vertical and horizontal. We present a methodology to evaluate the environmental impact of underground gas storage and sequestration from the geomechanical perspective, particularly in relation to the ground surface displacements. Long-term records of injected and removed gas volume and fluid pore pressure in the "Lombardia" gas field, northern Italy, are available together with multiyear detection of vertical and horizontal west-east displacement of the land surface above the reservoir by an advanced permanent scatterer interferometric synthetic aperture radar (PSInSAR) analysis. These data have been used to calibrate a 3-D fluid-dynamic model and develop a 3-D transversally isotropic geomechanical model. The latter has been successfully implemented and used to reproduce the vertical and horizontal cyclic displacements, on the range of 8-10 mm and 6-8 mm, respectively, measured between 2003 and 2007 above the reservoir where a UGS program has been underway by Stogit-Eni S.p.A. since 1986 following a 5 year field production life. Because of the great economical interest to increase the working gas volume as much as possible, the model addresses two UGS scenarios where the gas pore overpressure is pushed from the current 103

  9. Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies (Final Report)

    EPA Science Inventory

    EPA announced the availability of the final report, Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies. This report summarizes some of the recent progress in characterizing uncertainty and variability in physi...

  10. Geomechanical Behaviors of Laboratory-Formed Non-Cementing Hydrate-Bearing Sediments

    NASA Astrophysics Data System (ADS)

    Seol, Y.

    2015-12-01

    Natural hydrate-bearing sediments (HBS) have been known to exist with non-cementing pore habits, i.e., pore-filling, load-bearing, or patchy type. However, few laboratory studies have been conducted to characterize geomechanical behaviors of non-cementing CH4-HBS, which are of great importance in engineering the process of drilling and gas production in natural hydrate reservoir. In this study, we conducted multi-stage drained triaxial tests on laboratory synthesized CH4-HBS samples, which were formed in sand-clay mixtures (5%wt kaolinite) to have non-cementing habits. Three different effective confining stresses, σ3' = 0.69, 1.38, and 2.76 MPa, were applied on the HBS with the hydrate saturation, Sh, in the range of 0 to ~ 40%. The result confirms that the strength and stiffness of HBS increases with effective confining stress and hydrate saturation. It is also demonstrated that when compared to the cementing HBS, the non-cementing HBS has lower strength and cohesion, owing to less inter-particle adhesion effects from non-cementing hydrate.

  11. Impacts on non-human biota from a generic geological disposal facility for radioactive waste: some key assessment issues.

    PubMed

    Robinson, C A; Smith, K L; Norris, S

    2010-06-01

    This paper provides an overview of key issues associated with the application of currently available biota dose assessment methods to consideration of potential environmental impacts from geological disposal facilities. It explores philosophical, methodological and practical assessment issues and reviews the implications of test assessment results in the context of recent and on-going challenges and debates.

  12. Geological and geomechanical properties of the carbonate rocks at the eastern Black Sea Region (NE Turkey)

    NASA Astrophysics Data System (ADS)

    Ersoy, Hakan; Yalçinalp, Bülent; Arslan, Mehmet; Babacan, Ali Erden; Çetiner, Gözde

    2016-11-01

    Turkey located in the Alpine-Himalayan Mountain Belt has 35% of the natural stone reserves of the world and has good quality marble, limestone, travertine and onyx reserves especially in the western regions of the country. The eastern Black Sea Region with a 1.4 million meters cubes reserve has a little role on the natural stone production in the country. For this reason, this paper deals with investigation on the potential of carbonate stone in the region and determination of the geological and geo-mechanical properties of these rocks in order to provide economic contribution to the national economy. While the study sites are selected among the all carbonate rock sites, the importance as well as the representative of the sites were carefully considered for the region. After representative samples were analyzed for major oxide and trace element compositions to find out petrochemical variations, the experimental program conducted on rock samples for determination of both physical and strength properties of the carbonate rocks. The results of the tests showed that there are significant variations in the geo-mechanical properties of the studied rock groups. The density values vary from 2.48 to 2.70 gr/cm3, water absorption by weight values range from 0.07 to 1.15% and the apparent porosity of the carbonate rocks are between 0.19 and 3.29%. However, the values of the UCS shows variation from 36 to 80 MPa. Tensile and bending strength values range from 3.2 to 7.5 MPa and 6.0-9.2 MPa respectively. Although the onyx samples have the lowest values of apparent porosity and water absorption by weight, these samples do not have the highest values of UCS values owing to occurrence of the micro-cracks. The UCS values of the rock samples were also found after cycling tests However, the limestone samples have less than 5% deterioration after freezing-thawing and wetting-drying tests, but travertine and onyx samples have more than 15% deterioration. Exception of the apparent

  13. Numerical Simulation of Permeability Change in Wellbore Cement Fractures after Geomechanical Stress and Geochemical Reactions Using X-ray Computed Tomography Imaging

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

    Kabilan, Senthil; Jung, Hun Bok; Kuprat, Andrew P.

    X-ray microtomography (XMT) imaging combined with a three-dimensional (3D) computational fluid dynamics (CFD) modeling technique was used to study the effect of geochemical and geomechanical processes on fracture properties in composite Portland cement–basalt caprock core samples. The effect of fluid properties and flow conditions on fracture permeability was numerically studied by using fluids with varying physical properties and simulating different pressure conditions. CFD revealed that the application of geomechanical stress led to increased fluid flow, which resulted in increased fracture permeability. After CO2-reaction, XMT images displayed preferential precipitation of calcium carbonate within the fractures in the cement matrix and lessmore » precipitation in fractures located at the cement–basalt interface. CFD predicted changes in flow characteristics and differences in absolute values of flow properties due to different pressure gradients. CFD was able to highlight the profound effect of fluid properties on flow characteristics and hydraulic properties of fractures. This study demonstrates the applicability of XMT imaging and CFD as powerful tools for characterizing the hydraulic properties of fractures in a number of applications like geologic carbon sequestration and storage, hydraulic fracturing for shale gas production, and enhanced geothermal systems.« less

  14. Development of Performance Dashboards in Healthcare Sector: Key Practical Issues.

    PubMed

    Ghazisaeidi, Marjan; Safdari, Reza; Torabi, Mashallah; Mirzaee, Mahboobeh; Farzi, Jebraeil; Goodini, Azadeh

    2015-10-01

    Static nature of performance reporting systems in health care sector has resulted in inconsistent, incomparable, time consuming, and static performance reports that are not able to transparently reflect a round picture of performance and effectively support healthcare managers' decision makings. So, the healthcare sector needs interactive performance management tools such as performance dashboards to measure, monitor, and manage performance more effectively. The aim of this article was to identify key issues that need to be addressed for developing high-quality performance dashboards in healthcare sector. A literature review was established to search electronic research databases, e-journals collections, and printed journals, books, dissertations, and theses for relevant articles. The search strategy interchangeably used the terms of "dashboard", "performance measurement system", and "executive information system" with the term of "design" combined with operator "AND". Search results (n=250) were adjusted for duplications, screened based on their abstract relevancy and full-text availability (n=147) and then assessed for eligibility (n=40). Eligible articles were included if they had explicitly focused on dashboards, performance measurement systems or executive information systems design. Finally, 28 relevant articles included in the study. Creating high-quality performance dashboards requires addressing both performance measurement and executive information systems design issues. Covering these two fields, identified contents were categorized to four main domains: KPIs development, Data Sources and data generation, Integration of dashboards to source systems, and Information presentation issues. This study implies the main steps to develop dashboards for the purpose of performance management. Performance dashboards developed on performance measurement and executive information systems principles and supported by proper back-end infrastructure will result in

  15. Development of Performance Dashboards in Healthcare Sector: Key Practical Issues

    PubMed Central

    Ghazisaeidi, Marjan; Safdari, Reza; Torabi, Mashallah; Mirzaee, Mahboobeh; Farzi, Jebraeil; Goodini, Azadeh

    2015-01-01

    Background: Static nature of performance reporting systems in health care sector has resulted in inconsistent, incomparable, time consuming, and static performance reports that are not able to transparently reflect a round picture of performance and effectively support healthcare managers’ decision makings. So, the healthcare sector needs interactive performance management tools such as performance dashboards to measure, monitor, and manage performance more effectively. The aim of this article was to identify key issues that need to be addressed for developing high-quality performance dashboards in healthcare sector. Methods: A literature review was established to search electronic research databases, e-journals collections, and printed journals, books, dissertations, and theses for relevant articles. The search strategy interchangeably used the terms of “dashboard”, “performance measurement system”, and “executive information system” with the term of “design” combined with operator “AND”. Search results (n=250) were adjusted for duplications, screened based on their abstract relevancy and full-text availability (n=147) and then assessed for eligibility (n=40). Eligible articles were included if they had explicitly focused on dashboards, performance measurement systems or executive information systems design. Finally, 28 relevant articles included in the study. Results: Creating high-quality performance dashboards requires addressing both performance measurement and executive information systems design issues. Covering these two fields, identified contents were categorized to four main domains: KPIs development, Data Sources and data generation, Integration of dashboards to source systems, and Information presentation issues. Conclusion: This study implies the main steps to develop dashboards for the purpose of performance management. Performance dashboards developed on performance measurement and executive information systems principles and

  16. Experimental and Computational Studies of Coupled Geomechanical and Hydrologic Processes in Wellbore Systems (Invited)

    NASA Astrophysics Data System (ADS)

    Carey, J. W.; Mori, H.; Porter, M. L.; Lewis, K. C.; Kelkar, S.

    2013-12-01

    Potential leakage from wells is an important issue in the protection of groundwater resources, CO2 sequestration, and hydraulic fracturing. The first defense in all of these applications is a properly constructed well with adequate Portland cement that effectively isolates the subsurface. The chief threat for such wells is mechanical disruption of the cement, cement/steel, or cement/caprock interfaces. This can occur through wellbore operations that pressurize/depressurize the steel tubing or create temperature transients (e.g., injection, production, hydraulic fracturing, and mechanical testing) as well as reservoir-scale stresses (e.g., filling or depletion of the reservoir) and tectonic stresses (e.g., the mobility of salt). However, there is relatively limited information available on the hydrologic consequences of such processes. Toward this end, we discuss recent experiments and computational models of coupled geomechanical and hydrologic processes in wellbore systems. Triaxial coreflood experiments with tomography were conducted on synthetic wellbore systems including cement-steel, rock-cement and rock-cement-steel composites. The aim of the experiments was to induce stresses through application of axial loads in order to create defects within the cement or at the cement/steel or cement/rock interface. High injection fluid pressures (supercritical CO2 × brine) were applied to the base of the initially impermeable composites. Mechanical failure resulted in creation of permeability, which was measured as a function of time (allowing for the possibility of Portland cement to deform and modify permeability). In addition, fracture patterns were characterized using x-ray tomography. We used the computer code FEHM to study coupled hydrologic and mechanical processes in the near-wellbore environment. The wellbore model was developed as a wedge within a radially symmetric 3D volume. The grid elements consist of the steel casing, the casing-cement interface, the

  17. International and cross-cultural issues: six key challenges for our professions.

    PubMed

    Marshall, Julie

    2003-01-01

    This paper discusses a number of key challenges facing professionals who work with people who have communication disabilities. The challenges are related to working internationally and in a cross-culturally competent way. Each challenge is discussed, drawing on material from a range of sources, including the papers in the final 2003 edition of FOLIA PHONIATRICA ET LOGOPAEDICA ('International and Cross-Cultural Issues'). The challenges discussed cover how experiences from majority world countries can be used to benefit services elsewhere, 'mainstreaming' commitment to cross-cultural competence, learning from relationships with other professionals, influencing research practice, responding to requests to work internationally and finally, dealing with cultural differences that challenge working practices. Some solutions are suggested and additional questions posed. Copyright 2003 S. Karger AG, Basel

  18. Coupled reservoir-geomechanical analysis of CO2 injection and ground deformations at In Salah, Algeria

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

    Rutqvist, J.; Vasco, D.W.; Myer, L.

    2009-11-01

    In Salah Gas Project in Algeria has been injecting 0.5-1 million tonnes CO{sub 2} per year over the past five years into a water-filled strata at a depth of about 1,800 to 1,900 m. Unlike most CO{sub 2} storage sites, the permeability of the storage formation is relatively low and comparatively thin with a thickness of about 20 m. To ensure adequate CO{sub 2} flow-rates across the low-permeability sand-face, the In Salah Gas Project decided to use long-reach (about 1 to 1.5 km) horizontal injection wells. In an ongoing research project we use field data and coupled reservoir-geomechanical numerical modelingmore » to assess the effectiveness of this approach and to investigate monitoring techniques to evaluate the performance of a CO{sub 2}-injection operation in relatively low permeability formations. Among the field data used are ground surface deformations evaluated from recently acquired satellite-based inferrometry (InSAR). The InSAR data shows a surface uplift on the order of 5 mm per year above active CO{sub 2} injection wells and the uplift pattern extends several km from the injection wells. In this paper we use the observed surface uplift to constrain our coupled reservoir-geomechanical model and conduct sensitivity studies to investigate potential causes and mechanisms of the observed uplift. The results of our analysis indicates that most of the observed uplift magnitude can be explained by pressure-induced, poro-elastic expansion of the 20 m thick injection zone, but there could also be a significant contribution from pressure-induced deformations within a 100 m thick zone of shaly sands immediately above the injection zone.« less

  19. Integrating stimulation practices with geo-mechanical properties in liquid-rich plays of Eagle Ford Shale

    NASA Astrophysics Data System (ADS)

    Yusuf, Ahmed

    Many of the techniques for hydraulically fracturing design were attempted in the liquid-rich Eagle Ford developments. This study shows why different results were observed due to the variation of geomechanical stresses of the rock across a play and related reservoir properties. An optimum treatment for a liquids-rich objective is much different than that for a gas shale due primarily to the multiphase flow and higher viscosities encountered. This study presents a new treatment workflow for liquids-rich window of Eagle Ford Shale. Review and integration of data from multiple sets across the play are used as input to a 3D hydraulic fracture simulator to model key fracture parameters which control production enhancement. These results are then used within a production analysis and forecast, well optimization, and economic model to compare treatment designs with the best placement of proppant to deliver both high initial production and long term ultimate recoveries. A key focus for this workflow is to maximize proppant transport to achieve a continuous - optimum conductive - fracture half length. Often, due to the complexity of unconventional deposition, it is difficult to maintain complete connectivity of a proppant pack back to the wellbore. As a result, much of the potential of the fracture network is lost. Understanding the interaction of a hydraulic fracture and the rock fabric helps with designing this behavior to achieve the best results. These results are used to determine optimum well spacing to effectively develop within a selected reservoir acreage. Currently, numerous wells exist with over two years of production history in much of the Eagle Ford shale formation. Results from this study are used to compare values from field production to demonstrate the importance of employing a diligent workflow in integrating reservoir and operational parameters to the fracture design. A proper understanding and application of hydraulic fracturing modeling is achieved

  20. Using Fully Coupled Hydro-Geomechanical Numerical Test Bed to Study Reservoir Stimulation with Low Hydraulic Pressure

    DOE Data Explorer

    Fu, Pengcheng; Johnson, Scott M.; Carrigan, Charles R.

    2012-01-31

    This paper documents our effort to use a fully coupled hydro-geomechanical numerical test bed to study using low hydraulic pressure to stimulate geothermal reservoirs with existing fracture network. In this low pressure stimulation strategy, fluid pressure is lower than the minimum in situ compressive stress, so the fractures are not completely open but permeability improvement can be achieved through shear dilation. We found that in this low pressure regime, the coupling between the fluid phase and the rock solid phase becomes very simple, and the numerical model can achieve a low computational cost. Using this modified model, we study the behavior of a single fracture and a random fracture network.

  1. The Identification of Key Issues in the Development of Sustainable e-Learning and Virtual Campus Initiatives

    ERIC Educational Resources Information Center

    Stansfield, Mark; Connolly, Thomas; Cartelli, Antonio; Jimoyiannis, Athanassios; Magalhaes, Hugo; Maillet, Katherine

    2009-01-01

    This paper explores a number of key issues that have been identified as being important in the identification and evaluation of best practice within the context of e-learning and virtual campuses. The "Promoting Best Practice in Virtual Campuses" (PBP-VC) project is a two year European Commission Education Audiovisual and Culture…

  2. Numerical Simulation of Permeability Change in Wellbore Cement Fractures after Geomechanical Stress and Geochemical Reactions Using X-ray Computed Tomography Imaging.

    PubMed

    Kabilan, Senthil; Jung, Hun Bok; Kuprat, Andrew P; Beck, Anthon N; Varga, Tamas; Fernandez, Carlos A; Um, Wooyong

    2016-06-21

    X-ray microtomography (XMT) imaging combined with three-dimensional (3D) computational fluid dynamics (CFD) modeling technique was used to study the effect of geochemical and geomechanical processes on fracture permeability in composite Portland cement-basalt caprock core samples. The effect of fluid density and viscosity and two different pressure gradient conditions on fracture permeability was numerically studied by using fluids with varying density and viscosity and simulating two different pressure gradient conditions. After the application of geomechanical stress but before CO2-reaction, CFD revealed fluid flow increase, which resulted in increased fracture permeability. After CO2-reaction, XMT images displayed preferential precipitation of calcium carbonate within the fractures in the cement matrix and less precipitation in fractures located at the cement-basalt interface. CFD estimated changes in flow profile and differences in absolute values of flow velocity due to different pressure gradients. CFD was able to highlight the profound effect of fluid viscosity on velocity profile and fracture permeability. This study demonstrates the applicability of XMT imaging and CFD as powerful tools for characterizing the hydraulic properties of fractures in a number of applications like geologic carbon sequestration and storage, hydraulic fracturing for shale gas production, and enhanced geothermal systems.

  3. Strategic management and organizational behavior in dental education: reflections on key issues in an environment of change.

    PubMed

    Dunning, David G; Durham, Timothy M; Lange, Brian M; Aksu, Mert N

    2009-06-01

    With issues such as shrinking revenue, access to care, faculty workloads, and graying faculty, dental schools are faced with difficult challenges that fall to dental school deans to manage. Do dental school deans have the organizational skill sets and ethical frameworks necessary to address the challenges now facing dental schools? The purpose of this article is to pose questions and suggestions regarding some of the key issues in dental colleges today and to stimulate discussion in the dental community about needed changes in dental education.

  4. Stress field sensitivity analysis within Mesozoic successions in the Swiss Alpine foreland using 3-D-geomechanical-numerical models

    NASA Astrophysics Data System (ADS)

    Reiter, Karsten; Hergert, Tobias; Heidbach, Oliver

    2016-04-01

    The in situ stress conditions are of key importance for the evaluation of radioactive waste repositories. In stage two of the Swiss site selection program, the three siting areas of high-level radioactive waste are located in the Alpine foreland in northern Switzerland. The sedimentary succession overlays the basement, consisting of variscan crystalline rocks as well as partly preserved Permo-Carboniferous deposits in graben structures. The Mesozoic sequence represents nearly the complete era and is covered by Cenozoic Molasse deposits as well as Quaternary sediments, mainly in the valleys. The target horizon (designated host rock) is an >100 m thick argillaceous Jurassic deposit (Opalinus Clay). To enlighten the impact of site-specific features on the state of stress within the sedimentary succession, 3-D-geomechanical-numerical models with elasto-plastic rock properties are set up for three potential siting areas. The lateral extent of the models ranges between 12 and 20 km, the vertical extent is up to a depth of 2.5 or 5 km below sea level. The sedimentary sequence plus the basement are separated into 10 to 14 rock mechanical units. The Mesozoic succession is intersected by regional fault zones; two or three of them are present in each model. The numerical problem is solved with the finite element method with a resolution of 100-150 m laterally and 10-30 m vertically. An initial stress state is established for all models taking into account the depth-dependent overconsolidation ratio in Opalinus Clay in northern Switzerland. The influence of topography, rock properties, friction on the faults as well as the impact of tectonic shortening on the state of stress is investigated. The tectonic stress is implemented with lateral displacement boundary conditions, calibrated on stress data that are compiled in Northern Switzerland. The model results indicate that the stress perturbation by the topography is significant to depths greater than the relief contrast. The

  5. Key issues in human resource planning for home support workers in Canada.

    PubMed

    Keefe, Janice M; Knight, Lucy; Martin-Matthews, Anne; Légaré, Jacques

    2011-01-01

    This paper is a synthesis of research on recruitment and retention challenges for home support workers (HSWs) in Canada. Home support workers (HSWs) provide needed support with personal care and daily activities to older persons living in the community. Literature (peer reviewed, government, and non-government documents) published in the past decade was collected from systematic data base searches between January and September 2009, and yielded over 100 references relevant to home care human resources for older Canadians. Four key human resource issues affecting HSWs were identified: compensation, education and training, quality assurance, and working conditions. To increase the workforce and retain skilled employees, employers can tailor their marketing strategies to specific groups, make improvements in work environment, and learn about what workers value and what attracts them to home support work. Understanding these HR issues for HSWs will improve recruitment and retention strategies for this workforce by helping agencies to target their limited resources. Given the projected increase in demand for these workers, preparations need to begin now and consider long-term strategies involving multiple policy areas, such as health and social care, employment, education, and immigration.

  6. Family-friendliness in business as a key issue for the future.

    PubMed

    Stutzer, Erich

    2012-01-01

    These days family-friendliness is a key issue for the future of businesses. Investments in a family conscious personnel policy are considered as forward-looking decisions in companies. This happens against the background of a sustainable personnel policy in times of a decrease in the number of employable persons, an increasing shortage of skilled workers and an ageing workforce. Family-friendly working conditions are becoming a key factor in the competition for staff. When choosing an employer, family-friendliness has become a crucial topic. Employment participation and skills of women, especially of mothers, have greatly increased. To facilitate the realisation of their wish to return to paid employment, however, measures to reconcile work and family are required. Family-conscious measures have been proven to lead to higher employee productivity. Job satisfaction and motivation of employees and accumulation of human capital increase, absenteeism declines, the return of investment rises. Fields of activity for family-friendly measures in companies range from working arrangements, parental leave and re-entry programmes and various child care offers to services for families. In connection with the demographic development the demand for a better reconciliation of work and elder care should in future become ever more important, just as the upkeep of the occupational skills and working capacity of an ageing workforce. Family-friendliness has to become an integral part of corporate culture.

  7. Strain Rate Dependency of Fracture Toughness, Energy Release Rate and Geomechanical Attributes of Select Indian Shales

    NASA Astrophysics Data System (ADS)

    Mahanta, B.; Vishal, V.; Singh, T. N.; Ranjith, P.

    2016-12-01

    In addition to modern improved technology, it requires detailed understanding of rock fractures for the purpose of enhanced energy extraction through hydraulic fracturing of gas shales and geothermal energy systems. The understanding of rock fracture behavior, patterns and properties such as fracture toughness; energy release rate; strength and deformation attributes during fracturing hold significance. Environmental factors like temperature, pressure, humidity, water vapor and experimental condition such as strain rate influence the estimation of these properties. In this study, the effects of strain rates on fracture toughness, energy release rate as well as geomechanical properties like uniaxial compressive strength, Young's modulus, failure strain, tensile strength, and brittleness index of gas shales were investigated. In addition to the rock-mechanical parameters, the fracture toughness and the energy release rates were measured for three different modes viz. mode I, mixed mode (I-II) and mode II. Petrographic and X-ray diffraction (XRD) analyses were performed to identify the mineral composition of the shale samples. Scanning electron microscope (SEM) analyses were conducted to have an insight about the strain rate effects on micro-structure of the rock. The results suggest that the fracture toughness; the energy release rate as well as other geomechanical properties are a function of strain rates. At high strain rates, the strength and stiffness of shale increases which in turn increases the fracture toughness and the energy release rate of shale that may be due to stress redistribution during grain fracturing. The fracture toughness and the strain energy release rates for all the modes (I/I-II/II) are comparable at lower strain rates, but they vary considerably at higher strain rates. In all the cases, mode I and mode II fracturing requires minimum and maximum applied energy, respectively. Mode I energy release rate is maximum, compared to the other modes.

  8. Fertility Preservation: A Key Survivorship Issue for Young Women with Cancer

    PubMed Central

    Angarita, Ana Milena; Johnson, Cynae A.; Fader, Amanda Nickles; Christianson, Mindy S.

    2016-01-01

    Fertility preservation in the young cancer survivor is recognized as a key survivorship issue by the American Society of Clinical Oncology and the American Society of Reproductive Medicine. Thus, health-care providers should inform women about the effects of cancer therapy on fertility and should discuss the different fertility preservation options available. It is also recommended to refer women expeditiously to a fertility specialist in order to improve counseling. Women’s age, diagnosis, presence of male partner, time available, and preferences regarding use of donor sperm influence the selection of the appropriate fertility preservation option. Embryo and oocyte cryopreservation are the standard techniques used while ovarian tissue cryopreservation is new, yet promising. Despite the importance of fertility preservation for cancer survivors’ quality of life, there are still communication and financial barriers faced by women who wish to pursue fertility preservation. PMID:27200291

  9. Key issues review: evolution on rugged adaptive landscapes

    NASA Astrophysics Data System (ADS)

    Obolski, Uri; Ram, Yoav; Hadany, Lilach

    2018-01-01

    Adaptive landscapes represent a mapping between genotype and fitness. Rugged adaptive landscapes contain two or more adaptive peaks: allele combinations with higher fitness than any of their neighbors in the genetic space. How do populations evolve on such rugged landscapes? Evolutionary biologists have struggled with this question since it was first introduced in the 1930s by Sewall Wright. Discoveries in the fields of genetics and biochemistry inspired various mathematical models of adaptive landscapes. The development of landscape models led to numerous theoretical studies analyzing evolution on rugged landscapes under different biological conditions. The large body of theoretical work suggests that adaptive landscapes are major determinants of the progress and outcome of evolutionary processes. Recent technological advances in molecular biology and microbiology allow experimenters to measure adaptive values of large sets of allele combinations and construct empirical adaptive landscapes for the first time. Such empirical landscapes have already been generated in bacteria, yeast, viruses, and fungi, and are contributing to new insights about evolution on adaptive landscapes. In this Key Issues Review we will: (i) introduce the concept of adaptive landscapes; (ii) review the major theoretical studies of evolution on rugged landscapes; (iii) review some of the recently obtained empirical adaptive landscapes; (iv) discuss recent mathematical and statistical analyses motivated by empirical adaptive landscapes, as well as provide the reader with instructions and source code to implement simulations of evolution on adaptive landscapes; and (v) discuss possible future directions for this exciting field.

  10. EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (External Review Draft)

    EPA Science Inventory

  1. A Discussion with Sandy O'Sullivan about Key Issues for the Australian Indigenous Studies Learning and Teaching Network

    ERIC Educational Resources Information Center

    Barney, Katelyn

    2014-01-01

    This article takes the form of an interview with Sandy O'Sullivan, who is a partner on the Australian Indigenous Studies Learning and Teaching Network, about key issues that have arisen through Network discussions. She is a Wiradjuri woman and a Senior Aboriginal researcher at the Batchelor Institute of Indigenous Tertiary Education. O'Sullivan…

  2. Work Keys USA.

    ERIC Educational Resources Information Center

    Work Keys USA, 1998

    1998-01-01

    "Work Keys" is a comprehensive program for assessing and teaching workplace skills. This serial "special issue" features 18 first-hand reports on Work Keys projects in action in states across North America. They show how the Work Keys is helping businesses and educators solve the challenge of building a world-class work force.…

  3. Impacts of variability in geomechanical properties on hydrate bearing sediment responses

    NASA Astrophysics Data System (ADS)

    Lin, J. S.; Uchida, S.; Choi, J. H.; Seol, Y.

    2017-12-01

    Hydrate bearing sediments (HBS) may become unstable during the gas production operation, or from natural processes such as change in the landform or temperature. The geomechanical modeling is a rational way to assess HBS stability regardless of the process involved. At the present time, such modeling is laced with uncertainties. The uncertainties come from many sources that include the adequacy of a modeling framework to accurately project the response of HBS, the gap in the available field information, and the variability in the laboratory test results from limited samples. For a reasonable stability assessment, the impact of the various uncertainties have to be addressed. This study looks into one particular aspect of the uncertainty, namely, the uncertainty caused by the scatter in the laboratory tests and the ability of a constitutive model to adequately represent them. Specifically this study focuses on the scatter in the results from laboratory tests on high quality pressured core samples from a marine site, and use a critical state constitutive model to represent them. The study investigates how the HBS responses shift when the parameters of the constitutive model are varied to reflect the different aspects of experimental results. Also investigated are impacts on the responses by altering certain formulations of the constitutive model to suit particular sets of results.

  4. Ten key issues in modern flow chemistry.

    PubMed

    Wegner, Jens; Ceylan, Sascha; Kirschning, Andreas

    2011-04-28

    Ten essentials of synthesis in the flow mode, a new enabling technology in organic chemistry, are highlighted as flashlighted providing an insight into current and future issues and developments in this field. © The Royal Society of Chemistry 2011

  5. Using Eight Key Questions as an Inquiry-Based Framework for Ethical Reasoning Issues in a General Education Earth Systems and Climate Change Course

    NASA Astrophysics Data System (ADS)

    Johnson, E. A.; Ball, T. C.

    2014-12-01

    An important objective in general education geoscience courses is to help students evaluate social and ethical issues based upon scientific knowledge. It can be difficult for instructors trained in the physical sciences to design effective ways of including ethical issues in large lecture courses where whole-class discussions are not practical. The Quality Enhancement Plan for James Madison University, "The Madison Collaborative: Ethical Reasoning in Action," (http://www.jmu.edu/mc/index.shtml) has identified eight key questions to be used as a framework for developing ethical reasoning exercises and evaluating student learning. These eight questions are represented by the acronym FOR CLEAR and are represented by the concepts of Fairness, Outcomes, Responsibilities, Character, Liberty, Empathy, Authority, and Rights. In this study, we use the eight key questions as an inquiry-based framework for addressing ethical issues in a 100-student general education Earth systems and climate change course. Ethical reasoning exercises are presented throughout the course and range from questions of personal behavior to issues regarding potential future generations and global natural resources. In the first few exercises, key questions are identified for the students and calibrated responses are provided as examples. By the end of the semester, students are expected to identify key questions themselves and justify their own ethical and scientific reasoning. Evaluation rubrics are customized to this scaffolding approach to the exercises. Student feedback and course data will be presented to encourage discussion of this and other approaches to explicitly incorporating ethical reasoning in general education geoscience courses.

  6. Fracture Propagation, Fluid Flow, and Geomechanics of Water-Based Hydraulic Fracturing in Shale Gas Systems and Electromagnetic Geophysical Monitoring of Fluid Migration

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

    Kim, Jihoon; Um, Evan; Moridis, George

    2014-12-01

    We investigate fracture propagation induced by hydraulic fracturing with water injection, using numerical simulation. For rigorous, full 3D modeling, we employ a numerical method that can model failure resulting from tensile and shear stresses, dynamic nonlinear permeability, leak-off in all directions, and thermo-poro-mechanical effects with the double porosity approach. Our numerical results indicate that fracture propagation is not the same as propagation of the water front, because fracturing is governed by geomechanics, whereas water saturation is determined by fluid flow. At early times, the water saturation front is almost identical to the fracture tip, suggesting that the fracture is mostlymore » filled with injected water. However, at late times, advance of the water front is retarded compared to fracture propagation, yielding a significant gap between the water front and the fracture top, which is filled with reservoir gas. We also find considerable leak-off of water to the reservoir. The inconsistency between the fracture volume and the volume of injected water cannot properly calculate the fracture length, when it is estimated based on the simple assumption that the fracture is fully saturated with injected water. As an example of flow-geomechanical responses, we identify pressure fluctuation under constant water injection, because hydraulic fracturing is itself a set of many failure processes, in which pressure consistently drops when failure occurs, but fluctuation decreases as the fracture length grows. We also study application of electromagnetic (EM) geophysical methods, because these methods are highly sensitive to changes in porosity and pore-fluid properties due to water injection into gas reservoirs. Employing a 3D finite-element EM geophysical simulator, we evaluate the sensitivity of the crosswell EM method for monitoring fluid movements in shaly reservoirs. For this sensitivity evaluation, reservoir models are generated through the coupled

  7. Effect of Pore Pressure on Slip Failure of an Impermeable Fault: A Coupled Micro Hydro-Geomechanical Model

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Juanes, R.

    2015-12-01

    The geomechanical processes associated with subsurface fluid injection/extraction is of central importance for many industrial operations related to energy and water resources. However, the mechanisms controlling the stability and slip motion of a preexisting geologic fault remain poorly understood and are critical for the assessment of seismic risk. In this work, we develop a coupled hydro-geomechanical model to investigate the effect of fluid injection induced pressure perturbation on the slip behavior of a sealing fault. The model couples single-phase flow in the pores and mechanics of the solid phase. Granular packs (see example in Fig. 1a) are numerically generated where the grains can be either bonded or not, depending on the degree of cementation. A pore network is extracted for each granular pack with pore body volumes and pore throat conductivities calculated rigorously based on geometry of the local pore space. The pore fluid pressure is solved via an explicit scheme, taking into account the effect of deformation of the solid matrix. The mechanics part of the model is solved using the discrete element method (DEM). We first test the validity of the model with regard to the classical one-dimensional consolidation problem where an analytical solution exists. We then demonstrate the ability of the coupled model to reproduce rock deformation behavior measured in triaxial laboratory tests under the influence of pore pressure. We proceed to study the fault stability in presence of a pressure discontinuity across the impermeable fault which is implemented as a plane with its intersected pore throats being deactivated and thus obstructing fluid flow (Fig. 1b, c). We focus on the onset of shear failure along preexisting faults. We discuss the fault stability criterion in light of the numerical results obtained from the DEM simulations coupled with pore fluid flow. The implication on how should faults be treated in a large-scale continuum model is also presented.

  8. Key issues in the management of patients with systemic lupus erythematosus: latest developments and clinical implications

    PubMed Central

    Jordan, Natasha; D’Cruz, David

    2015-01-01

    Systemic lupus erythematous (SLE) is a chronic multisystem disease with significant associated morbidity and mortality. A deeper understanding of the pathogenesis of SLE has led to the development of biologic agents, primarily targeting B cells and others inhibiting costimulatory molecules, type I interferons and cytokines such as interleukin-6. Several of these agents have been studied in clinical trials; some have shown promise while others have yielded disappointing results. Economic and regulatory issues continue to hamper the availability of such therapies for SLE patients. With increasing recognition that recurrent flares of disease activity lead to long-term damage accrual, one of the most important recent developments in patient management has been the concept of treat-to-target in SLE while minimizing patient exposure to excessive corticosteroid and other immunosuppressive therapy. This article reviews these key issues in SLE management, outlining recent developments and clinical implications for patients. PMID:26622325

  9. Executive Summary of the 1999 External Environmental Scan and the Internal Environmental Scan Report Card: Key Issues for Planning.

    ERIC Educational Resources Information Center

    Beachler, Judith

    This document is the second in a series of summary reports outlining Key Issues for Planning useful to staff throughout the Los Rios Community College District (CA) for the 1999-2000 academic year and beyond. The 1999 Environmental Scan of Greater Sacramento provides a comprehensive look at the external environment. It outlines changes in the…

  10. EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (Volume 1) (Interagency Science Discussion Draft)

    EPA Science Inventory

    EPA is releasing the draft report, EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (Volume 1), that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the Geomechanical Model Calibration Using Field Measurements for a Petroleum Reserve

    NASA Astrophysics Data System (ADS)

    Park, Byoung Yoon; Sobolik, Steven R.; Herrick, Courtney G.

    2018-03-01

    A finite element numerical analysis model has been constructed that consists of a mesh that effectively captures the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multimechanism deformation (M-D) salt constitutive model using the daily data of actual wellhead pressure and oil-brine interface location. The salt creep rate is not uniform in the salt dome, and the creep test data for BC salt are limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the salt dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN are used as the field baseline measurement. The structure factor, A 2, and transient strain limit factor, K 0, in the M-D constitutive model are used for the calibration. The value of A 2, obtained experimentally from BC salt, and the value of K 0, obtained from Waste Isolation Pilot Plant salt, are used for the baseline values. To adjust the magnitude of A 2 and K 0, multiplication factors A 2 F and K 0 F are defined, respectively. The A 2 F and K 0 F values of the salt dome and salt drawdown skins surrounding each SPR cavern have been determined through a number of back analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict behaviors of the salt dome, caverns, caprock, and interbed layers. The geotechnical concerns associated with the BC site from this analysis will be explained in a follow-up paper.

  11. Key issues and challenges in developing a pedagogical intervention in the simulation skills center--an action research study.

    PubMed

    Reierson, Inger Åse; Hvidsten, Anne; Wighus, Marianne; Brungot, Solvor; Bjørk, Ida Torunn

    2013-07-01

    Simulation skills centers (SSC) are considered important learning arenas for preparing and qualifying nursing students. Limited clinical placements and claims of diminished learning opportunities raise concerns that newly educated nurses lack proficiency in many psychomotor skills. Accordingly, there is an increased focus on learning in the SSC. However, it has been questioned if the pedagogical underpinning of teaching and learning in the SSC is missing or unclear. At a bachelor nursing education in Norway, there was a desire to change practice and enhance learning in the SSC by systematic use of The Model of Practical Skill Performance (Bjørk and Kirkevold, 2000). A participatory action research design was chosen. A pedagogical intervention was developed and implemented in 2010 in a cohort of eighty-seven first year bachelor nursing students during their basic nursing skill course. The intervention is shortly described. This article reports key issues and challenges that emerged during development of the new intervention. Data to inform the study were collected via thorough meeting minutes and the project leader's logbook, and analyzed using fieldnotes analysis. Six key issues and challenges were identified. These are presented and discussed consecutively in light of their importance for development and implementation of the new intervention. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Key issues of ultraviolet radiation of OH at high altitudes

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

    Zhang, Yuhuai; Wan, Tian; Jiang, Jianzheng

    2014-12-09

    Ultraviolet (UV) emissions radiated by hydroxyl (OH) is one of the fundamental elements in the prediction of radiation signature of high-altitude and high-speed vehicle. In this work, the OH A{sup 2}Σ{sup +}→X{sup 2}Π ultraviolet emission band behind the bow shock is computed under the experimental condition of the second bow-shock ultraviolet flight (BSUV-2). Four related key issues are discussed, namely, the source of hydrogen element in the high-altitude atmosphere, the formation mechanism of OH species, efficient computational algorithm of trace species in rarefied flows, and accurate calculation of OH emission spectra. Firstly, by analyzing the typical atmospheric model, the verticalmore » distributions of the number densities of different species containing hydrogen element are given. According to the different dominating species containing hydrogen element, the atmosphere is divided into three zones, and the formation mechanism of OH species is analyzed in the different zones. The direct simulation Monte Carlo (DSMC) method and the Navier-Stokes equations are employed to compute the number densities of the different OH electronically and vibrationally excited states. Different to the previous work, the trace species separation (TSS) algorithm is applied twice in order to accurately calculate the densities of OH species and its excited states. Using a non-equilibrium radiation model, the OH ultraviolet emission spectra and intensity at different altitudes are computed, and good agreement is obtained with the flight measured data.« less

  13. Key issues of ultraviolet radiation of OH at high altitudes

    NASA Astrophysics Data System (ADS)

    Zhang, Yuhuai; Wan, Tian; Jiang, Jianzheng; Fan, Jing

    2014-12-01

    Ultraviolet (UV) emissions radiated by hydroxyl (OH) is one of the fundamental elements in the prediction of radiation signature of high-altitude and high-speed vehicle. In this work, the OH A2Σ+→ X2Π ultraviolet emission band behind the bow shock is computed under the experimental condition of the second bow-shock ultraviolet flight (BSUV-2). Four related key issues are discussed, namely, the source of hydrogen element in the high-altitude atmosphere, the formation mechanism of OH species, efficient computational algorithm of trace species in rarefied flows, and accurate calculation of OH emission spectra. Firstly, by analyzing the typical atmospheric model, the vertical distributions of the number densities of different species containing hydrogen element are given. According to the different dominating species containing hydrogen element, the atmosphere is divided into three zones, and the formation mechanism of OH species is analyzed in the different zones. The direct simulation Monte Carlo (DSMC) method and the Navier-Stokes equations are employed to compute the number densities of the different OH electronically and vibrationally excited states. Different to the previous work, the trace species separation (TSS) algorithm is applied twice in order to accurately calculate the densities of OH species and its excited states. Using a non-equilibrium radiation model, the OH ultraviolet emission spectra and intensity at different altitudes are computed, and good agreement is obtained with the flight measured data.

  14. Reactive Transport Models with Geomechanics to Mitigate Risks of CO2 Utilization and Storage

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

    Deo, Milind; Huang, Hai; Kweon, Hyukmin

    2016-03-28

    initial high-permeability pathway facilitated the formation of wormholes. The peak cation concentrations and general trends were matched using Toughreact. Batch reactor modeling showed that the geometric factors obtained using powder data that related effective surface area to the BET surface area had to be reduced for fractured samples and cores. This indicates that the available surface area in consolidated samples is lower than that deduced from powder experiments. Field-scale modeling of reactive transport and geomechanics was developed in parallel at Idaho National Laboratory. The model is able to take into account complex chemistry, and consider interactions of natural fractures and faults. Poroelastic geomechanical considerations are also included in the model.« less

  15. Key Durability Issues with Mullite-Based Environmental Barrier Coatings for Si-Based Ceramics

    NASA Technical Reports Server (NTRS)

    Lee, Kang N.

    1999-01-01

    Plasma-sprayed mullite (3Al2O3 central dot 2SiO2) and mullite/yttria-stabilized-zirconia (YSZ) dual layer coatings have been developed to protect silicon-based ceramics from environmental attack. Mullite-based coating systems show excellent durability in air. However, in combustion environments, corrosive species such as molten salt or water vapor penetrate through cracks in the coating and attack the Si-based ceramics along the interface, Thus modification of the coating system for enhanced crack-resistance is necessary for long-term durability in combustion environments. Other key durability issues include interfacial contamination and coating/substrate bonding. Interfacial contamination leads to enhanced oxidation and interfacial pore formation, while weak coating/substrate bonding leads to rapid attack of the interface by corrosive species, both of which can cause premature failure of the coating. Interfacial contamination can be minimized by limiting impurities in coating and substrate materials. The interface may be modified to improve the coating/substrate bond.

  16. Key Durability Issues with Mullite-Based Environmental Barrier Coatings for Si-Based Ceramics

    NASA Technical Reports Server (NTRS)

    Lee, Kang N.

    2000-01-01

    Plasma-sprayed mullite (3Al2O3.2SiO2) and mullite/yttria-stabilized-zirconia (YSZ) dual layer coatings have been developed to protect silicon -based ceramics from environmental attack. Mullite-based coating systems show excellent durability in air. However, in combustion environments, corrosive species such as molten salt or water vapor penetrate through cracks in the coating and attack the Si-based ceramics along the interface. Thus the modification of the coating system for enhanced crack-resistance is necessary for long-term durability in combustion environments. Other key durability issues include interfacial contamination and coating/substrate bonding. Interfacial contamination leads to enhanced oxidation and interfacial pore formation, while a weak coating/substrate bonding leads to rapid attack of the interface by corrosive species, both of which can cause a premature failure of the coating. Interfacial contamination can be minimized by limiting impurities in coating and substrate materials. The interface may be modified to improve the coating/substrate bond.

  17. Epidemiological Data Management during an Outbreak of Ebola Virus Disease: Key Issues and Observations from Sierra Leone.

    PubMed

    Owada, Kei; Eckmanns, Tim; Kamara, Kande-Bure O'Bai; Olu, Olushayo Oluseun

    2016-01-01

    Sierra Leone experienced intense transmission of Ebola virus disease (EVD) from May 2014 to November 2015 during which a total of 8,704 confirmed cases and over 3,589 confirmed deaths were reported. Our field observation showed many issues in the EVD data management system, which may have contributed to the magnitude and long duration of the outbreak. In this perspective article, we explain the key issues with EVD data management in the field, and the resulting obstacles in analyzing key epidemiological indicators during the outbreak response work. Our observation showed that, during the latter part of the EVD outbreak, surveillance and data management improved at all levels in the country as compared to the earlier stage. We identified incomplete filling and late arrival of the case investigation forms at data management centers, difficulties in detecting double entries and merging identified double entries in the database, and lack of clear process of how death of confirmed cases in holding, treatment, and community care centers are reported to the data centers as some of challenges to effective data management. Furthermore, there was no consolidated database that captured and linked all data sources in a structured way. We propose development of a new application tool easily adaptable to new occurrences, regular data harmonization meetings between national and district data management teams, and establishment of a data quality audit system to assure good quality data as ways to improve EVD data management during future outbreaks.

  18. Education Studies: Issues & Critical Perspectives

    ERIC Educational Resources Information Center

    Kassem, Derek; Mufti, Emmanuel; Robinson, John

    2006-01-01

    This major text for Education Studies students provides a critical account of key issues in education today. The text features: (1) A critical analysis of key issues in Education Studies to encourage students' thinking about education in the broadest terms; (2) Themed sections with introductions to link the issues discussed in each chapter; (3)…

  19. Key issues in space nuclear power

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W.

    1991-01-01

    The future appears rich in missions that will extend the frontiers of knowledge, human presence in space, and opportunities for profitable commerce. Key to the success of these ventures is the availability of plentiful, cost effective electric power and assured, low cost access to space. While forecasts of space power needs are problematic, an assessment of future needs based on terrestrial experience has been made. These needs fall into three broad categories: survival, self sufficiency, and industrialization. The cost of delivering payloads to orbital locations from LEO to Mars has been determined and future launch cost reductions projected. From these factors, then, projections of the performance necessary for future solar and nuclear space power options has been made. These goals are largely dependent upon orbital location and energy storage needs. Finally the cost of present space power systems has been determined and projections made for future systems.

  1. An Integrated Geomechanical Investigation, Multi-Parameter Monitoring and Analyses of Babadağ-Gündoğdu Creep-like Landslide

    NASA Astrophysics Data System (ADS)

    Kumsar, Halil; Aydan, Ömer; Tano, Hisataka; Çelik, Sefer Beran; Ulusay, Reşat

    2016-06-01

    A creep-like landslide in the Gündoğdu district of Babadağ town in Denizli (Turkey), where about 2000 people lived within the damaged houses, has been moving with a velocity of 4-14 cm/year since 1940s. Field observations and monitoring together with geomechanical laboratory tests were carried out to investigate the causative factors of the landslide. These studies were conducted as a part of an international research project performed by Turkish and Japanese scientists since 2000. Long-term monitoring stations established involved measurements of meteorological parameters, displacements, acoustic emission counts, variations in groundwater table, borehole strain measurement, in situ permeability and infiltration characteristics of the slope forming materials, and vibrations induced by weaving machines during their operation. Geomechanical properties of the sandstone and marl, which form the unstable slope, were determined from laboratory tests. In addition to the use of conventional 2-D equilibrium method of analyses, a new approach for modelling the long-term creep-like behaviour of the landslide body, based on discrete finite element method, was also proposed and used to analyse the landslide. It was found that the sliding mass has been involving several zones of weakness (interface) between the sandstone and marl layers through in situ monitoring. The monitoring data of pipe strain, groundwater level fluctuation and rainfall, and AE data showed that slope movement accelerated during and after rainy seasons. It was obtained that the proposed numerical method based on discrete finite element method (DFEM), which considers the softening and hardening of stiffness of the weakness zone as a function of rainfall and, is capable of simulating creep-like behaviour of the landslide. Disaster and Emergency Management Authority of Turkey also considered the results of this research and the landslide area was designated as a Natural Disaster Area and the people living in

  2. Geomechanical Model Calibration Using Field Measurements for a Petroleum Reserve

    DOE PAGES

    Park, Byoung Yoon; Sobolik, Steven R.; Herrick, Courtney G.

    2018-01-19

    A finite element numerical analysis model has been constructed that consists of a mesh that effectively captures the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multimechanism deformation (M-D) salt constitutive model using the daily data of actual wellhead pressure and oil–brine interface location. The salt creep rate is not uniform in the salt dome, and the creep test data for BC salt are limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the salt dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN are used as the field baseline measurement.more » The structure factor, A 2, and transient strain limit factor, K o, in the M-D constitutive model are used for the calibration. The value of A 2, obtained experimentally from BC salt, and the value of K o, obtained from Waste Isolation Pilot Plant salt, are used for the baseline values. To adjust the magnitude of A 2 and K0, multiplication factors A 2 F and K o F are defined, respectively. The A 2 F and K0F values of the salt dome and salt drawdown skins surrounding each SPR cavern have been determined through a number of back analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict behaviors of the salt dome, caverns, caprock, and interbed layers. In conclusion, the geotechnical concerns associated with the BC site from this analysis will be explained in a follow-up paper.« less

  3. Geomechanical Model Calibration Using Field Measurements for a Petroleum Reserve

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

    Park, Byoung Yoon; Sobolik, Steven R.; Herrick, Courtney G.

    A finite element numerical analysis model has been constructed that consists of a mesh that effectively captures the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multimechanism deformation (M-D) salt constitutive model using the daily data of actual wellhead pressure and oil–brine interface location. The salt creep rate is not uniform in the salt dome, and the creep test data for BC salt are limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the salt dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN are used as the field baseline measurement.more » The structure factor, A 2, and transient strain limit factor, K o, in the M-D constitutive model are used for the calibration. The value of A 2, obtained experimentally from BC salt, and the value of K o, obtained from Waste Isolation Pilot Plant salt, are used for the baseline values. To adjust the magnitude of A 2 and K0, multiplication factors A 2 F and K o F are defined, respectively. The A 2 F and K0F values of the salt dome and salt drawdown skins surrounding each SPR cavern have been determined through a number of back analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict behaviors of the salt dome, caverns, caprock, and interbed layers. In conclusion, the geotechnical concerns associated with the BC site from this analysis will be explained in a follow-up paper.« less

  4. Key Issues for Navigation and Time Dissemination in NASA's Space Exploration Program

    NASA Technical Reports Server (NTRS)

    Nelson, R. A.; Brodsky, B.; Oria, A. J.; Connolly, J. W.; Sands, O. S.; Welch, B. W.; Ely T.; Orr, R.; Schuchman, L.

    2006-01-01

    The renewed emphasis on robotic and human missions within NASA's space exploration program warrants a detailed consideration of how the positions of objects in space will be determined and tracked, whether they be spacecraft, human explorers, robots, surface vehicles, or science instrumentation. The Navigation Team within the NASA Space Communications Architecture Working Group (SCAWG) has addressed several key technical issues in this area and the principle findings are reported here. For navigation in the vicinity of the Moon, a variety of satellite constellations have been investigated that provide global or regional surface position determination and timely services analogous to those offered by GPS at Earth. In the vicinity of Mars, there are options for satellite constellations not available at the Moon due to the gravitational perturbations from Earth, such as two satellites in an aerostationary orbit. Alternate methods of radiometric navigation as considered, including one- and two-way signals, as well as autonomous navigation. The use of a software radio capable of receiving all available signal sources, such as GPS, pseudolites, and communication channels, is discussed. Methods of time transfer and dissemination are also considered in this paper.

  5. Key issues in transplant tourism.

    PubMed

    Akoh, Jacob A

    2012-02-24

    Access to organ transplantation depends on national circumstances, and is partly determined by the cost of health care, availability of transplant services, the level of technical capacity and the availability of organs. Commercial transplantation is estimated to account for 5%-10% (3500-7000) of kidney transplants performed annually throughout the world. This review is to determine the state and outcome of renal transplantation associated with transplant tourism (TT) and the key challenges with such transplantation. The stakeholders of commercial transplantation include: patients on the waiting lists in developed countries or not on any list in developing countries; dialysis funding bodies; middlemen, hosting transplant centres; organ-exporting countries; and organ vendors. TT and commercial kidney transplants are associated with a high incidence of surgical complications, acute rejection and invasive infection which cause major morbidity and mortality. There are ethical and medical concerns regarding the management of recipients of organs from vendors. The growing demand for transplantation, the perceived failure of altruistic donation in providing enough organs has led to calls for a legalised market in organ procurement or regulated trial in incentives for donation. Developing transplant services worldwide has many benefits - improving results of transplantation as they would be performed legally, increasing the donor pool and making TT unnecessary. Meanwhile there is a need to re-examine intrinsic attitudes to TT bearing in mind the cultural and economic realities of globalisation. Perhaps the World Health Organization in conjunction with The Transplantation Society would set up a working party of stakeholders to study this matter in greater detail and make recommendations.

  6. Key issues in transplant tourism

    PubMed Central

    Akoh, Jacob A

    2012-01-01

    Access to organ transplantation depends on national circumstances, and is partly determined by the cost of health care, availability of transplant services, the level of technical capacity and the availability of organs. Commercial transplantation is estimated to account for 5%-10% (3500-7000) of kidney transplants performed annually throughout the world. This review is to determine the state and outcome of renal transplantation associated with transplant tourism (TT) and the key challenges with such transplantation. The stakeholders of commercial transplantation include: patients on the waiting lists in developed countries or not on any list in developing countries; dialysis funding bodies; middlemen, hosting transplant centres; organ-exporting countries; and organ vendors. TT and commercial kidney transplants are associated with a high incidence of surgical complications, acute rejection and invasive infection which cause major morbidity and mortality. There are ethical and medical concerns regarding the management of recipients of organs from vendors. The growing demand for transplantation, the perceived failure of altruistic donation in providing enough organs has led to calls for a legalised market in organ procurement or regulated trial in incentives for donation. Developing transplant services worldwide has many benefits - improving results of transplantation as they would be performed legally, increasing the donor pool and making TT unnecessary. Meanwhile there is a need to re-examine intrinsic attitudes to TT bearing in mind the cultural and economic realities of globalisation. Perhaps the World Health Organization in conjunction with The Transplantation Society would set up a working party of stakeholders to study this matter in greater detail and make recommendations. PMID:24175191

  7. Development Co-operation and Linkages in Higher Education: Key Issues Concerning Policy and Organisation

    NASA Astrophysics Data System (ADS)

    van Audenhove, Leo

    1998-09-01

    The term linkage is used to indicate co-operation between an institution in the North and an institution in the South. Donor organisations have generally used linkages to support the development of higher education and research in developing countries. Over time, there has been a trend away from co-operation on individual academic projects towards broader development co- operation and concentration on selected institutions. This shift raises questions about organisation, procedures and support mechanisms, and about the mandate and capabilities of universities in the North, given the frequently asymmetrical relationship between Northern institutions with their own research agendas and Southern beneficiaries. The recent restructuring of Canadian, Dutch, Norwegian and Swedish support for higher education and research is the result of a search for new, more appropriate models of co-operation. This paper examines the evolution of key issues of policy and organisation within the international donor community.

  8. Key issues for low-cost FGD installations

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

    DePriest, W.; Mazurek, J.M.

    1995-12-01

    This paper will discuss various methods for installing low-cost FGD systems. The paper will include a discussion of various types of FGD systems available, both wet and dry, and will compare the relative cost of each type. Important design issues, such as use of spare equipment, materials of construction, etc. will be presented. An overview of various low-cost construction techniques (i.e., modularization) will be included. This paper will draw heavily from Sargent & Lundy`s database of past and current FGD projects together with information we gathered for several Electric Power Research Institute (EPRI) studies on the subject.

  9. Key Issues in the Modes of Action and Effects of Trichloroethylene Metabolites for Liver and Kidney Tumorigenesis

    PubMed Central

    Caldwell, Jane C.; Keshava, Nagalakshmi

    2006-01-01

    Trichloroethylene (TCE) exposure has been associated with increased risk of liver and kidney cancer in both laboratory animal and epidemiologic studies. The U.S. Environmental Protection Agency 2001 draft TCE risk assessment concluded that it is difficult to determine which TCE metabolites may be responsible for these effects, the key events involved in their modes of action (MOAs), and the relevance of these MOAs to humans. In this article, which is part of a mini-monograph on key issues in the health risk assessment of TCE, we present a review of recently published scientific literature examining the effects of TCE metabolites in the context of the preceding questions. Studies of the TCE metabolites dichloroacetic acid (DCA), trichloroacetic acid (TCA), and chloral hydrate suggest that both DCA and TCA are involved in TCE-induced liver tumorigenesis and that many DCA effects are consistent with conditions that increase the risk of liver cancer in humans. Studies of S-(1,2-dichlorovinyl)-l-cysteine have revealed a number of different possible cell signaling effects that may be related to kidney tumorigenesis at lower concentrations than those leading to cytotoxicity. Recent studies of trichloroethanol exploring an alternative hypothesis for kidney tumorigenesis have failed to establish the formation of formate as a key event for TCE-induced kidney tumors. Overall, although MOAs and key events for TCE-induced liver and kidney tumors have yet to be definitively established, these results support the likelihood that toxicity is due to multiple metabolites through several MOAs, none of which appear to be irrelevant to humans. PMID:16966105

  10. Challenges, uncertainties, and issues facing gas production from gas-hydrate deposits

    USGS Publications Warehouse

    Moridis, G.J.; Collett, T.S.; Pooladi-Darvish, M.; Hancock, S.; Santamarina, C.; Boswel, R.; Kneafsey, T.; Rutqvist, J.; Kowalsky, M.B.; Reagan, M.T.; Sloan, E.D.; Sum, A.K.; Koh, C.A.

    2011-01-01

    The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas-hydrate (GH) petroleum system; to discuss advances, requirements, and suggested practices in GH prospecting and GH deposit characterization; and to review the associated technical, economic, and environmental challenges and uncertainties, which include the following: accurate assessment of producible fractions of the GH resource; development of methods for identifying suitable production targets; sampling of hydrate-bearing sediments (HBS) and sample analysis; analysis and interpretation of geophysical surveys of GH reservoirs; well-testing methods; interpretation of well-testing results; geomechanical and reservoir/well stability concerns; well design, operation, and installation; field operations and extending production beyond sand-dominated GH reservoirs; monitoring production and geomechanical stability; laboratory investigations; fundamental knowledge of hydrate behavior; the economics of commercial gas production from hydrates; and associated environmental concerns. ?? 2011 Society of Petroleum Engineers.

  11. Neuropathological biomarker candidates in brain tumors: key issues for translational efficiency.

    PubMed

    Hainfellner, J A; Heinzl, H

    2010-01-01

    Brain tumors comprise a large spectrum of rare malignancies in children and adults that are often associated with severe neurological symptoms and fatal outcome. Neuropathological tumor typing provides both prognostic and predictive tissue information which is the basis for optimal postoperative patient management and therapy. Molecular biomarkers may extend and refine prognostic and predictive information in a brain tumor case, providing more individualized and optimized treatment options. In the recent past a few neuropathological brain tumor biomarkers have translated smoothly into clinical use whereas many candidates show protracted translation. We investigated the causes of protracted translation of candidate brain tumor biomarkers. Considering the research environment from personal, social and systemic perspectives we identified eight determinants of translational success: methodology, funding, statistics, organization, phases of research, cooperation, self-reflection, and scientific progeny. Smoothly translating biomarkers are associated with low degrees of translational complexity whereas biomarkers with protracted translation are associated with high degrees. Key issues for translational efficiency of neuropathological brain tumor biomarker research seem to be related to (i) the strict orientation to the mission of medical research, that is the improval of medical practice as primordial purpose of research, (ii) definition of research priorities according to clinical needs, and (iii) absorption of translational complexities by means of operatively beneficial standards. To this end, concrete actions should comprise adequate scientific education of young investigators, and shaping of integrative diagnostics and therapy research both on the local level and the level of influential international brain tumor research platforms.

  12. The Earth's radiation belts modelling : main issues and key directions for improvement

    NASA Astrophysics Data System (ADS)

    Maget, Vincent; Boscher, Daniel

    The Earth's radiation belts can be considered as an opened system covering a wide part of the inner magnetosphere which closely interacts with the surrounding cold plasma. Although its population constitutes only the highly energetic tail of the global inner magnetosphere plasma (electrons from a few tens of keV to more than 5 MeV and protons up to 500MeV), their modelling is of prime importance for satellite robustness design. They have been modelled at ONERA for more than 15 years now through the Salammbˆ code, which models the dynamic of the Earth's radiation belts at the drift timescale (order of the hour). It takes into accounts the main processes acting on the trapped particles, which depends on the electromagnetic configuration and on the characteristics of the surrounding cold plasma : the ionosphere as losses terms, the plasmasheet as sources ones and the plasmasphere through interactions (waves-particles interactions, coulomb scattering, electric fields shielding, . . . ). Consequently, a fine knowledge of these environments and their interactions with the radiation belts is of prime importance in their modelling. Issues in the modelling currently exist, but key directions for improvements can also be highlighted. This talk aims at presenting both of them according to recent developments performed at ONERA besides the Salammbˆ code. o

  13. A review on the key issues for lithium-ion battery management in electric vehicles

    NASA Astrophysics Data System (ADS)

    Lu, Languang; Han, Xuebing; Li, Jianqiu; Hua, Jianfeng; Ouyang, Minggao

    2013-03-01

    Compared with other commonly used batteries, lithium-ion batteries are featured by high energy density, high power density, long service life and environmental friendliness and thus have found wide application in the area of consumer electronics. However, lithium-ion batteries for vehicles have high capacity and large serial-parallel numbers, which, coupled with such problems as safety, durability, uniformity and cost, imposes limitations on the wide application of lithium-ion batteries in the vehicle. The narrow area in which lithium-ion batteries operate with safety and reliability necessitates the effective control and management of battery management system. This present paper, through the analysis of literature and in combination with our practical experience, gives a brief introduction to the composition of the battery management system (BMS) and its key issues such as battery cell voltage measurement, battery states estimation, battery uniformity and equalization, battery fault diagnosis and so on, in the hope of providing some inspirations to the design and research of the battery management system.

  14. A view of software management issues

    NASA Technical Reports Server (NTRS)

    Manley, J. H.

    1985-01-01

    The Software Development Environment (SDE) Panel addressed key programmatic, scope, and structural issues raised by its members and the general audience regarding the proposed software development environment for the Space Station program. The general team approach taken by this group led to a consensus on 18 recommendations to NASA mangament regarding the acquisition and definition of the SDE. This approach was keyed by the initial issues presentation given to the general audience. Additional issues (for a total of 23) were developed by the panelists in their first closed session from which key areas were selected and discussed in open session. These discussions led to key recommendations which are summarized and described.

  15. Revisiting Employee Assistance Programs and Substance Use Problems in the Workplace: Key Issues and a Research Agenda

    PubMed Central

    Levy Merrick, Elizabeth S.; Volpe-Vartanian, Joanna; Horgan, Constance M.; McCann, Bernard

    2012-01-01

    This column describes employee assistance program (EAPs) and identifies key issues for contemporary EAPs. These programs began as occupational alcohol programs and have evolved into more comprehensive resources. To better understand contemporary EAPs, the authors suggest a research agenda at includes descriptive studies to provide an up-to-date picture of services; investigations of how contemporary EAPs address substance use problems, including management consultation for early identification; further study of EAPs’ effects on outcomes, such as productivity and work group outcomes; examination of the relationship between EAPs and other workplace resources; further examination of influences on EAP utilization; and development and testing of EAP performance measures. PMID:17914000

  16. Health care financing in Asia: key issues and challenges.

    PubMed

    Kwon, Soonman

    2011-09-01

    This article examines the major elements of health care financing such as financial risk protection, resource generation, resource pooling, and purchasing and payment; provides key lessons; and discusses the challenges for health care financing systems of Asian countries. With the exception of Japan, Korea, Taiwan, and Thailand, most health care systems of Asia provide very limited financial risk protection. The role of public prepaid schemes such as tax and social health insurance is minimal, and out-of-pocket payment is a major source of financing. The large informal sector is a major challenge to the extension of population coverage in many low-income countries of Asia, which must seek the optimal mix of tax subsidy and health insurance for universal coverage. Implementation of effective payment systems to control the behavior of health care providers is also a key factor in the success of health care financing reform in Asia.

  17. Key issues for determining the exploitable water resources in a Mediterranean river basin.

    PubMed

    Pedro-Monzonís, María; Ferrer, Javier; Solera, Abel; Estrela, Teodoro; Paredes-Arquiola, Javier

    2015-01-15

    One of the major difficulties in water planning is to determine the water availability in a water resource system in order to distribute water sustainably. In this paper, we analyze the key issues for determining the exploitable water resources as an indicator of water availability in a Mediterranean river basin. Historically, these territories are characterized by heavily regulated water resources and the extensive use of unconventional resources (desalination and wastewater reuse); hence, emulating the hydrological cycle is not enough. This analysis considers the Jucar River Basin as a case study. We have analyzed the different possible combinations between the streamflow time series, the length of the simulation period and the reliability criteria. As expected, the results show a wide dispersion, proving the great influence of the reliability criteria used for the quantification and localization of the exploitable water resources in the system. Therefore, it is considered risky to provide a single value to represent the water availability in the Jucar water resource system. In this sense, it is necessary that policymakers and stakeholders make a decision about the methodology used to determine the exploitable water resources in a river basin. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Effects of fault-controlled CO2 alteration on mineralogical and geomechanical properties of reservoir and seal rocks, Crystal Geyser, Green River, Utah

    NASA Astrophysics Data System (ADS)

    Major, J. R.; Eichhubl, P.; Urquhart, A.; Dewers, T. A.

    2012-12-01

    An understanding of the coupled chemical and mechanical properties of reservoir and seal units undergoing CO2 injection is critical for modeling reservoir behavior in response to the introduction of CO2. The implementation of CO2 sequestration as a mitigation strategy for climate change requires extensive risk assessment that relies heavily on computer models of subsurface reservoirs. Numerical models are fundamentally limited by the quality and validity of their input parameters. Existing models generally lack constraints on diagenesis, failing to account for the coupled geochemical or geomechanical processes that affect reservoir and seal unit properties during and after CO2 injection. For example, carbonate dissolution or precipitation after injection of CO2 into subsurface brines may significantly alter the geomechanical properties of reservoir and seal units and thus lead to solution-enhancement or self-sealing of fractures. Acidified brines may erode and breach sealing units. In addition, subcritical fracture growth enhanced by the presence of CO2 could ultimately compromise the integrity of sealing units, or enhance permeability and porosity of the reservoir itself. Such unknown responses to the introduction of CO2 can be addressed by laboratory and field-based observations and measurements. Studies of natural analogs like Crystal Geyser, Utah are thus a critical part of CO2 sequestration research. The Little Grand Wash and Salt Wash fault systems near Green River, Utah, host many fossil and active CO2 seeps, including Crystal Geyser, serving as a faulted anticline CO2 reservoir analog. The site has been extensively studied for sequestration and reservoir applications, but less attention has been paid to the diagenetic and geomechanical aspects of the fault zone. XRD analysis of reservoir and sealing rocks collected along transects across the Little Grand Wash Fault reveal mineralogical trends in the Summerville Fm (a siltstone seal unit) with calcite and

  19. Prospects and applications near ferroelectric quantum phase transitions: a key issues review.

    PubMed

    Chandra, P; Lonzarich, G G; Rowley, S E; Scott, J F

    2017-11-01

    The emergence of complex and fascinating states of quantum matter in the neighborhood of zero temperature phase transitions suggests that such quantum phenomena should be studied in a variety of settings. Advanced technologies of the future may be fabricated from materials where the cooperative behavior of charge, spin and current can be manipulated at cryogenic temperatures. The progagating lattice dynamics of displacive ferroelectrics make them appealing for the study of quantum critical phenomena that is characterized by both space- and time-dependent quantities. In this key issues article we aim to provide a self-contained overview of ferroelectrics near quantum phase transitions. Unlike most magnetic cases, the ferroelectric quantum critical point can be tuned experimentally to reside at, above or below its upper critical dimension; this feature allows for detailed interplay between experiment and theory using both scaling and self-consistent field models. Empirically the sensitivity of the ferroelectric T c 's to external and to chemical pressure gives practical access to a broad range of temperature behavior over several hundreds of Kelvin. Additional degrees of freedom like charge and spin can be added and characterized systematically. Satellite memories, electrocaloric cooling and low-loss phased-array radar are among possible applications of low-temperature ferroelectrics. We end with open questions for future research that include textured polarization states and unusual forms of superconductivity that remain to be understood theoretically.

  20. Prospects and applications near ferroelectric quantum phase transitions: a key issues review

    NASA Astrophysics Data System (ADS)

    Chandra, P.; Lonzarich, G. G.; Rowley, S. E.; Scott, J. F.

    2017-11-01

    The emergence of complex and fascinating states of quantum matter in the neighborhood of zero temperature phase transitions suggests that such quantum phenomena should be studied in a variety of settings. Advanced technologies of the future may be fabricated from materials where the cooperative behavior of charge, spin and current can be manipulated at cryogenic temperatures. The progagating lattice dynamics of displacive ferroelectrics make them appealing for the study of quantum critical phenomena that is characterized by both space- and time-dependent quantities. In this key issues article we aim to provide a self-contained overview of ferroelectrics near quantum phase transitions. Unlike most magnetic cases, the ferroelectric quantum critical point can be tuned experimentally to reside at, above or below its upper critical dimension; this feature allows for detailed interplay between experiment and theory using both scaling and self-consistent field models. Empirically the sensitivity of the ferroelectric T c’s to external and to chemical pressure gives practical access to a broad range of temperature behavior over several hundreds of Kelvin. Additional degrees of freedom like charge and spin can be added and characterized systematically. Satellite memories, electrocaloric cooling and low-loss phased-array radar are among possible applications of low-temperature ferroelectrics. We end with open questions for future research that include textured polarization states and unusual forms of superconductivity that remain to be understood theoretically.

  1. The Future We Want: Key Issues on Sustainable Development in Higher Education after Rio and the UN Decade of Education for Sustainable Development

    ERIC Educational Resources Information Center

    Leal Filho, Walter; Manolas, Evangelos; Pace, Paul

    2015-01-01

    Purpose: This paper aims to provide a description of the achievements of the United Nations (UN) Decade of Education for Sustainable Development (2005-2014) with a focus on higher education, and it describes some of the key issues which will guide sustainable development in the coming years. Design/methodology/approach: The paper initially…

  2. The Work/Family Challenge: A Key Career Development Issue.

    ERIC Educational Resources Information Center

    Kahnweiler, William M; Kahnweiler, Jennifer B.

    1992-01-01

    A few corporations are responding to the impact of family structural changes on workers' ability to balance their roles with flexible benefits and schedules and with training. Work/family issues are an integral part of career and life decision making and must be incorporated into the career development process. (SK)

  3. Key issues in life cycle assessment of ethanol production from lignocellulosic biomass: Challenges and perspectives.

    PubMed

    Singh, Anoop; Pant, Deepak; Korres, Nicholas E; Nizami, Abdul-Sattar; Prasad, Shiv; Murphy, Jerry D

    2010-07-01

    Progressive depletion of conventional fossil fuels with increasing energy consumption and greenhouse gas (GHG) emissions have led to a move towards renewable and sustainable energy sources. Lignocellulosic biomass is available in massive quantities and provides enormous potential for bioethanol production. However, to ascertain optimal biofuel strategies, it is necessary to take into account environmental impacts from cradle to grave. Life cycle assessment (LCA) techniques allow detailed analysis of material and energy fluxes on regional and global scales. This includes indirect inputs to the production process and associated wastes and emissions, and the downstream fate of products in the future. At the same time if not used properly, LCA can lead to incorrect and inappropriate actions on the part of industry and/or policy makers. This paper aims to list key issues for quantifying the use of resources and releases to the environment associated with the entire life cycle of lignocellulosic bioethanol production. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. A geomechanical model of a sinkhole formation

    NASA Astrophysics Data System (ADS)

    Danchiv, Alexandru; Zamfirescu, Florian; Mocuta, Marius; Popa, Iulian; Zlibut, Alexandru; Huggenberger, Peter; Zechner, Eric; Dresmann, Horst; Scheidler, Stefan; Wiesmeier, Stefan

    2016-04-01

    On December 2010 a sinkhole was suddenly formed close to the eastern flank of Ocna-Mures salt dome. Soon after the collapse the sinkhole was filled with brine forming a salt lake called Plus Lake. The total volume of sinkhole of about 100000 m3 remained constant since February 2011. The Ocna Mures salt dome is situated on the western border of the Transylvanian basin (Romania) and has been exploited for a long time. The ceilings of some shallow mine chambers are now collapsed and filled with brine. Along the eastern flank of the salt dome there is a disturbed zone due to diapirism. Its presence is suggested by the strong fragmentation of rock in the boreholes drilled along the salt-sterile contact, as it resulted from the low values of RQD index. The sinkhole is probably due to a pressure increase along the diapir flank. The causes of this sudden increase of pressure are not well known. Most probably it is due to the damage of the tubing of a flank borehole as mentioned in a technical report of the exploiting company. The injected fresh water expelled through the breaches of the damaged borehole and, due to the high pressure flushed up the crushed material of the disturbed zone. In order to better understand the setting up of the Plus Lake joint research efforts were performed by teams from Bucharest and Basel Universities since 2013. For the geomechanical approach a numerical model was performed using the Flac 7.0 code. In a first stage the creep behavior of salt was analyzed considering a Norton creep law. It resulted that after 100 years the salt reached equilibrium, the creep could be neglected and in a first approximation mechanical equilibrium could be analyzed considering only an elasto-plastic behavior of both the salt and the sterile. For both the salt and the surrounding sedimentary rocks the Mohr-Coulomb criterion was considered. The properties of sterile rocks were estimated following the GSI system. Due to poor rock quality the strength parameters have

  5. Risk management of key issues of FPSO

    NASA Astrophysics Data System (ADS)

    Sun, Liping; Sun, Hai

    2012-12-01

    Risk analysis of key systems have become a growing topic late of because of the development of offshore structures. Equipment failures of offloading system and fire accidents were analyzed based on the floating production, storage and offloading (FPSO) features. Fault tree analysis (FTA), and failure modes and effects analysis (FMEA) methods were examined based on information already researched on modules of relex reliability studio (RRS). Equipment failures were also analyzed qualitatively by establishing a fault tree and Boolean structure function based on the shortage of failure cases, statistical data, and risk control measures examined. Failure modes of fire accident were classified according to the different areas of fire occurrences during the FMEA process, using risk priority number (RPN) methods to evaluate their severity rank. The qualitative analysis of FTA gave the basic insight of forming the failure modes of FPSO offloading, and the fire FMEA gave the priorities and suggested processes. The research has practical importance for the security analysis problems of FPSO.

  6. Sexual Health Services for Young People in a Rural Area of Northern Ireland: A Study of the Key Issues for Those Who Provide Them

    ERIC Educational Resources Information Center

    McCann, Lyndsey; Donnelly, Lyn; Quinn, Phelim; McAnerney, Rosemary

    2008-01-01

    Objective: To identify the key issues for service providers in delivering high quality sexual health services, responsive to the needs of young people, in a rural area of Northern Ireland. Design: A triangulation survey approach using questionnaires, in-depth interviews and focus groups was undertaken with a range of organizations and…

  7. Key issues in the prevention of obesity.

    PubMed

    Gill, T P

    1997-01-01

    Obesity is a serious, chronic medical condition which is associated with a wide range of debilitating and life-threatening conditions. It imposes huge financial burdens on health care systems and the community at large. Obesity develops over time and once it has done so, is difficult to treat. Therefore, the prevention of weight gain offers the only truly effective means of controlling obesity. Very little research has directly addressed the issue of obesity prevention and previous efforts to prevent obesity amongst individuals, groups or whole communities have had very limited success. However, we have learned sufficient from past preventive activities to realise that the management of obesity will require a comprehensive range of strategies with actions that target those with existing weight problems, those at high risk of developing obesity as well as the community as a whole. The prevention and management of obesity in children should be considered a priority as there is a high risk of persistence into adulthood.

  8. Key Scientific Issues in the Health Risk Assessment of Trichloroethylene

    PubMed Central

    Chiu, Weihsueh A.; Caldwell, Jane C.; Keshava, Nagalakshmi; Scott, Cheryl Siegel

    2006-01-01

    Trichloroethylene (TCE) is a common environmental contaminant at hazardous waste sites and in ambient and indoor air. Assessing the human health risks of TCE is challenging because of its inherently complex metabolism and toxicity and the widely varying perspectives on a number of critical scientific issues. Because of this complexity, the U.S. Environmental Protection Agency (EPA) drew upon scientific input and expertise from a wide range of groups and individuals in developing its 2001 draft health risk assessment of TCE. This scientific outreach, which was aimed at engaging a diversity of perspectives rather than developing consensus, culminated in 2000 with 16 state-of-the-science articles published together as an Environmental Health Perspectives supplement. Since that time, a substantial amount of new scientific research has been published that is relevant to assessing TCE health risks. Moreover, a number of difficult or controversial scientific issues remain unresolved and are the subject of a scientific consultation with the National Academy of Sciences coordinated by the White House Office of Science and Technology Policy and co-sponsored by a number of federal agencies, including the U.S. EPA. The articles included in this mini-monograph provide a scientific update on the most prominent of these issues: the pharmacokinetics of TCE and its metabolites, mode(s) of action and effects of TCE metabolites, the role of peroxisome proliferator–activated receptor in TCE toxicity, and TCE cancer epidemiology. PMID:16966103

  9. Key statistical and analytical issues for evaluating treatment effects in periodontal research.

    PubMed

    Tu, Yu-Kang; Gilthorpe, Mark S

    2012-06-01

    Statistics is an indispensible tool for evaluating treatment effects in clinical research. Due to the complexities of periodontal disease progression and data collection, statistical analyses for periodontal research have been a great challenge for both clinicians and statisticians. The aim of this article is to provide an overview of several basic, but important, statistical issues related to the evaluation of treatment effects and to clarify some common statistical misconceptions. Some of these issues are general, concerning many disciplines, and some are unique to periodontal research. We first discuss several statistical concepts that have sometimes been overlooked or misunderstood by periodontal researchers. For instance, decisions about whether to use the t-test or analysis of covariance, or whether to use parametric tests such as the t-test or its non-parametric counterpart, the Mann-Whitney U-test, have perplexed many periodontal researchers. We also describe more advanced methodological issues that have sometimes been overlooked by researchers. For instance, the phenomenon of regression to the mean is a fundamental issue to be considered when evaluating treatment effects, and collinearity amongst covariates is a conundrum that must be resolved when explaining and predicting treatment effects. Quick and easy solutions to these methodological and analytical issues are not always available in the literature, and careful statistical thinking is paramount when conducting useful and meaningful research. © 2012 John Wiley & Sons A/S.

  10. Public Key Infrastructure Study

    DTIC Science & Technology

    1994-04-01

    commerce. This Public Key Infrastructure (PKI) study focuses on the United States Federal Government operations, but also addresses national and global ... issues in order to facilitate the interoperation of protected electronic commerce among the various levels of government in the U.S., private citizens

  11. Geological, geomechanical and geostatistical assessment of rockfall hazard in San Quirico Village (Abruzzo, Italy)

    NASA Astrophysics Data System (ADS)

    Chiessi, Vittorio; D'Orefice, Maurizio; Scarascia Mugnozza, Gabriele; Vitale, Valerio; Cannese, Christian

    2010-07-01

    This paper describes the results of a rockfall hazard assessment for the village of San Quirico (Abruzzo region, Italy) based on an engineering-geological model. After the collection of geological, geomechanical, and geomorphological data, the rockfall hazard assessment was performed based on two separate approaches: i) simulation of detachment of rock blocks and their downhill movement using a GIS; and ii) application of geostatistical techniques to the analysis of georeferenced observations of previously fallen blocks, in order to assess the probability of arrival of blocks due to potential future collapses. The results show that the trajectographic analysis is significantly influenced by the input parameters, with particular reference to the coefficients of restitution values. In order to solve this problem, the model was calibrated based on repeated field observations. The geostatistical approach is useful because it gives the best estimation of point-source phenomena such as rockfalls; however, the sensitivity of results to basic assumptions, e.g. assessment of variograms and choice of a threshold value, may be problematic. Consequently, interpolations derived from different variograms have been used and compared among them; hence, those showing the lowest errors were adopted. The data sets which were statistically analysed are relevant to both kinetic energy and surveyed rock blocks in the accumulation area. The obtained maps highlight areas susceptible to rock block arrivals, and show that the area accommodating the new settlement of S. Quirico Village has the highest level of hazard according to both probabilistic and deterministic methods.

  12. Austrian Guideline for Geomechanical Design of Tunnels - Necessity for Cooperation between Geologists, Geotechnical and Civil Engineers

    NASA Astrophysics Data System (ADS)

    Schwarz, Ludwig; Eder, Stefan; Mattle, Bruno; Hammer, Helmut

    Rising competitive pressure in the construction business, ever tighter schedules being set up by the clients and ongoing disputes between engineering geologists and civil engineers about the role of geotechnical engineers have - in the last few years - led to increasing discussions between engineers and geologists about the allocation of competences during the design process of underground structures. In the course of this debate, which is often polemic and anything but objective, important information is quite frequently lost - a development which may not only be to the disadvantage of the client but which may also do damage to the reputation of the professions involved. The design procedure of the new Austrian guideline for the geomechanical design of underground structures requires a close collaboration of geologists, geotechnical and civil engineers, yet without allocating competences. While preparing the tender documents for the first construction lot of the Northern feeder line of the Brenner base tunnel, the necessity of a close cooperation of the involved professions became apparent due to the complex geological situation encountered in the project area and the enormous amount of data available. Despite these difficult boundary conditions, the successful application of the guideline was last but not least the result of the joint efforts of the multidisciplinary design team.

  13. Implications of Key Performance Indicator Issues in Ontario Universities Explored

    ERIC Educational Resources Information Center

    Chan, Vivian

    2015-01-01

    Since 1998, the Ministry of Training, Colleges and Universities in Ontario, Canada, has required that data on specific key performance indicators (KPIs) be made public by its publicly funded universities. The information is intended to be used by universities to demonstrate their achievements, to improve their programmes and services, and to…

  14. Building geomechanical characteristic model in Ilan geothermal area, NE Taiwan

    NASA Astrophysics Data System (ADS)

    Chiang, Yu-Hsuan; Hung, Jih-Hao

    2015-04-01

    National Energy Program-Phase II (NEPPII) was initiated to understand the geomechanical characteristic in Ilan geothermal area. In this study, we integrate well cores and logs (e.g. Nature Gamma-ray, Normal resistivity, Formation Micro Imager) which were acquired in HongChaiLin (HCL), Duck-Field (DF) and IC21 to determine the depth of fracture zone, in-situ stress state, the depth of basement and lithological characters. In addition, the subsurface in-situ stress state will be helpful to analyze the fault reactivation potential and slip tendency. By retrieved core from HCL well and the results of geophysical logging, indicated that the lithological character is slate (520m ~ 1500m) and the basement depth is around 520m. To get the minimum and maximum horizontal stress, several hydraulic fracturing tests were conducted in the interval of 750~765m on HCL well. The horizontal maximum and minimum stresses including the hydrostatic pressure are calculated as 15.39MPa and 13.57MPa, respectively. The vertical stress is decided by measuring the core density from 738m to 902m depth. The average core density is 2.71 g/cm3, and the vertical stress is 19.95 MPa (at 750m). From DF well, the basement depth is 468.9m. Besides, by analyzing the IC21 well logging data, we know the in-situ orientation of maximum horizontal stress is NE-SW. Using these parameters, the fault reactivation potential and slip tendency can be analyzed with 3DStress, Traptester software and demonstrated on model. On the other hand, we interpreted the horizons and faults from the nine seismic profiles including six N-S profiles, two W-E profiles and one NE-SW profile to construct the 3D subsurface structure model with GOCAD software. The result shows that Zhuosui fault and Kankou Formation are dip to north, but Hanxi fault and Xiaonanao fault are dip to south. In addition, there is a syncline-like structure on Nansuao Formation and the Chingshuihu member of the Lushan Formation. However, there is a conflict

  15. Hydro-bio-geomechanical properties of hydrate-bearing sediments from Nankai Trough

    USGS Publications Warehouse

    Santamarina, J.C.; Dai, Shifeng; Terzariol, M.; Jang, Jeonghwan; Waite, William F.; Winters, William J.; Nagao, J.; Yoneda, J.; Konno, Y.; Fujii, T.; Suzuki, K.

    2015-01-01

    Natural hydrate-bearing sediments from the Nankai Trough, offshore Japan, were studied using the Pressure Core Characterization Tools (PCCTs) to obtain geomechanical, hydrological, electrical, and biological properties under in situ pressure, temperature, and restored effective stress conditions. Measurement results, combined with index-property data and analytical physics-based models, provide unique insight into hydrate-bearing sediments in situ. Tested cores contain some silty-sands, but are predominantly sandy- and clayey-silts. Hydrate saturations Sh range from 0.15 to 0.74, with significant concentrations in the silty-sands. Wave velocity and flexible-wall permeameter measurements on never-depressurized pressure-core sediments suggest hydrates in the coarser-grained zones, the silty-sands where Sh exceeds 0.4, contribute to soil-skeletal stability and are load-bearing. In the sandy- and clayey-silts, where Sh < 0.4, the state of effective stress and stress history are significant factors determining sediment stiffness. Controlled depressurization tests show that hydrate dissociation occurs too quickly to maintain thermodynamic equilibrium, and pressure–temperature conditions track the hydrate stability boundary in pure-water, rather than that in seawater, in spite of both the in situ pore water and the water used to maintain specimen pore pressure prior to dissociation being saline. Hydrate dissociation accompanied with fines migration caused up to 2.4% vertical strain contraction. The first-ever direct shear measurements on never-depressurized pressure-core specimens show hydrate-bearing sediments have higher sediment strength and peak friction angle than post-dissociation sediments, but the residual friction angle remains the same in both cases. Permeability measurements made before and after hydrate dissociation demonstrate that water permeability increases after dissociation, but the gain is limited by the transition from hydrate saturation

  16. Current Issues: Critical Issues Confronting the Nation and the World. 1997 Edition [and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Close Up Foundation, Arlington, VA.

    This student text and teacher's guide feature current events and policy issues that are in discussion today. The books offer background on 20 important domestic and foreign policy issues and present arguments from both sides of key issues. The books are divided into three sections. Section 1, "The Federal Government," contains: (1) "The Clinton…

  17. Key issues to consider when using alum sludge as substrate in constructed wetland.

    PubMed

    Zhao, Xiaohong; Zhao, Yaqian; Wang, Wenke; Yang, Yongzhe; Babatunde, Akintunde; Hu, Yuansheng; Kumar, Lordwin

    2015-01-01

    Globally, alum sludge is an easily, locally and largely available by-product from water treatment plants where aluminium sulphate is used as the coagulant for raw water purification. Owing to the high content of Al ions (29.7±13.3% dry weight) in alum sludge and the strong affinity of Al ions to adsorb various pollutants especially phosphorus (P), alum sludge (in the form of dewatered cakes) has been investigated in recent years as a low-cost alternative substrate in constructed wetland (CW) systems to enhance the treatment efficiency especially for high strength P-containing wastewater. Long-term trials in different scales have demonstrated that the alum sludge-based CW is a promising technique with a two-pronged feature of using 'waste' for wastewater treatment. Alum sludge cakes in CW can serve as a medium for wetland plant growth, as a carrier for biofilm development and as a porous material for wastewater infiltration. After the intensive studies of the alum sludge-based CW system, this paper aims to address the key issues and concerns pertaining to this kind of CW system. These include: (1) Is alum sludge suitable for reuse in CWs? (2) Is Al released from the sludge a concern? (3) What is the lifespan of the alum sludge in CWs? (4) How can P be recovered from the used alum sludge? (5) Does clogging happen in alum sludge-based CW systems and what is the solution?

  18. Instrumentation issues in implementation science.

    PubMed

    Martinez, Ruben G; Lewis, Cara C; Weiner, Bryan J

    2014-09-04

    Like many new fields, implementation science has become vulnerable to instrumentation issues that potentially threaten the strength of the developing knowledge base. For instance, many implementation studies report findings based on instruments that do not have established psychometric properties. This article aims to review six pressing instrumentation issues, discuss the impact of these issues on the field, and provide practical recommendations. This debate centers on the impact of the following instrumentation issues: use of frameworks, theories, and models; role of psychometric properties; use of 'home-grown' and adapted instruments; choosing the most appropriate evaluation method and approach; practicality; and need for decision-making tools. Practical recommendations include: use of consensus definitions for key implementation constructs; reporting standards (e.g., regarding psychometrics, instrument adaptation); when to use multiple forms of observation and mixed methods; and accessing instrument repositories and decision aid tools. This debate provides an overview of six key instrumentation issues and offers several courses of action to limit the impact of these issues on the field. With careful attention to these issues, the field of implementation science can potentially move forward at the rapid pace that is respectfully demanded by community stakeholders.

  19. ERCMExpress. Volume 3, Issue 4

    ERIC Educational Resources Information Center

    Taymans, Mary Frances; McDonald, Dale

    2007-01-01

    The Emergency Response and Crisis Management (ERCM) Technical Assistance Center's "ERCMExpress" is a newsletter that provides comprehensive information on key issues in school emergency management. This issue, entitled "Emergency Management Opportunities and Challenges for Non-Public Schools," examines integrating non-public…

  20. Sulfur, a Key Water Quality Issue in the Everglades

    NASA Astrophysics Data System (ADS)

    Orem, W. H.; Lerch, H. E.; Bates, A. L.; Corum, M.; Beck, M.; Kleckner, S.

    2002-05-01

    Sulfur is an important water quality issue in the Everglades because of its role in microbial sulfate reduction and the methylation of mercury. Methylmercury (MeHg), a neurotoxin that is bioaccumulated, has been found in high concentrations in freshwater fish from the Everglades, and poses a potential threat to fish-eating wildlife and to human health through fish consumption. Sulfur appears to play a key role in regulating both the magnitude and distribution of MeHg in the Everglades. Freshwater wetlands typically have low sulfur concentrations, but marshes in portions of the northern Everglades have average surface water sulfate concentrations of 60 mg/l, compared to 1 mg/l or less at background sites. Marsh areas with excess sulfate are concentrated near sites of canal discharge and along canal levees. The canal water that is discharged into the marshes appears to be the major source of excess sulfate entering the Everglades. This canal water drains the Everglades Agricultural Area (EAA) and has sulfate concentrations averaging over 70 mg/l and periodically approaching 200 mg/l. We used sulfate concentration data and the sulfur (d34S) isotopic composition of sulfate in marsh surface water, canal water, rainwater, and groundwater to trace the source of the excess sulfate entering the Everglades. Results show that canal water from the EAA is the major source of excess sulfate entering the Everglades. Furthermore, canal water with the highest sulfate concentrations had d34S values of +16 per mil, similar to the d34S signature of agricultural sulfur used as a soil amendment in the EAA. Rainwater has too little sulfate to account for the high sulfate concentrations observed in the canals and in large portions of the Everglades. Groundwater beneath the present day Everglades generally has either too low a sulfate concentration or a d34S signature that is inconsistent with that of surface water in the Everglades. The excess sulfate entering the Everglades from canal

  1. Alcohol & drug abuse: Revisiting employee assistance programs and substance use problems in the workplace: key issues and a research agenda.

    PubMed

    Merrick, Elizabeth S Levy; Volpe-Vartanian, Joanna; Horgan, Constance M; McCann, Bernard

    2007-10-01

    This column describes employee assistance program (EAPs) and identifies key issues for contemporary EAPs. These programs began as occupational alcohol programs and have evolved into more comprehensive resources. To better understand contemporary EAPs, the authors suggest a research agenda that includes descriptive studies to provide an up-to-date picture of services; investigations of how contemporary EAPs address substance use problems, including management consultation for early identification; further study of EAPs' effects on outcomes, such as productivity and work group outcomes; examination of the relationship between EAPs and other workplace resources; further examination of influences on EAP utilization; and development and testing of EAP performance measures.

  2. Body Dysmorphic Disorder: Some Key Issues for DSM-V

    PubMed Central

    Phillips, Katharine A.; Wilhelm, Sabine; Koran, Lorrin M.; Didie, Elizabeth R.; Fallon, Brian A.; Feusner, Jamie; Stein, Dan J.

    2014-01-01

    Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with an imagined or slight defect in appearance, has been described for more than a century and increasingly studied over the past several decades. This paper provides a focused review of issues pertaining to BDD that are relevant to DSM-V. The review presents a number of options and preliminary recommendations to be considered for DSM-V: 1) Criterion A may benefit from some rewording, without changing its focus or meaning; 2) Potential disadvantages of adding a new criterion to reflect BDD compulsive behaviors seem to outweigh potential advantages, but adding such a criterion remains an option that can be considered; 3) A clinical significance criterion seems necessary for BDD to differentiate it from normal appearance concerns; 4) BDD and eating disorders have some overlapping features and need to be differentiated; some minor changes to DSM-IV’s criterion C are suggested; 5) BDD should not be broadened to include body integrity identity disorder (apotemnophilia) or olfactory reference syndrome; 6) There is no compelling evidence for including diagnostic features or subtypes that are specific to gender-related, age-related, or cultural manifestations of BDD; 7) Adding muscle dysmorphia as a specifier may have clinical utility; and 8) The ICD-10 criteria for hypochondriacal disorder are not suitable for BDD, and there is no empirical evidence that BDD and hypochondriasis are the same disorder. The issue of how BDD’s delusional variant should be classified in DSM-V is briefly discussed and will be addressed more extensively in a separate paper. PMID:20533368

  3. Body dysmorphic disorder: some key issues for DSM-V.

    PubMed

    Phillips, Katharine A; Wilhelm, Sabine; Koran, Lorrin M; Didie, Elizabeth R; Fallon, Brian A; Feusner, Jamie; Stein, Dan J

    2010-06-01

    Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with an imagined or slight defect in appearance, has been described for more than a century and increasingly studied over the past several decades. This article provides a focused review of issues pertaining to BDD that are relevant to DSM-V. The review presents a number of options and preliminary recommendations to be considered for DSM-V: (1) Criterion A may benefit from some rewording, without changing its focus or meaning; (2) There are both advantages and disadvantages to adding a new criterion to reflect compulsive BDD behaviors; this possible addition requires further consideration; (3) A clinical significance criterion seems necessary for BDD to differentiate it from normal appearance concerns; (4) BDD and eating disorders have some overlapping features and need to be differentiated; some minor changes to DSM-IV's criterion C are suggested; (5) BDD should not be broadened to include body integrity identity disorder (apotemnophilia) or olfactory reference syndrome; (6) There is no compelling evidence for including diagnostic features or subtypes that are specific to gender-related, age-related, or cultural manifestations of BDD; (7) Adding muscle dysmorphia as a specifier may have clinical utility; and (8) The ICD-10 criteria for hypochondriacal disorder are not suitable for BDD, and there is no empirical evidence that BDD and hypochondriasis are the same disorder. The issue of how BDD's delusional variant should be classified in DSM-V is briefly discussed and will be addressed more extensively in a separate article. (c) 2010 Wiley-Liss, Inc.

  4. Gender equality and sustainable human development are key issues.

    PubMed

    Ando, H

    1995-01-01

    In a message to the Indochina Women's Parliamentarians Meeting, Hirofumi Ando, Deputy Executive Director of the United Nations Family Planning Association (UNFPA), encouraged participants to link gender equality and development issues. Ando noted that many of the goals of the 1994 International Conference on Population and Development imply recognition of the need to redress gender inequalities and empower women. The Program of Action adopted in Cairo requires countries to achieve universal access to primary education and reproductive health care services. Parliamentarians in attendance were urged to mobilize the financial resources and political will necessary to implement programs in these areas.

  5. Development of Improved Caprock Integrity and Risk Assessment Techniques

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

    Bruno, Michael

    GeoMechanics Technologies has completed a geomechanical caprock integrity analysis and risk assessment study funded through the US Department of Energy. The project included: a detailed review of historical caprock integrity problems experienced in the natural gas storage industry; a theoretical description and documentation of caprock integrity issues; advanced coupled transport flow modelling and geomechanical simulation of three large-scale potential geologic sequestration sites to estimate geomechanical effects from CO₂ injection; development of a quantitative risk and decision analysis tool to assess caprock integrity risks; and, ultimately the development of recommendations and guidelines for caprock characterization and CO₂ injection operating practices. Historicalmore » data from gas storage operations and CO₂ sequestration projects suggest that leakage and containment incident risks are on the order of 10-1 to 10-2, which is higher risk than some previous studies have suggested for CO₂. Geomechanical analysis, as described herein, can be applied to quantify risks and to provide operating guidelines to reduce risks. The risk assessment tool developed for this project has been applied to five areas: The Wilmington Graben offshore Southern California, Kevin Dome in Montana, the Louden Field in Illinois, the Sleipner CO₂ sequestration operation in the North Sea, and the In Salah CO₂ sequestration operation in North Africa. Of these five, the Wilmington Graben area represents the highest relative risk while the Kevin Dome area represents the lowest relative risk.« less

  6. The Value Added National Project. Technical Report: Primary 4. Value-Added Key Stage 1 to Key Stage 2.

    ERIC Educational Resources Information Center

    Tymms, Peter

    This is the fourth in a series of technical reports that have dealt with issues surrounding the possibility of national value-added systems for primary schools in England. The main focus has been on the relative progress made by students between the ends of Key Stage 1 (KS1) and Key Stage 2 (KS2). The analysis has indicated that the strength of…

  7. Summary of Key Issues Raised in the Technology for Early Awareness of Addiction and Mental Illness (TEAAM-I) Meeting.

    PubMed

    Baumel, Amit; Baker, Justin; Birnbaum, Michael L; Christensen, Helen; De Choudhury, Munmun; Mohr, David C; Muench, Fred; Schlosser, Danielle; Titov, Nick; Kane, John M

    2018-05-01

    Technology provides an unparalleled opportunity to remove barriers to earlier identification and engagement in services for mental and addictive disorders by reaching people earlier in the course of illness and providing links to just-in-time, cost-effective interventions. Achieving this opportunity, however, requires stakeholders to challenge underlying assumptions about traditional pathways to mental health care. In this Open Forum, the authors highlight key issues discussed in the Technology for Early Awareness of Addiction and Mental Illness (TEAAM-I) meeting-held October 13-14, 2016, in New York City-that are related to three identified areas in which technology provides important and unique opportunities to advance early identification, increase service engagement, and decrease the duration of untreated mental and addictive disorders.

  8. The study of key issues about integration of GNSS and strong-motion records for real-time earthquake monitoring

    NASA Astrophysics Data System (ADS)

    Tu, Rui; Zhang, Pengfei; Zhang, Rui; Liu, Jinhai

    2016-08-01

    This paper has studied the key issues about integration of GNSS and strong-motion records for real-time earthquake monitoring. The validations show that the consistence of the coordinate system must be considered firstly to exclude the system bias between GNSS and strong-motion. The GNSS sampling rate is suggested about 1-5 Hz, and we should give the strong-motion's baseline shift with a larger dynamic noise as its variation is very swift. The initialization time of solving the baseline shift is less than one minute, and ambiguity resolution strategy is not greatly improved the solution. The data quality is very important for the solution, we advised to use multi-frequency and multi-system observations. These ideas give an important guide for real-time earthquake monitoring and early warning by the tight integration of GNSS and strong-motion records.

  9. Earth Sciences Division Research Summaries 2002-2003

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

    Bodvarsson, G.S.

    2003-11-01

    Research in earth and atmospheric sciences is becoming increasingly important in light of the energy, climate change, and environmental issues facing the United States and the world. The development of new energy resources other than hydrocarbons and the safe disposal of nuclear waste and greenhouse gases (such as carbon dioxide and methane) are critical to the future energy needs and environmental safety of this planet. In addition, the cleanup of many contaminated sites in the U.S., along with the preservation and management of our water supply, remain key challenges for us as well as future generations. Addressing these energy, climatemore » change, and environmental issues requires the timely integration of earth sciences' disciplines (such as geology, hydrology, oceanography, climatology, geophysics, geochemistry, geomechanics, ecology, and environmental sciences). This integration will involve focusing on fundamental crosscutting concerns that are common to many of these issues. A primary focus will be the characterization, imaging, and manipulation of fluids in the earth. Such capabilities are critical to many DOE applications, from environmental restoration to energy extraction and optimization. The Earth Sciences Division (ESD) of the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) is currently addressing many of the key technical issues described above. In this document, we present summaries of many of our current research projects. While it is not a complete accounting, it is representative of the nature and breadth of our research effort. We are proud of our scientific efforts, and we hope that you will find our research useful and exciting. Any comments on our research are appreciated and can be sent to me personally. This report is divided into five sections that correspond to the major research programs in the Earth Sciences Division: (1) Fundamental and Exploratory Research; (2) Nuclear Waste; (3) Energy Resources; (4

  10. Geomechanics-Based Stochastic Analysis of Injection- Induced Seismicity

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

    Ghassemi, Ahmad

    The production of geothermal energy from dry and low permeability reservoirs is achieved by water circulation in natural and/or man-made fractures, and is referred to as enhanced or engineered geothermal systems (EGS). Often, the permeable zones have to be created by stimulation, a process which involves fracture initiation and/or activation of discontinuities such as faults and joints due to pore pressure and the in-situ stress perturbations. The stimulation of a rock mass is often accompanied by multiple microseismic events. Micro-seismic events associated with rock failure in shear, and shear slip on new or pre-existing fracture planes and possibly their propagations.more » The microseismic signals contain information about the sources of energy that can be used for understanding the hydraulic fracturing process and the created reservoir properties. Detection and interpretation of microseismic events is useful for estimating the stimulated zone, created reservoir permeability and fracture growth, and geometry of the geological structures and the in-situ stress state. The process commonly is referred to as seismicity-based reservoir characterization (SBRC). Although, progress has been made by scientific & geothermal communities for quantitative and qualitative analysis of reservoir stimulation using SBRC several key questions remain unresolved in the analysis of micro-seismicity namely, variation of seismic activity with injection rate, delayed micro-seismicity, and the relation of stimulated zone to the injected volume and its rate, and the resulting reservoir permeability. In addition, the current approach to SBRC does not consider the full range of relevant poroelastic and thermoelastic phenomena and neglects the uncertainty in rock properties and in-situ stress in the data inversion process. The objective of this research and technology developments was to develop a 3D SBRC model that addresses these shortcomings by taking into account hydro

  11. Ethical issues in the export, storage and reuse of human biological samples in biomedical research: perspectives of key stakeholders in Ghana and Kenya.

    PubMed

    Tindana, Paulina; Molyneux, Catherine S; Bull, Susan; Parker, Michael

    2014-10-18

    For many decades, access to human biological samples, such as cells, tissues, organs, blood, and sub-cellular materials such as DNA, for use in biomedical research, has been central in understanding the nature and transmission of diseases across the globe. However, the limitations of current ethical and regulatory frameworks in sub-Saharan Africa to govern the collection, export, storage and reuse of these samples have resulted in inconsistencies in practice and a number of ethical concerns for sample donors, researchers and research ethics committees. This paper examines stakeholders' perspectives of and responses to the ethical issues arising from these research practices. We employed a qualitative strategy of inquiry for this research including in-depth interviews and focus group discussions with key research stakeholders in Kenya (Nairobi and Kilifi), and Ghana (Accra and Navrongo). The stakeholders interviewed emphasised the compelling scientific importance of sample export, storage and reuse, and acknowledged the existence of some structures governing these research practices, but they also highlighted the pressing need for a number of practical ethical concerns to be addressed in order to ensure high standards of practice and to maintain public confidence in international research collaborations. These concerns relate to obtaining culturally appropriate consent for sample export and reuse, understanding cultural sensitivities around the use of blood samples, facilitating a degree of local control of samples and sustainable scientific capacity building. Drawing on these findings and existing literature, we argue that the ethical issues arising in practice need to be understood in the context of the interactions between host research institutions and local communities and between collaborating institutions. We propose a set of 'key points-to-consider' for research institutions, ethics committees and funding agencies to address these issues.

  12. Comparison of Fracture Gradient Methods for the FutureGen 2.0 Carbon Storage Site, Ill., USA.

    NASA Astrophysics Data System (ADS)

    Appriou, D.; Spane, F.; Wurstner White, S.; Kelley, M. E.; Sullivan, E. C.; Bonneville, A.; Gilmore, T. J.

    2014-12-01

    As part of a first-of-its-kind carbon dioxide storage project, FutureGen Industrial Alliance is planning to inject 1.1 MMt/yr of supercritical CO2 over a 20-year period within a 1240 m deep saline aquifer (Mount Simon Sandstone) located in Morgan County, Illinois, USA. Numerous aspects of the design and operational activities of the CO2 storage site are dependent on the geomechanical properties of the targeted reservoir zone, as well as of the overlying confining zone and the underlying crystalline Precambrian basement. Detailed determination of the state-of-stress within the subsurface is of paramount importance in successfully designing well drilling/completion aspects, as well as assessing the risk of induced seismicity and the potential for creating and/or reopening pre-existing fractures; all of which help ensure the safe long-term storage of injected CO2. The quantitative determination of the subsurface fracture gradient is one of the key geomechanical parameters for the site injection design and operational limits (e.g., maximum safe injection pressure). A characterization well drilled in 2011 provides subsurface geomechanical characterization information for the FutureGen 2.0 site, and includes: 1) continuous elastic properties inferred from sonic/acoustic wireline logs 2) discrete depth geomechanical laboratory core measurements and 3) results obtained from hydraulic fracturing tests of selected borehole/depth-intervals. In this paper, the precise fracture gradients derived from borehole geomechanical test results are compared with semi-empirical, fracture gradient calculation/relationships based on elastic property wireline surveys and laboratory geomechanical core test results. Implications for using various fracture-gradients obtained from the different methods are assessed using PNNL's subsurface multiphase flow and transport simulator STOMP-CO2. The implications for operational activities at the site (based on using different fracture gradients) are

  13. ERCMExpress. Volume 3, Issue 2

    ERIC Educational Resources Information Center

    Schonfeld, David J.

    2007-01-01

    The Emergency Response and Crisis Management (ERCM) Technical Assistance Center's newsletter, "ERCMExpress," provides comprehensive information on key issues in school emergency management. This issue of "ERCMExpress," titled "Coping with the Death of a Student or Staff Member," highlights the range of impact death can have on a school community;…

  14. Key Skills and Competencies. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers on key skills and competencies and human resource development (HRD). "Career Related Competencies" (Marinka A.C.T. Kuijpers) reports findings from surveys completed by Dutch employees who identified these issues: self-reflection is more important than career control; age and gender influence attitude…

  15. Experimental Study and Computational Simulations of Key Pebble Bed Thermo-mechanics Issues for Design and Safety

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

    Tokuhiro, Akira; Potirniche, Gabriel; Cogliati, Joshua

    2014-07-08

    An experimental and computational study, consisting of modeling and simulation (M&S), of key thermal-mechanical issues affecting the design and safety of pebble-bed (PB) reactors was conducted. The objective was to broaden understanding and experimentally validate thermal-mechanic phenomena of nuclear grade graphite, specifically, spheres in frictional contact as anticipated in the bed under reactor relevant pressures and temperatures. The contact generates graphite dust particulates that can subsequently be transported into the flowing gaseous coolent. Under postulated depressurization transients and with the potential for leaked fission products to be adsorbed onto graphite 'dust', there is the potential for fission products to escapemore » from the primary volume. This is a design safety concern. Furthermore, earlier safety assessment identified the distinct possibility for the dispersed dust to combust in contact with air if sufficient conditions are met. Both of these phenomena were noted as important to design review and containing uncertainty to warrant study. The team designed and conducted two separate effects tests to study and benchmark the potential dust-generation rate, as well as study the conditions under which a dust explosion may occure in a standardized, instrumented explosion chamber.« less

  16. Current Issues Survey Report, 2007

    ERIC Educational Resources Information Center

    Camp, John S.; DeBlois, Peter B.

    2007-01-01

    The Eighth Annual EDUCAUSE Current Issues Survey asked campus information technology leaders to rate the most critical IT challenges facing them, their campuses, and/or their systems. Four findings associated with all respondents to this year's survey merit special mention. First, for the 2007 survey, the CIC decided to split a key issue choice…

  17. Geomechanical characterization of the Upper Carboniferous under thermal stress for the evaluation of a High Temperature - Mine Thermal Energy Storage (HT-MTES)

    NASA Astrophysics Data System (ADS)

    Hahn, Florian; Brüggemann, Nina; Bracke, Rolf; Alber, Michael

    2017-04-01

    The goal of this R&D project is to create a technically and economically feasible conceptual model for a High Temperature - Mine Thermal Energy Storage (HT-MTES) for the energetic reuse of a mine on the example of the Prosper-Haniel coal mine in Bottrop, Germany. This project is funded by the "Initiative Energy Storage" program of the German Federal Ministries BMWi, BMU and BMBF. At the end of 2018, the last operative coal mine in North Rhine-Westphalia, Germany (Prosper-Haniel), is going to be closed down, plugged and abandoned. Large amounts of subsurface infrastructures, resembled mainly by open parts of former galleries and mining faces are going to be flooded, after the mine is closed down and therefore have the potential to become an enormous geothermal reservoir for a seasonal heat storage. During the summer non-used (waste) heat from solar thermal power plants, garbage incineration, combined heat and power plants (CHP) or industrial production processes can be stored within dedicated drifts of the mine. During the winter season, this surplus heat can be extracted and directly utilized in commercial and/or residential areas. For the evaluation of such a HT-MTES within a former coal mine, the corresponding geomechanical parameters of the Upper Carboniferous under thermal stress needs to be evaluated. Therefore the main rock types of the Upper Carboniferous (claystone, siltstone and sandstone) are subject to a geomechanical characterization before and after thermal cyclic loadings of temperatures up to 200 °C. The samples have been collected directly from the coal mine Prosper-Haniel within a depth range of 1000 - 1200 m. Unconfined compressive and tensile strengths, as well as triaxial tests were performed at room temperature. Furthermore, a range of petrophysical properties like density, thin-section analysis and P-wave velocities were determined. First results show an indication that the overall strength properties of the samples are not effected by

  18. Key Cognitive Issues in the Design of Electronic Displays of Instrument Approach Procedure Charts

    DOT National Transportation Integrated Search

    1993-11-01

    This report provides a general introduction to the field of cognitive psychology and the application of well researched cognitive issues to the design of electronic instrument approach procedures (EIAP) displays. It presents 46 cognitive issues and 1...

  19. Geomechanical behavior of the reservoir and caprock system at the In Salah CO2 storage project.

    PubMed

    White, Joshua A; Chiaramonte, Laura; Ezzedine, Souheil; Foxall, William; Hao, Yue; Ramirez, Abelardo; McNab, Walt

    2014-06-17

    Almost 4 million metric tons of CO2 were injected at the In Salah CO2 storage site between 2004 and 2011. Storage integrity at the site is provided by a 950-m-thick caprock that sits above the injection interval. This caprock consists of a number of low-permeability units that work together to limit vertical fluid migration. These are grouped into main caprock units, providing the primary seal, and lower caprock units, providing an additional buffer and some secondary storage capacity. Monitoring observations at the site indirectly suggest that pressure, and probably CO2, have migrated upward into the lower portion of the caprock. Although there are no indications that the overall storage integrity has been compromised, these observations raise interesting questions about the geomechanical behavior of the system. Several hypotheses have been put forward to explain the measured pressure, seismic, and surface deformation behavior. These include fault leakage, flow through preexisting fractures, and the possibility that injection pressures induced hydraulic fractures. This work evaluates these hypotheses in light of the available data. We suggest that the simplest and most likely explanation for the observations is that a portion of the lower caprock was hydrofractured, although interaction with preexisting fractures may have played a significant role. There are no indications, however, that the overall storage complex has been compromised, and several independent data sets demonstrate that CO2 is contained in the confinement zone.

  20. Reservoir creep and induced seismicity: inferences from geomechanical modeling of gas depletion in the Groningen field

    NASA Astrophysics Data System (ADS)

    van Wees, Jan-Diederik; Osinga, Sander; Van Thienen-Visser, Karin; Fokker, Peter A.

    2018-03-01

    The Groningen gas field in the Netherlands experienced an immediate reduction in seismic events in the year following a massive cut in production. This reduction is inconsistent with existing models of seismicity predictions adopting compaction strains as proxy, since reservoir creep would then result in a more gradual reduction of seismic events after a production stop. We argue that the discontinuity in seismic response relates to a physical discontinuity in stress loading rate on faults upon the arrest of pressure change. The stresses originate from a combination of the direct poroelastic effect through the pressure changes and the delayed effect of ongoing compaction after cessation of reservoir production. Both mechanisms need to be taken into account. To this end, we employed finite-element models in a workflow that couples Kelvin-Chain reservoir creep with a semi-analytical approach for the solution of slip and seismic moment from the predicted stress change. For ratios of final creep and elastic compaction up to 5, the model predicts that the cumulative seismic moment evolution after a production stop is subject to a very moderate increase, 2-10 times less than the values predicted by the alternative approaches using reservoir compaction strain as proxy. This is in agreement with the low seismicity in the central area of the Groningen field immediately after reduction in production. The geomechanical model findings support scope for mitigating induced seismicity through adjusting rates of pressure change by cutting down production.

  1. The Causes of Poverty: Thinking Critically about a Key Economic Issue

    ERIC Educational Resources Information Center

    Otlin, Josh

    2008-01-01

    Economics is a central part of civic education. Students need to know about the Constitution and the party system, but active citizenship in the twenty-first century requires much more than the standard civics courses offer. Economic issues dominate public policy debates ranging from Social Security to immigration to international security. If…

  2. Key Issues in Empirically Identifying Chronically Low-Performing and Turnaround Schools

    ERIC Educational Resources Information Center

    Hansen, Michael

    2012-01-01

    One of the US Department of Education's key priorities is turning around the nation's persistently low-achieving schools, yet exactly how to identify low-performing schools is a task left to state policy makers, and a myriad of definitions have been utilized. In addition, exactly how to recognize when a school begins to turn around is not well…

  3. Key Issues in the Role of Peroxisome Proliferator–Activated Receptor Agonism and Cell Signaling in Trichloroethylene Toxicity

    PubMed Central

    Keshava, Nagalakshmi; Caldwell, Jane C.

    2006-01-01

    Peroxisome proliferator–activated receptor α (PPARα) is thought to be involved in several different diseases, toxic responses, and receptor pathways. The U.S. Environmental Protection Agency 2001 draft trichloroethylene (TCE) risk assessment concluded that although PPAR may play a role in liver tumor induction, the role of its activation and the sequence of subsequent events important to tumorigenesis are not well defined, particularly because of uncertainties concerning the extraperoxisomal effects. In this article, which is part of a mini-monograph on key issues in the health risk assessment of TCE, we summarize some of the scientific literature published since that time on the effects and actions of PPARα that help inform and illustrate the key scientific questions relevant to TCE risk assessment. Recent analyses of the role of PPARα in gene expression changes caused by TCE and its metabolites provide only limited data for comparison with other PPARα agonists, particularly given the difficulties in interpreting results involving PPARα knockout mice. Moreover, the increase in data over the last 5 years from the broader literature on PPARα agonists presents a more complex array of extraperoxisomal effects and actions, suggesting the possibility that PPARα may be involved in modes of action (MOAs) not only for liver tumors but also for other effects of TCE and its metabolites. In summary, recent studies support the conclusion that determinations of the human relevance and susceptibility to PPARα-related MOA(s) of TCE-induced effects cannot rely on inferences regarding peroxisome proliferation per se and require a better understanding of the interplay of extraperoxisomal events after PPARα agonism. PMID:16966106

  4. Key Issues in the Networking Field Today. Proceedings of the Library of Congress Network Advisory Committee Meeting (Washington, DC, May 6-8, 1985). Network Planning Paper No. 12.

    ERIC Educational Resources Information Center

    Library of Congress, Washington, DC. Network Development Office.

    The May 1985 program session of the Library of Congress Network Advisory Committee focused on the identification of key issues in the networking field. Presentations included discussions of major network developments in the last two decades, the changing network players, the impact of technology on networks, and library networks and the law. The…

  5. Integrity of Pre-existing Wellbores in Geological Sequestration of CO 2 – Assessment Using a Coupled Geomechanics-fluid Flow Model

    DOE PAGES

    Kelkar, Sharad; Carey, J. William; Dempsey, David; ...

    2014-12-31

    Assessment of potential CO 2 and brine leakage from wellbores is central to any consideration of the viability of geological CO 2 sequestration. Depleted oil and gas reservoirs are some of the potential candidates for consideration as sequestration sites. The sequestration sites are expected to cover laterally extensive areas to be of practical interest. Hence there is a high likelihood that such sites will contain many pre-existing abandoned wells. Most existing work on wellbore integrity has focused on field and laboratory studies of chemical reactivity. Very little work has been done on the impacts of mechanical stresses on wellbore performance.more » This study focuses on the potential enhancement of fluid flow pathways in the near-wellbore environment due to modifications in the geomechanical stress field resulting from the CO 2 injection operations. The majority of the operational scenarios for CO 2 sequestration lead to significant rise in the formation pore pressure. This is expected to lead to an expansion of the reservoir rock and build-up of shear stresses near wellbores where the existence of cement and casing are expected to constrain the expansion. If the stress buildup is large enough, this can lead to failure with attendant permeability enhancement that can potentially provide leakage pathways to shallower aquifers and the surface. In this study, we use a numerical model to simulate key features of a wellbore (casing, annulus and cement) embedded in a system that includes the upper aquifer, caprock, and storage aquifer. We present the sensitivity of damage initiation and propagation to various operational and formation parameters. We consider Mohr-Coulomb shear-failure models; tensile failure is also likely to occur but will require higher stress changes and will be preceded by shear failure. The modeling is performed using the numerical simulator FEHM developed at LANL that models coupled THM processes during multi-phase fluid flow and

  6. Geomechanical effects on CO 2 leakage through fault zones during large-scale underground injection

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

    Rinaldi, Antonio P.; Rutqvist, Jonny; Cappa, Frédéric

    2013-12-01

    The importance of geomechanics—including the potential for faults to reactivate during large-scale geologic carbon sequestration operations—has recently become more widely recognized. However, notwithstanding the potential for triggering notable (felt) seismic events, the potential for buoyancy-driven CO 2 to reach potable groundwater and the ground surface is actually more important from public safety and storage-efficiency perspectives. In this context, this paper extends the previous studies on the geomechanical modeling of fault responses during underground carbon dioxide injection, focusing on the short-term integrity of the sealing caprock, and hence on the potential for leakage of either brine or CO 2 to reachmore » the shallow groundwater aquifers during active injection. We consider stress/strain-dependent permeability and study the leakage through the fault zone as its permeability changes during a reactivation, also causing seismicity. We analyze several scenarios related to the volume of CO 2 injected (and hence as a function of the overpressure), involving both minor and major faults, and analyze the profile risks of leakage for different stress/strain-permeability coupling functions. We conclude that whereas it is very difficult to predict how much fault permeability could change upon reactivation, this process can have a significant impact on the leakage rate. Moreover, our analysis shows that induced seismicity associated with fault reactivation may not necessarily open up a new flow path for leakage. Results show a poor correlation between magnitude and amount of fluid leakage, meaning that a single event is generally not enough to substantially change the permeability along the entire fault length. Finally, and consequently, even if some changes in permeability occur, this does not mean that the CO 2 will migrate up along the entire fault, breaking through the caprock to enter the overlying aquifer.« less

  7. For Dr. Nancy Snyderman's Parents, Staying Close to Family Is Key

    MedlinePlus

    ... Issues Feature: Senior Living For Dr. Nancy Snyderman's Parents, Staying Close to Family Is Key Past Issues / ... home. "Watching my children grow closer to my parents has been a blessing, and having us nearby ...

  8. Safe and inclusive research practices for qualitative research involving people with dementia: A review of key issues and strategies.

    PubMed

    Novek, Sheila; Wilkinson, Heather

    2017-01-01

    Aim Developing strategies to ensure the safe participation of people with dementia in research is critical to support their wider inclusion in research and to advance knowledge in the areas of dementia policy and practice. Objectives This literature review synthesizes and critically appraises different approaches to promote the safe participation of people with dementia in qualitative research. Methods Two databases were searched for articles that discuss the methodological or ethical aspects of qualitative research involving people with dementia. We did not focus on informed consent or ethical review processes as these have been reviewed elsewhere. Findings Key issues that impact participant safety include: language, gatekeepers, the research relationship, communication, dealing with distress, knowledge dissemination, and researcher skills. Conclusion By synthesizing different approaches to safety and highlighting areas of debate, we hope to advance discussion and to contribute to the development of inclusive research methods.

  9. Special issue : safety advancements

    DOT National Transportation Integrated Search

    1999-04-24

    This issue of 'Status Report' focuses on some of the most recent key safety technology improvements. The crash protection in passenger vehicles is improving substantially; advanced frontal airbags will soon be available in a number of models and side...

  10. Bridging the Gap between Health and Social Care for Rare Diseases: Key Issues and Innovative Solutions.

    PubMed

    Castro, Raquel; Senecat, Juliette; de Chalendar, Myriam; Vajda, Ildikó; Dan, Dorica; Boncz, Béata

    2017-01-01

    Bridging the gaps between health and social care for rare diseases is not only necessary but crucial to increase the life expectancy, quality of life and autonomy of people living with a rare disease, supporting them in the full realisation of their fundamental human rights.The complexity of rare diseases, their strong relation to disability and the current unmet social and daily life needs of people living with a rare disease must not be underestimated and require urgent attention from all stakeholders involved in care provision, from healthcare to social and community services.The Commission Expert Group Recommendations to Support the Incorporation of Rare Diseases into Social Services and Policies, adopted unanimously in April 2016, by the representatives of European Member States and the other rare disease stakeholders, clearly set the tone for the need to promote measures that facilitate multidisciplinary, holistic, continuous, person-centred and participative care provision to people living with rare diseases.These recommendations, sided by other recent policy developments at European and national levels, represent an important policy step into approaching rare diseases' complex challenges in regards to holistic care provision.Innovative approaches aiming at bridging the gap between health, social and community service and support providers are currently being developed and tested in different European countries: standards of care, networks of expertise, case management services, one-stop-shop services, amongst others.These ongoing pilot approaches, presented in this chapter, have the power to inspire future policies and the effective and efficient implementation of holistic care pathways for people living with a rare disease, bringing about significant changes for patients, carers, care providers, competent authorities and the society at large.Nonetheless, the challenges to fully address this issue remain numerous and other key issues will also need to be

  11. Mathematical Problem Solving. Issues in Research.

    ERIC Educational Resources Information Center

    Lester, Frank K., Jr., Ed.; Garofalo, Joe, Ed.

    This set of papers was originally developed for a conference on Issues and Directions in Mathematics Problem Solving Research held at Indiana University in May 1981. The purpose is to contribute to the clear formulation of the key issues in mathematical problem-solving research by presenting the ideas of actively involved researchers. An…

  12. Sustainable Sourcing of Global Agricultural Raw Materials: Assessing Gaps in Key Impact and Vulnerability Issues and Indicators

    PubMed Central

    Springer, Nathaniel P.; Garbach, Kelly; Guillozet, Kathleen; Haden, Van R.; Hedao, Prashant; Hollander, Allan D.; Huber, Patrick R.; Ingersoll, Christina; Langner, Megan; Lipari, Genevieve; Mohammadi, Yaser; Musker, Ruthie; Piatto, Marina; Riggle, Courtney; Schweisguth, Melissa; Sin, Emily; Snider, Sara; Vidic, Nataša; White, Aubrey; Brodt, Sonja; Quinn, James F.; Tomich, Thomas P.

    2015-01-01

    Understanding how to source agricultural raw materials sustainably is challenging in today’s globalized food system given the variety of issues to be considered and the multitude of suggested indicators for representing these issues. Furthermore, stakeholders in the global food system both impact these issues and are themselves vulnerable to these issues, an important duality that is often implied but not explicitly described. The attention given to these issues and conceptual frameworks varies greatly—depending largely on the stakeholder perspective—as does the set of indicators developed to measure them. To better structure these complex relationships and assess any gaps, we collate a comprehensive list of sustainability issues and a database of sustainability indicators to represent them. To assure a breadth of inclusion, the issues are pulled from the following three perspectives: major global sustainability assessments, sustainability communications from global food companies, and conceptual frameworks of sustainable livelihoods from academic publications. These terms are integrated across perspectives using a common vocabulary, classified by their relevance to impacts and vulnerabilities, and categorized into groups by economic, environmental, physical, human, social, and political characteristics. These issues are then associated with over 2,000 sustainability indicators gathered from existing sources. A gap analysis is then performed to determine if particular issues and issue groups are over or underrepresented. This process results in 44 “integrated” issues—24 impact issues and 36 vulnerability issues —that are composed of 318 “component” issues. The gap analysis shows that although every integrated issue is mentioned at least 40% of the time across perspectives, no issue is mentioned more than 70% of the time. A few issues infrequently mentioned across perspectives also have relatively few indicators available to fully represent them

  13. CTE's Role in Urban Education. Issue Brief

    ERIC Educational Resources Information Center

    Association for Career and Technical Education (ACTE), 2012

    2012-01-01

    This Issue Brief explores the promising role that career and technical education programs play in addressing key student achievement issues facing urban schools. CTE programs engage urban students by providing rigorous and relevant coursework, fostering positive relationships, establishing clear pathways and connecting education and…

  14. Keys to Transition: The California Model.

    ERIC Educational Resources Information Center

    Kearly, Patt

    This publication addresses basic issues related to the concept of transition as it is applied to students with disabilities in California. Following a pretest (and its answer key), the document uses a question and answer format to discuss common concerns about transition, normalization, the school role, the "Bridges" model developed by…

  15. Water Infrastructure Needs and Investment: Review and Analysis of Key Issues

    DTIC Science & Technology

    2008-11-24

    the Rural Development Act of 1972, as amended (7 U.S.C. § 1926). The purpose of these USDA programs is to provide basic amenities, alleviate health...nonregulatory costs (e.g., routine replacement of basic infrastructure).12 Wastewater Needs. The most recent wastewater survey, conducted in 2004 and issued...1.6 billion just to implement the most basic steps needed to improve security (such as better controlling access to facilities with fences, locks

  16. Geomechanics of Hydraulic Stimulation in Geothermal Systems: Designing and Implementing a Successful Enhanced Geothermal System at Desert Peak, Nevada

    NASA Astrophysics Data System (ADS)

    Hickman, S. H.; Davatzes, N. C.; Zemach, E.; Chabora, E.; Lutz, S.; Rose, P.; Majer, E. L.; Robertson-Tait, A.

    2013-12-01

    Creation of an Enhanced Geothermal System (EGS) in hot but low-permeability rocks involves hydraulic stimulation of fracture permeability to develop a complex heat exchange system with low hydraulic impedance. An integrated study of stress, fractures and rock mechanical properties was conducted to develop the geomechanical framework for a multi-stage EGS stimulation in Desert Peak well 27-15, located at the low-permeability margins of an active geothermal field. The stimulation targeted silicified tuffs and metamorphosed mudstones at depths of 0.9 to 1.8 km and temperatures ~180 to 210° C. Drilling-induced tensile fractures in image logs from well 27-15 show that the least horizontal principal stress (Shmin) is consistent with normal faulting on ESE- and WNW-dipping fractures mapped at the surface and seen in the image logs. A hydraulic fracturing stress measurement indicates that the magnitude of Shmin at ~0.93 km depth is 0.61 of the calculated vertical stress. Coulomb failure calculations using these stresses together with measurements of friction and permeability on core predict that dilatant shear failure should be induced on pre-existing conjugate normal faults once pore pressures are increased ~2.5 MPa or more above ambient values, generating a zone of enhanced permeability elongated in the direction toward active geothermal wells ~0.5 km to the SSW. Hydraulic stimulation of well 27-15 began in September 2010 by injecting water into the open-hole interval between the casing shoe at 0.9 km depth and a temporary cement plug at 1.1 km. Stimulation was monitored by combined surface and down-hole seismic monitoring, inter-well tracer testing and periodic pressure-temperature-flowmeter logging. An initial stage of low-pressure (shear) stimulation was conducted for ~100 days at a series of pressure steps

  17. Key Issues and Policy Considerations in Promoting Lifelong Learning in Selected African Countries: Ethiopia, Kenya, Namibia, Rwanda and Tanzania. UIL Publication Series on Lifelong Learning Policies and Strategies. No. 1

    ERIC Educational Resources Information Center

    Walters, Shirley; Yang, Jim; Roslander, Peter

    2014-01-01

    This cross-national study focuses on key issues and policy considerations in promoting lifelong learning in Ethiopia, Kenya, Namibia, Rwanda, and Tanzania (the five African countries that took part in a pilot workshop on "Developing Capacity for Establishing Lifelong Learning Systems in UNESCO Member States: at the UNESCO Institute for…

  18. Listening for Prescriptions: A National Consultation on Pharmaceutical Policy Issues

    PubMed Central

    Morgan, Steve; Cunningham, Colleen M.

    2010-01-01

    Objectives and Methods: Pharmaceutical policy is an increasingly costly, essential and challenging component of health system management. We sought to identify priority pharmaceutical policy issues in Canada and to translate them into research priorities using key informant interviews, stakeholder surveys and a deliberative workshop. Results: We found consensus on overarching policy goals: to provide all Canadians with equitable and sustainable access to necessary medicines. We also found widespread frustration that many key pharmaceutical policy issues in Canada — including improving prescription drug financing and pricing — have been persistent challenges owing to a lack of policy coordination. The coverage of extraordinarily costly medicines for serious conditions was identified as a rapidly emerging policy issue. Conclusion: Targeted research and knowledge translation activities can help address key policy issues and, importantly, challenges of policy coordination in Canada and thereby reduce inequity and inefficiency in policy approaches and outcomes. PMID:22043223

  19. New Stark regulations: Key issues for health care decision-makers.

    PubMed

    Johnson, B A; Niederman, G A; Bowman, L E; McCullough, A C

    1998-01-01

    On Jan. 9, 1998, The Health Care Financing Administration (HCFA) issued long-awaited Proposed Regulations for what has become known as Stark II. The regulations are subject to a comment period and later refinement. However, they lay out HCFA's basic understanding of what kinds of practices constitute an illegal kickback. In general terms, the law prohibits physicians from referring Medicare or Medicaid patients to entities with which they (or an immediate family member) have a "financial relationship" for the delivery of a specific list of designated health services. There are, however, exceptions also included in the new proposal. Group practices will want to pay special attention to HCFA's new definition of group practice.

  20. A Cross-Continental Study on Children's Drawings of Football Players: Implications for Understanding Key Issues and Controversies in Human Figure Drawings

    PubMed Central

    Baluch, Bahman; Duffy, Linda J.; Badami, Rokhsareh; Pereira, Elisangela C. Ap

    2017-01-01

    Professionals examine various aspects of girls’ and boys’ drawings as a way of understanding their intelligence, personality and emotional state. However, the extent to which such measures could be universally generalised or attributed to a specific cultural norm is still a debatable issue. In the present study five key features of children’s drawings namely: the size (height) of the drawings, profile or full face, figure in action or static, shaded or non-shaded and the nature of additional details were examined from a cross-cultural perspective, and by providing a topic (football) for which children’s drawing of a human figure could provide opportunities for the latter indices to manifest and flourish. Children from three countries; England, Iran and Brazil, representing three continents took part in this study. The participants were asked to draw a football player from their own country and from the other participating countries. The results showed that Brazilian children differ from Iranian and English children by drawing significantly smaller figures and putting more football action in the drawings. Shading of the figure drawn was more prevalent amongst English children. Such findings have implications for the interpretation of key aspects of children's drawings in educational, clinical and therapeutic settings and from a universal vs. culturally-specific viewpoint. PMID:28904595

  1. A Cross-Continental Study on Children's Drawings of Football Players: Implications for Understanding Key Issues and Controversies in Human Figure Drawings.

    PubMed

    Baluch, Bahman; Duffy, Linda J; Badami, Rokhsareh; Pereira, Elisangela C Ap

    2017-08-01

    Professionals examine various aspects of girls' and boys' drawings as a way of understanding their intelligence, personality and emotional state. However, the extent to which such measures could be universally generalised or attributed to a specific cultural norm is still a debatable issue. In the present study five key features of children's drawings namely: the size (height) of the drawings, profile or full face, figure in action or static, shaded or non-shaded and the nature of additional details were examined from a cross-cultural perspective, and by providing a topic (football) for which children's drawing of a human figure could provide opportunities for the latter indices to manifest and flourish. Children from three countries; England, Iran and Brazil, representing three continents took part in this study. The participants were asked to draw a football player from their own country and from the other participating countries. The results showed that Brazilian children differ from Iranian and English children by drawing significantly smaller figures and putting more football action in the drawings. Shading of the figure drawn was more prevalent amongst English children. Such findings have implications for the interpretation of key aspects of children's drawings in educational, clinical and therapeutic settings and from a universal vs. culturally-specific viewpoint.

  2. Protein analysis: key to the future.

    PubMed

    Boodhun, Nawsheen

    2018-05-01

    Protein analysis is crucial to elucidating the function of proteins and understanding the impact of their presence, absence and alteration. This is key to advancing knowledge about diseases, providing the opportunity for biomarker discovery and development of therapeutics. In this issue of Tech News, Nawsheen Boodhun explores the various means of protein analysis.

  3. A Citizen's Guide to U.S. Foreign Policy: Election '88. Nonpartisan Briefs on 18 Key Issues.

    ERIC Educational Resources Information Center

    Hoepli, Nancy, Ed.; And Others

    In order to make informed voting decisions citizens need background information on complex foreign policy issues facing the United States. This guide presents current issues and provides information to help citizens cast a thoughtful vote. The guide is divided into six main headings: Leadership; Security; Economic and Social Issues; Critical…

  4. Coherent one-way quantum key distribution

    NASA Astrophysics Data System (ADS)

    Stucki, Damien; Fasel, Sylvain; Gisin, Nicolas; Thoma, Yann; Zbinden, Hugo

    2007-05-01

    Quantum Key Distribution (QKD) consists in the exchange of a secrete key between two distant points [1]. Even if quantum key distribution systems exist and commercial systems are reaching the market [2], there are still improvements to be made: simplify the construction of the system; increase the secret key rate. To this end, we present a new protocol for QKD tailored to work with weak coherent pulses and at high bit rates [3]. The advantages of this system are that the setup is experimentally simple and it is tolerant to reduced interference visibility and to photon number splitting attacks, thus resulting in a high efficiency in terms of distilled secret bits per qubit. After having successfully tested the feasibility of the system [3], we are currently developing a fully integrated and automated prototype within the SECOQC project [4]. We present the latest results using the prototype. We also discuss the issue of the photon detection, which still remains the bottleneck for QKD.

  5. Afterschool: A Key to Successful Parent Engagement. MetLife Foundation Afterschool Alert. Issue Brief No. 57

    ERIC Educational Resources Information Center

    Afterschool Alliance, 2012

    2012-01-01

    The Afterschool Alliance, in partnership with MetLife Foundation, is proud to present the third in its latest series of four issue briefs examining critical issues facing middle school youth and the vital role afterschool programs play in addressing these issues. This brief explores afterschool and parent engagement. There is little dispute…

  6. Youth Physical Fitness: Ten Key Concepts

    ERIC Educational Resources Information Center

    Corbin, Charles B.; Welk, Gregory J.; Richardson, Cheryl; Vowell, Catherine; Lambdin, Dolly; Wikgren, Scott

    2014-01-01

    The promotion of physical fitness has been a key objective of physical education for more than a century. During this period, physical education has evolved to accommodate changing views on fitness and health. The purpose of this article is to discuss issues with fitness assessment and fitness education central to the new Presidential Youth…

  7. The 1986 NASP Survey: Comparison of Practitioners, NASP Leadership, and University Faculty on Key Issues.

    ERIC Educational Resources Information Center

    Reschly, Daniel J.; And Others

    National Association of School Psychologists (NASP) practitioner members (N=600), all recent members of the NASP leadership (N=139), and college faculty (N=166) responded to surveys on a variety of topics and issues including current demographic information, NASP priorities, credentialing, job satisfaction, issues related to learning disabilities…

  8. Continuing Education of the Professions: Issues, Ethics, and Conflicts

    ERIC Educational Resources Information Center

    Frandson, Phillip E.

    1975-01-01

    Relicensure has emerged as one of today's key issues in the continuing education of the professional. The conflict is clear: Who shall be controlling force? A grid involving the six issues focuses on the constituencies who seek to control these issues. The medical profession is used as an example. (BP)

  9. Key anticipated regulatory issues for clinical use of human induced pluripotent stem cells.

    PubMed

    Knoepfler, Paul S

    2012-09-01

    The production of human induced pluripotent stem cells (hiPSCs) has greatly expanded the realm of possible stem cell-based regenerative medicine therapies and has particularly exciting potential for autologous therapies. However, future therapies based on hiPSCs will first have to address not only similar regulatory issues as those facing human embryonic stem cells with the US FDA and international regulatory agencies, but also hiPSCs have raised unique concerns as well. While the first possible clinical use of hiPSCs remains down the road, as a field it would be wise for us to anticipate potential roadblocks and begin formulating solutions. In this article, I discuss the potential regulatory issues facing hiPSCs and propose some potential changes in the direction of the field in response.

  10. ERCMExpress. Volume 3, Issue 5

    ERIC Educational Resources Information Center

    Taylor, Matt

    2007-01-01

    The Emergency Response and Crisis Management (ECRM) Technical Assistance Center's newsletter "ERCMExpress" provides comprehensive information on key issues in school emergency management. Many nontraditional schools across the United States, such as storefront schools, rural schools, and alternative education facilities, face challenges…

  11. Key issues in space nuclear power challenges for the future

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W., Jr.

    1991-01-01

    The future appears rich in missions that will extend the frontiers of knowledge, human presence in space, and opportunities for profitable commerce. Key to the success of these ventures is the availability of plentiful, cost effective electric power and assured, low cost access to space. While forecasts of space power needs are problematic, an assessment of future needs based on terrestrial experience has been made. These needs fall into three broad categories: survival, self sufficiency, and industrialization. The cost of delivering payloads to orbital locations from LEO to Mars has been determined and future launch cost reductions projected. From these factors, then, projections of the performance necessary for future solar and nuclear space power options has been made. These goals are largely dependent upon orbital location and energy storage needs. Finally the cost of present space power systems has been determined and projections made for future systems.

  12. Early Care and Education Issues Rising to the Top.

    ERIC Educational Resources Information Center

    Walker, Sherry Freeland, Ed.

    2001-01-01

    Noting that growing consensus about the importance of the first 5 years of life has prompted in-depth considerations about the systemic quality of early care and education in the United States, this issue of "State Education Leader" examines various aspects of early learning. Topics considered in this issue are: (1) key issues in financing early…

  13. Clinical Trials: A Crucial Key to Human Health Research

    MedlinePlus

    ... Clinical Trials: A Crucial Key to Human Health Research Past Issues / Summer 2006 Table of Contents For ... Photo: PhotoDisc At the forefront of human health research today are clinical trials—studies that use human ...

  14. Current Chinese Leadership: Background, Associations, and Issues for Selected Key Military Leaders

    DTIC Science & Technology

    1985-09-01

    58 years old). Key leaders classified as conservative, such as Ye Jianying and Xu Xiangqian, lost their influential positions in September 1985...Cmte, CCP-CC (since Oct 83); VC, Central Greening Cmte (since Feb 82) Name;Jiang Xianchen Position; Deputy Chief, PLA GSD (since Mar 85) Name; Li ...Guang Position; Dir, Weapons & Equipment Dept, PLA GSD (since Nov 82) Name; Li Jing Position; Dep Cdr, PLA Navy (since Jul 83) Name; Li Jiulong

  15. Key issues in the computational simulation of GPCR function: representation of loop domains

    NASA Astrophysics Data System (ADS)

    Mehler, E. L.; Periole, X.; Hassan, S. A.; Weinstein, H.

    2002-11-01

    Some key concerns raised by molecular modeling and computational simulation of functional mechanisms for membrane proteins are discussed and illustrated for members of the family of G protein coupled receptors (GPCRs). Of particular importance are issues related to the modeling and computational treatment of loop regions. These are demonstrated here with results from different levels of computational simulations applied to the structures of rhodopsin and a model of the 5-HT2A serotonin receptor, 5-HT2AR. First, comparative Molecular Dynamics (MD) simulations are reported for rhodopsin in vacuum and embedded in an explicit representation of the membrane and water environment. It is shown that in spite of a partial accounting of solvent screening effects by neutralization of charged side chains, vacuum MD simulations can lead to severe distortions of the loop structures. The primary source of the distortion appears to be formation of artifactual H-bonds, as has been repeatedly observed in vacuum simulations. To address such shortcomings, a recently proposed approach that has been developed for calculating the structure of segments that connect elements of secondary structure with known coordinates, is applied to 5-HT2AR to obtain an initial representation of the loops connecting the transmembrane (TM) helices. The approach consists of a simulated annealing combined with biased scaled collective variables Monte Carlo technique, and is applied to loops connecting the TM segments on both the extra-cellular and the cytoplasmic sides of the receptor. Although this initial calculation treats the loops as independent structural entities, the final structure exhibits a number of interloop interactions that may have functional significance. Finally, it is shown here that in the case where a given loop from two different GPCRs (here rhodopsin and 5-HT2AR) has approximately the same length and some degree of sequence identity, the fold adopted by the loops can be similar. Thus

  16. Geomechanical Characterization and Modeling of the Newark Basin

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

    Collins, Daniel; Goldberg, Dave; Zakharova, Natalia

    Many effective techniques for evaluation if in-situ stress and geomechanical formation properties have been developed over the years but detailed understanding of these parameters in-situ, and standard characterization and monitoring protocols for carbon dioxide storage sites are lacking. A case study is performed in the northern Newark Basin, a candidate carbon dioxide-storage site located near the New York Metropolitan area. Possible impacts of seismic hazard and carbon dioxide leakage are particularly important due to a high population density across the basin. As one of the best-studied Mesozoic rift basins, the Newark Basin represents a great type locality for similar basinsmore » along the east coast and the results established in this project provide a robust tool for comparison to other Mesozoic basin data sets and locations (e.g., Georgia Rift Basin), where similar comprehensive core data sets and well testing results are not available. The project leveraged existing core samples to characterize and measure the strength of a series of differing lithologies and formations in the basin, with 28 samples fully tested. The orientation and magnitude of in-situ stresses were measured in an existing test well using a novel wireline tool set-up. This new methodology employed a “pre-stress” packer module to attempt to create an initial formation break using the force of the packer itself against the borehole wall. This enhancement in the testing methodology can be used in places where traditional methods are insufficient to break down a formation. Following the pre-stress packer sets, the improved Schlumberger Modular Formation Dynamics Tester tool-string was then used to perform traditional straddled formation breakdown testing of selected intervals. Testing indicated that formation breakdown was successfully achieved at two of the six test intervals, with an additional two tests sets indicating re-opening and propagation of pre-existing breaks out into the

  17. Time-related degradation, a key issue in nuclear plant safety evaluations

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

    Bonzon, L.L.; Bustard, L.D.; Clough, R.L.

    1982-01-01

    Sandia National Laboratories is conducting a number of programs under NRC sponsorship which deal with safety-related equipment qualification issues, including the important aspect of aging. Among these is the Qualification Testing Evaluation (QTE) program which was probably the first to devote significant effort towards aging research and was one of the primary motivators leading to the Workshop. The thrust of the QTE aging efforts has been on elastomeric materials, typically used in electrical cables, seals, gaskets, and the like; currently, efforts are being pursued on plant ambient environments measurements, aging of electronics, and aging of motors. A brief status reportmore » is presented in this paper.« less

  18. Data publication and dissemination of interactive keys under the open access model

    USDA-ARS?s Scientific Manuscript database

    The concepts of publication, citation and dissemination of interactive keys and other online keys are discussed and illustrated by a sample paper published in the present issue (doi: 10.3897/zookeys.21.271). The present model is based on previous experience with several existing examples of publishi...

  19. Foreign Affairs, Defense, and Trade: Key Issues for the 110th Congress

    DTIC Science & Technology

    2006-12-20

    granting Mexican trucks access to U.S. highways. Another long running dispute related to sugar and high - fructose corn syrup imports was recently resolved...and Mexico has agreed to repeal its 20% tax on soft drinks made with high - fructose corn syrup (HFCS). CRS Report RL32724, Mexico-U.S. Relations: Issues...reconstruction in those countries. After Iraq, other high priorities will be the continuing fight against terrorism and efforts to dissuade or restrain

  20. Simple group password-based authenticated key agreements for the integrated EPR information system.

    PubMed

    Lee, Tian-Fu; Chang, I-Pin; Wang, Ching-Cheng

    2013-04-01

    The security and privacy are important issues for electronic patient records (EPRs). The goal of EPRs is sharing the patients' medical histories such as the diagnosis records, reports and diagnosis image files among hospitals by the Internet. So the security issue for the integrated EPR information system is essential. That is, to ensure the information during transmission through by the Internet is secure and private. The group password-based authenticated key agreement (GPAKE) allows a group of users like doctors, nurses and patients to establish a common session key by using password authentication. Then the group of users can securely communicate by using this session key. Many approaches about GAPKE employ the public key infrastructure (PKI) in order to have higher security. However, it not only increases users' overheads and requires keeping an extra equipment for storing long-term secret keys, but also requires maintaining the public key system. This investigation presents a simple group password-based authenticated key agreement (SGPAKE) protocol for the integrated EPR information system. The proposed SGPAKE protocol does not require using the server or users' public keys. Each user only remembers his weak password shared with a trusted server, and then can obtain a common session key. Then all users can securely communicate by using this session key. The proposed SGPAKE protocol not only provides users with convince, but also has higher security.

  1. Managing the pursuit of health and wealth: the key challenges.

    PubMed

    Fidler, David P; Drager, Nick; Lee, Kelley

    2009-01-24

    This article forms part of a six-part Series on trade and health, and sets the stage for this Series by analysing key aspects of the relationship between trade and health. The Series takes stock of this relation and provides timely analysis of the key challenges facing efforts to achieve an appropriate balance between trade and health across a diverse range of issues. This introductory article reviews how trade and health have risen and expanded on global policy agendas in the past decade in unprecedented ways, describes how trade and health issues are respectively governed in international relations, examines the ongoing search for policy coherence between the two policy spheres, and highlights the topics of the remaining articles in the Series.

  2. Managing the pursuit of health and wealth: the key challenges

    PubMed Central

    Fidler, David P; Drager, Nick; Lee, Kelley

    2009-01-01

    This article forms part of a six-part Series on trade and health, and sets the stage for this Series by analysing key aspects of the relationship between trade and health. The Series takes stock of this relation and provides timely analysis of the key challenges facing efforts to achieve an appropriate balance between trade and health across a diverse range of issues. This introductory article reviews how trade and health have risen and expanded on global policy agendas in the past decade in unprecedented ways, describes how trade and health issues are respectively governed in international relations, examines the ongoing search for policy coherence between the two policy spheres, and highlights the topics of the remaining articles in the Series. PMID:19167061

  3. Cleaning by clustering: methodology for addressing data quality issues in biomedical metadata.

    PubMed

    Hu, Wei; Zaveri, Amrapali; Qiu, Honglei; Dumontier, Michel

    2017-09-18

    The ability to efficiently search and filter datasets depends on access to high quality metadata. While most biomedical repositories require data submitters to provide a minimal set of metadata, some such as the Gene Expression Omnibus (GEO) allows users to specify additional metadata in the form of textual key-value pairs (e.g. sex: female). However, since there is no structured vocabulary to guide the submitter regarding the metadata terms to use, consequently, the 44,000,000+ key-value pairs in GEO suffer from numerous quality issues including redundancy, heterogeneity, inconsistency, and incompleteness. Such issues hinder the ability of scientists to hone in on datasets that meet their requirements and point to a need for accurate, structured and complete description of the data. In this study, we propose a clustering-based approach to address data quality issues in biomedical, specifically gene expression, metadata. First, we present three different kinds of similarity measures to compare metadata keys. Second, we design a scalable agglomerative clustering algorithm to cluster similar keys together. Our agglomerative cluster algorithm identified metadata keys that were similar, based on (i) name, (ii) core concept and (iii) value similarities, to each other and grouped them together. We evaluated our method using a manually created gold standard in which 359 keys were grouped into 27 clusters based on six types of characteristics: (i) age, (ii) cell line, (iii) disease, (iv) strain, (v) tissue and (vi) treatment. As a result, the algorithm generated 18 clusters containing 355 keys (four clusters with only one key were excluded). In the 18 clusters, there were keys that were identified correctly to be related to that cluster, but there were 13 keys which were not related to that cluster. We compared our approach with four other published methods. Our approach significantly outperformed them for most metadata keys and achieved the best average F-Score (0

  4. Safe, Healthy and Ready to Succeed: Arizona School Readiness Key Performance Indicators

    ERIC Educational Resources Information Center

    Migliore, Donna E.

    2006-01-01

    "Safe, Healthy and Ready to Succeed: Arizona School Readiness Key Performance Indicators" presents a set of baseline measurements that gauge how well a statewide system of school readiness supports is addressing issues that affect Arizona children's readiness for school. The Key Performance Indicators (KPIs) measure the system, rather…

  5. International and domestic regulator issues facing the Canadian MSAT system

    NASA Technical Reports Server (NTRS)

    Bahman, Azarbar; Langlois, Jacques R.; Frank, Christopher J.

    1988-01-01

    International and domestic regulatory issues which affect the implementation of a mobile satellite system (MSAT) over North America are addressed. WARC-MOB-87, MSAT frequency co-ordination, frequency sharing and key Canadian domestic issues are discussed.

  6. Studying Petrophysical and Geomechanical Properties of Utica Point-Pleasant Shale and its Variations Across the Northern Appalachian Basin

    NASA Astrophysics Data System (ADS)

    Raziperchikolaee, S.; Kelley, M. E.; Burchwell, A.

    2017-12-01

    Understanding petrophysical and geomechanical parameters of shale formations and their variations across the basin are necessary to optimize the design of a hydraulic fracturing program aimed at enhancing long term oil/gas production from unconventional wells. Dipole sonic logging data (compressional-wave and shear-wave slowness) from multiple wells across the study area, coupled with formation bulk density log data, were used to calculate dynamic elastic parameters, including shear modulus, bulk modulus, Poisson's ratio, and Young's modulus for the shale formations. The individual-well data were aggregated into a single histogram for each parameter to gain an understanding of the variation in the properties (including brittleness) of the Utica Point-Pleasant formations across the entire study area. A crossplot of the compressional velocity and bulk density and a crossplot between the compressional velocity, the shear velocity, and depth of the measurement were used for a high level petrophysical characterization of the Utica Point-Pleasant. Detailed interpretation of drilling induced fractures recorded in image logs, and an analysis of shear wave anisotropy using multi-receiver sonic logs were also performed. Orientation of drilling induced fractures was measured to determine the maximum horizontal stress azimuth. Also, an analysis of shear wave anisotropy to predict stress anisotropy around the wellbore was performed to determine the direction of maximum horizontal stress. Our study shows how the detailed interpretation of borehole breakouts, drilling induced fractures, and sonic wave data can be used to reduce uncertainty and produce a better hydraulic fracturing design in the Utica Point Pleasant formations across the northern Appalachian Basin region of Ohio.

  7. Reproductive issues in anorexia nervosa

    PubMed Central

    Hoffman, Elizabeth R; Zerwas, Stephanie C; Bulik, Cynthia M

    2011-01-01

    Despite a high prevalence of menstrual irregularities, women with anorexia nervosa are becoming pregnant. The physical and psychological demands of pregnancy and motherhood can represent an immense challenge for women already struggling with the medical and psychological stress of an eating disorder. This article summarizes key issues related to reproduction in women with anorexia nervosa, highlighting the importance of preconception counseling, adequate gestational weight gain, and sufficient pre- and post-natal nutrition. Postpartum issues including eating disorder symptom relapse, weight loss, breastfeeding, and risk of perinatal depression and anxiety are also discussed. PMID:22003362

  8. Painful Joints? Early Treatment for Rheumatoid Arthritis Is Key

    MedlinePlus

    ... Print this issue Painful Joints? Early Treatment for Rheumatoid Arthritis Is Key En español Send us your comments ... type of arthritis. It’s far more common than rheumatoid arthritis. Osteoarthritis is caused by wear and tear on ...

  9. Issues and solutions: opportunities for European LED manufacturers

    NASA Astrophysics Data System (ADS)

    Pearsall, T. P.

    2007-09-01

    Marketing studies by EPIC show significant revenue opportunities by 2012 for UHB-LEDs in the automotive, LCD backlighting, and architectural lighting sectors. The goal of this workshop on manufacturing issues is to consider five key issues for UHB-LED manufacturing and to propose solutions that will pave the way to full exploitation of the opportunities.

  10. Communicative Language Testing: Current Issues and Future Research

    ERIC Educational Resources Information Center

    Harding, Luke

    2014-01-01

    This article discusses a range of current issues and future research possibilities in Communicative Language Testing (CLT) using, as its departure point, the key questions which emerged during the CLT symposium at the 2010 Language Testing Forum. The article begins with a summary of the 2010 symposium discussion in which three main issues related…

  11. Afghanistan: Key Oversight Issues

    DTIC Science & Technology

    2013-02-01

    2012. Afghan Security : Renewed Sharing of Biometric Data Could Strengthen U.S. Efforts to Protect U.S. Personnel from Afghan Security Force Attacks...SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as Report (SAR) 18. NUMBER OF PAGES 59 19a. NAME OF RESPONSIBLE PERSON...Afghanistan’s Security Environment 17 Enclosure II Transition of Lead Security to Afghan Security Forces 19 Enclosure III Future Cost and

  12. Developing Communities of Enquiry: Dealing with Social and Ethical Issues in Science at Key Stage 3

    ERIC Educational Resources Information Center

    Dunlop, Lynda; Humes, Gill; Clarke, Linda; Martin, Valerie McKelvey

    2011-01-01

    Reproductive technologies, drug discovery and exploration of the universe are areas of contemporary research that raise issues for individuals and society. Forward Thinking, Northern Ireland uses the development of communities of enquiry to promote discussion of these and other social and ethical issues in science with students aged 11-14 years.…

  13. Geomechanical Evaluation of Thermal Impact of Injected CO 2 Temperature on a Geological Reservoir: Application to the FutureGen 2.0 Site

    DOE PAGES

    Bonneville, Alain; USA, Richland Washington; Nguyen, Ba Nghiep; ...

    2014-12-31

    The impact of temperature variations of injected CO 2 on the mechanical integrity of a reservoir is a problem rarely addressed in the design of a CO 2 storage site. The geomechanical simulation of the FutureGen 2.0 storage site presented here takes into account the complete modeling of heat exchange between the environment and CO 2 during its transport in the pipeline and injection well before reaching the reservoir, as well as its interaction with the reservoir host rock. An ad-hoc program was developed to model CO 2 transport from the power plant to the reservoir and an approach couplingmore » PNNL STOMP-CO 2 multiphase flow simulator and ABAQUS® has been developed for the reservoir model which is fully three-dimensional with four horizontal wells and variable layer thickness. The Mohr-Coulomb fracture criterion has been employed, where hydraulic fracture was predicted to occur at an integration point if the fluid pressure at the point exceeded the least compressive principal stress. Evaluation of the results shows that the fracture criterion has not been verified at any node and time step for the CO 2 temperature range predicted at the top of the injection zone.« less

  14. Combining microseismic and geomechanical observations to interpret storage integrity at the In Salah CCS site

    NASA Astrophysics Data System (ADS)

    Goertz-Allmann, Bettina P.; Kühn, Daniela; Oye, Volker; Bohloli, Bahman; Aker, Eyvind

    2014-07-01

    We present results from microseismic monitoring and geomechanical analysis obtained at the industrial-scale CO2 sequestration site at the In Salah gas development project in Algeria. More than 5000 microseismic events have been detected at a pilot monitoring well using a master event cross-correlation method. The microseismic activity occurs in four distinct clusters and thereof three clearly correlate with injection rates and wellhead pressures. These event clusters are consistent with a location within the reservoir interval. However, due to insufficient network geometry there are large uncertainties on event location. We estimate a fracture pressure of 155 bar (at the wellhead) from the comparison of injection pressure and injection rate and conclude that reservoir fracture pressure of the injection horizon has most likely been exceeded occasionally, accompanied by increased microseismic activity. Our analysis of 3-D ray tracing for direct and converted phases suggests that one of the event clusters is located at a shallower depth than the reservoir injection interval. However, this event cluster is most likely unrelated to changes in the injection activity at a single well, as the event times do not correlate with the wellhead pressures. Furthermore, this event cluster shows b-values close to one, indicating re-activated natural or tectonic seismicity on pre-existing weakness zones rather than injection induced seismicity. Analysis of event azimuths and significant shear wave splitting of up to 5 per cent provide further valuable insight into fluid migration and fracture orientation at the reservoir level. Although only one geophone was available during the critical injection period, the microseismic monitoring of CO2 injection at In Salah is capable of addressing some of the most relevant questions about fluid migration and reservoir integrity. An improved monitoring array with larger aperture and higher sensitivity is highly recommended, as it could greatly

  15. Natural gas 1998: Issues and trends

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

    NONE

    Natural Gas 1998: Issues and Trends provides a summary of the latest data and information relating to the US natural gas industry, including prices, production, transmission, consumption, and the financial and environmental aspects of the industry. The report consists of seven chapters and five appendices. Chapter 1 presents a summary of various data trends and key issues in today`s natural gas industry and examines some of the emerging trends. Chapters 2 through 7 focus on specific areas or segments of the industry, highlighting some of the issues associated with the impact of natural gas operations on the environment. 57 figs.,more » 18 tabs.« less

  16. Sixty-Five Years of University Education in Nigeria: Some Key Cross Cutting Issues

    ERIC Educational Resources Information Center

    Ejoigu, Aloy; Sule, Sheidu

    2012-01-01

    This paper traces briefly the history and development of university education in Nigeria from one university in 1948 to a total of 118 universities as at the time of writing the paper. Besides the chronicle, the paper examines some cross-cutting issues that tend to scuttle the otherwise good intentions and robust programme initiatives of the…

  17. Tag Content Access Control with Identity-based Key Exchange

    NASA Astrophysics Data System (ADS)

    Yan, Liang; Rong, Chunming

    2010-09-01

    Radio Frequency Identification (RFID) technology that used to identify objects and users has been applied to many applications such retail and supply chain recently. How to prevent tag content from unauthorized readout is a core problem of RFID privacy issues. Hash-lock access control protocol can make tag to release its content only to reader who knows the secret key shared between them. However, in order to get this shared secret key required by this protocol, reader needs to communicate with a back end database. In this paper, we propose to use identity-based secret key exchange approach to generate the secret key required for hash-lock access control protocol. With this approach, not only back end database connection is not needed anymore, but also tag cloning problem can be eliminated at the same time.

  18. Examining Key Issues Underlying the Audit Commission Reports on SEN Policy Paper 1 (5th Series)

    ERIC Educational Resources Information Center

    Norwich, Brahm; Beek, Chris; Richardson, Penny; Gray, Peter

    2004-01-01

    This book is the first publication in the fifth series of seminars organised by the SEN Policy Options Steering Group to examine policy issues to do with special educational needs. The aim of the seminar was to examine in depth several underlying issues raised by the recent Audit Commission Reports on special educational needs. The seminar…

  19. Teaching Public Administration: Key Themes 1996-2016

    ERIC Educational Resources Information Center

    Fenwick, John

    2018-01-01

    In this article, the aim is to explore some of the key themes to emerge in the journal during the past two decades. Each selected theme will be reviewed in the light of issues raised in particular papers. The aim of this approach is, first, to facilitate reflection upon the contribution of the journal as its subject matter has moved from a concern…

  20. Geomechanical Analysis of Underground Coal Gasification Reactor Cool Down for Subsequent CO2 Storage

    NASA Astrophysics Data System (ADS)

    Sarhosis, Vasilis; Yang, Dongmin; Kempka, Thomas; Sheng, Yong

    2013-04-01

    Underground coal gasification (UCG) is an efficient method for the conversion of conventionally unmineable coal resources into energy and feedstock. If the UCG process is combined with the subsequent storage of process CO2 in the former UCG reactors, a near-zero carbon emission energy source can be realised. This study aims to present the development of a computational model to simulate the cooling process of UCG reactors in abandonment to decrease the initial high temperature of more than 400 °C to a level where extensive CO2 volume expansion due to temperature changes can be significantly reduced during the time of CO2 injection. Furthermore, we predict the cool down temperature conditions with and without water flushing. A state of the art coupled thermal-mechanical model was developed using the finite element software ABAQUS to predict the cavity growth and the resulting surface subsidence. In addition, the multi-physics computational software COMSOL was employed to simulate the cavity cool down process which is of uttermost relevance for CO2 storage in the former UCG reactors. For that purpose, we simulated fluid flow, thermal conduction as well as thermal convection processes between fluid (water and CO2) and solid represented by coal and surrounding rocks. Material properties for rocks and coal were obtained from extant literature sources and geomechanical testings which were carried out on samples derived from a prospective demonstration site in Bulgaria. The analysis of results showed that the numerical models developed allowed for the determination of the UCG reactor growth, roof spalling, surface subsidence and heat propagation during the UCG process and the subsequent CO2 storage. It is anticipated that the results of this study can support optimisation of the preparation procedure for CO2 storage in former UCG reactors. The proposed scheme was discussed so far, but not validated by a coupled numerical analysis and if proved to be applicable it could

  1. ERCMExpress. Volume 3, Issue 3

    ERIC Educational Resources Information Center

    Paine, Cathy

    2007-01-01

    The Emergency Response and Crisis Management (ERCM) Technical Assistance Center's newsletter, "ERCMExpress," provides comprehensive information on key issues in school emergency management. Memorials are deeply rooted in our culture and remind us of a person who has died or an event in which people died, and they provide a place for people to…

  2. Animal welfare: a complex domestic and international public-policy issue--who are the key players?

    PubMed

    Bayvel, A C David; Cross, Nicki

    2010-01-01

    Animal-welfare issues are usually portrayed in the media in a black-and-white fashion, with simple, single-perspective solutions proposed for what are often, in fact, complex policy issues. In this article, we argue that animal welfare is a multifaceted international and domestic public-policy issue that must take account of not only scientific, ethical, and economic issues but also religious, cultural, and international trade policy considerations. Management of animal welfare at a government policy level also requires an approach based on incremental change. Such change must be both science based and ethically principled, and the rate of change must recognize both the expectations of society and the constraints on the animal user. Ideally, such change should involve full ownership and buy-in from the affected animal user group. The range of stakeholders involved in the animal-welfare debate includes industry and producer groups, science bodies, and animal-welfare non-governmental organizations and professional groups, including the veterinary and legal professions. The veterinary profession, in particular, is expected to play an animal-welfare leadership role, and we discuss expectation versus reality at both a national and an international level. This latter discussion includes specific reference to the role of the World Organisation for Animal Health (the OIE) as an intergovernmental organization representing 175 countries and details some of the major achievements since the OIE assumed its international animal-welfare standard-setting role in 2002. We also address the role of the veterinary profession at national, regional, and international levels.

  3. Benthic boundary layer processes in the Lower Florida Keys

    USGS Publications Warehouse

    Lavoie, D.L.; Richardson, M.D.; Holmes, C.

    1997-01-01

    This special issue of Geo-Marine Letters, "Benthic Boundary Layer Processes in the Lower Florida Keys," includes 12 papers that present preliminary results from the Key West Campaign. The Dry Tortugas and Marquesas Keys test sites were selected by a group of 115 scientists and technicians to study benthic boundary layer processes in a carbonate environment controlled by bioturbation and biogeochemical processes. Major activities included remote sediment classification; high-frequency acoustic scattering experiments; sediment sampling for radiological, geotechnical, biological, biogeochemical, physical, and geoacoustic studies; and hydrodynamic studies using an instrumented tetrapod. All these data are being used to improve our understanding of the effects of environmental processes on sediment structure and behavior.

  4. Authenticated multi-user quantum key distribution with single particles

    NASA Astrophysics Data System (ADS)

    Lin, Song; Wang, Hui; Guo, Gong-De; Ye, Guo-Hua; Du, Hong-Zhen; Liu, Xiao-Fen

    2016-03-01

    Quantum key distribution (QKD) has been growing rapidly in recent years and becomes one of the hottest issues in quantum information science. During the implementation of QKD on a network, identity authentication has been one main problem. In this paper, an efficient authenticated multi-user quantum key distribution (MQKD) protocol with single particles is proposed. In this protocol, any two users on a quantum network can perform mutual authentication and share a secure session key with the assistance of a semi-honest center. Meanwhile, the particles, which are used as quantum information carriers, are not required to be stored, therefore the proposed protocol is feasible with current technology. Finally, security analysis shows that this protocol is secure in theory.

  5. Keys to soil taxonomy by soil survey staff (sixth edition)

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

    NONE

    1994-12-31

    This publication, Keys to Soil Taxonomy, serves two purposes. It provides the taxonomic keys necessary for the classification of soils according to Soil Taxonomy in a form that can be used easily in the field, and it also acquaints users of Soil Taxonomy with recent changes in the classification system. This volume includes all revisions of the keys that have so far been approved, replacing the original keys in Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys (1975), the work on which this abridged version, first published in 1983, is based. This publication incorporatesmore » all amendments approved to date and published in National Soil Taxonomy Handbook (NSTH) Issues 1-17.« less

  6. Ethical issues in animal cloning.

    PubMed

    Fiester, Autumn

    2005-01-01

    The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.

  7. Critical Issues and Key Points from the Survey to the Creation of the Historical Building Information Model: the Case of Santo Stefano Basilica

    NASA Astrophysics Data System (ADS)

    Castagnetti, C.; Dubbini, M.; Ricci, P. C.; Rivola, R.; Giannini, M.; Capra, A.

    2017-05-01

    The new era of designing in architecture and civil engineering applications lies in the Building Information Modeling (BIM) approach, based on a 3D geometric model including a 3D database. This is easier for new constructions whereas, when dealing with existing buildings, the creation of the BIM is based on the accurate knowledge of the as-built construction. Such a condition is allowed by a 3D survey, often carried out with laser scanning technology or modern photogrammetry, which are able to guarantee an adequate points cloud in terms of resolution and completeness by balancing both time consuming and costs with respect to the request of final accuracy. The BIM approach for existing buildings and even more for historical buildings is not yet a well known and deeply discussed process. There are still several choices to be addressed in the process from the survey to the model and critical issues to be discussed in the modeling step, particularly when dealing with unconventional elements such as deformed geometries or historical elements. The paper describes a comprehensive workflow that goes through the survey and the modeling, allowing to focus on critical issues and key points to obtain a reliable BIM of an existing monument. The case study employed to illustrate the workflow is the Basilica of St. Stefano in Bologna (Italy), a large monumental complex with great religious, historical and architectural assets.

  8. Issues in Distance Education: A Primer for Higher Education Decision Makers

    ERIC Educational Resources Information Center

    Beaudoin, Michael

    2016-01-01

    This chapter presents an overview of current issues related to distance learning in higher education. It identifies central questions, issues, challenges, and opportunities that must be addressed by decision makers, as well as key attributes of effective leaders.

  9. Issues in the Management of Distance Education.

    ERIC Educational Resources Information Center

    Murgatroyd, Stephen; Woudstra, Andrew

    1989-01-01

    Examines key issues facing administrators at Athabasca University and discusses their implications for distance education organizations. Topics discussed include strategic planning; accountability and cost effectiveness; consortia and cooperation; instructional design; managing technological innovation; marketing; quality assurance; and…

  10. Integrated Modeling and Experiments to Characterize Coupled Thermo-hydro-geomechanical-chemical processes in Hydraulic Fracturing

    NASA Astrophysics Data System (ADS)

    Viswanathan, H. S.; Carey, J. W.; Karra, S.; Porter, M. L.; Rougier, E.; Kang, Q.; Makedonska, N.; Hyman, J.; Jimenez Martinez, J.; Frash, L.; Chen, L.

    2015-12-01

    Hydraulic fracturing phenomena involve fluid-solid interactions embedded within coupled thermo-hydro-mechanical-chemical (THMC) processes over scales from microns to tens of meters. Feedbacks between processes result in complex dynamics that must be unraveled if one is to predict and, in the case of unconventional resources, facilitate fracture propagation, fluid flow, and interfacial transport processes. The proposed work is part of a broader class of complex systems involving coupled fluid flow and fractures that are critical to subsurface energy issues, such as shale oil, geothermal, carbon sequestration, and nuclear waste disposal. We use unique LANL microfluidic and triaxial core flood experiments integrated with state-of-the-art numerical simulation to reveal the fundamental dynamics of fracture-fluid interactions to characterize the key coupled processes that impact hydrocarbon production. We are also comparing CO2-based fracturing and aqueous fluids to enhance production, greatly reduce waste water, while simultaneously sequestering CO2. We will show pore, core and reservoir scale simulations/experiments that investigate the contolling mechanisms that control hydrocarbon production.

  11. Secure Cryptographic Key Management System (CKMS) Considerations for Smart Grid Devices

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

    Abercrombie, Robert K; Sheldon, Frederick T; Aldridge, Hal

    2011-01-01

    In this paper, we examine some unique challenges associated with key management in the Smart Grid and concomitant research initiatives: 1) effectively model security requirements and their implementations, and 2) manage keys and key distribution for very large scale deployments such as Smart Meters over a long period of performance. This will set the stage to: 3) develop innovative, low cost methods to protect keying material, and 4) provide high assurance authentication services. We will present our perspective on key management and will discuss some key issues within the life cycle of a cryptographic key designed to achieve the following:more » 1) control systems designed, installed, operated, and maintained to survive an intentional cyber assault with no loss of critical function, and 2) widespread implementation of methods for secure communication between remote access devices and control centers that are scalable and cost-effective to deploy.« less

  12. Passage Key Inlet, Florida; CMS Modeling and Borrow Site Impact Analysis

    DTIC Science & Technology

    2016-06-01

    Impact Analysis by Kelly R. Legault and Sirisha Rayaprolu PURPOSE: This Coastal and Hydraulics Engineering Technical Note (CHETN) describes the...use of a nested Coastal Modeling System (CMS) model for Passage Key Inlet, which is one of the connections between the Gulf of Mexico and Tampa Bay...driven sediment transport at Passage Key Inlet. This analysis resulted in issuing a new Florida Department of Environmental Protection (FDEP) permit to

  13. Effective user management with high strength crypto -key in dynamic group environment in cloud

    NASA Astrophysics Data System (ADS)

    Kumar, P. J.; Suganya, P.; Karthik, G.

    2017-11-01

    Cloud Clusters consists of various collections of files which are being accessed by multiple users of Cloud. The users are managed as a group and the association of the user to a particular group is dynamic in nature. Every group has a manager who handles the membership of a user to a particular group by issuing keys for encryption and decryption. Due to the dynamic nature of a user he/she may leave the group very frequently. But an attempt can be made by the user who has recently left the group to access a file maintained by that group. Key distribution becomes a critical issue while the behavior of the user is dynamic. Existing techniques to manage the users of group in terms of security and key distribution has been investigated so that to arrive at an objective to identify the scopes to increase security and key management scheme in cloud. The usage of various key combinations to measure the strength of security and efficiency of user management in dynamic cloud environment has been investigated.

  14. Gender, Literacy and Women's Empowerment in India: Some Issues

    ERIC Educational Resources Information Center

    Ghose, Malini

    2007-01-01

    The note discusses some key issues pertaining to gender, literacy and women's empowerment in India. It uses disaggregated data to illustrate the persisting gender disparities with regard to literacy and points out that despite this there is a lack of real political will to address issues of adult literacy. It further draws on data from the…

  15. Making Hawai'i's Kids Count. Issue Paper Number 3.

    ERIC Educational Resources Information Center

    Hawaii Univ., Manoa. Center on the Family.

    This issue paper from Hawai'i Kids Count addresses the issue of teen pregnancy and birth rates. The paper notes that teen pregnancy and birth rates are declining both nationally and in Hawaii and describes key risk factors associated with having a baby before age 20: (1) early school failure; (2) early behavioral problems; (3) family dysfunction;…

  16. BARI+: a biometric based distributed key management approach for wireless body area networks.

    PubMed

    Muhammad, Khaliq-ur-Rahman Raazi Syed; Lee, Heejo; Lee, Sungyoung; Lee, Young-Koo

    2010-01-01

    Wireless body area networks (WBAN) consist of resource constrained sensing devices just like other wireless sensor networks (WSN). However, they differ from WSN in topology, scale and security requirements. Due to these differences, key management schemes designed for WSN are inefficient and unnecessarily complex when applied to WBAN. Considering the key management issue, WBAN are also different from WPAN because WBAN can use random biometric measurements as keys. We highlight the differences between WSN and WBAN and propose an efficient key management scheme, which makes use of biometrics and is specifically designed for WBAN domain.

  17. The Role of Gender in the Socialization of Emotion: Key Concepts and Critical Issues

    ERIC Educational Resources Information Center

    Root, Amy Kennedy; Denham, Susanne A.

    2010-01-01

    Given the omnipresent role of gender in children's and adolescents' development, it seems necessary to better understand how gender affects the process of emotion socialization. In this introductory chapter, the authors discuss the overarching themes and key concepts discussed in this volume, as well as outline the distinct contribution of each…

  18. Predicting Key Events in the Popularity Evolution of Online Information.

    PubMed

    Hu, Ying; Hu, Changjun; Fu, Shushen; Fang, Mingzhe; Xu, Wenwen

    2017-01-01

    The popularity of online information generally experiences a rising and falling evolution. This paper considers the "burst", "peak", and "fade" key events together as a representative summary of popularity evolution. We propose a novel prediction task-predicting when popularity undergoes these key events. It is of great importance to know when these three key events occur, because doing so helps recommendation systems, online marketing, and containment of rumors. However, it is very challenging to solve this new prediction task due to two issues. First, popularity evolution has high variation and can follow various patterns, so how can we identify "burst", "peak", and "fade" in different patterns of popularity evolution? Second, these events usually occur in a very short time, so how can we accurately yet promptly predict them? In this paper we address these two issues. To handle the first one, we use a simple moving average to smooth variation, and then a universal method is presented for different patterns to identify the key events in popularity evolution. To deal with the second one, we extract different types of features that may have an impact on the key events, and then a correlation analysis is conducted in the feature selection step to remove irrelevant and redundant features. The remaining features are used to train a machine learning model. The feature selection step improves prediction accuracy, and in order to emphasize prediction promptness, we design a new evaluation metric which considers both accuracy and promptness to evaluate our prediction task. Experimental and comparative results show the superiority of our prediction solution.

  19. Internet Issues and Applications, 1997-1998.

    ERIC Educational Resources Information Center

    Dempsey, Bert J., Ed.; Jones, Paul, Ed.

    This book gives an overview of the leading-edge Internet application areas (streaming multimedia, collaborative tools, Web databases) and key information policy issues (privacy, censorship, information quality, and more). The text serves as a primer on understanding the forces--economic, legal, social, as well as technological--that are shaping…

  20. What Do People Know about Key Environmental Issues? A Review of Environmental Knowledge Surveys

    ERIC Educational Resources Information Center

    Robelia, Beth; Murphy, Tony

    2012-01-01

    This paper presents results from 15 little publicized state and national environmental surveys in the US that used similar questions. Our analysis reveals trends in adult understanding of environmental issues. These trends indicate that many may have difficulty making informed decisions about environmental policy as citizens, voters, and…

  1. Effective Schooling in Rural Africa Report 2: Key Issues Concerning School Effectiveness and Improvement.

    ERIC Educational Resources Information Center

    Saunders, Lesley

    This report presents an overview of the literature on school/teacher effectiveness and improvement, with a focus on implications for developing countries. Sections 1-2 discuss the trend toward site-based management, which has increased pressures on individual schools and their staff; eight key domains of school effectiveness; and the need to…

  2. Carbon Sequestration in Unconventional Reservoirs: Geophysical, Geochemical and Geomechanical Considerations

    NASA Astrophysics Data System (ADS)

    Zakharova, Natalia V.

    In the face of the environmental challenges presented by the acceleration of global warming, carbon capture and storage, also called carbon sequestration, may provide a vital option to reduce anthropogenic carbon dioxide emissions, while meeting the world's energy demands. To operate on a global scale, carbon sequestration would require thousands of geologic repositories that could accommodate billions of tons of carbon dioxide per year. In order to reach such capacity, various types of geologic reservoirs should be considered, including unconventional reservoirs such as volcanic rocks, fractured formations, and moderate-permeability aquifers. Unconventional reservoirs, however, are characterized by complex pore structure, high heterogeneity, and intricate feedbacks between physical, chemical and mechanical processes, and their capacity to securely store carbon emissions needs to be confirmed. In this dissertation, I present my contribution toward the understanding of geophysical, geochemical, hydraulic, and geomechanical properties of continental basalts and fractured sedimentary formations in the context of their carbon storage capacity. The data come from two characterization projects, in the Columbia River Flood Basalt in Washington and the Newark Rift Basin in New York, funded by the U.S. Department of Energy through Big Sky Carbon Sequestration Partnerships and TriCarb Consortium for Carbon Sequestration. My work focuses on in situ analysis using borehole geophysical measurements that allow for detailed characterization of formation properties on the reservoir scale and under nearly unaltered subsurface conditions. The immobilization of injected CO2 by mineralization in basaltic rocks offers a critical advantage over sedimentary reservoirs for long-term CO2 storage. Continental flood basalts, such as the Columbia River Basalt Group, possess a suitable structure for CO2 storage, with extensive reservoirs in the interflow zones separated by massive impermeable

  3. Information for Government Agencies about Specific Environmental Health Issues in Child-Care Settings

    EPA Pesticide Factsheets

    research on child care environmental health issues, identify key state and regional healthy child care organizations for partnerships, and see how other states are addressing child care environmental health issues.

  4. Consistent lithological units and its influence on geomechanical stratification in shale reservoir: case study from Baltic Basin, Poland.

    NASA Astrophysics Data System (ADS)

    Pachytel, Radomir; Jarosiński, Marek; Bobek, Kinga

    2017-04-01

    Geomechanical investigations in shale reservoir are crucial to understand rock behavior during hydraulic fracturing treatment and to solve borehole wall stability problem. Anisotropy should be considered as key mechanical parameter while trying to characterize shale properties in variety of scales. We are developing a concept of step-by-step approach to characterize and upscale the Consistent Lithological Units (CLU) at several scales of analysis. We decided that the most regional scale model, comparable to lithostratigraphic formations, is too general for hydraulic fracture propagation study thus a more detailed description is needed. The CLU's hierarchic model aims in upscale elastic properties with their anisotropy based on available data from vertical borehole. For the purpose of our study we have an access to continuous borehole core profile and full set of geophysical logging from several wells in the Pomeranian part of the Ordovician and Silurian shale complex belongs to the Baltic Basin. We are focused on shale properties that might be crucial for mechanical response to hydraulic fracturing: mineral components, porosity, density, elastic parameters and natural fracture pattern. To prepare the precise CLU model we compare several methods of determination and upscaling every single parameter used for consistent units secretion. Mineralogical data taken from ULTRA log, GEM log, X-ray diffraction and X-ray fluorescence were compared with Young modulus from sonic logs and Triaxial Compressive Strength Tests. The results showed the impact of clay content and porosity increase on Young's modulus reduction while carbonates (both calcite and dolomite) have stronger impact on elastic modulus growth, more than quartz, represented here mostly by detrital particles. Comparing the shales of similar composition in a few wells of different depths we concluded that differences in diagenesis and compaction due to variation in formation depth in a range of 1 km has negligible

  5. USSR Space Life Sciences Digest. Index to issues 10-14

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran

    1988-01-01

    An index is provided for issues 10 through 14 of the USSR Space Life Sciences Digest. There are two sections. The first section lists bibliographic citations of abstracts contained in the Digest issues covered grouped by topic area categories. The second section provides a key word index for the same set of abstracts.

  6. Emerging Issues in School, Family, & Community Connections. Annual Synthesis 2001

    ERIC Educational Resources Information Center

    Jordan, Catherine; Orozco, Evangelina; Averett, Amy

    2002-01-01

    This research synthesis is the first in a series that will examine key issues in the field of family and community connections with schools. The issues highlighted in this synthesis represent critical areas of work in family and community connections with schools where clarification, agreement, and further development are needed, as well as…

  7. Field demonstration of a continuous-variable quantum key distribution network.

    PubMed

    Huang, Duan; Huang, Peng; Li, Huasheng; Wang, Tao; Zhou, Yingming; Zeng, Guihua

    2016-08-01

    We report on what we believe is the first field implementation of a continuous-variable quantum key distribution (CV-QKD) network with point-to-point configuration. Four QKD nodes are deployed on standard communication infrastructures connected with commercial telecom optical fiber. Reliable key exchange is achieved in the wavelength-division-multiplexing CV-QKD network. The impact of a complex and volatile field environment on the excess noise is investigated, since excess noise controlling and reduction is arguably the major issue pertaining to distance and the secure key rate. We confirm the applicability and verify the maturity of the CV-QKD network in a metropolitan area, thus paving the way for a next-generation global secure communication network.

  8. Supply Issues for Science Academics in Australia: Now and in the Future

    ERIC Educational Resources Information Center

    Edwards, Daniel; Smith, T. Fred

    2010-01-01

    Australia, like the rest of the developed world, is in the midst of dealing with notable issues related to the age structure of its academic workforce. These issues are widespread and have been articulated in the Australian context most comprehensively by Hugo (2008). This paper investigates issues with demographic change and other key factors…

  9. Open-system dynamics of entanglement: a key issues review.

    PubMed

    Aolita, Leandro; de Melo, Fernando; Davidovich, Luiz

    2015-04-01

    One of the greatest challenges in the fields of quantum information processing and quantum technologies is the detailed coherent control over each and every constituent of quantum systems with an ever increasing number of particles. Within this endeavor, harnessing of many-body entanglement against the detrimental effects of the environment is a major pressing issue. Besides being an important concept from a fundamental standpoint, entanglement has been recognized as a crucial resource for quantum speed-ups or performance enhancements over classical methods. Understanding and controlling many-body entanglement in open systems may have strong implications in quantum computing, quantum simulations of many-body systems, secure quantum communication or cryptography, quantum metrology, our understanding of the quantum-to-classical transition, and other important questions of quantum foundations.In this paper we present an overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement under the influence of noise. Entanglement is thus taken as a dynamic quantity on its own, and we survey how it evolves due to the unavoidable interaction of the entangled system with its surroundings. We analyze several scenarios, corresponding to different families of states and environments, which render a very rich diversity of dynamical behaviors.In contrast to single-particle quantities, like populations and coherences, which typically vanish only asymptotically in time, entanglement may disappear at a finite time. In addition, important classes of entanglement display an exponential decay with the number of particles when subject to local noise, which poses yet another threat to the already-challenging scaling of quantum technologies. Other classes, however, turn out to be extremely robust against local noise. Theoretical results and recent experiments regarding the difference between local and global decoherence are summarized. Control and

  10. Open-system dynamics of entanglement:a key issues review

    NASA Astrophysics Data System (ADS)

    Aolita, Leandro; de Melo, Fernando; Davidovich, Luiz

    2015-04-01

    One of the greatest challenges in the fields of quantum information processing and quantum technologies is the detailed coherent control over each and every constituent of quantum systems with an ever increasing number of particles. Within this endeavor, harnessing of many-body entanglement against the detrimental effects of the environment is a major pressing issue. Besides being an important concept from a fundamental standpoint, entanglement has been recognized as a crucial resource for quantum speed-ups or performance enhancements over classical methods. Understanding and controlling many-body entanglement in open systems may have strong implications in quantum computing, quantum simulations of many-body systems, secure quantum communication or cryptography, quantum metrology, our understanding of the quantum-to-classical transition, and other important questions of quantum foundations. In this paper we present an overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement under the influence of noise. Entanglement is thus taken as a dynamic quantity on its own, and we survey how it evolves due to the unavoidable interaction of the entangled system with its surroundings. We analyze several scenarios, corresponding to different families of states and environments, which render a very rich diversity of dynamical behaviors. In contrast to single-particle quantities, like populations and coherences, which typically vanish only asymptotically in time, entanglement may disappear at a finite time. In addition, important classes of entanglement display an exponential decay with the number of particles when subject to local noise, which poses yet another threat to the already-challenging scaling of quantum technologies. Other classes, however, turn out to be extremely robust against local noise. Theoretical results and recent experiments regarding the difference between local and global decoherence are summarized. Control and

  11. Stress heterogeneity above and within a deep geothermal reservoir: From borehole observations to geomechanical modelling

    NASA Astrophysics Data System (ADS)

    Seithel, Robin; Peters, Max; Lesueur, Martin; Kohl, Thomas

    2017-04-01

    Overpressured reservoir conditions, local stress concentrations or a locally rotated stress field can initiate substantial problems during drilling or reservoir exploitation. Increasing geothermal utilization in the Molasse basin area in S-Germany is faced with such problems of deeply seated reservoir sections. In several wells, radial fluid flow systems are interpreted as highly porous layers. However, in nearby wells a combination of linear fluid flow, local stress heterogeneities and structural geology hint to a rather fault dominated reservoir (Seithel et al. 2015). Due to missing knowledge of the stress magnitude, stress orientation and their coupling to reservoir response, we will present a THMC model of critical formations and the geothermal reservoir targeting nearby faults. In an area south of Munich, where several geothermal wells are constructed, such wells are interpreted and integrated into a 30 x 30 km simulated model area. One of the main objectives here is to create a geomechanical reservoir model in a thermo-mechanical manner in order to understand the coupling between reservoir heterogeneities and stress distributions. To this end, stress analyses of wellbore data and laboratory tests will help to calibrate a reliable model. In order to implement the complex geological structure of the studied wedge-shaped foreland basin, an automatic export of lithology, fault and borehole data (e.g. from Petrel) into a FE mesh is used. We will present a reservoir-scale model that considers thermo-mechanic effects and analyze their influence on reservoir deformation, fluid flow and stress concentration. We use the currently developed finite element application REDBACK (https://github.com/pou036/redback), inside the MOOSE framework (Poulet et al. 2016). We show that mechanical heterogeneities nearby fault zones and their orientation within the stress field correlate to fracture pattern, interpreted stress heterogeneities or variegated flow systems within the

  12. Methodological Issues in Achieving School Accountability

    ERIC Educational Resources Information Center

    Linn, Robert L.

    2008-01-01

    Test-based educational accountability is widely used in many countries, but is pervasive in the US. Key features of test-based accountability required by the US No Child Left Behind Act are discussed. Particular attention is given to methodological issues such as the distinction between status and growth approaches, the setting of performance…

  13. Origins of life: a problem for physics, a key issues review

    NASA Astrophysics Data System (ADS)

    Imari Walker, Sara

    2017-09-01

    The origins of life stands among the great open scientific questions of our time. While a number of proposals exist for possible starting points in the pathway from non-living to living matter, these have so far not achieved states of complexity that are anywhere near that of even the simplest living systems. A key challenge is identifying the properties of living matter that might distinguish living and non-living physical systems such that we might build new life in the lab. This review is geared towards covering major viewpoints on the origin of life for those new to the origin of life field, with a forward look towards considering what it might take for a physical theory that universally explains the phenomenon of life to arise from the seemingly disconnected array of ideas proposed thus far. The hope is that a theory akin to our other theories in fundamental physics might one day emerge to explain the phenomenon of life, and in turn finally permit solving its origins.

  14. BARI+: A Biometric Based Distributed Key Management Approach for Wireless Body Area Networks

    PubMed Central

    Muhammad, Khaliq-ur-Rahman Raazi Syed; Lee, Heejo; Lee, Sungyoung; Lee, Young-Koo

    2010-01-01

    Wireless body area networks (WBAN) consist of resource constrained sensing devices just like other wireless sensor networks (WSN). However, they differ from WSN in topology, scale and security requirements. Due to these differences, key management schemes designed for WSN are inefficient and unnecessarily complex when applied to WBAN. Considering the key management issue, WBAN are also different from WPAN because WBAN can use random biometric measurements as keys. We highlight the differences between WSN and WBAN and propose an efficient key management scheme, which makes use of biometrics and is specifically designed for WBAN domain. PMID:22319333

  15. Key Issues Concerning Biolog Use for Aerobic and Anaerobic Freshwater Bacterial Community-Level Physiological Profiling

    NASA Astrophysics Data System (ADS)

    Christian, Bradley W.; Lind, Owen T.

    2006-06-01

    Bacterial heterotrophy in aquatic ecosystems is important in the overall carbon cycle. Biolog MicroPlates provide information into the metabolic potential of bacteria involved in carbon cycling. Specifically, Biolog EcoPlatesTM were developed with ecologically relevant carbon substrates to allow investigators to measure carbon substrate utilization patterns and develop community-level physiological profiles from natural bacterial assemblages. However, understanding of the functionality of these plates in freshwater research is limited. We explored several issues of EcoPlate use for freshwater bacterial assemblages including inoculum density, incubation temperature, non-bacterial color development, and substrate selectivity. Each of these has various effects on plate interpretation. We offer suggestions and techniques to resolve these interpretation issues. Lastly we propose a technique to allow EcoPlate use in anaerobic freshwater bacterial studies.

  16. Special Issue: "Molecules against Alzheimer".

    PubMed

    Decker, Michael; Muñoz-Torrero, Diego

    2016-12-16

    This Special Issue, entitled "Molecules against Alzheimer", gathers a number of original articles, short communications, and review articles on recent research efforts toward the development of novel drug candidates, diagnostic agents and therapeutic approaches for Alzheimer's disease (AD), the most prevalent neurodegenerative disorder and a leading cause of death worldwide. This Special Issue contains many interesting examples describing the design, synthesis, and pharmacological profiling of novel compounds that hit one or several key biological targets, such as cholinesterases, β-amyloid formation or aggregation, monoamine oxidase B, oxidative stress, biometal dyshomeostasis, mitochondrial dysfunction, serotonin and/or melatonin systems, the Wnt/β-catenin pathway, sigma receptors, nicotinamide phosphoribosyltransferase, or nuclear erythroid 2-related factor. The development of novel AD diagnostic agents based on tau protein imaging and the use of lithium or intranasal insulin for the prevention or the symptomatic treatment of AD is also covered in some articles of the Special Issue.

  17. Using Statistics to Explore Cross-Curricular and Social Issues Opportunities

    ERIC Educational Resources Information Center

    Day, Lorraine

    2013-01-01

    The area of statistics is one in which teachers may be encouraged to make important links to other curriculum areas and social issues. Statistical literacy is a key component of being numerate and living as an informed citizen. The teaching of statistics provides an opportunity to inform and educate students about social issues and moral…

  18. Digital telephony analysis model and issues

    NASA Astrophysics Data System (ADS)

    Keuthan, Lynn M.

    1995-09-01

    Experts in the fields of digital telephony and communications security have stated the need for an analytical tool for evaluating complex issues. Some important policy issues discussed by experts recently include implementing digital wire-taps, implementation of the 'Clipper Chip', required registration of encryption/decryption keys, and export control of cryptographic equipment. Associated with the implementation of these policies are direct costs resulting from implementation, indirect cost benefits from implementation, and indirect costs resulting from the risks of implementation or factors reducing cost benefits. Presented herein is a model for analyzing digital telephony policies and systems and their associated direct costs and indirect benefit and risk factors. In order to present the structure of the model, issues of national importance and business-related issues are discussed. The various factors impacting the implementation of the associated communications systems and communications security are summarized, and various implementation tradeoffs are compared based on economic benefits/impact. The importance of the issues addressed herein, as well as other digital telephony issues, has greatly increased with the enormous increases in communication system connectivity due to the advance of the National Information Infrastructure.

  19. Predicting Key Events in the Popularity Evolution of Online Information

    PubMed Central

    Fu, Shushen; Fang, Mingzhe; Xu, Wenwen

    2017-01-01

    The popularity of online information generally experiences a rising and falling evolution. This paper considers the “burst”, “peak”, and “fade” key events together as a representative summary of popularity evolution. We propose a novel prediction task—predicting when popularity undergoes these key events. It is of great importance to know when these three key events occur, because doing so helps recommendation systems, online marketing, and containment of rumors. However, it is very challenging to solve this new prediction task due to two issues. First, popularity evolution has high variation and can follow various patterns, so how can we identify “burst”, “peak”, and “fade” in different patterns of popularity evolution? Second, these events usually occur in a very short time, so how can we accurately yet promptly predict them? In this paper we address these two issues. To handle the first one, we use a simple moving average to smooth variation, and then a universal method is presented for different patterns to identify the key events in popularity evolution. To deal with the second one, we extract different types of features that may have an impact on the key events, and then a correlation analysis is conducted in the feature selection step to remove irrelevant and redundant features. The remaining features are used to train a machine learning model. The feature selection step improves prediction accuracy, and in order to emphasize prediction promptness, we design a new evaluation metric which considers both accuracy and promptness to evaluate our prediction task. Experimental and comparative results show the superiority of our prediction solution. PMID:28046121

  20. Issues for eHealth in Psychiatry: Results of an Expert Survey

    PubMed Central

    Huckvale, Kit; Larsen, Mark Erik; Basu, Ashna; Batterham, Philip J; Shaw, Frances; Sendi, Shahbaz

    2017-01-01

    Background Technology has changed the landscape in which psychiatry operates. Effective, evidence-based treatments for mental health care are now available at the fingertips of anyone with Internet access. However, technological solutions for mental health are not necessarily sought by consumers nor recommended by clinicians. Objective The objectives of this study are to identify and discuss the barriers to introducing eHealth technology-supported interventions within mental health. Methods An interactive polling tool was used to ask “In this brave new world, what are the key issues that need to be addressed to improve mental health (using technology)?” Respondents were the multidisciplinary attendees of the “Humans and Machines: A Quest for Better Mental Health” conference, held in Sydney, Australia, in 2016. Responses were categorized into 10 key issues using team-based qualitative analysis. Results A total of 155 responses to the question were received from 66 audience members. Responses were categorized into 10 issues and ordered by importance: access to care, integration and collaboration, education and awareness, mental health stigma, data privacy, trust, understanding and assessment of mental health, government and policy, optimal design, and engagement. In this paper, each of the 10 issues are outlined, and potential solutions are discussed. Many of the issues were interrelated, having implications for other key areas identified. Conclusions As many of the issues identified directly related to barriers to care, priority should be given to addressing these issues that are common across mental health delivery. Despite new challenges raised by technology, technology-supported mental health interventions represent a tremendous opportunity to address in a timely way these major concerns and improve the receipt of effective, evidence-based therapy by those in need. PMID:28246068

  1. Issues for eHealth in Psychiatry: Results of an Expert Survey.

    PubMed

    Nicholas, Jennifer; Huckvale, Kit; Larsen, Mark Erik; Basu, Ashna; Batterham, Philip J; Shaw, Frances; Sendi, Shahbaz

    2017-02-28

    Technology has changed the landscape in which psychiatry operates. Effective, evidence-based treatments for mental health care are now available at the fingertips of anyone with Internet access. However, technological solutions for mental health are not necessarily sought by consumers nor recommended by clinicians. The objectives of this study are to identify and discuss the barriers to introducing eHealth technology-supported interventions within mental health. An interactive polling tool was used to ask "In this brave new world, what are the key issues that need to be addressed to improve mental health (using technology)?" Respondents were the multidisciplinary attendees of the "Humans and Machines: A Quest for Better Mental Health" conference, held in Sydney, Australia, in 2016. Responses were categorized into 10 key issues using team-based qualitative analysis. A total of 155 responses to the question were received from 66 audience members. Responses were categorized into 10 issues and ordered by importance: access to care, integration and collaboration, education and awareness, mental health stigma, data privacy, trust, understanding and assessment of mental health, government and policy, optimal design, and engagement. In this paper, each of the 10 issues are outlined, and potential solutions are discussed. Many of the issues were interrelated, having implications for other key areas identified. As many of the issues identified directly related to barriers to care, priority should be given to addressing these issues that are common across mental health delivery. Despite new challenges raised by technology, technology-supported mental health interventions represent a tremendous opportunity to address in a timely way these major concerns and improve the receipt of effective, evidence-based therapy by those in need. ©Jennifer Nicholas, Kit Huckvale, Mark Erik Larsen, Ashna Basu, Philip J Batterham, Frances Shaw, Shahbaz Sendi. Originally published in the

  2. Starting a hospital-based home health agency: Part II--Key success factors.

    PubMed

    Montgomery, P

    1993-09-01

    In Part II of a three-part series, the financial, technological and legislative issues of a hospital-based home health-agency are discussed. Beginning a home healthcare service requires intensive research to answer key environmental and operational questions--need, competition, financial projections, initial start-up costs and the impact of delayed depreciation. Assessments involving technology, staffing, legislative and regulatory issues can help project service volume, productivity and cost-control.

  3. End-of-life care in advanced kidney disease: ethical and legal issues and key challenges for black and minority ethnic groups.

    PubMed

    Cronin, Antonia J

    2014-09-01

    Advances in modern medical technology have gone so far that it is now possible for machinery to keep people alive. To some extent this has led to a misperception in society that death can almost always be postponed because life-sustaining extracorporeal machinery of some sort or another, for example a dialysis machine, can prevent it. However, for some, being kept alive connected to a dialysis machine for four hours three times a week does not represent or even come close to an existence or quality of life they consider valuable. It may even cause unnecessary distress. This may be because they have reached a point at the end of their lives where they would like the focus of their treatment or care to become that which enables them to live as well as possible until they die. In these circumstances treatment and care should properly be that which enables the supportive and palliative care needs of both patient and family to be identified and met throughout the last phase of life and into bereavement. Identifying and acknowledging the importance of such a paradigm shift in the delivery of healthcare, and above all facilitating it, includes taking on the responsibility, incumbent upon us all, to address the ethical issues that are brought into focus. In this paper, I examine some of these issues. I consider the ways in which underlying theoretical ethical principles have informed the development of professional guidance and highlight the dynamic relationship this guidance has with the law. Finally, I demonstrate the ways in which it can be usefully applied to inform and assist clinical decision-making. Key challenges for BAME groups are addressed. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  4. NG9-1-1 transition issues report.

    DOT National Transportation Integrated Search

    2008-02-01

    A key outcome of the U.S. Department of Transportation (USDOT) Next Generation 9-1-1 : (NG9-1-1) Initiative is the identification of well-supported options and crucial transition issues : for migrating from todays 9-1-1 system to a NG9-1-1 system ...

  5. Exploring Ethical Issues Associated with Using Online Surveys in Educational Research

    ERIC Educational Resources Information Center

    Roberts, Lynne D.; Allen, Peter J.

    2015-01-01

    Online surveys are increasingly used in educational research, yet little attention has focused on ethical issues associated with their use in educational settings. Here, we draw on the broader literature to discuss 5 key ethical issues in the context of educational survey research: dual teacher/researcher roles; informed consent; use of…

  6. The National Issues Forum: Bridging the Human Gap through Innovative Learning.

    ERIC Educational Resources Information Center

    McMahan, Eva M.

    The National Issues Forum model, a series of community based public discussions on key domestic issues, may be a partial solution to the "human gap" between growing complexity and a capacity to deal with it, by exemplifying "innovative learning." To engage in innovative learning, characterized by anticipation and participation,…

  7. ISSUES IN SEDIMENT TOXICITY AND ECOLOGICAL RISK ASSESSMENT

    EPA Science Inventory

    This paper is based on a facilitated Workshop and Roundtable Discussion of key issues in sediment toxicology and ecological risk assessment (ERA) as applied to sediments that was held at the Conference on Dredged Material Management: Options and Environmental Considerations. The ...

  8. Issues in the study of intonation in language varieties.

    PubMed

    Warren, Paul

    2005-01-01

    Some key issues in the study of intonation in language varieties are presented and discussed with reference to recent research on the intonation of New Zealand English. The particular issues that are highlighted include the determination of the intonational phonological categories of a language variety, and the attribution of varietal differences as realizational differences between varieties or as systemic differences in the categories found to be present in each variety.

  9. Implementation of the NCSS Guidelines for Teaching Science-Related Social Issues: Exemplar Lessons.

    ERIC Educational Resources Information Center

    Otto, Robert A., Ed.

    This document contains the Guidelines for Teaching Science-Related Social Issues adopted in 1982 by the National Council for the Social Studies and 10 examplar lessons each keyed to particular guidelines and drawing upon contemporary issues. The premise upon which the guidelines are based is that science is a social issue and that the examination…

  10. Coupled Hydro-Mechanical Modeling of Fluid Geological Storage

    NASA Astrophysics Data System (ADS)

    Castelletto, N.; Garipov, T.; Tchelepi, H. A.

    2013-12-01

    The accurate modeling of the complex coupled physical processes occurring during the injection and the post-injection period is a key factor for assessing the safety and the feasibility of anthropogenic carbon dioxide (CO2) sequestration in subsurface formations. In recent years, it has become widely accepted the importance of the coupling between fluid flow and geomechanical response in constraining the sustainable pressure buildup caused by fluid injection relative to the caprock sealing capacity, induced seismicity effects and ground surface stability [e.g., Rutqvist, 2012; Castelletto et al., 2013]. Here, we present a modeling approach based on a suitable combination of Finite Volumes (FVs) and Finite Elements (FEs) to solve the coupled system of partial differential equations governing the multiphase flow in a deformable porous medium. Specifically, a FV method is used for the flow problem while the FE method is adopted to address the poro-elasto-plasticity equations. The aim of the present work is to compare the performance and the robustness of unconditionally stable sequential-implicit schemes [Kim et al., 2011] and the fully-implicit method in solving the algebraic systems arising from the discretization of the governing equations, for both normally conditioned and severely ill-conditioned problems. The two approaches are tested against well-known analytical solutions and experimented with in a realistic application of CO2 injection in a synthetic aquifer. References: - Castelletto N., G. Gambolati, and P. Teatini (2013), Geological CO2 sequestration in multi-compartment reservoirs: Geomechanical challenges, J. Geophys. Res. Solid Earth, 118, 2417-2428, doi:10.1002/jgrb.50180. - Kim J., H. A. Tchelepi, and R. Juanes (2011), Stability, accuracy and efficiency of sequential methods for coupled flow and geomechanics, SPE J., 16(2), 249-262. - Rutqvist J. (2012), The geomechanics of CO2 storage in deep sedimentary formations, Geotech. Geol. Eng., 30, 525-551.

  11. Ground thermal and geomechanical conditions in a permafrost-affected high-latitude rock avalanche site (Polvartinden, northern Norway)

    NASA Astrophysics Data System (ADS)

    Frauenfelder, Regula; Isaksen, Ketil; Lato, Matthew J.; Noetzli, Jeannette

    2018-04-01

    On 26 June 2008, a rock avalanche detached in the northeast facing slope of Polvartinden, a high-alpine mountain in Signaldalen, northern Norway. Here, we report on the observed and modelled past and present near-surface temperature regime close to the failure zone, as well as on a subsequent simulation of the subsurface temperature regime, and on initial geomechanical mapping based on laser scanning. The volume of the rock avalanche was estimated to be approximately 500 000 m3. The depth to the actual failure surface was found to range from 40 m at the back of the failure zone to 0 m at its toe. Visible in situ ice was observed in the failure zone just after the rock avalanche. Between September 2009 and August 2013, ground surface temperatures were measured with miniature temperature data loggers at 14 different localities, close to the original failure zone along the northern ridge of Polvartinden and on the valley floor. The results from these measurements and from a basic three-dimensional heat conduction model suggest that the lower altitudinal limit of permafrost at present is at 600-650 m a.s.l., which corresponds to the upper limit of the failure zone. A coupling of our in situ data with regional climate data since 1958 suggests a general gradual warming and that the period with highest mean near surface temperatures on record ended four months before the Signaldalen rock avalanche detached. A comparison with a transient permafrost model run at 10 m depth, representative for areas where snow accumulates, strengthen these findings, which are also in congruence with measurements in nearby permafrost boreholes. It is likely that permafrost in and near the failure zone is presently subject to degradation. This degradation, in combination with the extreme warm year antecedent to the rock failure, is seen to have played an important role in the detaching of the Signaldalen rock avalanche.

  12. Habitability during long-duration space missions - Key issues associated with a mission to Mars

    NASA Technical Reports Server (NTRS)

    Stuster, Jack

    1989-01-01

    Isolation and confinement conditions similar to those of a long-duration mission to Mars are examined, focusing on 14 behavioral issues with design implications. Consideration is given to sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy, waste disposal, onboard training, and the microgravity environment. The results are used to develop operational requirements and habitability design guidelines for interplanetary spacecraft.

  13. HIV epidemic among key populations in west Africa.

    PubMed

    Djomand, Gaston; Quaye, Silas; Sullivan, Patrick S

    2014-09-01

    Globally, HIV infection remains a significant issue for key populations such as men who have sex with men (MSM) and female sex workers. A review of recent articles was conducted for west African countries to assess the burden of disease among female sex workers and MSM, access to services and identify barriers to implementation of services for key populations. In west Africa, key populations engage in high-risk practices for the acquisition of HIV and other sexually transmitted infections. Available HIV prevalence data fluctuate across and within countries for both MSM and female sex workers and may be five to ten times as high as that of the general population. HIV prevalence varied from 15.9% in The Gambia to 68% in Benin among female sex workers, whereas it ranged from 9.8% in The Gambia to 34.9% in Nigeria for MSM. Yet, important data gaps exist, including key populations size estimations in several countries as well as HIV prevalence, incidence and other biomarkers of HIV risk. Because of sociocultural, legal, political and economic challenges, exacerbated by a poor health system infrastructure, the HIV response is not strategically directed toward programs for key populations in countries with concentrated epidemics. Noteworthy is the low coverage of prevention care and treatment interventions offered to key populations. Sufficient planning and political will with legal and structural frameworks that reconcile public health and human rights are needed to prioritize HIV prevention, care and treatment programming for key populations programs in west Africa.

  14. Identifying Key Issues and Potential Solutions for Integrated Arrival, Departure, Surface Operations by Surveying Stakeholder Preferences

    NASA Technical Reports Server (NTRS)

    Aponso, Bimal; Coppenbarger, Richard A.; Jung, Yoon; Quon, Leighton; Lohr, Gary; O’Connor, Neil; Engelland, Shawn

    2015-01-01

    NASA's Aeronautics Research Mission Directorate (ARMD) collaborates with the FAA and industry to provide concepts and technologies that enhance the transition to the next-generation air-traffic management system (NextGen). To facilitate this collaboration, ARMD has a series of Airspace Technology Demonstration (ATD) sub-projects that develop, demonstrate, and transitions NASA technologies and concepts for implementation in the National Airspace System (NAS). The second of these sub-projects, ATD-2, is focused on the potential benefits to NAS stakeholders of integrated arrival, departure, surface (IADS) operations. To determine the project objectives and assess the benefits of a potential solution, NASA surveyed NAS stakeholders to understand the existing issues in arrival, departure, and surface operations, and the perceived benefits of better integrating these operations. NASA surveyed a broad cross-section of stakeholders representing the airlines, airports, air-navigation service providers, and industry providers of NAS tools. The survey indicated that improving the predictability of flight times (schedules) could improve efficiency in arrival, departure, and surface operations. Stakeholders also mentioned the need for better strategic and tactical information on traffic constraints as well as better information sharing and a coupled collaborative planning process that allows stakeholders to coordinate IADS operations. To assess the impact of a potential solution, NASA sketched an initial departure scheduling concept and assessed its viability by surveying a select group of stakeholders for a second time. The objective of the departure scheduler was to enable flights to move continuously from gate to cruise with minimal interruption in a busy metroplex airspace environment using strategic and tactical scheduling enhanced by collaborative planning between airlines and service providers. The stakeholders agreed that this departure concept could improve schedule

  15. Invited Commentary on "Issues in Differential Response"

    ERIC Educational Resources Information Center

    Vaughan-Eden, Viola; Vandervort, Frank E.

    2013-01-01

    Ronald Hughes and his colleagues have written a groundbreaking article on child welfare's use of differential response. Their research addresses the matter from a "lessons learned" and "ways to improve" approach. Our comments focused on three key issues: (1) the importance of evidence-based practice; (2) the recognition…

  16. Policy Issues in Gay and Lesbian Adoption.

    ERIC Educational Resources Information Center

    Sullivan, Ann

    1995-01-01

    Notes that adoption agencies have developed few specific policies on the issue of lesbian and gay adoption. Provides an overview of key considerations about homosexual adopters, including beliefs and values of agency professionals, the legal and social ramifications of adoption into a relationship not based on marriage, and possible consequences…

  17. Women and Careers: Issues and Challenges.

    ERIC Educational Resources Information Center

    Konek, Carol Wolfe, Ed.; Kitch, Sally L., Ed.

    This book presents, in 11 chapters, results of a major survey to discover how women feel about the key issues surrounding their experiences in the workplace. The survey, conducted by the Research Group on Women and Work, was sent to 770 women in Wichita, Kansas; it received 494 responses, augmented by 238 responses to a follow-up survey 5 years…

  18. Assessing Campus Climates for Lesbian, Gay, Bisexual and Transgender (LGBT) Students: Methodological and Political Issues

    ERIC Educational Resources Information Center

    Brown, Robert D.; Gortmaker, Valerie J.

    2009-01-01

    Methodological and political issues arise during the designing, conducting, and reporting of campus-climate studies for LGBT students. These issues interact; making a decision about a methodological issue (e.g., sample size) has an impact on a political issue (e.g., how well the findings will be received). Ten key questions that must be addressed…

  19. Key Issue: Enhancing Teacher Leadership

    ERIC Educational Resources Information Center

    National Comprehensive Center for Teacher Quality, 2007

    2007-01-01

    "Teachers are leaders when they function in professional communities to affect student learning; contribute to school improvement; inspire excellence in practice; and empower stakeholders to participate in educational improvement" (Childs-Bowen, Moller, & Scrivner, 2000, p. 28). Enhancing teacher leadership can help schools and districts reach the…

  20. Special Education Law: Illustrative Basics and Nuances of Key IDEA Components

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2015-01-01

    Intended as professional development for both new and experienced special educators, this article provides both the basic requirements and nuanced issues for foundational, successive, and overlapping key components under the Individuals With Disabilities Education Act (IDEA): (a) child find, (b) eligibility, and (c) free appropriate public…

  1. The Development of Resources of Students in Adolescence as a Key Issue in Contemporary Education

    ERIC Educational Resources Information Center

    Gosk, Urszula; Kuracki, Kamil

    2015-01-01

    In the presented paper, the issue of recognition and building of resources in adolescent pupils was discussed, referring to salutogenic concept of A. Antonovsky and Conservation of Resources Theory of S. E. Hobfoll. Coming out from developmental pedagogy and positive orientation in social sciences, benefits of scientific and educational actions…

  2. Model of the Students' Key Competences Development through Interactive Whiteboard in the Subject of Technology

    ERIC Educational Resources Information Center

    Brecka, Peter; Valentová, Monika

    2017-01-01

    The basis of the submitted study are the continuously rising demands to alter the curricula with the aim to develop students' key competences in order to increase their professional versatility. The lack of scientific research and discussions show that little investigation has been done on the issue of development of key competences. Therefore,…

  3. Technical Solutions to Common Indoor Air Quality Issues in Schools

    EPA Pesticide Factsheets

    Indoor Air Quality (IAQ) Design Tools for Schools provides voluntary guidance for school personnel, architects, engineers, builders and contractors, parents, and the community on key school construction and renovation issues.

  4. Issues Emerging from First-Year PDS Implementation.

    ERIC Educational Resources Information Center

    Castle, Sharon; Groth, Lois; Shaklee, Beverly

    This paper focuses on a revised Professional Development School (PDS) program and what participant groups perceived to be key issues during the first year of implementation. It addresses the role of PDSs in improving the quality of beginning teachers within a non-supportive state policy environment. The George Mason University Elementary program…

  5. USSR Space Life Sciences Digest. Index to issues 5-9

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran

    1987-01-01

    An index to issues 5 through 9 of the USSR Space Life Sciences Digest is provided in two sections. The first section lists bibliographic citations of abstracts contained in the Digest issues covered, grouped by topic area categories. Cross references to other relevant abstracts in different categories are also provided. The second section provides a key word index for the same set of abstracts.

  6. Ecotoxicology for risk assessment in arid zones: some key issues.

    PubMed

    Everts, J W

    1997-01-01

    In the hot arid zones of the world, ecotoxicological research is in statu nascendi. In these zones, the major sources of contamination by toxicants are: (1) plant protection and vector control in wet zones; (2) large-scale crop protection campaigns in dry and ephemeral wet zones; (3) refuse and obsolete pesticides in dry zones; and (4) mining. Economic development in many of these zones requires an adequate knowledge of certain basic principles, i.e., where extrapolating existing knowledge does not apply. The vulnerability of ecosystems to contaminants is closely related to water flow. In dry areas, species are susceptible to factors that interfere with the ecophysiological properties regulating water loss. Most hot arid areas are found at low latitudes where temperatures show striking extremes both in time and space. Living organisms are physiologically resistant and/or show adaptive behavior to these temperature extremes. Very little is known about the effects of toxicants on these key resistant and adaptive functions, although by extrapolation a few assumptions can be made. The effects of hyperthermia, for instance, can be aggravated by GSH depleting substances, and the temporary disabling effects characteristic of many pesticides may prove fatal under these circumstances. Most wet areas show a spatial concentration of both human activity and wildlife. In mesic zones, the contamination of water represents a health risk to both humans and other living organisms. The vast majority of aquatic communities are those inhabiting temporary pools and streams. Their populations are characterized by short reproductive cycles and/or long dormant stages. Toxicants affecting growth in these areas have been shown to have a deleterious effect. In a synthesis of existing knowledge the most prominent gaps are identified and priorities for further research are made.

  7. Key Data Gaps Regarding the Public Health Issues Associated with Opioid Analgesics

    PubMed Central

    Schmidt, Teresa D.; Haddox, J. David; Nielsen, Alexandra E.; Wakeland, Wayne; Fitzgerald, John

    2014-01-01

    Most pharmaceutical opioids are used to treat pain and they have been demonstrated to be effective medications for many. Their abuse and misuse pose significant public health concerns in the United States. Research has provided much insight into the prevalence, scope, and drivers of opioid abuse, but a holistic understanding is limited by a lack of available data regarding key aspects of this public health problem. Twelve data gaps were revealed during the creation of a systems-level computer model of medical use, diversion, nonmedical use, and the adverse outcomes associated with opioid analgesics in the United States. Data specific to these gaps would enhance the validity and real-world applications of systems-level models of this public health problem, and would increase understanding of the complex system in which use and abuse occur. This paper provides an overview of these gaps, argues for the importance of closing them, and provides specific recommendations for future data collection efforts. PMID:24554390

  8. The Children's Inn at NIH Anniversary Key Messages | NIH MedlinePlus the Magazine

    MedlinePlus

    ... Past Issues / Summer 2014 Table of Contents Anniversary Key Messages Playground and Park at The Children's Inn ... and commitment, and the merging of public and private resources. Merck generously donated $3.7 million for ...

  9. Decontamination, decommissioning, and vendor advertorial issue, 2005

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

    Agnihotri, Newal

    2005-07-15

    The focus of the July-August issue is on Decontamination, decommissioning, and vendor advertorials. Major interviews, articles and reports in this issue include: Increasing momentum, by Gary Taylor, Entergy Nuclear, Inc.; An acceptable investment, by Tom Chrisopher, Areva, Inc.; Fuel recycling for the U.S. and abroad, by Philippe Knoche, Areva, France; We're bullish on nuclear power, by Dan R. Keuter, Entergy Nuclear, Inc.; Ten key actions for decommissioning, by Lawrence E. Boing, Argonne National Laboratory; Safe, efficient and cost-effective decommissioning, by Dr. Claudio Pescatore and Torsten Eng, OECD Nuclear Energy Agency (NEA), France; and, Plant profile: SONGS decommissioning.

  10. Overview of Variable Renewable Energy Regulatory Issues: A Clean Energy Regulators Initiative Report

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

    Miller, M.; Cox, S.

    This CERI report aims to provide an introductory overview of key regulatory issues associated with the deployment of renewable energy -- particularly variable renewable energy (VRE) sources such wind and solar power. The report draws upon the research and experiences from various international contexts, and identifies key ideas that have emerged from the growing body of VRE deployment experience and regulatory knowledge. The report assumes basic familiarity with regulatory concepts, and although it is not written for a technical audience, directs the reader to further reading when available. VRE deployment generates various regulatory issues: substantive, procedural, and public interest issues,more » and the report aims to provide an empirical and technical grounding for all three types of questions as appropriate.« less

  11. Can Competency-Based Training Fly?: An Overview of Key Issues for "Ab Initio" Pilot Training

    ERIC Educational Resources Information Center

    Franks, Peter; Hay, Stephen; Mavin, Tim

    2014-01-01

    Competency-based training (CBT) for pilots was formally introduced in 1999 by the Civil Aviation Safety Authority (CASA) for training leading to the issue of aeroplane private and commercial pilot licences. This initiative followed the Australian government's introduction of CBT policy for vocational and workplace training in the late 1980's.…

  12. Key-value store with internal key-value storage interface

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

    Bent, John M.; Faibish, Sorin; Ting, Dennis P. J.

    A key-value store is provided having one or more key-value storage interfaces. A key-value store on at least one compute node comprises a memory for storing a plurality of key-value pairs; and an abstract storage interface comprising a software interface module that communicates with at least one persistent storage device providing a key-value interface for persistent storage of one or more of the plurality of key-value pairs, wherein the software interface module provides the one or more key-value pairs to the at least one persistent storage device in a key-value format. The abstract storage interface optionally processes one or moremore » batch operations on the plurality of key-value pairs. A distributed embodiment for a partitioned key-value store is also provided.« less

  13. Research on the architecture and key technologies of SIG

    NASA Astrophysics Data System (ADS)

    Fu, Zhongliang; Meng, Qingxiang; Huang, Yan; Liu, Shufan

    2007-06-01

    Along with the development of computer network, Grid has become one of the hottest issues of researches on sharing and cooperation of Internet resources throughout the world. This paper illustrates a new architecture of SIG-a five-hierarchy architecture (including Data Collecting Layer, Grid Layer, Service Layer, Application Layer and Client Layer) of SIG from the traditional three hierarchies (only including resource layer, service layer and client layer). In the paper, the author proposes a new mixed network mode of Spatial Information Grid which integrates CAG (Certificate Authority of Grid) and P2P (Peer to Peer) in the Grid Layer, besides, the author discusses some key technologies of SIG and analysis the functions of these key technologies.

  14. Public engagement with CCS: barriers, key issues and ways forward

    NASA Astrophysics Data System (ADS)

    Xenias, Dimitrios

    2017-04-01

    Although Carbon Capture and Storage (CCS) is recognised as a crucial transition technology to a low-carbon world, it has not been popular with the public or some governments (e.g. the UK). Also, despite its use in industrial processes for decades, CCS remains and unfamiliar technology for most publics. It is therefore important to foster top-down and bottom-up acceptance of large scale CCS. In an exploratory round of interviews we canvassed the views of British, Dutch, German and Norwegian experts (N=13) with previous experience in public engagement with CCS. They identified barriers and drivers for CCS deployment and public engagement with CCS. Thematic analysis revealed a small number of recurrent issues, including: (a) lack of political leadership on CCS; (b) lack of public knowledge on relevant technologies and (c) difficulty communicating why CCS is necessary. Emphasis on these barriers varied with the level of experts' engagement with the public. More interestingly, although most experts agreed on the importance of public engagement, their views divided between 'why' engage and 'how' best to do this. In a subsequent expert survey (N=99) interview findings were reinforced: public support was seen as important for CCS roll-out (72%), though lower than political support and funding. The survey also showed that local public was expected to experience most risks, while global public will experience most benefits; whereas local business is seen to benefit more than global. Experts were overwhelmingly positive about CCS - risks outweigh benefits, and are confident that CCS will play a major role in climate change mitigation (along with reduced energy demand and renewables). These findings will be expanded on and triangulated in a follow-up public survey which will benefit those involved with public engagement with CCS.

  15. GAIA - A New Approach To Decision Making on Climate Disruption Issues

    NASA Astrophysics Data System (ADS)

    Paxton, L. J.; Weiss, M.; Schaefer, R. K.; Swartz, W. H.; Nix, M.; Strong, S. B.; Fountain, G. H.; Babin, S. M.; Pikas, C. K.; Parker, C. L.; Global Assimilation of InformationAction

    2011-12-01

    GAIA - the Global Assimilation of Information for Action program - provides a broadly extensible framework for enabling the development of a deeper understanding of the issues associated with climate disruption. The key notion of GAIA is that the global climate problem is so complex that a "system engineering" approach is needed in order to make it understandable. The key tenet of system engineering is to focus on requirements and to develop a cost-effective process for satisfying those requirements. To demonstrate this approach we focused first on the impact of climate disruption on public health. GAIA is described in some detail on our website (http://gaia.jhuapl.edu). Climate disruption is not just a scientific problem; one of the key issues that our community has is that of translating scientific results into knowledge that can be used to make informed decisions. In order to support decision makers we have to understand their issues and how to communicate with them. In this talk, we describe how we have built a community of interest that combines subject matter experts from diverse communities (public health, climate change, government, public policy, industry, etc) with policy makers and representatives from industry to develop, on a "level playing field", an understanding of each other's points of view and issues. The first application of this technology was the development of a workshop on Climate, Climate Change and Public Health held April 12-14, 2011. This paper describes our approach to going beyond the workshop environment to continue to engage the decision maker's community in a variety of ways that translate abstract scientific data into actionable information. Key ideas we will discuss include the development of social media, simulations of global/national/local environments affected by climate disruption, and visualizations of the monetary and health impacts of choosing not to address mitigation or adaptation to climate disruption.

  16. Coupled Model for CO2 Leaks from Geological Storage: Geomechanics, Fluid Flow and Phase Transitions

    NASA Astrophysics Data System (ADS)

    Gor, G.; Prevost, J.

    2013-12-01

    Deep saline aquifers are considered as a promising option for long-term storage of carbon dioxide. However, risk of CO2 leakage from the aquifers through faults, natural or induced fractures or abandoned wells cannot be disregarded. Therefore, modeling of various leakage scenarios is crucial when selecting a site for CO2 sequestration and choosing proper operational conditions. Carbon dioxide is injected into wells at supercritical conditions (t > 31.04 C, P > 73.82 bar), and these conditions are maintained in the deep aquifers (at 1-2 km depth) due to hydrostatic pressure and geothermal gradient. However, if CO2 and brine start to migrate from the aquifer upward, both pressure and temperature will decrease, and at the depth of 500-750 m, the conditions for CO2 will become subcritical. At subcritical conditions, CO2 starts boiling and the character of the flow changes dramatically due to appearance of the third (vapor) phase and latent heat effects. When modeling CO2 leaks, one needs to couple the multiphase flow in porous media with geomechanics. These capabilities are provided by Dynaflow, a finite element analysis program [1]; Dynaflow has already showed to be efficient for modeling caprock failure causing CO2 leaks [2, 3]. Currently we have extended the capabilities of Dynaflow with the phase transition module, based on two-phase and three-phase isenthalpic flash calculations [4]. We have also developed and implemented an efficient method for solving heat and mass transport with the phase transition using our flash module. Therefore, we have developed a robust tool for modeling CO2 leaks. In the talk we will give a brief overview of our method and illustrate it with the results of simulations for characteristic test cases. References: [1] J.H. Prevost, DYNAFLOW: A Nonlinear Transient Finite Element Analysis Program. Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ. http://www.princeton.edu/~dynaflow/ (last update 2013

  17. Multiscale Simulation Framework for Coupled Fluid Flow and Mechanical Deformation

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

    Hou, Thomas; Efendiev, Yalchin; Tchelepi, Hamdi

    2016-05-24

    Our work in this project is aimed at making fundamental advances in multiscale methods for flow and transport in highly heterogeneous porous media. The main thrust of this research is to develop a systematic multiscale analysis and efficient coarse-scale models that can capture global effects and extend existing multiscale approaches to problems with additional physics and uncertainties. A key emphasis is on problems without an apparent scale separation. Multiscale solution methods are currently under active investigation for the simulation of subsurface flow in heterogeneous formations. These procedures capture the effects of fine-scale permeability variations through the calculation of specialized coarse-scalemore » basis functions. Most of the multiscale techniques presented to date employ localization approximations in the calculation of these basis functions. For some highly correlated (e.g., channelized) formations, however, global effects are important and these may need to be incorporated into the multiscale basis functions. Other challenging issues facing multiscale simulations are the extension of existing multiscale techniques to problems with additional physics, such as compressibility, capillary effects, etc. In our project, we explore the improvement of multiscale methods through the incorporation of additional (single-phase flow) information and the development of a general multiscale framework for flows in the presence of uncertainties, compressible flow and heterogeneous transport, and geomechanics. We have considered (1) adaptive local-global multiscale methods, (2) multiscale methods for the transport equation, (3) operator-based multiscale methods and solvers, (4) multiscale methods in the presence of uncertainties and applications, (5) multiscale finite element methods for high contrast porous media and their generalizations, and (6) multiscale methods for geomechanics.« less

  18. Chronic Absenteeism: A Key Indicator of Student Success. Policy Analysis

    ERIC Educational Resources Information Center

    Rafa, Alyssa

    2017-01-01

    Research shows that chronic absenteeism can affect academic performance in later grades and is a key early warning sign that a student is more likely to drop out of high school. Several states enacted legislation to address this issue, and many states are currently discussing the utility of chronic absenteeism as an indicator of school quality or…

  19. Introduction strategies raise key questions.

    PubMed

    Finger, W R; Keller, S

    1995-09-01

    Key issues that must be considered before a new contraceptive is introduced center on the need for a trained provider to begin or terminate the method, its side effects, duration of use, method's ability to meet users' needs and preferences, and extra training or staff requirements. Logistics and economic issues to consider are identifying a dependable way of effectively supplying commodities, planning extra services needed for the method, and cost of providing the method. Each contraceptive method presents a different side effect pattern and burdens the service delivery setting differently. The strategy developed to introduce or expand the 3-month injectable Depo-Provera (DMPA) can be used for any method. It includes a needs assessment and addresses regulatory issues, service delivery policies and procedures, information and training, evaluation, and other concerns. Viet Nam's needs assessment showed that Norplant should not be introduced until the service delivery system becomes stronger. Any needs assessment for expansion of contraceptive services should cover sexually transmitted disease/HIV issues. A World Health Organization strategy helps officials identify the best method mix for local situations. Introductory strategies must aim to improve the quality of family planning programs and expand choices. Many begin by examining existing data and conducting interviews with policymakers, users, providers, and women's health advocates. Introductory programs for Norplant focus on provider training, adequate counseling and informed consent for users, and ready access to removal. They need a well-prepared service delivery infrastructure. The first phase of the DMPA introductory strategy for the Philippines comprised a social marketing campaign and DMPA introduction at public clinics in 10 pilot areas with strong service delivery. Successful AIDS prevention programs show that people tend to use barrier methods when they are available. USAID is currently studying

  20. The role of gender in the socialization of emotion: key concepts and critical issues.

    PubMed

    Root, Amy Kennedy; Denham, Susanne A

    2010-01-01

    Given the omnipresent role of gender in children's and adolescents' development, it seems necessary to better understand how gender affects the process of emotion socialization. In this introductory chapter, the authors discuss the overarching themes and key concepts discussed in this volume, as well as outline the distinct contribution of each individual chapter. Each chapter within this volume underscores the important role that parents play in the socialization of emotion, and the impact gender-typed emotion socialization may have on later socioemotional adjustment. (c) Wiley Periodicals, Inc.

  1. Labor force planning issues for allied health in Australia.

    PubMed

    Smith, C S; Crowley, S

    1995-01-01

    The aim of this paper is to discuss labor force planning issues for allied health professionals in Australia. Health system reform and changes in the demand for health labor, combined with key characteristics of the professions, will have a profound influence on future needs for career development of allied health professionals. Key issues include the increasing need for allied health professionals to undertake business management and public health training, the growing trend of multiskilling versus specialization, and the need for the professions to diversify their skill base to ensure a range of career options in a changing health care system. The challenge for allied health professions is to improve tools of analysis in relation to labor force planning and to systematically investigate various factors influencing labor force supply and demand, on both a short-term and long-term basis.

  2. The Student Issue. Original Articles by Student Gammans.

    ERIC Educational Resources Information Center

    Neill, Kweethai C., Ed.

    1997-01-01

    This issue contains eight articles on health education by student members of Eta Sigma Gamma, the National Professional Health Education Honorary. The papers are: (1) "Community Involvement: The Key to Successful Implementation of Comprehensive School Health Education" (Crystal L. Bieterman); (2) "HIV Infection and the Hispanic…

  3. A Round-Efficient Authenticated Key Agreement Scheme Based on Extended Chaotic Maps for Group Cloud Meeting.

    PubMed

    Lin, Tsung-Hung; Tsung, Chen-Kun; Lee, Tian-Fu; Wang, Zeng-Bo

    2017-12-03

    The security is a critical issue for business purposes. For example, the cloud meeting must consider strong security to maintain the communication privacy. Considering the scenario with cloud meeting, we apply extended chaotic map to present passwordless group authentication key agreement, termed as Passwordless Group Authentication Key Agreement (PL-GAKA). PL-GAKA improves the computation efficiency for the simple group password-based authenticated key agreement (SGPAKE) proposed by Lee et al. in terms of computing the session key. Since the extended chaotic map has equivalent security level to the Diffie-Hellman key exchange scheme applied by SGPAKE, the security of PL-GAKA is not sacrificed when improving the computation efficiency. Moreover, PL-GAKA is a passwordless scheme, so the password maintenance is not necessary. Short-term authentication is considered, hence the communication security is stronger than other protocols by dynamically generating session key in each cloud meeting. In our analysis, we first prove that each meeting member can get the correct information during the meeting. We analyze common security issues for the proposed PL-GAKA in terms of session key security, mutual authentication, perfect forward security, and data integrity. Moreover, we also demonstrate that communicating in PL-GAKA is secure when suffering replay attacks, impersonation attacks, privileged insider attacks, and stolen-verifier attacks. Eventually, an overall comparison is given to show the performance between PL-GAKA, SGPAKE and related solutions.

  4. A guide to Social Security money's worth issues.

    PubMed

    Leimer, D R

    1995-01-01

    This article discusses some of the major issues associated with the question of whether workers receive their money's worth from the Social Security program. An effort is made to keep the discussion as nontechnical as possible, with explanations provided for many of the technical terms and concepts found in the money's worth literature. Major assumptions, key analytical methods, and money's worth measures used in the literature are also discussed. Finally, the key findings of money's worth studies are summarized, with some cautions concerning the limitations and appropriate usage of money's worth analyses.

  5. Florida Keys

    NASA Image and Video Library

    2002-12-13

    The Florida Keys are a chain of islands, islets and reefs extending from Virginia Key to the Dry Tortugas for about 309 kilometers (192 miles). The keys are chiefly limestone and coral formations. The larger islands of the group are Key West (with its airport), Key Largo, Sugarloaf Key, and Boca Chica Key. A causeway extends from the mainland to Key West. This image was acquired on October 28, 2001, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA03890

  6. Key challenges in the development and implementation of telehealth projects.

    PubMed

    Joseph, Victor; West, Robert M; Shickle, Darren; Keen, Justin; Clamp, Susan

    2011-01-01

    A literature review was carried out to identify the key challenges in the implementation of telehealth. This was followed by a survey of organisations in England involved in telehealth projects in order to understand the challenges they faced. Ten of the 13 health or local authority organisations surveyed had telehealth projects and three were at the planning stage. The analysis revealed seven key challenges facing implementers of telehealth in England. Based on the findings from the literature review and the survey, a model was constructed and a checklist drawn up. The model contained the following elements: identifying issues, needs and partners; producing a strategy; securing funding; implementing changes; and monitoring and evaluating a telehealth project. The checklist was validated by using key informants from the organisations originally surveyed. The checklist may be useful to guide telehealth development and implementation in the future.

  7. Key Technologies of Phone Storage Forensics Based on ARM Architecture

    NASA Astrophysics Data System (ADS)

    Zhang, Jianghan; Che, Shengbing

    2018-03-01

    Smart phones are mainly running Android, IOS and Windows Phone three mobile platform operating systems. The android smart phone has the best market shares and its processor chips are almost ARM software architecture. The chips memory address mapping mechanism of ARM software architecture is different with x86 software architecture. To forensics to android mart phone, we need to understand three key technologies: memory data acquisition, the conversion mechanism from virtual address to the physical address, and find the system’s key data. This article presents a viable solution which does not rely on the operating system API for a complete solution to these three issues.

  8. Issues Involved in the Evaluation of Gifted Programmes.

    ERIC Educational Resources Information Center

    Ali, A. Sidiq

    2001-01-01

    This article discusses the purpose of gifted program evaluation and identifies some of the pertinent issues involved in evaluating gifted programs. The gifted program delivered by the Peel District Board of Education in Ontario, Canada, is used to illustrate key evaluation considerations, including gifted identification procedures and gifted…

  9. "Let Me Keep My Dead Husband's Sperm": Ethical Issues in Posthumous Reproduction.

    PubMed

    Panagiotopoulou, Nikoletta; Karavolos, Stamatios

    2015-01-01

    The feasibility of posthumous reproduction when the surviving partner is female has brought to light many ethical, moral, social, and legal issues. This review aims to summarize these issues and to assist clinicians who may be faced with such requests. A question list, used for health technologies assessment, was utilized in a question-answer approach as the review methodology. Of the 1,208 publications identified through a comprehensive literature search in biomedical, psychological, and ethical databases, 31 articles included arguments related to one or more questions from the predefined question set. Key stakeholders identified include the deceased, the requesting party, the resultant child, the physician, and society. Key ethical issues relevant to posthumous reproduction include the four traditional pillars of medical ethics--autonomy, beneficence, nonmaleficence, justice--as well as the stakeholders' rights and sociocultural attitudes. The ethical framework formulated by these issues has been incorporated in a clinical ethics decision-making tool that could prove useful to clinicians and decision makers. Copyright 2015 The Journal of Clinical Ethics. All rights reserved.

  10. Implementation Issues for Departure Planning Systems

    NASA Technical Reports Server (NTRS)

    Hansman, R. John; Feron, Eric; Clarke, John-Paul; Odoni, Amedeo

    1999-01-01

    The objective of the proposed effort is to investigate issues associated with the design and implementation of decision aiding tools to assist in improving the departure process at congested airports. This effort follows a preliminary investigation of potential Departure Planning approaches and strategies, which identified potential benefits in departure efficiency, and also in reducing the environmental impact of aircraft in the departure queue. The preliminary study bas based, in large part, on observations and analysis of departure processes at Boston, Logan airport. The objective of this follow-on effort is to address key implementation issues and to expand the observational base to include airports with different constraints and traffic demand. Specifically, the objectives of this research are to: (1) Expand the observational base to include airports with different underlying operational dynamics. (2) Develop prototype decision aiding algorithms/approaches and assess potential benefits. and (3) Investigate Human Machine Integration (HMI) issues associated with decision aids in tower environments.

  11. Extrinsic and Intrinsic Motivation at 30: Unresolved Scientific Issues

    ERIC Educational Resources Information Center

    Reiss, Steven

    2005-01-01

    The undermining effect of extrinsic reward on intrinsic motivation remains unproven. The key unresolved issues are construct invalidity (all four definitions are unproved and two are illogical); measurement unreliability (the free-choice measure requires unreliable, subjective judgments to infer intrinsic motivation); inadequate experimental…

  12. The international scale of the groundwater issue

    USGS Publications Warehouse

    Fienen, Michael; Arshad, Muhammad

    2016-01-01

    Throughout history, and throughout the world, groundwater has been a major source of water for sustaining human life. Use of this resource has increased dramatically over the last century. In many areas of the world, the balance between human and ecosystem needs is difficult to maintain. Understanding the international scale of the groundwater issue requires metrics and analysis at a commensurate scale. Advances in remote sensing supplement older traditional direct measurement methods for understanding the magnitude of depletion, and all measurements motivate the need for common data standards to collect and share information. In addition to metrics of groundwater availability, four key international groundwater issues are depletion of water, degradation of water quality, the water-energy nexus, and transboundary water conflicts. This chapter is devoted to introducing these issues, which are also discussed in more detail in later chapters.

  13. Legal Issues for Postsecondary Education. Briefing Papers 1.

    ERIC Educational Resources Information Center

    Blumer, Dennis H., Ed.

    This publication is intended to outline basic legal issues in key areas confronting the postsecondary education community, and to provide background information of which every college administrator should be aware. Chapter 1, Some General Thoughts on Postsecondary Education and the Law, discusses the increased activity of courts in campus matters…

  14. The Online Catalog: Issues in Planning and Development.

    ERIC Educational Resources Information Center

    Richards, Timothy F.

    1984-01-01

    Discusses key issues to be addressed in planning for introduction of online public access catalog in academic research library environment. Purpose of catalog, reasons to adopt catalog, user behavior, use of catalog records, authority control, shared or unique systems, and impact on staff are highlighted. Seventy-three sources are cited. (EJS)

  15. USSR Space Life Sciences Digest. Index to issues 15-20

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor)

    1989-01-01

    This bibliography provides an index to issues 15 through 20 of the USSR Space Life Sciences Digest. There are two sections. The first section lists bibliographic citations of abstracts in these issues, grouped by topic area categories. The second section provides a key word index for the same abstracts. The topic categories include exobiology, space medicine and psychology, human performance and man-machine systems, various life/body systems, human behavior and adaptation, biospherics, and others.

  16. USSR Space Life Sciences Digest. Index to issues 21-25

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor)

    1990-01-01

    This bibliography provides an index to issues 21 through 25 of the USSR Space Life Sciences Digest. There are two sections. The first section lists bibliographic citations of abstracts in these issues, grouped by topic area categories. The second section provides a key word index for the same abstracts. The topic categories include exobiology, space medicine and psychology, human performance and man-machine systems, various life/body systems, human behavior and adaptation, biospherics, and others.

  17. USSR Space Life Sciences Digest. Index to issues 26-29

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor)

    1991-01-01

    This bibliography provides an index to issues 26 through 29 of the USSR Space Life Sciences Digest. There are two sections. The first section lists bibliographic citations of abstracts in these issues, grouped by topic area categories. The second section provides a key word index for the same abstracts. The topic categories include exobiology, space medicine and psychology, human performance and man-machine systems, various life/body systems, human behavior and adaptation, biospherics, and others.

  18. Function key and shortcut key use in airway facilities.

    DOT National Transportation Integrated Search

    2003-02-01

    This document provides information on the function keys and shortcut keys used by systems in the Federal Aviation Administration : Airway Facilities (AF) work environment. It includes a catalog of the function keys and shortcut keys used by each syst...

  19. Independent assessment is key to financial well-being.

    PubMed

    Karling, J; Pyper, T

    1999-02-01

    Both traditional group practices and IPAs have felt the impact of changes brought about by managed care. Group practices need to ensure that their financial reporting and cost-accounting methods capture information that is key to decision making. An independent assessment of financial procedures helps identify any outstanding issues and maintain financial well-being. This assessment should be conducted at least quarterly so that potential problems can be resolved, income opportunities explored, and cost-saving measures adopted in a timely manner.

  20. Emerging issues in biodiversity & conservation management: The need for a palaeoecological perspective

    NASA Astrophysics Data System (ADS)

    Froyd, C. A.; Willis, K. J.

    2008-09-01

    The study of Quaternary environmental change is directly applicable to on-going issues of global conservation. Palaeoecological research techniques provide the tools to address some of the key questions presently being asked by conservation ecologists and land management organizations. But is this type of analysis currently being utilized to its full potential? Are the results of palaeoenvironmental analyses routinely applied to practical issues of natural resource management, and if not what can be done to expand the application of this research within the conservation community? This paper reviews recent developments in the application of the analysis of late Quaternary environmental change to key environmental issues of biodiversity and conservation management and examines areas which could be strengthened in the future including: (i) determination of baselines and natural ecosystem variability; (ii) understanding ecological thresholds and resilience; (iii) climate change conservation strategies; (iv) biological invasions; and (v) conservation and culture.

  1. Rising food costs & global food security: key issues & relevance for India.

    PubMed

    Gustafson, Daniel J

    2013-09-01

    Rising food costs can have major impact on vulnerable households, pushing those least able to cope further into poverty and hunger. On the other hand, provided appropriate policies and infrastructure are in place, higher agricultural prices can also raise farmers' incomes and rural wages, improve rural economies and stimulate investment for longer-term economic growth. High food prices since 2007 have had both short-term impacts and long-term consequences, both good and bad. This article reviews the evidence of how rising costs have affected global food security since the food price crisis of 2007-2008, and their impact on different categories of households and countries. In light of recent studies, we know more about how households, and countries, cope or not with food price shocks but a number of contentious issues remain. These include the adequacy of current estimates and the interpretation of national and household food and nutrition security indicators. India is a particularly important country in this regard, given the high number of food insecure, the relative weight of India in global estimates of food and nutrition insecurity, and the puzzles that remain concerning the country's reported declining per capita calorie consumption. Competing explanations for what is behind it are not in agreement, but these all point to the importance of policy and programme innovation and greater investment necessary to reach the achievable goal of food and nutrition security for all.

  2. Rising food costs & global food security: Key issues & relevance for India

    PubMed Central

    Gustafson, Daniel J.

    2013-01-01

    Rising food costs can have major impact on vulnerable households, pushing those least able to cope further into poverty and hunger. On the other hand, provided appropriate policies and infrastructure are in place, higher agricultural prices can also raise farmers’ incomes and rural wages, improve rural economies and stimulate investment for longer-term economic growth. High food prices since 2007 have had both short-term impacts and long-term consequences, both good and bad. This article reviews the evidence of how rising costs have affected global food security since the food price crisis of 2007-2008, and their impact on different categories of households and countries. In light of recent studies, we know more about how households, and countries, cope or not with food price shocks but a number of contentious issues remain. These include the adequacy of current estimates and the interpretation of national and household food and nutrition security indicators. India is a particularly important country in this regard, given the high number of food insecure, the relative weight of India in global estimates of food and nutrition insecurity, and the puzzles that remain concerning the country's reported declining per capita calorie consumption. Competing explanations for what is behind it are not in agreement, but these all point to the importance of policy and programme innovation and greater investment necessary to reach the achievable goal of food and nutrition security for all. PMID:24135190

  3. The Text's the Thing: Using (Neglected) Issues of Textual Scholarship to Help Students Reimagine Shakespeare

    ERIC Educational Resources Information Center

    Parsons, Scott

    2009-01-01

    Do individuals know what words Shakespeare actually wrote? Exploring these issues can yield dramatic interest. With references to Shakespeare's Quartos and Folios, the author examines key textual issues and discrepancies in classroom studies of "Hamlet." (Contains 8 notes.)

  4. Pretest 3-D finite element modeling of the wedge pillar portion of the WIPP (Waste Isolation Pilot Plant) Geomechanical Evaluation (Room G) in situ experiment. [Waste Isolation Pilot Plant

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

    Preece, D.S.

    Pretest 3-D finite element calculations have been performed on the wedge pillar portion of the WIPP Geomechanical Evaluation Experiment. The wedge pillar separates two drifts that intersect at an angle of 7.5/sup 0/. Purpose of the experiment is to provide data on the creep behavior of the wedge and progressive failure at the tip. The first set of calculations utilized a symmetry plane on the center-line of the wedge which allowed treatment of the entire configuration by modeling half of the geometry. Two 3-D calculations in this first set were performed with different drift widths to study the influence ofmore » drift size on closure and maximum stress. A cross-section perpendicular to the wedge was also analyzed with 2-D finite element models and the results compared to the 3-D results. In another set of 3-D calculations both drifts were modeled but with less distance between the drifts and the outer boundaries. Results of these calculations are compared with results from the other calculations to better understand the influence of boundary conditions.« less

  5. A Round-Efficient Authenticated Key Agreement Scheme Based on Extended Chaotic Maps for Group Cloud Meeting

    PubMed Central

    Lee, Tian-Fu; Wang, Zeng-Bo

    2017-01-01

    The security is a critical issue for business purposes. For example, the cloud meeting must consider strong security to maintain the communication privacy. Considering the scenario with cloud meeting, we apply extended chaotic map to present passwordless group authentication key agreement, termed as Passwordless Group Authentication Key Agreement (PL-GAKA). PL-GAKA improves the computation efficiency for the simple group password-based authenticated key agreement (SGPAKE) proposed by Lee et al. in terms of computing the session key. Since the extended chaotic map has equivalent security level to the Diffie–Hellman key exchange scheme applied by SGPAKE, the security of PL-GAKA is not sacrificed when improving the computation efficiency. Moreover, PL-GAKA is a passwordless scheme, so the password maintenance is not necessary. Short-term authentication is considered, hence the communication security is stronger than other protocols by dynamically generating session key in each cloud meeting. In our analysis, we first prove that each meeting member can get the correct information during the meeting. We analyze common security issues for the proposed PL-GAKA in terms of session key security, mutual authentication, perfect forward security, and data integrity. Moreover, we also demonstrate that communicating in PL-GAKA is secure when suffering replay attacks, impersonation attacks, privileged insider attacks, and stolen-verifier attacks. Eventually, an overall comparison is given to show the performance between PL-GAKA, SGPAKE and related solutions. PMID:29207509

  6. Emergent Issues in Enterprise Education: The Educator's Perspective

    ERIC Educational Resources Information Center

    Carey, Charlotte; Matlay, Harry

    2011-01-01

    Recent research suggests that important issues are emerging among enterprise educators in higher education institutions (HEIs). This paper examines four key areas of debate. The first of these is the assessment of entrepreneurship ideas and related activities (Pittaway and Cope, 2007). Penaluna and Penaluna (2008, 2009a, b), for example, focus on…

  7. Increased Attention to Human Sexuality Can Improve HIV-AIDS Prevention Efforts: Key Research Issues and Directions.

    ERIC Educational Resources Information Center

    Kelly, Jeffrey A.; Kalichman, Seth C.

    1995-01-01

    Discusses curtailing the human immunodeficiency virus (HIV) by helping people reduce high-risk sexual behavior. Reviews research in the relationship contexts of sexuality, including variations in monogamy, condom use in affectionate versus casual relationships, sexual communication, and coercion. Notes policy and training issues related to human…

  8. A Case Study of Issues of Strategy Implementation in Internationalization of Higher Education

    ERIC Educational Resources Information Center

    Jiang, Nan; Carpenter, Victoria

    2013-01-01

    Purpose: The purpose of this research is to identify and critically evaluate key issues faced by an institution in the quest to implement higher education internationalization. Design/methodology/approach: A qualitative research is conducted in a post-1992 UK university. A total of 20 interviewees from three key departments participated in this…

  9. DOT's Budget: Safety, Management, and Other Issues Facing the Department in Fiscal Year 1998 and Beyond

    DOT National Transportation Integrated Search

    1997-03-06

    This testimony discusses key resource management issues and performance challenges facing the Department of Transportation in 1998 and beyond. 1. Increased safety and security concerns prompted by accidents and maintenance issues. 2. Important manage...

  10. Defining and Measuring Engagement and Learning in Science: Conceptual, Theoretical, Methodological, and Analytical Issues

    ERIC Educational Resources Information Center

    Azevedo, Roger

    2015-01-01

    Engagement is one of the most widely misused and overgeneralized constructs found in the educational, learning, instructional, and psychological sciences. The articles in this special issue represent a wide range of traditions and highlight several key conceptual, theoretical, methodological, and analytical issues related to defining and measuring…

  11. Simple Web-based interactive key development software (WEBiKEY) and an example key for Kuruna (Poaceae: Bambusoideae).

    PubMed

    Attigala, Lakshmi; De Silva, Nuwan I; Clark, Lynn G

    2016-04-01

    Programs that are user-friendly and freely available for developing Web-based interactive keys are scarce and most of the well-structured applications are relatively expensive. WEBiKEY was developed to enable researchers to easily develop their own Web-based interactive keys with fewer resources. A Web-based multiaccess identification tool (WEBiKEY) was developed that uses freely available Microsoft ASP.NET technologies and an SQL Server database for Windows-based hosting environments. WEBiKEY was tested for its usability with a sample data set, the temperate woody bamboo genus Kuruna (Poaceae). WEBiKEY is freely available to the public and can be used to develop Web-based interactive keys for any group of species. The interactive key we developed for Kuruna using WEBiKEY enables users to visually inspect characteristics of Kuruna and identify an unknown specimen as one of seven possible species in the genus.

  12. Finding the Key to a Good Theatre Program: Some Comments on the ETA Survey.

    ERIC Educational Resources Information Center

    Hobgood, Burnet M.

    1991-01-01

    Offers some comments on the Educational Theatre Association's survey on the status of theater in U.S. high schools in the same issue of this journal. Discusses finding the key factors responsible for good school theater. (PRA)

  13. Locally acquired Dengue--Key West, Florida, 2009-2010.

    PubMed

    2010-05-21

    Dengue is the most common vector-borne viral disease in the world, causing an estimated 50-100 million infections and 25,000 deaths each year. During 1946-1980, no cases of dengue acquired in the continental United States were reported. Since 1980, a few locally acquired U.S. cases have been confirmed along the Texas-Mexico border, temporally associated with large outbreaks in neighboring Mexican cities. On September 1, 2009, a New York physician notified the Monroe County (Florida) Health Department (MCHD) and the Florida Department of Health (FDOH) of a suspected dengue case in a New York state resident whose only recent travel was to Key West, Florida. CDC confirmed the diagnosis, and a press release was issued to notify the public and Key West physicians of the potential risk for locally acquired dengue infections. In the next 2 weeks, two dengue infections in Key West residents without recent travel were reported and confirmed. Subsequently, enhanced and active surveillance identified 24 more Key West cases during 2009. On April 13, 2010, another Key West dengue case was reported to FDOH, bringing the total to 28. This report describes the first three dengue cases reported in 2009, briefly summarizes the 2010 case, highlights preliminary findings from the ongoing investigation, and outlines measures used to mitigate and control the outbreak. Clinicians should include dengue in the differential diagnosis of acute febrile illnesses in patients who live in or have recently traveled to subtropical areas of the United States or to the tropics.

  14. Quality Counts 2008: Tapping into Teaching--Unlocking the Key to Student Success

    ERIC Educational Resources Information Center

    Education Week, 2008

    2008-01-01

    "Quality Counts 2008" reintroduces state grades in six key areas, from the Chance-for-Success Index to the teaching profession. This special issue of "Education Week" includes the following articles: (1) Human Resources a Weak Spot (Lynn Olson); (2) Teacher Salaries, Looking at Comparable Jobs (Christopher B. Swanson); (3) Data…

  15. Special issue on asteroids - Introduction

    NASA Astrophysics Data System (ADS)

    Novaković, Bojan; Hsieh, Henry H.; Gronchi, Giovanni F.

    2018-04-01

    The articles in this special issue are devoted to asteroids, small solar system bodies that primarily populate a region between the orbits of Mars and Jupiter, known as the asteroid belt, but can also be found throughout the Solar System. Asteroids are considered to be a key to understanding the formation and evolution of our planetary system. Their properties allow us to test current theoretical models and develop new theoretical concepts pertaining to evolutionary processes in the Solar System. There have been major advances in asteroid science in the last decade, and that trend continues. Eighteen papers accepted for this special issue cover a wide range of asteroid-related subjects, pushing the boundaries of our understanding of these intriguing objects even further. Here we provide the reader with a brief overview of these thrilling papers, with an invitation for interested scientists to read each work in detail for a better understanding of these recent cutting edge results. As many topics in asteroid science remain open challenges, we hope that this special issue will be an important reference point for future research on this compelling topic.

  16. EXPERIMENTAL INVESTIGATION OF CRITICAL FUNDAMENTAL ISSUES IN HAZARDOUS WASTE INCINERATION

    EPA Science Inventory

    The report gives results of a laboratory-scale program investigating several fundamental issues involved in hazardous waste incineration. The key experiment for each study was the measurement of waste destruction behavior in a sub-scale turbulent spray flame. (1) Atomization Qual...

  17. Web Services Security - Implementation and Evaluation Issues

    NASA Astrophysics Data System (ADS)

    Pimenidis, Elias; Georgiadis, Christos K.; Bako, Peter; Zorkadis, Vassilis

    Web services development is a key theme in the utilization the commercial exploitation of the semantic web. Paramount to the development and offering of such services is the issue of security features and they way these are applied in instituting trust amongst participants and recipients of the service. Implementing such security features is a major challenge to developers as they need to balance these with performance and interoperability requirements. Being able to evaluate the level of security offered is a desirable feature for any prospective participant. The authors attempt to address the issues of security requirements and evaluation criteria, while they discuss the challenges of security implementation through a simple web service application case.

  18. Salt II: Toward Security or Danger? A Balanced Account of the Key Issues in the Debate.

    ERIC Educational Resources Information Center

    Irwin, Wallace, Jr., Ed.; And Others

    Facts and controversial issues concerning SALT II (Strategic Arms Limitations Talks) are examined. The intent of the document is to enable non-specialists in military/strategic matters to arrive at their own conclusions. Central questions explored are: Is it possible to arrive at an agreement that will stabilize strategic arms competition and…

  19. Phosphoinositides: Key modulators of energy metabolism☆

    PubMed Central

    Bridges, Dave; Saltiel, Alan R.

    2014-01-01

    Phosphoinositides are key players in many trafficking and signaling pathways. Recent advances regarding the synthesis, location and functions of these lipids have dramatically improved our understanding of how and when these lipids are generated and what their roles are in animal physiology. In particular, phosphoinositides play a central role in insulin signaling, and manipulation of PtdIns(3,4,5)P3 levels in particular, may be an important potential therapeutic target for the alleviation of insulin resistance associated with obesity and the metabolic syndrome. In this article we review the metabolism, regulation and functional roles of phosphoinositides in insulin signaling and the regulation of energy metabolism. This article is part of a Special Issue entitled Phosphoinositides. PMID:25463477

  20. Ongoing ethical issues concerning authorship in biomedical journals: an integrative review

    PubMed Central

    Kornhaber, Rachel Anne; McLean, Loyola M; Baber, Rodney J

    2015-01-01

    Health professionals publishing within the field of health sciences continue to experience issues concerning appropriate authorship, which have clinical, ethical, and academic implications. This integrative review sought to explore the key issues concerning authorship from a bioethical standpoint, aiming to explore the key features of the authorship debate. Studies were identified through an electronic search, using the PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Scopus databases of peer-reviewed research, published between 2009 and 2014, limited to English language research, with search terms developed to reflect the current issues of authorship. From among the 279 papers identified, 20 research papers met the inclusion criteria. Findings were compiled and then arranged to identify themes and relationships. The review incorporated a wide range of authorship issues encompassing equal-credited authors, honorary (guest/gift) and ghost authorship, perception/experiences of authorship, and guidelines/policies. This review suggests that the International Committee of Medical Journal Editors’ (ICMJE) recommended guidelines for authorship are not reflected in current authorship practices within the domain of health sciences in both low-and high-impact-factor journals. This devaluing of the true importance of authorship has the potential to affect the validity of authorship, diminish the real contributions of the true authors, and negatively affect patient care. PMID:26257520

  1. Ongoing ethical issues concerning authorship in biomedical journals: an integrative review.

    PubMed

    Kornhaber, Rachel Anne; McLean, Loyola M; Baber, Rodney J

    2015-01-01

    Health professionals publishing within the field of health sciences continue to experience issues concerning appropriate authorship, which have clinical, ethical, and academic implications. This integrative review sought to explore the key issues concerning authorship from a bioethical standpoint, aiming to explore the key features of the authorship debate. Studies were identified through an electronic search, using the PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Scopus databases of peer-reviewed research, published between 2009 and 2014, limited to English language research, with search terms developed to reflect the current issues of authorship. From among the 279 papers identified, 20 research papers met the inclusion criteria. Findings were compiled and then arranged to identify themes and relationships. The review incorporated a wide range of authorship issues encompassing equal-credited authors, honorary (guest/gift) and ghost authorship, perception/experiences of authorship, and guidelines/policies. This review suggests that the International Committee of Medical Journal Editors' (ICMJE) recommended guidelines for authorship are not reflected in current authorship practices within the domain of health sciences in both low-and high-impact-factor journals. This devaluing of the true importance of authorship has the potential to affect the validity of authorship, diminish the real contributions of the true authors, and negatively affect patient care.

  2. Introduction to This Special Issue on Context-Aware Computing.

    ERIC Educational Resources Information Center

    Moran, Thomas P.; Dourish, Paul

    2001-01-01

    Discusses pervasive, or ubiquitous, computing; explains the notion of context; and defines context-aware computing as the key to disperse and enmesh computation into our lives. Considers context awareness in human-computer interaction and describes the broad topic areas of the essays included in this special issue. (LRW)

  3. Dilemmas of American Policy; Crucial Issues in Contemporary Society.

    ERIC Educational Resources Information Center

    Cook, Samuel DuBois; And Others

    This volume contains four papers dealing with key social issues confronting American society; racial conflict; education (especially concerning national policies and goals); rationale for limited war for a nonmilitaristic nation; and the generation gap. Dr. Cook discusses black identity and white response and the problem of inculcating hope where…

  4. Financial Viability of Institutions. Issues in Post-Secondary Education.

    ERIC Educational Resources Information Center

    Jenny, Hans H.

    Financial viability in postsecondary education is considered as part of the Postsecondary Education Core Design Project sponsored by the National Center for Education Statistics. Financial viability is defined within the scope of postsecondary education, and key policy issues at the national, state, and institutional levels are identified.…

  5. A Polynomial Subset-Based Efficient Multi-Party Key Management System for Lightweight Device Networks.

    PubMed

    Mahmood, Zahid; Ning, Huansheng; Ghafoor, AtaUllah

    2017-03-24

    Wireless Sensor Networks (WSNs) consist of lightweight devices to measure sensitive data that are highly vulnerable to security attacks due to their constrained resources. In a similar manner, the internet-based lightweight devices used in the Internet of Things (IoT) are facing severe security and privacy issues because of the direct accessibility of devices due to their connection to the internet. Complex and resource-intensive security schemes are infeasible and reduce the network lifetime. In this regard, we have explored the polynomial distribution-based key establishment schemes and identified an issue that the resultant polynomial value is either storage intensive or infeasible when large values are multiplied. It becomes more costly when these polynomials are regenerated dynamically after each node join or leave operation and whenever key is refreshed. To reduce the computation, we have proposed an Efficient Key Management (EKM) scheme for multiparty communication-based scenarios. The proposed session key management protocol is established by applying a symmetric polynomial for group members, and the group head acts as a responsible node. The polynomial generation method uses security credentials and secure hash function. Symmetric cryptographic parameters are efficient in computation, communication, and the storage required. The security justification of the proposed scheme has been completed by using Rubin logic, which guarantees that the protocol attains mutual validation and session key agreement property strongly among the participating entities. Simulation scenarios are performed using NS 2.35 to validate the results for storage, communication, latency, energy, and polynomial calculation costs during authentication, session key generation, node migration, secure joining, and leaving phases. EKM is efficient regarding storage, computation, and communication overhead and can protect WSN-based IoT infrastructure.

  6. Location-Aware Dynamic Session-Key Management for Grid-Based Wireless Sensor Networks

    PubMed Central

    Chen, Chin-Ling; Lin, I-Hsien

    2010-01-01

    Security is a critical issue for sensor networks used in hostile environments. When wireless sensor nodes in a wireless sensor network are distributed in an insecure hostile environment, the sensor nodes must be protected: a secret key must be used to protect the nodes transmitting messages. If the nodes are not protected and become compromised, many types of attacks against the network may result. Such is the case with existing schemes, which are vulnerable to attacks because they mostly provide a hop-by-hop paradigm, which is insufficient to defend against known attacks. We propose a location-aware dynamic session-key management protocol for grid-based wireless sensor networks. The proposed protocol improves the security of a secret key. The proposed scheme also includes a key that is dynamically updated. This dynamic update can lower the probability of the key being guessed correctly. Thus currently known attacks can be defended. By utilizing the local information, the proposed scheme can also limit the flooding region in order to reduce the energy that is consumed in discovering routing paths. PMID:22163606

  7. Location-aware dynamic session-key management for grid-based Wireless Sensor Networks.

    PubMed

    Chen, Chin-Ling; Lin, I-Hsien

    2010-01-01

    Security is a critical issue for sensor networks used in hostile environments. When wireless sensor nodes in a wireless sensor network are distributed in an insecure hostile environment, the sensor nodes must be protected: a secret key must be used to protect the nodes transmitting messages. If the nodes are not protected and become compromised, many types of attacks against the network may result. Such is the case with existing schemes, which are vulnerable to attacks because they mostly provide a hop-by-hop paradigm, which is insufficient to defend against known attacks. We propose a location-aware dynamic session-key management protocol for grid-based wireless sensor networks. The proposed protocol improves the security of a secret key. The proposed scheme also includes a key that is dynamically updated. This dynamic update can lower the probability of the key being guessed correctly. Thus currently known attacks can be defended. By utilizing the local information, the proposed scheme can also limit the flooding region in order to reduce the energy that is consumed in discovering routing paths.

  8. America's People: An Imperiled Resource. National Urban Policy Issues for a New Federal Administration.

    ERIC Educational Resources Information Center

    National Association of State Universities and Land Grant Colleges, Washington, DC.

    This report seeks to identify and make policy recommendations concerning major urban issues confronting the Bush Administration. The Division of Urban Affairs of the National Association of State Universities and Land-Grant Colleges (NASULGC) established working groups and commissioned papers on the following six key urban policy issues: (1)…

  9. Safety issues with herbal products.

    PubMed

    Marrone, C M

    1999-12-01

    To review safety issues associated with the use of herbal products. Literature accessed through MEDLINE and other Internet search engines. Key search terms included herbs, dietary supplements, and safety. A misconception exists among consumers that herbal remedies are safe because they are natural. In an effort to provide healthcare practitioners with information necessary for a patient discussion, a review of safety concerns with herbal products was conducted. Several safety concerns exist with herbal products including lack of safety data, absence of quality-control requirements for potency and purity, and lenient labeling standards.

  10. Ethical Issues in Transnational Eye Banking.

    PubMed

    Martin, Dominique E; Kelly, Richard; Jones, Gary L A; Machin, Heather; Pollock, Graeme A

    2017-02-01

    To review ethical issues that may arise in the setting of transnational eye banking activities, such as when exporting or importing corneal tissue for transplantation. A principle-based normative analysis of potential common dilemmas in transnational eye banking activities was performed. Transnational activities in eye banking, like those in other fields involving procurement and use of medical products of human origin, may present a number of ethical issues for policy makers and professionals. Key ethical concerns include the potential impact of export or import activities on self-sufficiency of corneal tissue supply within exporting and importing countries; potential disclosure requirements when obtaining consent or authorization for ocular tissue donation when donations may be exported; and difficulties inherent in assuring equity in the allocation of tissues available for export and in establishing and respecting standards of safety and quality across different jurisdictions. Further analysis of specific ethical issues in eye banking is necessary to inform development of guidelines and other governance tools that will assist policy makers and professionals to support ethical practice.

  11. Novel Multi-Party Quantum Key Agreement Protocol with G-Like States and Bell States

    NASA Astrophysics Data System (ADS)

    Min, Shi-Qi; Chen, Hua-Ying; Gong, Li-Hua

    2018-03-01

    A significant aspect of quantum cryptography is quantum key agreement (QKA), which ensures the security of key agreement protocols by quantum information theory. The fairness of an absolute security multi-party quantum key agreement (MQKA) protocol demands that all participants can affect the protocol result equally so as to establish a shared key and that nobody can determine the shared key by himself/herself. We found that it is difficult for the existing multi-party quantum key agreement protocol to withstand the collusion attacks. Put differently, it is possible for several cooperated and untruthful participants to determine the final key without being detected. To address this issue, based on the entanglement swapping between G-like state and Bell states, a new multi-party quantum key agreement protocol is put forward. The proposed protocol makes full use of EPR pairs as quantum resources, and adopts Bell measurement and unitary operation to share a secret key. Besides, the proposed protocol is fair, secure and efficient without involving a third party quantum center. It demonstrates that the protocol is capable of protecting users' privacy and meeting the requirement of fairness. Moreover, it is feasible to carry out the protocol with existing technologies.

  12. Novel Multi-Party Quantum Key Agreement Protocol with G-Like States and Bell States

    NASA Astrophysics Data System (ADS)

    Min, Shi-Qi; Chen, Hua-Ying; Gong, Li-Hua

    2018-06-01

    A significant aspect of quantum cryptography is quantum key agreement (QKA), which ensures the security of key agreement protocols by quantum information theory. The fairness of an absolute security multi-party quantum key agreement (MQKA) protocol demands that all participants can affect the protocol result equally so as to establish a shared key and that nobody can determine the shared key by himself/herself. We found that it is difficult for the existing multi-party quantum key agreement protocol to withstand the collusion attacks. Put differently, it is possible for several cooperated and untruthful participants to determine the final key without being detected. To address this issue, based on the entanglement swapping between G-like state and Bell states, a new multi-party quantum key agreement protocol is put forward. The proposed protocol makes full use of EPR pairs as quantum resources, and adopts Bell measurement and unitary operation to share a secret key. Besides, the proposed protocol is fair, secure and efficient without involving a third party quantum center. It demonstrates that the protocol is capable of protecting users' privacy and meeting the requirement of fairness. Moreover, it is feasible to carry out the protocol with existing technologies.

  13. Scaling-up HIV responses with key populations in West Africa.

    PubMed

    Wheeler, Tisha; Wolf, R Cameron; Kapesa, Laurent; Cheng Surdo, Alison; Dallabetta, Gina

    2015-03-01

    Despite decades of HIV responses in pockets of West and Central Africa (WCA), the HIV response with key populations remains an understudied area. Recently, there has been a proliferation of studies highlighting epidemiologic and behavioral data that challenge attitudes of complacency among donors and country governments uncomfortable in addressing key populations. The articles in this series highlight new studies that provide a better understanding of the epidemiologic and structural burden facing key populations in the WCA region and how to improve responses through more effective targeting. Key populations face pervasive structural barriers including institutional and sexual violence and an intersection of stigma, criminalization, and marginalization as sexual minorities. Despite decades of smaller interventions that have shown the importance of integrated services for key populations, there remains incongruent provision of outreach or testing or family planning pointing to sustained risk. There remains an incongruent resource provision for key populations where they shoulder the burden of HIV and their access to services alone could turn around HIV epidemics within the region. These proximal and distal determinants must be addressed in regional efforts, led by the community, and resourced for scale, targeting those most at risk for the acquisition and transmission of HIV. This special issue builds the knowledge base for the region focusing on interventions that remove barriers to service access including treatment uptake for those living with HIV. Better analysis and use of data for strategic planning are shown to lead to more effective targeting of prevention, care, and HIV treatment programs with key populations. These articles further demonstrate the immediate need for comprehensive action to address HIV among key populations throughout the WCA region.

  14. Triple symmetric key cryptosystem for data security

    NASA Astrophysics Data System (ADS)

    Fuzail, C. Md; Norman, Jasmine; Mangayarkarasi, R.

    2017-11-01

    As the technology is getting spreads in the macro seconds of speed and in which the trend changing era from human to robotics the security issue is also getting increased. By means of using machine attacks it is very easy to break the cryptosystems in very less amount of time. Cryptosystem is a process which provides the security in all sorts of processes, communications and transactions to be done securely with the help of electronical mechanisms. Data is one such thing with the expanded implication and possible scraps over the collection of data to secure predominance and achievement, Information Security is the process where the information is protected from invalid and unverified accessibilities and data from mishandling. So the idea of Information Security has risen. Symmetric key which is also known as private key.Whereas the private key is mostly used to attain the confidentiality of data. It is a dynamic topic which can be implemented over different applications like android, wireless censor networks, etc. In this paper, a new mathematical manipulation algorithm along with Tea cryptosystem has been implemented and it can be used for the purpose of cryptography. The algorithm which we proposed is straightforward and more powerful and it will authenticate in harder way and also it will be very difficult to break by someone without knowing in depth about its internal mechanisms.

  15. Learning Outcomes as a Key Concept in Policy Documents throughout Policy Changes

    ERIC Educational Resources Information Center

    Prøitz, Tine Sophie

    2015-01-01

    Learning outcomes can be considered to be a key concept in a changing education policy landscape, enhancing aspects such as benchmarking and competition. Issues relating to concepts of performance have a long history of debate within the field of education. Today, the concept of learning outcomes has become central in education policy development,…

  16. Orientation Effects in Fault Reactivation in Geological CO2 Sequestration

    NASA Astrophysics Data System (ADS)

    Castelletto, N.; Ferronato, M.; Gambolati, G.; Janna, C.; Teatini, P.

    2012-12-01

    Geological CO2 sequestration remains one of the most promising option for reducing the greenhouse gases emission. The accurate simulation of the complex coupled physical processes occurring during the injection and the post-injection stage represents a key issue for investigating the feasibility and the safety of the sequestration. The fluid-dynamical and geochemical aspects related to sequestering CO2 underground have been widely debated in the scientific literature over more than one decade. Recently, the importance of geomechanical processes has been widely recognized. In the present modeling study, we focus on fault reactivation induced by injection, an essential aspect for the evaluation of CO2 sequestration projects that needs to be adequately investigated to avoid the generation of preferential leaking path for CO2 and the related risk of induced seismicity. We use a geomechanical model based on the structural equations of poroelasticity solved by the Finite Element (FE) - Interface Element (IE) approach. Standard FEs are used to represent a continuum, while IEs prove especially suited to assess the relative displacements of adjacent elements such as the opening and slippage of existing faults or the generation of new fractures [1]. The IEs allow for the modeling of fault mechanics using an elasto-plastic constitutive law based on the Mohr-Coulomb failure criterion. We analyze the reactivation of a single fault in a synthetic reservoir by varying the fault orientation and size, hydraulic conductivity of the faulted zone, initial vertical and horizontal stress state and Mohr-Coulomb parameters (i.e., friction angle and cohesion). References: [1] Ferronato, M., G. Gambolati, C. Janna, and P. Teatini (2008), Numerical modeling of regional faults in land subsidence prediction above gas/oil reservoirs, Int. J. Numer. Anal. Methods Geomech., 32, 633-657.

  17. Multiscale analysis and computation for flows in heterogeneous media

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

    Efendiev, Yalchin; Hou, T. Y.; Durlofsky, L. J.

    Our work in this project is aimed at making fundamental advances in multiscale methods for flow and transport in highly heterogeneous porous media. The main thrust of this research is to develop a systematic multiscale analysis and efficient coarse-scale models that can capture global effects and extend existing multiscale approaches to problems with additional physics and uncertainties. A key emphasis is on problems without an apparent scale separation. Multiscale solution methods are currently under active investigation for the simulation of subsurface flow in heterogeneous formations. These procedures capture the effects of fine-scale permeability variations through the calculation of specialized coarse-scalemore » basis functions. Most of the multiscale techniques presented to date employ localization approximations in the calculation of these basis functions. For some highly correlated (e.g., channelized) formations, however, global effects are important and these may need to be incorporated into the multiscale basis functions. Other challenging issues facing multiscale simulations are the extension of existing multiscale techniques to problems with additional physics, such as compressibility, capillary effects, etc. In our project, we explore the improvement of multiscale methods through the incorporation of additional (single-phase flow) information and the development of a general multiscale framework for flows in the presence of uncertainties, compressible flow and heterogeneous transport, and geomechanics. We have considered (1) adaptive local-global multiscale methods, (2) multiscale methods for the transport equation, (3) operator-based multiscale methods and solvers, (4) multiscale methods in the presence of uncertainties and applications, (5) multiscale finite element methods for high contrast porous media and their generalizations, and (6) multiscale methods for geomechanics. Below, we present a brief overview of each of these contributions.« less

  18. 3D Printing and Digital Rock Physics for the Geosciences

    NASA Astrophysics Data System (ADS)

    Martinez, M. J.; Yoon, H.; Dewers, T. A.

    2014-12-01

    Imaging techniques for the analysis of porous structures have revolutionized our ability to quantitatively characterize geomaterials. For example, digital representations of rock from CT images and physics modeling based on these pore structures provide the opportunity to further advance our quantitative understanding of fluid flow, geomechanics, and geochemistry, and the emergence of coupled behaviors. Additive manufacturing, commonly known as 3D printing, has revolutionized production of custom parts, to the point where parts might be cheaper to print than to make by traditional means in a plant and ship. Some key benefits of additive manufacturing include short lead times, complex shapes, parts on demand, zero required inventory and less material waste. Even subtractive processing, such as milling and etching, may be economized by additive manufacturing. For the geosciences, recent advances in 3D printing technology may be co-opted to print reproducible porous structures derived from CT-imaging of actual rocks for experimental testing. The use of 3D printed microstructure allows us to surmount typical problems associated with sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Together, imaging, digital rocks and 3D printing potentially enables a new workflow for understanding coupled geophysical processes in a real, but well-defined setting circumventing typical issues associated with reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will discuss the possibilities that the marriage of these technologies can bring to geosciences, including examples from our current research initiatives in developing constitutive laws for transport and geomechanics via digital rock physics. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of

  19. Exploring key factors in online shopping with a hybrid model.

    PubMed

    Chen, Hsiao-Ming; Wu, Chia-Huei; Tsai, Sang-Bing; Yu, Jian; Wang, Jiangtao; Zheng, Yuxiang

    2016-01-01

    Nowadays, the web increasingly influences retail sales. An in-depth analysis of consumer decision-making in the context of e-business has become an important issue for internet vendors. However, factors affecting e-business are complicated and intertwined. To stimulate online sales, understanding key influential factors and causal relationships among the factors is important. To gain more insights into this issue, this paper introduces a hybrid method, which combines the Decision Making Trial and Evaluation Laboratory (DEMATEL) with the analytic network process, called DANP method, to find out the driving factors that influence the online business mostly. By DEMATEL approach the causal graph showed that "online service" dimension has the highest degree of direct impact on other dimensions; thus, the internet vendor is suggested to made strong efforts on service quality throughout the online shopping process. In addition, the study adopted DANP to measure the importance of key factors, among which "transaction security" proves to be the most important criterion. Hence, transaction security should be treated with top priority to boost the online businesses. From our study with DANP approach, the comprehensive information can be visually detected so that the decision makers can spotlight on the root causes to develop effectual actions.

  20. KEY COMPARISON: Final report on international key comparison CCQM-K53: Oxygen in nitrogen

    NASA Astrophysics Data System (ADS)

    Lee, Jeongsoon; Bok Lee, Jin; Moon, Dong Min; Seog Kim, Jin; van der Veen, Adriaan M. H.; Besley, Laurie; Heine, Hans-Joachim; Martin, Belén; Konopelko, L. A.; Kato, Kenji; Shimosaka, Takuya; Perez Castorena, Alejandro; Macé, Tatiana; Milton, Martin J. T.; Kelley, Mike; Guenther, Franklin; Botha, Angelique

    2010-01-01

    Gravimetry is used as the primary method for the preparation of primary standard gas mixtures in most national metrology institutes, and it requires the combined abilities of purity assessment, weighing technique and analytical skills. At the CCQM GAWG meeting in October 2005, it was agreed that KRISS should coordinate a key comparison, CCQM-K53, on the gravimetric preparation of gas, at a level of 100 µmol/mol of oxygen in nitrogen. KRISS compared the gravimetric value of each cylinder with an analytical instrument. A preparation for oxygen gas standard mixture requires particular care to be accurate, because oxygen is a major component of the atmosphere. Key issues for this comparison are related to (1) the gravimetric technique which needs at least two steps for dilution, (2) oxygen impurity in nitrogen, and (3) argon impurity in nitrogen. The key comparison reference value is obtained from the linear regression line (with origin) of a selected set of participants. The KCRV subset, except one, agree with each other. The standard deviation of the x-residuals of this group (which consists of NMIJ, VSL, NIST, NPL, BAM, KRISS and CENAM) is 0.056 µmol/mol and consistent with the uncertainties given to their standard mixtures. The standard deviation of the residuals of all participating laboratory is 0.182 µmol/mol. With respect to impurity analysis, overall argon amounts of the cylinders are in the region of about 3 µmol/mol however; four cylinders showed an argon amount fraction over 10 µmol/mol. Two of these are inconsistent with the KCRV subset. The explicit separation between two peaks of oxygen and argon in the GC chromatogram is essential to maintain analytical capability. Additionally oxygen impurity analysis in nitrogen is indispensable to ensure the preparative capability. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The

  1. Simple Web-based interactive key development software (WEBiKEY) and an example key for Kuruna (Poaceae: Bambusoideae)1

    PubMed Central

    Attigala, Lakshmi; De Silva, Nuwan I.; Clark, Lynn G.

    2016-01-01

    Premise of the study: Programs that are user-friendly and freely available for developing Web-based interactive keys are scarce and most of the well-structured applications are relatively expensive. WEBiKEY was developed to enable researchers to easily develop their own Web-based interactive keys with fewer resources. Methods and Results: A Web-based multiaccess identification tool (WEBiKEY) was developed that uses freely available Microsoft ASP.NET technologies and an SQL Server database for Windows-based hosting environments. WEBiKEY was tested for its usability with a sample data set, the temperate woody bamboo genus Kuruna (Poaceae). Conclusions: WEBiKEY is freely available to the public and can be used to develop Web-based interactive keys for any group of species. The interactive key we developed for Kuruna using WEBiKEY enables users to visually inspect characteristics of Kuruna and identify an unknown specimen as one of seven possible species in the genus. PMID:27144109

  2. Information processing in bacteria: memory, computation, and statistical physics: a key issues review

    NASA Astrophysics Data System (ADS)

    Lan, Ganhui; Tu, Yuhai

    2016-05-01

    Living systems have to constantly sense their external environment and adjust their internal state in order to survive and reproduce. Biological systems, from as complex as the brain to a single E. coli cell, have to process these data in order to make appropriate decisions. How do biological systems sense external signals? How do they process the information? How do they respond to signals? Through years of intense study by biologists, many key molecular players and their interactions have been identified in different biological machineries that carry out these signaling functions. However, an integrated, quantitative understanding of the whole system is still lacking for most cellular signaling pathways, not to say the more complicated neural circuits. To study signaling processes in biology, the key thing to measure is the input-output relationship. The input is the signal itself, such as chemical concentration, external temperature, light (intensity and frequency), and more complex signals such as the face of a cat. The output can be protein conformational changes and covalent modifications (phosphorylation, methylation, etc), gene expression, cell growth and motility, as well as more complex output such as neuron firing patterns and behaviors of higher animals. Due to the inherent noise in biological systems, the measured input-output dependence is often noisy. These noisy data can be analysed by using powerful tools and concepts from information theory such as mutual information, channel capacity, and the maximum entropy hypothesis. This information theory approach has been successfully used to reveal the underlying correlations between key components of biological networks, to set bounds for network performance, and to understand possible network architecture in generating observed correlations. Although the information theory approach provides a general tool in analysing noisy biological data and may be used to suggest possible network architectures in

  3. Information processing in bacteria: memory, computation, and statistical physics: a key issues review.

    PubMed

    Lan, Ganhui; Tu, Yuhai

    2016-05-01

    Living systems have to constantly sense their external environment and adjust their internal state in order to survive and reproduce. Biological systems, from as complex as the brain to a single E. coli cell, have to process these data in order to make appropriate decisions. How do biological systems sense external signals? How do they process the information? How do they respond to signals? Through years of intense study by biologists, many key molecular players and their interactions have been identified in different biological machineries that carry out these signaling functions. However, an integrated, quantitative understanding of the whole system is still lacking for most cellular signaling pathways, not to say the more complicated neural circuits. To study signaling processes in biology, the key thing to measure is the input-output relationship. The input is the signal itself, such as chemical concentration, external temperature, light (intensity and frequency), and more complex signals such as the face of a cat. The output can be protein conformational changes and covalent modifications (phosphorylation, methylation, etc), gene expression, cell growth and motility, as well as more complex output such as neuron firing patterns and behaviors of higher animals. Due to the inherent noise in biological systems, the measured input-output dependence is often noisy. These noisy data can be analysed by using powerful tools and concepts from information theory such as mutual information, channel capacity, and the maximum entropy hypothesis. This information theory approach has been successfully used to reveal the underlying correlations between key components of biological networks, to set bounds for network performance, and to understand possible network architecture in generating observed correlations. Although the information theory approach provides a general tool in analysing noisy biological data and may be used to suggest possible network architectures in

  4. Mexican Americans' Educational Barriers and Progress: Is the Magic Key within Reach? PERSPECTIVAS: Issues in Higher Education Policy and Practice. Issue No. 5, Spring 2016

    ERIC Educational Resources Information Center

    Zambrana, Ruth Enid; Hurtado, Sylvia

    2016-01-01

    This policy brief is based on the edited book "The Magic Key: The Educational Journey of Mexican Americans from K-12 to College and Beyond" (Zambrana & Hurtado, 2015a), which focuses on the experiences of Mexican Americans in education. Drawing from an interdisciplinary corpus of work, the authors move beyond the rhetoric of progress…

  5. Transportation Security: Issues for the 111th Congress

    DTIC Science & Technology

    2009-05-15

    results of covert testing of airport security checkpoints demonstrating deficiencies in detecting improvised explosives and incendiary devices...34 A key issue in the debate over aviation security immediately following September 11, 2001, was whether airport security screeners should be...intentional wrongdoing on the part of airport security screeners, whether they be federal or private. Nonetheless, while the pilot program airports

  6. Problems and issues for short-haul air transportation.

    NASA Technical Reports Server (NTRS)

    Vittek, J. F., Jr.

    1972-01-01

    The problems of developing an efficient short-haul air system are not primarily technical, but economic and political. The key issues are whether the community will accept new and expanded air facilities, what standards of service the passengers will demand and how the system will evolve. The solutions recommended are national in scope and require the federal government to take a leading role.

  7. Beacons In Brief. P/PV In Brief. Issue 2

    ERIC Educational Resources Information Center

    Blank, Susan; Farley, Chelsea

    2004-01-01

    This second issue in P/PV's "In Brief" series focuses on the San Francisco Beacon Initiative and P/PV's recently released evaluation results. The Beacon Initiative established after-school programs in eight public schools in low-income San Francisco neighborhoods. P/PV's 36-month evaluation examined key developmental and academic outcomes.…

  8. Youth in Northern Ireland: Introduction to the Special Issue.

    ERIC Educational Resources Information Center

    Percy, Andrew

    2000-01-01

    Introduces a collection of articles that represent some of the research and policy analysis of key issues affecting the lives of young people currently living in Northern Ireland, which is in the midst of an unparalleled political and social transformation. The articles focus on crime, drug use, criminal justice, families, divorce, and youth…

  9. Collaboration, integration and change in children's services: critical issues and key ingredients.

    PubMed

    Horwath, Jan; Morrison, Tony

    2007-01-01

    Government and state policy, irrespective of jurisdiction, increasingly require and indeed specify the nature of collaboration with regard to the delivery of child welfare services for maltreated children. The rationale for collaboration appears obvious in as much as it is aimed at promoting multidisciplinary practice in order to meet the needs of the vulnerable child. However, collaboration, whilst a useful and motivating concept, is in reality far from straightforward and contains complexities and ambiguities. The aim of this paper is to explore these complexities and ambiguities to provide an overview of key developmental frameworks relevant to the creation and maintenance of strategic high-level multiagency partnerships. The authors begin by exploring the characteristic features of different levels of multiagency collaboration that is communication, co-operation, co-ordination, coalition, and integration. As the emphasis in a variety of jurisdictions in the Western world is on the highest levels of collaboration namely coalition and service integration this is the focus of the paper. The authors synthesize the main literature in the field to consider the critical elements for effective collaborative endeavors at this level including predisposing factors, mandate, leadership, machinery, process, and outcomes. The paper concludes by recognizing that the drive towards integrated services is occurring in a climate of continuing change. The need to identify the impact of such an environment when managing multiagency partnerships is explored using five steps to change.

  10. Design issues for lunar in situ aluminum/oxygen propellant rocket engines

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.

    1992-01-01

    Design issues for lunar ascent and lunar descent rocket engines fueled by aluminum/oxygen propellant produced in situ at the lunar surface were evaluated. Key issues are discussed which impact the design of these rockets: aluminum combustion, throat erosion, and thrust chamber cooling. Four engine concepts are presented, and the impact of combustion performance, throat erosion and thrust chamber cooling on overall engine design are discussed. The advantages and disadvantages of each engine concept are presented.

  11. Global quality imaging: emerging issues.

    PubMed

    Lau, Lawrence S; Pérez, Maria R; Applegate, Kimberly E; Rehani, Madan M; Ringertz, Hans G; George, Robert

    2011-07-01

    Quality imaging may be described as "a timely access to and delivery of integrated and appropriate procedures, in a safe and responsive practice, and a prompt delivery of an accurately interpreted report by capable personnel in an efficient, effective, and sustainable manner." For this article, radiation safety is considered as one of the key quality elements. The stakeholders are the drivers of quality imaging. These include those that directly provide or use imaging procedures and others indirectly supporting the system. Imaging is indispensable in health care, and its use has greatly expanded worldwide. Globalization, consumer sophistication, communication and technological advances, corporatization, rationalization, service outsourcing, teleradiology, workflow modularization, and commoditization are reshaping practice. This article defines the emerging issues; an earlier article in the May 2011 issue described possible improvement actions. The issues that could threaten the quality use of imaging for all countries include workforce shortage; increased utilization, population radiation exposure, and cost; practice changes; and efficiency drive and budget constraints. In response to these issues, a range of quality improvement measures, strategies, and actions are used to maximize the benefits and minimize the risks. The 3 measures are procedure justification, optimization of image quality and radiation protection, and error prevention. The development and successful implementation of such improvement actions require leadership, collaboration, and the active participation of all stakeholders to achieve the best outcomes that we all advocate. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  12. Quantum key management

    DOEpatents

    Hughes, Richard John; Thrasher, James Thomas; Nordholt, Jane Elizabeth

    2016-11-29

    Innovations for quantum key management harness quantum communications to form a cryptography system within a public key infrastructure framework. In example implementations, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a Merkle signature scheme (using Winternitz one-time digital signatures or other one-time digital signatures, and Merkle hash trees) to constitute a cryptography system. More generally, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a hash-based signature scheme. This provides a secure way to identify, authenticate, verify, and exchange secret cryptographic keys. Features of the quantum key management innovations further include secure enrollment of users with a registration authority, as well as credential checking and revocation with a certificate authority, where the registration authority and/or certificate authority can be part of the same system as a trusted authority for quantum key distribution.

  13. Teaching and Studying Social Issues: Major Programs and Approaches. Research in Curriculum and Instruction

    ERIC Educational Resources Information Center

    Totten, Samuel, Ed.; Pedersen, Jon, Ed.

    2010-01-01

    "Teaching and Studying Social Issues: Major Programs and Approaches" focuses on many of the major innovations developed over the past 100 years by noted educators to assist students in the study and analysis of key social issues that impact their lives and society. This book complements earlier books that address other aspects of studying and…

  14. "They Did Things Differently Then": Diversity and Challenge from Key Stage 1

    ERIC Educational Resources Information Center

    Bracey, Paul; Jackson, Darius; Gove-Humphries, Alison

    2011-01-01

    This paper is based on the premise that controversial issues related to diversity are an important aspect of teaching and learning with all pupils. It was stimulated by a newspaper article which criticised teaching Key Stage 1 (5-7-year-old children) about Grace O'Malley, an Irish Queen. We argue that sixteenth century Anglo-Irish relations can be…

  15. Qualitative Approaches to Research in Counselling and Psychotherapy: Issues and Challenges.

    ERIC Educational Resources Information Center

    McLeod, John

    1996-01-01

    Discusses key issues which address the distinctive dilemmas and challenges associated with qualitative approaches to evaluating counseling. Investigates such concerns as relationships with research participants, ethics, reflexivity, methodological choice, communicability, perspective, and obviousness. Makes some suggestions regarding the link…

  16. A Polynomial Subset-Based Efficient Multi-Party Key Management System for Lightweight Device Networks

    PubMed Central

    Mahmood, Zahid; Ning, Huansheng; Ghafoor, AtaUllah

    2017-01-01

    Wireless Sensor Networks (WSNs) consist of lightweight devices to measure sensitive data that are highly vulnerable to security attacks due to their constrained resources. In a similar manner, the internet-based lightweight devices used in the Internet of Things (IoT) are facing severe security and privacy issues because of the direct accessibility of devices due to their connection to the internet. Complex and resource-intensive security schemes are infeasible and reduce the network lifetime. In this regard, we have explored the polynomial distribution-based key establishment schemes and identified an issue that the resultant polynomial value is either storage intensive or infeasible when large values are multiplied. It becomes more costly when these polynomials are regenerated dynamically after each node join or leave operation and whenever key is refreshed. To reduce the computation, we have proposed an Efficient Key Management (EKM) scheme for multiparty communication-based scenarios. The proposed session key management protocol is established by applying a symmetric polynomial for group members, and the group head acts as a responsible node. The polynomial generation method uses security credentials and secure hash function. Symmetric cryptographic parameters are efficient in computation, communication, and the storage required. The security justification of the proposed scheme has been completed by using Rubin logic, which guarantees that the protocol attains mutual validation and session key agreement property strongly among the participating entities. Simulation scenarios are performed using NS 2.35 to validate the results for storage, communication, latency, energy, and polynomial calculation costs during authentication, session key generation, node migration, secure joining, and leaving phases. EKM is efficient regarding storage, computation, and communication overhead and can protect WSN-based IoT infrastructure. PMID:28338632

  17. Introduction to special issue: moving forward in pediatric neuropsychology.

    PubMed

    Daly, Brian P; Giovannetti, Tania; Zabel, T Andrew; Chute, Douglas L

    2011-08-01

    This special issue of The Clinical Neuropsychologist focuses on advances in the emerging subspecialty of pediatric neuropsychology. The national and international contributions in this issue cover a range of key clinical, research, training, and professional issues specific to pediatric neuropsychology. The genesis for this project developed out of a series of talks at the Philadelphia Pediatric Neuropsychology Symposium in 2010, hosted by the Stein Family Fellow, the Department of Psychology of the College of Arts and Sciences at Drexel University, and the Philadelphia Neuropsychology Society. Articles that explore clinical practice issue focus on the assessment of special medical populations with congenital and/or acquired central nervous system insults. Research articles investigate the core features of developmental conditions, the use of technology in neuropsychological research studies, and large sample size genomic, neuropsychological, and imaging studies of under-represented populations. The final series of articles examine new considerations in training, advocacy, and subspecialty board certification that have emerged in pediatric neuropsychology. This introductory article provides an overview of the articles in this special issue and concluding thoughts about the future of pediatric neuropsychology.

  18. Exploring work-related issues on corporate sustainability.

    PubMed

    Brunoro, C M; Bolis, I; Sznelwar, L I

    2015-01-01

    In a research project about work-related issues and corporate sustainability conducted in Brazil, the goal was to better understand how work-related issues were addressed in the corporate context. Particularly, there are some specific initiatives that serve as guides to organizational decisions, which make their performance indicators for the context of corporate sustainability. 1) To explore the presence of work-related issues and their origins in corporate sustainability approach, analyzing a) corporate disclosures; b) sustainability guidelines that are identified as relevant in corporate disclosures; c) documents that are related to sustainable development and also identified as key-documents for these guidelines and initiatives. 2) To present the activity-centered ergonomics and psychodynamics of work contributions to work-related issues in a corporate sustainability approach. An exploratory study based on multiple sources of evidence that were performed from 2012 to 2013, including interviews with companies that engaged in corporate sustainability and document analysis using the content analysis approach. Work-related issues have been presented since the earliest sustainable development documents. It is feasible to construct an empirical framework for work-related issues and corporate sustainability approaches. 1) Although some authors argue that corporate sustainability has its roots based only on the environmental dimension, there is strong empirical evidence showing that social dimension aspects such as work-related issues have been present since the beginning. 2) Some indicators should be redesigned to more precisely translate the reality of some workplaces, particularly those indicators related to organizational design and mental health.

  19. Postsecondary Distance Education in Mexico and Worldwide: Issues and Considerations

    ERIC Educational Resources Information Center

    Becerra, Bertha Leticia Gonzalez; Almendra, Manuel Pio Rosales; Flores, Jose Daniel Corona

    2012-01-01

    Postsecondary distance education has attracted increasing attention in recent years, an understandable change when one considers that innovative approaches to distance education have offered opportunities to overcome some of the key challenges in traditional "brick and mortar" education. Nonetheless, there are a plethora of issues that…

  20. The role of the support worker in nursing homes: a consideration of key issues.

    PubMed

    Baldwin, Julie; Roberts, Julia D; Fitzpatrick, Joanne I; While, Alison; Cowan, David T

    2003-11-01

    The aim of this paper is to critically consider the role of the support worker in the nursing home sector and with particular reference to the United Kingdom situation. With the expansion of the nursing home sector, there is an increasing population of support workers in this field. Literature in this paper covers the period between 1989 and 2002, beginning with the build up to the introduction of the National Health Service and Community Care Act (available at: http://www.hmso.gov.uk), which necessitated a major shift between public and private sector employment. The findings of this paper indicate limited research, investigating the role of support workers in general and specifically those working in the nursing home sector. The literature suggests that the majority of the role focuses on direct patient care, however, a lack of role clarification was evident and differences emerged between the views of support workers and Registered Nurses regarding the place of support workers in the care process. In particular, support workers saw their role as similar to that of the Registered Nurse, although Registered Nurse regarded 'basic nursing care' as the key remit of the support worker role. The paper also indicated inadequate preparation and subsequent supervision of support workers. These key findings indicate that role clarification, appropriate preparation and a process of continuing development require careful consideration by managers if the positive contribution of this group of care workers is to be fully realized. Furthermore, while there exists no central source of funding to finance the role preparation and mentorship of support workers, training provision will remain ad hoc. Obtaining core funding would allow for the training and education of support workers to become standard practice, which, in turn, is more likely to lead to improvements in the planning and resourcing of care provision. Equally, further research is needed if the support worker role is to

  1. Geology, water-quality, hydrology, and geomechanics of the Cuyama Valley groundwater basin, California, 2008--12

    USGS Publications Warehouse

    Everett, Rhett; Gibbs, Dennis R.; Hanson, Randall T.; Sweetkind, Donald S.; Brandt, Justin T.; Falk, Sarah E.; Harich, Christopher R.

    2013-01-01

    To assess the water resources of the Cuyama Valley groundwater basin in Santa Barbara County, California, a series of cooperative studies were undertaken by the U.S. Geological Survey and the Santa Barbara County Water Agency. Between 2008 and 2012, geologic, water-quality, hydrologic and geomechanical data were collected from selected sites throughout the Cuyama Valley groundwater basin. Geologic data were collected from three multiple-well groundwater monitoring sites and included lithologic descriptions of the drill cuttings, borehole geophysical logs, temperature logs, as well as bulk density and sonic velocity measurements of whole-core samples. Generalized lithologic characterization from the monitoring sites indicated the water-bearing units in the subsurface consist of unconsolidated to partly consolidated sand, gravel, silt, clay, and occasional cobbles within alluvial fan and stream deposits. Analysis of geophysical logs indicated alternating layers of finer- and coarser-grained material that range from less than 1 foot to more than 20 feet thick. On the basis of the geologic data collected, the principal water-bearing units beneath the monitoring-well sites were found to be composed of younger alluvium of Holocene age, older alluvium of Pleistocene age, and the Tertiary-Quaternary Morales Formation. At all three sites, the contact between the recent fill and younger alluvium is approximately 20 feet below land surface. Water-quality samples were collected from 12 monitoring wells, 27 domestic and supply wells, 2 springs, and 4 surface-water sites and were analyzed for a variety of constituents that differed by site, but, in general, included trace elements; nutrients; dissolved organic carbon; major and minor ions; silica; total dissolved solids; alkalinity; total arsenic and iron; arsenic, chromium, and iron species; and isotopic tracers, including the stable isotopes of hydrogen and oxygen, activities of tritium, and carbon-14 abundance. Of the 39

  2. Cyberbulling among Children and Teens: A Pervasive Global Issue

    ERIC Educational Resources Information Center

    Eaton, Sarah Elaine

    2017-01-01

    This report is a compiliation of evidence-informed blog posts on cyberbulling among children and teens. It examines the issue of cyberbullying from the perspective of both the victim and the perpetrator. A key argument is that cyberbullying is a matter not only for the children involved, but also for their families and educators.

  3. The effect of touch-key size on the usability of In-Vehicle Information Systems and driving safety during simulated driving.

    PubMed

    Kim, Heejin; Kwon, Sunghyuk; Heo, Jiyoon; Lee, Hojin; Chung, Min K

    2014-05-01

    Investigating the effect of touch-key size on usability of In-Vehicle Information Systems (IVISs) is one of the most important research issues since it is closely related to safety issues besides its usability. This study investigated the effects of the touch-key size of IVISs with respect to safety issues (the standard deviation of lane position, the speed variation, the total glance time, the mean glance time, the mean time between glances, and the mean number of glances) and the usability of IVISs (the task completion time, error rate, subjective preference, and NASA-TLX) through a driving simulation. A total of 30 drivers participated in the task of entering 5-digit numbers with various touch-key sizes while performing simulated driving. The size of the touch-key was 7.5 mm, 12.5 mm, 17.5 mm, 22.5 mm and 27.5 mm, and the speed of driving was set to 0 km/h (stationary state), 50 km/h and 100 km/h. As a result, both the driving safety and the usability of the IVISs increased as the touch-key size increased up to a certain size (17.5 mm in this study), at which they reached asymptotes. We performed Fitts' law analysis of our data, and this revealed that the data from the dual task experiment did not follow Fitts' law. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Ethical Issues in Social Media Research for Public Health.

    PubMed

    Hunter, Ruth F; Gough, Aisling; O'Kane, Niamh; McKeown, Gary; Fitzpatrick, Aine; Walker, Tom; McKinley, Michelle; Lee, Mandy; Kee, Frank

    2018-03-01

    Social media (SM) offer huge potential for public health research, serving as a vehicle for surveillance, delivery of health interventions, recruitment to trials, collection of data, and dissemination. However, the networked nature of the data means they are riddled with ethical challenges, and no clear consensus has emerged as to the ethical handling of such data. This article outlines the key ethical concerns for public health researchers using SM and discusses how these concerns might best be addressed. Key issues discussed include privacy; anonymity and confidentiality; authenticity; the rapidly changing SM environment; informed consent; recruitment, voluntary participation, and sampling; minimizing harm; and data security and management. Despite the obvious need, producing a set of prescriptive guidelines for researchers using SM is difficult because the field is evolving quickly. What is clear, however, is that the ethical issues connected to SM-related public health research are also growing. Most importantly, public health researchers must work within the ethical principles set out by the Declaration of Helsinki that protect individual users first and foremost.

  5. Argumentation as a Strategy for Increasing Preservice Teachers' Understanding of Climate Change, a Key Global Socioscientific Issue

    ERIC Educational Resources Information Center

    Lambert, Julie L.; Bleicher, Robert E.

    2017-01-01

    Findings of this study suggest that scientific argumentation can play an effective role in addressing complex socioscientific issues (i.e. global climate change). This research examined changes in preservice teachers' knowledge and perceptions about climate change in an innovative undergraduate-level elementary science methods course. The…

  6. Ethical issues in a pediatric private practice.

    PubMed

    Jakubowitz, Melissa

    2011-11-01

    Building a successful pediatric private practice requires clinical expertise and an understanding of the business process, as well as familiarity with the American Speech-Language-Hearing Association Code of Ethics. This article provides an overview of the ethical issues that may be encountered when building a practice, including a look at marketing and advertising, financial management, privacy, and documentation. Ethically sound decision making is a key to a successful business. © Thieme Medical Publishers.

  7. Focus issue articles on emerging and re-emerging plant diseases

    USDA-ARS?s Scientific Manuscript database

    This review sums up the key findings of seventeen articles on emerging and re-emerging plant diseases that are designated for the July focus issue in Phytopathology. The emerging and re-emerging diseases discussed include those caused by three viral, six fungal, five oomycete, and four bacterial pa...

  8. Global trade and health: key linkages and future challenges.

    PubMed Central

    Bettcher, D. W.; Yach, D.; Guindon, G. E.

    2000-01-01

    Globalization of trade, marketing and investment has important implications for public health, both negative and positive. This article considers the implications of the single package of World Trade Organization (WTO) agreements for public health research and policy, focusing on three themes: commodities, intellectual property rights, and health services. The main aims of the analysis are as follows: to identify how trade issues are associated with the transnationalization of health risks and possible benefits; to identify key areas of research; and to suggest policy-relevant advice and interventions on trade and health issues. The next wave of international trade law will need to take more account of global public health issues. However, to become more engaged in global trade debates, the public health community must gain an understanding of the health effects of global trade agreements. It must also ensure that its own facts are correct, so that public health is not blindly used for political ends, such as justifying unwarranted economic protectionism. "Healthy trade" policies, based on firm empirical evidence and designed to improve health status, are an important step towards reaching a more sustainable form of trade liberalization. PMID:10885181

  9. Emerging ICT implementation issues in aged care.

    PubMed

    Kapadia, Vasvi; Ariani, Arni; Li, Junhua; Ray, Pradeep K

    2015-11-01

    Demand for aged care services continues to soar as a result of an aging population. This increasing demand requires more residential aged care facilities and healthcare workforce. One recommended solution is to keep older people in their homes longer and support their independent life through the use of information and communication technologies (ICT). However, the aged care sector is still in the early stages of adopting ICT. The aim of this study was to identify the key issues that affect the adoption of ICT in the aged care sector. A systematic literature review was undertaken and involved four steps. The first two steps aimed to identify and select relevant articles. Data was then extracted from the selected articles and identified issues were analyzed and grouped into three major categories. ICT adoption issues were categorized into different perspectives, representing older people, health professionals and management. Our findings showed that all three groups were mostly concerned with issues around behavior, cost and lack of technical skills. Findings reported in this study will help decision makers at aged care settings to systematically understand issues related to ICT adoption and thus proactively introduce interventions to improve use of ICT in this sector. On the basis of our findings, we suggest future research focus on the examination of aged care workflow and assessment of return on ICT investment. Copyright © 2015. Published by Elsevier Ireland Ltd.

  10. Fitness issues in the context of judicial proceedings.

    PubMed

    Samuels, Anthony; O'Driscoll, Colman; Allnutt, Stephen

    2007-06-01

    This paper provides a conceptual, historical and legislative overview of fitness issues. These include fitness to be interrogated or charged, to plead, to be tried and to be sentenced in the context of Australia and New Zealand. Legislation regarding fitness issues needs to strike a balance between protecting the rights of mentally impaired defendants to a fair trial process and recognizing that mental illness in itself does not absolutely preclude participation in a trial process or necessarily diminish criminal responsibility. Although the key determinants of fitness seem to be the ability to cope with court processes and communicate with counsel, the application of clinical judgement to legal criteria is not always straightforward.

  11. Pakistan: Key Current Issues and Developments

    DTIC Science & Technology

    2010-06-01

    unites many disparate groups in heightened anti-American sentiment.47 • Also in February, three U.S. soldiers were killed when a suicide car bomber...of 2009, or an average of about one every three days. Among the most gruesome were an October 28 car bombing at a market in Peshawar that killed some...Violence Drives Business From Peshawar,” Financial Times (London), January 4, 2010. 54 In recent examples, a March suicide car bombing of the

  12. Critical Issues: Keys to Successful Contracting

    ERIC Educational Resources Information Center

    Zopf, Michael

    2010-01-01

    In today's restrictive school-funding environment, many school districts are evaluating different strategies for providing noninstructional support services to preserve financial resources for the classroom. Among the strategies they are considering on a wide scale is the contracting of support functions, including pupil transportation, custodial…

  13. Early Intervention: Key Issues from Research.

    ERIC Educational Resources Information Center

    Fraser, Helen

    1998-01-01

    As the preschool and early years of schooling were becoming the focus of increasing attention, the Scottish Office Education and Industry Department commissioned a review of United Kingdom and international literature on the use of early intervention schemes for disadvantaged students. The resulting review presents evidence on the most appropriate…

  14. Presidential Opinions on Today's Key Issues.

    ERIC Educational Resources Information Center

    Budig, Gene A.

    1986-01-01

    Interviews with chief executives of large state universities by the chancellor of the University of Kansas are described. The need to work more closely with state officials, concern about faculty morale, new campus-statehouse initiatives to advance high technology and fuel state economic growth, and college athletics are discussed. (MLW)

  15. Contrasting speakers focus on key issues.

    PubMed

    2016-02-01

    Around 100 IHEEM Company Affiliate Members, their guests, and senior representatives from organisations including the Royal Academy of Engineering, IPEM, and CIBSE, as well as from the NHS and its associated construction and supply chains, attended a high-level IHEEM seminar titled Healthcare Estates 2020 in Westminster on 19 November Topics discussed ranged from how the healthcare estates sector is increasingly being asked to 'do more with less', to Lord Carter's team's initial findings on the 'productivity and efficiency' of NHS Trusts in England. The seminar was followed by a celebratory lunch at the House of Lords, where the keynote speaker was Royal Academy of Engineering CEO, Philip Greenish (see HEJ--January 2016).

  16. An investigation of how university sports team athletic therapists and physical therapists experience ethical issues.

    PubMed

    Riendeau, Catherine; Parent-Houle, Valérie; Lebel-Gabriel, Marie Eve; Gauvin, Patrick; Liu, Le Yu; Pearson, Isabelle; Hunt, Matthew R

    2015-03-01

    Qualitative study using interpretive description methodology. The purpose of this study was to better understand how ethical issues are experienced by university sports team athletic therapists and physical therapists. In clinical practice, sports teams are associated with a range of ethical issues. Issues commonly reported in the literature include confidentiality, return-to-play decisions, conflicts of interest, advertising, doping, and use of local anesthetic. To date, there has been limited examination of how athletic therapists and physical therapists involved with sports teams experience these ethical issues, and limited exploration of how these ethical issues, when encountered, are shaped by therapists' professional roles and responsibilities. Semi-structured interviews were conducted with 11 athletic or physical therapists working with sports teams in 5 Canadian provinces. The data were analyzed inductively, using a recursive approach and constant comparative techniques. Four key themes were developed relating to the participants' experiences of ethical issues: establishing and maintaining professional boundaries, striving for respectful and effective collaboration, seeking answers to ethical concerns, and living with the repercussions of challenging decisions. While many ethical issues reported by participants resemble those faced by sports medicine physicians, they are experienced in distinctive ways, due to differences in professional roles and identities. Issues concerning professional boundaries were also more prominent for the study participants than the literature has reported them to be for sports medicine physicians. Effective communication and enhanced collaboration appear to be key elements in managing these ethical challenges.

  17. Mechanical Controls on Halokinesis in Layered Evaporite Sequences: Insights from 2D Geomechanical Forward Models

    NASA Astrophysics Data System (ADS)

    Goteti, Rajesh; Agar, Susan M.; Brown, John P.; Ball, Philip; Zuhlke, Rainer

    2017-04-01

    stringers. A significant proportion of the bulk deviatoric strain is preferentially partitioned into the salt layers. Effective plastic shear strains within the sediment stringers generally remain low in the minibasin but can be significantly higher with attendant intense folding near the diapirs. In non-LES systems, the shape of a salt diapir is often used as indicator of relative rates of salt supply and sedimentation over geological time. However our models suggest that this rule-of-thumb may not apply in LES where the shape of the salt diapir is a function of the mechanical properties of the salt layers at various structural levels in addition to the relative rates of salt supply and sedimentation. Imaging challenges in LES may preclude placing strong constraints on structural timing based on interpretation of interfaces between the stringers and the salt diapir. In such situations, geomechanical forward modeling can be a useful tool in placing physics-based quantitative constraints on the timing of LES structures.

  18. Impact Assessment and Forecasts of Information and Telecommunications Technologies Applied to Education and Training. R&D in Information and Communication Based Learning Technology. Analysis of Key Issues for the Orientation of the Work of Sector Actors in the Framework of DELTA. Volume I--Executive Summary.

    ERIC Educational Resources Information Center

    Commission of the European Communities, Brussels (Belgium).

    This report, the first volume in a three volume set, summarizes the results of a study performed by the DELTA (Developing European Learning through Technological Advance) Unit in parallel with the projects underway in the research and development Exploratory Action. The report identifies the key issues, associated requirements and options, and…

  19. Distributed generation of shared RSA keys in mobile ad hoc networks

    NASA Astrophysics Data System (ADS)

    Liu, Yi-Liang; Huang, Qin; Shen, Ying

    2005-12-01

    Mobile Ad Hoc Networks is a totally new concept in which mobile nodes are able to communicate together over wireless links in an independent manner, independent of fixed physical infrastructure and centralized administrative infrastructure. However, the nature of Ad Hoc Networks makes them very vulnerable to security threats. Generation and distribution of shared keys for CA (Certification Authority) is challenging for security solution based on distributed PKI(Public-Key Infrastructure)/CA. The solutions that have been proposed in the literature and some related issues are discussed in this paper. The solution of a distributed generation of shared threshold RSA keys for CA is proposed in the present paper. During the process of creating an RSA private key share, every CA node only has its own private security. Distributed arithmetic is used to create the CA's private share locally, and that the requirement of centralized management institution is eliminated. Based on fully considering the Mobile Ad Hoc network's characteristic of self-organization, it avoids the security hidden trouble that comes by holding an all private security share of CA, with which the security and robustness of system is enhanced.

  20. Application of micropolar plasticity to post failure analysis in geomechanics

    NASA Astrophysics Data System (ADS)

    Manzari, Majid T.

    2004-08-01

    A micropolar elastoplastic model for soils is formulated and a series of finite element analyses are employed to demonstrate the use of a micropolar continuum in overcoming the numerical difficulties encountered in application of finite element method in standard Cauchy-Boltzmann continuum. Three examples of failure analysis involving a deep excavation, shallow foundation, and a retaining wall are presented. In all these cases, it is observed that the length scale introduced in the polar continuum regularizes the incremental boundary value problem and allows the numerical simulation to be continued until a clear collapse mechanism is achieved. The issue of grain size effect is also discussed. Copyright

  1. 77 FR 30508 - Open Meeting To Obtain Input for 2013 DoD 10 Key State Issues Impacting Service Members and Their...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... State Issues Impacting Service Members and Their Families AGENCY: Department of Defense. ACTION: Notice. SUMMARY: The public is invited to attend an open session to consider issues impacting Service members and their families that can best be resolved by state governments. Additionally, the public is invited to...

  2. Security, privacy, and confidentiality issues on the Internet.

    PubMed

    Kelly, Grant; McKenzie, Bruce

    2002-01-01

    We introduce the issues around protecting information about patients and related data sent via the Internet. We begin by reviewing three concepts necessary to any discussion about data security in a healthcare environment: privacy, confidentiality, and consent. We are giving some advice on how to protect local data. Authentication and privacy of e-mail via encryption is offered by Pretty Good Privacy (PGP) and Secure Multipurpose Internet Mail Extensions (S/MIME). The de facto Internet standard for encrypting Web-based information interchanges is Secure Sockets Layer (SSL), more recently known as Transport Layer Security or TLS. There is a public key infrastructure process to 'sign' a message whereby the private key of an individual can be used to 'hash' the message. This can then be verified against the sender's public key. This ensures the data's authenticity and origin without conferring privacy, and is called a 'digital signature'. The best protection against viruses is not opening e-mails from unknown sources or those containing unusual message headers.

  3. Endangered species and nature conservation: science issues and challenges.

    PubMed

    Szaro, Robert C

    2008-06-01

    The issues and challenges facing us in ensuring the survival of as many species and ecosystems as possible call for a renewed research focus to address how to improve management strategies and policy making now and into the future. The key issues to be addressed by activities of the International Union of Forest Research Organization's (IUFRO) Task Force on Endangered Species and Nature Conservation include such issues as: (i) preventing species from being listed by maintaining species populations at sufficient levels that they do not require listing; (ii) recovering threatened and endangered species; (iii) developing management practices and strategies; (iv) balancing actions affecting suites of threatened or endangered species; (v) developing conservation strategies for species without definitive taxonomic treatments; (vi) dealing with global change; (vii) dealing with invasive species; and (viii) restoring critical habitats. © 2008 ISZS, Blackwell Publishing and IOZ/CAS.

  4. Data management issues in mobile ad hoc networks

    PubMed Central

    HARA, Takahiro

    2017-01-01

    Research on mobile ad hoc networks (MANETs) has become a hot research topic since the middle 1990’s. Over the first decade, most research focused on networking techniques, ignoring data management issues. We, however, realized early the importance of data management in MANETs, and have been conducting studies in this area for 15 years. In this review, we summarize some key technical issues related to data management in MANETs, and the studies we have done in addressing these issues, which include placement of data replicas, update management, and query processing with security management. The techniques proposed in our studies have been designed with deep considerations of MANET features including network partitioning, node participation/disappearance, limited network bandwidth, and energy efficiency. Our studies published in early 2000’s have developed a new research field as data management in MANETs. Also, our recent studies are expected to be significant guidelines of new research directions. We conclude the review by discussing some future directions for research. PMID:28496052

  5. Data management issues in mobile ad hoc networks.

    PubMed

    Hara, Takahiro

    2017-01-01

    Research on mobile ad hoc networks (MANETs) has become a hot research topic since the middle 1990's. Over the first decade, most research focused on networking techniques, ignoring data management issues. We, however, realized early the importance of data management in MANETs, and have been conducting studies in this area for 15 years. In this review, we summarize some key technical issues related to data management in MANETs, and the studies we have done in addressing these issues, which include placement of data replicas, update management, and query processing with security management. The techniques proposed in our studies have been designed with deep considerations of MANET features including network partitioning, node participation/disappearance, limited network bandwidth, and energy efficiency. Our studies published in early 2000's have developed a new research field as data management in MANETs. Also, our recent studies are expected to be significant guidelines of new research directions. We conclude the review by discussing some future directions for research.

  6. Issues and Challenges in Higher Education Leadership: Engaging for Change

    ERIC Educational Resources Information Center

    Drew, Glenys

    2010-01-01

    It is proposed from this study that engaging productively with others to achieve change has never been more critical in educational environments, such as universities. Via semi-structured interviews with a cohort of senior leaders from one Australian university, this paper explores their perceptions of the key issues and challenges facing them in…

  7. Future of the Korea national parks: a preliminary Delphi study of key experts

    Treesearch

    Byung-kyu Lee; Wilbur F. LaPage

    2002-01-01

    A preliminary Delphi survey of a panel of key experts who are very knowledgeable of Korean national parks was conducted between February and March in 2001. Park professionals, environmental NGO directors, interested citizens, and retirees identified issues facing the Korean park system (Wave1). Findings from wave I of the survey provided the baseline for a series of...

  8. Stakeholders' views on ethical issues in the practice of in-vitro fertilisation and embryo transfer in Nigeria.

    PubMed

    Ajayi, R A; Dibosa-Osadolor, O J

    2011-09-01

    The provision of IVF for the specialized treatment of infertility has grown very rapidly in Nigeria in recent times, especially within the private sector. The objective of this study was to document the views of key stakeholders regarding salient ethical issues relating to the practice of in-vitro fertilisation (IVF) in Nigeria. A think-tank session was convened with participants drawn from different backgrounds and disciplines to deliberate on ethical issues in IVF. Ten key issues were discussed at this inaugural session. It was unanimously agreed that there are no right or wrong answers when considering the ethics and morality of IVF as these are principally dependent on choice and circumstances. However within the legal and socio-cultural dictates of the Nigerian society, right and wrong may be clearly determined on some issues. With the expansion of the IVF industry and technology in Nigeria, the need to address related ethical issues have become paramount. The forum recommended that it is important that regulatory guidelines are put in place to regulate the practice of IVF in Nigeria and to protect patients' rights and safety.

  9. USSR Space Life Sciences Digest. Index to issues 1-4

    NASA Technical Reports Server (NTRS)

    Teeter, R.; Hooke, L. R.

    1986-01-01

    This document is an index to issues 1 to 4 of the USSR Space Life Sciences Digest and is arranged in three sections. In section 1, abstracts from the first four issues are grouped according to subject; please note the four letter codes in the upper right hand corner of the pages. Section 2 lists the categories according to which digest entries are grouped and cites additional entries relevant to that category by four letter code and entry number in section 1. Refer to section 1 for titles and other pertinent information. Key words are indexed in section 3.

  10. Elementary Science Teacher Education: International Perspectives on Contemporary Issues and Practice

    ERIC Educational Resources Information Center

    Appleton, Ken, Ed.

    2006-01-01

    Reflecting recent policy and standards initiatives, emerging research agendas, and key innovations, this volume provides a contemporary overview of important developments and issues that have that have in recent years shaped elementary science education pre-service courses and professional development, and practices that are shaping future…

  11. Pride or Prejudice--Issues in the History of Children's Nurse Education.

    ERIC Educational Resources Information Center

    Bradley, Susan F.

    2003-01-01

    Training for nurses working with children predates training for care of adults. Key issues in children's nursing have not changed in the last century. They include its undervalued status within the profession and the place of specialized education. (Contains 28 references and commentary by Tony Long.) (SK)

  12. Issues or Identity? Cognitive Foundations of Voter Choice

    PubMed Central

    Jenke, Libby; Huettel, Scott A.

    2016-01-01

    Voter choice is one of the most important problems in political science. The most common models assume that voting is a rational choice based on policy positions (e.g., key issues) and non-policy information (e.g., social identity, personality). Though such models explain macroscopic features of elections, they also reveal important anomalies that have been resistant to explanation. We argue for a new approach that builds upon recent research in cognitive science and neuroscience; specifically, we contend that policy positions and social identities do not combine in merely an additive manner, but compete to determine voter preferences. This model not only explains several key anomalies in voter choice, but also suggests new directions for research in both political science and cognitive science. PMID:27769726

  13. Major Issues Facing the Conservation Movement in the Coming Decade and Beyond.

    ERIC Educational Resources Information Center

    Strong, Maurice

    1984-01-01

    The key issues facing the conservation movement may be grouped into three areas: (1) threats to human health; (2) threats to food and fuel supplies; and (3) long-term threats to the biosphere. Each of these areas is discussed. (JN)

  14. Information superhighway: Issues affecting development

    NASA Astrophysics Data System (ADS)

    1994-09-01

    Technological advances in the transmission of voice, video, and data are fostering fundamental changes in the telecommunications industry. For example, large local telephone companies plan to offer video services in competition with cable and broadcast television, while cable television companies plan to offer local telephone service over their wires in competition with the local telephone companies. The administration believes that these technological changes provide the opportunity to develop an 'Information Superhighway' that could provide every element of society with ready access to data, voice, and video communications. Concurrently, the Congress is considering sweeping changes to telecommunications regulations to keep pace with this dynamic industry. GAO prepared this report to serve as an overview of three key issues that decisionmakers may face as they deliberate telecommunications legislation; it focuses on three pivotal issues they face in formulating new telecommunications legislation: (1) managing the transition to a more competitive local telecommunications marketplace; (2) ensuring that all consumers have access to affordable telecommunications as competition develops; and (3) ensuring that the Information Superhighway provides adequate security, privacy, reliability, and interoperability.

  15. Software Tool Issues

    NASA Astrophysics Data System (ADS)

    Hennell, Michael

    This chapter relies on experience with tool development gained over the last thirty years. It shows that there are a large number of techniques that contribute to any successful project, and that formality is always the key: a modern software test tool is based on a firm mathematical foundation. After a brief introduction, Section 2 recalls and extends the terminology of Chapter 1. Section 3 discusses the the design of different sorts of static and dynamic analysis tools. Nine important issues to be taken into consideration when evaluating such tools are presented in Section 4. Section 5 investigates the interplay between testing and proof. In Section 6, we call for developers to take their own medicine and verify their tools. Finally, we conclude in Section 7 with a summary of our main messages, emphasising the important role of testing.

  16. Coupled Biological-Geomechanical-Geochemical Effects of the Disturbed Rock Zone on the Performance of the Waste Isolation Pilot Plant

    NASA Astrophysics Data System (ADS)

    Dunagan, S. C.; Herrick, C. G.; Lee, M. Y.

    2008-12-01

    The Waste Isolation Pilot Plant (WIPP) is located at a depth of 655 m in bedded salt in southeastern New Mexico and is operated by the U.S. Department of Energy as a deep underground disposal facility for transuranic (TRU) waste. The WIPP must comply with the EPA's environmental regulations that require a probabilistic risk analysis of releases of radionuclides due to inadvertent human intrusion into the repository at some time during the 10,000-year regulatory period. Sandia National Laboratories conducts performance assessments (PAs) of the WIPP using a system of computer codes representing the evolution of underground repository and emplaced TRU waste in order to demonstrate compliance. One of the important features modeled in a PA is the disturbed rock zone (DRZ) surrounding the emplacement rooms in the repository. The extent and permeability of DRZ play a significant role in the potential radionuclide release scenarios. We evaluated the phenomena occurring in the repository that affect the DRZ and their potential effects on the extent and permeability of the DRZ. Furthermore, we examined the DRZ's role in determining the performance of the repository. Pressure in the completely sealed repository will be increased by creep closure of the salt and degradation of TRU waste contents by microbial activity in the repository. An increased pressure in the repository will reduce the extent and permeability of the DRZ. The reduced DRZ extent and permeability will decrease the amount of brine that is available to interact with the waste. Furthermore, the potential for radionuclide release from the repository is dependent on the amount of brine that enters the repository. As a result of these coupled biological-geomechanical-geochemical phenomena, the extent and permeability of the DRZ has a significant impact on the potential radionuclide releases from the repository and, in turn, the repository performance. Sandia is a multi program laboratory operated by Sandia

  17. Security and skills: the two key issues in health worker migration

    PubMed Central

    Bidwell, Posy; Laxmikanth, Pallavi; Blacklock, Claire; Hayward, Gail; Willcox, Merlin; Peersman, Wim; Moosa, Shabir; Mant, David

    2014-01-01

    Background Migration of health workers from Africa continues to undermine the universal provision of quality health care. South Africa is an epicentre for migration – it exports more health workers to high-income countries than any other African country and imports health workers from its lower-income neighbours to fill the gap. Although an inter-governmental agreement in 2003 reduced the very high numbers migrating from South Africa to the United Kingdom, migration continues to other high-income English-speaking countries and few workers seem to return although the financial incentive to work abroad has lessened. A deeper understanding of reasons for migration from South Africa and post-migration experiences is therefore needed to underpin policy which is developed in order to improve retention within source countries and encourage return. Methods Semi-structured interviews were conducted with 16 South African doctors and nurses who had migrated to the United Kingdom. Interviews explored factors influencing the decision to migrate and post-migration experiences. Results Salary, career progression, and poor working conditions were not major push factors for migration. Many health workers reported that they had previously overcome these issues within the South African healthcare system by migrating to the private sector. Overwhelmingly, the major push factors were insecurity, high levels of crime, and racial tension. Although the wish to work and train in what was perceived to be a first-class care system was a pull factor to migrate to the United Kingdom, many were disappointed by the experience. Instead of obtaining new skills, many (particularly nurses) felt they had become ‘de-skilled’. Many also felt that working conditions and opportunities for them in the UK National Health Service (NHS) compared unfavourably with the private sector in South Africa. Conclusions Migration from South Africa seems unlikely to diminish until the major concerns over security

  18. Security and skills: the two key issues in health worker migration.

    PubMed

    Bidwell, Posy; Laxmikanth, Pallavi; Blacklock, Claire; Hayward, Gail; Willcox, Merlin; Peersman, Wim; Moosa, Shabir; Mant, David

    2014-01-01

    Migration of health workers from Africa continues to undermine the universal provision of quality health care. South Africa is an epicentre for migration--it exports more health workers to high-income countries than any other African country and imports health workers from its lower-income neighbours to fill the gap. Although an inter-governmental agreement in 2003 reduced the very high numbers migrating from South Africa to the United Kingdom, migration continues to other high-income English-speaking countries and few workers seem to return although the financial incentive to work abroad has lessened. A deeper understanding of reasons for migration from South Africa and post-migration experiences is therefore needed to underpin policy which is developed in order to improve retention within source countries and encourage return. Semi-structured interviews were conducted with 16 South African doctors and nurses who had migrated to the United Kingdom. Interviews explored factors influencing the decision to migrate and post-migration experiences. Salary, career progression, and poor working conditions were not major push factors for migration. Many health workers reported that they had previously overcome these issues within the South African healthcare system by migrating to the private sector. Overwhelmingly, the major push factors were insecurity, high levels of crime, and racial tension. Although the wish to work and train in what was perceived to be a first-class care system was a pull factor to migrate to the United Kingdom, many were disappointed by the experience. Instead of obtaining new skills, many (particularly nurses) felt they had become 'de-skilled'. Many also felt that working conditions and opportunities for them in the UK National Health Service (NHS) compared unfavourably with the private sector in South Africa. Migration from South Africa seems unlikely to diminish until the major concerns over security, crime, and racial tensions are resolved

  19. Assessment of interpersonal aggression and violence: introduction to the special issue.

    PubMed

    Edens, John F; Douglas, Kevin S

    2006-09-01

    Violence and interpersonal aggression are considered major public health problems throughout the world. Yet there is considerable variability in how these terms are operationalized, measured, and studied in the social sciences, which can lead to ambiguity and confusion in the field. In this introduction to the special issue, the authors highlight some of the difficulties inherent in studying interpersonal aggression and violence and briefly review the heterogeneous nature of the research conducted in this area. The authors conclude with a summary of the key findings of the articles that appear in this special issue.

  20. Diabetes and end of life: ethical and methodological issues in gathering evidence to guide care.

    PubMed

    Dunning, Trisha; Duggan, Nicole; Savage, Sally; Martin, Peter

    2013-03-01

    Providing palliative care for people with diabetes at the end of life is part of the chronic disease care trajectory, but end of life care is complex and the presence of diabetes further complicates management. The aim of the paper is to discuss the ethical and methodological issues encountered when undertaking research to develop guidelines for managing diabetes at the end of life and the strategies used to address the issues. The issues emerged as we developed guidelines for managing diabetes at the end of life, which included conducting individual interviews with 14 people with diabetes requiring palliative care and 10 family members. A reflexive researcher journal was maintained throughout the guideline development process. The interview transcripts and researcher's journal were analysed to determine key methodological, ethical and researcher-related issues. Key themes were vulnerability of the sampling population, methodological issues included recruiting participants and ensuring rigor, ethical issues concerned benefit and risk, justice, autonomy, privacy, professional boundaries and informed consent. Researcher-related issues were identified such as managing participant distress and their own emotional distress. People were willing to discuss end of life diabetes management preferences. Undertaking research with people at the end of life is complex because of their vulnerability and the ethical issues involved. However, the ethical principles of autonomy and justice apply and people should be given the relevant information and opportunity to decide whether to participate or not. © 2012 The Authors. Scandinavian Journal of Caring Sciences © 2012 Nordic College of Caring Science.